afr: allow I/O when favorite-child-policy is enabled

Problem: Currently, I/O on a split-brained file fails even when the favorite-child-policy is set until the self-heal is complete. Fix: If a valid 'source' is found using the set favorite-child-policy, inspect and reset the afr pending xattrs on the 'sinks' (inside appropriate locks), refresh the inode and then proceed with the read or write transaction. The resetting itself happens in the self-heal code and hence can also happen in the client side background-heal or by the shd's index-heal in addition to the txn code path explained above. When it happens in via heal, we also add checks in undo-pending to not reset the sink xattrs again. Change-Id: Ic8c1317720cb26bd114b6fe6af4e58c73b864626 BUG: 1386188 Signed-off-by: Ravishankar N <ravishankar@redhat.com> Reported-by: Simon Turcotte-Langevin <simon.turcotte-langevin@ubisoft.com> Reviewed-on: http://review.gluster.org/15673 Tested-by: Pranith Kumar Karampuri <pkarampu@redhat.com> Smoke: Gluster Build System <jenkins@build.gluster.org> Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
author: Ravishankar N <ravishankar@redhat.com> 2016-11-26 21:24:01 +0530
committer: Pranith Kumar Karampuri <pkarampu@redhat.com> 2016-11-27 23:51:59 -0800
commit: a07ddd8fcc8dcdcf7ccfa61211d258f13b9f9229 (patch)
tree: 8192cfc5b2553043dc9511b386bf8894c7972746 /tests/basic/afr
parent: 2214501d6045b45dde469c5a476c86b6cf464c34 (diff)
0 files changed, 0 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore
index e9d41a20b..ff253c1da 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,26 +8,41 @@ install-sh
 ltmain.sh
 Makefile.in
 missing
+py-compile
 *.sw?
 *~
 *.lo
 *.la
 *.o
+*.tar.gz
+*.rpm
 .libs
+.deps
 Makefile
 stamp-h1
 
 # Generated files
-extras/init.d/glusterfs-server.plist
-extras/init.d/glusterfsd-Debian
-extras/init.d/glusterfsd-Redhat
-extras/init.d/glusterfsd-SuSE
-glusterfs.spec
-libtool
-xlators/mount/fuse/utils/mount.glusterfs
-xlators/mount/fuse/utils/mount_glusterfs
+api/examples/__init__.py*
+api/examples/setup.py
 argp-standalone/libargp.a
+contrib/uuid/uuid_types.h
+extras/init.d/glusterd-Debian
+extras/init.d/glusterd-Redhat
+extras/init.d/glusterd-SuSE
+extras/init.d/glusterd.plist
+extras/ocf/glusterd
+extras/ocf/volume
+extras/who-wrote-glusterfs/gitdm
+glusterfs-api.pc
+glusterfs.spec
 glusterfsd/src/glusterfsd
+libgfchangelog.pc
 libglusterfs/src/spec.lex.c
 libglusterfs/src/y.tab.c
 libglusterfs/src/y.tab.h
+libtool
+run-tests.sh
+ufo/.tox
+ufo/test/unit/.coverage
+xlators/mount/fuse/utils/mount.glusterfs
+xlators/mount/fuse/utils/mount_glusterfs
diff --git a/.mailmap b/.mailmap
new file mode 100644
index 000000000..6bcd95dea
--- /dev/null
+++ b/.mailmap
@@ -0,0 +1,31 @@
+# .mailmap, see 'git short-log --help' for details
+#
+# Listing of contributors that filed patches with different email addresses.
+# Format: <name> <main-email> <alias> [<alias> ...]
+#
+
+Amar Tumballi <amarts@redhat.com> <amar@gluster.com> <amar@del.gluster.com>
+Anand Avati <avati@redhat.com> <avati@gluster.com> <avati@dev.gluster.com> <avati@amp.gluster.com> <avati@blackhole.gluster.com>
+Anush Shetty <ashetty@redhat.com> <anush@gluster.com>
+Csaba Henk <csaba@redhat.com> <csaba@gluster.com> <csaba@lowlife.hu> <csaba@zresearch.com>
+Harshavardhana <fharshav@redhat.com> <harsha@gluster.com> <harsha@zresearch.com> <harsha@dev.gluster.com> <harsha@harshavardhana.net>
+Kaleb S. KEITHLEY <kkeithle@redhat.com> <kkeithle@f16node1.kkeithle.usersys.redhat.com>
+Kaushal M <kaushal@redhat.com> <kaushal@gluster.com>
+Kaushik BV <kbudiger@redhat.com> <kaushikbv@gluster.com>
+Krishna Srinivas <ksriniva@redhat.com> <krishna@gluster.com> <krishna@zresearch.com> <krishna@guest-laptop>
+Krishnan Parthasarathi <kparthas@redhat.com> <kp@gluster.com>
+Louis Zuckerman <louiszuckerman@gmail.com> <me@louiszuckerman.com>
+M S Vishwanath Bhat <vbhat@redhat.com> <msvbhat@gmail.com> <vishwanath@gluster.com>
+Pavan Sondur <pavan@gluster.com> <pavan@dev.gluster.com>
+Pete Zaitcev <zaitcev@kotori.zaitcev.us> <zaitcev@yahoo.com>
+Pranith Kumar K <pkarampu@redhat.com> <pranithk@gluster.com>
+Raghavendra Bhat <raghavendra@redhat.com> <raghavendrabhat@gluster.com>
+Raghavendra G <rgowdapp@redhat.com> <raghavendra@gluster.com> <raghavendra@zresearch.com>
+Rahul C S <rahulcs@redhat.com> <rahulcssjce@gmail.com>
+Rajesh Amaravathi <rajesh@redhat.com> <rajesh@gluster.com> <rajesh.amaravathi@gmail.com>
+Shehjar Tikoo <shehjart@gluster.com> <shehjart@zresearch.com>
+Venky Shankar <vshankar@redhat.com> <venky@gluster.com>
+Vijay Bellur <vbellur@redhat.com> <vijay@gluster.com> <vijay@dev.gluster.com>
+Vijaykumar Koppad <vkoppad@redhat.com> <vijaykumar.koppad@gmail.com>
+Vikas Gorur <vikas@gluster.com> <vikas@zresearch.com>
+shishir gowda <sgowda@redhat.com> <shishirng@gluster.com>
diff --git a/.unittests b/.unittests
deleted file mode 100755
index ad2a3a34a..000000000
--- a/.unittests
+++ /dev/null
@@ -1,5 +0,0 @@
-#!/bin/bash
-
-cd ufo
-./.unittests $@
-cd -
diff --git a/Makefile.am b/Makefile.am
index 5f3cf322d..598ebb410 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,13 +1,16 @@
 EXTRA_DIST = autogen.sh \
 	COPYING-GPLV2 COPYING-LGPLV3 \
 	INSTALL README AUTHORS THANKS NEWS \
-	glusterfs.spec glusterfs-api.pc.in
+	glusterfs.spec glusterfs-api.pc.in libgfchangelog.pc.in \
+	error-codes.json gf-error-codes.h.template \
+	gen-headers.py run-tests.sh \
+	$(shell find $(top_srcdir)/tests -type f -print)
 
 SUBDIRS = argp-standalone libglusterfs rpc api xlators glusterfsd \
-	$(FUSERMOUNT_SUBDIR) doc extras cli
+	$(FUSERMOUNT_SUBDIR) doc extras cli @SYNCDAEMON_SUBDIR@
 
 pkgconfigdir = @pkgconfigdir@
-pkgconfig_DATA = glusterfs-api.pc
+pkgconfig_DATA = glusterfs-api.pc libgfchangelog.pc
 
 CLEANFILES =
 
@@ -18,8 +21,9 @@ gitclean: distclean
 	rm -fr autom4te.cache
 	rm -f missing aclocal.m4 config.h.in config.guess config.sub ltmain.sh install-sh configure depcomp
 	rm -fr argp-standalone/autom4te.cache
-	rm -f argp-standalone/aclocal.m4 argp-standalone/config.h.in argp-standalone/configure argp-standalone/depcomp argp-standalone/install-sh argp-standalone/missing
+	rm -f argp-standalone/aclocal.m4 argp-standalone/config.h.in
+	rm -f argp-standalone/configure argp-standalone/depcomp
+	rm -f argp-standalone/install-sh argp-standalone/missing
 
 dist-hook:
-	sh -c "cd $(srcdir) && git diff && echo ===== git log ==== && git log" \
-	> $(distdir)/ChangeLog
+	(cd $(srcdir) && git diff && echo ===== git log ==== && git log) > $(distdir)/ChangeLog
diff --git a/api/Makefile.am b/api/Makefile.am
index af437a64d..f0ad1ee97 100644
--- a/api/Makefile.am
+++ b/api/Makefile.am
@@ -1 +1 @@
-SUBDIRS = src
+SUBDIRS = src examples
diff --git a/api/examples/Makefile.am b/api/examples/Makefile.am
index 6048bb1c8..05f40ff53 100644
--- a/api/examples/Makefile.am
+++ b/api/examples/Makefile.am
@@ -1,4 +1,6 @@
-noinst_PROGRAMS = glfsxmp
+EXTRA_PROGRAMS = glfsxmp
 glfsxmp_SOURCES = glfsxmp.c
 glfsxmp_CFLAGS = $(GLFS_CFLAGS) -Wall
-glfsxmp_LDADD = $(GLFS_LIBS)
-\ No newline at end of file
+glfsxmp_LDADD = $(GLFS_LIBS) -lrt
+
+EXTRA_DIST = gfapi.py
diff --git a/api/examples/README b/api/examples/README
index 8f0bab697..4d2b521f7 100644
--- a/api/examples/README
+++ b/api/examples/README
@@ -17,3 +17,20 @@ install glusterfs-api RPM.
 Make sure your LDFLAGS includes -L/path/to/lib where libgfapi.so is
 installed and -I/path/to/include/glusterfs where the 'api' directory
 containing the headers are available.
+
+glfsxmp.c
+=========
+
+glfsxmp.c is an example application which uses libgfapi
+
+Compilation Steps For glfsxmp.c
+===============================
+
+1. $./autogen.sh
+2. $./configure
+
+Note: Before running ./configure , as mentioned above, you need to
+      take care of #1 or #2 i.e. pkg-config path or LDFLAGS and
+      -I/<path> with correct values.
+
+3. $make glfsxmp
diff --git a/api/examples/gfapi.py b/api/examples/gfapi.py
index 8fc3bfa4c..3ac67f4d5 100644..100755
--- a/api/examples/gfapi.py
+++ b/api/examples/gfapi.py
@@ -1,29 +1,422 @@
-import ctypes
+#!/usr/bin/python
+
+from ctypes import *
+from ctypes.util import find_library
 import os
 import sys
+import time
+import types
 
 # Looks like ctypes is having trouble with dependencies, so just force them to
 # load with RTLD_GLOBAL until I figure that out.
-glfs = ctypes.CDLL("libglusterfs.so",ctypes.RTLD_GLOBAL)
-xdr = ctypes.CDLL("libgfxdr.so",ctypes.RTLD_GLOBAL)
-api = ctypes.CDLL("api/libgfapi.so",ctypes.RTLD_GLOBAL)
-
-fs = api.glfs_new(sys.argv[1])
-api.glfs_set_logging(fs,"/dev/stderr",7)
-api.glfs_set_volfile_server(fs,"tcp","localhost",24007)
-api.glfs_init(fs)
-print "Initialized volume"
-
-fd = api.glfs_creat(fs,sys.argv[2],os.O_RDWR,0644)
-print "Created file"
-
-# Read anything that's there from before.
-rbuf = ctypes.create_string_buffer(32)
-if api.glfs_read(fd,rbuf,32,0) > 0:
-	print "old data = %s" % rbuf.value
-
-# Write some new data.
-api.glfs_lseek(fd,0,os.SEEK_SET)
-wrote = api.glfs_write(fd,sys.argv[3],len(sys.argv[3]),0)
-if wrote > 0:
-	print "wrote %d bytes" % wrote
+glfs = CDLL(find_library("glusterfs"),RTLD_GLOBAL)
+xdr = CDLL(find_library("gfxdr"),RTLD_GLOBAL)
+api = CDLL(find_library("gfapi"),RTLD_GLOBAL)
+
+# Wow, the Linux kernel folks really play nasty games with this structure.  If
+# you look at the man page for stat(2) and then at this definition you'll note
+# two discrepancies.  First, we seem to have st_nlink and st_mode reversed.  In
+# fact that's exactly how they're defined *for 64-bit systems*; for 32-bit
+# they're in the man-page order.  Even uglier, the man page makes no mention of
+# the *nsec fields, but they are very much present and if they're not included
+# then we get memory corruption because libgfapi has a structure definition
+# that's longer than ours and they overwrite some random bit of memory after
+# the space we allocated.  Yes, that's all very disgusting, and I'm still not
+# sure this will really work on 32-bit because all of the field types are so
+# obfuscated behind macros and feature checks.
+class Stat (Structure):
+        _fields_ = [
+                ("st_dev",              c_ulong),
+                ("st_ino",              c_ulong),
+                ("st_nlink",            c_ulong),
+                ("st_mode",             c_uint),
+                ("st_uid",              c_uint),
+                ("st_gid",              c_uint),
+                ("st_rdev",             c_ulong),
+                ("st_size",             c_ulong),
+                ("st_blksize",          c_ulong),
+                ("st_blocks",           c_ulong),
+                ("st_atime",            c_ulong),
+                ("st_atimensec",        c_ulong),
+                ("st_mtime",            c_ulong),
+                ("st_mtimensec",        c_ulong),
+                ("st_ctime",            c_ulong),
+                ("st_ctimensec",        c_ulong),
+        ]
+api.glfs_creat.restype = c_void_p
+api.glfs_open.restype = c_void_p
+api.glfs_lstat.restype = c_int
+api.glfs_lstat.argtypes = [c_void_p, c_char_p, POINTER(Stat)]
+
+class Dirent (Structure):
+        _fields_ = [
+                ("d_ino",       c_ulong),
+                ("d_off",       c_ulong),
+                ("d_reclen",    c_ushort),
+                ("d_type",      c_char),
+                ("d_name",      c_char * 256),
+        ]
+api.glfs_opendir.restype = c_void_p
+api.glfs_readdir_r.restype = c_int
+api.glfs_readdir_r.argtypes = [c_void_p, POINTER(Dirent),
+                               POINTER(POINTER(Dirent))]
+
+# There's a bit of ctypes glitchiness around __del__ functions and module-level
+# variables.  If we unload the module while we still have references to File or
+# Volume objects, the module-level variables might have disappeared by the time
+# __del__ gets called.  Therefore the objects hold references which they
+# release when __del__ is done.  We only actually use the object-local values
+# in __del__; for clarity, we just use the simpler module-level form elsewhere.
+
+class File(object):
+
+        def __init__ (self, fd):
+                # Add a reference so the module-level variable "api" doesn't
+                # get yanked out from under us (see comment above File def'n).
+                self._api = api
+                self.fd = fd
+
+        def __del__ (self):
+                self._api.glfs_close(self.fd)
+                self._api = None
+
+        # File operations, in alphabetical order.
+
+        def fsync (self):
+                return api.glfs_fsync(self.fd)
+
+        def read (self, buflen, flags=0):
+                rbuf = create_string_buffer(buflen)
+                rc = api.glfs_read(self.fd,rbuf,buflen,flags)
+                if rc > 0:
+                        return rbuf.value[:rc]
+                else:
+                        return rc
+
+        def read_buffer (self, buf, flags=0):
+                return api.glfs_read(self.fd,buf,len(buf),flags)
+
+        def write (self, data, flags=0):
+                return api.glfs_write(self.fd,data,len(data),flags)
+
+        def fallocate (self, mode, offset, len):
+            return api.glfs_fallocate(self.fd, mode, offset, len)
+
+        def discard (self, offset, len):
+            return api.glfs_discard(self.fd, offset, len)
+
+
+class Dir(object):
+
+        def __init__ (self, fd):
+                # Add a reference so the module-level variable "api" doesn't
+                # get yanked out from under us (see comment above File def'n).
+                self._api = api
+                self.fd = fd
+                self.cursor = POINTER(Dirent)()
+
+        def __del__ (self):
+                self._api.glfs_closedir(self.fd)
+                self._api = None
+
+        def next (self):
+                entry = Dirent()
+                entry.d_reclen = 256
+                rc = api.glfs_readdir_r(self.fd,byref(entry),byref(self.cursor))
+                if (rc < 0) or (not self.cursor) or (not self.cursor.contents):
+                        return rc
+                return entry
+
+class Volume(object):
+
+        # Housekeeping functions.
+
+        def __init__ (self, host, volid, proto="tcp", port=24007):
+                # Add a reference so the module-level variable "api" doesn't
+                # get yanked out from under us (see comment above File def'n).
+                self._api = api
+                self.fs = api.glfs_new(volid)
+                api.glfs_set_volfile_server(self.fs,proto,host,port)
+
+        def __del__ (self):
+                self._api.glfs_fini(self.fs)
+                self._api = None
+
+        def set_logging (self, path, level):
+                api.glfs_set_logging(self.fs,path,level)
+
+        def mount (self):
+                api.glfs_init(self.fs)
+
+        # File operations, in alphabetical order.
+
+        def creat (self, path, flags, mode):
+                fd = api.glfs_creat(self.fs,path,flags,mode)
+                if not fd:
+                        return fd
+                return File(fd)
+
+        def getxattr (self, path, key, maxlen):
+                buf = create_string_buffer(maxlen)
+                rc = api.glfs_getxattr(self.fs,path,key,buf,maxlen)
+                if rc < 0:
+                        return rc
+                return buf.value[:rc]
+
+        def listxattr (self, path):
+                buf = create_string_buffer(512)
+                rc = api.glfs_listxattr(self.fs,path,buf,512)
+                if rc < 0:
+                        return rc
+                xattrs = []
+                # Parsing character by character is ugly, but it seems like the
+                # easiest way to deal with the "strings separated by NUL in one
+                # buffer" format.
+                i = 0
+                while i < rc:
+                        new_xa = buf.raw[i]
+                        i += 1
+                        while i < rc:
+                                next_char = buf.raw[i]
+                                i += 1
+                                if next_char == '\0':
+                                        xattrs.append(new_xa)
+                                        break
+                                new_xa += next_char
+                xattrs.sort()
+                return xattrs
+
+        def lstat (self, path):
+                x = Stat()
+                rc = api.glfs_lstat(self.fs,path,byref(x))
+                if rc >= 0:
+                        return x
+                else:
+                        return rc
+
+        def mkdir (self, path):
+                return api.glfs_mkdir(self.fs,path)
+
+        def open (self, path, flags):
+                fd = api.glfs_open(self.fs,path,flags)
+                if not fd:
+                        return fd
+                return File(fd)
+
+        def opendir (self, path):
+                fd = api.glfs_opendir(self.fs,path)
+                if not fd:
+                        return fd
+                return Dir(fd)
+
+        def rename (self, opath, npath):
+                return api.glfs_rename(self.fs,opath,npath)
+
+        def rmdir (self, path):
+                return api.glfs_rmdir(self.fs,path)
+
+        def setxattr (self, path, key, value, vlen):
+                return api.glfs_setxattr(self.fs,path,key,value,vlen,0)
+
+        def unlink (self, path):
+                return api.glfs_unlink(self.fs,path)
+
+if __name__ == "__main__":
+        def test_create_write (vol, path, data):
+                mypath = path + ".io"
+                fd = vol.creat(mypath,os.O_WRONLY|os.O_EXCL,0644)
+                if not fd:
+                        return False, "creat error"
+                rc = fd.write(data)
+                if rc != len(data):
+                        return False, "wrote %d/%d bytes" % (rc, len(data))
+                return True, "wrote %d bytes" % rc
+
+        # TBD: this test fails if we do create, open, write, read
+        def test_open_read (vol, path, data):
+                mypath = path + ".io"
+                fd = vol.open(mypath,os.O_RDONLY)
+                if not fd:
+                        return False, "open error"
+                dlen = len(data) * 2
+                buf = fd.read(dlen)
+                if type(buf) == types.IntType:
+                        return False, "read error %d" % buf
+                if len(buf) != len(data):
+                        return False, "read %d/%d bytes" % (len(buf), len(data))
+                return True, "read '%s'" % buf
+
+        def test_lstat (vol, path, data):
+                mypath = path + ".io"
+                sb = vol.lstat(mypath)
+                if type(sb) == types.IntType:
+                        return False, "lstat error %d" % sb
+                if sb.st_size != len(data):
+                        return False, "lstat size is %d, expected %d" % (
+                                sb.st_size, len(data))
+                return True, "lstat got correct size %d" % sb.st_size
+
+        def test_rename (vol, path, data):
+                opath = path + ".io"
+                npath = path + ".tmp"
+                rc = vol.rename(opath,npath)
+                if rc < 0:
+                        return False, "rename error %d" % rc
+                ofd = vol.open(opath,os.O_RDWR)
+                if isinstance(ofd,File):
+                        return False, "old path working after rename"
+                nfd = vol.open(npath,os.O_RDWR)
+                if isinstance(nfd,File):
+                        return False, "new path not working after rename"
+                return True, "rename worked"
+
+        def test_unlink (vol, path, data):
+                mypath = path + ".tmp"
+                rc = vol.unlink(mypath)
+                if rc < 0:
+                        return False, "unlink error %d" % fd
+                fd = vol.open(mypath,os.O_RDWR)
+                if isinstance(fd,File):
+                        return False, "path still usable after unlink"
+                return True, "unlink worked"
+
+        def test_mkdir (vol, path, data):
+                mypath = path + ".dir"
+                rc = vol.mkdir(mypath)
+                if rc < 0:
+                        return False, "mkdir error %d" % rc
+                return True, "mkdir worked"
+
+        def test_create_in_dir (vol, path, data):
+                mypath = path + ".dir/probe"
+                fd = vol.creat(mypath,os.O_RDWR,0644)
+                if not isinstance(fd,File):
+                        return False, "create (in dir) error"
+                return True, "create (in dir) worked"
+
+        def test_dir_listing (vol, path, data):
+                mypath = path + ".dir"
+                fd = vol.opendir(mypath)
+                if not isinstance(fd,Dir):
+                        return False, "opendir error %d" % fd
+                files = []
+                while True:
+                        ent = fd.next()
+                        if not isinstance(ent,Dirent):
+                                break
+                        name = ent.d_name[:ent.d_reclen]
+                        files.append(name)
+                if files != [".", "..", "probe"]:
+                        return False, "wrong directory contents"
+                return True, "directory listing worked"
+
+        def test_unlink_in_dir (vol, path, data):
+                mypath = path + ".dir/probe"
+                rc = vol.unlink(mypath)
+                if rc < 0:
+                        return False, "unlink (in dir) error %d" % rc
+                return True, "unlink (in dir) worked"
+
+        def test_rmdir (vol, path, data):
+                mypath = path + ".dir"
+                rc = vol.rmdir(mypath)
+                if rc < 0:
+                        return False, "rmdir error %d" % rc
+                sb = vol.lstat(mypath)
+                if not isinstance(sb,Stat):
+                        return False, "dir still there after rmdir"
+                return True, "rmdir worked"
+
+        def test_setxattr (vol, path, data):
+                mypath = path + ".xa"
+                fd = vol.creat(mypath,os.O_RDWR|os.O_EXCL,0644)
+                if not fd:
+                        return False, "creat (xattr test) error"
+                key1, key2 = "hello", "goodbye"
+                if vol.setxattr(mypath,"trusted.key1",key1,len(key1)) < 0:
+                        return False, "setxattr (key1) error"
+                if vol.setxattr(mypath,"trusted.key2",key2,len(key2)) < 0:
+                        return False, "setxattr (key2) error"
+                return True, "setxattr worked"
+
+        def test_getxattr (vol, path, data):
+                mypath = path + ".xa"
+                buf = vol.getxattr(mypath,"trusted.key1",32)
+                if type(buf) == types.IntType:
+                        return False, "getxattr error"
+                if buf != "hello":
+                        return False, "wrong getxattr value %s" % buf
+                return True, "getxattr worked"
+
+        def test_listxattr (vol, path, data):
+                mypath = path + ".xa"
+                xattrs = vol.listxattr(mypath)
+                if type(xattrs) == types.IntType:
+                        return False, "listxattr error"
+                if xattrs != ["trusted.key1","trusted.key2"]:
+                        return False, "wrong listxattr value %s" % repr(xattrs)
+                return True, "listxattr worked"
+
+        def test_fallocate (vol, path, data):
+                mypath = path + ".io"
+                fd = vol.creat(mypath,os.O_WRONLY|os.O_EXCL,0644)
+                if not fd:
+                        return False, "creat error"
+		rc = fd.fallocate(0, 0, 1024*1024)
+                if rc != 0:
+                        return False, "fallocate error"
+		rc = fd.discard(4096, 4096)
+		if rc != 0:
+			return False, "discard error"
+                return True, "fallocate/discard worked"
+
+        test_list = (
+                test_create_write,
+                test_open_read,
+                test_lstat,
+                test_rename,
+                test_unlink,
+                test_mkdir,
+                test_create_in_dir,
+                test_dir_listing,
+                test_unlink_in_dir,
+                test_rmdir,
+                test_setxattr,
+                test_getxattr,
+                test_listxattr,
+                test_fallocate,
+        )
+
+        ok_to_fail = (
+                # TBD: this fails opening the new file, even though the file
+                # did get renamed.  Looks like a gfapi bug, not ours.
+                (test_rename, "new path not working after rename"),
+                # TBD: similar, call returns error even though it worked
+                (test_rmdir, "dir still there after rmdir"),
+        )
+
+        volid, path = sys.argv[1:3]
+        data = "fubar"
+        vol = Volume("localhost",volid)
+        vol.set_logging("/dev/null",7)
+        #vol.set_logging("/dev/stderr",7)
+        vol.mount()
+
+        failures = 0
+        expected = 0
+        for t in test_list:
+                rc, msg = t(vol,path,data)
+                if rc:
+                        print "PASS: %s" % msg
+                else:
+                        print "FAIL: %s" % msg
+                        failures += 1
+                        for otf in ok_to_fail:
+                                if (t == otf[0]) and (msg == otf[1]):
+                                        print "  (skipping known failure)"
+                                        expected += 1
+                                        break # from the *inner* for loop
+                        else:
+                                break # from the *outer* for loop
+
+        print "%d failures (%d expected)" % (failures, expected)
diff --git a/api/examples/glfsxmp.c b/api/examples/glfsxmp.c
index b359cc744..600d72fb5 100644
--- a/api/examples/glfsxmp.c
+++ b/api/examples/glfsxmp.c
@@ -1,6 +1,8 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <errno.h>
 #include "api/glfs.h"
+#include "api/glfs-handles.h"
 #include <string.h>
 #include <time.h>
 
@@ -8,163 +10,1589 @@
 int
 test_dirops (glfs_t *fs)
 {
-	glfs_fd_t *fd = NULL;
-	char buf[512];
-	struct dirent *entry = NULL;
+        glfs_fd_t *fd = NULL;
+        char buf[512];
+        struct dirent *entry = NULL;
 
-	fd = glfs_opendir (fs, "/");
-	if (!fd) {
-		fprintf (stderr, "/: %s\n", strerror (errno));
-		return -1;
-	}
+        fd = glfs_opendir (fs, "/");
+        if (!fd) {
+                fprintf (stderr, "/: %s\n", strerror (errno));
+                return -1;
+        }
 
-	fprintf (stderr, "Entries:\n");
-	while (glfs_readdir_r (fd, (struct dirent *)buf, &entry), entry) {
-		fprintf (stderr, "%s: %lu\n", entry->d_name, glfs_telldir (fd));
-	}
+        fprintf (stderr, "Entries:\n");
+        while (glfs_readdir_r (fd, (struct dirent *)buf, &entry), entry) {
+                fprintf (stderr, "%s: %lu\n", entry->d_name, glfs_telldir (fd));
+        }
 
-	glfs_closedir (fd);
-	return 0;
+        glfs_closedir (fd);
+        return 0;
 }
 
 
 int
 test_xattr (glfs_t *fs)
 {
-	char *filename = "/filename2";
-	char buf[512];
-	char *ptr;
-	int ret;
+        char *filename = "/filename2";
+        char buf[512];
+        char *ptr;
+        int ret;
 
-	ret = glfs_setxattr (fs, filename, "user.testkey", "testval", 8, 0);
-	fprintf (stderr, "setxattr(%s): %d (%s)\n", filename, ret,
-		 strerror (errno));
+        ret = glfs_setxattr (fs, filename, "user.testkey", "testval", 8, 0);
+        fprintf (stderr, "setxattr(%s): %d (%s)\n", filename, ret,
+                 strerror (errno));
 
-	ret = glfs_setxattr (fs, filename, "user.testkey2", "testval", 8, 0);
-	fprintf (stderr, "setxattr(%s): %d (%s)\n", filename, ret,
-		 strerror (errno));
+        ret = glfs_setxattr (fs, filename, "user.testkey2", "testval", 8, 0);
+        fprintf (stderr, "setxattr(%s): %d (%s)\n", filename, ret,
+                 strerror (errno));
 
-	ret = glfs_listxattr (fs, filename, buf, 512);
-	fprintf (stderr, "listxattr(%s): %d (%s)\n", filename, ret,
-		 strerror (errno));
-	if (ret < 0)
-		return -1;
+        ret = glfs_listxattr (fs, filename, buf, 512);
+        fprintf (stderr, "listxattr(%s): %d (%s)\n", filename, ret,
+                 strerror (errno));
+        if (ret < 0)
+                return -1;
 
-	for (ptr = buf; ptr < buf + ret; ptr++) {
-		printf ("key=%s\n", ptr);
-		ptr += strlen (ptr);
-	}
+        for (ptr = buf; ptr < buf + ret; ptr++) {
+                printf ("key=%s\n", ptr);
+                ptr += strlen (ptr);
+        }
 
-	return 0;
+        return 0;
 }
 
 
 int
+test_chdir (glfs_t *fs)
+{
+        int ret = -1;
+        char *topdir = "/topdir";
+        char *linkdir = "/linkdir";
+        char *subdir = "./subdir";
+        char *respath = NULL;
+        char pathbuf[4096];
+
+        ret = glfs_mkdir (fs, topdir, 0755);
+        if (ret) {
+                fprintf (stderr, "mkdir(%s): %s\n", topdir, strerror (errno));
+                return -1;
+        }
+
+        respath = glfs_getcwd (fs, pathbuf, 4096);
+        fprintf (stdout, "getcwd() = %s\n", respath);
+
+        ret = glfs_symlink (fs, topdir, linkdir);
+        if (ret) {
+                fprintf (stderr, "symlink(%s, %s): %s\n", topdir, linkdir, strerror (errno));
+                return -1;
+        }
+
+        ret = glfs_chdir (fs, linkdir);
+        if (ret) {
+                fprintf (stderr, "chdir(%s): %s\n", linkdir, strerror (errno));
+                return -1;
+        }
+
+        respath = glfs_getcwd (fs, pathbuf, 4096);
+        fprintf (stdout, "getcwd() = %s\n", respath);
+
+        respath = glfs_realpath (fs, subdir, pathbuf);
+        if (respath) {
+                fprintf (stderr, "realpath(%s) worked unexpectedly: %s\n", subdir, respath);
+                return -1;
+        }
+
+        ret = glfs_mkdir (fs, subdir, 0755);
+        if (ret) {
+                fprintf (stderr, "mkdir(%s): %s\n", subdir, strerror (errno));
+                return -1;
+        }
+
+        respath = glfs_realpath (fs, subdir, pathbuf);
+        if (!respath) {
+                fprintf (stderr, "realpath(%s): %s\n", subdir, strerror (errno));
+        } else {
+                fprintf (stdout, "realpath(%s) = %s\n", subdir, respath);
+        }
+
+        ret = glfs_chdir (fs, subdir);
+        if (ret) {
+                fprintf (stderr, "chdir(%s): %s\n", subdir, strerror (errno));
+                return -1;
+        }
+
+        respath = glfs_getcwd (fs, pathbuf, 4096);
+        fprintf (stdout, "getcwd() = %s\n", respath);
+
+        respath = glfs_realpath (fs, "/linkdir/subdir", pathbuf);
+        if (!respath) {
+                fprintf (stderr, "realpath(/linkdir/subdir): %s\n", strerror (errno));
+        } else {
+                fprintf (stdout, "realpath(/linkdir/subdir) = %s\n", respath);
+        }
+
+        return 0;
+}
+
+#ifdef DEBUG
+static void
+peek_stat (struct stat *sb)
+{
+        printf ("Dumping stat information:\n");
+        printf ("File type:                ");
+
+        switch (sb->st_mode & S_IFMT) {
+                case S_IFBLK:  printf ("block device\n");            break;
+                case S_IFCHR:  printf ("character device\n");        break;
+                case S_IFDIR:  printf ("directory\n");               break;
+                case S_IFIFO:  printf ("FIFO/pipe\n");               break;
+                case S_IFLNK:  printf ("symlink\n");                 break;
+                case S_IFREG:  printf ("regular file\n");            break;
+                case S_IFSOCK: printf ("socket\n");                  break;
+                default:       printf ("unknown?\n");                break;
+        }
+
+        printf ("I-node number:            %ld\n", (long) sb->st_ino);
+
+        printf ("Mode:                     %lo (octal)\n",
+                (unsigned long) sb->st_mode);
+
+        printf ("Link count:               %ld\n", (long) sb->st_nlink);
+        printf ("Ownership:                UID=%ld   GID=%ld\n",
+                (long) sb->st_uid, (long) sb->st_gid);
+
+        printf ("Preferred I/O block size: %ld bytes\n",
+                (long) sb->st_blksize);
+        printf ("File size:                %lld bytes\n",
+                (long long) sb->st_size);
+        printf ("Blocks allocated:         %lld\n",
+                (long long) sb->st_blocks);
+
+        printf ("Last status change:       %s", ctime(&sb->st_ctime));
+        printf ("Last file access:         %s", ctime(&sb->st_atime));
+        printf ("Last file modification:   %s", ctime(&sb->st_mtime));
+
+        return;
+}
+
+static void
+peek_handle (unsigned char *glid)
+{
+        int i;
+
+        for (i = 0; i < GFAPI_HANDLE_LENGTH; i++)
+        {
+                printf (":%02x:", glid[i]);
+        }
+        printf ("\n");
+}
+#else /* DEBUG */
+static void
+peek_stat (struct stat *sb)
+{
+        return;
+}
+
+static void
+peek_handle (unsigned char *id)
+{
+        return;
+}
+#endif /* DEBUG */
+
+glfs_t    *fs = NULL;
+char      *full_parent_name = "/testdir", *parent_name = "testdir";
+
+void
+test_h_unlink (void)
+{
+        char               *my_dir = "unlinkdir";
+        char               *my_file = "file.txt";
+        char               *my_subdir = "dir1";
+        struct glfs_object *parent = NULL, *leaf = NULL, *dir = NULL,
+                           *subdir = NULL, *subleaf = NULL;
+        struct stat         sb;
+        int                 ret;
+
+        printf ("glfs_h_unlink tests: In Progress\n");
+
+        /* Prepare tests */
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dir = glfs_h_mkdir (fs, parent, my_dir, 0644, &sb);
+        if (dir == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, parent, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        leaf = glfs_h_creat (fs, dir, my_file, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        subdir = glfs_h_mkdir (fs, dir, my_subdir, 0644, &sb);
+        if (subdir == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_subdir, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        subleaf = glfs_h_creat (fs, subdir, my_file, O_CREAT, 0644, &sb);
+        if (subleaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, subdir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink non empty directory */
+        ret = glfs_h_unlink (fs, dir, my_subdir);
+        if ((ret && errno != ENOTEMPTY) || (ret == 0)) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking %s: it is non empty: %s\n",
+                         my_subdir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink regular file */
+        ret = glfs_h_unlink (fs, subdir, my_file);
+        if (ret) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking %s: from (%p),%s\n",
+                         my_file, subdir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink directory */
+        ret = glfs_h_unlink (fs, dir, my_subdir);
+        if (ret) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking %s: from (%p),%s\n",
+                         my_subdir, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink regular file */
+        ret = glfs_h_unlink (fs, dir, my_file);
+        if (ret) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking %s: from (%p),%s\n",
+                         my_file, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink non-existant regular file */
+        ret = glfs_h_unlink (fs, dir, my_file);
+        if ((ret && errno != ENOENT) || (ret == 0)) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking non-existant %s: invalid errno ,%d, %s\n",
+                         my_file, ret, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink non-existant directory */
+        ret = glfs_h_unlink (fs, dir, my_subdir);
+        if ((ret && errno != ENOENT) || (ret == 0)) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking non-existant %s:  invalid errno ,%d, %s\n",
+                         my_subdir, ret, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        /* unlink directory */
+        ret = glfs_h_unlink (fs, parent, my_dir);
+        if (ret) {
+                fprintf (stderr, "glfs_h_unlink: error unlinking %s: from (%p),%s\n",
+                         my_dir, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+
+        printf ("glfs_h_unlink tests: PASSED\n");
+
+out:
+        if (dir)
+                glfs_h_close (dir);
+        if (leaf)
+                glfs_h_close (leaf);
+        if (subdir)
+                glfs_h_close (subdir);
+        if (subleaf)
+                glfs_h_close (subleaf);
+        if (parent)
+                glfs_h_close (parent);
+
+        return;
+}
+
+void
+test_h_getsetattrs (void)
+{
+        char               *my_dir = "attrdir";
+        char               *my_file = "attrfile.txt";
+        struct glfs_object *parent = NULL, *leaf = NULL, *dir = NULL;
+        struct stat         sb, retsb;
+        int                 ret, valid;
+        struct timespec     timestamp;
+
+        printf("glfs_h_getattrs and setattrs tests: In Progress\n");
+
+        /* Prepare tests */
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dir = glfs_h_mkdir (fs, parent, my_dir, 0644, &sb);
+        if (dir == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, parent, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_creat (fs, dir, my_file, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, dir, strerror (errno));
+                printf ("glfs_h_unlink tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        ret = glfs_h_getattrs (fs, dir, &retsb);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_getattrs: error %s: from (%p),%s\n",
+                         my_dir, dir, strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&retsb);
+        /* TODO: Compare stat information */
+
+        retsb.st_mode = 00666;
+        retsb.st_uid = 1000;
+        retsb.st_gid = 1001;
+        ret = clock_gettime (CLOCK_REALTIME, &timestamp);
+        if(ret != 0) {
+                fprintf (stderr, "clock_gettime: error %s\n", strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+        retsb.st_atim = timestamp;
+        retsb.st_mtim = timestamp;
+        valid = GFAPI_SET_ATTR_MODE | GFAPI_SET_ATTR_UID | GFAPI_SET_ATTR_GID |
+        GFAPI_SET_ATTR_ATIME | GFAPI_SET_ATTR_MTIME;
+        peek_stat (&retsb);
+
+        ret = glfs_h_setattrs (fs, dir, &retsb, valid);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_setattrs: error %s: from (%p),%s\n",
+                         my_dir, dir, strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+
+        memset(&retsb, 0, sizeof (struct stat));
+        ret = glfs_h_stat (fs, dir, &retsb);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_stat: error %s: from (%p),%s\n",
+                         my_dir, dir, strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&retsb);
+
+        printf ("glfs_h_getattrs and setattrs tests: PASSED\n");
+out:
+        if (parent)
+                glfs_h_close (parent);
+        if (leaf)
+                glfs_h_close (leaf);
+        if (dir)
+                glfs_h_close (dir);
+
+        return;
+}
+
+void
+test_h_truncate (void)
+{
+        char               *my_dir = "truncatedir";
+        char               *my_file = "file.txt";
+        struct glfs_object *root = NULL, *parent = NULL, *leaf = NULL;
+        struct stat         sb;
+        glfs_fd_t          *fd = NULL;
+        char                buf[32];
+        off_t               offset = 0;
+        int                 ret = 0;
+
+        printf("glfs_h_truncate tests: In Progress\n");
+
+        /* Prepare tests */
+        root = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (root == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        parent = glfs_h_mkdir (fs, root, my_dir, 0644, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, root, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_creat (fs, parent, my_file, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        fd = glfs_h_open (fs, leaf, O_RDWR);
+        if (fd == NULL) {
+                fprintf (stderr, "glfs_h_open: error on open of %s: %s\n",
+                         my_file, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+
+        memcpy (buf, "abcdefghijklmnopqrstuvwxyz012345", 32);
+        ret = glfs_write (fd, buf, 32, 0);
+
+        /* run tests */
+        /* truncate lower */
+        offset = 30;
+        ret = glfs_h_truncate (fs, leaf, offset);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_truncate: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        ret = glfs_h_getattrs (fs, leaf, &sb);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_getattrs: error for %s (%p),%s\n",
+                         my_file, leaf, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        if (sb.st_size != offset) {
+                fprintf (stderr, "glfs_h_truncate: post size mismatch\n");
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+
+        /* truncate higher */
+        offset = 32;
+        ret = glfs_h_truncate (fs, leaf, offset);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_truncate: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        ret = glfs_h_getattrs (fs, leaf, &sb);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_getattrs: error for %s (%p),%s\n",
+                         my_file, leaf, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        if (sb.st_size != offset) {
+                fprintf (stderr, "glfs_h_truncate: post size mismatch\n");
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+
+        /* truncate equal */
+        offset = 30;
+        ret = glfs_h_truncate (fs, leaf, offset);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_truncate: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        ret = glfs_h_getattrs (fs, leaf, &sb);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_getattrs: error for %s (%p),%s\n",
+                         my_file, leaf, strerror (errno));
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+        if (sb.st_size != offset) {
+                fprintf (stderr, "glfs_h_truncate: post size mismatch\n");
+                printf ("glfs_h_truncate tests: FAILED\n");
+                goto out;
+        }
+
+        printf ("glfs_h_truncate tests: PASSED\n");
+out:
+        if (fd)
+                glfs_close (fd);
+        if (root)
+                glfs_h_close (root);
+        if (parent)
+                glfs_h_close (parent);
+        if (leaf)
+                glfs_h_close (leaf);
+
+        return;
+}
+
+void
+test_h_links (void)
+{
+        char               *my_dir = "linkdir";
+        char               *my_file = "file.txt";
+        char               *my_symlnk = "slnk.txt";
+        char               *my_lnk = "lnk.txt";
+        char               *linksrc_dir = "dir1";
+        char               *linktgt_dir = "dir2";
+        struct glfs_object *root = NULL, *parent = NULL, *leaf = NULL,
+                           *dirsrc = NULL, *dirtgt = NULL, *dleaf = NULL;
+        struct glfs_object *ln1 = NULL;
+        struct stat         sb;
+        int                 ret;
+        char               *buf = NULL;
+
+        printf("glfs_h_link(s) tests: In Progress\n");
+
+        /* Prepare tests */
+        root = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (root == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        parent = glfs_h_mkdir (fs, root, my_dir, 0644, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, root, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_creat (fs, parent, my_file, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dirsrc = glfs_h_mkdir (fs, parent, linksrc_dir, 0644, &sb);
+        if (dirsrc == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         linksrc_dir, parent, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dirtgt = glfs_h_mkdir (fs, parent, linktgt_dir, 0644, &sb);
+        if (dirtgt == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         linktgt_dir, parent, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dleaf = glfs_h_creat (fs, dirsrc, my_file, O_CREAT, 0644, &sb);
+        if (dleaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, dirsrc, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* run tests */
+        /* sym link: /testdir/linkdir/file.txt to ./slnk.txt */
+        ln1 = glfs_h_symlink (fs, parent, my_symlnk, "./file.txt", &sb);
+        if (ln1 == NULL) {
+                fprintf (stderr, "glfs_h_symlink: error creating %s: from (%p),%s\n",
+                         my_symlnk, parent, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        buf = calloc (1024, sizeof(char));
+        if (buf == NULL) {
+                fprintf (stderr, "Error allocating memory\n");
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+
+        ret = glfs_h_readlink (fs, ln1, buf, 1024);
+        if (ret <= 0) {
+                fprintf (stderr, "glfs_h_readlink: error reading %s: from (%p),%s\n",
+                         my_symlnk, ln1, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        if (!(strncmp (buf, my_symlnk, strlen (my_symlnk)))) {
+                fprintf (stderr, "glfs_h_readlink: error mismatch in link name: actual %s: retrieved %s\n",
+                         my_symlnk, buf);
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+
+        /* link: /testdir/linkdir/file.txt to ./lnk.txt */
+        ret = glfs_h_link (fs, leaf, parent, my_lnk);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_link: error creating %s: from (%p),%s\n",
+                         my_lnk, parent, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        /* TODO: Should write content to a file and read from the link */
+
+        /* link: /testdir/linkdir/dir1/file.txt to ../dir2/slnk.txt */
+        ret = glfs_h_link (fs, dleaf, dirtgt, my_lnk);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_link: error creating %s: from (%p),%s\n",
+                         my_lnk, dirtgt, strerror (errno));
+                printf ("glfs_h_link(s) tests: FAILED\n");
+                goto out;
+        }
+        /* TODO: Should write content to a file and read from the link */
+
+        printf ("glfs_h_link(s) tests: PASSED\n");
+
+out:
+        if (root)
+                glfs_h_close (root);
+        if (parent)
+                glfs_h_close (parent);
+        if (leaf)
+                glfs_h_close (leaf);
+        if (dirsrc)
+                glfs_h_close (dirsrc);
+        if (dirtgt)
+                glfs_h_close (dirtgt);
+        if (dleaf)
+                glfs_h_close (dleaf);
+        if (ln1)
+                glfs_h_close (ln1);
+        if (buf)
+                free (buf);
+
+        return;
+}
+
+void
+test_h_rename (void)
+{
+        char               *my_dir = "renamedir";
+        char               *my_file = "file.txt";
+        char               *src_dir = "dir1";
+        char               *tgt_dir = "dir2";
+        struct glfs_object *root = NULL, *parent = NULL, *leaf = NULL,
+                           *dirsrc = NULL, *dirtgt = NULL, *dleaf = NULL;
+        struct stat         sb;
+        int                 ret;
+
+        printf("glfs_h_rename tests: In Progress\n");
+
+        /* Prepare tests */
+        root = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (root == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        parent = glfs_h_mkdir (fs, root, my_dir, 0644, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, root, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_creat (fs, parent, my_file, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, parent, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dirsrc = glfs_h_mkdir (fs, parent, src_dir, 0644, &sb);
+        if (dirsrc == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         src_dir, parent, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dirtgt = glfs_h_mkdir (fs, parent, tgt_dir, 0644, &sb);
+        if (dirtgt == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         tgt_dir, parent, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        dleaf = glfs_h_creat (fs, dirsrc, my_file, O_CREAT, 0644, &sb);
+        if (dleaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                         my_file, dirsrc, strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* run tests */
+        /* Rename file.txt -> file1.txt */
+        ret = glfs_h_rename (fs, parent, "file.txt", parent, "file1.txt");
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_rename: error renaming %s to %s (%s)\n",
+                         "file.txt", "file1.txt", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename dir1/file.txt -> file.txt */
+        ret = glfs_h_rename (fs, dirsrc, "file.txt", parent, "file.txt");
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_rename: error renaming %s/%s to %s (%s)\n",
+                         src_dir, "file.txt", "file.txt", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename file1.txt -> file.txt (exists) */
+        ret = glfs_h_rename (fs, parent, "file1.txt", parent, "file.txt");
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_rename: error renaming %s to %s (%s)\n",
+                         "file.txt", "file.txt", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename dir1 -> dir3 */
+        ret = glfs_h_rename (fs, parent, "dir1", parent, "dir3");
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_rename: error renaming %s to %s (%s)\n",
+                         "dir1", "dir3", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename dir2 ->dir3 (exists) */
+        ret = glfs_h_rename (fs, parent, "dir2", parent, "dir3");
+        if (ret != 0) {
+                fprintf (stderr, "glfs_h_rename: error renaming %s to %s (%s)\n",
+                         "dir2", "dir3", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename file.txt -> dir3 (fail) */
+        ret = glfs_h_rename (fs, parent, "file.txt", parent, "dir3");
+        if (ret == 0) {
+                fprintf (stderr, "glfs_h_rename: NO error renaming %s to %s (%s)\n",
+                         "file.txt", "dir3", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        /* rename dir3 -> file.txt (fail) */
+        ret = glfs_h_rename (fs, parent, "dir3", parent, "file.txt");
+        if (ret == 0) {
+                fprintf (stderr, "glfs_h_rename: NO error renaming %s to %s (%s)\n",
+                         "dir3", "file.txt", strerror (errno));
+                printf ("glfs_h_rename tests: FAILED\n");
+                goto out;
+        }
+
+        printf ("glfs_h_rename tests: PASSED\n");
+
+out:
+        if (root)
+                glfs_h_close (root);
+        if (parent)
+                glfs_h_close (parent);
+        if (leaf)
+                glfs_h_close (leaf);
+        if (dirsrc)
+                glfs_h_close (dirsrc);
+        if (dirtgt)
+                glfs_h_close (dirtgt);
+        if (dleaf)
+                glfs_h_close (dleaf);
+
+        return;
+}
+
+void
+assimilatetime (struct timespec *ts, struct timespec ts_st,
+                struct timespec ts_ed)
+{
+        if ((ts_ed.tv_nsec - ts_st.tv_nsec) < 0) {
+                ts->tv_sec += ts_ed.tv_sec - ts_st.tv_sec - 1;
+                ts->tv_nsec += 1000000000 + ts_ed.tv_nsec - ts_st.tv_nsec;
+        } else {
+                ts->tv_sec += ts_ed.tv_sec - ts_st.tv_sec;
+                ts->tv_nsec += ts_ed.tv_nsec - ts_st.tv_nsec;
+        }
+
+        if (ts->tv_nsec > 1000000000) {
+                ts->tv_nsec = ts->tv_nsec - 1000000000;
+                ts->tv_sec += 1;
+        }
+
+        return;
+}
+
+#define MAX_FILES_CREATE 10
+#define MAXPATHNAME      512
+void
+test_h_performance (void)
+{
+        char               *my_dir = "perftest",
+                           *full_dir_path="/testdir/perftest";
+        char               *my_file = "file_", my_file_name[MAXPATHNAME];
+        struct glfs_object *parent = NULL, *leaf = NULL, *dir = NULL;
+        struct stat         sb;
+        int                 ret, i;
+        struct glfs_fd     *fd;
+        struct timespec     c_ts = {0, 0}, c_ts_st, c_ts_ed;
+        struct timespec     o_ts = {0, 0}, o_ts_st, o_ts_ed;
+
+        printf("glfs_h_performance tests: In Progress\n");
+
+        /* Prepare tests */
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, NULL, strerror (errno));
+                printf ("glfs_h_performance tests: FAILED\n");
+                goto out;
+        }
+
+        dir = glfs_h_mkdir (fs, parent, my_dir, 0644, &sb);
+        if (dir == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, parent, strerror (errno));
+                printf ("glfs_h_performance tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* create performance */
+        ret = clock_gettime (CLOCK_REALTIME, &o_ts_st);
+        if(ret != 0) {
+                fprintf (stderr, "clock_gettime: error %s\n", strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+
+        for (i = 0; i < MAX_FILES_CREATE; i++) {
+                sprintf (my_file_name, "%s%d", my_file, i);
+
+                ret = clock_gettime (CLOCK_REALTIME, &c_ts_st);
+                if(ret != 0) {
+                        fprintf (stderr, "clock_gettime: error %s\n",
+                                 strerror (errno));
+                        printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                        goto out;
+                }
+
+                leaf = glfs_h_lookupat (fs, dir, my_file_name, &sb);
+                if (leaf != NULL) {
+                        fprintf (stderr, "glfs_h_lookup: exists %s\n",
+                                 my_file_name);
+                        printf ("glfs_h_performance tests: FAILED\n");
+                        goto out;
+                }
+
+                leaf = glfs_h_creat (fs, dir, my_file_name, O_CREAT, 0644, &sb);
+                if (leaf == NULL) {
+                        fprintf (stderr, "glfs_h_creat: error creating %s: from (%p),%s\n",
+                                 my_file, dir, strerror (errno));
+                        printf ("glfs_h_performance tests: FAILED\n");
+                        goto out;
+                }
+
+                ret = clock_gettime (CLOCK_REALTIME, &c_ts_ed);
+                if(ret != 0) {
+                        fprintf (stderr, "clock_gettime: error %s\n",
+                                 strerror (errno));
+                        printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                        goto out;
+                }
+
+                assimilatetime (&c_ts, c_ts_st, c_ts_ed);
+                glfs_h_close (leaf); leaf = NULL;
+        }
+
+        ret = clock_gettime (CLOCK_REALTIME, &o_ts_ed);
+        if(ret != 0) {
+                fprintf (stderr, "clock_gettime: error %s\n", strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+
+        assimilatetime (&o_ts, o_ts_st, o_ts_ed);
+
+        printf ("Creation performance (handle based):\n\t# empty files:%d\n",
+                MAX_FILES_CREATE);
+        printf ("\tOverall time:\n\t\tSecs:%ld\n\t\tnSecs:%ld\n",
+                o_ts.tv_sec, o_ts.tv_nsec);
+        printf ("\tcreate call time time:\n\t\tSecs:%ld\n\t\tnSecs:%ld\n",
+                c_ts.tv_sec, c_ts.tv_nsec);
+
+        /* create using path */
+        c_ts.tv_sec = o_ts.tv_sec = 0;
+        c_ts.tv_nsec = o_ts.tv_nsec = 0;
+
+        sprintf (my_file_name, "%s1", full_dir_path);
+        ret = glfs_mkdir (fs, my_file_name, 0644);
+        if (ret != 0) {
+                fprintf (stderr, "glfs_mkdir: error creating %s: from (%p),%s\n",
+                         my_dir, parent, strerror (errno));
+                printf ("glfs_h_performance tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        ret = clock_gettime (CLOCK_REALTIME, &o_ts_st);
+        if(ret != 0) {
+                fprintf (stderr, "clock_gettime: error %s\n", strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+
+        for (i = 0; i < MAX_FILES_CREATE; i++) {
+                sprintf (my_file_name, "%s1/%sn%d", full_dir_path, my_file, i);
+
+                ret = clock_gettime (CLOCK_REALTIME, &c_ts_st);
+                if(ret != 0) {
+                        fprintf (stderr, "clock_gettime: error %s\n",
+                                 strerror (errno));
+                        printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                        goto out;
+                }
+
+                ret = glfs_stat (fs, my_file_name, &sb);
+                if (ret == 0) {
+                        fprintf (stderr, "glfs_stat: exists %s\n",
+                                 my_file_name);
+                        printf ("glfs_h_performance tests: FAILED\n");
+                        goto out;
+                }
+
+                fd = glfs_creat (fs, my_file_name, O_CREAT, 0644);
+                if (fd == NULL) {
+                        fprintf (stderr, "glfs_creat: error creating %s: from (%p),%s\n",
+                                 my_file, dir, strerror (errno));
+                        printf ("glfs_h_performance tests: FAILED\n");
+                        goto out;
+                }
+
+                ret = clock_gettime (CLOCK_REALTIME, &c_ts_ed);
+                if(ret != 0) {
+                        fprintf (stderr, "clock_gettime: error %s\n",
+                                 strerror (errno));
+                        printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                        goto out;
+                }
+
+                assimilatetime (&c_ts, c_ts_st, c_ts_ed);
+                glfs_close (fd);
+        }
+
+        ret = clock_gettime (CLOCK_REALTIME, &o_ts_ed);
+        if(ret != 0) {
+                fprintf (stderr, "clock_gettime: error %s\n", strerror (errno));
+                printf ("glfs_h_getattrs and setattrs tests: FAILED\n");
+                goto out;
+        }
+
+        assimilatetime (&o_ts, o_ts_st, o_ts_ed);
+
+        printf ("Creation performance (path based):\n\t# empty files:%d\n",
+                MAX_FILES_CREATE);
+        printf ("\tOverall time:\n\t\tSecs:%ld\n\t\tnSecs:%ld\n",
+                o_ts.tv_sec, o_ts.tv_nsec);
+        printf ("\tcreate call time time:\n\t\tSecs:%ld\n\t\tnSecs:%ld\n",
+                c_ts.tv_sec, c_ts.tv_nsec);
+out:
+        return;
+}
+
+int
+test_handleops (int argc, char *argv[])
+{
+        int                 ret = 0;
+        glfs_fd_t          *fd = NULL;
+        struct stat         sb = {0, };
+        struct glfs_object *root = NULL, *parent = NULL, *leaf = NULL,
+                           *tmp = NULL;
+        char                readbuf[32], writebuf[32];
+        unsigned char       leaf_handle[GFAPI_HANDLE_LENGTH];
+
+        char *full_leaf_name = "/testdir/testfile.txt",
+             *leaf_name = "testfile.txt",
+             *relative_leaf_name = "testdir/testfile.txt";
+        char *leaf_name1 = "testfile1.txt";
+        char *full_newparent_name = "/testdir/dir1",
+             *newparent_name = "dir1";
+        char *full_newnod_name = "/testdir/nod1",
+             *newnod_name = "nod1";
+
+        /* Initialize test area */
+        ret = glfs_mkdir (fs, full_parent_name, 0644);
+        if (ret != 0 && errno != EEXIST) {
+                fprintf (stderr, "%s: (%p) %s\n", full_parent_name, fd,
+                        strerror (errno));
+                printf ("Test initialization failed on volume %s\n", argv[1]);
+                goto out;
+        }
+        else if (ret != 0) {
+                printf ("Found test directory %s to be existing\n",
+                        full_parent_name);
+                printf ("Cleanup test directory and restart tests\n");
+                goto out;
+        }
+
+        fd = glfs_creat (fs, full_leaf_name, O_CREAT, 0644);
+        if (fd == NULL) {
+                fprintf (stderr, "%s: (%p) %s\n", full_leaf_name, fd,
+                        strerror (errno));
+                printf ("Test initialization failed on volume %s\n", argv[1]);
+                goto out;
+        }
+        glfs_close (fd);
+
+        printf ("Initialized the test area, within volume %s\n", argv[1]);
+
+        /* Handle based APIs test area */
+
+        /* glfs_lookupat test */
+        printf ("glfs_h_lookupat tests: In Progress\n");
+        /* start at root of the volume */
+        root = glfs_h_lookupat (fs, NULL, "/", &sb);
+        if (root == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         "/", NULL, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* lookup a parent within root */
+        parent = glfs_h_lookupat (fs, root, parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         parent_name, root, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* lookup a leaf/child within the parent */
+        leaf = glfs_h_lookupat (fs, parent, leaf_name, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         leaf_name, parent, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* reset */
+        glfs_h_close (root); root = NULL;
+        glfs_h_close (leaf); leaf = NULL;
+        glfs_h_close (parent); parent = NULL;
+
+        /* check absolute paths */
+        root = glfs_h_lookupat (fs, NULL, "/", &sb);
+        if (root == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         "/", NULL, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, root, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_lookupat (fs, NULL, full_leaf_name, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_leaf_name, parent, strerror (errno));
+                printf ("glfs_h_lookupat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* reset */
+        glfs_h_close (leaf); leaf = NULL;
+
+        /* check multiple component paths */
+        leaf = glfs_h_lookupat (fs, root, relative_leaf_name, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         relative_leaf_name, parent, strerror (errno));
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* reset */
+        glfs_h_close (root); root = NULL;
+        glfs_h_close (parent); parent = NULL;
+
+        /* check symlinks in path */
+
+        /* TODO: -ve test cases */
+        /* parent invalid
+        * path invalid
+        * path does not exist after some components
+        * no parent, but relative path
+        * parent and full path? -ve?
+        */
+
+        printf ("glfs_h_lookupat tests: PASSED\n");
+
+        /* glfs_openat test */
+        printf ("glfs_h_open tests: In Progress\n");
+        fd = glfs_h_open (fs, leaf, O_RDWR);
+        if (fd == NULL) {
+                fprintf (stderr, "glfs_h_open: error on open of %s: %s\n",
+                         full_leaf_name, strerror (errno));
+                printf ("glfs_h_open tests: FAILED\n");
+                goto out;
+        }
+
+        /* test read/write based on fd */
+        memcpy (writebuf, "abcdefghijklmnopqrstuvwxyz012345", 32);
+        ret = glfs_write (fd, writebuf, 32, 0);
+
+        glfs_lseek (fd, 0, SEEK_SET);
+
+        ret = glfs_read (fd, readbuf, 32, 0);
+        if (memcmp (readbuf, writebuf, 32)) {
+                printf ("Failed to read what I wrote: %s %s\n", readbuf,
+                        writebuf);
+                glfs_close (fd);
+                printf ("glfs_h_open tests: FAILED\n");
+                goto out;
+        }
+
+        glfs_h_close (leaf); leaf = NULL;
+        glfs_close (fd);
+
+        printf ("glfs_h_open tests: PASSED\n");
+
+        /* Create tests */
+        printf ("glfs_h_creat tests: In Progress\n");
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, root, strerror (errno));
+                printf ("glfs_h_creat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_creat (fs, parent, leaf_name1, O_CREAT, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_creat: error on create of %s: from (%p),%s\n",
+                         leaf_name1, parent, strerror (errno));
+                printf ("glfs_h_creat tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        glfs_h_close (leaf); leaf = NULL;
+
+        leaf = glfs_h_creat (fs, parent, leaf_name1, O_CREAT | O_EXCL, 0644,
+                            &sb);
+        if (leaf != NULL || errno != EEXIST) {
+                fprintf (stderr, "glfs_h_creat: existing file, leaf = (%p), errno = %s\n",
+                        leaf, strerror (errno));
+                printf ("glfs_h_creat tests: FAILED\n");
+                if (leaf != NULL) {
+                        glfs_h_close (leaf); leaf = NULL;
+                }
+        }
+
+        tmp = glfs_h_creat (fs, root, parent_name, O_CREAT, 0644, &sb);
+        if (tmp != NULL || !(errno == EISDIR || errno == EINVAL)) {
+                fprintf (stderr, "glfs_h_creat: dir create, tmp = (%p), errno = %s\n",
+                        leaf, strerror (errno));
+                printf ("glfs_h_creat tests: FAILED\n");
+                if (tmp != NULL) {
+                        glfs_h_close (tmp); tmp = NULL;
+                }
+        }
+
+        /* TODO: Other combinations and -ve cases as applicable */
+        printf ("glfs_h_creat tests: PASSED\n");
+
+        /* extract handle and create from handle test */
+        printf ("glfs_h_extract_handle and glfs_h_create_from_handle tests: In Progress\n");
+        /* TODO: Change the lookup to creat below for a GIFD recovery falure,
+         * that needs to be fixed */
+        leaf = glfs_h_lookupat (fs, parent, leaf_name1, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         leaf_name1, parent, strerror (errno));
+                printf ("glfs_h_extract_handle tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        ret = glfs_h_extract_handle (leaf, leaf_handle,
+                                             GFAPI_HANDLE_LENGTH);
+        if (ret < 0) {
+                fprintf (stderr, "glfs_h_extract_handle: error extracting handle of %s: %s\n",
+                         full_leaf_name, strerror (errno));
+                printf ("glfs_h_extract_handle tests: FAILED\n");
+                goto out;
+        }
+        peek_handle (leaf_handle);
+
+        glfs_h_close (leaf); leaf = NULL;
+
+        leaf = glfs_h_create_from_handle (fs, leaf_handle, GFAPI_HANDLE_LENGTH,
+                                          &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_create_from_handle: error on create of %s: from (%p),%s\n",
+                         leaf_name1, leaf_handle, strerror (errno));
+                printf ("glfs_h_create_from_handle tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        fd = glfs_h_open (fs, leaf, O_RDWR);
+        if (fd == NULL) {
+                fprintf (stderr, "glfs_h_open: error on open of %s: %s\n",
+                         full_leaf_name, strerror (errno));
+                printf ("glfs_h_create_from_handle tests: FAILED\n");
+                goto out;
+        }
+
+        /* test read/write based on fd */
+        memcpy (writebuf, "abcdefghijklmnopqrstuvwxyz012345", 32);
+        ret = glfs_write (fd, writebuf, 32, 0);
+
+        glfs_lseek (fd, 0, SEEK_SET);
+
+        ret = glfs_read (fd, readbuf, 32, 0);
+        if (memcmp (readbuf, writebuf, 32)) {
+                printf ("Failed to read what I wrote: %s %s\n", writebuf,
+                        writebuf);
+                printf ("glfs_h_create_from_handle tests: FAILED\n");
+                glfs_close (fd);
+                goto out;
+        }
+
+        glfs_close (fd);
+        glfs_h_close (leaf); leaf = NULL;
+        glfs_h_close (parent); parent = NULL;
+
+        printf ("glfs_h_extract_handle and glfs_h_create_from_handle tests: PASSED\n");
+
+        /* Mkdir tests */
+        printf ("glfs_h_mkdir tests: In Progress\n");
+
+        ret = glfs_rmdir (fs, full_newparent_name);
+        if (ret && errno != ENOENT) {
+                fprintf (stderr, "glfs_rmdir: Failed for %s: %s\n",
+                         full_newparent_name, strerror (errno));
+                printf ("glfs_h_mkdir tests: FAILED\n");
+                goto out;
+        }
+
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, root, strerror (errno));
+                printf ("glfs_h_mkdir tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_mkdir (fs, parent, newparent_name, 0644, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error on mkdir of %s: from (%p),%s\n",
+                         newparent_name, parent, strerror (errno));
+                printf ("glfs_h_mkdir tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        glfs_h_close (leaf); leaf = NULL;
+
+        leaf = glfs_h_mkdir (fs, parent, newparent_name, 0644, &sb);
+        if (leaf != NULL || errno != EEXIST) {
+                fprintf (stderr, "glfs_h_mkdir: existing directory, leaf = (%p), errno = %s\n",
+                         leaf, strerror (errno));
+                printf ("glfs_h_mkdir tests: FAILED\n");
+                if (leaf != NULL) {
+                        glfs_h_close (leaf); leaf = NULL;
+                }
+        }
+
+        glfs_h_close (parent); parent = NULL;
+
+        printf ("glfs_h_mkdir tests: PASSED\n");
+
+        /* Mknod tests */
+        printf ("glfs_h_mknod tests: In Progress\n");
+        ret = glfs_unlink (fs, full_newnod_name);
+        if (ret && errno != ENOENT) {
+                fprintf (stderr, "glfs_unlink: Failed for %s: %s\n",
+                         full_newnod_name, strerror (errno));
+                printf ("glfs_h_mknod tests: FAILED\n");
+                goto out;
+        }
+
+        parent = glfs_h_lookupat (fs, NULL, full_parent_name, &sb);
+        if (parent == NULL) {
+                fprintf (stderr, "glfs_h_lookupat: error on lookup of %s: from (%p),%s\n",
+                         full_parent_name, root, strerror (errno));
+                printf ("glfs_h_mknod tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        leaf = glfs_h_mknod (fs, parent, newnod_name, S_IFIFO, 0, &sb);
+        if (leaf == NULL) {
+                fprintf (stderr, "glfs_h_mkdir: error on mkdir of %s: from (%p),%s\n",
+                         newnod_name, parent, strerror (errno));
+                printf ("glfs_h_mknod tests: FAILED\n");
+                goto out;
+        }
+        peek_stat (&sb);
+
+        /* TODO: creat op on a FIFO node hangs, need to check and fix
+        tmp = glfs_h_creat (fs, parent, newnod_name, O_CREAT, 0644, &sb);
+        if (tmp != NULL || errno != EINVAL) {
+                fprintf (stderr, "glfs_h_creat: node create, tmp = (%p), errno = %s\n",
+                        tmp, strerror (errno));
+                printf ("glfs_h_creat/mknod tests: FAILED\n");
+                if (tmp != NULL) {
+                        glfs_h_close(tmp); tmp = NULL;
+                }
+        } */
+
+        glfs_h_close (leaf); leaf = NULL;
+
+        leaf = glfs_h_mknod (fs, parent, newnod_name, 0644, 0, &sb);
+        if (leaf != NULL || errno != EEXIST) {
+                fprintf (stderr, "glfs_h_mknod: existing node, leaf = (%p), errno = %s\n",
+                         leaf, strerror (errno));
+                printf ("glfs_h_mknod tests: FAILED\n");
+                if (leaf != NULL) {
+                        glfs_h_close (leaf); leaf = NULL;
+                }
+        }
+
+        glfs_h_close (parent); parent = NULL;
+
+        printf ("glfs_h_mknod tests: PASSED\n");
+
+        /* unlink tests */
+        test_h_unlink ();
+
+        /* TODO: opendir tests */
+
+        /* getattr tests */
+        test_h_getsetattrs ();
+
+        /* TODO: setattr tests */
+
+        /* truncate tests */
+        test_h_truncate();
+
+        /* link tests */
+        test_h_links ();
+
+        /* rename tests */
+        test_h_rename ();
+
+        /* performance tests */
+        test_h_performance ();
+
+        /* END: New APIs test area */
+
+out:
+        /* Cleanup glfs handles */
+        if (root)
+                glfs_h_close (root);
+        if (parent)
+                glfs_h_close (parent);
+        if (leaf)
+                glfs_h_close (leaf);
+
+        return ret;
+}
+
+int
 main (int argc, char *argv[])
 {
-	glfs_t    *fs = NULL;
-	glfs_t    *fs2 = NULL;
-	int        ret = 0;
-	glfs_fd_t *fd = NULL;
-	glfs_fd_t *fd2 = NULL;
-	struct stat sb = {0, };
-	char       readbuf[32];
-	char       writebuf[32];
+        glfs_t    *fs2 = NULL;
+        int        ret = 0;
+        glfs_fd_t *fd = NULL;
+        glfs_fd_t *fd2 = NULL;
+        struct stat sb = {0, };
+        char       readbuf[32];
+        char       writebuf[32];
+
+        char      *filename = "/filename2";
+
+        if (argc != 3) {
+                printf ("Expect following args\n\t%s <volname> <hostname>\n", argv[0]);
+                return -1;
+        }
 
-	char      *filename = "/filename2";
+        fs = glfs_new (argv[1]);
+        if (!fs) {
+                fprintf (stderr, "glfs_new: returned NULL\n");
+                return 1;
+        }
 
-	fs = glfs_new ("iops");
-	if (!fs) {
-		fprintf (stderr, "glfs_new: returned NULL\n");
-		return 1;
-	}
+//      ret = glfs_set_volfile (fs, "/tmp/posix.vol");
 
-//	ret = glfs_set_volfile (fs, "/tmp/posix.vol");
+        ret = glfs_set_volfile_server (fs, "tcp", argv[2], 24007);
 
-	ret = glfs_set_volfile_server (fs, "tcp", "localhost", 24007);
+//      ret = glfs_set_volfile_server (fs, "unix", "/tmp/gluster.sock", 0);
 
-//	ret = glfs_set_volfile_server (fs, "unix", "/tmp/gluster.sock", 0);
+        ret = glfs_set_logging (fs, "/dev/stderr", 7);
 
-	ret = glfs_set_logging (fs, "/dev/stderr", 7);
+        ret = glfs_init (fs);
 
-	ret = glfs_init (fs);
+        fprintf (stderr, "glfs_init: returned %d\n", ret);
 
-	fprintf (stderr, "glfs_init: returned %d\n", ret);
+        sleep (2);
 
-	sleep (2);
+        fs2 = glfs_new (argv[1]);
+        if (!fs2) {
+                fprintf (stderr, "glfs_new: returned NULL\n");
+                return 1;
+        }
 
-	fs2 = glfs_new ("iops");
-	if (!fs2) {
-		fprintf (stderr, "glfs_new: returned NULL\n");
-		return 1;
-	}
 
+//      ret = glfs_set_volfile (fs2, "/tmp/posix.vol");
 
-//	ret = glfs_set_volfile (fs2, "/tmp/posix.vol");
+        ret = glfs_set_volfile_server (fs2, "tcp", argv[2], 24007);
 
-	ret = glfs_set_volfile_server (fs2, "tcp", "localhost", 24007);
+        ret = glfs_set_logging (fs2, "/dev/stderr", 7);
 
-	ret = glfs_set_logging (fs2, "/dev/stderr", 7);
+        ret = glfs_init (fs2);
 
-	ret = glfs_init (fs2);
+        fprintf (stderr, "glfs_init: returned %d\n", ret);
 
-	fprintf (stderr, "glfs_init: returned %d\n", ret);
+        ret = glfs_lstat (fs, filename, &sb);
+        fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
 
-	ret = glfs_lstat (fs, filename, &sb);
-	fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
+        fd = glfs_creat (fs, filename, O_RDWR, 0644);
+        fprintf (stderr, "%s: (%p) %s\n", filename, fd, strerror (errno));
 
-	fd = glfs_creat (fs, filename, O_RDWR, 0644);
-	fprintf (stderr, "%s: (%p) %s\n", filename, fd, strerror (errno));
+        fd2 = glfs_open (fs2, filename, O_RDWR);
+        fprintf (stderr, "%s: (%p) %s\n", filename, fd, strerror (errno));
 
-	fd2 = glfs_open (fs2, filename, O_RDWR);
-	fprintf (stderr, "%s: (%p) %s\n", filename, fd, strerror (errno));
+        sprintf (writebuf, "hi there\n");
+        ret = glfs_write (fd, writebuf, 32, 0);
 
-	sprintf (writebuf, "hi there\n");
-	ret = glfs_write (fd, writebuf, 32, 0);
+        glfs_lseek (fd2, 0, SEEK_SET);
 
-	glfs_lseek (fd2, 0, SEEK_SET);
+        ret = glfs_read (fd2, readbuf, 32, 0);
 
-	ret = glfs_read (fd2, readbuf, 32, 0);
+        printf ("read %d, %s", ret, readbuf);
 
-	printf ("read %d, %s", ret, readbuf);
+        glfs_close (fd);
+        glfs_close (fd2);
 
-	glfs_close (fd);
-	glfs_close (fd2);
+        filename = "/filename3";
+        ret = glfs_mknod (fs, filename, S_IFIFO, 0);
+        fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
 
-	filename = "/filename3";
-	ret = glfs_mknod (fs, filename, S_IFIFO, 0);
-	fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
+        ret = glfs_lstat (fs, filename, &sb);
+        fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
 
-	ret = glfs_lstat (fs, filename, &sb);
-	fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
 
+        ret = glfs_rename (fs, filename, "/filename4");
+        fprintf (stderr, "rename(%s): (%d) %s\n", filename, ret,
+                 strerror (errno));
 
-	ret = glfs_rename (fs, filename, "/filename4");
-	fprintf (stderr, "rename(%s): (%d) %s\n", filename, ret,
-		 strerror (errno));
+        ret = glfs_unlink (fs, "/filename4");
+        fprintf (stderr, "unlink(%s): (%d) %s\n", "/filename4", ret,
+                 strerror (errno));
 
-	ret = glfs_unlink (fs, "/filename4");
-	fprintf (stderr, "unlink(%s): (%d) %s\n", "/filename4", ret,
-		 strerror (errno));
+        filename = "/dirname2";
+        ret = glfs_mkdir (fs, filename, 0);
+        fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
 
-	filename = "/dirname2";
-	ret = glfs_mkdir (fs, filename, 0);
-	fprintf (stderr, "%s: (%d) %s\n", filename, ret, strerror (errno));
+        ret = glfs_lstat (fs, filename, &sb);
+        fprintf (stderr, "lstat(%s): (%d) %s\n", filename, ret, strerror (errno));
 
-	ret = glfs_lstat (fs, filename, &sb);
-	fprintf (stderr, "lstat(%s): (%d) %s\n", filename, ret, strerror (errno));
+        ret = glfs_rmdir (fs, filename);
+        fprintf (stderr, "rmdir(%s): (%d) %s\n", filename, ret, strerror (errno));
 
-	ret = glfs_rmdir (fs, filename);
-	fprintf (stderr, "rmdir(%s): (%d) %s\n", filename, ret, strerror (errno));
+        test_dirops (fs);
 
-	test_dirops (fs);
+        test_xattr (fs);
 
-	test_xattr (fs);
+        test_chdir (fs);
 
-	// done
+        test_handleops (argc, argv);
+        // done
 
-	glfs_fini (fs);
-	glfs_fini (fs2);
+        glfs_fini (fs);
+        glfs_fini (fs2);
 
-	return ret;
+        return ret;
 }
diff --git a/api/examples/setup.py.in b/api/examples/setup.py.in
new file mode 100644
index 000000000..44b738094
--- /dev/null
+++ b/api/examples/setup.py.in
@@ -0,0 +1,29 @@
+from distutils.core import setup
+
+# generate a __init__.py for the package namespace
+fo = open('__init__.py', 'w')
+fo.write('__version__ = "@PACKAGE_VERSION@"\n')
+fo.close()
+
+DESC = """GlusterFS is a clustered file-system capable of scaling to
+several petabytes. It aggregates various storage bricks over Infiniband
+RDMA or TCP/IP interconnect into one large parallel network file system.
+GlusterFS is one of the most sophisticated file systems in terms of
+features and extensibility.  It borrows a powerful concept called
+Translators from GNU Hurd kernel. Much of the code in GlusterFS is in
+user space and easily manageable.
+
+This package contains the Python interface to the libgfapi library."""
+
+setup(
+    name='glusterfs-api',
+    version='@PACKAGE_VERSION@',
+    description='Python client library for the GlusterFS libgfapi',
+    long_description=DESC,
+    author='Gluster Community',
+    author_email='gluster-devel@nongnu.org',
+    license='LGPLv3',
+    url='http://gluster.org/',
+    package_dir={'gluster':''},
+    packages=['gluster']
+)
diff --git a/api/src/Makefile.am b/api/src/Makefile.am
index 954a71f76..7c5df3e20 100644
--- a/api/src/Makefile.am
+++ b/api/src/Makefile.am
@@ -1,9 +1,10 @@
 lib_LTLIBRARIES = libgfapi.la
 noinst_HEADERS = glfs-mem-types.h glfs-internal.h
-libgfapi_HEADERS = glfs.h
+libgfapi_HEADERS = glfs.h glfs-handles.h
 libgfapidir = $(includedir)/glusterfs/api
 
-libgfapi_la_SOURCES = glfs.c glfs-mgmt.c glfs-fops.c glfs-resolve.c
+libgfapi_la_SOURCES = glfs.c glfs-mgmt.c glfs-fops.c glfs-resolve.c \
+	glfs-handleops.c
 libgfapi_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la \
 	$(top_builddir)/rpc/rpc-lib/src/libgfrpc.la \
 	$(top_builddir)/rpc/xdr/src/libgfxdr.la \
@@ -14,13 +15,21 @@ libgfapi_la_CPPFLAGS = $(GF_CPPFLAGS) -D__USE_FILE_OFFSET64 \
 	-I$(top_srcdir)/rpc/rpc-lib/src \
 	-I$(top_srcdir)/rpc/xdr/src
 
+
 xlator_LTLIBRARIES = api.la
 xlatordir = $(libdir)/glusterfs/$(PACKAGE_VERSION)/xlator/mount
+# workaround for broken parallel install support in automake with LTLIBRARIES
+# http://debbugs.gnu.org/cgi/bugreport.cgi?bug=7328
+install_xlatorLTLIBRARIES = install-xlatorLTLIBRARIES
+$(install_xlatorLTLIBRARIES): install-libLTLIBRARIES
 
 api_la_SOURCES = glfs-master.c
-
-api_la_LDFLAGS = -module -avoidversion
-api_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la
+api_la_DEPENDENCIES = libgfapi.la
+api_la_LDFLAGS = -module -avoid-version
+api_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la \
+	$(top_builddir)/rpc/rpc-lib/src/libgfrpc.la \
+	$(top_builddir)/rpc/xdr/src/libgfxdr.la \
+	$(top_builddir)/api/src/libgfapi.la
 
 AM_CPPFLAGS = $(GF_CPPFLAGS) -I$(top_srcdir)/libglusterfs/src
 
diff --git a/api/src/glfs-fops.c b/api/src/glfs-fops.c
index c9897243e..10bb7d38b 100644
--- a/api/src/glfs-fops.c
+++ b/api/src/glfs-fops.c
@@ -13,6 +13,56 @@
 #include "glfs-mem-types.h"
 #include "syncop.h"
 #include "glfs.h"
+#include <limits.h>
+
+#ifdef NAME_MAX
+#define GF_NAME_MAX NAME_MAX
+#else
+#define GF_NAME_MAX 255
+#endif
+
+#define READDIRBUF_SIZE (sizeof(struct dirent) + GF_NAME_MAX + 1)
+
+int
+glfs_loc_link (loc_t *loc, struct iatt *iatt)
+{
+	int ret = -1;
+	inode_t *linked_inode = NULL;
+
+	if (!loc->inode) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	linked_inode = inode_link (loc->inode, loc->parent, loc->name, iatt);
+	if (linked_inode) {
+		inode_lookup (linked_inode);
+		inode_unref (linked_inode);
+		ret = 0;
+	} else {
+		ret = -1;
+		errno = ENOMEM;
+	}
+
+	return ret;
+}
+
+
+void
+glfs_iatt_to_stat (struct glfs *fs, struct iatt *iatt, struct stat *stat)
+{
+	iatt_to_stat (iatt, stat);
+	stat->st_dev = fs->dev_id;
+}
+
+
+int
+glfs_loc_unlink (loc_t *loc)
+{
+	inode_unlink (loc->inode, loc->parent, loc->name);
+
+	return 0;
+}
 
 
 struct glfs_fd *
@@ -23,6 +73,7 @@ glfs_open (struct glfs *fs, const char *path, int flags)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -33,11 +84,15 @@ glfs_open (struct glfs *fs, const char *path, int flags)
 		goto out;
 	}
 
-	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
+	glfd = glfs_fd_new (fs);
 	if (!glfd)
 		goto out;
 
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
@@ -53,6 +108,14 @@ glfs_open (struct glfs *fs, const char *path, int flags)
 		goto out;
 	}
 
+	if (glfd->fd) {
+		/* Retry. Safe to touch glfd->fd as we
+		   still have not glfs_fd_bind() yet.
+		*/
+		fd_unref (glfd->fd);
+		glfd->fd = NULL;
+	}
+
 	glfd->fd = fd_create (loc.inode, getpid());
 	if (!glfd->fd) {
 		ret = -1;
@@ -61,14 +124,22 @@ glfs_open (struct glfs *fs, const char *path, int flags)
 	}
 
 	ret = syncop_open (subvol, &loc, flags, glfd->fd);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
 	if (ret && glfd) {
 		glfs_fd_destroy (glfd);
 		glfd = NULL;
+	} else if (glfd) {
+                glfd->fd->flags = flags;
+		fd_bind (glfd->fd);
+		glfs_fd_bind (glfd);
 	}
 
+	glfs_subvol_done (fs, subvol);
+
 	return glfd;
 }
 
@@ -78,15 +149,35 @@ glfs_close (struct glfs_fd *glfd)
 {
 	xlator_t  *subvol = NULL;
 	int        ret = -1;
+	fd_t      *fd = NULL;
+	struct glfs *fs = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
+        if (!subvol) {
+                ret = -1;
+                errno = EIO;
+                goto out;
+        }
 
-	ret = syncop_flush (subvol, glfd->fd);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
 
+	ret = syncop_flush (subvol, fd);
+out:
+	fs = glfd->fs;
 	glfs_fd_destroy (glfd);
 
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -98,6 +189,7 @@ glfs_lstat (struct glfs *fs, const char *path, struct stat *stat)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -107,14 +199,18 @@ glfs_lstat (struct glfs *fs, const char *path, struct stat *stat)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (ret == 0 && stat)
-		iatt_to_stat (&iatt, stat);
+		glfs_iatt_to_stat (fs, &iatt, stat);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -126,6 +222,7 @@ glfs_stat (struct glfs *fs, const char *path, struct stat *stat)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -135,14 +232,18 @@ glfs_stat (struct glfs *fs, const char *path, struct stat *stat)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
 
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (ret == 0 && stat)
-		iatt_to_stat (&iatt, stat);
+		glfs_iatt_to_stat (fs, &iatt, stat);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -153,21 +254,34 @@ glfs_fstat (struct glfs_fd *glfd, struct stat *stat)
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
 	struct iatt      iatt = {0, };
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fstat (subvol, glfd->fd, &iatt);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fstat (subvol, fd, &iatt);
 
 	if (ret == 0 && stat)
-		iatt_to_stat (&iatt, stat);
+		glfs_iatt_to_stat (glfd->fs, &iatt, stat);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -182,6 +296,7 @@ glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
 	struct iatt      iatt = {0, };
 	uuid_t           gfid;
 	dict_t          *xattr_req = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -207,7 +322,7 @@ glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
 		goto out;
 	}
 
-	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
+	glfd = glfs_fd_new (fs);
 	if (!glfd)
 		goto out;
 
@@ -216,7 +331,11 @@ glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
 	   is a danging symlink must create the dangling
 	   destinataion.
 	*/
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret == -1 && errno != ENOENT)
 		/* Any other type of error is fatal */
 		goto out;
@@ -256,6 +375,14 @@ glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
 		}
 	}
 
+	if (glfd->fd) {
+		/* Retry. Safe to touch glfd->fd as we
+		   still have not glfs_fd_bind() yet.
+		*/
+		fd_unref (glfd->fd);
+		glfd->fd = NULL;
+	}
+
 	glfd->fd = fd_create (loc.inode, getpid());
 	if (!glfd->fd) {
 		ret = -1;
@@ -263,18 +390,34 @@ glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
 		goto out;
 	}
 
-	ret = syncop_create (subvol, &loc, flags, mode, glfd->fd, xattr_req);
+	if (ret == 0) {
+		ret = syncop_open (subvol, &loc, flags, glfd->fd);
+	} else {
+		ret = syncop_create (subvol, &loc, flags, mode, glfd->fd,
+				     xattr_req, &iatt);
+	}
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_link (&loc, &iatt);
 out:
 	loc_wipe (&loc);
 
 	if (xattr_req)
-		dict_destroy (xattr_req);
+		dict_unref (xattr_req);
 
 	if (ret && glfd) {
 		glfs_fd_destroy (glfd);
 		glfd = NULL;
+	} else if (glfd) {
+                glfd->fd->flags = flags;
+		fd_bind (glfd->fd);
+		glfs_fd_bind (glfd);
 	}
 
+	glfs_subvol_done (fs, subvol);
+
 	return glfd;
 }
 
@@ -315,33 +458,52 @@ glfs_preadv (struct glfs_fd *glfd, const struct iovec *iovec, int iovcnt,
 	     off_t offset, int flags)
 {
 	xlator_t       *subvol = NULL;
-	int             ret = -1;
-	size_t          size = -1;
+	ssize_t         ret = -1;
+	ssize_t         size = -1;
 	struct iovec   *iov = NULL;
 	int             cnt = 0;
 	struct iobref  *iobref = NULL;
+	fd_t           *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
 
 	size = iov_length (iovec, iovcnt);
 
-	ret = syncop_readv (subvol, glfd->fd, size, offset,
-			    0, &iov, &cnt, &iobref);
+	ret = syncop_readv (subvol, fd, size, offset, 0, &iov, &cnt, &iobref);
 	if (ret <= 0)
-		return ret;
+		goto out;
 
 	size = iov_copy (iovec, iovcnt, iov, cnt); /* FIXME!!! */
 
 	glfd->offset = (offset + size);
 
-	if (iov)
-		GF_FREE (iov);
-	if (iobref)
-		iobref_unref (iobref);
+	ret = size;
+out:
+        if (iov)
+                GF_FREE (iov);
+        if (iobref)
+                iobref_unref (iobref);
+
+	if (fd)
+		fd_unref (fd);
 
-	return size;
+	glfs_subvol_done (glfd->fs, subvol);
+
+	return ret;
 }
 
 
@@ -421,10 +583,6 @@ glfs_io_async_task (void *data)
 	ssize_t         ret = 0;
 
 	switch (gio->op) {
-	case GF_FOP_READ:
-		ret = glfs_preadv (gio->glfd, gio->iov, gio->count,
-				   gio->offset, gio->flags);
-		break;
 	case GF_FOP_WRITE:
 		ret = glfs_pwritev (gio->glfd, gio->iov, gio->count,
 				    gio->offset, gio->flags);
@@ -438,6 +596,12 @@ glfs_io_async_task (void *data)
 		else
 			ret = glfs_fsync (gio->glfd);
 		break;
+	case GF_FOP_DISCARD:
+		ret = glfs_discard (gio->glfd, gio->offset, gio->count);
+		break;
+        case GF_FOP_ZEROFILL:
+                ret = glfs_zerofill(gio->glfd, gio->offset, gio->count);
+                break;
 	}
 
 	return (int) ret;
@@ -445,23 +609,90 @@ glfs_io_async_task (void *data)
 
 
 int
+glfs_preadv_async_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+		       int op_ret, int op_errno, struct iovec *iovec,
+		       int count, struct iatt *stbuf, struct iobref *iobref,
+		       dict_t *xdata)
+{
+	struct glfs_io *gio = NULL;
+	xlator_t       *subvol = NULL;
+	struct glfs    *fs = NULL;
+	struct glfs_fd *glfd = NULL;
+
+
+	gio = frame->local;
+	frame->local = NULL;
+	subvol = cookie;
+	glfd = gio->glfd;
+	fs = glfd->fs;
+
+	if (op_ret <= 0)
+		goto out;
+
+	op_ret = iov_copy (gio->iov, gio->count, iovec, count);
+
+	glfd->offset = gio->offset + op_ret;
+out:
+	errno = op_errno;
+	gio->fn (gio->glfd, op_ret, gio->data);
+
+	GF_FREE (gio->iov);
+	GF_FREE (gio);
+	STACK_DESTROY (frame->root);
+	glfs_subvol_done (fs, subvol);
+
+	return 0;
+}
+
+
+int
 glfs_preadv_async (struct glfs_fd *glfd, const struct iovec *iovec, int count,
 		   off_t offset, int flags, glfs_io_cbk fn, void *data)
 {
 	struct glfs_io *gio = NULL;
 	int             ret = 0;
+	call_frame_t   *frame = NULL;
+	xlator_t       *subvol = NULL;
+	glfs_t         *fs = NULL;
+	fd_t           *fd = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	fs = glfd->fs;
+
+	frame = syncop_create_frame (THIS);
+	if (!frame) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
 
 	gio = GF_CALLOC (1, sizeof (*gio), glfs_mt_glfs_io_t);
 	if (!gio) {
+		ret = -1;
 		errno = ENOMEM;
-		return -1;
+		goto out;
 	}
 
 	gio->iov = iov_dup (iovec, count);
 	if (!gio->iov) {
-		GF_FREE (gio);
+		ret = -1;
 		errno = ENOMEM;
-		return -1;
+		goto out;
 	}
 
 	gio->op     = GF_FOP_READ;
@@ -472,15 +703,23 @@ glfs_preadv_async (struct glfs_fd *glfd, const struct iovec *iovec, int count,
 	gio->fn     = fn;
 	gio->data   = data;
 
-	ret = synctask_new (glfs_from_glfd (glfd)->ctx->env,
-			    glfs_io_async_task, glfs_io_async_cbk,
-			    NULL, gio);
+	frame->local = gio;
 
+	STACK_WIND_COOKIE (frame, glfs_preadv_async_cbk, subvol, subvol,
+			   subvol->fops->readv, fd, iov_length (iovec, count),
+			   offset, flags, NULL);
+
+out:
 	if (ret) {
 		GF_FREE (gio->iov);
 		GF_FREE (gio);
+		STACK_DESTROY (frame->root);
+		glfs_subvol_done (fs, subvol);
 	}
 
+	if (fd)
+		fd_unref (fd);
+
 	return ret;
 }
 
@@ -540,24 +779,39 @@ glfs_pwritev (struct glfs_fd *glfd, const struct iovec *iovec, int iovcnt,
 	struct iobref  *iobref = NULL;
 	struct iobuf   *iobuf = NULL;
 	struct iovec    iov = {0, };
+	fd_t           *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
 
 	size = iov_length (iovec, iovcnt);
 
 	iobuf = iobuf_get2 (subvol->ctx->iobuf_pool, size);
 	if (!iobuf) {
+		ret = -1;
 		errno = ENOMEM;
-		return -1;
+		goto out;
 	}
 
 	iobref = iobref_new ();
 	if (!iobref) {
 		iobuf_unref (iobuf);
 		errno = ENOMEM;
-		return -1;
+		ret = -1;
+		goto out;
 	}
 
 	ret = iobref_add (iobref, iobuf);
@@ -565,7 +819,8 @@ glfs_pwritev (struct glfs_fd *glfd, const struct iovec *iovec, int iovcnt,
 		iobuf_unref (iobuf);
 		iobref_unref (iobref);
 		errno = ENOMEM;
-		return -1;
+		ret = -1;
+		goto out;
 	}
 
 	iov_unload (iobuf_ptr (iobuf), iovec, iovcnt);  /* FIXME!!! */
@@ -573,17 +828,22 @@ glfs_pwritev (struct glfs_fd *glfd, const struct iovec *iovec, int iovcnt,
 	iov.iov_base = iobuf_ptr (iobuf);
 	iov.iov_len = size;
 
-	ret = syncop_writev (subvol, glfd->fd, &iov, 1, offset,
-			     iobref, flags);
+	ret = syncop_writev (subvol, fd, &iov, 1, offset, iobref, flags);
 
 	iobuf_unref (iobuf);
 	iobref_unref (iobref);
 
 	if (ret <= 0)
-		return ret;
+		goto out;
 
 	glfd->offset = (offset + size);
 
+out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -722,18 +982,31 @@ glfs_fsync (struct glfs_fd *glfd)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fsync (subvol, glfd->fd, 0);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fsync (subvol, fd, 0);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -783,18 +1056,31 @@ glfs_fdatasync (struct glfs_fd *glfd)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fsync (subvol, glfd->fd, 1);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fsync (subvol, fd, 1);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -811,18 +1097,31 @@ glfs_ftruncate (struct glfs_fd *glfd, off_t offset)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_ftruncate (subvol, glfd->fd, offset);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_ftruncate (subvol, fd, offset);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -866,6 +1165,7 @@ glfs_access (struct glfs *fs, const char *path, int mode)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -875,15 +1175,22 @@ glfs_access (struct glfs *fs, const char *path, int mode)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
 	ret = syncop_access (subvol, &loc, mode);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -897,6 +1204,7 @@ glfs_symlink (struct glfs *fs, const char *data, const char *path)
 	struct iatt      iatt = {0, };
 	uuid_t           gfid;
 	dict_t          *xattr_req = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -921,8 +1229,10 @@ glfs_symlink (struct glfs *fs, const char *data, const char *path)
 		errno = ENOMEM;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (loc.inode) {
 		errno = EEXIST;
@@ -948,12 +1258,19 @@ glfs_symlink (struct glfs *fs, const char *data, const char *path)
 		goto out;
 	}
 
-	ret = syncop_symlink (subvol, &loc, data, xattr_req);
+	ret = syncop_symlink (subvol, &loc, data, xattr_req, &iatt);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_link (&loc, &iatt);
 out:
 	loc_wipe (&loc);
 
 	if (xattr_req)
-		dict_destroy (xattr_req);
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
 
 	return ret;
 }
@@ -966,6 +1283,8 @@ glfs_readlink (struct glfs *fs, const char *path, char *buf, size_t bufsiz)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
+	char            *linkval = NULL;
 
 	__glfs_entry_fs (fs);
 
@@ -975,8 +1294,11 @@ glfs_readlink (struct glfs *fs, const char *path, char *buf, size_t bufsiz)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
@@ -986,10 +1308,18 @@ glfs_readlink (struct glfs *fs, const char *path, char *buf, size_t bufsiz)
 		goto out;
 	}
 
-	ret = syncop_readlink (subvol, &loc, &buf, bufsiz);
+	ret = syncop_readlink (subvol, &loc, &linkval, bufsiz);
+	if (ret > 0) {
+		memcpy (buf, linkval, ret);
+		GF_FREE (linkval);
+	}
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1003,6 +1333,7 @@ glfs_mknod (struct glfs *fs, const char *path, mode_t mode, dev_t dev)
 	struct iatt      iatt = {0, };
 	uuid_t           gfid;
 	dict_t          *xattr_req = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1027,8 +1358,10 @@ glfs_mknod (struct glfs *fs, const char *path, mode_t mode, dev_t dev)
 		errno = ENOMEM;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (loc.inode) {
 		errno = EEXIST;
@@ -1054,12 +1387,19 @@ glfs_mknod (struct glfs *fs, const char *path, mode_t mode, dev_t dev)
 		goto out;
 	}
 
-	ret = syncop_mknod (subvol, &loc, mode, dev, xattr_req);
+	ret = syncop_mknod (subvol, &loc, mode, dev, xattr_req, &iatt);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_link (&loc, &iatt);
 out:
 	loc_wipe (&loc);
 
 	if (xattr_req)
-		dict_destroy (xattr_req);
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
 
 	return ret;
 }
@@ -1074,6 +1414,7 @@ glfs_mkdir (struct glfs *fs, const char *path, mode_t mode)
 	struct iatt      iatt = {0, };
 	uuid_t           gfid;
 	dict_t          *xattr_req = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1098,8 +1439,10 @@ glfs_mkdir (struct glfs *fs, const char *path, mode_t mode)
 		errno = ENOMEM;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (loc.inode) {
 		errno = EEXIST;
@@ -1125,12 +1468,19 @@ glfs_mkdir (struct glfs *fs, const char *path, mode_t mode)
 		goto out;
 	}
 
-	ret = syncop_mkdir (subvol, &loc, mode, xattr_req);
+	ret = syncop_mkdir (subvol, &loc, mode, xattr_req, &iatt);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_link (&loc, &iatt);
 out:
 	loc_wipe (&loc);
 
 	if (xattr_req)
-		dict_destroy (xattr_req);
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
 
 	return ret;
 }
@@ -1143,6 +1493,7 @@ glfs_unlink (struct glfs *fs, const char *path)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1152,8 +1503,11 @@ glfs_unlink (struct glfs *fs, const char *path)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
@@ -1164,9 +1518,16 @@ glfs_unlink (struct glfs *fs, const char *path)
 	}
 
 	ret = syncop_unlink (subvol, &loc);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_unlink (&loc);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1178,6 +1539,7 @@ glfs_rmdir (struct glfs *fs, const char *path)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1187,8 +1549,11 @@ glfs_rmdir (struct glfs *fs, const char *path)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
@@ -1199,9 +1564,16 @@ glfs_rmdir (struct glfs *fs, const char *path)
 	}
 
 	ret = syncop_rmdir (subvol, &loc);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret == 0)
+		ret = glfs_loc_unlink (&loc);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1215,6 +1587,7 @@ glfs_rename (struct glfs *fs, const char *oldpath, const char *newpath)
 	loc_t            newloc = {0, };
 	struct iatt      oldiatt = {0, };
 	struct iatt      newiatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1224,31 +1597,56 @@ glfs_rename (struct glfs *fs, const char *oldpath, const char *newpath)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, oldpath, &oldloc, &oldiatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &oldloc, retry);
 
-	ret = glfs_lresolve (fs, subvol, oldpath, &oldloc, &oldiatt);
 	if (ret)
 		goto out;
+retrynew:
+	ret = glfs_lresolve (fs, subvol, newpath, &newloc, &newiatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &newloc, retrynew);
 
-	ret = glfs_lresolve (fs, subvol, newpath, &newloc, &newiatt);
 	if (ret && errno != ENOENT && newloc.parent)
 		goto out;
 
-	if ((oldiatt.ia_type == IA_IFDIR) != (newiatt.ia_type == IA_IFDIR)) {
-		/* Either both old and new must be dirs, or both must be
-		   non-dirs. Else, fail.
-		*/
-		ret = -1;
-		errno = EISDIR;
-		goto out;
-	}
+	if (newiatt.ia_type != IA_INVAL) {
+                if ((oldiatt.ia_type == IA_IFDIR) !=
+                    (newiatt.ia_type == IA_IFDIR)) {
+                       /* Either both old and new must be dirs,
+                        * or both must be non-dirs. Else, fail.
+                        */
+                       ret = -1;
+                       errno = EISDIR;
+                       goto out;
+                }
+        }
 
 	/* TODO: check if new or old is a prefix of the other, and fail EINVAL */
 
 	ret = syncop_rename (subvol, &oldloc, &newloc);
+
+	if (ret == -1 && errno == ESTALE) {
+		if (reval < DEFAULT_REVAL_COUNT) {
+			reval++;
+			loc_wipe (&oldloc);
+			loc_wipe (&newloc);
+			goto retry;
+		}
+	}
+
+	if (ret == 0)
+		inode_rename (oldloc.parent->table, oldloc.parent, oldloc.name,
+			      newloc.parent, newloc.name, oldloc.inode,
+			      &oldiatt);
 out:
 	loc_wipe (&oldloc);
 	loc_wipe (&newloc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1262,6 +1660,7 @@ glfs_link (struct glfs *fs, const char *oldpath, const char *newpath)
 	loc_t            newloc = {0, };
 	struct iatt      oldiatt = {0, };
 	struct iatt      newiatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1271,12 +1670,18 @@ glfs_link (struct glfs *fs, const char *oldpath, const char *newpath)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_lresolve (fs, subvol, oldpath, &oldloc, &oldiatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &oldloc, retry);
 
-	ret = glfs_lresolve (fs, subvol, oldpath, &oldloc, &oldiatt);
 	if (ret)
 		goto out;
+retrynew:
+	ret = glfs_lresolve (fs, subvol, newpath, &newloc, &newiatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &newloc, retrynew);
 
-	ret = glfs_lresolve (fs, subvol, newpath, &newloc, &newiatt);
 	if (ret == 0) {
 		ret = -1;
 		errno = EEXIST;
@@ -1289,11 +1694,32 @@ glfs_link (struct glfs *fs, const char *oldpath, const char *newpath)
 		goto out;
 	}
 
+        /* Filling the inode of the hard link to be same as that of the
+           original file
+        */
+	if (newloc.inode) {
+		inode_unref (newloc.inode);
+		newloc.inode = NULL;
+	}
+        newloc.inode = inode_ref (oldloc.inode);
+
 	ret = syncop_link (subvol, &oldloc, &newloc);
+
+	if (ret == -1 && errno == ESTALE) {
+		loc_wipe (&oldloc);
+		loc_wipe (&newloc);
+		if (reval--)
+			goto retry;
+	}
+
+	if (ret == 0)
+		ret = glfs_loc_link (&newloc, &oldiatt);
 out:
 	loc_wipe (&oldloc);
 	loc_wipe (&newloc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1306,6 +1732,7 @@ glfs_opendir (struct glfs *fs, const char *path)
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1316,12 +1743,16 @@ glfs_opendir (struct glfs *fs, const char *path)
 		goto out;
 	}
 
-	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
+	glfd = glfs_fd_new (fs);
 	if (!glfd)
 		goto out;
+
 	INIT_LIST_HEAD (&glfd->entries);
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
@@ -1331,6 +1762,14 @@ glfs_opendir (struct glfs *fs, const char *path)
 		goto out;
 	}
 
+	if (glfd->fd) {
+		/* Retry. Safe to touch glfd->fd as we
+		   still have not glfs_fd_bind() yet.
+		*/
+		fd_unref (glfd->fd);
+		glfd->fd = NULL;
+	}
+
 	glfd->fd = fd_create (loc.inode, getpid());
 	if (!glfd->fd) {
 		ret = -1;
@@ -1339,14 +1778,21 @@ glfs_opendir (struct glfs *fs, const char *path)
 	}
 
 	ret = syncop_opendir (subvol, &loc, glfd->fd);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
 	if (ret && glfd) {
 		glfs_fd_destroy (glfd);
 		glfd = NULL;
+	} else {
+		fd_bind (glfd->fd);
+		glfs_fd_bind (glfd);
 	}
 
+	glfs_subvol_done (fs, subvol);
+
 	return glfd;
 }
 
@@ -1398,6 +1844,70 @@ glfs_seekdir (struct glfs_fd *fd, long offset)
 	*/
 }
 
+int
+glfs_discard_async (struct glfs_fd *glfd, off_t offset, size_t len,
+		      glfs_io_cbk fn, void *data)
+{
+	struct glfs_io *gio = NULL;
+	int             ret = 0;
+
+	gio = GF_CALLOC (1, sizeof (*gio), glfs_mt_glfs_io_t);
+	if (!gio) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	gio->op     = GF_FOP_DISCARD;
+	gio->glfd   = glfd;
+	gio->offset = offset;
+	gio->count  = len;
+	gio->fn     = fn;
+	gio->data   = data;
+
+	ret = synctask_new (glfs_from_glfd (glfd)->ctx->env,
+			    glfs_io_async_task, glfs_io_async_cbk,
+			    NULL, gio);
+
+	if (ret) {
+		GF_FREE (gio->iov);
+		GF_FREE (gio);
+	}
+
+	return ret;
+}
+
+int
+glfs_zerofill_async (struct glfs_fd *glfd, off_t offset, size_t len,
+                      glfs_io_cbk fn, void *data)
+{
+        struct glfs_io *gio  = NULL;
+        int             ret  = 0;
+
+        gio = GF_CALLOC (1, sizeof (*gio), glfs_mt_glfs_io_t);
+        if (!gio) {
+                errno = ENOMEM;
+                return -1;
+        }
+
+        gio->op     = GF_FOP_ZEROFILL;
+        gio->glfd   = glfd;
+        gio->offset = offset;
+        gio->count  = len;
+        gio->fn     = fn;
+        gio->data   = data;
+
+        ret = synctask_new (glfs_from_glfd (glfd)->ctx->env,
+                            glfs_io_async_task, glfs_io_async_cbk,
+                            NULL, gio);
+
+        if (ret) {
+                GF_FREE (gio->iov);
+                GF_FREE (gio);
+        }
+
+        return ret;
+}
+
 
 void
 gf_dirent_to_dirent (gf_dirent_t *gf_dirent, struct dirent *dirent)
@@ -1416,54 +1926,81 @@ gf_dirent_to_dirent (gf_dirent_t *gf_dirent, struct dirent *dirent)
 	dirent->d_namlen = strlen (gf_dirent->d_name);
 #endif
 
-	strncpy (dirent->d_name, gf_dirent->d_name, 256);
+	strncpy (dirent->d_name, gf_dirent->d_name, GF_NAME_MAX + 1);
 }
 
 
 int
-glfd_entry_refresh (struct glfs_fd *glfd)
+glfd_entry_refresh (struct glfs_fd *glfd, int plus)
 {
 	xlator_t        *subvol = NULL;
 	gf_dirent_t      entries;
 	gf_dirent_t      old;
 	int              ret = -1;
+	fd_t            *fd = NULL;
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
+		ret = -1;
 		errno = EIO;
-		return -1;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	if (fd->inode->ia_type != IA_IFDIR) {
+		ret = -1;
+		errno = EBADF;
+		goto out;
 	}
 
 	INIT_LIST_HEAD (&entries.list);
 	INIT_LIST_HEAD (&old.list);
 
-	ret = syncop_readdir (subvol, glfd->fd, 131072, glfd->offset,
-			      &entries);
+	if (plus)
+		ret = syncop_readdirp (subvol, fd, 131072, glfd->offset,
+				       NULL, &entries);
+	else
+		ret = syncop_readdir (subvol, fd, 131072, glfd->offset,
+				      &entries);
 	if (ret >= 0) {
-		/* spurious errno is dangerous for glfd_entry_next() */
-		errno = 0;
+		if (plus)
+			gf_link_inodes_from_dirent (THIS, fd->inode, &entries);
 
 		list_splice_init (&glfd->entries, &old.list);
 		list_splice_init (&entries.list, &glfd->entries);
+
+		/* spurious errno is dangerous for glfd_entry_next() */
+		errno = 0;
 	}
 
 	if (ret > 0)
 		glfd->next = list_entry (glfd->entries.next, gf_dirent_t, list);
 
 	gf_dirent_free (&old);
+out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
 
 	return ret;
 }
 
 
 gf_dirent_t *
-glfd_entry_next (struct glfs_fd *glfd)
+glfd_entry_next (struct glfs_fd *glfd, int plus)
 {
 	gf_dirent_t     *entry = NULL;
 	int              ret = -1;
 
 	if (!glfd->offset || !glfd->next) {
-		ret = glfd_entry_refresh (glfd);
+		ret = glfd_entry_refresh (glfd, plus);
 		if (ret < 0)
 			return NULL;
 	}
@@ -1483,22 +2020,57 @@ glfd_entry_next (struct glfs_fd *glfd)
 }
 
 
+static struct dirent *
+glfs_readdirbuf_get (struct glfs_fd *glfd)
+{
+        struct dirent *buf = NULL;
+
+        LOCK (&glfd->fd->lock);
+        {
+                buf = glfd->readdirbuf;
+                if (buf) {
+                        memset (buf, 0, READDIRBUF_SIZE);
+                        goto unlock;
+                }
+
+                buf = GF_CALLOC (1, READDIRBUF_SIZE, glfs_mt_readdirbuf_t);
+                if (!buf) {
+                        errno = ENOMEM;
+                        goto unlock;
+                }
+
+                glfd->readdirbuf = buf;
+        }
+unlock:
+        UNLOCK (&glfd->fd->lock);
+
+        return buf;
+}
+
+
 int
-glfs_readdir_r (struct glfs_fd *glfd, struct dirent *buf, struct dirent **res)
+glfs_readdirplus_r (struct glfs_fd *glfd, struct stat *stat, struct dirent *ext,
+		    struct dirent **res)
 {
 	int              ret = 0;
 	gf_dirent_t     *entry = NULL;
+	struct dirent   *buf = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	if (glfd->fd->inode->ia_type != IA_IFDIR) {
-		ret = -1;
-		errno = EBADF;
-		goto out;
+	errno = 0;
+
+	if (ext)
+		buf = ext;
+	else
+		buf = glfs_readdirbuf_get (glfd);
+
+	if (!buf) {
+		errno = ENOMEM;
+		return -1;
 	}
 
-	errno = 0;
-	entry = glfd_entry_next (glfd);
+	entry = glfd_entry_next (glfd, !!stat);
 	if (errno)
 		ret = -1;
 
@@ -1509,20 +2081,53 @@ glfs_readdir_r (struct glfs_fd *glfd, struct dirent *buf, struct dirent **res)
 			*res = NULL;
 	}
 
-	if (entry)
+	if (entry) {
 		gf_dirent_to_dirent (entry, buf);
-out:
+		if (stat)
+			glfs_iatt_to_stat (glfd->fs, &entry->d_stat, stat);
+	}
+
 	return ret;
 }
 
 
 int
+glfs_readdir_r (struct glfs_fd *glfd, struct dirent *buf, struct dirent **res)
+{
+	return glfs_readdirplus_r (glfd, 0, buf, res);
+}
+
+
+struct dirent *
+glfs_readdirplus (struct glfs_fd *glfd, struct stat *stat)
+{
+        struct dirent *res = NULL;
+        int ret = -1;
+
+        ret = glfs_readdirplus_r (glfd, stat, NULL, &res);
+        if (ret)
+                return NULL;
+
+        return res;
+}
+
+
+
+struct dirent *
+glfs_readdir (struct glfs_fd *glfd)
+{
+        return glfs_readdirplus (glfd, NULL);
+}
+
+
+int
 glfs_statvfs (struct glfs *fs, const char *path, struct statvfs *buf)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1532,15 +2137,22 @@ glfs_statvfs (struct glfs *fs, const char *path, struct statvfs *buf)
 		errno = EIO;
 		goto out;
 	}
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
-	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
 	if (ret)
 		goto out;
 
 	ret = syncop_statfs (subvol, &loc, buf);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1553,6 +2165,7 @@ glfs_setattr (struct glfs *fs, const char *path, struct iatt *iatt,
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      riatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1562,19 +2175,25 @@ glfs_setattr (struct glfs *fs, const char *path, struct iatt *iatt,
 		errno = EIO;
 		goto out;
 	}
-
+retry:
 	if (follow)
-		ret = glfs_resolve (fs, subvol, path, &loc, &riatt);
+		ret = glfs_resolve (fs, subvol, path, &loc, &riatt, reval);
 	else
-		ret = glfs_lresolve (fs, subvol, path, &loc, &riatt);
+		ret = glfs_lresolve (fs, subvol, path, &loc, &riatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 
 	if (ret)
 		goto out;
 
 	ret = syncop_setattr (subvol, &loc, iatt, valid, 0, 0);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1584,18 +2203,31 @@ glfs_fsetattr (struct glfs_fd *glfd, struct iatt *iatt, int valid)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fsetattr (subvol, glfd->fd, iatt, valid, 0, 0);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fsetattr (subvol, fd, iatt, valid, 0, 0);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -1784,6 +2416,7 @@ glfs_getxattr_common (struct glfs *fs, const char *path, const char *name,
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
 	dict_t          *xattr = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1793,15 +2426,21 @@ glfs_getxattr_common (struct glfs *fs, const char *path, const char *name,
 		errno = EIO;
 		goto out;
 	}
-
+retry:
 	if (follow)
-		ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
 	else
-		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
 	ret = syncop_getxattr (subvol, &loc, &xattr, name);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
@@ -1809,6 +2448,8 @@ glfs_getxattr_common (struct glfs *fs, const char *path, const char *name,
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1836,52 +2477,45 @@ glfs_fgetxattr (struct glfs_fd *glfd, const char *name, void *value,
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
 	dict_t          *xattr = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fgetxattr (subvol, glfd->fd, &xattr, name);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fgetxattr (subvol, fd, &xattr, name);
 	if (ret)
 		goto out;
 
 	ret = glfs_getxattr_process (value, size, xattr, name);
 out:
-	return ret;
-}
-
-
-static int
-dict_keys_join (void *value, int size, dict_t *dict)
-{
-	int len = 0;
-
-	int add_key_len (dict_t *d, char *k, data_t *v, void *o)
-	{
-		if (value && size > len)
-			strncpy (value + len, k, size - len);
-
-		len += (strlen (k) + 1);
-
-		return 0;
-	}
+	if (fd)
+		fd_unref (fd);
 
-	dict_foreach (dict, add_key_len, 0);
+	glfs_subvol_done (glfd->fs, subvol);
 
-	return len;
+	return ret;
 }
 
+
 int
 glfs_listxattr_process (void *value, size_t size, dict_t *xattr)
 {
 	int     ret = -1;
 
-	ret = dict_keys_join (NULL, 0, xattr);
+	ret = dict_keys_join (NULL, 0, xattr, NULL);
 
 	if (!value || !size)
 		goto out;
@@ -1892,7 +2526,7 @@ glfs_listxattr_process (void *value, size_t size, dict_t *xattr)
 		goto out;
 	}
 
-	dict_keys_join (value, size, xattr);
+	dict_keys_join (value, size, xattr, NULL);
 out:
 	if (xattr)
 		dict_unref (xattr);
@@ -1909,6 +2543,7 @@ glfs_listxattr_common (struct glfs *fs, const char *path, void *value,
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
 	dict_t          *xattr = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -1919,14 +2554,21 @@ glfs_listxattr_common (struct glfs *fs, const char *path, void *value,
 		goto out;
 	}
 
+retry:
 	if (follow)
-		ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
 	else
-		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
 	ret = syncop_getxattr (subvol, &loc, &xattr, NULL);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
@@ -1934,6 +2576,8 @@ glfs_listxattr_common (struct glfs *fs, const char *path, void *value,
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -1958,22 +2602,35 @@ glfs_flistxattr (struct glfs_fd *glfd, void *value, size_t size)
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
 	dict_t          *xattr = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fgetxattr (subvol, glfd->fd, &xattr, NULL);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fgetxattr (subvol, fd, &xattr, NULL);
 	if (ret)
 		goto out;
 
 	ret = glfs_listxattr_process (value, size, xattr);
 out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -2007,6 +2664,7 @@ glfs_setxattr_common (struct glfs *fs, const char *path, const char *name,
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
 	dict_t          *xattr = NULL;
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -2016,11 +2674,14 @@ glfs_setxattr_common (struct glfs *fs, const char *path, const char *name,
 		errno = EIO;
 		goto out;
 	}
-
+retry:
 	if (follow)
-		ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
 	else
-		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
@@ -2032,11 +2693,16 @@ glfs_setxattr_common (struct glfs *fs, const char *path, const char *name,
 	}
 
 	ret = syncop_setxattr (subvol, &loc, xattr, flags);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 out:
 	loc_wipe (&loc);
 	if (xattr)
 		dict_unref (xattr);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -2064,16 +2730,24 @@ glfs_fsetxattr (struct glfs_fd *glfd, const char *name, const void *value,
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
 	dict_t          *xattr = NULL;
+	fd_t            *fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
 	xattr = dict_for_key_value (name, value, size);
 	if (!xattr) {
 		ret = -1;
@@ -2081,11 +2755,16 @@ glfs_fsetxattr (struct glfs_fd *glfd, const char *name, const void *value,
 		goto out;
 	}
 
-	ret = syncop_fsetxattr (subvol, glfd->fd, xattr, flags);
+	ret = syncop_fsetxattr (subvol, fd, xattr, flags);
 out:
 	if (xattr)
 		dict_unref (xattr);
 
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
 
@@ -2098,6 +2777,7 @@ glfs_removexattr_common (struct glfs *fs, const char *path, const char *name,
 	xlator_t        *subvol = NULL;
 	loc_t            loc = {0, };
 	struct iatt      iatt = {0, };
+	int              reval = 0;
 
 	__glfs_entry_fs (fs);
 
@@ -2107,18 +2787,26 @@ glfs_removexattr_common (struct glfs *fs, const char *path, const char *name,
 		errno = EIO;
 		goto out;
 	}
-
+retry:
 	if (follow)
-		ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
 	else
-		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt);
+		ret = glfs_lresolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 	if (ret)
 		goto out;
 
 	ret = syncop_removexattr (subvol, &loc, name);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
 out:
 	loc_wipe (&loc);
 
+	glfs_subvol_done (fs, subvol);
+
 	return ret;
 }
 
@@ -2142,17 +2830,423 @@ glfs_fremovexattr (struct glfs_fd *glfd, const char *name)
 {
 	int              ret = -1;
 	xlator_t        *subvol = NULL;
+	fd_t            *fd = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fremovexattr (subvol, fd, name);
+out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
+	return ret;
+}
+
+
+int
+glfs_fallocate (struct glfs_fd *glfd, int keep_size, off_t offset, size_t len)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	fd_t		*fd = NULL;
 
 	__glfs_entry_fd (glfd);
 
-	subvol = glfs_fd_subvol (glfd);
+	subvol = glfs_active_subvol (glfd->fs);
 	if (!subvol) {
 		ret = -1;
 		errno = EIO;
 		goto out;
 	}
 
-	ret = syncop_fremovexattr (subvol, glfd->fd, name);
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_fallocate (subvol, fd, keep_size, offset, len);
 out:
+	if (fd)
+		fd_unref(fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
 	return ret;
 }
+
+
+int
+glfs_discard (struct glfs_fd *glfd, off_t offset, size_t len)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	fd_t		*fd = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	ret = syncop_discard (subvol, fd, offset, len);
+out:
+	if (fd)
+		fd_unref(fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
+	return ret;
+}
+
+int
+glfs_zerofill (struct glfs_fd *glfd, off_t offset, size_t len)
+{
+        int               ret             = -1;
+        xlator_t         *subvol          = NULL;
+        fd_t             *fd              = NULL;
+
+        __glfs_entry_fd (glfd);
+
+        subvol = glfs_active_subvol (glfd->fs);
+        if (!subvol) {
+                errno = EIO;
+                goto out;
+        }
+
+        fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+        if (!fd) {
+                errno = EBADFD;
+                goto out;
+        }
+
+        ret = syncop_zerofill (subvol, fd, offset, len);
+out:
+        if (fd)
+                fd_unref(fd);
+
+        glfs_subvol_done (glfd->fs, subvol);
+
+        return ret;
+}
+
+int
+glfs_chdir (struct glfs *fs, const char *path)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+	int              reval = 0;
+
+	__glfs_entry_fs (fs);
+
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret)
+		goto out;
+
+	if (!IA_ISDIR (iatt.ia_type)) {
+		ret = -1;
+		errno = ENOTDIR;
+		goto out;
+	}
+
+	glfs_cwd_set (fs, loc.inode);
+
+out:
+	loc_wipe (&loc);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+
+int
+glfs_fchdir (struct glfs_fd *glfd)
+{
+	int       ret = -1;
+	inode_t  *inode = NULL;
+	xlator_t *subvol = NULL;
+	fd_t     *fd = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	inode = fd->inode;
+
+	if (!IA_ISDIR (inode->ia_type)) {
+		ret = -1;
+		errno = ENOTDIR;
+		goto out;
+	}
+
+	glfs_cwd_set (glfd->fs, inode);
+	ret = 0;
+out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
+	return ret;
+}
+
+
+char *
+glfs_realpath (struct glfs *fs, const char *path, char *resolved_path)
+{
+	int              ret = -1;
+	char            *retpath = NULL;
+	char            *allocpath = NULL;
+	xlator_t        *subvol = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+	int              reval = 0;
+
+	__glfs_entry_fs (fs);
+
+	if (resolved_path)
+		retpath = resolved_path;
+	else
+		retpath = allocpath = malloc (PATH_MAX + 1);
+
+	if (!retpath) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+retry:
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt, reval);
+
+	ESTALE_RETRY (ret, errno, reval, &loc, retry);
+
+	if (ret)
+		goto out;
+
+	if (loc.path) {
+		strncpy (retpath, loc.path, PATH_MAX);
+		retpath[PATH_MAX] = 0;
+	}
+
+out:
+	loc_wipe (&loc);
+
+	if (ret == -1) {
+		if (allocpath)
+			free (allocpath);
+		retpath = NULL;
+	}
+
+	glfs_subvol_done (fs, subvol);
+
+	return retpath;
+}
+
+
+char *
+glfs_getcwd (struct glfs *fs, char *buf, size_t n)
+{
+	int              ret = -1;
+	inode_t         *inode = NULL;
+	char            *path = NULL;
+
+	__glfs_entry_fs (fs);
+
+	if (!buf || n < 2) {
+		ret = -1;
+		errno = EINVAL;
+		goto out;
+	}
+
+	inode = glfs_cwd_get (fs);
+
+	if (!inode) {
+		strncpy (buf, "/", n);
+		ret = 0;
+		goto out;
+	}
+
+	ret = inode_path (inode, 0, &path);
+	if (n <= ret) {
+		ret = -1;
+		errno = ERANGE;
+		goto out;
+	}
+
+	strncpy (buf, path, n);
+	ret = 0;
+out:
+	GF_FREE (path);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (ret < 0)
+		return NULL;
+
+	return buf;
+}
+
+
+static void
+gf_flock_to_flock (struct gf_flock *gf_flock, struct flock *flock)
+{
+	flock->l_type   = gf_flock->l_type;
+	flock->l_whence = gf_flock->l_whence;
+	flock->l_start  = gf_flock->l_start;
+	flock->l_len    = gf_flock->l_len;
+	flock->l_pid    = gf_flock->l_pid;
+}
+
+
+static void
+gf_flock_from_flock (struct gf_flock *gf_flock, struct flock *flock)
+{
+	gf_flock->l_type   = flock->l_type;
+	gf_flock->l_whence = flock->l_whence;
+	gf_flock->l_start  = flock->l_start;
+	gf_flock->l_len    = flock->l_len;
+	gf_flock->l_pid    = flock->l_pid;
+}
+
+
+int
+glfs_posix_lock (struct glfs_fd *glfd, int cmd, struct flock *flock)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	struct gf_flock  gf_flock = {0, };
+	struct gf_flock  saved_flock = {0, };
+	fd_t            *fd = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_active_subvol (glfd->fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (glfd->fs, subvol, glfd);
+	if (!fd) {
+		ret = -1;
+		errno = EBADFD;
+		goto out;
+	}
+
+	gf_flock_from_flock (&gf_flock, flock);
+	gf_flock_from_flock (&saved_flock, flock);
+	ret = syncop_lk (subvol, fd, cmd, &gf_flock);
+	gf_flock_to_flock (&gf_flock, flock);
+
+	if (ret == 0 && (cmd == F_SETLK || cmd == F_SETLKW))
+		fd_lk_insert_and_merge (fd, cmd, &saved_flock);
+out:
+	if (fd)
+		fd_unref (fd);
+
+	glfs_subvol_done (glfd->fs, subvol);
+
+	return ret;
+}
+
+
+struct glfs_fd *
+glfs_dup (struct glfs_fd *glfd)
+{
+	xlator_t  *subvol = NULL;
+	fd_t      *fd = NULL;
+	glfs_fd_t *dupfd = NULL;
+	struct glfs *fs = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	fs = glfd->fs;
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		errno = EIO;
+		goto out;
+	}
+
+	fd = glfs_resolve_fd (fs, subvol, glfd);
+	if (!fd) {
+		errno = EBADFD;
+		goto out;
+	}
+
+	dupfd = glfs_fd_new (fs);
+	if (!dupfd) {
+		errno = ENOMEM;
+		goto out;
+	}
+
+	dupfd->fd = fd_ref (fd);
+out:
+	if (fd)
+		fd_unref (fd);
+	if (dupfd)
+		glfs_fd_bind (dupfd);
+
+	glfs_subvol_done (fs, subvol);
+
+	return dupfd;
+}
diff --git a/api/src/glfs-handleops.c b/api/src/glfs-handleops.c
new file mode 100644
index 000000000..9c707a619
--- /dev/null
+++ b/api/src/glfs-handleops.c
@@ -0,0 +1,1278 @@
+/*
+ *  Copyright (c) 2013 Red Hat, Inc. <http://www.redhat.com>
+ *  This file is part of GlusterFS.
+ *
+ *  This file is licensed to you under your choice of the GNU Lesser
+ *  General Public License, version 3 or any later version (LGPLv3 or
+ *  later), or the GNU General Public License, version 2 (GPLv2), in all
+ *  cases as published by the Free Software Foundation.
+ */
+
+
+#include "glfs-internal.h"
+#include "glfs-mem-types.h"
+#include "syncop.h"
+#include "glfs.h"
+#include "glfs-handles.h"
+
+static void
+glfs_iatt_from_stat (struct stat *stat, int valid, struct iatt *iatt,
+		     int *glvalid)
+{
+	/* validate in args */
+	if ((stat == NULL) || (iatt == NULL) || (glvalid == NULL)) {
+		errno = EINVAL;
+		return;
+	}
+
+	*glvalid = 0;
+
+	if (valid & GFAPI_SET_ATTR_MODE) {
+		iatt->ia_prot = ia_prot_from_st_mode (stat->st_mode);
+		*glvalid |= GF_SET_ATTR_MODE;
+	}
+
+	if (valid & GFAPI_SET_ATTR_UID) {
+		iatt->ia_uid = stat->st_uid;
+		*glvalid |= GF_SET_ATTR_UID;
+	}
+
+	if (valid & GFAPI_SET_ATTR_GID) {
+		iatt->ia_gid = stat->st_gid;
+		*glvalid |= GF_SET_ATTR_GID;
+	}
+
+	if (valid & GFAPI_SET_ATTR_ATIME) {
+		iatt->ia_atime = stat->st_atime;
+		iatt->ia_atime_nsec = ST_ATIM_NSEC (stat);
+		*glvalid |= GF_SET_ATTR_ATIME;
+	}
+
+	if (valid & GFAPI_SET_ATTR_MTIME) {
+		iatt->ia_mtime = stat->st_mtime;
+		iatt->ia_mtime_nsec = ST_MTIM_NSEC (stat);
+		*glvalid |= GF_SET_ATTR_MTIME;
+	}
+
+	return;
+}
+
+struct glfs_object *
+glfs_h_lookupat (struct glfs *fs, struct glfs_object *parent,
+		 const char *path, struct stat *stat)
+{
+	int                      ret = 0;
+	xlator_t                *subvol = NULL;
+	inode_t                 *inode = NULL;
+	struct iatt              iatt = {0, };
+	struct glfs_object      *object = NULL;
+	loc_t                    loc = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (path == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	if (parent) {
+		inode = glfs_resolve_inode (fs, subvol, parent);
+		if (!inode) {
+			errno = ESTALE;
+			goto out;
+		}
+	}
+
+	/* fop/op */
+	ret = glfs_resolve_at (fs, subvol, inode, path, &loc, &iatt,
+			       0 /*TODO: links? */, 0);
+
+	/* populate out args */
+	if (!ret) {
+		if (stat)
+			glfs_iatt_to_stat (fs, &iatt, stat);
+
+		ret = glfs_create_object (&loc, &object);
+	}
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+int
+glfs_h_stat (struct glfs *fs, struct glfs_object *object, struct stat *stat)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	inode_t         *inode = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	/* populate loc */
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_stat (subvol, &loc, &iatt);
+
+	/* populate out args */
+	if (!ret && stat) {
+		glfs_iatt_to_stat (fs, &iatt, stat);
+	}
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+int
+glfs_h_getattrs (struct glfs *fs, struct glfs_object *object, struct stat *stat)
+{
+	int                      ret = 0;
+	xlator_t                *subvol = NULL;
+	inode_t                 *inode = NULL;
+	struct iatt              iatt = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	/* fop/op */
+	ret = glfs_resolve_base (fs, subvol, inode, &iatt);
+
+	/* populate out args */
+	if (!ret && stat) {
+		glfs_iatt_to_stat (fs, &iatt, stat);
+	}
+
+out:
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+int
+glfs_h_setattrs (struct glfs *fs, struct glfs_object *object, struct stat *stat,
+		 int valid)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	inode_t         *inode = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+	int              glvalid = 0;
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL) || (stat == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	/* map valid masks from in args */
+	glfs_iatt_from_stat (stat, valid, &iatt, &glvalid);
+
+	/* populate loc */
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_setattr (subvol, &loc, &iatt, glvalid, 0, 0);
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+struct glfs_fd *
+glfs_h_open (struct glfs *fs, struct glfs_object *object, int flags)
+{
+	int              ret = -1;
+	struct glfs_fd  *glfd = NULL;
+	xlator_t        *subvol = NULL;
+	inode_t         *inode = NULL;
+	loc_t            loc = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	/* check types to open */
+	if (IA_ISDIR (inode->ia_type)) {
+		ret = -1;
+		errno = EISDIR;
+		goto out;
+	}
+
+	if (!IA_ISREG (inode->ia_type)) {
+		ret = -1;
+		errno = EINVAL;
+		goto out;
+	}
+
+	glfd = glfs_fd_new (fs);
+	if (!glfd) {
+		errno = ENOMEM;
+		goto out;
+	}
+
+	glfd->fd = fd_create (inode, getpid());
+	if (!glfd->fd) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	/* populate loc */
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_open (subvol, &loc, flags, glfd->fd);
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (ret && glfd) {
+		glfs_fd_destroy (glfd);
+		glfd = NULL;
+	} else {
+		glfd->fd->flags = flags;
+		fd_bind (glfd->fd);
+		glfs_fd_bind (glfd);
+	}
+
+	glfs_subvol_done (fs, subvol);
+
+	return glfd;
+}
+
+struct glfs_object *
+glfs_h_creat (struct glfs *fs, struct glfs_object *parent, const char *path,
+	      int flags, mode_t mode, struct stat *stat)
+{
+	int                 ret = -1;
+	struct glfs_fd     *glfd = NULL;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	loc_t               loc = {0, };
+	struct iatt         iatt = {0, };
+	uuid_t              gfid;
+	dict_t             *xattr_req = NULL;
+	struct glfs_object *object = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (parent == NULL) || (path == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, parent);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	xattr_req = dict_new ();
+	if (!xattr_req) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	uuid_generate (gfid);
+	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+	if (ret) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_PINODE (inode, loc, ret, errno, out, path);
+
+	glfd = glfs_fd_new (fs);
+	if (!glfd)
+		goto out;
+
+	glfd->fd = fd_create (loc.inode, getpid());
+	if (!glfd->fd) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	/* fop/op */
+	ret = syncop_create (subvol, &loc, flags, mode, glfd->fd,
+			     xattr_req, &iatt);
+
+	/* populate out args */
+	if (ret == 0) {
+		/* TODO: If the inode existed in the cache (say file already
+		   exists), then the glfs_loc_link will not update the
+		   loc.inode, as a result we will have a 0000 GFID that we
+		   would copy out to the object, this needs to be fixed.
+		*/
+		ret = glfs_loc_link (&loc, &iatt);
+		if (ret != 0) {
+			goto out;
+		}
+
+		if (stat)
+			glfs_iatt_to_stat (fs, &iatt, stat);
+
+		ret = glfs_create_object (&loc, &object);
+	}
+
+out:
+	if (ret && object != NULL) {
+		glfs_h_close (object);
+		object = NULL;
+	}
+
+	loc_wipe(&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (xattr_req)
+		dict_unref (xattr_req);
+
+	if (glfd) {
+		glfs_fd_destroy (glfd);
+		glfd = NULL;
+	}
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+struct glfs_object *
+glfs_h_mkdir (struct glfs *fs, struct glfs_object *parent, const char *path,
+	      mode_t mode, struct stat *stat)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	loc_t               loc = {0, };
+	struct iatt         iatt = {0, };
+	uuid_t              gfid;
+	dict_t             *xattr_req = NULL;
+	struct glfs_object *object = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (parent == NULL) || (path == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, parent);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	xattr_req = dict_new ();
+	if (!xattr_req) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	uuid_generate (gfid);
+	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+	if (ret) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_PINODE (inode, loc, ret, errno, out, path);
+
+	/* fop/op */
+	ret = syncop_mkdir (subvol, &loc, mode, xattr_req, &iatt);
+
+	/* populate out args */
+	if ( ret == 0 )  {
+		ret = glfs_loc_link (&loc, &iatt);
+		if (ret != 0) {
+			goto out;
+		}
+
+		if (stat)
+			glfs_iatt_to_stat (fs, &iatt, stat);
+
+		ret = glfs_create_object (&loc, &object);
+	}
+
+out:
+	if (ret && object != NULL) {
+		glfs_h_close (object);
+		object = NULL;
+	}
+
+	loc_wipe(&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (xattr_req)
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+struct glfs_object *
+glfs_h_mknod (struct glfs *fs, struct glfs_object *parent, const char *path,
+	      mode_t mode, dev_t dev, struct stat *stat)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	loc_t               loc = {0, };
+	struct iatt         iatt = {0, };
+	uuid_t              gfid;
+	dict_t             *xattr_req = NULL;
+	struct glfs_object *object = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (parent == NULL) || (path == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, parent);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	xattr_req = dict_new ();
+	if (!xattr_req) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	uuid_generate (gfid);
+	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+	if (ret) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_PINODE (inode, loc, ret, errno, out, path);
+
+	/* fop/op */
+	ret = syncop_mknod (subvol, &loc, mode, dev, xattr_req, &iatt);
+
+	/* populate out args */
+	if (ret == 0) {
+		ret = glfs_loc_link (&loc, &iatt);
+		if (ret != 0) {
+			goto out;
+		}
+
+		if (stat)
+			glfs_iatt_to_stat (fs, &iatt, stat);
+
+		ret = glfs_create_object (&loc, &object);
+	}
+out:
+	if (ret && object != NULL) {
+		glfs_h_close (object);
+		object = NULL;
+	}
+
+	loc_wipe(&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (xattr_req)
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+int
+glfs_h_unlink (struct glfs *fs, struct glfs_object *parent, const char *path)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	loc_t               loc = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (parent == NULL) || (path == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if ( !subvol ) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, parent);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	ret = glfs_resolve_at (fs, subvol, inode, path, &loc, NULL, 0 , 0);
+	if (ret != 0) {
+		goto out;
+	}
+
+	if (!IA_ISDIR(loc.inode->ia_type)) {
+		ret = syncop_unlink (subvol, &loc);
+		if (ret != 0) {
+			goto out;
+		}
+	} else {
+		ret = syncop_rmdir (subvol, &loc);
+		if (ret != 0) {
+			goto out;
+		}
+	}
+
+	if (ret == 0)
+		ret = glfs_loc_unlink (&loc);
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+struct glfs_fd *
+glfs_h_opendir (struct glfs *fs, struct glfs_object *object)
+{
+	int              ret = -1;
+	struct glfs_fd  *glfd = NULL;
+	xlator_t        *subvol = NULL;
+	inode_t         *inode = NULL;
+	loc_t            loc = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	if (!IA_ISDIR (inode->ia_type)) {
+		ret = -1;
+		errno = ENOTDIR;
+		goto out;
+	}
+
+	glfd = glfs_fd_new (fs);
+	if (!glfd)
+		goto out;
+
+	INIT_LIST_HEAD (&glfd->entries);
+
+	glfd->fd = fd_create (inode, getpid());
+	if (!glfd->fd) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_opendir (subvol, &loc, glfd->fd);
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (ret && glfd) {
+		glfs_fd_destroy (glfd);
+		glfd = NULL;
+	} else {
+		fd_bind (glfd->fd);
+		glfs_fd_bind (glfd);
+	}
+
+	glfs_subvol_done (fs, subvol);
+
+	return glfd;
+}
+
+ssize_t
+glfs_h_extract_handle (struct glfs_object *object, unsigned char *handle,
+		       int len)
+{
+	ssize_t ret = -1;
+
+	/* validate in args */
+	if (object == NULL) {
+		errno = EINVAL;
+		goto out;
+	}
+
+	if (!handle || !len) {
+		ret = GFAPI_HANDLE_LENGTH;
+		goto out;
+	}
+
+	if (len < GFAPI_HANDLE_LENGTH)
+	{
+		errno = ERANGE;
+		goto out;
+	}
+
+	memcpy (handle, object->gfid, GFAPI_HANDLE_LENGTH);
+
+	ret = GFAPI_HANDLE_LENGTH;
+
+out:
+	return ret;
+}
+
+struct glfs_object *
+glfs_h_create_from_handle (struct glfs *fs, unsigned char *handle, int len,
+			   struct stat *stat)
+{
+	loc_t               loc = {0, };
+	int                 ret = -1;
+	struct iatt         iatt = {0, };
+	inode_t            *newinode = NULL;
+	xlator_t           *subvol = NULL;
+	struct glfs_object *object = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (handle == NULL) || (len != GFAPI_HANDLE_LENGTH)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		errno = EIO;
+		goto out;
+	}
+
+	memcpy (loc.gfid, handle, GFAPI_HANDLE_LENGTH);
+
+	newinode = inode_find (subvol->itable, loc.gfid);
+	if (newinode)
+		loc.inode = newinode;
+	else {
+		loc.inode = inode_new (subvol->itable);
+		if (!loc.inode) {
+			errno = ENOMEM;
+			goto out;
+		}
+	}
+
+	ret = syncop_lookup (subvol, &loc, 0, &iatt, 0, 0);
+	if (ret) {
+		gf_log (subvol->name, GF_LOG_WARNING,
+			"inode refresh of %s failed: %s",
+			uuid_utoa (loc.gfid), strerror (errno));
+		goto out;
+	}
+
+	newinode = inode_link (loc.inode, 0, 0, &iatt);
+	if (newinode)
+		inode_lookup (newinode);
+	else {
+		gf_log (subvol->name, GF_LOG_WARNING,
+			"inode linking of %s failed: %s",
+			uuid_utoa (loc.gfid), strerror (errno));
+		errno = EINVAL;
+		goto out;
+	}
+
+	/* populate stat */
+	if (stat)
+		glfs_iatt_to_stat (fs, &iatt, stat);
+
+	object = GF_CALLOC (1, sizeof(struct glfs_object),
+			    glfs_mt_glfs_object_t);
+	if (object == NULL) {
+		errno = ENOMEM;
+		ret = -1;
+		goto out;
+	}
+
+	/* populate the return object */
+	object->inode = newinode;
+	uuid_copy (object->gfid, object->inode->gfid);
+
+out:
+	/* TODO: Check where the inode ref is being held? */
+	loc_wipe (&loc);
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+int
+glfs_h_close (struct glfs_object *object)
+{
+	/* Release the held reference */
+	inode_unref (object->inode);
+	GF_FREE (object);
+
+	return 0;
+}
+
+int
+glfs_h_truncate (struct glfs *fs, struct glfs_object *object, off_t offset)
+{
+	loc_t               loc = {0, };
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_truncate (subvol, &loc, (off_t)offset);
+
+	/* populate out args */
+	if (ret == 0)
+		ret = glfs_loc_unlink (&loc);
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+struct glfs_object *
+glfs_h_symlink (struct glfs *fs, struct glfs_object *parent, const char *name,
+		const char *data, struct stat *stat)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	loc_t               loc = {0, };
+	struct iatt         iatt = {0, };
+	uuid_t              gfid;
+	dict_t             *xattr_req = NULL;
+	struct glfs_object *object = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (parent == NULL) || (name == NULL) ||
+		(data == NULL)) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, parent);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	xattr_req = dict_new ();
+	if (!xattr_req) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	uuid_generate (gfid);
+	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+	if (ret) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_PINODE (inode, loc, ret, errno, out, name);
+
+	/* fop/op */
+	ret = syncop_symlink (subvol, &loc, data, xattr_req, &iatt);
+
+	/* populate out args */
+	if (ret == 0) {
+		/* TODO: If the inode existed in the cache (say file already
+		 * exists), then the glfs_loc_link will not update the
+		 * loc.inode, as a result we will have a 0000 GFID that we
+		 * would copy out to the object, this needs to be fixed.
+		 */
+		ret = glfs_loc_link (&loc, &iatt);
+		if (ret != 0) {
+			goto out;
+		}
+
+		if (stat)
+			glfs_iatt_to_stat (fs, &iatt, stat);
+
+		ret = glfs_create_object (&loc, &object);
+	}
+
+out:
+	if (ret && object != NULL) {
+		glfs_h_close (object);
+		object = NULL;
+	}
+
+	loc_wipe(&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (xattr_req)
+		dict_unref (xattr_req);
+
+	glfs_subvol_done (fs, subvol);
+
+	return object;
+}
+
+int
+glfs_h_readlink (struct glfs *fs, struct glfs_object *object, char *buf,
+		 size_t bufsiz)
+{
+	loc_t               loc = {0, };
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	char               *linkval = NULL;
+
+	/* validate in args */
+	if ((fs == NULL) || (object == NULL) || (buf == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, object);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_INODE (inode, loc, out);
+
+	/* fop/op */
+	ret = syncop_readlink (subvol, &loc, &linkval, bufsiz);
+
+	/* populate out args */
+	if (ret > 0)
+		memcpy (buf, linkval, ret);
+
+out:
+	loc_wipe (&loc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (linkval)
+		GF_FREE (linkval);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+int
+glfs_h_link (struct glfs *fs, struct glfs_object *linksrc,
+	     struct glfs_object *parent, const char *name)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *inode = NULL;
+	inode_t            *pinode = NULL;
+	loc_t               oldloc = {0, };
+	loc_t               newloc = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (linksrc == NULL) || (parent == NULL) ||
+		(name == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	inode = glfs_resolve_inode (fs, subvol, linksrc);
+	if (!inode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	if (inode->ia_type == IA_IFDIR) {
+		ret = -1;
+		errno = EISDIR;
+		goto out;
+	}
+
+	GLFS_LOC_FILL_INODE (inode, oldloc, out);
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	pinode = glfs_resolve_inode (fs, subvol, parent);
+	if (!pinode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	/* setup newloc based on parent */
+	newloc.parent = inode_ref (pinode);
+	newloc.name = name;
+	ret = glfs_loc_touchup (&newloc);
+	if (ret != 0) {
+		errno = EINVAL;
+		goto out;
+	}
+
+	/* Filling the inode of the hard link to be same as that of the
+	 * original file
+	 */
+	newloc.inode = inode_ref (inode);
+
+	/* fop/op */
+	ret = syncop_link (subvol, &oldloc, &newloc);
+
+	if (ret == 0)
+		/* TODO: No iatt to pass as there has been no lookup */
+		ret = glfs_loc_link (&newloc, NULL);
+out:
+	loc_wipe (&oldloc);
+	loc_wipe (&newloc);
+
+	if (inode)
+		inode_unref (inode);
+
+	if (pinode)
+		inode_unref (pinode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
+
+int
+glfs_h_rename (struct glfs *fs, struct glfs_object *olddir, const char *oldname,
+	       struct glfs_object *newdir, const char *newname)
+{
+	int                 ret = -1;
+	xlator_t           *subvol = NULL;
+	inode_t            *oldpinode = NULL;
+	inode_t            *newpinode = NULL;
+	loc_t               oldloc = {0, };
+	loc_t               newloc = {0, };
+	struct iatt         oldiatt = {0, };
+	struct iatt         newiatt = {0, };
+
+	/* validate in args */
+	if ((fs == NULL) || (olddir == NULL) || (oldname == NULL) ||
+		(newdir == NULL) || (newname == NULL)) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	__glfs_entry_fs (fs);
+
+	/* get the active volume */
+	subvol = glfs_active_subvol (fs);
+	if ( !subvol ) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	oldpinode = glfs_resolve_inode (fs, subvol, olddir);
+	if (!oldpinode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	ret = glfs_resolve_at (fs, subvol, oldpinode, oldname, &oldloc,
+			       &oldiatt, 0 , 0);
+	if (ret != 0) {
+		goto out;
+	}
+
+	/* get/refresh the in arg objects inode in correlation to the xlator */
+	newpinode = glfs_resolve_inode (fs, subvol, newdir);
+	if (!newpinode) {
+		errno = ESTALE;
+		goto out;
+	}
+
+	ret = glfs_resolve_at (fs, subvol, newpinode, newname, &newloc,
+			       &newiatt, 0, 0);
+
+	if (ret && errno != ENOENT && newloc.parent)
+		goto out;
+
+	if (newiatt.ia_type != IA_INVAL) {
+		if ((oldiatt.ia_type == IA_IFDIR) !=
+			(newiatt.ia_type == IA_IFDIR)) {
+			/* Either both old and new must be dirs,
+			 * or both must be non-dirs. Else, fail.
+			 */
+			ret = -1;
+			errno = EISDIR;
+			goto out;
+		}
+	}
+
+	/* TODO: check if new or old is a prefix of the other, and fail EINVAL */
+
+	ret = syncop_rename (subvol, &oldloc, &newloc);
+
+	if (ret == 0)
+		inode_rename (oldloc.parent->table, oldloc.parent, oldloc.name,
+			      newloc.parent, newloc.name, oldloc.inode,
+			      &oldiatt);
+
+out:
+	loc_wipe (&oldloc);
+	loc_wipe (&newloc);
+
+	if (oldpinode)
+		inode_unref (oldpinode);
+
+	if (newpinode)
+		inode_unref (newpinode);
+
+	glfs_subvol_done (fs, subvol);
+
+	return ret;
+}
diff --git a/api/src/glfs-handles.h b/api/src/glfs-handles.h
new file mode 100644
index 000000000..437f2cbc8
--- /dev/null
+++ b/api/src/glfs-handles.h
@@ -0,0 +1,143 @@
+/*
+  Copyright (c) 2013 Red Hat, Inc. <http://www.redhat.com>
+  This file is part of GlusterFS.
+
+  This file is licensed to you under your choice of the GNU Lesser
+  General Public License, version 3 or any later version (LGPLv3 or
+  later), or the GNU General Public License, version 2 (GPLv2), in all
+  cases as published by the Free Software Foundation.
+*/
+
+#ifndef _GLFS_HANDLES_H
+#define _GLFS_HANDLES_H
+
+#include "glfs.h"
+
+/* GLFS OBJECT BASED OPERATIONS
+ *
+ * The following APIs are introduced to provide an API framework that can work
+ * with gluster objects (files and directories), instead of absolute paths.
+ *
+ * The following API set can be related to the POSIX *at interfaces (like
+ * openat (2)). The intention of these APIs is to be able to operate based
+ * on parent object and looking up or creating child objects within, OR to be
+ * used on the actual object thus looked up or created, and retrieve information
+ * regarding the same.
+ *
+ * The APIs also provide for generating an opaque invariant handle to the
+ * object, that can later be used to lookup the object, instead of the regular
+ * glfs_h_* variants. The APIs that provide this behaviour are,
+ * glfs_h_extract_handle and glfs_h_create_from_handle.
+ *
+ * The object handles can be transitioned to fd based operations as supported
+ * by glfs.h calls, using the glfs_h_open call. This provides a way to move
+ * from objects to fd's akin to moving from path to fd for required operations.
+ *
+ * NOTE: The opaque invariant handle is the GFID of the object in reality, but
+ * maintained as an opaque data value, for potential internal changes to the
+ * same without impacting the caller.
+ *
+ * NOTE: Currently looking up an object can create multiple object handles to
+ * the same, i.e distinct glfs_object *. Hence each such looked up or received
+ * handle from other calls, would need to be closed. In the future, for a given
+ * object these pointers would be the same, and an ease of use API to forget all
+ * instances of this bject would be provided (instead of a per lookup close).
+ * This should not change the APIs in their current form.
+ *
+ */
+
+/* Values for valid falgs to be used when using XXXsetattr, to set multiple
+ attribute values passed via the related stat structure.
+ */
+#define GFAPI_SET_ATTR_MODE  0x1
+#define GFAPI_SET_ATTR_UID   0x2
+#define GFAPI_SET_ATTR_GID   0x4
+#define GFAPI_SET_ATTR_SIZE  0x8
+#define GFAPI_SET_ATTR_ATIME 0x10
+#define GFAPI_SET_ATTR_MTIME 0x20
+
+/* Handle length for object handles returned from glfs_h_extract_handle or
+ * glfs_h_create_from_handle */
+#define GFAPI_HANDLE_LENGTH 16
+
+__BEGIN_DECLS
+
+/*
+ * Notes:
+ *
+ * The file object handle. One per looked up, created file/directory
+ *
+ * This had been introduced to facilitate gfid/inode based gfapi
+ * - a requirement introduced by nfs-ganesha
+ */
+struct glfs_object;
+typedef struct glfs_object glfs_object_t;
+
+/* Handle based operations */
+/* Operations that generate handles */
+struct glfs_object *glfs_h_lookupat (struct glfs *fs,
+				     struct glfs_object *parent,
+				     const char *path, struct stat *stat);
+
+struct glfs_object *glfs_h_creat (struct glfs *fs, struct glfs_object *parent,
+				  const char *path, int flags, mode_t mode,
+				  struct stat *sb);
+
+struct glfs_object *glfs_h_mkdir (struct glfs *fs, struct glfs_object *parent,
+				  const char *path, mode_t flags,
+				  struct stat *sb);
+
+struct glfs_object *glfs_h_mknod (struct glfs *fs, struct glfs_object *parent,
+				  const char *path, mode_t mode, dev_t dev,
+				  struct stat *sb);
+
+struct glfs_object *glfs_h_symlink (struct glfs *fs, struct glfs_object *parent,
+				    const char *name, const char *data,
+				    struct stat *stat);
+
+/* Operations on the actual objects */
+int glfs_h_unlink (struct glfs *fs, struct glfs_object *parent,
+		   const char *path);
+
+int glfs_h_close (struct glfs_object *object);
+
+int glfs_caller_specific_init (void *uid_caller_key, void *gid_caller_key,
+			       void *future);
+
+int glfs_h_truncate (struct glfs *fs, struct glfs_object *object, off_t offset);
+
+int glfs_h_stat(struct glfs *fs, struct glfs_object *object, struct stat *stat);
+
+int glfs_h_getattrs (struct glfs *fs, struct glfs_object *object,
+		     struct stat *stat);
+
+int glfs_h_setattrs (struct glfs *fs, struct glfs_object *object,
+		     struct stat *sb, int valid);
+
+int glfs_h_readlink (struct glfs *fs, struct glfs_object *object, char *buf,
+		     size_t bufsiz);
+
+int glfs_h_link (struct glfs *fs, struct glfs_object *linktgt,
+		 struct glfs_object *parent, const char *name);
+
+int glfs_h_rename (struct glfs *fs, struct glfs_object *olddir,
+		   const char *oldname, struct glfs_object *newdir,
+		   const char *newname);
+
+/* Operations enabling opaque invariant handle to object transitions */
+ssize_t glfs_h_extract_handle (struct glfs_object *object,
+			       unsigned char *handle, int len);
+
+struct glfs_object *glfs_h_create_from_handle (struct glfs *fs,
+					       unsigned char *handle, int len,
+					       struct stat *stat);
+
+/* Operations enabling object handles to fd transitions */
+struct glfs_fd *glfs_h_opendir (struct glfs *fs, struct glfs_object *object);
+
+struct glfs_fd *glfs_h_open (struct glfs *fs, struct glfs_object *object,
+			     int flags);
+
+__END_DECLS
+
+#endif /* !_GLFS_HANDLES_H */
+\ No newline at end of file
diff --git a/api/src/glfs-internal.h b/api/src/glfs-internal.h
index c2fc0ecc1..ec1d5579d 100644
--- a/api/src/glfs-internal.h
+++ b/api/src/glfs-internal.h
@@ -14,6 +14,46 @@
 
 #include "xlator.h"
 
+#define GLFS_SYMLINK_MAX_FOLLOW 2048
+
+#define DEFAULT_REVAL_COUNT 1
+
+#define ESTALE_RETRY(ret,errno,reval,loc,label) do {	\
+	if (ret == -1 && errno == ESTALE) {	        \
+		if (reval < DEFAULT_REVAL_COUNT) {	\
+			reval++;			\
+			loc_wipe (loc);			\
+			goto label;			\
+		}					\
+	}						\
+	} while (0)
+
+#define GLFS_LOC_FILL_INODE(oinode, loc, label) do {   \
+	loc.inode = inode_ref (oinode);                \
+	uuid_copy (loc.gfid, oinode->gfid);            \
+	ret = glfs_loc_touchup (&loc);                 \
+	if (ret != 0) {                                \
+		errno = EINVAL;                        \
+		goto label;                            \
+	}                                              \
+	} while (0)
+
+#define GLFS_LOC_FILL_PINODE(pinode, loc, ret, errno, label, path) do {   \
+	loc.inode = inode_new (pinode->table);                            \
+	if (!loc.inode) {                                                 \
+		ret = -1;                                                 \
+		errno = ENOMEM;                                           \
+		goto label;                                               \
+	}                                                                 \
+	loc.parent = inode_ref (pinode);                                  \
+	loc.name = path;                                                  \
+	ret = glfs_loc_touchup (&loc);                                    \
+	if (ret != 0) {                                                   \
+		errno = EINVAL;                                           \
+		goto label;                                               \
+	}                                                                 \
+	} while (0)
+
 struct glfs;
 
 typedef int (*glfs_init_cbk) (struct glfs *fs, int ret);
@@ -33,16 +73,37 @@ struct glfs {
 	int                 err;
 
 	xlator_t           *active_subvol;
+	xlator_t           *next_subvol;
+	xlator_t           *old_subvol;
 
 	char               *oldvolfile;
 	ssize_t             oldvollen;
+
+	inode_t            *cwd;
+
+	uint32_t            dev_id; /* Used to fill st_dev in struct stat */
+
+	struct list_head    openfds;
+
+	gf_boolean_t        migration_in_progress;
 };
 
 struct glfs_fd {
+	struct list_head   openfds;
+	struct glfs       *fs;
 	off_t              offset;
-	fd_t              *fd;
+	fd_t              *fd; /* Currently guared by @fs->mutex. TODO: per-glfd lock */
 	struct list_head   entries;
 	gf_dirent_t       *next;
+	struct dirent     *readdirbuf;
+};
+
+/* glfs object handle introduced for the alternate gfapi implementation based
+   on glfs handles/gfid/inode
+*/
+struct glfs_object {
+        inode_t         *inode;
+        uuid_t          gfid;
 };
 
 #define DEFAULT_EVENT_POOL_SIZE           16384
@@ -54,10 +115,14 @@ int glfs_mgmt_init (struct glfs *fs);
 void glfs_init_done (struct glfs *fs, int ret);
 int glfs_process_volfp (struct glfs *fs, FILE *fp);
 int glfs_resolve (struct glfs *fs, xlator_t *subvol, const char *path, loc_t *loc,
-		  struct iatt *iatt);
+		  struct iatt *iatt, int reval);
 int glfs_lresolve (struct glfs *fs, xlator_t *subvol, const char *path, loc_t *loc,
-		   struct iatt *iatt);
-void glfs_first_lookup (xlator_t *subvol);
+		   struct iatt *iatt, int reval);
+fd_t *glfs_resolve_fd (struct glfs *fs, xlator_t *subvol, struct glfs_fd *glfd);
+
+fd_t *__glfs_migrate_fd (struct glfs *fs, xlator_t *subvol, struct glfs_fd *glfd);
+
+int glfs_first_lookup (xlator_t *subvol);
 
 static inline void
 __glfs_entry_fs (struct glfs *fs)
@@ -73,10 +138,63 @@ __glfs_entry_fd (struct glfs_fd *fd)
 }
 
 
+/*
+  By default all lock attempts from user context must
+  use glfs_lock() and glfs_unlock(). This allows
+  for a safe implementation of graph migration where
+  we can give up the mutex during syncop calls so
+  that bottom up calls (particularly CHILD_UP notify)
+  can do a mutex_lock() on @glfs without deadlocking
+  the filesystem
+*/
+static inline int
+glfs_lock (struct glfs *fs)
+{
+	pthread_mutex_lock (&fs->mutex);
+
+	while (!fs->init)
+		pthread_cond_wait (&fs->cond, &fs->mutex);
+
+	while (fs->migration_in_progress)
+		pthread_cond_wait (&fs->cond, &fs->mutex);
+
+	return 0;
+}
+
+
+static inline void
+glfs_unlock (struct glfs *fs)
+{
+	pthread_mutex_unlock (&fs->mutex);
+}
+
+
 void glfs_fd_destroy (struct glfs_fd *glfd);
 
-xlator_t * glfs_fd_subvol (struct glfs_fd *glfd);
+struct glfs_fd *glfs_fd_new (struct glfs *fs);
+void glfs_fd_bind (struct glfs_fd *glfd);
 
 xlator_t * glfs_active_subvol (struct glfs *fs);
+xlator_t * __glfs_active_subvol (struct glfs *fs);
+void glfs_subvol_done (struct glfs *fs, xlator_t *subvol);
+
+inode_t * glfs_refresh_inode (xlator_t *subvol, inode_t *inode);
+
+inode_t *glfs_cwd_get (struct glfs *fs);
+int glfs_cwd_set (struct glfs *fs, inode_t *inode);
+inode_t *glfs_resolve_inode (struct glfs *fs, xlator_t *subvol,
+			     struct glfs_object *object);
+int glfs_create_object (loc_t *loc, struct glfs_object **retobject);
+int __glfs_cwd_set (struct glfs *fs, inode_t *inode);
+
+int glfs_resolve_base (struct glfs *fs, xlator_t *subvol, inode_t *inode,
+		       struct iatt *iatt);
+int glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
+                     const char *origpath, loc_t *loc, struct iatt *iatt,
+                     int follow, int reval);
+int glfs_loc_touchup (loc_t *loc);
+void glfs_iatt_to_stat (struct glfs *fs, struct iatt *iatt, struct stat *stat);
+int glfs_loc_link (loc_t *loc, struct iatt *iatt);
+int glfs_loc_unlink (loc_t *loc);
 
 #endif /* !_GLFS_INTERNAL_H */
diff --git a/api/src/glfs-master.c b/api/src/glfs-master.c
index 0806c3077..c02534c18 100644
--- a/api/src/glfs-master.c
+++ b/api/src/glfs-master.c
@@ -22,26 +22,58 @@
 
 #include "xlator.h"
 #include "glusterfs.h"
+
 #include "glfs-internal.h"
+#include "glfs-mem-types.h"
 
 
 int
 glfs_graph_setup (struct glfs *fs, glusterfs_graph_t *graph)
 {
-	if (fs->active_subvol == graph->top)
-		return 0;
+	xlator_t      *new_subvol = NULL;
+	xlator_t      *old_subvol = NULL;
+	inode_table_t *itable = NULL;
+	int            ret = -1;
+
+	new_subvol = graph->top;
 
+	/* This is called in a bottom-up context, it should specifically
+	   NOT be glfs_lock()
+	*/
 	pthread_mutex_lock (&fs->mutex);
 	{
-		fs->active_subvol = graph->top;
-		pthread_cond_broadcast (&fs->cond);
+		if (new_subvol->switched ||
+		    new_subvol == fs->active_subvol ||
+		    new_subvol == fs->next_subvol) {
+			/* Spurious CHILD_UP event on old graph */
+			ret = 0;
+			goto unlock;
+		}
+
+		if (!new_subvol->itable) {
+			itable = inode_table_new (131072, new_subvol);
+			if (!itable) {
+				errno = ENOMEM;
+				ret = -1;
+				goto unlock;
+			}
+
+			new_subvol->itable = itable;
+		}
+
+		old_subvol = fs->next_subvol;
+		fs->next_subvol = new_subvol;
+		fs->next_subvol->winds++; /* first ref */
+		ret = 0;
 	}
+unlock:
 	pthread_mutex_unlock (&fs->mutex);
 
-	gf_log ("glfs-master", GF_LOG_INFO, "switched to graph %s (%d)",
-		uuid_utoa ((unsigned char *)graph->graph_uuid), graph->id);
+	if (old_subvol)
+		/* wasn't picked up so far, skip */
+		glfs_subvol_done (fs, old_subvol);
 
-	return 0;
+	return ret;
 }
 
 
@@ -83,6 +115,18 @@ notify (xlator_t *this, int event, void *data, ...)
 int
 mem_acct_init (xlator_t *this)
 {
+	int ret = -1;
+
+	if (!this)
+		return ret;
+
+	ret = xlator_mem_acct_init (this, glfs_mt_end + 1);
+	if (ret) {
+		gf_log (this->name, GF_LOG_ERROR, "Failed to initialise "
+                        "memory accounting");
+		return ret;
+	}
+
 	return 0;
 }
 
@@ -101,13 +145,10 @@ fini (xlator_t *this)
 }
 
 
-struct xlator_dumpops dumpops = {
-};
+struct xlator_dumpops dumpops;
 
 
-struct xlator_fops fops = {
-};
+struct xlator_fops fops;
 
 
-struct xlator_cbks cbks = {
-};
+struct xlator_cbks cbks;
diff --git a/api/src/glfs-mem-types.h b/api/src/glfs-mem-types.h
index e2e9b4c1e..3301b3da5 100644
--- a/api/src/glfs-mem-types.h
+++ b/api/src/glfs-mem-types.h
@@ -16,13 +16,16 @@
 #define GF_MEM_TYPE_START (gf_common_mt_end + 1)
 
 enum glfs_mem_types_ {
-        glfs_mt_glfs_t,
+        glfs_mt_glfs_t = GF_MEM_TYPE_START,
         glfs_mt_call_pool_t,
         glfs_mt_xlator_t,
 	glfs_mt_glfs_fd_t,
 	glfs_mt_glfs_io_t,
 	glfs_mt_volfile_t,
-        glfs_mt_end
+	glfs_mt_xlator_cmdline_option_t,
+	glfs_mt_glfs_object_t,
+	glfs_mt_readdirbuf_t,
+	glfs_mt_end
 
 };
 #endif
diff --git a/api/src/glfs-mgmt.c b/api/src/glfs-mgmt.c
index 2ead93863..6843e9cb3 100644
--- a/api/src/glfs-mgmt.c
+++ b/api/src/glfs-mgmt.c
@@ -114,7 +114,7 @@ mgmt_cbk_event (struct rpc_clnt *rpc, void *mydata, void *data)
 }
 
 
-rpcclnt_cb_actor_t gluster_cbk_actors[] = {
+rpcclnt_cb_actor_t mgmt_cbk_actors[] = {
 	[GF_CBK_FETCHSPEC] = {"FETCHSPEC", GF_CBK_FETCHSPEC, mgmt_cbk_spec },
 	[GF_CBK_EVENT_NOTIFY] = {"EVENTNOTIFY", GF_CBK_EVENT_NOTIFY,
 				 mgmt_cbk_event},
@@ -125,7 +125,7 @@ struct rpcclnt_cb_program mgmt_cbk_prog = {
 	.progname  = "GlusterFS Callback",
 	.prognum   = GLUSTER_CBK_PROGRAM,
 	.progver   = GLUSTER_CBK_VERSION,
-	.actors	   = gluster_cbk_actors,
+	.actors	   = mgmt_cbk_actors,
 	.numactors = GF_CBK_MAXVALUE,
 };
 
@@ -203,162 +203,6 @@ out:
 
 
 static int
-xlator_equal_rec (xlator_t *xl1, xlator_t *xl2)
-{
-	xlator_list_t *trav1 = NULL;
-	xlator_list_t *trav2 = NULL;
-	int	       ret   = 0;
-
-	if (xl1 == NULL || xl2 == NULL) {
-		gf_log ("xlator", GF_LOG_DEBUG, "invalid argument");
-		return -1;
-	}
-
-	trav1 = xl1->children;
-	trav2 = xl2->children;
-
-	while (trav1 && trav2) {
-		ret = xlator_equal_rec (trav1->xlator, trav2->xlator);
-		if (ret) {
-			gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-				"xlators children not equal");
-			goto out;
-		}
-
-		trav1 = trav1->next;
-		trav2 = trav2->next;
-	}
-
-	if (trav1 || trav2) {
-		ret = -1;
-		goto out;
-	}
-
-	if (strcmp (xl1->name, xl2->name)) {
-		ret = -1;
-		goto out;
-	}
-out :
-	return ret;
-}
-
-
-static gf_boolean_t
-is_graph_topology_equal (glusterfs_graph_t *graph1,
-			 glusterfs_graph_t *graph2)
-{
-	xlator_t    *trav1    = NULL;
-	xlator_t    *trav2    = NULL;
-	gf_boolean_t ret      = _gf_true;
-
-	trav1 = graph1->first;
-	trav2 = graph2->first;
-
-	ret = xlator_equal_rec (trav1, trav2);
-
-	if (ret) {
-		gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-			"graphs are not equal");
-		ret = _gf_false;
-		goto out;
-	}
-
-	ret = _gf_true;
-	gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-		"graphs are equal");
-
-out:
-	return ret;
-}
-
-
-/* Function has 3types of return value 0, -ve , 1
- *   return 0	       =======> reconfiguration of options has succeeded
- *   return 1	       =======> the graph has to be reconstructed and all the xlators should be inited
- *   return -1(or -ve) =======> Some Internal Error occurred during the operation
- */
-static int
-glusterfs_volfile_reconfigure (struct glfs *fs, FILE *newvolfile_fp)
-{
-	glusterfs_graph_t *oldvolfile_graph = NULL;
-	glusterfs_graph_t *newvolfile_graph = NULL;
-	FILE		  *oldvolfile_fp    = NULL;
-	glusterfs_ctx_t	  *ctx		    = NULL;
-
-	int ret = -1;
-
-	oldvolfile_fp = tmpfile ();
-	if (!oldvolfile_fp)
-		goto out;
-
-	if (!fs->oldvollen) {
-		ret = 1; // Has to call INIT for the whole graph
-		goto out;
-	}
-	fwrite (fs->oldvolfile, fs->oldvollen, 1, oldvolfile_fp);
-	fflush (oldvolfile_fp);
-	if (ferror (oldvolfile_fp)) {
-		goto out;
-	}
-
-	oldvolfile_graph = glusterfs_graph_construct (oldvolfile_fp);
-	if (!oldvolfile_graph) {
-		goto out;
-	}
-
-	newvolfile_graph = glusterfs_graph_construct (newvolfile_fp);
-	if (!newvolfile_graph) {
-		goto out;
-	}
-
-	if (!is_graph_topology_equal (oldvolfile_graph,
-				      newvolfile_graph)) {
-
-		ret = 1;
-		gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-			"Graph topology not equal(should call INIT)");
-		goto out;
-	}
-
-	gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-		"Only options have changed in the new "
-		"graph");
-
-	ctx = fs->ctx;
-
-	if (!ctx) {
-		gf_log ("glfs-mgmt", GF_LOG_ERROR,
-			"glusterfs_ctx_get() returned NULL");
-		goto out;
-	}
-
-	oldvolfile_graph = ctx->active;
-
-	if (!oldvolfile_graph) {
-		gf_log ("glfs-mgmt", GF_LOG_ERROR,
-			"glusterfs_ctx->active is NULL");
-		goto out;
-	}
-
-	/* */
-	ret = glusterfs_graph_reconfigure (oldvolfile_graph,
-					   newvolfile_graph);
-	if (ret) {
-		gf_log ("glfs-mgmt", GF_LOG_DEBUG,
-			"Could not reconfigure new options in old graph");
-		goto out;
-	}
-
-	ret = 0;
-out:
-	if (oldvolfile_fp)
-		fclose (oldvolfile_fp);
-
-	return ret;
-}
-
-
-static int
 glusterfs_oldvolfile_update (struct glfs *fs, char *volfile, ssize_t size)
 {
 	int ret = -1;
@@ -416,6 +260,7 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
 		gf_log (frame->this->name, GF_LOG_ERROR,
 			"failed to get the 'volume file' from server");
 		ret = -1;
+                errno = rsp.op_errno;
 		goto out;
 	}
 
@@ -450,7 +295,8 @@ mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
 	*  return -1(or -ve) =======> Some Internal Error occurred during the operation
 	*/
 
-	ret = glusterfs_volfile_reconfigure (fs, tmpfp);
+	ret = glusterfs_volfile_reconfigure (fs->oldvollen, tmpfp, fs->ctx,
+                                             fs->oldvolfile);
 	if (ret == 0) {
 		gf_log ("glusterfsd-mgmt", GF_LOG_DEBUG,
 			"No need to re-load volfile, reconfigure done");
@@ -477,6 +323,14 @@ out:
 	if (rsp.spec)
 		free (rsp.spec);
 
+        // Stop if server is running at an unsupported op-version
+        if (ENOTSUP == ret) {
+                gf_log ("mgmt", GF_LOG_ERROR, "Server is operating at an "
+                        "op-version which is not supported");
+                errno = ENOTSUP;
+                glfs_init_done (fs, -1);
+        }
+
 	if (ret && ctx && !ctx->active) {
 		/* Do it only for the first time */
 		/* Failed to get the volume file, something wrong,
@@ -484,8 +338,11 @@ out:
 		gf_log ("glfs-mgmt", GF_LOG_ERROR,
 			"failed to fetch volume file (key:%s)",
 			ctx->cmd_args.volfile_id);
-		if (!need_retry)
+		if (!need_retry) {
+                        if (!errno)
+                                errno = EINVAL;
 			glfs_init_done (fs, -1);
+                }
 	}
 
 	if (tmpfp)
@@ -503,6 +360,7 @@ glfs_volfile_fetch (struct glfs *fs)
 	int		  ret = 0;
 	call_frame_t	 *frame = NULL;
 	glusterfs_ctx_t	 *ctx = NULL;
+        dict_t           *dict = NULL;
 
 	ctx = fs->ctx;
 	cmd_args = &ctx->cmd_args;
@@ -512,10 +370,41 @@ glfs_volfile_fetch (struct glfs *fs)
 	req.key = cmd_args->volfile_id;
 	req.flags = 0;
 
+        dict = dict_new ();
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        // Set the supported min and max op-versions, so glusterd can make a
+        // decision
+        ret = dict_set_int32 (dict, "min-op-version", GD_OP_VERSION_MIN);
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_ERROR, "Failed to set min-op-version"
+                        " in request dict");
+                goto out;
+        }
+
+        ret = dict_set_int32 (dict, "max-op-version", GD_OP_VERSION_MAX);
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_ERROR, "Failed to set max-op-version"
+                        " in request dict");
+                goto out;
+        }
+
+        ret = dict_allocate_and_serialize (dict, &req.xdata.xdata_val,
+                                           &req.xdata.xdata_len);
+        if (ret < 0) {
+                gf_log (THIS->name, GF_LOG_ERROR,
+                        "Failed to serialize dictionary");
+                goto out;
+        }
+
 	ret = mgmt_submit_request (&req, frame, ctx, &clnt_handshake_prog,
 				   GF_HNDSK_GETSPEC, mgmt_getspec_cbk,
 				   (xdrproc_t)xdr_gf_getspec_req);
-	return ret;
+out:
+        return ret;
 }
 
 
@@ -544,9 +433,10 @@ mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
 			gf_log ("glfs-mgmt", GF_LOG_INFO,
 				"%d connect attempts left",
 				cmd_args->max_connect_attempts);
-			if (0 >= cmd_args->max_connect_attempts)
+			if (0 >= cmd_args->max_connect_attempts) {
+                                errno = ENOTCONN;
 				glfs_init_done (fs, -1);
-				break;
+                        }
 		}
 		break;
 	case RPC_CLNT_CONNECT:
@@ -555,10 +445,11 @@ mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
 		ret = glfs_volfile_fetch (fs);
 		if (ret && ctx && (ctx->active == NULL)) {
 			/* Do it only for the first time */
-			/* Exit the process.. there is some wrong options */
+			/* Exit the process.. there are some wrong options */
 			gf_log ("glfs-mgmt", GF_LOG_ERROR,
 				"failed to fetch volume file (key:%s)",
 				ctx->cmd_args.volfile_id);
+                        errno = EINVAL;
 			glfs_init_done (fs, -1);
 		}
 
diff --git a/api/src/glfs-resolve.c b/api/src/glfs-resolve.c
index f7754d201..4ca2eb6fc 100644
--- a/api/src/glfs-resolve.c
+++ b/api/src/glfs-resolve.c
@@ -32,9 +32,11 @@
 
 #include "glfs-internal.h"
 
+#define graphid_str(subvol) (uuid_utoa((unsigned char *)subvol->graph->graph_uuid))
 
-void
-glfs_first_lookup (xlator_t *subvol)
+
+int
+glfs_first_lookup_safe (xlator_t *subvol)
 {
 	loc_t  loc = {0, };
 	int    ret = -1;
@@ -49,10 +51,89 @@ glfs_first_lookup (xlator_t *subvol)
 
 	gf_log (subvol->name, GF_LOG_DEBUG, "first lookup complete %d", ret);
 
-	return;
+	return ret;
+}
+
+
+int
+__glfs_first_lookup (struct glfs *fs, xlator_t *subvol)
+{
+	int ret = -1;
+
+	fs->migration_in_progress = 1;
+	pthread_mutex_unlock (&fs->mutex);
+	{
+		ret = glfs_first_lookup_safe (subvol);
+	}
+	pthread_mutex_lock (&fs->mutex);
+	fs->migration_in_progress = 0;
+	pthread_cond_broadcast (&fs->cond);
+
+	return ret;
+}
+
+
+inode_t *
+glfs_refresh_inode_safe (xlator_t *subvol, inode_t *oldinode)
+{
+	loc_t        loc = {0, };
+	int          ret = -1;
+	struct iatt  iatt = {0, };
+	inode_t     *newinode = NULL;
+
+
+	if (!oldinode)
+		return NULL;
+
+	if (oldinode->table->xl == subvol)
+		return inode_ref (oldinode);
+
+	newinode = inode_find (subvol->itable, oldinode->gfid);
+	if (newinode)
+		return newinode;
+
+	uuid_copy (loc.gfid, oldinode->gfid);
+	loc.inode = inode_new (subvol->itable);
+	if (!loc.inode)
+		return NULL;
+
+	ret = syncop_lookup (subvol, &loc, 0, &iatt, 0, 0);
+
+	if (ret) {
+		gf_log (subvol->name, GF_LOG_WARNING,
+			"inode refresh of %s failed: %s",
+			uuid_utoa (oldinode->gfid), strerror (errno));
+		loc_wipe (&loc);
+		return NULL;
+	}
+
+	newinode = inode_link (loc.inode, 0, 0, &iatt);
+	if (newinode)
+		inode_lookup (newinode);
+
+	loc_wipe (&loc);
+
+	return newinode;
 }
 
 
+inode_t *
+__glfs_refresh_inode (struct glfs *fs, xlator_t *subvol, inode_t *inode)
+{
+	inode_t *newinode = NULL;
+
+	fs->migration_in_progress = 1;
+	pthread_mutex_unlock (&fs->mutex);
+	{
+		newinode = glfs_refresh_inode_safe (subvol, inode);
+	}
+	pthread_mutex_lock (&fs->mutex);
+	fs->migration_in_progress = 0;
+	pthread_cond_broadcast (&fs->cond);
+
+	return newinode;
+}
+
 int
 glfs_loc_touchup (loc_t *loc)
 {
@@ -60,7 +141,10 @@ glfs_loc_touchup (loc_t *loc)
 	int   ret = -1;
 	char *bn = NULL;
 
-	ret = inode_path (loc->parent, loc->name, &path);
+	if (loc->parent)
+		ret = inode_path (loc->parent, loc->name, &path);
+	else
+		ret = inode_path (loc->inode, 0, &path);
 
 	loc->path = path;
 
@@ -98,7 +182,7 @@ glfs_resolve_symlink (struct glfs *fs, xlator_t *subvol, inode_t *inode,
 
 	ret = syncop_readlink (subvol, &loc, &path, 4096);
 
-	if (ret)
+	if (ret < 0)
 		goto out;
 
 	if (lpath)
@@ -109,7 +193,7 @@ out:
 }
 
 
-void
+int
 glfs_resolve_base (struct glfs *fs, xlator_t *subvol, inode_t *inode,
 		   struct iatt *iatt)
 {
@@ -128,12 +212,15 @@ glfs_resolve_base (struct glfs *fs, xlator_t *subvol, inode_t *inode,
 	ret = syncop_lookup (subvol, &loc, NULL, iatt, NULL, NULL);
 out:
 	loc_wipe (&loc);
+
+	return ret;
 }
 
 
 inode_t *
 glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
-			const char *component, struct iatt *iatt)
+			const char *component, struct iatt *iatt,
+			int force_lookup)
 {
 	loc_t        loc = {0, };
 	inode_t     *inode = NULL;
@@ -149,23 +236,23 @@ glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
 	loc.parent = inode_ref (parent);
 	uuid_copy (loc.pargfid, parent->gfid);
 
-	xattr_req = dict_new ();
-	if (!xattr_req) {
-		errno = ENOMEM;
-		goto out;
-	}
-
-	ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
-	if (ret) {
-		errno = ENOMEM;
-		goto out;
-	}
 
-	loc.inode = inode_grep (parent->table, parent, component);
+	if (strcmp (component, ".") == 0)
+		loc.inode = inode_ref (parent);
+	else if (strcmp (component, "..") == 0)
+		loc.inode = inode_parent (parent, 0, 0);
+	else
+		loc.inode = inode_grep (parent->table, parent, component);
 
 	if (loc.inode) {
 		uuid_copy (loc.gfid, loc.inode->gfid);
 		reval = 1;
+
+		if (!force_lookup) {
+			inode = inode_ref (loc.inode);
+			ciatt.ia_type = inode->ia_type;
+			goto found;
+		}
 	} else {
 		uuid_generate (gfid);
 		loc.inode = inode_new (parent->table);
@@ -174,20 +261,35 @@ glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
 	if (!loc.inode)
 		goto out;
 
-
 	glret = glfs_loc_touchup (&loc);
 	if (glret < 0) {
 		ret = -1;
 		goto out;
 	}
 
-	ret = syncop_lookup (subvol, &loc, xattr_req, &ciatt, NULL, NULL);
+	ret = syncop_lookup (subvol, &loc, NULL, &ciatt, NULL, NULL);
 	if (ret && reval) {
 		inode_unref (loc.inode);
 		loc.inode = inode_new (parent->table);
-		if (!loc.inode)
+		if (!loc.inode) {
+			errno = ENOMEM;
 			goto out;
+		}
+
+		xattr_req = dict_new ();
+		if (!xattr_req) {
+			errno = ENOMEM;
+			goto out;
+		}
+
 		uuid_generate (gfid);
+
+		ret = dict_set_static_bin (xattr_req, "gfid-req", gfid, 16);
+		if (ret) {
+			errno = ENOMEM;
+			goto out;
+		}
+
 		ret = syncop_lookup (subvol, &loc, xattr_req, &ciatt,
 				     NULL, NULL);
 	}
@@ -195,13 +297,14 @@ glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
 		goto out;
 
 	inode = inode_link (loc.inode, loc.parent, component, &ciatt);
+found:
 	if (inode)
 		inode_lookup (inode);
 	if (iatt)
 		*iatt = ciatt;
 out:
 	if (xattr_req)
-		dict_destroy (xattr_req);
+		dict_unref (xattr_req);
 
 	loc_wipe (&loc);
 
@@ -212,7 +315,7 @@ out:
 int
 glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
 		 const char *origpath, loc_t *loc, struct iatt *iatt,
-		 int follow)
+		 int follow, int reval)
 {
 	inode_t    *inode = NULL;
 	inode_t    *parent = NULL;
@@ -238,7 +341,8 @@ glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
 	} else {
 		inode = inode_ref (subvol->itable->root);
 
-		glfs_resolve_base (fs, subvol, inode, &ciatt);
+		if (strcmp (path, "/") == 0)
+			glfs_resolve_base (fs, subvol, inode, &ciatt);
 	}
 
 	for (component = strtok_r (path, "/", &saveptr);
@@ -252,7 +356,13 @@ glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
 		parent = inode;
 
 		inode = glfs_resolve_component (fs, subvol, parent,
-						component, &ciatt);
+						component, &ciatt,
+						/* force hard lookup on the last
+						   component, as the caller
+						   wants proper iatt filled
+						*/
+						(reval || (!next_component &&
+						iatt)));
 		if (!inode)
 			break;
 
@@ -264,6 +374,16 @@ glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
 			char *lpath = NULL;
 			loc_t sym_loc = {0,};
 
+			if (follow > GLFS_SYMLINK_MAX_FOLLOW) {
+				errno = ELOOP;
+				ret = -1;
+				if (inode) {
+					inode_unref (inode);
+					inode = NULL;
+				}
+				break;
+			}
+
 			ret = glfs_resolve_symlink (fs, subvol, inode, &lpath);
 			inode_unref (inode);
 			inode = NULL;
@@ -279,7 +399,7 @@ glfs_resolve_at (struct glfs *fs, xlator_t *subvol, inode_t *at,
 					       /* always recurisvely follow while
 						  following symlink
 					       */
-					       1);
+					       follow + 1, reval);
 			if (ret == 0)
 				inode = inode_ref (sym_loc.inode);
 			loc_wipe (&sym_loc);
@@ -335,12 +455,34 @@ out:
 
 
 int
+glfs_resolve_path (struct glfs *fs, xlator_t *subvol, const char *origpath,
+		   loc_t *loc, struct iatt *iatt, int follow, int reval)
+{
+	int ret = -1;
+	inode_t *cwd = NULL;
+
+	if (origpath[0] == '/')
+		return glfs_resolve_at (fs, subvol, NULL, origpath, loc, iatt,
+					follow, reval);
+
+	cwd = glfs_cwd_get (fs);
+
+	ret = glfs_resolve_at (fs, subvol, cwd, origpath, loc, iatt,
+			       follow, reval);
+	if (cwd)
+		inode_unref (cwd);
+
+	return ret;
+}
+
+
+int
 glfs_resolve (struct glfs *fs, xlator_t *subvol, const char *origpath,
-	      loc_t *loc, struct iatt *iatt)
+	      loc_t *loc, struct iatt *iatt, int reval)
 {
 	int ret = -1;
 
-	ret = glfs_resolve_at (fs, subvol, NULL, origpath, loc, iatt, 1);
+	ret = glfs_resolve_path (fs, subvol, origpath, loc, iatt, 1, reval);
 
 	return ret;
 }
@@ -348,12 +490,480 @@ glfs_resolve (struct glfs *fs, xlator_t *subvol, const char *origpath,
 
 int
 glfs_lresolve (struct glfs *fs, xlator_t *subvol, const char *origpath,
-	       loc_t *loc, struct iatt *iatt)
+	       loc_t *loc, struct iatt *iatt, int reval)
+{
+	int ret = -1;
+
+	ret = glfs_resolve_path (fs, subvol, origpath, loc, iatt, 0, reval);
+
+	return ret;
+}
+
+
+int
+glfs_migrate_fd_locks_safe (struct glfs *fs, xlator_t *oldsubvol, fd_t *oldfd,
+			    xlator_t *newsubvol, fd_t *newfd)
+{
+	dict_t *lockinfo = NULL;
+	int ret = 0;
+	char uuid1[64];
+
+	if (!oldfd->lk_ctx || fd_lk_ctx_empty (oldfd->lk_ctx))
+		return 0;
+
+	newfd->lk_ctx = fd_lk_ctx_ref (oldfd->lk_ctx);
+
+	ret = syncop_fgetxattr (oldsubvol, oldfd, &lockinfo,
+				GF_XATTR_LOCKINFO_KEY);
+	if (ret < 0) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"fgetxattr (%s) failed (%s) on graph %s (%d)",
+			uuid_utoa_r (oldfd->inode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (oldsubvol), oldsubvol->graph->id);
+		goto out;
+	}
+
+	if (!dict_get (lockinfo, GF_XATTR_LOCKINFO_KEY)) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"missing lokinfo key (%s) on graph %s (%d)",
+			uuid_utoa_r (oldfd->inode->gfid, uuid1),
+			graphid_str (oldsubvol), oldsubvol->graph->id);
+		goto out;
+	}
+
+	ret = syncop_fsetxattr (newsubvol, newfd, lockinfo, 0);
+	if (ret < 0) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"fsetxattr (%s) failed (%s) on graph %s (%d)",
+			uuid_utoa_r (newfd->inode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (newsubvol), newsubvol->graph->id);
+		goto out;
+	}
+out:
+	if (lockinfo)
+		dict_unref (lockinfo);
+	return ret;
+}
+
+
+fd_t *
+glfs_migrate_fd_safe (struct glfs *fs, xlator_t *newsubvol, fd_t *oldfd)
 {
+	fd_t *newfd = NULL;
+	inode_t *oldinode = NULL;
+	inode_t *newinode = NULL;
+	xlator_t *oldsubvol = NULL;
 	int ret = -1;
+	loc_t loc = {0, };
+	char uuid1[64];
+
+
+	oldinode = oldfd->inode;
+	oldsubvol = oldinode->table->xl;
+
+	if (oldsubvol == newsubvol)
+		return fd_ref (oldfd);
+
+	if (!oldsubvol->switched) {
+		ret = syncop_fsync (oldsubvol, oldfd, 0);
+		if (ret) {
+			gf_log (fs->volname, GF_LOG_WARNING,
+				"fsync() failed (%s) on %s graph %s (%d)",
+				strerror (errno),
+				uuid_utoa_r (oldfd->inode->gfid, uuid1),
+				graphid_str (oldsubvol), oldsubvol->graph->id);
+		}
+	}
+
+	newinode = glfs_refresh_inode_safe (newsubvol, oldinode);
+	if (!newinode) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"inode (%s) refresh failed (%s) on graph %s (%d)",
+			uuid_utoa_r (oldinode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (newsubvol), newsubvol->graph->id);
+		goto out;
+	}
+
+	newfd = fd_create (newinode, getpid());
+	if (!newfd) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"fd_create (%s) failed (%s) on graph %s (%d)",
+			uuid_utoa_r (newinode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (newsubvol), newsubvol->graph->id);
+		goto out;
+	}
+
+	loc.inode = inode_ref (newinode);
+
+        ret = inode_path (oldfd->inode, NULL, (char **)&loc.path);
+        if (ret < 0) {
+                gf_log (fs->volname, GF_LOG_INFO, "inode_path failed");
+                goto out;
+        }
+
+        uuid_copy (loc.gfid, oldinode->gfid);
+
+
+	if (IA_ISDIR (oldinode->ia_type))
+		ret = syncop_opendir (newsubvol, &loc, newfd);
+	else
+		ret = syncop_open (newsubvol, &loc,
+				   oldfd->flags & ~(O_TRUNC|O_EXCL|O_CREAT),
+				   newfd);
+	loc_wipe (&loc);
+
+	if (ret) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"syncop_open%s (%s) failed (%s) on graph %s (%d)",
+			IA_ISDIR (oldinode->ia_type) ? "dir" : "",
+			uuid_utoa_r (newinode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (newsubvol), newsubvol->graph->id);
+		goto out;
+	}
+
+	ret = glfs_migrate_fd_locks_safe (fs, oldsubvol, oldfd, newsubvol,
+					  newfd);
+
+	if (ret) {
+		gf_log (fs->volname, GF_LOG_WARNING,
+			"lock migration (%s) failed (%s) on graph %s (%d)",
+			uuid_utoa_r (newinode->gfid, uuid1),
+			strerror (errno),
+			graphid_str (newsubvol), newsubvol->graph->id);
+		goto out;
+	}
+
+        newfd->flags = oldfd->flags;
+	fd_bind (newfd);
+out:
+	if (newinode)
+		inode_unref (newinode);
+
+	if (ret) {
+		fd_unref (newfd);
+		newfd = NULL;
+	}
 
-	ret = glfs_resolve_at (fs, subvol, NULL, origpath, loc, iatt, 0);
+	return newfd;
+}
+
+
+fd_t *
+__glfs_migrate_fd (struct glfs *fs, xlator_t *newsubvol, struct glfs_fd *glfd)
+{
+	fd_t *oldfd = NULL;
+	fd_t *newfd = NULL;
+
+	oldfd = glfd->fd;
+
+	fs->migration_in_progress = 1;
+	pthread_mutex_unlock (&fs->mutex);
+	{
+		newfd = glfs_migrate_fd_safe (fs, newsubvol, oldfd);
+	}
+	pthread_mutex_lock (&fs->mutex);
+	fs->migration_in_progress = 0;
+	pthread_cond_broadcast (&fs->cond);
+
+	return newfd;
+}
+
+
+fd_t *
+__glfs_resolve_fd (struct glfs *fs, xlator_t *subvol, struct glfs_fd *glfd)
+{
+	fd_t *fd = NULL;
+
+	if (glfd->fd->inode->table->xl == subvol)
+		return fd_ref (glfd->fd);
+
+	fd = __glfs_migrate_fd (fs, subvol, glfd);
+	if (!fd)
+		return NULL;
+
+	if (subvol == fs->active_subvol) {
+		fd_unref (glfd->fd);
+		glfd->fd = fd_ref (fd);
+	}
+
+	return fd;
+}
+
+
+fd_t *
+glfs_resolve_fd (struct glfs *fs, xlator_t *subvol, struct glfs_fd *glfd)
+{
+	fd_t *fd = NULL;
+
+	glfs_lock (fs);
+	{
+		fd = __glfs_resolve_fd (fs, subvol, glfd);
+	}
+	glfs_unlock (fs);
+
+	return fd;
+}
+
+
+void
+__glfs_migrate_openfds (struct glfs *fs, xlator_t *subvol)
+{
+	struct glfs_fd *glfd = NULL;
+	fd_t *fd = NULL;
+
+	list_for_each_entry (glfd, &fs->openfds, openfds) {
+		if (uuid_is_null (glfd->fd->inode->gfid)) {
+			gf_log (fs->volname, GF_LOG_INFO,
+				"skipping openfd %p/%p in graph %s (%d)",
+				glfd, glfd->fd,	graphid_str(subvol),
+				subvol->graph->id);
+			/* create in progress, defer */
+			continue;
+		}
+
+		fd = __glfs_migrate_fd (fs, subvol, glfd);
+		if (fd) {
+			fd_unref (glfd->fd);
+			glfd->fd = fd;
+		}
+	}
+}
+
+
+xlator_t *
+__glfs_active_subvol (struct glfs *fs)
+{
+	xlator_t      *new_subvol = NULL;
+	int            ret = -1;
+	inode_t       *new_cwd = NULL;
+
+	if (!fs->next_subvol)
+		return fs->active_subvol;
+
+	new_subvol = fs->next_subvol;
+
+	ret = __glfs_first_lookup (fs, new_subvol);
+	if (ret) {
+		gf_log (fs->volname, GF_LOG_INFO,
+			"first lookup on graph %s (%d) failed (%s)",
+			graphid_str (new_subvol), new_subvol->graph->id,
+			strerror (errno));
+		return NULL;
+	}
+
+	if (fs->cwd) {
+		new_cwd = __glfs_refresh_inode (fs, new_subvol, fs->cwd);
+
+		if (!new_cwd) {
+			char buf1[64];
+			gf_log (fs->volname, GF_LOG_INFO,
+				"cwd refresh of %s graph %s (%d) failed (%s)",
+				uuid_utoa_r (fs->cwd->gfid, buf1),
+				graphid_str (new_subvol),
+				new_subvol->graph->id, strerror (errno));
+			return NULL;
+		}
+	}
+
+	__glfs_migrate_openfds (fs, new_subvol);
+
+	/* switching @active_subvol and @cwd
+	   should be atomic
+	*/
+	fs->old_subvol = fs->active_subvol;
+	fs->active_subvol = fs->next_subvol;
+	fs->next_subvol = NULL;
+
+	if (new_cwd) {
+		__glfs_cwd_set (fs, new_cwd);
+		inode_unref (new_cwd);
+	}
+
+	gf_log (fs->volname, GF_LOG_INFO, "switched to graph %s (%d)",
+		graphid_str (new_subvol), new_subvol->graph->id);
+
+	return new_subvol;
+}
+
+xlator_t *
+glfs_active_subvol (struct glfs *fs)
+{
+	xlator_t      *subvol = NULL;
+	xlator_t      *old_subvol = NULL;
+
+	glfs_lock (fs);
+	{
+		subvol = __glfs_active_subvol (fs);
+
+		if (subvol)
+			subvol->winds++;
+
+		if (fs->old_subvol) {
+			old_subvol = fs->old_subvol;
+			fs->old_subvol = NULL;
+			old_subvol->switched = 1;
+		}
+	}
+	glfs_unlock (fs);
+
+	if (old_subvol)
+		glfs_subvol_done (fs, old_subvol);
+
+	return subvol;
+}
+
+
+void
+glfs_subvol_done (struct glfs *fs, xlator_t *subvol)
+{
+	int ref = 0;
+	xlator_t *active_subvol = NULL;
+
+	if (!subvol)
+		return;
+
+	glfs_lock (fs);
+	{
+		ref = (--subvol->winds);
+		active_subvol = fs->active_subvol;
+	}
+	glfs_unlock (fs);
+
+	if (ref == 0) {
+		assert (subvol != active_subvol);
+		xlator_notify (subvol, GF_EVENT_PARENT_DOWN, subvol, NULL);
+	}
+}
+
+
+int
+__glfs_cwd_set (struct glfs *fs, inode_t *inode)
+{
+	if (inode->table->xl != fs->active_subvol) {
+		inode = __glfs_refresh_inode (fs, fs->active_subvol, inode);
+		if (!inode)
+			return -1;
+	} else {
+		inode_ref (inode);
+	}
+
+	if (fs->cwd)
+		inode_unref (fs->cwd);
+
+	fs->cwd = inode;
+
+	return 0;
+}
+
+
+int
+glfs_cwd_set (struct glfs *fs, inode_t *inode)
+{
+	int ret = 0;
+
+	glfs_lock (fs);
+	{
+		ret = __glfs_cwd_set (fs, inode);
+	}
+	glfs_unlock (fs);
 
 	return ret;
 }
 
+
+inode_t *
+__glfs_cwd_get (struct glfs *fs)
+{
+	inode_t *cwd = NULL;
+
+	if (!fs->cwd)
+		return NULL;
+
+	if (fs->cwd->table->xl == fs->active_subvol) {
+		cwd = inode_ref (fs->cwd);
+		return cwd;
+	}
+
+	cwd = __glfs_refresh_inode (fs, fs->active_subvol, fs->cwd);
+
+	return cwd;
+}
+
+inode_t *
+glfs_cwd_get (struct glfs *fs)
+{
+	inode_t *cwd = NULL;
+
+	glfs_lock (fs);
+	{
+		cwd = __glfs_cwd_get (fs);
+	}
+	glfs_unlock (fs);
+
+	return cwd;
+}
+
+inode_t *
+__glfs_resolve_inode (struct glfs *fs, xlator_t *subvol,
+		    struct glfs_object *object)
+{
+	inode_t *inode = NULL;
+
+	if (object->inode->table->xl == subvol)
+		return inode_ref (object->inode);
+
+	inode = __glfs_refresh_inode (fs, fs->active_subvol,
+					object->inode);
+	if (!inode)
+		return NULL;
+
+	if (subvol == fs->active_subvol) {
+		inode_unref (object->inode);
+		object->inode = inode_ref (inode);
+	}
+
+	return inode;
+}
+
+inode_t *
+glfs_resolve_inode (struct glfs *fs, xlator_t *subvol,
+		    struct glfs_object *object)
+{
+	inode_t *inode = NULL;
+
+	glfs_lock (fs);
+	{
+		inode = __glfs_resolve_inode(fs, subvol, object);
+	}
+	glfs_unlock (fs);
+
+	return inode;
+}
+
+int
+glfs_create_object (loc_t *loc, struct glfs_object **retobject)
+{
+	struct glfs_object *object = NULL;
+
+	object = GF_CALLOC (1, sizeof(struct glfs_object),
+			    glfs_mt_glfs_object_t);
+	if (object == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	object->inode = loc->inode;
+	uuid_copy (object->gfid, object->inode->gfid);
+
+	/* we hold the reference */
+	loc->inode = NULL;
+
+	*retobject = object;
+
+	return 0;
+}
diff --git a/api/src/glfs.c b/api/src/glfs.c
index f0bdc86f0..29ed47c0c 100644
--- a/api/src/glfs.c
+++ b/api/src/glfs.c
@@ -11,17 +11,15 @@
 
 /*
   TODO:
+  - merge locks in glfs_posix_lock for lock self-healing
   - set proper pid/lk_owner to call frames (currently buried in syncop)
   - fix logging.c/h to store logfp and loglevel in glusterfs_ctx_t and
     reach it via THIS.
-  - fd migration on graph switch.
   - update syncop functions to accept/return xdata. ???
   - protocol/client to reconnect immediately after portmap disconnect.
   - handle SEEK_END failure in _lseek()
   - handle umask (per filesystem?)
-  - implement glfs_set_xlator_option(), like --xlator-option
   - make itables LRU based
-  - implement glfs_fini()
   - 0-copy for readv/writev
   - reconcile the open/creat mess
 */
@@ -51,6 +49,8 @@
 
 #include "glfs.h"
 #include "glfs-internal.h"
+#include "hashfn.h"
+#include "rpc-clnt.h"
 
 
 static gf_boolean_t
@@ -66,7 +66,7 @@ glusterfs_ctx_defaults_init (glusterfs_ctx_t *ctx)
 	call_pool_t   *pool = NULL;
 	int	       ret = -1;
 
-	xlator_mem_acct_init (THIS, glfs_mt_end);
+	xlator_mem_acct_init (THIS, glfs_mt_end + 1);
 
 	ctx->process_uuid = generate_glusterfs_ctx_id ();
 	if (!ctx->process_uuid) {
@@ -85,7 +85,7 @@ glusterfs_ctx_defaults_init (glusterfs_ctx_t *ctx)
 		goto err;
 	}
 
-	ctx->env = syncenv_new (0);
+	ctx->env = syncenv_new (0, 0, 0);
 	if (!ctx->env) {
 		goto err;
 	}
@@ -277,69 +277,117 @@ out:
 ///////////////////////////////////////////////////////////////////////////////
 
 
-struct glfs *
-glfs_from_glfd (struct glfs_fd *glfd)
+int
+glfs_set_xlator_option (struct glfs *fs, const char *xlator, const char *key,
+			const char *value)
 {
-	return 	((xlator_t *)glfd->fd->inode->table->xl->ctx->master)->private;
+	xlator_cmdline_option_t *option = NULL;
+
+	option = GF_CALLOC (1, sizeof (*option),
+			    glfs_mt_xlator_cmdline_option_t);
+	if (!option)
+		goto enomem;
+
+	INIT_LIST_HEAD (&option->cmd_args);
+
+	option->volume = gf_strdup (xlator);
+	if (!option->volume)
+		goto enomem;
+	option->key = gf_strdup (key);
+	if (!option->key)
+		goto enomem;
+	option->value = gf_strdup (value);
+	if (!option->value)
+		goto enomem;
+
+	list_add (&option->cmd_args, &fs->ctx->cmd_args.xlator_options);
+
+	return 0;
+enomem:
+	errno = ENOMEM;
+
+	if (!option)
+		return -1;
+
+	GF_FREE (option->volume);
+	GF_FREE (option->key);
+	GF_FREE (option->value);
+	GF_FREE (option);
+
+	return -1;
 }
 
+int glfs_setfsuid (uid_t fsuid)
+{
+	return syncopctx_setfsuid (&fsuid);
+}
 
-void
-glfs_fd_destroy (struct glfs_fd *glfd)
+int glfs_setfsgid (gid_t fsgid)
 {
-	if (!glfd)
-		return;
-	if (glfd->fd)
-		fd_unref (glfd->fd);
-	GF_FREE (glfd);
+	return syncopctx_setfsgid (&fsgid);
 }
 
+int glfs_setfsgroups (size_t size, const gid_t *list)
+{
+	return syncopctx_setfsgroups(size, list);
+}
 
-xlator_t *
-glfs_fd_subvol (struct glfs_fd *glfd)
+struct glfs *
+glfs_from_glfd (struct glfs_fd *glfd)
 {
-	xlator_t    *subvol = NULL;
+	return glfd->fs;
+}
+
+
+struct glfs_fd *
+glfs_fd_new (struct glfs *fs)
+{
+	struct glfs_fd  *glfd = NULL;
 
+	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
 	if (!glfd)
 		return NULL;
 
-	subvol = glfd->fd->inode->table->xl;
+	glfd->fs = fs;
 
-	return subvol;
+	INIT_LIST_HEAD (&glfd->openfds);
+
+	return glfd;
 }
 
 
-xlator_t *
-glfs_active_subvol (struct glfs *fs)
+void
+glfs_fd_bind (struct glfs_fd *glfd)
 {
-	xlator_t      *subvol = NULL;
-	inode_table_t *itable = NULL;
+	struct glfs *fs = NULL;
 
-	pthread_mutex_lock (&fs->mutex);
-	{
-		while (!fs->init)
-			pthread_cond_wait (&fs->cond, &fs->mutex);
+	fs = glfd->fs;
 
-		subvol = fs->active_subvol;
+	glfs_lock (fs);
+	{
+		list_add_tail (&glfd->openfds, &fs->openfds);
 	}
-	pthread_mutex_unlock (&fs->mutex);
+	glfs_unlock (fs);
+}
 
-	if (!subvol)
-		return NULL;
+void
+glfs_fd_destroy (struct glfs_fd *glfd)
+{
+	if (!glfd)
+		return;
 
-	if (!subvol->itable) {
-		itable = inode_table_new (0, subvol);
-		if (!itable) {
-			errno = ENOMEM;
-			return NULL;
-		}
+	glfs_lock (glfd->fs);
+	{
+		list_del_init (&glfd->openfds);
+	}
+	glfs_unlock (glfd->fs);
 
-		subvol->itable = itable;
+	if (glfd->fd)
+		fd_unref (glfd->fd);
 
-		glfs_first_lookup (subvol);
-	}
+	GF_FREE (glfd->readdirbuf);
 
-	return subvol;
+	GF_FREE (glfd);
 }
 
 
@@ -368,7 +416,9 @@ glfs_new (const char *volname)
 		return NULL;
 	}
 
+#ifdef DEBUG
         gf_mem_acct_enable_set (ctx);
+#endif
 
 	/* first globals init, for gf_mem_acct_enable_set () */
 	ret = glusterfs_globals_init (ctx);
@@ -396,6 +446,8 @@ glfs_new (const char *volname)
 	pthread_mutex_init (&fs->mutex, NULL);
 	pthread_cond_init (&fs->cond, NULL);
 
+	INIT_LIST_HEAD (&fs->openfds);
+
 	return fs;
 }
 
@@ -439,14 +491,26 @@ glfs_set_volfile_server (struct glfs *fs, const char *transport,
 int
 glfs_set_logging (struct glfs *fs, const char *logfile, int loglevel)
 {
-	int  ret = -1;
+	int  ret = 0;
+        char *tmplog = NULL;
 
-	ret = gf_log_init (fs->ctx, logfile);
-	if (ret)
-		return ret;
+        if (!logfile) {
+                ret = gf_set_log_file_path (&fs->ctx->cmd_args);
+                if (ret)
+                        goto out;
+                tmplog = fs->ctx->cmd_args.log_file;
+        } else {
+                tmplog = (char *)logfile;
+        }
 
-	gf_log_set_loglevel (loglevel);
+        ret = gf_log_init (fs->ctx, tmplog, NULL);
+        if (ret)
+                goto out;
 
+	if (loglevel >= 0)
+		gf_log_set_loglevel (loglevel);
+
+out:
 	return ret;
 }
 
@@ -456,7 +520,8 @@ glfs_init_wait (struct glfs *fs)
 {
 	int   ret = -1;
 
-	pthread_mutex_lock (&fs->mutex);
+	/* Always a top-down call, use glfs_lock() */
+	glfs_lock (fs);
 	{
 		while (!fs->init)
 			pthread_cond_wait (&fs->cond,
@@ -464,7 +529,7 @@ glfs_init_wait (struct glfs *fs)
 		ret = fs->ret;
 		errno = fs->err;
 	}
-	pthread_mutex_unlock (&fs->mutex);
+	glfs_unlock (fs);
 
 	return ret;
 }
@@ -473,20 +538,32 @@ glfs_init_wait (struct glfs *fs)
 void
 glfs_init_done (struct glfs *fs, int ret)
 {
-	if (fs->init_cbk) {
-		fs->init_cbk (fs, ret);
-		return;
+	glfs_init_cbk init_cbk;
+
+	if (!fs) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"fs is NULL");
+		goto out;
 	}
 
+	init_cbk = fs->init_cbk;
+
+	/* Always a bottom-up call, use mutex_lock() */
 	pthread_mutex_lock (&fs->mutex);
 	{
 		fs->init = 1;
 		fs->ret = ret;
 		fs->err = errno;
 
-		pthread_cond_broadcast (&fs->cond);
+		if (!init_cbk)
+			pthread_cond_broadcast (&fs->cond);
 	}
 	pthread_mutex_unlock (&fs->mutex);
+
+	if (init_cbk)
+		init_cbk (fs, ret);
+out:
+	return;
 }
 
 
@@ -499,7 +576,7 @@ glfs_init_common (struct glfs *fs)
 	if (ret)
 		return ret;
 
-	ret = pthread_create (&fs->poller, NULL, glfs_poller, fs);
+	ret = gf_thread_create (&fs->poller, NULL, glfs_poller, fs);
 	if (ret)
 		return ret;
 
@@ -507,6 +584,7 @@ glfs_init_common (struct glfs *fs)
 	if (ret)
 		return ret;
 
+	fs->dev_id = gf_dm_hashfn (fs->volname, strlen (fs->volname));
 	return ret;
 }
 
@@ -542,7 +620,54 @@ glfs_init (struct glfs *fs)
 int
 glfs_fini (struct glfs *fs)
 {
-	int  ret = -1;
-
-	return ret;
+        int             ret = -1;
+        int             countdown = 100;
+        xlator_t        *subvol = NULL;
+        glusterfs_ctx_t *ctx = NULL;
+        call_pool_t     *call_pool = NULL;
+
+        ctx = fs->ctx;
+
+        if (ctx->mgmt) {
+                rpc_clnt_disable (ctx->mgmt);
+                ctx->mgmt = NULL;
+        }
+
+        __glfs_entry_fs (fs);
+
+        call_pool = fs->ctx->pool;
+
+        while (countdown--) {
+                /* give some time for background frames to finish */
+                if (!call_pool->cnt)
+                        break;
+                usleep (100000);
+        }
+        /* leaked frames may exist, we ignore */
+
+        /*We deem glfs_fini as successful if there are no pending frames in the call
+         *pool*/
+        ret = (call_pool->cnt == 0)? 0: -1;
+
+        subvol = glfs_active_subvol (fs);
+        if (subvol) {
+                /* PARENT_DOWN within glfs_subvol_done() is issued only
+                   on graph switch (new graph should activiate and
+                   decrement the extra @winds count taken in glfs_graph_setup()
+
+                   Since we are explicitly destroying, PARENT_DOWN is necessary
+                */
+                xlator_notify (subvol, GF_EVENT_PARENT_DOWN, subvol, 0);
+                /* TBD: wait for CHILD_DOWN before exiting, in case of
+                   asynchronous cleanup like graceful socket disconnection
+                   in the future.
+                */
+        }
+
+        glfs_subvol_done (fs, subvol);
+
+        if (ctx->log.logfile)
+                fclose (ctx->log.logfile);
+
+        return ret;
 }
diff --git a/api/src/glfs.h b/api/src/glfs.h
index e19c1cd25..18fda496e 100644
--- a/api/src/glfs.h
+++ b/api/src/glfs.h
@@ -176,7 +176,9 @@ int glfs_set_volfile_server (glfs_t *fs, const char *transport,
   @fs: The 'virtual mount' object to be configured with the logging parameters.
 
   @logfile: The logfile to be used for logging. Will be created if it does not
-            already exist (provided system permissions allow.)
+            already exist (provided system permissions allow). If NULL, a new
+            logfile will be created in default log directory associated with
+            the glusterfs installation.
 
   @loglevel: Numerical value specifying the degree of verbosity. Higher the
              value, more verbose the logging.
@@ -218,6 +220,36 @@ int glfs_set_logging (glfs_t *fs, const char *logfile, int loglevel);
 int glfs_init (glfs_t *fs);
 
 
+/*
+  SYNOPSIS
+
+  glfs_fini: Cleanup and destroy the 'virtual mount'
+
+  DESCRIPTION
+
+  This function attempts to gracefully destroy glfs_t object. An attempt is
+  made to wait for all background processing to complete before returning.
+
+  glfs_fini() must be called after all operations on glfs_t is finished.
+
+  IMPORTANT
+
+  IT IS NECESSARY TO CALL glfs_fini() ON ALL THE INITIALIZED glfs_t
+  OBJECTS BEFORE TERMINATING THE PROGRAM. THERE MAY BE CACHED AND
+  UNWRITTEN / INCOMPLETE OPERATIONS STILL IN PROGRESS EVEN THOUGH THE
+  API CALLS HAVE RETURNED. glfs_fini() WILL WAIT FOR BACKGROUND OPERATIONS
+  TO COMPLETE BEFORE RETURNING, THEREBY MAKING IT SAFE FOR THE PROGRAM TO
+  EXIT.
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be destroyed.
+
+  RETURN VALUES
+
+   0 : Success.
+*/
+
 int glfs_fini (glfs_t *fs);
 
 /*
@@ -239,6 +271,32 @@ int glfs_fini (glfs_t *fs);
 struct glfs_fd;
 typedef struct glfs_fd glfs_fd_t;
 
+/*
+ * PER THREAD IDENTITY MODIFIERS
+ *
+ * The following operations enable to set a per thread identity context
+ * for the glfs APIs to perform operations as. The calls here are kept as close
+ * to POSIX equivalents as possible.
+ *
+ * NOTES:
+ *
+ *  - setgroups is a per thread setting, hence this is named as fsgroups to be
+ *    close in naming to the fs(u/g)id APIs
+ *  - Typical mode of operation is to set the IDs as required, with the
+ *    supplementary groups being optionally set, make the glfs call and post the
+ *    glfs operation set them back to eu/gid or uid/gid as appropriate to the
+ *    caller
+ *  - The groups once set, need to be unset by setting the size to 0 (in which
+ *    case the list argument is a do not care)
+ *  - Once a process for a thread of operation choses to set the IDs, all glfs
+ *    calls made from that thread would default to the IDs set for the thread.
+ *    As a result use these APIs with care and ensure that the set IDs are
+ *    reverted to global process defaults as required.
+ *
+ */
+int glfs_setfsuid (uid_t fsuid);
+int glfs_setfsgid (gid_t fsgid);
+int glfs_setfsgroups (size_t size, const gid_t *list);
 
 /*
   SYNOPSIS
@@ -301,6 +359,32 @@ int glfs_close (glfs_fd_t *fd);
 
 glfs_t *glfs_from_glfd (glfs_fd_t *fd);
 
+int glfs_set_xlator_option (glfs_t *fs, const char *xlator, const char *key,
+			    const char *value);
+
+/*
+
+  glfs_io_cbk
+
+  The following is the function type definition of the callback
+  function pointer which has to be provided by the caller to the
+  *_async() versions of the IO calls.
+
+  The callback function is called on completion of the requested
+  IO, and the appropriate return value is returned in @ret.
+
+  In case of an error in completing the IO, @ret will be -1 and
+  @errno will be set with the appropriate error.
+
+  @ret will be same as the return value of the non _async() variant
+  of the particular call
+
+  @data is the same context pointer provided by the caller at the
+  time of issuing the async IO call. This can be used by the
+  caller to differentiate different instances of the async requests
+  in a common callback function.
+*/
+
 typedef void (*glfs_io_cbk) (glfs_fd_t *fd, ssize_t ret, void *data);
 
 // glfs_{read,write}[_async]
@@ -384,9 +468,31 @@ int glfs_link (glfs_t *fs, const char *oldpath, const char *newpath);
 
 glfs_fd_t *glfs_opendir (glfs_t *fs, const char *path);
 
+/*
+ * @glfs_readdir_r and @glfs_readdirplus_r ARE thread safe AND re-entrant,
+ * but the interface has ambiguity about the size of @dirent to be allocated
+ * before calling the APIs. 512 byte buffer (for @dirent) is sufficient for
+ * all known systems which are tested againt glusterfs/gfapi, but may be
+ * insufficient in the future.
+ */
+
 int glfs_readdir_r (glfs_fd_t *fd, struct dirent *dirent,
 		    struct dirent **result);
 
+int glfs_readdirplus_r (glfs_fd_t *fd, struct stat *stat, struct dirent *dirent,
+			struct dirent **result);
+
+/*
+ * @glfs_readdir and @glfs_readdirplus are NEITHER thread safe NOR re-entrant
+ * when called on the same directory handle. However they ARE thread safe
+ * AND re-entrant when called on different directory handles (which may be
+ * referring to the same directory too.)
+ */
+
+struct dirent *glfs_readdir (glfs_fd_t *fd);
+
+struct dirent *glfs_readdirplus (glfs_fd_t *fd, struct stat *stat);
+
 long glfs_telldir (glfs_fd_t *fd);
 
 void glfs_seekdir (glfs_fd_t *fd, long offset);
@@ -442,6 +548,34 @@ int glfs_lremovexattr (glfs_t *fs, const char *path, const char *name);
 
 int glfs_fremovexattr (glfs_fd_t *fd, const char *name);
 
+int glfs_fallocate(glfs_fd_t *fd, int keep_size, off_t offset, size_t len);
+
+int glfs_discard(glfs_fd_t *fd, off_t offset, size_t len);
+
+
+int glfs_discard_async (glfs_fd_t *fd, off_t length, size_t lent,
+			glfs_io_cbk fn, void *data);
+
+int glfs_zerofill(glfs_fd_t *fd, off_t offset, size_t len);
+
+int glfs_zerofill_async (glfs_fd_t *fd, off_t length, size_t len,
+                        glfs_io_cbk fn, void *data);
+
+char *glfs_getcwd (glfs_t *fs, char *buf, size_t size);
+
+int glfs_chdir (glfs_t *fs, const char *path);
+
+int glfs_fchdir (glfs_fd_t *fd);
+
+char *glfs_realpath (glfs_t *fs, const char *path, char *resolved_path);
+
+/*
+ * @cmd and @flock are as specified in man fcntl(2).
+ */
+int glfs_posix_lock (glfs_fd_t *fd, int cmd, struct flock *flock);
+
+glfs_fd_t *glfs_dup (glfs_fd_t *fd);
+
 __END_DECLS
 
 #endif /* !_GLFS_H */
diff --git a/argp-standalone/configure.ac b/argp-standalone/configure.ac
index 65ebc4518..2ecd2a801 100644
--- a/argp-standalone/configure.ac
+++ b/argp-standalone/configure.ac
@@ -8,7 +8,7 @@ AC_CONFIG_SRCDIR([argp-ba.c])
 AC_CONFIG_AUX_DIR([.])
 
 AM_INIT_AUTOMAKE
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS(config.h)
 
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES(yes)])
 
@@ -22,7 +22,7 @@ AC_GNU_SOURCE
 AC_PROG_CC
 AC_PROG_MAKE_SET
 AC_PROG_RANLIB
-AM_PROG_CC_STDC
+AC_PROG_CC
 
 if test "x$am_cv_prog_cc_stdc" = xno ; then
   AC_ERROR([the C compiler doesn't handle ANSI-C])
diff --git a/autogen.sh b/autogen.sh
index ca69d4624..f937e6be0 100755
--- a/autogen.sh
+++ b/autogen.sh
@@ -1,8 +1,105 @@
 #!/bin/sh
 
-aclocal -I ./contrib/aclocal
-autoheader
-(libtoolize --automake --copy --force || glibtoolize --automake --copy --force)
-autoconf
-automake --add-missing --copy --foreign
+echo
+echo ... GlusterFS autogen ...
+echo
+
+## Check all dependencies are present
+MISSING=""
+
+# Check for aclocal
+env aclocal --version > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+  ACLOCAL=aclocal
+else
+  MISSING="$MISSING aclocal"
+fi
+
+# Check for autoconf
+env autoconf --version > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+  AUTOCONF=autoconf
+else
+  MISSING="$MISSING autoconf"
+fi
+
+# Check for autoheader
+env autoheader --version > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+  AUTOHEADER=autoheader
+else
+  MISSING="$MISSING autoheader"
+fi
+
+# Check for automake
+env automake --version > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+  AUTOMAKE=automake
+else
+  MISSING="$MISSING automake"
+fi
+
+# Check for libtoolize or glibtoolize
+env libtoolize --version > /dev/null 2>&1
+if [ $? -eq 0 ]; then
+  # libtoolize was found, so use it
+  TOOL=libtoolize
+else
+  # libtoolize wasn't found, so check for glibtoolize
+  env glibtoolize --version > /dev/null 2>&1
+  if [ $? -eq 0 ]; then
+    TOOL=glibtoolize
+  else
+    MISSING="$MISSING libtoolize/glibtoolize"
+  fi
+fi
+
+# Check for tar
+env tar --version > /dev/null 2>&1
+if [ $? -ne 0 ]; then
+  MISSING="$MISSING tar"
+fi
+
+## If dependencies are missing, warn the user and abort
+if [ "x$MISSING" != "x" ]; then
+  echo "Aborting."
+  echo
+  echo "The following build tools are missing:"
+  echo
+  for pkg in $MISSING; do
+    echo "  * $pkg"
+  done
+  echo
+  echo "Please install them and try again."
+  echo
+  exit 1
+fi
+
+## generate gf-error-codes.h from error-codes.json
+echo "Generate gf-error-codes.h ..."
+if ./gen-headers.py; then
+    if ! mv -fv gf-error-codes.h libglusterfs/src/gf-error-codes.h; then
+	exit 1
+    fi
+else
+    exit 1
+fi
+
+## Do the autogeneration
+echo Running ${ACLOCAL}...
+$ACLOCAL -I ./contrib/aclocal
+echo Running ${AUTOHEADER}...
+$AUTOHEADER
+echo Running ${TOOL}...
+$TOOL --automake --copy --force
+echo Running ${AUTOCONF}...
+$AUTOCONF
+echo Running ${AUTOMAKE}...
+$AUTOMAKE --add-missing --copy --foreign
+
+# Run autogen in the argp-standalone sub-directory
 cd argp-standalone;./autogen.sh
+
+# Instruct user on next steps
+echo
+echo "Please proceed with configuring, compiling, and installing."
diff --git a/cli/src/Makefile.am b/cli/src/Makefile.am
index 7054f1120..216d1bb55 100644
--- a/cli/src/Makefile.am
+++ b/cli/src/Makefile.am
@@ -2,15 +2,12 @@ sbin_PROGRAMS = gluster
 
 gluster_SOURCES = cli.c registry.c input.c cli-cmd.c cli-rl.c \
 	 cli-cmd-volume.c cli-cmd-peer.c cli-rpc-ops.c cli-cmd-parser.c\
-	 cli-cmd-system.c cli-cmd-misc.c cli-xml-output.c
-if ENABLE_BD_XLATOR
-gluster_SOURCES += cli-cmd-volume-bdevice.c
-endif
+	 cli-cmd-system.c cli-cmd-misc.c cli-xml-output.c cli-cmd-snapshot.c
 
 gluster_LDADD = $(top_builddir)/libglusterfs/src/libglusterfs.la $(GF_LDADD)\
 		$(RLLIBS) $(top_builddir)/rpc/xdr/src/libgfxdr.la \
 		$(top_builddir)/rpc/rpc-lib/src/libgfrpc.la \
-		$(GF_GLUSTERFS_LIBS) $(LIBXML2_LIBS)
+		$(GF_GLUSTERFS_LIBS) $(XML_LIBS)
 
 gluster_LDFLAGS = $(GF_LDFLAGS)
 noinst_HEADERS = cli.h cli-mem-types.h cli-cmd.h
@@ -22,7 +19,7 @@ AM_CPPFLAGS = $(GF_CPPFLAGS) \
 	-DCONFDIR=\"$(sysconfdir)/glusterfs\" \
 	-DGSYNCD_PREFIX=\"$(libexecdir)/glusterfs\"\
 	-DSYNCDAEMON_COMPILE=$(SYNCDAEMON_COMPILE) -DSBIN_DIR=\"$(sbindir)\"\
-	$(LIBXML2_CFLAGS)
+	$(XML_CPPFLAGS)
 
 AM_CFLAGS = -Wall $(GF_GLUSTERFS_CFLAGS)
 
diff --git a/cli/src/cli-cmd-misc.c b/cli/src/cli-cmd-misc.c
index 5f3a77ca6..566d7c978 100644
--- a/cli/src/cli-cmd-misc.c
+++ b/cli/src/cli-cmd-misc.c
@@ -32,6 +32,7 @@ extern struct cli_cmd cli_probe_cmds[];
 extern struct cli_cmd cli_log_cmds[];
 extern struct cli_cmd cli_system_cmds[];
 extern struct cli_cmd cli_bd_cmds[];
+extern struct cli_cmd snapshot_cmds[];
 struct cli_cmd cli_misc_cmds[];
 
 int
@@ -46,10 +47,7 @@ cli_cmd_display_help (struct cli_state *state, struct cli_cmd_word *in_word,
                       const char **words, int wordcount)
 {
         struct cli_cmd        *cmd[] = {volume_cmds, cli_probe_cmds,
-                                       cli_misc_cmds,
-#ifdef HAVE_BD_XLATOR
-                                       cli_bd_cmds,
-#endif
+                                       cli_misc_cmds, snapshot_cmds,
                                        NULL};
         struct cli_cmd        *cmd_ind = NULL;
         int                   i = 0;
diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index ae754b97c..5ab208b8f 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -1,5 +1,5 @@
 /*
-   Copyright (c) 2010-2012 Red Hat, Inc. <http://www.redhat.com>
+   Copyright (c) 2010-2013 Red Hat, Inc. <http://www.redhat.com>
    This file is part of GlusterFS.
 
    This file is licensed to you under your choice of the GNU Lesser
@@ -26,6 +26,38 @@
 #include "protocol-common.h"
 #include "cli1-xdr.h"
 
+#define MAX_SNAP_DESCRIPTION_LEN 1024
+
+struct snap_config_opt_vals_ snap_confopt_vals[] = {
+        {.op_name        = "snap-max-hard-limit",
+         .question       = "Changing snapshot-max-hard-limit "
+                           "will lead to deletion of snapshots "
+                           "if they exceed the new limit.\n"
+                           "Do you want to continue?"
+        },
+        {.op_name        = "snap-max-soft-limit",
+         .question       = "Changing snapshot-max-soft-limit "
+                           "will lead to deletion of snapshots "
+                           "if they exceed the new limit.\n"
+                           "Do you want to continue?"
+        },
+        {.op_name        = "both",
+        .question        = "Changing snapshot-max-hard-limit & "
+                           "snapshot-max-soft-limit will lead to "
+                           "deletion of snapshots if they exceed "
+                           "the new limit.\nDo you want to continue?"
+        },
+        {.op_name        = NULL,
+        }
+};
+
+enum cli_snap_config_set_types {
+        GF_SNAP_CONFIG_SET_HARD = 0,
+        GF_SNAP_CONFIG_SET_SOFT = 1,
+        GF_SNAP_CONFIG_SET_BOTH = 2,
+};
+typedef enum cli_snap_config_set_types cli_snap_config_set_types;
+
 static const char *
 id_sel (void *wcon)
 {
@@ -159,21 +191,19 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
         int32_t index = 0;
         char    *bricks = NULL;
         int32_t brick_count = 0;
-        char    *opwords[] = { "replica", "stripe", "transport",
-#ifdef HAVE_BD_XLATOR
-                                "device",
-#endif
-                                NULL };
+        char    *opwords[] = { "replica", "stripe", "transport", NULL };
 
         char    *invalid_volnames[] = {"volume", "type", "subvolumes", "option",
-                                      "end-volume", "all", NULL};
+                                       "end-volume", "all", "volume_not_in_ring",
+                                       "description", "force",
+                                       "snap-max-hard-limit",
+                                       "snap-max-soft-limit", NULL};
         char    *w = NULL;
         int      op_count = 0;
         int32_t  replica_count = 1;
         int32_t  stripe_count = 1;
-#ifdef HAVE_BD_XLATOR
-        char     *dev_type = NULL;
-#endif
+        gf_boolean_t is_force = _gf_false;
+        int wc = wordcount;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -308,26 +338,7 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
                                 goto out;
                         }
                         index += 2;
-                }
-#ifdef HAVE_BD_XLATOR
-                else if ((strcmp (w, "device")) == 0) {
-                        if (dev_type) {
-                                cli_err ("'device' option given more"
-                                         " than one time");
-                                goto out;
-                        }
-                        if ((strcasecmp (words[index+1], "vg") == 0)) {
-                                dev_type = gf_strdup ("vg");
-                        } else {
-                                gf_log ("", GF_LOG_ERROR, "incorrect"
-                                        " device type specified");
-                                ret = -1;
-                                goto out;
-                        }
-                        index += 2;
-                }
-#endif
-                else {
+                }              else {
                         GF_ASSERT (!"opword mismatch");
                         ret = -1;
                         goto out;
@@ -350,7 +361,12 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
 
         brick_index = index;
 
-        ret = cli_cmd_bricks_parse (words, wordcount, brick_index, &bricks,
+        if (strcmp (words[wordcount - 1], "force") == 0) {
+                is_force = _gf_true;
+                wc = wordcount - 1;
+        }
+
+        ret = cli_cmd_bricks_parse (words, wc, brick_index, &bricks,
                                     &brick_count);
         if (ret)
                 goto out;
@@ -363,19 +379,6 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
                 goto out;
         }
 
-        /* BD xlator does not support multiple bricks */
-#ifdef HAVE_BD_XLATOR
-        if (brick_count > 1 && dev_type) {
-                cli_err ("Block Device backend volume does not support multiple"
-                         " bricks");
-                gf_log ("", GF_LOG_ERROR,
-                         "Block Device backend volume does not support multiple"
-                        " bricks");
-                ret = -1;
-                goto out;
-        }
-#endif
-
         if (brick_count % sub_count) {
                 if (type == GF_CLUSTER_TYPE_STRIPE)
                         cli_err ("number of bricks is not a multiple of "
@@ -409,18 +412,14 @@ cli_cmd_volume_create_parse (const char **words, int wordcount, dict_t **options
         if (ret)
                 goto out;
 
-#ifdef HAVE_BD_XLATOR
-        if (dev_type) {
-                ret = dict_set_dynstr (dict, "device", dev_type);
-                if (ret)
-                        goto out;
-        }
-#endif
-
         ret = dict_set_int32 (dict, "count", brick_count);
         if (ret)
                 goto out;
 
+        ret = dict_set_int32 (dict, "force", is_force);
+        if (ret)
+                goto out;
+
         *options = dict;
 
 out:
@@ -700,7 +699,7 @@ cli_is_key_spl (char *key)
 
 #define GLUSTERD_DEFAULT_WORKDIR "/var/lib/glusterd"
 static int
-cli_add_key_group (dict_t *dict, char *key, char *value)
+cli_add_key_group (dict_t *dict, char *key, char *value, char **op_errstr)
 {
         int             ret = -1;
         int             opt_count = 0;
@@ -714,6 +713,7 @@ cli_add_key_group (dict_t *dict, char *key, char *value)
         char            *tagpath = NULL;
         char            *buf = NULL;
         char            line[PATH_MAX + 256] = {0,};
+        char            errstr[2048] = "";
         FILE            *fp = NULL;
 
         ret = gf_asprintf (&tagpath, "%s/groups/%s",
@@ -726,6 +726,10 @@ cli_add_key_group (dict_t *dict, char *key, char *value)
         fp = fopen (tagpath, "r");
         if (!fp) {
                 ret = -1;
+                snprintf(errstr, sizeof(errstr), "Unable to open file '%s'."
+                         " Error: %s", tagpath, strerror (errno));
+                if (op_errstr)
+                        *op_errstr = gf_strdup(errstr);
                 goto out;
         }
 
@@ -738,6 +742,10 @@ cli_add_key_group (dict_t *dict, char *key, char *value)
                 tok_val = strtok_r (NULL, "=", &saveptr);
                 if (!tok_key || !tok_val) {
                         ret = -1;
+                        snprintf(errstr, sizeof(errstr), "'%s' file format "
+                                 "not valid.", tagpath);
+                        if (op_errstr)
+                                *op_errstr = gf_strdup(errstr);
                         goto out;
                 }
 
@@ -759,6 +767,10 @@ cli_add_key_group (dict_t *dict, char *key, char *value)
 
         if (!opt_count) {
                 ret = -1;
+                snprintf(errstr, sizeof(errstr), "'%s' file format "
+                         "not valid.", tagpath);
+                if (op_errstr)
+                        *op_errstr = gf_strdup(errstr);
                 goto out;
         }
         ret = dict_set_int32 (dict, "count", opt_count);
@@ -779,7 +791,8 @@ out:
 #undef GLUSTERD_DEFAULT_WORKDIR
 
 int32_t
-cli_cmd_volume_set_parse (const char **words, int wordcount, dict_t **options)
+cli_cmd_volume_set_parse (const char **words, int wordcount, dict_t **options,
+                          char **op_errstr)
 {
         dict_t                  *dict = NULL;
         char                    *volname = NULL;
@@ -832,7 +845,12 @@ cli_cmd_volume_set_parse (const char **words, int wordcount, dict_t **options)
                 if (ret == -1)
                         goto out;
 
-                ret = cli_add_key_group (dict, key, value);
+                if (strlen (value) == 0) {
+                        ret = -1;
+                        goto out;
+                }
+
+                ret = cli_add_key_group (dict, key, value, op_errstr);
                 if (ret == 0)
                         *options = dict;
                 goto out;
@@ -854,6 +872,11 @@ cli_cmd_volume_set_parse (const char **words, int wordcount, dict_t **options)
                 if (ret == -1)
                         goto out;
 
+                if (strlen (value) == 0) {
+                        ret = -1;
+                        goto out;
+                }
+
                 if (cli_is_key_spl (key)) {
                         ret = -1;
                         goto out;
@@ -899,6 +922,8 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
         int     count = 1;
         char    *w = NULL;
         int     index;
+        gf_boolean_t is_force = _gf_false;
+        int wc = wordcount;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -976,7 +1001,13 @@ cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
         brick_index = index;
 
 parse_bricks:
-        ret = cli_cmd_bricks_parse (words, wordcount, brick_index, &bricks,
+
+        if (strcmp (words[wordcount - 1], "force") == 0) {
+                is_force = _gf_true;
+                wc = wordcount - 1;
+        }
+
+        ret = cli_cmd_bricks_parse (words, wc, brick_index, &bricks,
                                     &brick_count);
         if (ret)
                 goto out;
@@ -990,6 +1021,10 @@ parse_bricks:
         if (ret)
                 goto out;
 
+        ret = dict_set_int32 (dict, "force", is_force);
+        if (ret)
+                goto out;
+
         *options = dict;
 
 out:
@@ -1192,6 +1227,7 @@ cli_cmd_volume_replace_brick_parse (const char **words, int wordcount,
         char    *opwords[] = { "start", "commit", "pause", "abort", "status",
                                 NULL };
         char    *w = NULL;
+        gf_boolean_t is_force = _gf_false;
 
         GF_ASSERT (words);
         GF_ASSERT (options);
@@ -1289,12 +1325,17 @@ cli_cmd_volume_replace_brick_parse (const char **words, int wordcount,
         }
 
         if (wordcount == (op_index + 1)) {
-                if (replace_op != GF_REPLACE_OP_COMMIT) {
+                if ((replace_op != GF_REPLACE_OP_COMMIT) &&
+                    (replace_op != GF_REPLACE_OP_START)) {
                         ret = -1;
                         goto out;
                 }
                 if (!strcmp ("force", words[op_index])) {
-                        replace_op = GF_REPLACE_OP_COMMIT_FORCE;
+                        if (replace_op == GF_REPLACE_OP_COMMIT)
+                                replace_op = GF_REPLACE_OP_COMMIT_FORCE;
+
+                        else if (replace_op == GF_REPLACE_OP_START)
+                                is_force = _gf_true;
                 }
         }
 
@@ -1308,6 +1349,9 @@ cli_cmd_volume_replace_brick_parse (const char **words, int wordcount,
         if (ret)
                 goto out;
 
+        ret = dict_set_int32 (dict, "force", is_force);
+        if (ret)
+                goto out;
 
         *options = dict;
 
@@ -1552,22 +1596,161 @@ gsyncd_glob_check (const char *w)
         return !!strpbrk (w, "*?[");
 }
 
+static int
+config_parse (const char **words, int wordcount, dict_t *dict,
+              unsigned cmdi, unsigned glob)
+{
+        int32_t            ret     = -1;
+        int32_t            i       = -1;
+        char               *append_str = NULL;
+        size_t             append_len = 0;
+        char               *subop = NULL;
+
+        switch ((wordcount - 1) - cmdi) {
+        case 0:
+                subop = gf_strdup ("get-all");
+                break;
+        case 1:
+                if (words[cmdi + 1][0] == '!') {
+                        (words[cmdi + 1])++;
+                        if (gf_asprintf (&subop, "del%s",
+                                         glob ? "-glob" : "") == -1)
+                                subop = NULL;
+                } else
+                        subop = gf_strdup ("get");
+
+                ret = dict_set_str (dict, "op_name", ((char *)words[cmdi + 1]));
+                if (ret < 0)
+                        goto out;
+                break;
+        default:
+                if (gf_asprintf (&subop, "set%s", glob ? "-glob" : "") == -1)
+                        subop = NULL;
+
+                ret = dict_set_str (dict, "op_name", ((char *)words[cmdi + 1]));
+                if (ret < 0)
+                        goto out;
+
+                /* join the varargs by spaces to get the op_value */
+
+                for (i = cmdi + 2; i < wordcount; i++)
+                        append_len += (strlen (words[i]) + 1);
+                /* trailing strcat will add two bytes, make space for that */
+                append_len++;
+
+                append_str = GF_CALLOC (1, append_len, cli_mt_append_str);
+                if (!append_str) {
+                        ret = -1;
+                        goto out;
+                }
+
+                for (i = cmdi + 2; i < wordcount; i++) {
+                        strcat (append_str, words[i]);
+                        strcat (append_str, " ");
+                }
+                append_str[append_len - 2] = '\0';
+                /* "checkpoint now" is special: we resolve that "now" */
+                if (strcmp (words[cmdi + 1], "checkpoint") == 0 &&
+                    strcmp (append_str, "now") == 0) {
+                        struct timeval tv = {0,};
+
+                        ret = gettimeofday (&tv, NULL);
+                        if (ret == -1)
+                                goto out; /* FIXME: free append_str? */
+
+                        GF_FREE (append_str);
+                        append_str = GF_CALLOC (1, 300, cli_mt_append_str);
+                        if (!append_str) {
+                                ret = -1;
+                                goto out;
+                        }
+                        strcpy (append_str, "as of ");
+                        gf_time_fmt (append_str + strlen ("as of "),
+                                     300 - strlen ("as of "),
+                                     tv.tv_sec, gf_timefmt_FT);
+                }
+
+                ret = dict_set_dynstr (dict, "op_value", append_str);
+        }
+
+        ret = -1;
+        if (subop) {
+                ret = dict_set_dynstr (dict, "subop", subop);
+                if (!ret)
+                      subop = NULL;
+        }
+
+out:
+        if (ret && append_str)
+                GF_FREE (append_str);
+
+        GF_FREE (subop);
+
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+static int32_t
+force_push_pem_parse (const char **words, int wordcount,
+                      dict_t *dict, unsigned *cmdi)
+{
+        int32_t            ret     = 0;
+
+        if (!strcmp ((char *)words[wordcount-1], "force")) {
+                if ((strcmp ((char *)words[wordcount-2], "start")) &&
+                    (strcmp ((char *)words[wordcount-2], "stop")) &&
+                    (strcmp ((char *)words[wordcount-2], "create")) &&
+                    (strcmp ((char *)words[wordcount-2], "push-pem"))) {
+                        ret = -1;
+                        goto out;
+                }
+                ret = dict_set_uint32 (dict, "force",
+                                       _gf_true);
+                if (ret)
+                        goto out;
+                (*cmdi)++;
+
+                if (!strcmp ((char *)words[wordcount-2], "push-pem")) {
+                        if (strcmp ((char *)words[wordcount-3], "create")) {
+                                ret = -1;
+                                goto out;
+                        }
+                        ret = dict_set_int32 (dict, "push_pem", 1);
+                        if (ret)
+                                goto out;
+                        (*cmdi)++;
+                }
+        } else if (!strcmp ((char *)words[wordcount-1], "push-pem")) {
+                if (strcmp ((char *)words[wordcount-2], "create")) {
+                        ret = -1;
+                        goto out;
+                }
+                ret = dict_set_int32 (dict, "push_pem", 1);
+                if (ret)
+                        goto out;
+                (*cmdi)++;
+        }
+
+out:
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+
 int32_t
 cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
 {
         int32_t            ret     = -1;
         dict_t             *dict   = NULL;
         gf1_cli_gsync_set  type    = GF_GSYNC_OPTION_TYPE_NONE;
-        char               *append_str = NULL;
-        size_t             append_len = 0;
-        char               *subop = NULL;
         int                i       = 0;
         unsigned           masteri = 0;
         unsigned           slavei  = 0;
         unsigned           glob    = 0;
         unsigned           cmdi    = 0;
-        char               *opwords[] = { "status", "start", "stop", "config",
-                                          "log-rotate", NULL };
+        char               *opwords[] = { "create", "status", "start", "stop",
+                                          "config", "force", "delete",
+                                          "push-pem", "detail", NULL };
         char               *w = NULL;
 
         GF_ASSERT (words);
@@ -1579,10 +1762,11 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
 
         /* new syntax:
          *
-         * volume geo-replication [$m [$s]] status
+         * volume geo-replication $m $s create [push-pem] [force]
+         * volume geo-replication [$m [$s]] status [detail]
          * volume geo-replication [$m] $s config [[!]$opt [$val]]
-         * volume geo-replication $m $s start|stop
-         * volume geo-replication $m [$s] log-rotate
+         * volume geo-replication $m $s start|stop [force]
+         * volume geo-replication $m $s delete
          */
 
         if (wordcount < 3)
@@ -1613,6 +1797,13 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
                 if (slavei == 3)
                         masteri = 2;
         } else if (i <= 3) {
+                if (!strcmp ((char *)words[wordcount-1], "detail")) {
+                        /* For status detail it is mandatory to provide
+                         * both master and slave */
+                        ret = -1;
+                        goto out;
+                }
+
                 /* no $s, can only be status cmd
                  * (with either a single $m before it or nothing)
                  * -- these conditions imply that i <= 3 after
@@ -1639,7 +1830,12 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
         if (!w)
                 goto out;
 
-        if (strcmp (w, "status") == 0) {
+        if (strcmp (w, "create") == 0) {
+                type = GF_GSYNC_OPTION_TYPE_CREATE;
+
+                if (!masteri || !slavei)
+                        goto out;
+        } else if (strcmp (w, "status") == 0) {
                 type = GF_GSYNC_OPTION_TYPE_STATUS;
 
                 if (slavei && !masteri)
@@ -1659,14 +1855,33 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
 
                 if (!masteri || !slavei)
                         goto out;
-        } else if (strcmp(w, "log-rotate") == 0) {
-                type = GF_GSYNC_OPTION_TYPE_ROTATE;
+        } else if (strcmp (w, "delete") == 0) {
+                type = GF_GSYNC_OPTION_TYPE_DELETE;
 
-                if (slavei && !masteri)
+                if (!masteri || !slavei)
                         goto out;
         } else
                 GF_ASSERT (!"opword mismatch");
 
+        ret = force_push_pem_parse (words, wordcount, dict, &cmdi);
+        if (ret)
+                goto out;
+
+        if (!strcmp ((char *)words[wordcount-1], "detail")) {
+                if (strcmp ((char *)words[wordcount-2], "status")) {
+                        ret = -1;
+                        goto out;
+                }
+                if (!slavei || !masteri) {
+                        ret = -1;
+                        goto out;
+                }
+                ret = dict_set_uint32 (dict, "status-detail", _gf_true);
+                if (ret)
+                        goto out;
+                cmdi++;
+        }
+
         if (type != GF_GSYNC_OPTION_TYPE_CONFIG &&
             (cmdi < wordcount - 1 || glob))
                 goto out;
@@ -1675,97 +1890,26 @@ cli_cmd_gsync_set_parse (const char **words, int wordcount, dict_t **options)
 
         ret = 0;
 
-        if (masteri)
+        if (masteri) {
                 ret = dict_set_str (dict, "master", (char *)words[masteri]);
+                if (!ret)
+                        ret = dict_set_str (dict, "volname",
+                                            (char *)words[masteri]);
+        }
         if (!ret && slavei)
                 ret = dict_set_str (dict, "slave", (char *)words[slavei]);
         if (!ret)
                 ret = dict_set_int32 (dict, "type", type);
-        if (!ret && type == GF_GSYNC_OPTION_TYPE_CONFIG) {
-                switch ((wordcount - 1) - cmdi) {
-                case 0:
-                        subop = gf_strdup ("get-all");
-                        break;
-                case 1:
-                        if (words[cmdi + 1][0] == '!') {
-                                (words[cmdi + 1])++;
-                                if (gf_asprintf (&subop, "del%s", glob ? "-glob" : "") == -1)
-                                        subop = NULL;
-                        } else
-                                subop = gf_strdup ("get");
-
-                        ret = dict_set_str (dict, "op_name", ((char *)words[cmdi + 1]));
-                        if (ret < 0)
-                                goto out;
-                        break;
-                default:
-                        if (gf_asprintf (&subop, "set%s", glob ? "-glob" : "") == -1)
-                                subop = NULL;
-
-                        ret = dict_set_str (dict, "op_name", ((char *)words[cmdi + 1]));
-                        if (ret < 0)
-                                goto out;
-
-                        /* join the varargs by spaces to get the op_value */
-
-                        for (i = cmdi + 2; i < wordcount; i++)
-                                append_len += (strlen (words[i]) + 1);
-                        /* trailing strcat will add two bytes, make space for that */
-                        append_len++;
-
-                        append_str = GF_CALLOC (1, append_len, cli_mt_append_str);
-                        if (!append_str) {
-                                ret = -1;
-                                goto out;
-                        }
-
-                        for (i = cmdi + 2; i < wordcount; i++) {
-                                strcat (append_str, words[i]);
-                                strcat (append_str, " ");
-                        }
-                        append_str[append_len - 2] = '\0';
-
-                        /* "checkpoint now" is special: we resolve that "now" */
-                        if (strcmp (words[cmdi + 1], "checkpoint") == 0 &&
-                            strcmp (append_str, "now") == 0) {
-                                struct timeval tv = {0,};
-
-                                ret = gettimeofday (&tv, NULL);
-                                if (ret == -1)
-                                         goto out; /* FIXME: free append_str? */
-
-                                GF_FREE (append_str);
-                                append_str = GF_CALLOC (1, 300, cli_mt_append_str);
-                                if (!append_str) {
-                                        ret = -1;
-                                        goto out;
-                                }
-                                strcpy (append_str, "as of ");
-                                gf_time_fmt (append_str + strlen ("as of "),
-                                             300 - strlen ("as of "),
-                                             tv.tv_sec, gf_timefmt_FT);
-                        }
-
-                        ret = dict_set_dynstr (dict, "op_value", append_str);
-                }
-
-                ret = -1;
-                if (subop) {
-                        ret = dict_set_dynstr (dict, "subop", subop);
-                        if (!ret)
-                                subop = NULL;
-                }
-        }
+        if (!ret && type == GF_GSYNC_OPTION_TYPE_CONFIG)
+                ret = config_parse (words, wordcount, dict, cmdi, glob);
 
 out:
         if (ret) {
                 if (dict)
                         dict_destroy (dict);
-                GF_FREE (append_str);
         } else
                 *options = dict;
 
-        GF_FREE (subop);
 
         return ret;
 }
@@ -2025,7 +2169,7 @@ cli_cmd_get_statusop (const char *arg)
         uint32_t   ret       = GF_CLI_STATUS_NONE;
         char      *w         = NULL;
         char      *opwords[] = {"detail", "mem", "clients", "fd",
-                                "inode", "callpool", NULL};
+                                "inode", "callpool", "tasks", NULL};
         struct {
                 char      *opname;
                 uint32_t   opcode;
@@ -2036,6 +2180,7 @@ cli_cmd_get_statusop (const char *arg)
                 { "fd",       GF_CLI_STATUS_FD       },
                 { "inode",    GF_CLI_STATUS_INODE    },
                 { "callpool", GF_CLI_STATUS_CALLPOOL },
+                { "tasks",    GF_CLI_STATUS_TASKS    },
                 { NULL }
         };
 
@@ -2150,8 +2295,9 @@ cli_cmd_volume_status_parse (const char **words, int wordcount,
 
                 if (!strcmp (words[3], "nfs")) {
                         if (cmd == GF_CLI_STATUS_FD ||
-                            cmd == GF_CLI_STATUS_DETAIL) {
-                                cli_err ("Detail/FD status not available"
+                            cmd == GF_CLI_STATUS_DETAIL ||
+                            cmd == GF_CLI_STATUS_TASKS) {
+                                cli_err ("Detail/FD/Tasks status not available"
                                          " for NFS Servers");
                                 ret = -1;
                                 goto out;
@@ -2160,14 +2306,21 @@ cli_cmd_volume_status_parse (const char **words, int wordcount,
                 } else if (!strcmp (words[3], "shd")){
                         if (cmd == GF_CLI_STATUS_FD ||
                             cmd == GF_CLI_STATUS_CLIENTS ||
-                            cmd == GF_CLI_STATUS_DETAIL) {
-                                cli_err ("Detail/FD/Clients status not "
+                            cmd == GF_CLI_STATUS_DETAIL ||
+                            cmd == GF_CLI_STATUS_TASKS) {
+                                cli_err ("Detail/FD/Clients/Tasks status not "
                                          "available for Self-heal Daemons");
                                 ret = -1;
                                 goto out;
                         }
                         cmd |= GF_CLI_STATUS_SHD;
                 } else {
+                        if (cmd == GF_CLI_STATUS_TASKS) {
+                                cli_err ("Tasks status not available for "
+                                         "bricks");
+                                ret = -1;
+                                goto out;
+                        }
                         cmd |= GF_CLI_STATUS_BRICK;
                         ret = dict_set_str (dict, "brick", (char *)words[3]);
                 }
@@ -2316,12 +2469,103 @@ out:
        return ret;
 }
 
+static int
+extract_hostname_path_from_token (const char *tmp_words, char **hostname,
+                                  char **path)
+{
+        int ret = 0;
+        char *delimiter = NULL;
+        char *tmp_host = NULL;
+        char *host_name = NULL;
+        char *words = NULL;
+
+        *hostname = NULL;
+        *path = NULL;
+
+        words = GF_CALLOC (1, strlen (tmp_words) + 1, gf_common_mt_char);
+        if (!words){
+                ret = -1;
+                goto out;
+        }
+
+        strncpy (words, tmp_words, strlen (tmp_words) + 1);
+
+        if (validate_brick_name (words)) {
+                cli_err ("Wrong brick type: %s, use <HOSTNAME>:"
+                        "<export-dir-abs-path>", words);
+                ret = -1;
+                goto out;
+        } else {
+                delimiter = strrchr (words, ':');
+                ret = gf_canonicalize_path (delimiter + 1);
+                if (ret) {
+                        goto out;
+                } else {
+                        *path = GF_CALLOC (1, strlen (delimiter+1) +1,
+                                           gf_common_mt_char);
+                        if (!*path) {
+                           ret = -1;
+                                goto out;
+
+                        }
+                        strncpy (*path, delimiter +1,
+                                 strlen(delimiter + 1) + 1);
+                }
+        }
+
+        tmp_host = gf_strdup (words);
+        if (!tmp_host) {
+                gf_log ("cli", GF_LOG_ERROR, "Out of memory");
+                ret = -1;
+                goto out;
+        }
+        get_host_name (tmp_host, &host_name);
+        if (!host_name) {
+                ret = -1;
+                gf_log("cli",GF_LOG_ERROR, "Unable to allocate "
+                        "memory");
+                goto out;
+        }
+        if (!(strcmp (host_name, "localhost") &&
+            strcmp (host_name, "127.0.0.1") &&
+            strncmp (host_name, "0.", 2))) {
+                cli_err ("Please provide a valid hostname/ip other "
+                         "than localhost, 127.0.0.1 or loopback "
+                         "address (0.0.0.0 to 0.255.255.255).");
+                ret = -1;
+                goto out;
+        }
+        if (!valid_internet_address (host_name, _gf_false)) {
+                cli_err ("internet address '%s' does not conform to "
+                          "standards", host_name);
+                ret = -1;
+                goto out;
+        }
+
+        *hostname = GF_CALLOC (1, strlen (host_name) + 1,
+                                       gf_common_mt_char);
+        if (!*hostname) {
+                ret = -1;
+                goto out;
+        }
+        strncpy (*hostname, host_name, strlen (host_name) + 1);
+        ret = 0;
+
+out:
+        GF_FREE (words);
+        GF_FREE (tmp_host);
+        return ret;
+}
+
+
 int
 cli_cmd_volume_heal_options_parse (const char **words, int wordcount,
                                    dict_t **options)
 {
         int     ret = 0;
         dict_t  *dict = NULL;
+        char    *hostname = NULL;
+        char    *path = NULL;
 
         dict = dict_new ();
         if (!dict)
@@ -2343,6 +2587,11 @@ cli_cmd_volume_heal_options_parse (const char **words, int wordcount,
                         ret = dict_set_int32 (dict, "heal-op",
                                               GF_AFR_OP_HEAL_FULL);
                         goto done;
+                } else if (!strcmp (words[3], "statistics")) {
+                        ret = dict_set_int32 (dict, "heal-op",
+                                              GF_AFR_OP_STATISTICS);
+                        goto done;
+
                 } else if (!strcmp (words[3], "info")) {
                         ret = dict_set_int32 (dict, "heal-op",
                                               GF_AFR_OP_INDEX_SUMMARY);
@@ -2353,28 +2602,66 @@ cli_cmd_volume_heal_options_parse (const char **words, int wordcount,
                 }
         }
         if (wordcount == 5) {
-                if (strcmp (words[3], "info")) {
+                if (strcmp (words[3], "info") &&
+                    strcmp (words[3], "statistics")) {
                         ret = -1;
                         goto out;
                 }
-                if (!strcmp (words[4], "healed")) {
-                        ret = dict_set_int32 (dict, "heal-op",
-                                              GF_AFR_OP_HEALED_FILES);
-                        goto done;
-                }
-                if (!strcmp (words[4], "heal-failed")) {
-                        ret = dict_set_int32 (dict, "heal-op",
-                                              GF_AFR_OP_HEAL_FAILED_FILES);
-                        goto done;
+
+                if (!strcmp (words[3], "info")) {
+                        if (!strcmp (words[4], "healed")) {
+                                ret = dict_set_int32 (dict, "heal-op",
+                                                      GF_AFR_OP_HEALED_FILES);
+                                goto done;
+                        }
+                        if (!strcmp (words[4], "heal-failed")) {
+                                ret = dict_set_int32 (dict, "heal-op",
+                                                   GF_AFR_OP_HEAL_FAILED_FILES);
+                                goto done;
+                        }
+                        if (!strcmp (words[4], "split-brain")) {
+                                ret = dict_set_int32 (dict, "heal-op",
+                                                   GF_AFR_OP_SPLIT_BRAIN_FILES);
+                                goto done;
+                        }
                 }
-                if (!strcmp (words[4], "split-brain")) {
-                        ret = dict_set_int32 (dict, "heal-op",
-                                              GF_AFR_OP_SPLIT_BRAIN_FILES);
-                        goto done;
+
+                if (!strcmp (words[3], "statistics")) {
+                        if (!strcmp (words[4], "heal-count")) {
+                                ret = dict_set_int32 (dict, "heal-op",
+                                               GF_AFR_OP_STATISTICS_HEAL_COUNT);
+                                goto done;
+                        }
                 }
                 ret = -1;
                 goto out;
         }
+        if (wordcount == 7) {
+                if (!strcmp (words[3], "statistics")
+                    && !strcmp (words[4], "heal-count")
+                    && !strcmp (words[5], "replica")) {
+
+                        ret = dict_set_int32 (dict, "heal-op",
+                                   GF_AFR_OP_STATISTICS_HEAL_COUNT_PER_REPLICA);
+                        if (ret)
+                                goto out;
+                        ret = extract_hostname_path_from_token (words[6],
+                                                              &hostname, &path);
+                        if (ret)
+                                goto out;
+                        ret = dict_set_dynstr (dict, "per-replica-cmd-hostname",
+                                               hostname);
+                        if (ret)
+                                goto out;
+                        ret = dict_set_dynstr (dict, "per-replica-cmd-path",
+                                               path);
+                        if (ret)
+                                goto out;
+                        else
+                                goto done;
+
+                }
+        }
         ret = -1;
         goto out;
 done:
@@ -2479,3 +2766,917 @@ out:
 
         return ret;
 }
+
+int32_t
+cli_snap_create_desc_parse (dict_t *dict, const char **words,
+                            size_t wordcount, int32_t desc_opt_loc)
+{
+        int32_t        ret      = -1;
+        char          *desc     = NULL;
+        int32_t        desc_len = 0;
+
+        desc = GF_CALLOC (MAX_SNAP_DESCRIPTION_LEN + 1, sizeof(char),
+                          gf_common_mt_char);
+        if (!desc) {
+                ret = -1;
+                goto out;
+        }
+
+
+        if (strlen (words[desc_opt_loc]) >= MAX_SNAP_DESCRIPTION_LEN) {
+                cli_out ("snapshot create: description truncated: "
+                         "Description provided is longer than 1024 characters");
+                desc_len = MAX_SNAP_DESCRIPTION_LEN;
+        } else {
+                desc_len = strlen (words[desc_opt_loc]);
+        }
+
+        strncpy (desc, words[desc_opt_loc], desc_len);
+        desc[desc_len] = '\0';
+        /* Calculating the size of the description as given by the user */
+
+        ret = dict_set_dynstr (dict, "description", desc);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save snap "
+                        "description");
+                goto out;
+        }
+
+        ret = 0;
+out:
+        if (ret && desc)
+                GF_FREE (desc);
+
+        return ret;
+}
+
+/* Function to check whether the Volume name is repeated */
+int
+cli_check_if_volname_repeated (const char **words, unsigned int start_index,
+                           uint64_t cur_index) {
+        uint64_t        i       =       -1;
+        int             ret     =        0;
+
+        GF_ASSERT (words);
+
+        for (i = start_index ; i < cur_index ; i++) {
+                if (strcmp (words[i], words[cur_index]) == 0) {
+                        ret = -1;
+                        goto out;
+                }
+        }
+out :
+        return ret;
+}
+
+/* snapshot create <snapname> <vol-name(s)> [description <description>]
+ *                                           [force]
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_create_parse (dict_t *dict, const char **words, int wordcount) {
+        uint64_t        i               =        0;
+        int             ret             =       -1;
+        uint64_t        volcount        =        0;
+        char            key[PATH_MAX]   =        "";
+        char            *snapname       =       NULL;
+        unsigned int    cmdi            =        2;
+        /* cmdi is command index, here cmdi is "2" (gluster snapshot create)*/
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount <= cmdi + 1) {
+                cli_err ("Invalid Syntax.");
+                gf_log ("cli", GF_LOG_ERROR,
+                        "Too less words for snap create command");
+                goto out;
+        }
+
+        if (strlen(words[cmdi]) >= GLUSTERD_MAX_SNAP_NAME) {
+                cli_err ("snapshot create: failed: snapname cannot exceed "
+                         "255 characters.");
+                gf_log ("cli", GF_LOG_ERROR, "Snapname too long");
+
+                goto out;
+        }
+
+        snapname = (char *) words[cmdi];
+        for (i = 0 ; i < strlen (snapname); i++) {
+                /* Following volume name convention */
+                if (!isalnum (snapname[i]) && (snapname[i] != '_'
+                                           && (snapname[i] != '-'))) {
+                        /* TODO : Is this message enough?? */
+                        cli_err ("Snapname can contain only alphanumeric, "
+                                 "\"-\" and \"_\" characters");
+                        goto out;
+                }
+        }
+
+        ret = dict_set_str (dict, "snapname", (char *)words[cmdi]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not save snap "
+                        "name");
+                goto out;
+        }
+
+        /* Filling volume name in the dictionary */
+        for (i = cmdi + 1 ; i < wordcount
+                            && (strcmp (words[i], "description")) != 0
+                            && (strcmp (words[i], "force") != 0); i++) {
+                volcount++;
+                /* volume index starts from 1 */
+                ret = snprintf (key, sizeof (key),"volname%ld", volcount);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_set_str (dict, key, (char *)words[i]);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not "
+                                "save volume name");
+                        goto out;
+                }
+
+                if (i >= cmdi + 2) {
+                        ret = -1;
+                        cli_err("Creating multiple volume snapshot is not "
+                                "supported as of now");
+                        goto out;
+                }
+                /* TODO : remove this above condition check once
+                 * multiple volume snapshot is supported */
+        }
+
+        if (volcount == 0) {
+                ret = -1;
+                cli_err ("Please provide the volume name");
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_int32 (dict, "volcount", volcount);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not save volcount");
+                goto out;
+        }
+
+        /* Verify how we got out of "for" loop,
+         * if it is by reaching wordcount limit then goto "out",
+         * because we need not parse for "description" and "force"
+         * after this.
+         */
+        if (i == wordcount) {
+                goto out;
+        }
+
+        if ((strcmp (words[i], "description")) == 0) {
+                ++i;
+                if (i > (wordcount - 1)) {
+                        ret = -1;
+                        cli_err ("Please provide a description");
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Description not provided");
+                        goto out;
+                }
+
+                ret = cli_snap_create_desc_parse(dict, words, wordcount, i);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not save snap "
+                                "description");
+                        goto out;
+                }
+
+                if ( i == (wordcount - 1))
+                        goto out;
+                i++;
+                /* point the index to next word.
+                 * As description might be follwed by force option.
+                 * Before that, check if wordcount limit is reached
+                 */
+        }
+
+        if ((strcmp (words[i], "force") != 0)) {
+                ret = -1;
+                cli_err ("Invalid Syntax.");
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+        ret = dict_set_int8 (dict, "snap-force", 1);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not save "
+                        "snap force option");
+                goto out;
+        }
+
+        /* Check if the command has anything after "force" keyword */
+        if (++i < wordcount) {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = 0;
+
+out :
+        return ret;
+}
+
+/* snapshot list [volname]
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_list_parse (dict_t *dict, const char **words, int wordcount) {
+        int             ret     =       -1;
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount < 2 || wordcount > 3) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        if (wordcount == 2) {
+                ret = 0;
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "volname", (char *)words[2]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR,
+                        "Failed to save volname in dictionary");
+                goto out;
+        }
+out :
+        return ret;
+}
+
+/* snapshot info [(snapname |  volume <volname>)]
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_info_parse (dict_t *dict, const char **words, int wordcount)
+{
+
+        int             ret             =       -1;
+        int32_t         cmd             =       GF_SNAP_INFO_TYPE_ALL;
+        unsigned int    cmdi            =        2;
+        /* cmdi is command index, here cmdi is "2" (gluster snapshot info)*/
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount > 4 || wordcount < cmdi) {
+                gf_log ("", GF_LOG_ERROR, "Invalid syntax");
+                goto out;
+        }
+
+        if (wordcount == cmdi) {
+                ret = 0;
+                goto out;
+        }
+
+        /* If 3rd word is not "volume", then it must
+         * be snapname.
+         */
+        if (strcmp (words[cmdi], "volume") != 0) {
+                ret = dict_set_str (dict, "snapname",
+                                   (char *)words[cmdi]);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Unable to save "
+                                "snapname %s", words[cmdi]);
+                        goto out;
+                }
+
+                /* Once snap name is parsed, if we encounter any other
+                 * word then fail it. Invalid Syntax.
+                 * example : snapshot info <snapname> word
+                 */
+                if ((cmdi + 1) != wordcount) {
+                        ret = -1;
+                        gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                        goto out;
+                }
+
+                cmd = GF_SNAP_INFO_TYPE_SNAP;
+                ret = 0;
+                goto out;
+                /* No need to continue the parsing once we
+                 * get the snapname
+                 */
+        }
+
+        /* If 3rd word is "volume", then check if next word
+         * is present. As, "snapshot info volume" is an
+         * invalid command.
+         */
+        if ((cmdi + 1) == wordcount) {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "volname", (char *)words[wordcount - 1]);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR, "Count not save "
+                        "volume name %s", words[wordcount - 1]);
+                goto out;
+        }
+        cmd = GF_SNAP_INFO_TYPE_VOL;
+out :
+        if (ret == 0) {
+                ret = dict_set_int32 (dict, "cmd", cmd);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not save "
+                                "type of snapshot info");
+                }
+        }
+        return ret;
+}
+
+
+
+/* snapshot restore <snapname>
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_restore_parse (dict_t *dict, const char **words, int wordcount)
+{
+
+        int             ret             =       -1;
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount != 3) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "snapname", (char *)words[2]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save snap-name %s",
+                        words[2]);
+                goto out;
+        }
+out :
+        return ret;
+}
+
+/* snapshot delete <snapname>
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ *                 1 if user cancel the operation
+ */
+int
+cli_snap_delete_parse (dict_t *dict, const char **words, int wordcount,
+                       struct cli_state *state) {
+
+        int             ret             =       -1;
+        const char      *question       =       NULL;
+        gf_answer_t     answer          =       GF_ANSWER_NO;
+
+        question = "Deleting snap will erase all the information about "
+                   "the snap. Do you still want to continue?";
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount != 3) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "snapname", (char *)words[2]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to save snapname %s",
+                        words[2]);
+                goto out;
+        }
+
+        answer = cli_cmd_get_confirmation (state, question);
+        if (GF_ANSWER_NO == answer) {
+                ret = 1;
+                gf_log ("cli", GF_LOG_DEBUG, "User cancelled "
+                        "snapshot delete operation");
+                goto out;
+        }
+out :
+        return ret;
+}
+
+/* snapshot status [(snapname | volume <volname>)]
+ * @arg-0, dict     : Request Dictionary to be sent to server side.
+ * @arg-1, words    : Contains individual words of CLI command.
+ * @arg-2, wordcount: Contains number of words present in the CLI command.
+ *
+ * return value : -1 on failure
+ *                 0 on success
+ */
+int
+cli_snap_status_parse (dict_t *dict, const char **words, int wordcount)
+{
+
+        int             ret  =        -1;
+        int32_t         cmd  =       GF_SNAP_STATUS_TYPE_ALL;
+        unsigned int    cmdi =        2;
+        /* cmdi is command index, here cmdi is "2" (gluster snapshot status)*/
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+
+        if (wordcount > 4 || wordcount < cmdi) {
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        if (wordcount == cmdi) {
+                ret = 0;
+                goto out;
+        }
+
+        /* if 3rd word is not "volume", then it must be "snapname"
+        */
+        if (strcmp (words[cmdi], "volume") != 0) {
+                ret = dict_set_str (dict, "snapname",
+                                   (char *)words[cmdi]);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Count not save "
+                                "snap name %s", words[cmdi]);
+                        goto out;
+                }
+
+                if ((cmdi + 1) != wordcount) {
+                        ret = -1;
+                        gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                        goto out;
+                }
+
+                ret = 0;
+                cmd = GF_SNAP_STATUS_TYPE_SNAP;
+                goto out;
+        }
+
+        /* If 3rd word is "volume", then check if next word is present.
+         * As, "snapshot info volume" is an invalid command
+         */
+        if ((cmdi + 1) == wordcount) {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "volname", (char *)words [wordcount - 1]);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Count not save "
+                        "volume name %s", words[wordcount - 1]);
+                goto out;
+        }
+        cmd = GF_SNAP_STATUS_TYPE_VOL;
+
+out :
+        if (ret == 0) {
+                ret = dict_set_int32 (dict, "cmd", cmd);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not save cmd "
+                                "of snapshot status");
+                }
+        }
+        return ret;
+}
+
+
+int32_t
+cli_snap_config_limit_parse (const char **words, dict_t *dict,
+                             unsigned int wordcount, unsigned int index,
+                             char *key)
+{
+        int             ret             =       -1;
+        int             limit           =       0;
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+        GF_ASSERT (key);
+
+        if (index >= wordcount) {
+                ret = -1;
+                cli_err ("Please provide a value for %s.",key);
+                gf_log ("cli", GF_LOG_ERROR, "Value not provided for %s", key);
+                goto out;
+        }
+
+        limit = strtol (words[index], NULL, 0);
+        if (limit <= 0) {
+                ret = -1;
+                cli_err ("%s should be greater than 0.", key);
+                goto out;
+        }
+
+        ret = dict_set_int32 (dict, key, limit);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not set "
+                        "%s in dictionary", key);
+                goto out;
+        }
+
+out :
+        return ret;
+}
+
+/* function cli_snap_config_parse
+ * Config Syntax : gluster snapshot config [volname]
+ *                                         [snap-max-hard-limit <count>]
+ *                                         [snap-max-soft-limit <count>]
+ *
+   return value: <0  on failure
+                  1  if user cancels the operation
+                  0  on success
+
+  NOTE : snap-max-soft-limit can only be set for system.
+*/
+int32_t
+cli_snap_config_parse (const char **words, int wordcount, dict_t *dict,
+                       struct cli_state *state)
+{
+        int                            ret                 = -1;
+        gf_answer_t                    answer              = GF_ANSWER_NO;
+        gf_boolean_t                   vol_presence        = _gf_false;
+        struct snap_config_opt_vals_  *conf_vals           = NULL;
+        int8_t                         hard_limit          = 0;
+        int8_t                         soft_limit          = 0;
+        int8_t                         config_type         = -1;
+        const char                    *question            = NULL;
+        unsigned int                    cmdi               = 2;
+        /* cmdi is command index, here cmdi is "2" (gluster snapshot config)*/
+
+        GF_ASSERT (words);
+        GF_ASSERT (dict);
+        GF_ASSERT (state);
+
+        if ((wordcount < 2) || (wordcount > 7)) {
+                gf_log ("cli", GF_LOG_ERROR,
+                        "Invalid wordcount(%d)", wordcount);
+                goto out;
+        }
+
+        if (wordcount == 2) {
+                config_type = GF_SNAP_CONFIG_DISPLAY;
+                ret = 0;
+                goto set;
+        }
+
+        /* Check whether the 3rd word is volname */
+        if (strcmp (words[cmdi], "snap-max-hard-limit") != 0
+             && strcmp (words[cmdi], "snap-max-soft-limit") != 0) {
+                ret = dict_set_str (dict, "volname", (char *)words[cmdi]);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to set volname");
+                        goto out;
+                }
+                cmdi++;
+                vol_presence = _gf_true;
+
+                if (cmdi == wordcount) {
+                        config_type = GF_SNAP_CONFIG_DISPLAY;
+                        ret = 0;
+                        goto set;
+                }
+        }
+
+        config_type = GF_SNAP_CONFIG_TYPE_SET;
+
+        if (strcmp (words[cmdi], "snap-max-hard-limit") == 0) {
+                ret = cli_snap_config_limit_parse (words, dict, wordcount,
+                                                ++cmdi, "snap-max-hard-limit");
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to parse snap "
+                                "config hard limit");
+                        goto out;
+                }
+                hard_limit = 1;
+
+                if (++cmdi == wordcount) {
+                        ret = 0;
+                        goto set;
+                }
+        }
+
+        if (strcmp (words[cmdi], "snap-max-soft-limit") == 0) {
+                if (vol_presence == 1) {
+                        ret = -1;
+                        cli_err ("Soft limit cannot be set to individual "
+                                  "volumes.");
+                        gf_log ("cli", GF_LOG_ERROR, "Soft limit cannot be "
+                                "set to volumes");
+                        goto out;
+                }
+
+                ret = cli_snap_config_limit_parse (words, dict, wordcount,
+                                                ++cmdi, "snap-max-soft-limit");
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to parse snap "
+                                "config soft limit");
+                        goto out;
+                }
+
+                if (++cmdi != wordcount) {
+                        ret = -1;
+                        gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                        goto out;
+                }
+                soft_limit = 1;
+        } else {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
+                goto out;
+        }
+        ret = 0; /* Success */
+
+set:
+        ret = dict_set_int32 (dict, "config-command", config_type);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to set "
+                        "config-command");
+                goto out;
+        }
+
+        if (config_type == GF_SNAP_CONFIG_TYPE_SET) {
+                conf_vals = snap_confopt_vals;
+                if (hard_limit && soft_limit) {
+                        question = conf_vals[GF_SNAP_CONFIG_SET_BOTH].question;
+                } else if (soft_limit) {
+                        question = conf_vals[GF_SNAP_CONFIG_SET_SOFT].question;
+                } else if (hard_limit) {
+                        question = conf_vals[GF_SNAP_CONFIG_SET_HARD].question;
+                }
+
+                answer = cli_cmd_get_confirmation (state, question);
+                if (GF_ANSWER_NO == answer) {
+                        ret = 1;
+                        gf_log ("cli", GF_LOG_DEBUG, "User cancelled "
+                        "snapshot config operation");
+                }
+        }
+
+out:
+        return ret;
+}
+
+int
+validate_snapname (const char *snapname, char **opwords) {
+        int     ret     =       -1;
+        int     i       =       0;
+
+        GF_ASSERT (snapname);
+        GF_ASSERT (opwords);
+
+        for (i = 0 ; opwords[i] != NULL; i++) {
+                if (strcmp (opwords[i], snapname) == 0) {
+                        cli_out ("\"%s\" cannot be a snapname", snapname);
+                        goto out;
+                }
+        }
+        ret = 0;
+out :
+        return ret;
+}
+
+int32_t
+cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
+                        struct cli_state *state)
+{
+        int32_t            ret        = -1;
+        dict_t             *dict      = NULL;
+        gf1_cli_snapshot   type       = GF_SNAP_OPTION_TYPE_NONE;
+        char               *w         = NULL;
+        char               *opwords[] = {"create", "delete", "restore", "start",
+                                         "stop", "list", "status", "config",
+                                         "info", NULL};
+        char               *invalid_snapnames[] = {"description", "force",
+                                                  "volume", NULL};
+
+        GF_ASSERT (words);
+        GF_ASSERT (options);
+        GF_ASSERT (state);
+
+        dict = dict_new ();
+        if (!dict)
+                goto out;
+
+        /* Lowest wordcount possible */
+        if (wordcount < 2) {
+                gf_log ("", GF_LOG_ERROR,
+                        "Invalid command: Not enough arguments");
+                goto out;
+        }
+
+        w = str_getunamb (words[1], opwords);
+        if (!w) {
+                /* Checks if the operation is a valid operation */
+                gf_log ("", GF_LOG_ERROR, "Opword Mismatch");
+                goto out;
+        }
+
+        if (!strcmp (w, "create")) {
+                type = GF_SNAP_OPTION_TYPE_CREATE;
+        } else if (!strcmp (w, "list")) {
+                type = GF_SNAP_OPTION_TYPE_LIST;
+        } else if (!strcmp (w, "info")) {
+                type = GF_SNAP_OPTION_TYPE_INFO;
+        } else if (!strcmp (w, "delete")) {
+                type = GF_SNAP_OPTION_TYPE_DELETE;
+        } else if (!strcmp (w, "config")) {
+                type = GF_SNAP_OPTION_TYPE_CONFIG;
+        } else if (!strcmp (w, "restore")) {
+                type = GF_SNAP_OPTION_TYPE_RESTORE;
+        } else if (!strcmp (w, "status")) {
+                type = GF_SNAP_OPTION_TYPE_STATUS;
+        }
+
+        if (type != GF_SNAP_OPTION_TYPE_CONFIG) {
+                ret = dict_set_int32 (dict, "hold_snap_locks", _gf_true);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Unable to set hold-snap-locks value "
+                                "as _gf_true");
+                        goto out;
+                }
+        }
+
+        /* Check which op is intended */
+        switch (type) {
+               case GF_SNAP_OPTION_TYPE_CREATE:
+               {
+                        /* Syntax :
+                         * gluster snapshot create <snapname> <vol-name(s)>
+                         *                         [description <description>]
+                         *                         [force]
+                         */
+
+                        /* In cases where the snapname is not given then
+                         * parsing fails & snapname cannot be "description",
+                         * "force" and "volume", that check is made here
+                         */
+                       if (wordcount == 2){
+                                ret = -1;
+                                gf_log ("cli", GF_LOG_ERROR,
+                                        "Invalid Syntax");
+                                goto out;
+                       }
+
+                       ret = validate_snapname (words[2], invalid_snapnames);
+                       if (ret) {
+                               goto out;
+                       }
+
+                       ret = cli_snap_create_parse (dict, words, wordcount);
+                       if (ret) {
+                               gf_log ("cli", GF_LOG_ERROR,
+                                       "create command parsing failed.");
+                               goto out;
+                       }
+                       break;
+               }
+                case GF_SNAP_OPTION_TYPE_INFO:
+                {
+                        /* Syntax :
+                         * gluster snapshot info [(snapname] | [vol <volname>)]
+                         */
+                        ret = cli_snap_info_parse (dict, words, wordcount);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "snapshot info command");
+                                goto out;
+                        }
+                        break;
+                }
+
+                case GF_SNAP_OPTION_TYPE_LIST:
+                {
+                        /* Syntax :
+                         * gluster snaphsot list [volname]
+                         */
+
+                        ret = cli_snap_list_parse (dict, words, wordcount);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "snapshot list command");
+                                goto out;
+                        }
+                        break;
+                }
+
+                case GF_SNAP_OPTION_TYPE_DELETE:
+                {
+                        /* Syntax :
+                         * gluster snapshot delete <snapname>
+                         */
+                        ret = cli_snap_delete_parse (dict, words, wordcount,
+                                                     state);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "snapshot delete command");
+                                goto out;
+                        }
+                        break;
+                }
+
+               case GF_SNAP_OPTION_TYPE_CONFIG:
+               {
+                /* snapshot config [volname]  [snap-max-hard-limit <count>]
+                 *                            [snap-max-soft-limit <percent>] */
+                       ret = cli_snap_config_parse (words, wordcount, dict,
+                                                    state);
+                       if (ret) {
+                                if (ret < 0)
+                                        gf_log ("cli", GF_LOG_ERROR,
+                                              "config command parsing failed.");
+                               goto out;
+                       }
+
+                       ret = dict_set_int32 (dict, "type",
+                                             GF_SNAP_OPTION_TYPE_CONFIG);
+                       if (ret) {
+                               gf_log ("cli", GF_LOG_ERROR, "Unable to set "
+                                       "config type");
+                               ret = -1;
+                               goto out;
+                       }
+                       break;
+               }
+                case GF_SNAP_OPTION_TYPE_STATUS:
+                {
+                        /* Syntax :
+                         * gluster snapshot status [(snapname |
+                         *                         volume <volname>)]
+                         */
+                        ret = cli_snap_status_parse (dict, words, wordcount);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                        "snapshot status command");
+                                goto out;
+                        }
+                        break;
+                }
+
+               case GF_SNAP_OPTION_TYPE_RESTORE:
+               {
+                       /* Syntax:
+                        * snapshot restore <snapname>
+                        */
+                       ret = cli_snap_restore_parse (dict, words, wordcount);
+                       if (ret) {
+                               gf_log ("cli", GF_LOG_ERROR, "Failed to parse "
+                                       "restore command");
+                               goto out;
+                       }
+                       break;
+               }
+               default:
+                       gf_log ("", GF_LOG_ERROR, "Opword Mismatch");
+                       goto out;
+                       break;
+        }
+
+        ret = dict_set_int32 (dict, "type", type);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR,
+                        "Failed to set type.");
+                goto out;
+        }
+        /* If you got so far, input is valid */
+        ret = 0;
+out:
+        if (ret) {
+                if (dict)
+                        dict_destroy (dict);
+        } else
+                *options = dict;
+
+        return ret;
+}
diff --git a/cli/src/cli-cmd-peer.c b/cli/src/cli-cmd-peer.c
index 08651e72f..551312411 100644
--- a/cli/src/cli-cmd-peer.c
+++ b/cli/src/cli-cmd-peer.c
@@ -41,6 +41,7 @@ cli_cmd_peer_probe_cbk (struct cli_state *state, struct cli_cmd_word *word,
         dict_t                  *dict = NULL;
         int                     sent = 0;
         int                     parse_error = 0;
+        cli_local_t             *local = NULL;
 
         if (!(wordcount == 3)) {
                 cli_usage_out (word->pattern);
@@ -78,6 +79,9 @@ cli_cmd_peer_probe_cbk (struct cli_state *state, struct cli_cmd_word *word,
                         goto out;
         }
 */
+
+        CLI_LOCAL_INIT (local, words, frame, dict);
+
         if (proc->fn) {
                 ret = proc->fn (frame, THIS, dict);
         }
@@ -106,6 +110,7 @@ cli_cmd_peer_deprobe_cbk (struct cli_state *state, struct cli_cmd_word *word,
         int                  flags = 0;
         int                  sent = 0;
         int                  parse_error = 0;
+        cli_local_t          *local = NULL;
 
         if ((wordcount < 3) || (wordcount > 4)) {
                 cli_usage_out (word->pattern);
@@ -145,6 +150,8 @@ cli_cmd_peer_deprobe_cbk (struct cli_state *state, struct cli_cmd_word *word,
         if (ret)
                 goto out;
 
+        CLI_LOCAL_INIT (local, words, frame, dict);
+
         if (proc->fn) {
                 ret = proc->fn (frame, THIS, dict);
         }
@@ -184,7 +191,7 @@ cli_cmd_peer_status_cbk (struct cli_state *state, struct cli_cmd_word *word,
                 goto out;
 
         if (proc->fn) {
-                ret = proc->fn (frame, THIS, (char *)words[1] );
+                ret = proc->fn (frame, THIS, (void *)GF_CLI_LIST_PEERS);
         }
 
 out:
@@ -199,6 +206,45 @@ out:
         return ret;
 }
 
+int
+cli_cmd_pool_list_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                       const char **words, int wordcount)
+{
+        int                     ret = -1;
+        rpc_clnt_procedure_t    *proc = NULL;
+        call_frame_t            *frame = NULL;
+        int                     sent = 0;
+        int                     parse_error = 0;
+
+        if (wordcount != 2) {
+                cli_usage_out (word->pattern);
+                parse_error = 1;
+                goto out;
+        }
+
+        proc = &cli_rpc_prog->proctable[GLUSTER_CLI_LIST_FRIENDS];
+
+        frame = create_frame (THIS, THIS->ctx->pool);
+        if (!frame)
+                goto out;
+
+        if (proc->fn) {
+                ret = proc->fn (frame, THIS,
+                                (void *)GF_CLI_LIST_POOL_NODES);
+        }
+
+out:
+        if (ret) {
+                cli_cmd_sent_status_get (&sent);
+                if ((sent == 0) && (parse_error == 0))
+                        cli_err ("pool list: command execution failed");
+        }
+
+        CLI_STACK_DESTROY (frame);
+
+        return ret;
+}
+
 struct cli_cmd cli_probe_cmds[] = {
         { "peer probe <HOSTNAME>",
           cli_cmd_peer_probe_cbk,
@@ -216,6 +262,10 @@ struct cli_cmd cli_probe_cmds[] = {
            cli_cmd_peer_help_cbk,
            "Help command for peer "},
 
+        { "pool list",
+          cli_cmd_pool_list_cbk,
+          "list all the nodes in the pool (including localhost)"},
+
         { NULL, NULL, NULL }
 };
 
diff --git a/cli/src/cli-cmd-snapshot.c b/cli/src/cli-cmd-snapshot.c
new file mode 100644
index 000000000..de492d683
--- /dev/null
+++ b/cli/src/cli-cmd-snapshot.c
@@ -0,0 +1,146 @@
+/*
+   Copyright (c) 2013-2014 Red Hat, Inc. <http://www.redhat.com>
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <pthread.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "cli.h"
+#include "cli-cmd.h"
+
+extern rpc_clnt_prog_t *cli_rpc_prog;
+
+int
+cli_cmd_snapshot_help_cbk (struct cli_state *state, struct cli_cmd_word *in_word,
+                           const char **words, int wordcount);
+
+int
+cli_cmd_snapshot_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                      const char **words, int wordcount)
+{
+        int                      ret       = 0;
+        int                      parse_err = 0;
+        dict_t                  *options   = NULL;
+        rpc_clnt_procedure_t    *proc      = NULL;
+        call_frame_t            *frame     = NULL;
+        cli_local_t             *local     = NULL;
+
+        proc = &cli_rpc_prog->proctable [GLUSTER_CLI_SNAP];
+        if (proc == NULL) {
+               ret = -1;
+                goto out;
+        }
+
+        frame = create_frame (THIS, THIS->ctx->pool);
+        if (frame == NULL) {
+                ret = -1;
+                goto out;
+        }
+
+        /* Parses the command entered by the user */
+        ret = cli_cmd_snapshot_parse (words, wordcount, &options, state);
+        if (ret) {
+                if (ret < 0) {
+                        cli_usage_out (word->pattern);
+                        parse_err = 1;
+                }
+                else {
+                        /* User might have cancelled the snapshot operation */
+                        ret = 0;
+                }
+                goto out;
+        }
+
+        CLI_LOCAL_INIT (local, words, frame, options);
+
+        if (proc->fn)
+                ret = proc->fn (frame, THIS, options);
+
+out:
+        if (ret && parse_err == 0)
+                cli_out ("Snapshot command failed");
+
+        CLI_STACK_DESTROY (frame);
+
+        return ret;
+}
+
+struct cli_cmd snapshot_cmds[] = {
+        { "snapshot help",
+          cli_cmd_snapshot_help_cbk,
+          "display help for snapshot commands"
+        },
+        { "snapshot create <snapname> <volname(s)> [description <description>] [force]",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Create."
+        },
+        { "snapshot restore <snapname>",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Restore."
+        },
+        { "snapshot status [(snapname | volume <volname>)]",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Status."
+        },
+        { "snapshot info [(snapname | volume <volname>)]",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Info."
+        },
+        { "snapshot list [volname]",
+          cli_cmd_snapshot_cbk,
+          "Snapshot List."
+        },
+        {"snapshot config [volname] [snap-max-hard-limit <count>] [snap-max-soft-limit <percent>]",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Config."
+        },
+        {"snapshot delete <snapname>",
+          cli_cmd_snapshot_cbk,
+          "Snapshot Delete."
+        },
+        { NULL, NULL, NULL }
+};
+
+int
+cli_cmd_snapshot_help_cbk (struct cli_state *state,
+                           struct cli_cmd_word *in_word,
+                           const char **words,
+                           int wordcount)
+{
+        struct cli_cmd        *cmd = NULL;
+
+        for (cmd = snapshot_cmds; cmd->pattern; cmd++)
+                if (_gf_false == cmd->disable)
+                        cli_out ("%s - %s", cmd->pattern, cmd->desc);
+
+        return 0;
+}
+
+int
+cli_cmd_snapshot_register (struct cli_state *state)
+{
+        int  ret = 0;
+        struct cli_cmd *cmd = NULL;
+
+        for (cmd = snapshot_cmds; cmd->pattern; cmd++) {
+
+                ret = cli_cmd_register (&state->tree, cmd);
+                if (ret)
+                        goto out;
+        }
+out:
+        return ret;
+}
diff --git a/cli/src/cli-cmd-system.c b/cli/src/cli-cmd-system.c
index b969c227b..8cfa5e70c 100644
--- a/cli/src/cli-cmd-system.c
+++ b/cli/src/cli-cmd-system.c
@@ -31,6 +31,12 @@ extern rpc_clnt_prog_t *cli_rpc_prog;
 int cli_cmd_system_help_cbk (struct cli_state *state, struct cli_cmd_word *in_word,
                              const char **words, int wordcount);
 
+int cli_cmd_copy_file_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                           const char **words, int wordcount);
+
+int cli_cmd_sys_exec_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                          const char **words, int wordcount);
+
 int
 cli_cmd_getspec_cbk (struct cli_state *state, struct cli_cmd_word *word,
                      const char **words, int wordcount)
@@ -279,6 +285,53 @@ cli_cmd_umount_cbk (struct cli_state *state, struct cli_cmd_word *word,
 }
 
 int
+cli_cmd_uuid_get_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                      const char **words, int wordcount)
+{
+        int                     ret = -1;
+        int                     sent = 0;
+        int                     parse_error = 0;
+        dict_t                  *dict  = NULL;
+        rpc_clnt_procedure_t    *proc = NULL;
+        call_frame_t            *frame = NULL;
+        cli_local_t             *local = NULL;
+        xlator_t                *this  = NULL;
+
+        this = THIS;
+        if (wordcount != 3) {
+                cli_usage_out (word->pattern);
+                parse_error = 1;
+                goto out;
+        }
+
+        proc = &cli_rpc_prog->proctable[GLUSTER_CLI_UUID_GET];
+        frame = create_frame (this, this->ctx->pool);
+        if (!frame)
+                goto out;
+
+        dict = dict_new ();
+        if (!dict)
+                goto out;
+
+        CLI_LOCAL_INIT (local, words, frame, dict);
+        if (proc->fn)
+                ret = proc->fn (frame, this, dict);
+
+out:
+        if (ret) {
+                cli_cmd_sent_status_get (&sent);
+                if ((sent == 0) && (parse_error == 0))
+                        cli_out ("uuid get failed");
+        }
+
+        if (dict)
+                dict_unref (dict);
+
+        CLI_STACK_DESTROY (frame);
+        return ret;
+}
+
+int
 cli_cmd_uuid_reset_cbk (struct cli_state *state, struct cli_cmd_word *word,
                         const char **words, int wordcount)
 {
@@ -364,6 +417,10 @@ struct cli_cmd cli_system_cmds[] = {
           cli_cmd_umount_cbk,
           "request an umount"},
 
+        { "system:: uuid get",
+          cli_cmd_uuid_get_cbk,
+          "get uuid of glusterd"},
+
         { "system:: uuid reset",
           cli_cmd_uuid_reset_cbk,
           "reset the uuid of glusterd"},
@@ -372,10 +429,151 @@ struct cli_cmd cli_system_cmds[] = {
            cli_cmd_system_help_cbk,
            "display help for system commands"},
 
+        { "system:: copy file [<filename>]",
+           cli_cmd_copy_file_cbk,
+           "Copy file from current node's $working_dir to "
+           "$working_dir of all cluster nodes"},
+
+        { "system:: execute <command> <args>",
+           cli_cmd_sys_exec_cbk,
+           "Execute the command on all the nodes "
+           "in the cluster and display their output."},
+
         { NULL, NULL, NULL }
 };
 
 int
+cli_cmd_sys_exec_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                      const char **words, int wordcount)
+{
+        char                   cmd_arg_name[PATH_MAX] = "";
+        char                  *command                = NULL;
+        char                  *saveptr                = NULL;
+        char                  *tmp                    = NULL;
+        int                    ret                    = -1;
+        int                    i                      = -1;
+        int                    cmd_args_count         = 0;
+        int                    in_cmd_args_count      = 0;
+        rpc_clnt_procedure_t  *proc                   = NULL;
+        call_frame_t          *frame                  = NULL;
+        dict_t                *dict                   = NULL;
+        cli_local_t           *local                  = NULL;
+
+        if (wordcount < 3) {
+                cli_usage_out (word->pattern);
+                goto out;
+        }
+
+        dict = dict_new ();
+        if (!dict)
+                goto out;
+
+        command = strtok_r ((char *)words[2], " ", &saveptr);
+        do {
+                tmp = strtok_r (NULL, " ", &saveptr);
+                if (tmp) {
+                        in_cmd_args_count++;
+                        memset (cmd_arg_name, '\0', sizeof(cmd_arg_name));
+                        snprintf (cmd_arg_name, sizeof(cmd_arg_name),
+                                  "cmd_arg_%d", in_cmd_args_count);
+                        ret = dict_set_str (dict, cmd_arg_name, tmp);
+                        if (ret) {
+                                gf_log ("", GF_LOG_ERROR, "Unable to set "
+                                        "%s in dict", cmd_arg_name);
+                                goto out;
+                        }
+                }
+        } while (tmp);
+
+        cmd_args_count = wordcount - 3;
+
+        ret = dict_set_str (dict, "command", command);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR, "Unable to set command in dict");
+                goto out;
+        }
+
+        for (i=1; i <= cmd_args_count; i++) {
+                in_cmd_args_count++;
+                memset (cmd_arg_name, '\0', sizeof(cmd_arg_name));
+                snprintf (cmd_arg_name, sizeof(cmd_arg_name),
+                          "cmd_arg_%d", in_cmd_args_count);
+                ret = dict_set_str (dict, cmd_arg_name,
+                                    (char *)words[2+i]);
+                if (ret) {
+                        gf_log ("", GF_LOG_ERROR, "Unable to set %s in dict",
+                               cmd_arg_name);
+                        goto out;
+                }
+        }
+
+        ret = dict_set_int32 (dict, "cmd_args_count", in_cmd_args_count);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR,
+                        "Unable to set cmd_args_count in dict");
+                goto out;
+        }
+
+        ret = dict_set_str (dict, "volname", "N/A");
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR, "Unable to set volname in dict");
+                goto out;
+        }
+
+        proc = &cli_rpc_prog->proctable[GLUSTER_CLI_SYS_EXEC];
+        if (proc && proc->fn) {
+                frame = create_frame (THIS, THIS->ctx->pool);
+                if (!frame)
+                        goto out;
+                CLI_LOCAL_INIT (local, words, frame, dict);
+                ret = proc->fn (frame, THIS, (void*)dict);
+        }
+out:
+        return ret;
+}
+
+int
+cli_cmd_copy_file_cbk (struct cli_state *state, struct cli_cmd_word *word,
+                       const char **words, int wordcount)
+{
+        int                    ret      = -1;
+        rpc_clnt_procedure_t  *proc     = NULL;
+        call_frame_t          *frame    = NULL;
+        char                  *filename = "";
+        dict_t                *dict     = NULL;
+        cli_local_t           *local    = NULL;
+
+        if (wordcount != 4) {
+                cli_usage_out (word->pattern);
+                goto out;
+        }
+
+        dict = dict_new ();
+        if (!dict)
+                goto out;
+
+        filename = (char*)words[3];
+        ret = dict_set_str (dict, "source", filename);
+        if (ret)
+                 gf_log ("", GF_LOG_ERROR, "Unable to set filename in dict");
+
+        ret = dict_set_str (dict, "volname", "N/A");
+        if (ret)
+                 gf_log ("", GF_LOG_ERROR, "Unable to set volname in dict");
+
+        proc = &cli_rpc_prog->proctable[GLUSTER_CLI_COPY_FILE];
+        if (proc && proc->fn) {
+                frame = create_frame (THIS, THIS->ctx->pool);
+                if (!frame)
+                        goto out;
+                CLI_LOCAL_INIT (local, words, frame, dict);
+                ret = proc->fn (frame, THIS, (void*)dict);
+        }
+out:
+        return ret;
+}
+
+int
 cli_cmd_system_help_cbk (struct cli_state *state, struct cli_cmd_word *in_word,
                          const char **words, int wordcount)
 {
diff --git a/cli/src/cli-cmd-volume-bdevice.c b/cli/src/cli-cmd-volume-bdevice.c
deleted file mode 100644
index 19325754f..000000000
--- a/cli/src/cli-cmd-volume-bdevice.c
+++ /dev/null
@@ -1,270 +0,0 @@
-/*
-  CLI for BD translator
-
-  Copyright IBM, Corp. 2012
-
-  This file is part of GlusterFS.
-
-  Author:
-  M. Mohan Kumar <mohan@in.ibm.com>
-
-  This file is licensed to you under your choice of the GNU Lesser
-  General Public License, version 3 or any later version (LGPLv3 or
-  later), or the GNU General Public License, version 2 (GPLv2), in all
-  cases as published by the Free Software Foundation.
-*/
-
-#ifndef _CONFIG_H
-#define _CONFIG_H
-#include "config.h"
-#endif
-
-#include "cli.h"
-#include "cli-cmd.h"
-#include <string.h>
-
-extern rpc_clnt_prog_t *cli_rpc_prog;
-
-int
-cli_cmd_bd_help_cbk (struct cli_state *state, struct cli_cmd_word *in_word,
-                      const char **words, int wordcount);
-
-int32_t
-cli_cmd_bd_parse (dict_t *dict, const char **words)
-{
-        char          *volname  = NULL;
-        char          *buff     = NULL;
-        char          *buffp    = NULL;
-        int            ret      = -1;
-        char          *save     = NULL;
-        char          *path     = NULL;
-        char          *size     = NULL;
-        char          *eptr     = NULL;
-        gf_xl_bd_op_t  bd_op    = GF_BD_OP_INVALID;
-        char          *dest_lv  = NULL;
-
-
-        /* volname:/path */
-        if (!strchr (words[2], ':') || !strchr (words[2], '/')) {
-                cli_out ("invalid parameter %s, needs <volname:/path>",
-                                words[2]);
-                return -1;
-        }
-        buff = buffp = gf_strdup (words[2]);
-        volname = strtok_r (buff, ":", &save);
-        path = strtok_r (NULL, ":", &save);
-
-        ret = dict_set_dynstr (dict, "volname", gf_strdup (volname));
-        if (ret)
-                goto out;
-
-        ret = dict_set_dynstr (dict, "path", gf_strdup (path));
-        if (ret)
-                goto out;
-
-        if (!strcasecmp (words[1], "create"))
-                bd_op = GF_BD_OP_NEW_BD;
-        else if (!strcasecmp (words[1], "delete"))
-                bd_op = GF_BD_OP_DELETE_BD;
-        else if (!strcasecmp (words[1], "clone"))
-                bd_op = GF_BD_OP_CLONE_BD;
-        else if (!strcasecmp (words[1], "snapshot"))
-                bd_op = GF_BD_OP_SNAPSHOT_BD;
-        else
-                return -1;
-
-        ret = dict_set_int32 (dict, "bd-op", bd_op);
-        if (ret)
-                goto out;
-
-        if (bd_op == GF_BD_OP_NEW_BD) {
-                /* If no suffix given we will treat it as MB */
-                strtoull (words[3], &eptr, 0);
-                /* no suffix */
-                if (!eptr[0])
-                        gf_asprintf (&size, "%sMB", words[3]);
-                else
-                        size = gf_strdup (words[3]);
-
-                ret = dict_set_dynstr (dict, "size", size);
-                if (ret)
-                        goto out;
-        } else if (bd_op == GF_BD_OP_SNAPSHOT_BD ||
-                   bd_op == GF_BD_OP_CLONE_BD) {
-                /*
-                 * dest_lv should be just dest_lv, we don't support
-                 * cloning/snapshotting to a different volume or vg
-                 */
-                if (strchr (words[3], ':') || strchr (words[3], '/')) {
-                        cli_err ("invalid parameter %s, volname/vg not needed",
-                                 words[3]);
-                        ret = -1;
-                        goto out;
-                }
-                dest_lv = gf_strdup (words[3]);
-                ret = dict_set_dynstr (dict, "dest_lv", dest_lv);
-                if (ret)
-                        goto out;
-
-                /* clone needs size as parameter */
-                if (bd_op == GF_BD_OP_SNAPSHOT_BD) {
-                        ret = dict_set_dynstr (dict, "size",
-                                               gf_strdup (words[4]));
-                        if (ret)
-                                goto out;
-                }
-        }
-
-        ret = 0;
-out:
-        GF_FREE (buffp);
-        return ret;
-}
-
-/*
- * bd create <volname>:/path <size>
- * bd delete <volname>:/path
- * bd clone <volname>:/path <newbd>
- * bd snapshot <volname>:/<path> <newbd> <size>
- */
-int32_t
-cli_cmd_bd_validate (const char **words, int wordcount, dict_t **options)
-{
-        dict_t  *dict = NULL;
-        int     ret   = -1;
-        char    *op[] = { "create", "delete", "clone", "snapshot", NULL };
-        int     index = 0;
-
-        for (index = 0; op[index]; index++)
-                if (!strcasecmp (words[1], op[index]))
-                        break;
-
-        if (!op[index])
-                return -1;
-
-        dict = dict_new ();
-        if (!dict)
-                goto out;
-
-        if (!strcasecmp (words[1], "create")) {
-                if (wordcount != 4)
-                        goto out;
-        } else if (!strcasecmp (words[1], "delete")) {
-                if (wordcount != 3)
-                        goto out;
-        } else if (!strcasecmp (words[1], "clone")) {
-                if (wordcount != 4)
-                        goto out;
-        } else if (!strcasecmp (words[1], "snapshot")) {
-                if (wordcount != 5)
-                        goto out;
-        } else {
-                ret = -1;
-                goto out;
-        }
-
-        ret = cli_cmd_bd_parse (dict, words);
-        if (ret < 0)
-                goto out;
-
-        *options = dict;
-        ret = 0;
-out:
-        if (ret)
-                dict_unref (dict);
-        return ret;
-}
-
-int
-cli_cmd_bd_cbk (struct cli_state *state, struct cli_cmd_word *word,
-                         const char **words, int wordcount)
-{
-        int                     ret         = -1;
-        rpc_clnt_procedure_t    *proc       = NULL;
-        call_frame_t            *frame      = NULL;
-        int                     sent        = 0;
-        int                     parse_error = 0;
-        dict_t                  *options    = NULL;
-        cli_local_t             *local = NULL;
-
-        proc = &cli_rpc_prog->proctable[GLUSTER_CLI_BD_OP];
-
-        frame = create_frame (THIS, THIS->ctx->pool);
-        if (!frame)
-                goto out;
-
-        ret = cli_cmd_bd_validate (words, wordcount, &options);
-        if (ret) {
-                cli_usage_out (word->pattern);
-                parse_error = 1;
-                goto out;
-        }
-
-        CLI_LOCAL_INIT (local, words, frame, options);
-        if (proc->fn) {
-                ret = proc->fn (frame, THIS, options);
-        }
-
-out:
-        if (options)
-                dict_unref (options);
-
-        if (ret) {
-                cli_cmd_sent_status_get (&sent);
-                if ((sent == 0) && (parse_error == 0))
-                        cli_out ("BD op failed!");
-        }
-
-        CLI_STACK_DESTROY (frame);
-
-        return ret;
-}
-
-struct cli_cmd cli_bd_cmds[] = {
-        { "bd help",
-           cli_cmd_bd_help_cbk,
-           "display help for bd command"},
-        { "bd create <volname>:<bd> <size>",
-          cli_cmd_bd_cbk,
-          "\n\tcreate a block device where size can be "
-          "suffixed with KB, MB etc. Default size is in MB"},
-        { "bd delete <volname>:<bd>",
-          cli_cmd_bd_cbk,
-          "Delete a block device"},
-        { "bd clone <volname>:<bd> <newbd>",
-          cli_cmd_bd_cbk,
-          "clone device"},
-        { "bd snapshot <volname>:<bd> <newbd> <size>",
-          cli_cmd_bd_cbk,
-          "\n\tsnapshot device where size can be "
-          "suffixed with KB, MB etc. Default size is in MB"},
-        { NULL, NULL, NULL }
-};
-
-int
-cli_cmd_bd_help_cbk (struct cli_state *state, struct cli_cmd_word *in_word,
-                      const char **words, int wordcount)
-{
-        struct cli_cmd *cmd = NULL;
-
-        for (cmd = cli_bd_cmds; cmd->pattern; cmd++)
-                if (_gf_false == cmd->disable)
-                        cli_out ("%s - %s", cmd->pattern, cmd->desc);
-
-        return 0;
-}
-
-int
-cli_cmd_bd_register (struct cli_state *state)
-{
-        int  ret = 0;
-        struct cli_cmd *cmd = NULL;
-
-        for (cmd = cli_bd_cmds; cmd->pattern; cmd++) {
-                ret = cli_cmd_register (&state->tree, cmd);
-                if (ret)
-                        goto out;
-        }
-out:
-        return ret;
-}
diff --git a/cli/src/cli-cmd-volume.c b/cli/src/cli-cmd-volume.c
index 4dcb99ce2..100be0b73 100644
--- a/cli/src/cli-cmd-volume.c
+++ b/cli/src/cli-cmd-volume.c
@@ -392,6 +392,15 @@ cli_cmd_volume_create_cbk (struct cli_state *state, struct cli_cmd_word *word,
                 }
         }
 
+        if (state->mode & GLUSTER_MODE_SCRIPT) {
+                ret = dict_set_int32 (options, "force", _gf_true);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to set force "
+                                "option");
+                        goto out;
+                }
+        }
+
         CLI_LOCAL_INIT (local, words, frame, options);
 
         if (proc->fn) {
@@ -888,6 +897,7 @@ cli_cmd_volume_set_cbk (struct cli_state *state, struct cli_cmd_word *word,
         call_frame_t            *frame = NULL;
         dict_t                  *options = NULL;
         cli_local_t             *local = NULL;
+        char                    *op_errstr = NULL;
 
         proc = &cli_rpc_prog->proctable[GLUSTER_CLI_SET_VOLUME];
 
@@ -895,9 +905,14 @@ cli_cmd_volume_set_cbk (struct cli_state *state, struct cli_cmd_word *word,
         if (!frame)
                 goto out;
 
-        ret = cli_cmd_volume_set_parse (words, wordcount, &options);
+        ret = cli_cmd_volume_set_parse (words, wordcount, &options, &op_errstr);
         if (ret) {
-                cli_usage_out (word->pattern);
+                if (op_errstr) {
+                    cli_err ("%s", op_errstr);
+                    GF_FREE (op_errstr);
+                } else
+                    cli_usage_out (word->pattern);
+
                 parse_error = 1;
                 goto out;
         }
@@ -963,6 +978,15 @@ cli_cmd_volume_add_brick_cbk (struct cli_state *state,
                 }
         }
 
+        if (state->mode & GLUSTER_MODE_SCRIPT) {
+                ret = dict_set_int32 (options, "force", _gf_true);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to set force "
+                                "option");
+                        goto out;
+                }
+        }
+
         proc = &cli_rpc_prog->proctable[GLUSTER_CLI_ADD_BRICK];
 
         CLI_LOCAL_INIT (local, words, frame, options);
@@ -1131,6 +1155,15 @@ cli_cmd_volume_replace_brick_cbk (struct cli_state *state,
                 goto out;
         }
 
+        if (state->mode & GLUSTER_MODE_SCRIPT) {
+                ret = dict_set_int32 (options, "force", _gf_true);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to set force"
+                                "option");
+                        goto out;
+                }
+        }
+
         CLI_LOCAL_INIT (local, words, frame, options);
 
         if (proc->fn) {
@@ -1795,7 +1828,13 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_info_cbk,
           "list information of all volumes"},
 
-        { "volume create <NEW-VOLNAME> [stripe <COUNT>] [replica <COUNT>] [device vg] [transport <tcp|rdma|tcp,rdma>] <NEW-BRICK> ...",
+        { "volume create <NEW-VOLNAME> [stripe <COUNT>] [replica <COUNT>] "
+          "[transport <tcp|rdma|tcp,rdma>] <NEW-BRICK>"
+#ifdef HAVE_BD_XLATOR
+          "?<vg_name>"
+#endif
+          "... [force]",
+
           cli_cmd_volume_create_cbk,
           "create a new volume of specified type with mentioned bricks"},
 
@@ -1815,11 +1854,11 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_rename_cbk,
           "rename volume <VOLNAME> to <NEW-VOLNAME>"},*/
 
-        { "volume add-brick <VOLNAME> [<stripe|replica> <COUNT>] <NEW-BRICK> ...",
+        { "volume add-brick <VOLNAME> [<stripe|replica> <COUNT>] <NEW-BRICK> ... [force]",
           cli_cmd_volume_add_brick_cbk,
           "add brick to volume <VOLNAME>"},
 
-        { "volume remove-brick <VOLNAME> [replica <COUNT>] <BRICK> ... {start|stop|status|commit|force}",
+        { "volume remove-brick <VOLNAME> [replica <COUNT>] <BRICK> ... [start|stop|status|commit|force]",
           cli_cmd_volume_remove_brick_cbk,
           "remove brick from volume <VOLNAME>"},
 
@@ -1827,7 +1866,7 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_volume_defrag_cbk,
           "rebalance operations"},
 
-        { "volume replace-brick <VOLNAME> <BRICK> <NEW-BRICK> {start|pause|abort|status|commit [force]}",
+        { "volume replace-brick <VOLNAME> <BRICK> <NEW-BRICK> {start [force]|pause|abort|status|commit [force]}",
           cli_cmd_volume_replace_brick_cbk,
           "replace-brick operations"},
 
@@ -1856,13 +1895,14 @@ struct cli_cmd volume_cmds[] = {
          "reset all the reconfigured options"},
 
 #if (SYNCDAEMON_COMPILE)
-        {"volume "GEOREP" [<VOLNAME>] [<SLAVE-URL>] {start|stop|config|status|log-rotate} [options...]",
+        {"volume "GEOREP" [<VOLNAME>] [<SLAVE-URL>] {create [push-pem] [force]"
+         "|start [force]|stop [force]|config|status [detail]|delete} [options...]",
          cli_cmd_volume_gsync_set_cbk,
          "Geo-sync operations",
          cli_cmd_check_gsync_exists_cbk},
 #endif
 
-         { "volume profile <VOLNAME> {start|info|stop} [nfs]",
+         { "volume profile <VOLNAME> {start|stop|info [nfs]}",
            cli_cmd_volume_profile_cbk,
            "volume profile operations"},
 
@@ -1870,18 +1910,17 @@ struct cli_cmd volume_cmds[] = {
           cli_cmd_quota_cbk,
           "quota translator specific operations"},
 
-         { "volume top <VOLNAME> {[open|read|write|opendir|readdir [nfs]] "
-           "|[read-perf|write-perf [nfs|{bs <size> count <count>}]]"
-           "|[clear [nfs]]} [brick <brick>] [list-cnt <count>]",
+         { "volume top <VOLNAME> {open|read|write|opendir|readdir|clear} [nfs|brick <brick>] [list-cnt <value>] |\n"
+           "volume top <VOLNAME> {read-perf|write-perf} [bs <size> count <count>] [brick <brick>] [list-cnt <value>]",
            cli_cmd_volume_top_cbk,
            "volume top operations"},
 
         { "volume status [all | <VOLNAME> [nfs|shd|<BRICK>]]"
-          " [detail|clients|mem|inode|fd|callpool]",
+          " [detail|clients|mem|inode|fd|callpool|tasks]",
           cli_cmd_volume_status_cbk,
           "display status of all or specified volume(s)/brick"},
 
-        { "volume heal <VOLNAME> [{full | info {healed | heal-failed | split-brain}}]",
+        { "volume heal <VOLNAME> [{full | statistics {heal-count {replica <hostname:brickname>}} |info {healed | heal-failed | split-brain}}]",
           cli_cmd_volume_heal_cbk,
           "self-heal commands on volume specified by <VOLNAME>"},
 
diff --git a/cli/src/cli-cmd.c b/cli/src/cli-cmd.c
index 7a697603e..b81f75b5b 100644
--- a/cli/src/cli-cmd.c
+++ b/cli/src/cli-cmd.c
@@ -231,11 +231,9 @@ cli_cmds_register (struct cli_state *state)
         if (ret)
                 goto out;
 
-#ifdef HAVE_BD_XLATOR
-        ret = cli_cmd_bd_register (state);
+        ret = cli_cmd_snapshot_register (state);
         if (ret)
                 goto out;
-#endif
 out:
         return ret;
 }
@@ -365,8 +363,11 @@ cli_cmd_submit (void *req, call_frame_t *frame,
         int             ret = -1;
         unsigned        timeout = 0;
 
-        timeout = (GLUSTER_CLI_PROFILE_VOLUME == procnum) ?
-                   CLI_TOP_CMD_TIMEOUT : CLI_DEFAULT_CMD_TIMEOUT;
+        if ((GLUSTER_CLI_PROFILE_VOLUME == procnum) ||
+            (GLUSTER_CLI_HEAL_VOLUME == procnum))
+                timeout = CLI_TEN_MINUTES_TIMEOUT;
+        else
+                timeout = CLI_DEFAULT_CMD_TIMEOUT;
 
         cli_cmd_lock ();
         cmd_sent = 0;
diff --git a/cli/src/cli-cmd.h b/cli/src/cli-cmd.h
index 0ad37d498..041729276 100644
--- a/cli/src/cli-cmd.h
+++ b/cli/src/cli-cmd.h
@@ -93,6 +93,8 @@ int cli_cmd_probe_register (struct cli_state *state);
 
 int cli_cmd_system_register (struct cli_state *state);
 
+int cli_cmd_snapshot_register (struct cli_state *state);
+
 int cli_cmd_misc_register (struct cli_state *state);
 
 struct cli_cmd_word *cli_cmd_nextword (struct cli_cmd_word *word,
@@ -119,7 +121,4 @@ gf_answer_t
 cli_cmd_get_confirmation (struct cli_state *state, const char *question);
 int cli_cmd_sent_status_get (int *status);
 
-#ifdef HAVE_BD_XLATOR
-int cli_cmd_bd_register (struct cli_state *state);
-#endif
 #endif /* __CLI_CMD_H__ */
diff --git a/cli/src/cli-rl.c b/cli/src/cli-rl.c
index 6f75b6f4c..ade1c8ebb 100644
--- a/cli/src/cli-rl.c
+++ b/cli/src/cli-rl.c
@@ -365,7 +365,8 @@ cli_rl_input (void *_data)
                 if (!line)
                         exit(0);  //break;
 
-                cli_rl_process_line (line);
+                if (*line)
+                        cli_rl_process_line (line);
 
                 free (line);
         }
diff --git a/cli/src/cli-rpc-ops.c b/cli/src/cli-rpc-ops.c
index da239b51e..bfeb854ad 100644
--- a/cli/src/cli-rpc-ops.c
+++ b/cli/src/cli-rpc-ops.c
@@ -13,10 +13,6 @@
 #include "config.h"
 #endif
 
-#ifndef GSYNC_CONF
-#define GSYNC_CONF GEOREP"/gsyncd.conf"
-#endif
-
 /* Widths of various columns in top read/write-perf output
  * Total width of top read/write-perf should be 80 chars
  * including one space between column
@@ -26,6 +22,8 @@
 #define VOL_TOP_PERF_SPEED_WIDTH        4
 #define VOL_TOP_PERF_TIME_WIDTH         26
 
+#define INDENT_MAIN_HEAD "%-25s %s "
+
 #include "cli.h"
 #include "compat-errno.h"
 #include "cli-cmd.h"
@@ -62,8 +60,15 @@ char *cli_vol_status_str[] = {"Created",
                               "Stopped",
                              };
 
-char *cli_volume_backend[] = {"",
-                           "Volume Group",
+char *cli_vol_task_status_str[] = {"not started",
+                                   "in progress",
+                                   "stopped",
+                                   "completed",
+                                   "failed",
+                                   "fix-layout in progress",
+                                   "fix-layout stopped",
+                                   "fix-layout completed",
+                                   "fix-layout failed",
 };
 
 int32_t
@@ -87,47 +92,11 @@ rpc_clnt_prog_t cli_pmap_prog = {
         .progver    = GLUSTER_PMAP_VERSION,
 };
 
-void
-gf_cli_probe_strerror (gf1_cli_probe_rsp *rsp, char *msg, size_t len)
-{
-        switch (rsp->op_errno) {
-        case GF_PROBE_ANOTHER_CLUSTER:
-                snprintf (msg, len, "%s is already part of another cluster",
-                          rsp->hostname);
-                break;
-        case GF_PROBE_VOLUME_CONFLICT:
-                snprintf (msg, len, "Atleast one volume on %s conflicts with "
-                          "existing volumes in the cluster", rsp->hostname);
-                break;
-        case GF_PROBE_UNKNOWN_PEER:
-                snprintf (msg, len, "%s responded with 'unknown peer' error, "
-                          "this could happen if %s doesn't have localhost in "
-                          "its peer database", rsp->hostname, rsp->hostname);
-                break;
-        case GF_PROBE_ADD_FAILED:
-                snprintf (msg, len, "Failed to add peer information on %s" ,
-                          rsp->hostname);
-                break;
-        case GF_PROBE_SAME_UUID:
-                snprintf (msg, len, "Peer uuid (host %s) is same as local uuid",
-                          rsp->hostname);
-                break;
-        case GF_PROBE_QUORUM_NOT_MET:
-                snprintf (msg, len, "Cluster quorum is not met. Changing "
-                          "peers is not allowed in this state");
-                break;
-        default:
-                snprintf (msg, len, "Probe returned with unknown "
-                          "errno %d", rsp->op_errno);
-                break;
-        }
-}
-
 int
 gf_cli_probe_cbk (struct rpc_req *req, struct iovec *iov,
                         int count, void *myframe)
 {
-        gf1_cli_probe_rsp     rsp   = {0,};
+        gf_cli_rsp            rsp   = {0,};
         int                   ret   = -1;
         char                  msg[1024] = {0,};
 
@@ -135,52 +104,28 @@ gf_cli_probe_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
-        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_probe_rsp);
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 //rsp.op_ret   = -1;
                 //rsp.op_errno = EINVAL;
                 goto out;
         }
 
         gf_log ("cli", GF_LOG_INFO, "Received resp to probe");
-         if (!rsp.op_ret) {
-                switch (rsp.op_errno) {
-                        case GF_PROBE_SUCCESS:
-                                snprintf (msg, sizeof (msg),
-                                          "success");
-                                break;
-                        case GF_PROBE_LOCALHOST:
-                                snprintf (msg, sizeof (msg),
-                                          "success: on localhost not needed");
-                                break;
-                        case GF_PROBE_FRIEND:
-                                snprintf (msg, sizeof (msg),
-                                          "success: host %s port %d already"
-                                          " in peer list", rsp.hostname,
-                                          rsp.port);
-                                break;
-                        default:
-                                rsp.op_ret = -1;
-                                snprintf (msg, sizeof (msg),
-                                          "Probe returned with unknown errno"
-                                          " %d", rsp.op_errno);
-                                break;
-                }
-         }
 
-        if (rsp.op_ret) {
-                if (rsp.op_errstr && (strlen (rsp.op_errstr) > 0)) {
-                        snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
-                } else {
-                        gf_cli_probe_strerror (&rsp, msg, sizeof (msg));
-                }
-                gf_log ("cli", GF_LOG_ERROR, "%s", msg);
+        if (rsp.op_errstr && (strlen (rsp.op_errstr) > 0)) {
+                snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
+                if (rsp.op_ret)
+                        gf_log ("cli", GF_LOG_ERROR, "%s", msg);
         }
 
         if (global_state->mode & GLUSTER_MODE_XML) {
-                ret = cli_xml_output_str ("peerProbe", msg, rsp.op_ret,
-                                          rsp.op_errno, NULL);
+                ret = cli_xml_output_str (NULL,
+                                          (rsp.op_ret)? NULL : msg,
+                                          rsp.op_ret, rsp.op_errno,
+                                          (rsp.op_ret)? msg : NULL);
                 if (ret)
                         gf_log ("cli", GF_LOG_ERROR,
                                 "Error outputting to xml");
@@ -188,7 +133,7 @@ gf_cli_probe_cbk (struct rpc_req *req, struct iovec *iov,
         }
 
         if (!rsp.op_ret)
-                cli_out ("peer probe: %s", msg);
+                cli_out ("peer probe: success. %s", msg);
         else
                 cli_err ("peer probe: failed: %s", msg);
 
@@ -203,73 +148,39 @@ int
 gf_cli_deprobe_cbk (struct rpc_req *req, struct iovec *iov,
                        int count, void *myframe)
 {
-        gf1_cli_deprobe_rsp    rsp   = {0,};
+        gf_cli_rsp            rsp   = {0,};
         int                   ret   = -1;
-        char                  msg[1024] = {0,};
+        char              msg[1024] = {0,};
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
-        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_deprobe_rsp);
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 //rsp.op_ret   = -1;
                 //rsp.op_errno = EINVAL;
                 goto out;
         }
 
         gf_log ("cli", GF_LOG_INFO, "Received resp to deprobe");
+
         if (rsp.op_ret) {
                 if (strlen (rsp.op_errstr) > 0) {
                         snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
                         gf_log ("cli", GF_LOG_ERROR, "%s", rsp.op_errstr);
-                } else {
-                        switch (rsp.op_errno) {
-                                case GF_DEPROBE_LOCALHOST:
-                                        snprintf (msg, sizeof (msg),
-                                                  "%s is localhost",
-                                                  rsp.hostname);
-                                        break;
-                                case GF_DEPROBE_NOT_FRIEND:
-                                        snprintf (msg, sizeof (msg),
-                                                  "%s is not part of cluster",
-                                                  rsp.hostname);
-                                        break;
-                                case GF_DEPROBE_BRICK_EXIST:
-                                        snprintf (msg, sizeof (msg),
-                                                  "Brick(s) with the peer %s "
-                                                  "exist in cluster",
-                                                  rsp.hostname);
-                                        break;
-                                case GF_DEPROBE_FRIEND_DOWN:
-                                        snprintf (msg, sizeof (msg),
-                                                  "One of the peers is probably"
-                                                  " down. Check with 'peer "
-                                                  "status'.");
-                                        break;
-                                case GF_DEPROBE_QUORUM_NOT_MET:
-                                        snprintf (msg, sizeof (msg), "Cluster "
-                                                  "quorum is not met. Changing "
-                                                  "peers is not allowed in this"
-                                                  " state");
-                                        break;
-                                default:
-                                        snprintf (msg, sizeof (msg),
-                                                  "Detach returned with unknown"
-                                                  " errno %d", rsp.op_errno);
-                                        break;
-                        }
-                        gf_log ("cli", GF_LOG_ERROR,"Detach failed with op_ret "
-                                "%d and op_errno %d", rsp.op_ret, rsp.op_errno);
                 }
         } else {
                 snprintf (msg, sizeof (msg), "success");
         }
 
         if (global_state->mode & GLUSTER_MODE_XML) {
-                ret = cli_xml_output_str ("peerDetach", msg, rsp.op_ret,
-                                          rsp.op_errno, NULL);
+                ret = cli_xml_output_str (NULL,
+                                          (rsp.op_ret)? NULL : msg,
+                                          rsp.op_ret, rsp.op_errno,
+                                          (rsp.op_ret)? msg : NULL);
                 if (ret)
                         gf_log ("cli", GF_LOG_ERROR,
                                 "Error outputting to xml");
@@ -289,21 +200,128 @@ out:
 }
 
 int
-gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
-                             int count, void *myframe)
+gf_cli_output_peer_status (dict_t *dict, int count)
 {
-        gf1_cli_peer_list_rsp      rsp   = {0,};
         int                        ret   = -1;
-        dict_t                     *dict = NULL;
         char                       *uuid_buf = NULL;
         char                       *hostname_buf = NULL;
         int32_t                    i = 1;
         char                       key[256] = {0,};
         char                       *state = NULL;
-        int32_t                    port = 0;
         int32_t                    connected = 0;
         char                       *connected_str = NULL;
+
+        cli_out ("Number of Peers: %d", count);
+        i = 1;
+        while ( i <= count) {
+                snprintf (key, 256, "friend%d.uuid", i);
+                ret = dict_get_str (dict, key, &uuid_buf);
+                if (ret)
+                        goto out;
+
+                snprintf (key, 256, "friend%d.hostname", i);
+                ret = dict_get_str (dict, key, &hostname_buf);
+                if (ret)
+                        goto out;
+
+                snprintf (key, 256, "friend%d.connected", i);
+                ret = dict_get_int32 (dict, key, &connected);
+                if (ret)
+                        goto out;
+                if (connected)
+                        connected_str = "Connected";
+                else
+                        connected_str = "Disconnected";
+
+
+                snprintf (key, 256, "friend%d.state", i);
+                ret = dict_get_str (dict, key, &state);
+                if (ret)
+                        goto out;
+
+                cli_out ("\nHostname: %s\nUuid: %s\nState: %s (%s)",
+                         hostname_buf, uuid_buf, state, connected_str);
+                i++;
+        }
+
+        ret = 0;
+out:
+        return ret;
+}
+
+int
+gf_cli_output_pool_list (dict_t *dict, int count)
+{
+        int                        ret   = -1;
+        char                       *uuid_buf = NULL;
+        char                       *hostname_buf = NULL;
+        int32_t                    i = 1;
+        char                       key[256] = {0,};
+        int32_t                    connected = 0;
+        char                       *connected_str = NULL;
+
+        if (count >= 1)
+                cli_out ("UUID\t\t\t\t\tHostname\tState");
+
+        while ( i <= count) {
+                snprintf (key, 256, "friend%d.uuid", i);
+                ret = dict_get_str (dict, key, &uuid_buf);
+                if (ret)
+                        goto out;
+
+                snprintf (key, 256, "friend%d.hostname", i);
+                ret = dict_get_str (dict, key, &hostname_buf);
+                if (ret)
+                        goto out;
+
+                snprintf (key, 256, "friend%d.connected", i);
+                ret = dict_get_int32 (dict, key, &connected);
+                if (ret)
+                        goto out;
+                if (connected)
+                        connected_str = "Connected";
+                else
+                        connected_str = "Disconnected";
+
+                cli_out ("%s\t%-9s\t%s ", uuid_buf, hostname_buf,
+                         connected_str);
+                i++;
+        }
+
+        ret = 0;
+out:
+        return ret;
+}
+
+/* function pointer for gf_cli_output_{pool_list,peer_status} */
+typedef int (*cli_friend_output_fn) (dict_t*, int);
+
+int
+gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
+                             int count, void *myframe)
+{
+        gf1_cli_peer_list_rsp      rsp   = {0,};
+        int                        ret   = -1;
+        dict_t                    *dict = NULL;
         char                       msg[1024] = {0,};
+        char                      *cmd = NULL;
+        cli_friend_output_fn       friend_output_fn;
+        call_frame_t              *frame = NULL;
+        unsigned long              flags = 0;
+
+        frame = myframe;
+        flags = (long)frame->local;
+
+        if (flags == GF_CLI_LIST_POOL_NODES) {
+                cmd = "pool list";
+                friend_output_fn = &gf_cli_output_pool_list;
+        } else {
+                cmd = "peer status";
+                friend_output_fn = &gf_cli_output_peer_status;
+        }
+
+        /* 'free' the flags set by gf_cli_list_friends */
+        frame->local = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
@@ -311,13 +329,14 @@ gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_peer_list_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 //rsp.op_ret   = -1;
                 //rsp.op_errno = EINVAL;
                 goto out;
         }
 
-        gf_log ("cli", GF_LOG_INFO, "Received resp to list: %d",
+        gf_log ("cli", GF_LOG_DEBUG, "Received resp to list: %d",
                 rsp.op_ret);
 
         ret = rsp.op_ret;
@@ -326,7 +345,7 @@ gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
 
                 if (!rsp.friends.friends_len) {
                         snprintf (msg, sizeof (msg),
-                                  "peer status: No peers present");
+                                  "%s: No peers present", cmd);
                         if (global_state->mode & GLUSTER_MODE_XML) {
                                 ret = cli_xml_output_peer_status (dict,
                                                                   rsp.op_ret,
@@ -373,49 +392,9 @@ gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
                         goto out;
                 }
 
-                cli_out ("Number of Peers: %d", count);
-                i = 1;
-                while ( i <= count) {
-                        snprintf (key, 256, "friend%d.uuid", i);
-                        ret = dict_get_str (dict, key, &uuid_buf);
-                        if (ret)
-                                goto out;
-
-                        snprintf (key, 256, "friend%d.hostname", i);
-                        ret = dict_get_str (dict, key, &hostname_buf);
-                        if (ret)
-                                goto out;
-
-                        snprintf (key, 256, "friend%d.connected", i);
-                        ret = dict_get_int32 (dict, key, &connected);
-                        if (ret)
-                                goto out;
-                        if (connected)
-                                connected_str = "Connected";
-                        else
-                                connected_str = "Disconnected";
-
-                        snprintf (key, 256, "friend%d.port", i);
-                        ret = dict_get_int32 (dict, key, &port);
-                        if (ret)
-                                goto out;
-
-                        snprintf (key, 256, "friend%d.state", i);
-                        ret = dict_get_str (dict, key, &state);
-                        if (ret)
-                                goto out;
-
-                        if (!port) {
-                                cli_out ("\nHostname: %s\nUuid: %s\nState: %s "
-                                         "(%s)",
-                                         hostname_buf, uuid_buf, state,
-                                         connected_str);
-                        } else {
-                                cli_out ("\nHostname: %s\nPort: %d\nUuid: %s\n"
-                                         "State: %s (%s)", hostname_buf, port,
-                                         uuid_buf, state, connected_str);
-                        }
-                        i++;
+                ret = friend_output_fn (dict, count);
+                if (ret) {
+                        goto out;
                 }
         } else {
                 if (global_state->mode & GLUSTER_MODE_XML) {
@@ -436,7 +415,7 @@ gf_cli_list_friends_cbk (struct rpc_req *req, struct iovec *iov,
 out:
         cli_cmd_broadcast_response (ret);
         if (ret)
-                cli_err ("peer status: failed");
+                cli_err ("%s: failed", cmd);
 
         if (dict)
                 dict_destroy (dict);
@@ -470,6 +449,30 @@ cli_out_options ( char *substr, char *optstr, char *valstr)
         cli_out ("%s: %s",ptr2 , valstr);
 }
 
+static int
+_gf_cli_output_volinfo_opts (dict_t *d, char *k,
+                             data_t *v, void *tmp)
+{
+        int     ret   = 0;
+        char   *key   = NULL;
+        char   *ptr   = NULL;
+        data_t *value = NULL;
+
+        key = tmp;
+
+        ptr = strstr (k, "option.");
+        if (ptr) {
+                value = v;
+                if (!value) {
+                        ret = -1;
+                        goto out;
+                }
+                cli_out_options (key, k, v->data);
+        }
+out:
+        return ret;
+}
+
 
 int
 gf_cli_get_volume_cbk (struct rpc_req *req, struct iovec *iov,
@@ -487,24 +490,27 @@ gf_cli_get_volume_cbk (struct rpc_req *req, struct iovec *iov,
         int32_t                    replica_count        = 0;
         int32_t                    vol_type             = 0;
         int32_t                    transport            = 0;
-        char                      *ptr                  = NULL;
         char                      *volume_id_str        = NULL;
         char                      *brick                = NULL;
         char                      *volname              = NULL;
         dict_t                    *dict                 = NULL;
-        data_t                    *value                = NULL;
         cli_local_t               *local                = NULL;
         char                       key[1024]            = {0};
         char                       err_str[2048]        = {0};
         gf_cli_rsp                 rsp                  = {0};
-        int32_t                    backend              = 0;
+        char                      *caps                 = NULL;
+        int                        k __attribute__((unused)) = 0;
+        // snap_volume variable helps in showing whether a volume is a normal
+        //volume or a volume for the snapshot
+        int32_t                    snap_volume          = 0;
 
         if (-1 == req->rpc_status)
                 goto out;
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("cli", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -618,6 +624,11 @@ xml_output:
                 if (ret)
                         goto out;
 
+                snprintf (key, sizeof (key), "volume%d.snap_volume", i);
+                ret = dict_get_int32 (dict, key, &snap_volume);
+                if (ret)
+                        goto out;
+
                 snprintf (key, 256, "volume%d.brick_count", i);
                 ret = dict_get_int32 (dict, key, &brick_count);
                 if (ret)
@@ -648,9 +659,6 @@ xml_output:
                 if (ret)
                         goto out;
 
-                snprintf (key, 256, "volume%d.backend", i);
-                ret = dict_get_int32 (dict, key, &backend);
-
                 vol_type = type;
 
                 // Distributed (stripe/replicate/stripe-replica) setups
@@ -661,9 +669,44 @@ xml_output:
                 cli_out ("Type: %s", cli_vol_type_str[vol_type]);
                 cli_out ("Volume ID: %s", volume_id_str);
                 cli_out ("Status: %s", cli_vol_status_str[status]);
+                if (snap_volume)
+                        cli_out ("Snap Volume: %s", "yes");
+                else
+                        cli_out ("Snap Volume: %s", "no");
 
-                if (backend)
+#ifdef HAVE_BD_XLATOR
+                k = 0;
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "volume%d.xlator%d", i, k);
+                ret = dict_get_str (dict, key, &caps);
+                if (ret)
                         goto next;
+                do {
+                        j = 0;
+                        cli_out ("Xlator %d: %s", k + 1, caps);
+                        do {
+                                memset (key, 0, sizeof (key));
+                                snprintf (key, sizeof (key),
+                                          "volume%d.xlator%d.caps%d",
+                                          i, k, j++);
+                                ret = dict_get_str (dict, key, &caps);
+                                if (ret)
+                                        break;
+                                cli_out ("Capability %d: %s", j, caps);
+                        } while (1);
+
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key),
+                                  "volume%d.xlator%d", i, ++k);
+                        ret = dict_get_str (dict, key, &caps);
+                        if (ret)
+                                break;
+                } while (1);
+
+next:
+#else
+                caps = 0; /* Avoid compiler warnings when BD not enabled */
+#endif
 
                 if (type == GF_CLUSTER_TYPE_STRIPE_REPLICATE) {
                         cli_out ("Number of Bricks: %d x %d x %d = %d",
@@ -685,12 +728,6 @@ xml_output:
                          ((transport == 0)?"tcp":
                           (transport == 1)?"rdma":
                           "tcp,rdma"));
-
-next:
-                if (backend) {
-                        cli_out ("Backend Type: Block, %s",
-                                 cli_volume_backend[backend]);
-                }
                 j = 1;
 
                 GF_FREE (local->get_vol.volname);
@@ -706,6 +743,12 @@ next:
                                 goto out;
 
                         cli_out ("Brick%d: %s", j, brick);
+#ifdef HAVE_BD_XLATOR
+                        snprintf (key, 256, "volume%d.vg%d", i, j);
+                        ret = dict_get_str (dict, key, &caps);
+                        if (!ret)
+                                cli_out ("Brick%d VG: %s", j, caps);
+#endif
                         j++;
                 }
 
@@ -720,22 +763,8 @@ next:
                 cli_out ("Options Reconfigured:");
 
                 snprintf (key, 256, "volume%d.option.",i);
-                int _output_volinfo_opts (dict_t *d, char *k,
-                                          data_t *v, void *tmp)
-                {
-                        ptr = strstr (k, "option.");
-                        if (ptr) {
-                                value = v;
-                                if (!value) {
-                                        ret = -1;
-                                        goto internal_out;
-                                }
-                                cli_out_options (key, k, v->data);
-                        }
-                internal_out:
-                        return ret;
-                }
-                ret = dict_foreach (dict, _output_volinfo_opts, NULL);
+
+                ret = dict_foreach (dict, _gf_cli_output_volinfo_opts, key);
                 if (ret)
                         goto out;
 
@@ -779,7 +808,8 @@ gf_cli_create_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -846,20 +876,22 @@ gf_cli_delete_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
         local = frame->local;
 
         if (local)
                 dict = local->dict;
         ret = dict_get_str (dict, "volname", &volname);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR,
+                gf_log (frame->this->name, GF_LOG_ERROR,
                         "dict get failed");
                 goto out;
         }
@@ -907,6 +939,88 @@ out:
 }
 
 int
+gf_cli3_1_uuid_get_cbk (struct rpc_req *req, struct iovec *iov,
+                        int count, void *myframe)
+{
+        char                    *uuid_str = NULL;
+        gf_cli_rsp              rsp   = {0,};
+        int                     ret   = -1;
+        cli_local_t             *local = NULL;
+        call_frame_t            *frame = NULL;
+        dict_t                  *dict = NULL;
+
+        if (-1 == req->rpc_status)
+                goto out;
+
+        frame = myframe;
+
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        local = frame->local;
+        frame->local = NULL;
+
+        gf_log ("cli", GF_LOG_INFO, "Received resp to uuid get");
+
+        dict = dict_new ();
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len,
+                                &dict);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to unserialize "
+                        "response for uuid get");
+                goto out;
+        }
+
+        ret = dict_get_str (dict, "uuid", &uuid_str);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to get uuid "
+                        "from dictionary");
+                goto out;
+        }
+
+        if (global_state->mode & GLUSTER_MODE_XML) {
+                ret = cli_xml_output_dict ("uuidGenerate", dict, rsp.op_ret,
+                                           rsp.op_errno, rsp.op_errstr);
+                if (ret)
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Error outputting to xml");
+                goto out;
+        }
+
+        if (rsp.op_ret) {
+                if (strcmp (rsp.op_errstr, "") == 0)
+                        cli_err ("Get uuid was unsuccessful");
+                else
+                        cli_err ("%s", rsp.op_errstr);
+
+        } else {
+                cli_out ("UUID: %s", uuid_str);
+
+        }
+        ret = rsp.op_ret;
+
+out:
+        cli_cmd_broadcast_response (ret);
+        cli_local_wipe (local);
+        if (rsp.dict.dict_val)
+                free (rsp.dict.dict_val);
+        if (dict)
+                dict_unref (dict);
+
+        gf_log ("", GF_LOG_DEBUG, "Returning with %d", ret);
+        return ret;
+}
+
+int
 gf_cli3_1_uuid_reset_cbk (struct rpc_req *req, struct iovec *iov,
                              int count, void *myframe)
 {
@@ -920,13 +1034,15 @@ gf_cli3_1_uuid_reset_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
         local = frame->local;
         frame->local = NULL;
 
@@ -976,14 +1092,15 @@ gf_cli_start_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
-
         if (frame)
                 local = frame->local;
 
@@ -992,7 +1109,7 @@ gf_cli_start_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_str (dict, "volname", &volname);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "dict get failed");
+                gf_log (frame->this->name, GF_LOG_ERROR, "dict get failed");
                 goto out;
         }
 
@@ -1053,14 +1170,15 @@ gf_cli_stop_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
-
         if (frame)
                 local = frame->local;
 
@@ -1068,7 +1186,7 @@ gf_cli_stop_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 dict = local->dict;
                 ret = dict_get_str (dict, "volname", &volname);
                 if (ret) {
-                        gf_log (THIS->name, GF_LOG_ERROR,
+                        gf_log (frame->this->name, GF_LOG_ERROR,
                                 "Unable to get volname from dict");
                         goto out;
                 }
@@ -1134,26 +1252,29 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
         char                     msg[1024] = {0,};
         gf_defrag_status_t       status_rcd = GF_DEFRAG_STATUS_NOT_STARTED;
         int32_t                  counter = 0;
-        char                    *node_uuid = NULL;
+        char                    *node_name = NULL;
         char                     key[256] = {0,};
         int32_t                  i = 1;
         uint64_t                 failures = 0;
+        uint64_t                 skipped = 0;
         double                   elapsed = 0;
         char                    *size_str = NULL;
+        char                    *task_id_str = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp,
                               (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
-
         if (frame)
                 local = frame->local;
 
@@ -1162,14 +1283,14 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_str (local_dict, "volname", &volname);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR,
+                gf_log (frame->this->name, GF_LOG_ERROR,
                         "Failed to get volname");
                 goto out;
         }
 
         ret = dict_get_int32 (local_dict, "rebalance-command", (int32_t*)&cmd);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR,
+                gf_log (frame->this->name, GF_LOG_ERROR,
                         "Failed to get command");
                 goto out;
         }
@@ -1189,15 +1310,24 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 }
         }
 
-        if (!((cmd == GF_DEFRAG_CMD_STOP) || (cmd == GF_DEFRAG_CMD_STATUS))) {
-                /* All other possibility is about starting a volume */
-                if (rsp.op_ret && strcmp (rsp.op_errstr, ""))
+        if (!((cmd == GF_DEFRAG_CMD_STOP) || (cmd == GF_DEFRAG_CMD_STATUS)) &&
+             !(global_state->mode & GLUSTER_MODE_XML)) {
+                /* All other possibilites are about starting a rebalance */
+                ret = dict_get_str (dict, GF_REBALANCE_TID_KEY, &task_id_str);
+                if (rsp.op_ret && strcmp (rsp.op_errstr, "")) {
                         snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
-                else
-                        snprintf (msg, sizeof (msg),
-                                  "Starting rebalance on volume %s has been %s",
-                                  volname, (rsp.op_ret) ? "unsuccessful":
-                                  "successful");
+                } else {
+                        if (!rsp.op_ret) {
+                                snprintf (msg, sizeof (msg),
+                                          "Starting rebalance on volume %s has "
+                                          "been successful.\nID: %s", volname,
+                                          task_id_str);
+                        } else {
+                                snprintf (msg, sizeof (msg),
+                                          "Starting rebalance on volume %s has "
+                                          "been unsuccessful.", volname);
+                        }
+                }
                 goto done;
         }
 
@@ -1213,8 +1343,12 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
                         goto done;
                 } else {
                         snprintf (msg, sizeof (msg),
-                                 "Stopped rebalance process on volume %s \n",
-                                  volname);
+                                  "rebalance process may be in the middle of a "
+                                  "file migration.\nThe process will be fully "
+                                  "stopped once the migration of the file is "
+                                  "complete.\nPlease check rebalance process "
+                                  "for completion before doing any further "
+                                  "brick related tasks on the volume.");
                 }
         }
         if (cmd == GF_DEFRAG_CMD_STATUS) {
@@ -1239,86 +1373,76 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_int32 (dict, "count", &counter);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "count not set");
+                gf_log (frame->this->name, GF_LOG_ERROR, "count not set");
                 goto out;
         }
 
-        cli_out ("%40s %16s %13s %13s %13s %14s %s", "Node", "Rebalanced-files",
-                 "size", "scanned", "failures", "status", "run time in secs");
-        cli_out ("%40s %16s %13s %13s %13s %14s %16s", "---------",
+        cli_out ("%40s %16s %13s %13s %13s %13s %20s %18s", "Node",
+                 "Rebalanced-files", "size", "scanned", "failures", "skipped",
+                 "status", "run time in secs");
+        cli_out ("%40s %16s %13s %13s %13s %13s %20s %18s", "---------",
                  "-----------", "-----------", "-----------", "-----------",
-                 "------------", "--------------");
+                 "-----------", "------------", "--------------");
         do {
-                snprintf (key, 256, "node-uuid-%d", i);
-                ret = dict_get_str (dict, key, &node_uuid);
+                snprintf (key, 256, "node-name-%d", i);
+                ret = dict_get_str (dict, key, &node_name);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
-                                "failed to get node-uuid");
+                        gf_log (frame->this->name, GF_LOG_TRACE,
+                                "failed to get node-name");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "files-%d", i);
                 ret = dict_get_uint64 (dict, key, &files);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get file count");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "size-%d", i);
                 ret = dict_get_uint64 (dict, key, &size);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get size of xfer");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "lookups-%d", i);
                 ret = dict_get_uint64 (dict, key, &lookup);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get lookedup file count");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "status-%d", i);
                 ret = dict_get_int32 (dict, key, (int32_t *)&status_rcd);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get status");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "failures-%d", i);
                 ret = dict_get_uint64 (dict, key, &failures);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get failures count");
 
                 memset (key, 0, 256);
+                snprintf (key, 256, "skipped-%d", i);
+                ret = dict_get_uint64 (dict, key, &skipped);
+                if (ret)
+                        gf_log (frame->this->name, GF_LOG_TRACE,
+                                "failed to get skipped count");
+                memset (key, 0, 256);
                 snprintf (key, 256, "run-time-%d", i);
                 ret = dict_get_double (dict, key, &elapsed);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get run-time");
 
-                switch (status_rcd) {
-                case GF_DEFRAG_STATUS_NOT_STARTED:
-                        status = "not started";
-                        break;
-                case GF_DEFRAG_STATUS_STARTED:
-                        status = "in progress";
-                        break;
-                case GF_DEFRAG_STATUS_STOPPED:
-                        status = "stopped";
-                        break;
-                case GF_DEFRAG_STATUS_COMPLETE:
-                        status = "completed";
-                        break;
-                case GF_DEFRAG_STATUS_FAILED:
-                        status = "failed";
-                        break;
-                }
-
+                status = cli_vol_task_status_str[status_rcd];
                 size_str = gf_uint64_2human_readable(size);
                 cli_out ("%40s %16"PRIu64 " %13s" " %13"PRIu64 " %13"PRIu64
-                         " %14s %16.2f", node_uuid, files, size_str, lookup,
-                         failures, status, elapsed);
+                         " %13"PRIu64 " %20s %18.2f", node_name, files,
+                         size_str, lookup, failures, skipped, status, elapsed);
                 GF_FREE(size_str);
 
                 i++;
@@ -1326,10 +1450,18 @@ gf_cli_defrag_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
 
 done:
-        if (rsp.op_ret)
-                cli_err ("volume rebalance: %s: failed: %s", volname, msg);
-        else
-                cli_out ("volume rebalance: %s: success: %s", volname, msg);
+        if (global_state->mode & GLUSTER_MODE_XML)
+                cli_xml_output_str ("volRebalance", msg,
+                                    rsp.op_ret, rsp.op_errno,
+                                    rsp.op_errstr);
+        else {
+                if (rsp.op_ret)
+                        cli_err ("volume rebalance: %s: failed: %s", volname,
+                                 msg);
+                else
+                        cli_out ("volume rebalance: %s: success: %s", volname,
+                                 msg);
+        }
         ret = rsp.op_ret;
 
 out:
@@ -1355,7 +1487,8 @@ gf_cli_rename_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -1399,13 +1532,14 @@ gf_cli_reset_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
         gf_log ("cli", GF_LOG_INFO, "Received resp to reset");
 
-        if (rsp.op_ret &&  strcmp (rsp.op_errstr, ""))
+        if (strcmp (rsp.op_errstr, ""))
                 snprintf (msg, sizeof (msg), "%s", rsp.op_errstr);
         else
                 snprintf (msg, sizeof (msg), "reset volume %s",
@@ -1423,7 +1557,7 @@ gf_cli_reset_volume_cbk (struct rpc_req *req, struct iovec *iov,
         if (rsp.op_ret)
                 cli_err ("volume reset: failed: %s", msg);
         else
-                cli_out ("volume reset: success");
+                cli_out ("volume reset: success: %s", msg);
 
         ret = rsp.op_ret;
 
@@ -1432,6 +1566,53 @@ out:
         return ret;
 }
 
+char *
+is_server_debug_xlator (void *myframe)
+{
+        call_frame_t         *frame        = NULL;
+        cli_local_t          *local        = NULL;
+        char                 **words       = NULL;
+        char                 *key          = NULL;
+        char                 *value        = NULL;
+        char                 *debug_xlator = NULL;
+
+        frame = myframe;
+        local = frame->local;
+        words = (char **)local->words;
+
+        while (*words != NULL) {
+                if (strstr (*words, "trace") == NULL &&
+                    strstr (*words, "error-gen") == NULL) {
+                        words++;
+                        continue;
+                }
+
+                key = *words;
+                words++;
+                value = *words;
+                if (value == NULL)
+                        break;
+                if (strstr (value, "client")) {
+                        words++;
+                        continue;
+                } else {
+                        if (!(strstr (value, "posix") || strstr (value, "acl")
+                              || strstr (value, "locks") ||
+                              strstr (value, "io-threads") ||
+                              strstr (value, "marker") ||
+                              strstr (value, "index"))) {
+                                words++;
+                                continue;
+                        } else {
+                                debug_xlator = gf_strdup (key);
+                                break;
+                        }
+                }
+        }
+
+        return debug_xlator;
+}
+
 int
 gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
                              int count, void *myframe)
@@ -1441,6 +1622,8 @@ gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
         dict_t               *dict = NULL;
         char                 *help_str = NULL;
         char                 msg[1024] = {0,};
+        char                 *debug_xlator = _gf_false;
+        char                 tmp_str[512] = {0,};
 
         if (-1 == req->rpc_status) {
                 goto out;
@@ -1448,7 +1631,8 @@ gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -1463,9 +1647,21 @@ gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len, &dict);
 
+        /* For brick processes graph change does not happen on the fly.
+         * The proces has to be restarted. So this is a check from the
+         * volume set option such that if debug xlators such as trace/errorgen
+         * are provided in the set command, warn the user.
+         */
+        debug_xlator = is_server_debug_xlator (myframe);
+
         if (dict_get_str (dict, "help-str", &help_str) && !msg[0])
                 snprintf (msg, sizeof (msg), "Set volume %s",
                           (rsp.op_ret) ? "unsuccessful": "successful");
+        if (rsp.op_ret == 0 && debug_xlator) {
+                snprintf (tmp_str, sizeof (tmp_str), "\n%s translator has been "
+                          "added to the server volume file. Please restart the"
+                          " volume for enabling the translator", debug_xlator);
+        }
 
         if ((global_state->mode & GLUSTER_MODE_XML) && (help_str == NULL)) {
                 ret = cli_xml_output_str ("volSet", msg, rsp.op_ret,
@@ -1476,16 +1672,20 @@ gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
-        if (rsp.op_ret &&  strcmp (rsp.op_errstr, ""))
-                cli_err ("volume set: failed: %s", rsp.op_errstr);
-
-        if (!rsp.op_ret) {
-                if (help_str == NULL)
-                        cli_out ("volume set: success");
+        if (rsp.op_ret) {
+                if (strcmp (rsp.op_errstr, ""))
+                        cli_err ("volume set: failed: %s", rsp.op_errstr);
                 else
-                        cli_out ("%s", help_str);
+                        cli_err ("volume set: failed");
         } else {
-                cli_err ("volume set: failed");
+                if (help_str == NULL) {
+                        if (debug_xlator == NULL)
+                                cli_out ("volume set: success");
+                        else
+                                cli_out ("volume set: success%s", tmp_str);
+                }else {
+                        cli_out ("%s", help_str);
+                }
         }
 
         ret = rsp.op_ret;
@@ -1493,6 +1693,7 @@ gf_cli_set_volume_cbk (struct rpc_req *req, struct iovec *iov,
 out:
         if (dict)
                 dict_unref (dict);
+        GF_FREE (debug_xlator);
         cli_cmd_broadcast_response (ret);
         return ret;
 }
@@ -1511,7 +1712,8 @@ gf_cli_add_brick_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -1561,31 +1763,58 @@ gf_cli3_remove_brick_status_cbk (struct rpc_req *req, struct iovec *iov,
         char                     key[256] = {0,};
         int32_t                  i       = 1;
         int32_t                  counter = 0;
-        char                    *node_uuid = 0;
+        char                    *node_name = 0;
         gf_defrag_status_t       status_rcd = GF_DEFRAG_STATUS_NOT_STARTED;
         uint64_t                 failures = 0;
+        uint64_t                 skipped = 0;
         double                   elapsed = 0;
         char                    *size_str = NULL;
+        int32_t                  command = 0;
+        gf1_op_commands          cmd = GF_OP_CMD_NONE;
+        cli_local_t             *local = NULL;
+        call_frame_t            *frame = NULL;
+        char                    *cmd_str = "unknown";
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp,
                               (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        if (frame)
+                local = frame->local;
+        ret = dict_get_int32 (local->dict, "command", &command);
+        if (ret)
                 goto out;
+        cmd = command;
+
+        switch (cmd) {
+        case GF_OP_CMD_STOP:
+                cmd_str = "stop";
+                break;
+        case GF_OP_CMD_STATUS:
+                cmd_str = "status";
+                break;
+        default:
+                break;
         }
 
         ret = rsp.op_ret;
         if (rsp.op_ret == -1) {
                 if (strcmp (rsp.op_errstr, ""))
-                        snprintf (msg, sizeof (msg), "volume remove-brick: "
-                                  "failed: %s", rsp.op_errstr);
+                        snprintf (msg, sizeof (msg), "volume remove-brick %s: "
+                                  "failed: %s", cmd_str, rsp.op_errstr);
                 else
-                        snprintf (msg, sizeof (msg), "volume remove-brick: "
-                                  "failed: status getting failed");
+                        snprintf (msg, sizeof (msg), "volume remove-brick %s: "
+                                  "failed", cmd_str);
 
                 if (global_state->mode & GLUSTER_MODE_XML)
                         goto xml_output;
@@ -1633,63 +1862,69 @@ xml_output:
 
         ret = dict_get_int32 (dict, "count", &counter);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "count not set");
+                gf_log (frame->this->name, GF_LOG_ERROR, "count not set");
                 goto out;
         }
 
 
-        cli_out ("%40s %16s %13s %13s %13s %14s %s", "Node", "Rebalanced-files",
-                 "size", "scanned", "failures", "status", "run-time in secs");
-        cli_out ("%40s %16s %13s %13s %13s %14s %16s", "---------",
+        cli_out ("%40s %16s %13s %13s %13s %13s %14s %s", "Node",
+                 "Rebalanced-files", "size", "scanned", "failures", "skipped",
+                 "status", "run-time in secs");
+        cli_out ("%40s %16s %13s %13s %13s %13s %14s %16s", "---------",
                  "-----------", "-----------", "-----------", "-----------",
-                 "------------", "--------------");
+                  "-----------","------------", "--------------");
 
         do {
-                snprintf (key, 256, "node-uuid-%d", i);
-                ret = dict_get_str (dict, key, &node_uuid);
+                snprintf (key, 256, "node-name-%d", i);
+                ret = dict_get_str (dict, key, &node_name);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
-                                "failed to get node-uuid");
+                        gf_log (frame->this->name, GF_LOG_TRACE,
+                                "failed to get node-name");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "files-%d", i);
                 ret = dict_get_uint64 (dict, key, &files);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get file count");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "size-%d", i);
                 ret = dict_get_uint64 (dict, key, &size);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get size of xfer");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "lookups-%d", i);
                 ret = dict_get_uint64 (dict, key, &lookup);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get lookedup file count");
 
                 memset (key, 0, 256);
                 snprintf (key, 256, "status-%d", i);
                 ret = dict_get_int32 (dict, key, (int32_t *)&status_rcd);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "failed to get status");
 
                 snprintf (key, 256, "failures-%d", i);
                 ret = dict_get_uint64 (dict, key, &failures);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "Failed to get failure on files");
 
+                snprintf (key, 256, "failures-%d", i);
+                ret = dict_get_uint64 (dict, key, &skipped);
+                if (ret)
+                        gf_log (frame->this->name, GF_LOG_TRACE,
+                                "Failed to get skipped files");
                 memset (key, 0, 256);
                 snprintf (key, 256, "run-time-%d", i);
                 ret = dict_get_double (dict, key, &elapsed);
                 if (ret)
-                        gf_log (THIS->name, GF_LOG_TRACE,
+                        gf_log (frame->this->name, GF_LOG_TRACE,
                                 "Failed to get run-time");
 
                 switch (status_rcd) {
@@ -1708,17 +1943,32 @@ xml_output:
                 case GF_DEFRAG_STATUS_FAILED:
                         status = "failed";
                         break;
+                default:
+                        break;
                 }
 
                 size_str = gf_uint64_2human_readable(size);
-                cli_out ("%40s %16"PRIu64 " %13s" " %13"PRIu64 " %13"PRIu64
-                         " %14s %16.2f", node_uuid, files, size_str, lookup,
-                         failures, status, elapsed);
+                
+		if (strcmp (status, "not started")) {
+			cli_out ("%40s %16"PRIu64 " %13s" " %13"PRIu64 " %13"
+				PRIu64 " %13"PRIu64 " %14s %16.2f", node_name,
+                                files, size_str, lookup, failures, skipped,
+                                status, elapsed);
+		}
                 GF_FREE(size_str);
 
                 i++;
         } while (i <= counter);
 
+        if ((cmd == GF_OP_CMD_STOP) && (rsp.op_ret == 0)) {
+                cli_out ("'remove-brick' process may be in the middle of a "
+                         "file migration.\nThe process will be fully stopped "
+                         "once the migration of the file is complete.\nPlease "
+                         "check remove-brick process for completion before "
+                         "doing any further brick related tasks on the "
+                         "volume.");
+        }
+
 out:
         free (rsp.dict.dict_val); //malloced by xdr
         if (dict)
@@ -1739,6 +1989,8 @@ gf_cli_remove_brick_cbk (struct rpc_req *req, struct iovec *iov,
         char                           *cmd_str = "unknown";
         cli_local_t                    *local = NULL;
         call_frame_t                   *frame = NULL;
+        char                           *task_id_str = NULL;
+        dict_t                         *rsp_dict = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
@@ -1749,7 +2001,8 @@ gf_cli_remove_brick_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -1759,10 +2012,31 @@ gf_cli_remove_brick_cbk (struct rpc_req *req, struct iovec *iov,
                  goto out;
         }
 
-        switch (cmd) {
+        if (rsp.dict.dict_len) {
+                rsp_dict = dict_new ();
+                if (!rsp_dict) {
+                        ret = -1;
+                        goto out;
+                }
+
+                ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len,
+                                        &rsp_dict);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Failed to unserialize rsp_dict");
+                        goto out;
+                }
+        }
 
+        switch (cmd) {
         case GF_OP_CMD_START:
                 cmd_str = "start";
+
+                ret = dict_get_str (rsp_dict, GF_REMOVE_BRICK_TID_KEY, &task_id_str);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "remove-brick-id is not present in dict");
+                }
                 break;
         case GF_OP_CMD_COMMIT:
                 cmd_str = "commit";
@@ -1784,19 +2058,23 @@ gf_cli_remove_brick_cbk (struct rpc_req *req, struct iovec *iov,
                           (rsp.op_ret) ? "unsuccessful": "successful");
 
         if (global_state->mode & GLUSTER_MODE_XML) {
-                ret = cli_xml_output_vol_remove_brick (_gf_false, NULL,
+                ret = cli_xml_output_vol_remove_brick (_gf_false, rsp_dict,
                                                        rsp.op_ret, rsp.op_errno,
-                                                       rsp.op_errstr);
+                                                       msg);
                 if (ret)
                         gf_log ("cli", GF_LOG_ERROR,
                                 "Error outputting to xml");
                 goto out;
         }
 
-        if (rsp.op_ret)
-                cli_err ("volume remove-brick: failed: %s", rsp.op_errstr);
-        else
-                cli_out ("volume remove-brick: success");
+        if (rsp.op_ret) {
+                cli_err ("volume remove-brick %s: failed: %s", cmd_str,
+                         msg);
+        } else {
+                cli_out ("volume remove-brick %s: success", cmd_str);
+                if (GF_OP_CMD_START == cmd && task_id_str != NULL)
+                        cli_out ("ID: %s", task_id_str);
+        }
 
         ret = rsp.op_ret;
 
@@ -1825,7 +2103,8 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
         gf1_cli_replace_op               replace_op       = 0;
         char                            *rb_operation_str = NULL;
         dict_t                          *rsp_dict         = NULL;
-        char                             msg[1024]         = {0,};
+        char                             msg[1024]        = {0,};
+        char                            *task_id_str      = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
@@ -1835,7 +2114,8 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -1850,58 +2130,77 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
+        if (rsp.dict.dict_len) {
+                /* Unserialize the dictionary */
+                rsp_dict  = dict_new ();
+
+                ret = dict_unserialize (rsp.dict.dict_val,
+                                rsp.dict.dict_len,
+                                &rsp_dict);
+                if (ret < 0) {
+                        gf_log ("glusterd", GF_LOG_ERROR,
+                                        "failed to "
+                                        "unserialize rsp buffer to dictionary");
+                        goto out;
+                }
+        }
+
         switch (replace_op) {
         case GF_REPLACE_OP_START:
-                if (rsp.op_ret)
-                        rb_operation_str = "replace-brick failed to start";
-                else
-                        rb_operation_str = "replace-brick started successfully";
+                if (rsp.op_ret) {
+                        rb_operation_str = gf_strdup ("replace-brick failed to"
+                                                      " start");
+                } else {
+                        ret = dict_get_str (rsp_dict, GF_REPLACE_BRICK_TID_KEY,
+                                            &task_id_str);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Failed to get "
+                                        "\"replace-brick-id\" from dict");
+                                goto out;
+                        }
+                        ret = gf_asprintf (&rb_operation_str,
+                                           "replace-brick started successfully"
+                                           "\nID: %s", task_id_str);
+                        if (ret < 0)
+                                goto out;
+                }
                 break;
 
         case GF_REPLACE_OP_STATUS:
 
-                if (rsp.op_ret || ret)
-                        rb_operation_str = "replace-brick status unknown";
-                else {
-                        if (rsp.dict.dict_len) {
-                                /* Unserialize the dictionary */
-                                rsp_dict  = dict_new ();
-
-                                ret = dict_unserialize (rsp.dict.dict_val,
-                                                        rsp.dict.dict_len,
-                                                        &rsp_dict);
-                                if (ret < 0) {
-                                        gf_log ("glusterd", GF_LOG_ERROR,
-                                                "failed to "
-                                                "unserialize req-buffer to dictionary");
-                                        goto out;
-                                }
-                        }
+                if (rsp.op_ret || ret) {
+                        rb_operation_str = gf_strdup ("replace-brick status "
+                                                      "unknown");
+                } else {
                         ret = dict_get_str (rsp_dict, "status-reply",
                                             &status_reply);
                         if (ret) {
-                                gf_log (THIS->name, GF_LOG_ERROR, "failed to"
+                                gf_log (frame->this->name, GF_LOG_ERROR, "failed to"
                                         "get status");
                                 goto out;
                         }
 
-                        rb_operation_str = status_reply;
+                        rb_operation_str = gf_strdup (status_reply);
                 }
 
                 break;
 
         case GF_REPLACE_OP_PAUSE:
                 if (rsp.op_ret)
-                        rb_operation_str = "replace-brick pause failed";
+                        rb_operation_str = gf_strdup ("replace-brick pause "
+                                                      "failed");
                 else
-                        rb_operation_str = "replace-brick paused successfully";
+                        rb_operation_str = gf_strdup ("replace-brick paused "
+                                                      "successfully");
                 break;
 
         case GF_REPLACE_OP_ABORT:
                 if (rsp.op_ret)
-                        rb_operation_str = "replace-brick abort failed";
+                        rb_operation_str = gf_strdup ("replace-brick abort "
+                                                      "failed");
                 else
-                        rb_operation_str = "replace-brick aborted successfully";
+                        rb_operation_str = gf_strdup ("replace-brick aborted "
+                                                      "successfully");
                 break;
 
         case GF_REPLACE_OP_COMMIT:
@@ -1922,9 +2221,11 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
 
 
                 if (rsp.op_ret || ret)
-                        rb_operation_str = "replace-brick commit failed";
+                        rb_operation_str = gf_strdup ("replace-brick commit "
+                                                      "failed");
                 else
-                        rb_operation_str = "replace-brick commit successful";
+                        rb_operation_str = gf_strdup ("replace-brick commit "
+                                                      "successful");
 
                 break;
 
@@ -1935,7 +2236,7 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
         }
 
         if (rsp.op_ret && (strcmp (rsp.op_errstr, ""))) {
-                rb_operation_str = rsp.op_errstr;
+                rb_operation_str = gf_strdup (rsp.op_errstr);
         }
 
         gf_log ("cli", GF_LOG_INFO, "Received resp to replace brick");
@@ -1959,6 +2260,17 @@ gf_cli_replace_brick_cbk (struct rpc_req *req, struct iovec *iov,
         ret = rsp.op_ret;
 
 out:
+        if (frame)
+                frame->local = NULL;
+
+        if (local) {
+                dict_unref (local->dict);
+                cli_local_wipe (local);
+        }
+
+        if (rb_operation_str)
+                GF_FREE (rb_operation_str);
+
         cli_cmd_broadcast_response (ret);
         free (rsp.dict.dict_val);
         if (rsp_dict)
@@ -1982,7 +2294,8 @@ gf_cli_log_rotate_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -2030,7 +2343,8 @@ gf_cli_sync_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -2186,15 +2500,19 @@ gf_cli_quota_cbk (struct rpc_req *req, struct iovec *iov,
         char              *volname    = NULL;
         char              *limit_list = NULL;
         int32_t            type       = 0;
-        char               msg[1024] = {0,};
+        char               msg[1024]  = {0,};
+        call_frame_t      *frame      = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -2225,17 +2543,17 @@ gf_cli_quota_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_str (dict, "volname", &volname);
         if (ret)
-                gf_log (THIS->name, GF_LOG_TRACE,
+                gf_log (frame->this->name, GF_LOG_TRACE,
                         "failed to get volname");
 
         ret = dict_get_str (dict, "limit_list", &limit_list);
         if (ret)
-                gf_log (THIS->name, GF_LOG_TRACE,
+                gf_log (frame->this->name, GF_LOG_TRACE,
                         "failed to get limit_list");
 
         ret = dict_get_int32 (dict, "type", &type);
         if (ret)
-                gf_log (THIS->name, GF_LOG_TRACE,
+                gf_log (frame->this->name, GF_LOG_TRACE,
                         "failed to get type");
 
         if (type == GF_QUOTA_OPTION_TYPE_LIST) {
@@ -2304,14 +2622,24 @@ gf_cli_getspec_cbk (struct rpc_req *req, struct iovec *iov,
         gf_getspec_rsp          rsp   = {0,};
         int                     ret   = -1;
         char                   *spec  = NULL;
+        call_frame_t           *frame = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_getspec_rsp);
-        if (ret < 0 || rsp.op_ret == -1) {
-                gf_log ("", GF_LOG_ERROR, "error");
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        if (rsp.op_ret == -1) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "getspec failed");
                 goto out;
         }
 
@@ -2341,14 +2669,24 @@ gf_cli_pmap_b2p_cbk (struct rpc_req *req, struct iovec *iov,
         pmap_port_by_brick_rsp rsp = {0,};
         int                     ret   = -1;
         char                   *spec  = NULL;
+        call_frame_t           *frame = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_pmap_port_by_brick_rsp);
-        if (ret < 0 || rsp.op_ret == -1) {
-                gf_log ("", GF_LOG_ERROR, "error");
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        if (rsp.op_ret == -1) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "pump_b2p failed");
                 goto out;
         }
 
@@ -2369,10 +2707,9 @@ int32_t
 gf_cli_probe (call_frame_t *frame, xlator_t *this,
                  void *data)
 {
-        gf1_cli_probe_req  req      = {0,};
+        gf_cli_req         req      = {{0,},};
         int                ret      = 0;
         dict_t            *dict     = NULL;
-        char              *hostname = NULL;
         int                port     = 0;
 
         if (!frame || !this ||  !data) {
@@ -2381,24 +2718,22 @@ gf_cli_probe (call_frame_t *frame, xlator_t *this,
         }
 
         dict = data;
-        ret = dict_get_str (dict, "hostname", &hostname);
-        if (ret)
-                goto out;
 
         ret = dict_get_int32 (dict, "port", &port);
-        if (ret)
-                port = CLI_GLUSTERD_PORT;
-
-        req.hostname = hostname;
-        req.port     = port;
+        if (ret) {
+                ret = dict_set_int32 (dict, "port", CLI_GLUSTERD_PORT);
+                if (ret)
+                        goto out;
+        }
 
-        ret = cli_cmd_submit (&req, frame, cli_rpc_prog,
-                              GLUSTER_CLI_PROBE, NULL,
-                              this, gf_cli_probe_cbk,
-                              (xdrproc_t)xdr_gf1_cli_probe_req);
+        ret = cli_to_glusterd (&req, frame, gf_cli_probe_cbk,
+                               (xdrproc_t) xdr_gf_cli_req, dict,
+                               GLUSTER_CLI_PROBE, this, cli_rpc_prog, NULL);
 
 out:
+        GF_FREE (req.dict.dict_val);
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+
         return ret;
 }
 
@@ -2406,10 +2741,9 @@ int32_t
 gf_cli_deprobe (call_frame_t *frame, xlator_t *this,
                    void *data)
 {
-        gf1_cli_deprobe_req  req      = {0,};
+        gf_cli_req           req      = {{0,},};
         int                  ret      = 0;
         dict_t              *dict     = NULL;
-        char                *hostname = NULL;
         int                  port     = 0;
         int                  flags    = 0;
 
@@ -2419,51 +2753,64 @@ gf_cli_deprobe (call_frame_t *frame, xlator_t *this,
         }
 
         dict = data;
-        ret = dict_get_str (dict, "hostname", &hostname);
-        if (ret)
-                goto out;
-
         ret = dict_get_int32 (dict, "port", &port);
-        if (ret)
-                port = CLI_GLUSTERD_PORT;
+        if (ret) {
+                ret = dict_set_int32 (dict, "port", CLI_GLUSTERD_PORT);
+                if (ret)
+                        goto out;
+        }
 
         ret = dict_get_int32 (dict, "flags", &flags);
-        if (ret)
-                flags = 0;
+        if (ret) {
+                ret = dict_set_int32 (dict, "flags", 0);
+                if (ret)
+                        goto out;
+        }
 
-        req.hostname = hostname;
-        req.port     = port;
-        req.flags    = flags;
-        ret = cli_cmd_submit (&req, frame, cli_rpc_prog,
-                              GLUSTER_CLI_DEPROBE, NULL,
-                              this, gf_cli_deprobe_cbk,
-                              (xdrproc_t)xdr_gf1_cli_deprobe_req);
+        ret = cli_to_glusterd (&req, frame, gf_cli_deprobe_cbk,
+                               (xdrproc_t)xdr_gf_cli_req, dict,
+                              GLUSTER_CLI_DEPROBE, this, cli_rpc_prog, NULL);
 
 out:
+        GF_FREE (req.dict.dict_val);
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+
         return ret;
 }
 
 int32_t
 gf_cli_list_friends (call_frame_t *frame, xlator_t *this,
-                        void *data)
+                     void *data)
 {
         gf1_cli_peer_list_req   req = {0,};
         int                     ret = 0;
+        unsigned long           flags = 0;
 
         if (!frame || !this) {
                 ret = -1;
                 goto out;
         }
 
-        req.flags = GF_CLI_LIST_ALL;
+        GF_ASSERT (frame->local == NULL);
 
+        flags = (long)data;
+        req.flags = flags;
+        frame->local = (void*)flags;
         ret = cli_cmd_submit (&req, frame, cli_rpc_prog,
                               GLUSTER_CLI_LIST_FRIENDS, NULL,
                               this, gf_cli_list_friends_cbk,
                               (xdrproc_t) xdr_gf1_cli_peer_list_req);
 
 out:
+        if (ret) {
+                /*
+                 * If everything goes fine, gf_cli_list_friends_cbk()
+                 * [invoked through cli_cmd_submit()]resets the
+                 * frame->local to NULL. In case cli_cmd_submit()
+                 * fails in between, RESET frame->local here.
+                 */
+                frame->local = NULL;
+        }
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
 }
@@ -2556,7 +2903,7 @@ gf_cli_get_volume (call_frame_t *frame, xlator_t *this,
         flags = ctx->flags;
         ret = dict_set_int32 (dict, "flags", flags);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "failed to set flags");
+                gf_log (frame->this->name, GF_LOG_ERROR, "failed to set flags");
                 goto out;
         }
 
@@ -2579,7 +2926,7 @@ out:
 }
 
 int32_t
-gf_cli3_1_uuid_reset (call_frame_t *frame, xlator_t *this,
+gf_cli3_1_uuid_get (call_frame_t *frame, xlator_t *this,
                       void *data)
 {
         gf_cli_req                      req = {{0,}};
@@ -2592,148 +2939,37 @@ gf_cli3_1_uuid_reset (call_frame_t *frame, xlator_t *this,
         }
 
         dict = data;
-        ret = cli_to_glusterd (&req, frame, gf_cli3_1_uuid_reset_cbk,
+        ret = cli_to_glusterd (&req, frame, gf_cli3_1_uuid_get_cbk,
                                (xdrproc_t)xdr_gf_cli_req, dict,
-                               GLUSTER_CLI_UUID_RESET, this, cli_rpc_prog,
+                               GLUSTER_CLI_UUID_GET, this, cli_rpc_prog,
                                NULL);
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
 }
 
-#ifdef HAVE_BD_XLATOR
-int
-gf_cli_bd_op_cbk (struct rpc_req *req, struct iovec *iov,
-                             int count, void *myframe)
-{
-        gf_cli_rsp              rsp         = {0,};
-        int                     ret         = -1;
-        cli_local_t             *local      = NULL;
-        dict_t                  *dict       = NULL;
-        dict_t                  *input_dict = NULL;
-        gf_xl_bd_op_t           bd_op       = GF_BD_OP_INVALID;
-        char                    *operation  = NULL;
-        call_frame_t            *frame      = NULL;
-
-        if (-1 == req->rpc_status)
-                goto out;
-
-        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
-        if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
-                goto out;
-        }
-
-        dict = dict_new ();
-        if (!dict) {
-                ret = -1;
-                goto out;
-        }
-
-        frame = myframe;
-        if (frame)
-                local = frame->local;
-
-        if (local) {
-                input_dict = local->dict;
-                ret = dict_get_int32 (input_dict, "bd-op",
-                                      (int32_t *)&bd_op);
-        }
-
-        switch (bd_op) {
-        case GF_BD_OP_NEW_BD:
-                operation = gf_strdup ("create");
-                break;
-        case GF_BD_OP_DELETE_BD:
-                operation = gf_strdup ("delete");
-                break;
-        case GF_BD_OP_CLONE_BD:
-                operation = gf_strdup ("clone");
-                break;
-        case GF_BD_OP_SNAPSHOT_BD:
-                operation = gf_strdup ("snapshot");
-                break;
-        default:
-                break;
-        }
-
-        ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len, &dict);
-        if (ret)
-                goto out;
-
-        gf_log ("cli", GF_LOG_INFO, "Received resp to %s bd op", operation);
-
-        if (global_state->mode & GLUSTER_MODE_XML) {
-                ret = cli_xml_output_dict ("BdOp", dict, rsp.op_ret,
-                                           rsp.op_errno, rsp.op_errstr);
-                if (ret)
-                        gf_log ("cli", GF_LOG_ERROR,
-                                "Error outputting to xml");
-                goto out;
-        }
-
-        if (rsp.op_ret && strcmp (rsp.op_errstr, ""))
-                cli_err ("%s", rsp.op_errstr);
-        else
-                cli_out ("BD %s has been %s", operation,
-                                (rsp.op_ret) ? "unsuccessful":
-                                "successful.");
-        ret = rsp.op_ret;
-
-out:
-        cli_cmd_broadcast_response (ret);
-
-        if (dict)
-                dict_unref (dict);
-
-        if (operation)
-                GF_FREE (operation);
-
-        if (rsp.dict.dict_val)
-                free (rsp.dict.dict_val);
-        if (rsp.op_errstr)
-                free (rsp.op_errstr);
-        return ret;
-}
-
 int32_t
-gf_cli_bd_op (call_frame_t *frame, xlator_t *this,
+gf_cli3_1_uuid_reset (call_frame_t *frame, xlator_t *this,
                       void *data)
 {
-        gf_cli_req      req    = { {0,} };
-        int             ret    = 0;
-        dict_t          *dict  = NULL;
+        gf_cli_req                      req = {{0,}};
+        int                             ret = 0;
+        dict_t                          *dict = NULL;
 
         if (!frame || !this || !data) {
                 ret = -1;
                 goto out;
         }
 
-        dict = dict_ref ((dict_t *)data);
-        if (!dict)
-                goto out;
-
-        ret = dict_allocate_and_serialize (dict,
-                                           &req.dict.dict_val,
-                                           &req.dict.dict_len);
-
-
-        ret = cli_cmd_submit (&req, frame, cli_rpc_prog,
-                              GLUSTER_CLI_BD_OP, NULL,
-                              this, gf_cli_bd_op_cbk,
-                              (xdrproc_t) xdr_gf_cli_req);
-
+        dict = data;
+        ret = cli_to_glusterd (&req, frame, gf_cli3_1_uuid_reset_cbk,
+                               (xdrproc_t)xdr_gf_cli_req, dict,
+                               GLUSTER_CLI_UUID_RESET, this, cli_rpc_prog,
+                               NULL);
 out:
-        if (dict)
-                dict_unref (dict);
-
-        if (req.dict.dict_val)
-                GF_FREE (req.dict.dict_val);
-
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
 }
-#endif
 
 int32_t
 gf_cli_create_volume (call_frame_t *frame, xlator_t *this,
@@ -3030,7 +3266,7 @@ gf_cli_remove_brick (call_frame_t *frame, xlator_t *this,
                                        GLUSTER_CLI_REMOVE_BRICK, this,
                                        cli_rpc_prog, NULL);
         } else {
-                /* Need rebalance status to e sent :-) */
+                /* Need rebalance status to be sent :-) */
                 req_dict = dict_new ();
                 if (!req_dict) {
                         ret = -1;
@@ -3039,7 +3275,7 @@ gf_cli_remove_brick (call_frame_t *frame, xlator_t *this,
 
                 ret = dict_set_str (req_dict, "volname", volname);
                 if (ret) {
-                        gf_log (THIS->name, GF_LOG_ERROR,
+                        gf_log (this->name, GF_LOG_ERROR,
                                 "Failed to set dict");
                         goto out;
                 }
@@ -3051,7 +3287,7 @@ gf_cli_remove_brick (call_frame_t *frame, xlator_t *this,
 
                 ret = dict_set_int32 (req_dict, "rebalance-command", (int32_t) cmd);
                 if (ret) {
-                        gf_log (THIS->name, GF_LOG_ERROR,
+                        gf_log (this->name, GF_LOG_ERROR,
                                 "Failed to set dict");
                         goto out;
                 }
@@ -3202,6 +3438,7 @@ gf_cli_getspec (call_frame_t *frame, xlator_t *this,
         gf_getspec_req          req = {0,};
         int                     ret = 0;
         dict_t                  *dict = NULL;
+        dict_t                  *op_dict = NULL;
 
         if (!frame || !this ||  !data) {
                 ret = -1;
@@ -3214,12 +3451,45 @@ gf_cli_getspec (call_frame_t *frame, xlator_t *this,
         if (ret)
                 goto out;
 
+        op_dict = dict_new ();
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        // Set the supported min and max op-versions, so glusterd can make a
+        // decision
+        ret = dict_set_int32 (op_dict, "min-op-version", GD_OP_VERSION_MIN);
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_ERROR, "Failed to set min-op-version"
+                        " in request dict");
+                goto out;
+        }
+
+        ret = dict_set_int32 (op_dict, "max-op-version", GD_OP_VERSION_MAX);
+        if (ret) {
+                gf_log (THIS->name, GF_LOG_ERROR, "Failed to set max-op-version"
+                        " in request dict");
+                goto out;
+        }
+
+        ret = dict_allocate_and_serialize (op_dict, &req.xdata.xdata_val,
+                                           &req.xdata.xdata_len);
+        if (ret < 0) {
+                gf_log (THIS->name, GF_LOG_ERROR,
+                        "Failed to serialize dictionary");
+                goto out;
+        }
+
         ret = cli_cmd_submit (&req, frame, &cli_handshake_prog,
                               GF_HNDSK_GETSPEC, NULL,
                               this, gf_cli_getspec_cbk,
                               (xdrproc_t) xdr_gf_getspec_req);
 
 out:
+        if (op_dict) {
+                dict_unref(op_dict);
+        }
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
 
         return ret;
@@ -3300,7 +3570,8 @@ gf_cli_fsm_log_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_fsm_log_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -3400,8 +3671,11 @@ gf_cli_gsync_config_command (dict_t *dict)
         char *subop         = NULL;
         char *gwd           = NULL;
         char *slave         = NULL;
+        char *confpath      = NULL;
         char *master        = NULL;
         char *op_name       = NULL;
+        int   ret           = -1;
+        char  conf_path[PATH_MAX] = "";
 
         if (dict_get_str (dict, "subop", &subop) != 0)
                 return -1;
@@ -3420,9 +3694,17 @@ gf_cli_gsync_config_command (dict_t *dict)
         if (dict_get_str (dict, "op_name", &op_name) != 0)
                 op_name = NULL;
 
+        ret = dict_get_str (dict, "conf_path", &confpath);
+        if (!confpath) {
+                ret = snprintf (conf_path, sizeof(conf_path) - 1,
+                                "%s/"GEOREP"/gsyncd_template.conf", gwd);
+                conf_path[ret] = '\0';
+                confpath = conf_path;
+        }
+
         runinit (&runner);
         runner_add_args (&runner, GSYNCD_PREFIX"/gsyncd", "-c", NULL);
-        runner_argprintf (&runner, "%s/"GSYNC_CONF, gwd);
+        runner_argprintf (&runner, "%s", confpath);
         if (master)
                 runner_argprintf (&runner, ":%s", master);
         runner_add_arg (&runner, slave);
@@ -3434,67 +3716,639 @@ gf_cli_gsync_config_command (dict_t *dict)
 }
 
 int
-gf_cli_gsync_out_status (dict_t *dict)
+gf_cli_fetch_gsyncd_status_values (char *status,
+                                   gf_cli_gsync_status_t *sts_val)
 {
-        int   gsync_count              = 0;
-        int   i                        = 0;
-        int   ret                      = 0;
-        char             mst[PATH_MAX] = {0, };
-        char             slv[PATH_MAX] = {0, };
-        char             sts[PATH_MAX] = {0, };
-        char             nds[PATH_MAX] = {0, };
-        char             hyphens[100]  = {0, };
-        char *mst_val                  = NULL;
-        char *slv_val                  = NULL;
-        char *sts_val                  = NULL;
-        char *nds_val                  = NULL;
-
-        cli_out ("%-20s %-20s %-50s %-10s", "NODE", "MASTER", "SLAVE", "STATUS");
-
-        for (i=0; i<sizeof(hyphens)-1; i++)
-                hyphens[i] = '-';
+        int32_t   ret      = -1;
+        char     *tmp      = NULL;
+        char     *save_ptr = NULL;
+        char     *key      = NULL;
+        char     *value    = NULL;
 
-        cli_out ("%s", hyphens);
+        if (!status || !sts_val) {
+                gf_log ("", GF_LOG_ERROR, "status or sts_val is null");
+                goto out;
+        }
 
+        tmp = strtok_r (status, "\n", &save_ptr);
 
-        ret = dict_get_int32 (dict, "gsync-count", &gsync_count);
+        if (tmp)
+                sts_val->health = gf_strdup (tmp);
+
+        while (tmp) {
+                key = strtok_r (tmp, "=", &value);
+
+                if ((key) && (!strcmp(key, "Uptime")))
+                        sts_val->uptime = gf_strdup (value);
+
+                if ((key) && (!strcmp(key, "FilesSyncd")))
+                        sts_val->files_syncd = gf_strdup (value);
+
+                if ((key) && (!strcmp(key, "FilesPending")))
+                        sts_val->files_pending = gf_strdup (value);
+
+                if ((key) && (!strcmp(key, "BytesPending"))) {
+                        value = gf_uint64_2human_readable(atol(value));
+                        sts_val->bytes_pending = gf_strdup (value);
+                }
+
+                if ((key) && (!strcmp(key, "DeletesPending")))
+                        sts_val->deletes_pending = gf_strdup (value);
+
+                tmp = strtok_r (NULL, ";", &save_ptr);
+        }
+
+        if (sts_val->health)
+                ret = 0;
+
+        if (!sts_val->uptime)
+                sts_val->uptime = gf_strdup ("N/A");
+
+        if (!sts_val->files_syncd)
+                sts_val->files_syncd = gf_strdup ("N/A");
+
+        if (!sts_val->files_pending)
+                sts_val->files_pending = gf_strdup ("N/A");
+
+        if (!sts_val->bytes_pending)
+                sts_val->bytes_pending = gf_strdup ("N/A");
+
+        if (!sts_val->deletes_pending)
+                sts_val->deletes_pending = gf_strdup ("N/A");
+
+out:
+        gf_log ("", GF_LOG_DEBUG, "Returning %d.", ret);
+        return ret;
+}
+
+char*
+get_struct_variable (int mem_num, gf_cli_gsync_status_t *sts_val)
+{
+        switch (mem_num) {
+        case 0: return (sts_val->node);
+        case 1: return (sts_val->master);
+        case 2: return (sts_val->slave);
+        case 3: return (sts_val->health);
+        case 4: return (sts_val->uptime);
+        case 5: return (sts_val->files_syncd);
+        case 6: return (sts_val->files_pending);
+        case 7: return (sts_val->bytes_pending);
+        case 8: return (sts_val->deletes_pending);
+        default:
+                 goto out;
+        }
+
+out:
+        return NULL;
+}
+
+int
+gf_cli_print_status (char **title_values,
+                     gf_cli_gsync_status_t **sts_vals,
+                     int *spacing, int gsync_count,
+                     int number_of_fields, int is_detail)
+{
+        int     indents                  = 0;
+        int     i                        = 0;
+        int     j                        = 0;
+        int     ret                      = 0;
+        int     total_spacing            = 0;
+        char  **output_values            = NULL;
+        char   *tmp                      = NULL;
+        char   *hyphens                  = NULL;
+        char    heading[PATH_MAX]        = {0, };
+        char    indent_spaces[PATH_MAX]  = {0, };
+
+        /* calculating spacing for hyphens */
+        for (i = 0; i < number_of_fields; i++) {
+                /* Suppressing master and slave output for status detail */
+                if ((is_detail) && ((i == 1) || (i == 2))) {
+                        total_spacing++;
+                        continue;
+                } else if ((!is_detail) && (i > 4)) {
+                       /* Suppressing detailed output for
+                        * status */
+                        continue;
+                }
+                spacing[i] += 3; /* Adding extra space to
+                                    distinguish between fields */
+                total_spacing += spacing[i];
+        }
+        total_spacing += 4; /* For the spacing between the fields */
+
+        /* char pointers for each field */
+        output_values = GF_CALLOC (number_of_fields, sizeof (char *),
+                                   gf_common_mt_char);
+        if (!output_values) {
+                ret = -1;
+                goto out;
+        }
+        for (i = 0; i < number_of_fields; i++) {
+                output_values[i] = GF_CALLOC (spacing[i] + 1, sizeof (char),
+                                              gf_common_mt_char);
+                if (!output_values[i]) {
+                        ret = -1;
+                        goto out;
+                }
+        }
+
+        hyphens = GF_CALLOC (total_spacing + 1, sizeof (char),
+                             gf_common_mt_char);
+        if (!hyphens) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = snprintf(heading, sizeof(heading), "MASTER: %s  SLAVE: %s",
+                       sts_vals[0]->master, sts_vals[0]->slave);
         if (ret) {
-                gf_log ("cli", GF_LOG_INFO, "No active geo-replication sessions"
-                        "present for the selected");
+                if (ret < sizeof(heading))
+                        heading[ret] = '\0';
+                else
+                        heading[sizeof(heading) - 1] = '\0';
                 ret = 0;
+        } else {
+                ret = -1;
                 goto out;
         }
 
-        for (i = 1; i <= gsync_count; i++) {
-                snprintf (nds, sizeof(nds), "node%d", i);
-                snprintf (mst, sizeof(mst), "master%d", i);
-                snprintf (slv, sizeof(slv), "slave%d", i);
-                snprintf (sts, sizeof(sts), "status%d", i);
+        if (is_detail) {
+                cli_out (" ");
+                if (strlen(heading) > total_spacing)
+                        cli_out ("%s", heading);
+                else {
+                        /* Printing the heading with centre justification */
+                        indents = (total_spacing - strlen(heading)) / 2;
+                        memset (indent_spaces, ' ', indents);
+                        indent_spaces[indents] = '\0';
+                        ret = snprintf (hyphens, total_spacing, "%s%s",
+                                        indent_spaces, heading);
+                        if (ret) {
+                                hyphens[ret] = '\0';
+                                cli_out ("%s", hyphens);
+                                ret = 0;
+                        } else {
+                                ret = -1;
+                                goto out;
+                        }
+                }
+                cli_out (" ");
+        }
 
-                ret = dict_get_str (dict, nds, &nds_val);
+        /* setting the title "NODE", "MASTER", etc. from title_values[]
+           and printing the same */
+        for (j = 0; j < number_of_fields; j++) {
+                /* Suppressing master and slave output for status detail */
+                if ((is_detail) && ((j == 1) || (j == 2))) {
+                        output_values[j][0] = '\0';
+                        continue;
+                } else if ((!is_detail) && (j > 4)) {
+                       /* Suppressing detailed output for
+                        * status */
+                       output_values[j][0] = '\0';
+                        continue;
+                }
+                memset (output_values[j], ' ', spacing[j]);
+                memcpy (output_values[j], title_values[j],
+                        strlen(title_values[j]));
+                output_values[j][spacing[j]] = '\0';
+        }
+        cli_out ("%s %s %s %s %s %s %s %s %s", output_values[0],
+                 output_values[1], output_values[2], output_values[3],
+                 output_values[4], output_values[5], output_values[6],
+                 output_values[7], output_values[8]);
+
+        /* setting and printing the hyphens */
+        memset (hyphens, '-', total_spacing);
+        hyphens[total_spacing] = '\0';
+        cli_out ("%s", hyphens);
+
+        for (i = 0; i < gsync_count; i++) {
+                for (j = 0; j < number_of_fields; j++) {
+                        /* Suppressing master and slave output for
+                         * status detail */
+                        if ((is_detail) && ((j == 1) || (j == 2))) {
+                                output_values[j][0] = '\0';
+                                continue;
+                        }  else if ((!is_detail) && (j > 4)) {
+                                /* Suppressing detailed output for
+                                 * status */
+                                output_values[j][0] = '\0';
+                                continue;
+                        }
+                        tmp = get_struct_variable(j, sts_vals[i]);
+                        if (!tmp) {
+                                gf_log ("", GF_LOG_ERROR,
+                                        "struct member empty.");
+                                ret = -1;
+                                goto out;
+                        }
+                        memset (output_values[j], ' ', spacing[j]);
+                        memcpy (output_values[j], tmp, strlen (tmp));
+                        output_values[j][spacing[j]] = '\0';
+                }
+
+                cli_out ("%s %s %s %s %s %s %s %s %s", output_values[0],
+                         output_values[1], output_values[2], output_values[3],
+                         output_values[4], output_values[5], output_values[6],
+                         output_values[7], output_values[8]);
+        }
+
+out:
+        if (output_values) {
+                for (i = 0; i < number_of_fields; i++) {
+                        if (output_values[i])
+                                GF_FREE (output_values[i]);
+                }
+                GF_FREE (output_values);
+        }
+
+        if (hyphens)
+                GF_FREE (hyphens);
+
+        return ret;
+}
+
+int
+gf_cli_read_status_data (dict_t *dict,
+                         gf_cli_gsync_status_t **sts_vals,
+                         int *spacing, int gsync_count,
+                         int number_of_fields)
+{
+        int     ret            = 0;
+        int     i              = 0;
+        int     j              = 0;
+        char    mst[PATH_MAX]  = {0, };
+        char    slv[PATH_MAX]  = {0, };
+        char    sts[PATH_MAX]  = {0, };
+        char    nds[PATH_MAX]  = {0, };
+        char   *status         = NULL;
+        char   *tmp            = NULL;
+
+        /* Storing per node status info in each object */
+        for (i = 0; i < gsync_count; i++) {
+                snprintf (nds, sizeof(nds), "node%d", i + 1);
+                snprintf (mst, sizeof(mst), "master%d", i + 1);
+                snprintf (slv, sizeof(slv), "slave%d", i + 1);
+                snprintf (sts, sizeof(sts), "status%d", i + 1);
+
+                /* Fetching the values from dict, and calculating
+                   the max length for each field */
+                ret = dict_get_str (dict, nds, &(sts_vals[i]->node));
                 if (ret)
                         goto out;
 
-                ret = dict_get_str (dict, mst, &mst_val);
+                ret = dict_get_str (dict, mst, &(sts_vals[i]->master));
                 if (ret)
                         goto out;
 
-                ret = dict_get_str (dict, slv, &slv_val);
+                ret = dict_get_str (dict, slv, &(sts_vals[i]->slave));
                 if (ret)
                         goto out;
 
-                ret = dict_get_str (dict, sts, &sts_val);
+                ret = dict_get_str (dict, sts, &status);
                 if (ret)
                         goto out;
 
-                cli_out ("%-20s %-20s %-50s %-10s", nds_val, mst_val,
-                         slv_val, sts_val);
+                /* Fetching health and uptime from sts_val */
+                ret = gf_cli_fetch_gsyncd_status_values (status, sts_vals[i]);
+                if (ret)
+                        goto out;
 
+                for (j = 0; j < number_of_fields; j++) {
+                        tmp = get_struct_variable(j, sts_vals[i]);
+                        if (!tmp) {
+                                gf_log ("", GF_LOG_ERROR,
+                                        "struct member empty.");
+                                ret = -1;
+                                goto out;
+                        }
+                        if (strlen (tmp) > spacing[j])
+                                spacing[j] = strlen (tmp);
+                }
         }
 
- out:
+out:
+        return ret;
+}
+
+int
+gf_cli_gsync_status_output (dict_t *dict, int status_detail)
+{
+        int                     gsync_count    = 0;
+        int                     i              = 0;
+        int                     j              = 0;
+        int                     ret            = 0;
+        int                     spacing[10]    = {0};
+        int                     num_of_fields  = 9;
+        char                    errmsg[1024]   = "";
+        char                   *master         = NULL;
+        char                   *slave          = NULL;
+        char                   *tmp            = NULL;
+        char                   *title_values[] = {"NODE", "MASTER", "SLAVE",
+                                                  "HEALTH", "UPTIME",
+                                                  "FILES SYNCD",
+                                                  "FILES PENDING",
+                                                  "BYTES PENDING",
+                                                  "DELETES PENDING"};
+        gf_cli_gsync_status_t **sts_vals = NULL;
+
+        /* Checks if any session is active or not */
+        ret = dict_get_int32 (dict, "gsync-count", &gsync_count);
+        if (ret) {
+                ret = dict_get_str (dict, "master", &master);
+
+                ret = dict_get_str (dict, "slave", &slave);
+
+                if (master) {
+                        if (slave)
+                                snprintf (errmsg, sizeof(errmsg), "No active "
+                                          "geo-replication sessions between %s"
+                                          " and %s", master, slave);
+                        else
+                                snprintf (errmsg, sizeof(errmsg), "No active "
+                                          "geo-replication sessions for %s",
+                                          master);
+                } else
+                        snprintf (errmsg, sizeof(errmsg), "No active "
+                                  "geo-replication sessions");
+
+                gf_log ("cli", GF_LOG_INFO, "%s", errmsg);
+                cli_out ("%s", errmsg);
+                ret = 0;
+                goto out;
+        }
+
+        for (i = 0; i < num_of_fields; i++)
+                spacing[i] = strlen(title_values[i]);
+
+        /* gsync_count = number of nodes reporting output.
+           each sts_val object will store output of each
+           node */
+        sts_vals = GF_CALLOC (gsync_count, sizeof (gf_cli_gsync_status_t *),
+                              gf_common_mt_char);
+        if (!sts_vals) {
+                ret = -1;
+                goto out;
+        }
+        for (i = 0; i < gsync_count; i++) {
+                sts_vals[i] = GF_CALLOC (1, sizeof (gf_cli_gsync_status_t),
+                                         gf_common_mt_char);
+                if (!sts_vals[i]) {
+                        ret = -1;
+                        goto out;
+                }
+        }
+
+        ret = gf_cli_read_status_data (dict, sts_vals, spacing,
+                                       gsync_count, num_of_fields);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR, "Unable to read status data");
+                goto out;
+        }
+
+        ret = gf_cli_print_status (title_values, sts_vals, spacing, gsync_count,
+                                   num_of_fields, status_detail);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR, "Unable to print status output");
+                goto out;
+        }
+
+out:
+        if (sts_vals) {
+                for (i = 0; i < gsync_count; i++) {
+                        for (j = 3; j < num_of_fields; j++) {
+                                tmp = get_struct_variable(j, sts_vals[i]);
+                                if (tmp)
+                                        GF_FREE (tmp);
+                        }
+                }
+                GF_FREE (sts_vals);
+        }
+
+        return ret;
+}
+
+static int32_t
+write_contents_to_common_pem_file (dict_t *dict, int output_count)
+{
+        char            *workdir                   = NULL;
+        char             common_pem_file[PATH_MAX] = "";
+        char            *output                    = NULL;
+        char             output_name[PATH_MAX]     = "";
+        int              bytes_writen              = 0;
+        int              fd                        = -1;
+        int              ret                       = -1;
+        int              i                         = -1;
+
+        ret = dict_get_str (dict, "glusterd_workdir", &workdir);
+        if (ret || !workdir) {
+                gf_log ("", GF_LOG_ERROR, "Unable to fetch workdir");
+                ret = -1;
+                goto out;
+        }
+
+        snprintf (common_pem_file, sizeof(common_pem_file),
+                  "%s/geo-replication/common_secret.pem.pub",
+                  workdir);
+
+        unlink (common_pem_file);
+
+        fd = open (common_pem_file, O_WRONLY | O_CREAT, 0600);
+        if (fd == -1) {
+                gf_log ("", GF_LOG_ERROR, "Failed to open %s"
+                        " Error : %s", common_pem_file,
+                        strerror (errno));
+                ret = -1;
+                goto out;
+        }
+
+        for (i = 1; i <= output_count; i++) {
+                memset (output_name, '\0', sizeof (output_name));
+                snprintf (output_name, sizeof (output_name),
+                          "output_%d", i);
+                ret = dict_get_str (dict, output_name, &output);
+                if (ret) {
+                        gf_log ("", GF_LOG_ERROR, "Failed to get %s.",
+                                output_name);
+                        cli_out ("Unable to fetch output.");
+                }
+                if (output) {
+                        bytes_writen = write (fd, output, strlen(output));
+                        if (bytes_writen != strlen(output)) {
+                                gf_log ("", GF_LOG_ERROR, "Failed to write "
+                                        "to %s", common_pem_file);
+                                ret = -1;
+                                goto out;
+                        }
+                        /* Adding the new line character */
+                        bytes_writen = write (fd, "\n", strlen("\n"));
+                        if (bytes_writen != strlen("\n")) {
+                                gf_log ("", GF_LOG_ERROR,
+                                        "Failed to add new line char");
+                                ret = -1;
+                                goto out;
+                        }
+                        output = NULL;
+                }
+        }
+
+        cli_out ("Common secret pub file present at %s", common_pem_file);
+        ret = 0;
+out:
+        if (fd)
+                close (fd);
+
+        gf_log ("", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+int
+gf_cli_sys_exec_cbk (struct rpc_req *req, struct iovec *iov,
+                     int count, void *myframe)
+{
+        int                     ret     = -1;
+        int                     output_count     = -1;
+        int                     i     = -1;
+        char                   *output  = NULL;
+        char                   *command = NULL;
+        char                    output_name[PATH_MAX] = "";
+        gf_cli_rsp              rsp     = {0, };
+        dict_t                  *dict   = NULL;
+        call_frame_t            *frame  = NULL;
+
+        if (req->rpc_status == -1) {
+                ret = -1;
+                goto out;
+        }
+
+        frame = myframe;
+
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+       }
+
+        dict = dict_new ();
+
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len, &dict);
+
+        if (ret)
+                goto out;
+
+        if (rsp.op_ret) {
+                cli_err ("%s", rsp.op_errstr ? rsp.op_errstr :
+                         "Command failed.");
+                ret = rsp.op_ret;
+                goto out;
+        }
+
+        ret = dict_get_int32 (dict, "output_count", &output_count);
+        if (ret) {
+                cli_out ("Command executed successfully.");
+                ret = 0;
+                goto out;
+        }
+
+        ret = dict_get_str (dict, "command", &command);
+        if (ret) {
+                gf_log ("", GF_LOG_ERROR,
+                        "Unable to get command from dict");
+                goto out;
+        }
+
+        if (!strcmp (command, "gsec_create")) {
+                ret = write_contents_to_common_pem_file (dict, output_count);
+                if (!ret)
+                        goto out;
+        }
+
+        for (i = 1; i <= output_count; i++) {
+                memset (output_name, '\0', sizeof (output_name));
+                snprintf (output_name, sizeof (output_name),
+                          "output_%d", i);
+                ret = dict_get_str (dict, output_name, &output);
+                if (ret) {
+                        gf_log ("", GF_LOG_ERROR, "Failed to get %s.",
+                                output_name);
+                        cli_out ("Unable to fetch output.");
+                }
+                if (output) {
+                        cli_out ("%s", output);
+                        output = NULL;
+                }
+        }
+
+        ret = 0;
+out:
+        if (dict)
+                dict_unref (dict);
+        cli_cmd_broadcast_response (ret);
+
+        free (rsp.dict.dict_val);
+
         return ret;
+}
 
+int
+gf_cli_copy_file_cbk (struct rpc_req *req, struct iovec *iov,
+                      int count, void *myframe)
+{
+        int                     ret     = -1;
+        gf_cli_rsp              rsp     = {0, };
+        dict_t                  *dict   = NULL;
+        call_frame_t            *frame  = NULL;
+
+        if (req->rpc_status == -1) {
+                ret = -1;
+                goto out;
+        }
+
+        frame = myframe;
+
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+       }
+
+        dict = dict_new ();
+
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len, &dict);
+
+       if (ret)
+                goto out;
+
+        if (rsp.op_ret) {
+                cli_err ("%s", rsp.op_errstr ? rsp.op_errstr :
+                         "Copy unsuccessful");
+                ret = rsp.op_ret;
+                goto out;
+        }
+
+        cli_out ("Successfully copied file.");
+
+out:
+        if (dict)
+                dict_unref (dict);
+        cli_cmd_broadcast_response (ret);
+
+        free (rsp.dict.dict_val);
+
+        return ret;
 }
 
 int
@@ -3507,17 +4361,22 @@ gf_cli_gsync_set_cbk (struct rpc_req *req, struct iovec *iov,
         char                    *gsync_status = NULL;
         char                    *master = NULL;
         char                    *slave  = NULL;
-        int32_t                  type    = 0;
+        int32_t                  type   = 0;
+        call_frame_t            *frame  = NULL;
+        gf_boolean_t             status_detail = _gf_false;
+
 
         if (req->rpc_status == -1) {
                 ret = -1;
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR,
-                        "Unable to get response structure");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -3557,7 +4416,7 @@ gf_cli_gsync_set_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_int32 (dict, "type", &type);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "failed to get type");
+                gf_log (frame->this->name, GF_LOG_ERROR, "failed to get type");
                 goto out;
         }
 
@@ -3581,8 +4440,30 @@ gf_cli_gsync_set_cbk (struct rpc_req *req, struct iovec *iov,
                 break;
 
                 case GF_GSYNC_OPTION_TYPE_STATUS:
-                        ret = gf_cli_gsync_out_status (dict);
-                        goto out;
+                        status_detail = dict_get_str_boolean (dict,
+                                                              "status-detail",
+                                                              _gf_false);
+                        ret = gf_cli_gsync_status_output (dict, status_detail);
+                break;
+
+                case GF_GSYNC_OPTION_TYPE_DELETE:
+                        if (dict_get_str (dict, "master", &master) != 0)
+                                master = "???";
+                        if (dict_get_str (dict, "slave", &slave) != 0)
+                                slave = "???";
+                        cli_out ("Deleting " GEOREP " session between %s & %s"
+                                 " has been successful", master, slave);
+                break;
+
+                case GF_GSYNC_OPTION_TYPE_CREATE:
+                        if (dict_get_str (dict, "master", &master) != 0)
+                                master = "???";
+                        if (dict_get_str (dict, "slave", &slave) != 0)
+                                slave = "???";
+                        cli_out ("Creating " GEOREP " session between %s & %s"
+                                 " has been successful", master, slave);
+                break;
+
                 default:
                         cli_out (GEOREP" command executed successfully");
         }
@@ -3598,6 +4479,54 @@ out:
 }
 
 int32_t
+gf_cli_sys_exec (call_frame_t *frame, xlator_t *this, void *data)
+{
+        int                      ret    = 0;
+        dict_t                  *dict   = NULL;
+        gf_cli_req               req = {{0,}};
+
+        if (!frame || !this || !data) {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid data");
+                goto out;
+        }
+
+        dict = data;
+
+        ret = cli_to_glusterd (&req, frame, gf_cli_sys_exec_cbk,
+                               (xdrproc_t) xdr_gf_cli_req, dict,
+                               GLUSTER_CLI_SYS_EXEC, this, cli_rpc_prog,
+                               NULL);
+out:
+        GF_FREE (req.dict.dict_val);
+        return ret;
+}
+
+int32_t
+gf_cli_copy_file (call_frame_t *frame, xlator_t *this, void *data)
+{
+        int                      ret    = 0;
+        dict_t                  *dict   = NULL;
+        gf_cli_req               req = {{0,}};
+
+        if (!frame || !this || !data) {
+                ret = -1;
+                gf_log ("cli", GF_LOG_ERROR, "Invalid data");
+                goto out;
+        }
+
+        dict = data;
+
+        ret = cli_to_glusterd (&req, frame, gf_cli_copy_file_cbk,
+                               (xdrproc_t) xdr_gf_cli_req, dict,
+                               GLUSTER_CLI_COPY_FILE, this, cli_rpc_prog,
+                               NULL);
+out:
+        GF_FREE (req.dict.dict_val);
+        return ret;
+}
+
+int32_t
 gf_cli_gsync_set (call_frame_t *frame, xlator_t *this,
                      void *data)
 {
@@ -3831,7 +4760,8 @@ gf_cli_profile_volume_cbk (struct rpc_req *req, struct iovec *iov,
         gf_log ("cli", GF_LOG_DEBUG, "Received resp to profile");
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -4019,7 +4949,8 @@ gf_cli_top_volume_cbk (struct rpc_req *req, struct iovec *iov,
         gf_log ("cli", GF_LOG_DEBUG, "Received resp to top");
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "Unable to decode response");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -4255,8 +5186,15 @@ gf_cli_getwd_cbk (struct rpc_req *req, struct iovec *iov,
         }
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_getwd_rsp);
-        if (ret < 0 || rsp.op_ret == -1) {
-                gf_log ("", GF_LOG_ERROR, "error");
+        if (ret < 0) {
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        if (rsp.op_ret == -1) {
+                cli_err ("getwd failed");
+                ret = rsp.op_ret;
                 goto out;
         }
 
@@ -5272,6 +6210,123 @@ out:
         return;
 }
 
+static void
+cli_print_volume_status_tasks (dict_t *dict)
+{
+        int             ret         = -1;
+        int             i           = 0;
+        int             j           = 0;
+        int             count       = 0;
+        int             task_count  = 0;
+        int             status      = 0;
+        char           *op          = NULL;
+        char           *task_id_str = NULL;
+        char           *volname     = NULL;
+        char            key[1024]   = {0,};
+        char            task[1024]  = {0,};
+        char           *brick       = NULL;
+        char           *src_brick   = NULL;
+        char           *dest_brick  = NULL;
+
+        ret = dict_get_str (dict, "volname", &volname);
+        if (ret)
+                goto out;
+
+        ret = dict_get_int32 (dict, "tasks", &task_count);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to get tasks count");
+                return;
+        }
+
+        cli_out ("Task Status of Volume %s", volname);
+        cli_print_line (CLI_BRICK_STATUS_LINE_LEN);
+
+        if (task_count == 0) {
+                cli_out ("There are no active volume tasks");
+                cli_out (" ");
+                return;
+        }
+
+        for (i = 0; i < task_count; i++) {
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.type", i);
+                ret = dict_get_str(dict, key, &op);
+                if (ret)
+                        return;
+                cli_out ("%-20s : %-20s", "Task", op);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.id", i);
+                ret = dict_get_str (dict, key, &task_id_str);
+                if (ret)
+                        return;
+                cli_out ("%-20s : %-20s", "ID", task_id_str);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.status", i);
+                ret = dict_get_int32 (dict, key, &status);
+                if (ret)
+                        return;
+
+                snprintf (task, sizeof (task), "task%d", i);
+
+                /*
+                   Replace brick only has two states - In progress and Complete
+                   Ref: xlators/mgmt/glusterd/src/glusterd-replace-brick.c
+                */
+
+                if (!strcmp (op, "Replace brick")) {
+                        if (status)
+                                status = GF_DEFRAG_STATUS_COMPLETE;
+                        else
+                                status = GF_DEFRAG_STATUS_STARTED;
+
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key), "%s.src-brick", task);
+                        ret = dict_get_str (dict, key, &src_brick);
+                        if (ret)
+                                goto out;
+
+                        cli_out ("%-20s : %-20s", "Source Brick", src_brick);
+
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key), "%s.dst-brick", task);
+                        ret = dict_get_str (dict, key, &dest_brick);
+                        if (ret)
+                                goto out;
+
+                        cli_out ("%-20s : %-20s", "Destination Brick",
+                                 dest_brick);
+
+                } else if (!strcmp (op, "Remove brick")) {
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key), "%s.count", task);
+                        ret = dict_get_int32 (dict, key, &count);
+                        if (ret)
+                                goto out;
+
+                        cli_out ("%-20s", "Removed bricks:");
+
+                        for (j = 1; j <= count; j++) {
+                                memset (key, 0, sizeof (key));
+                                snprintf (key, sizeof (key),"%s.brick%d",
+                                          task, j);
+                                ret = dict_get_str (dict, key, &brick);
+                                if (ret)
+                                        goto out;
+
+                                cli_out ("%-20s", brick);
+                        }
+                }
+                cli_out ("%-20s : %-20s", "Status",
+                         cli_vol_task_status_str[status]);
+                cli_out (" ");
+        }
+
+out:
+        return;
+}
+
 static int
 gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
                       int count, void *myframe)
@@ -5300,7 +6355,8 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("cli", GF_LOG_ERROR, "Volume status response error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -5325,10 +6381,12 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
                                   "status information.");
 
                 if (global_state->mode & GLUSTER_MODE_XML) {
-                       cli_xml_output_str ("volStatus", msg, rsp.op_ret,
-                                           rsp.op_errno, rsp.op_errstr);
-                       ret = 0;
-                       goto out;
+                        if (!local->all)
+                                cli_xml_output_str ("volStatus", msg,
+                                                    rsp.op_ret, rsp.op_errno,
+                                                    rsp.op_errstr);
+                        ret = 0;
+                        goto out;
                 }
 
                 cli_err ("%s", msg);
@@ -5370,23 +6428,6 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
         if ((cmd & GF_CLI_STATUS_NFS) || (cmd & GF_CLI_STATUS_SHD))
                 notbrick = _gf_true;
 
-        ret = dict_get_int32 (dict, "count", &count);
-        if (ret)
-                goto out;
-        if (count == 0) {
-                ret = -1;
-                goto out;
-        }
-
-        ret = dict_get_int32 (dict, "brick-index-max", &brick_index_max);
-        if (ret)
-                goto out;
-        ret = dict_get_int32 (dict, "other-count", &other_count);
-        if (ret)
-                goto out;
-
-        index_max = brick_index_max + other_count;
-
         if (global_state->mode & GLUSTER_MODE_XML) {
                 if (!local->all) {
                         ret = cli_xml_output_vol_status_begin (local,
@@ -5399,11 +6440,21 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
                                 goto out;
                         }
                 }
-                ret = cli_xml_output_vol_status (local, dict);
-                if (ret) {
-                        gf_log ("cli", GF_LOG_ERROR,
-                                "Error outputting to xml");
-                        goto out;
+                if (cmd & GF_CLI_STATUS_TASKS) {
+                        ret = cli_xml_output_vol_status_tasks_detail (local,
+                                                                      dict);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR,"Error outputting "
+                                        "to xml");
+                                goto out;
+                        }
+                } else {
+                        ret = cli_xml_output_vol_status (local, dict);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR,
+                                        "Error outputting to xml");
+                                goto out;
+                        }
                 }
 
                 if (!local->all) {
@@ -5439,6 +6490,10 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
                         cli_print_volume_status_callpool (dict, notbrick);
                         goto cont;
                         break;
+                case GF_CLI_STATUS_TASKS:
+                        cli_print_volume_status_tasks (dict);
+                        goto cont;
+                        break;
                 default:
                         break;
         }
@@ -5447,6 +6502,17 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
         if (ret)
                 goto out;
 
+        ret = dict_get_int32 (dict, "brick-index-max", &brick_index_max);
+        if (ret)
+                goto out;
+
+        ret = dict_get_int32 (dict, "other-count", &other_count);
+        if (ret)
+                goto out;
+
+        index_max = brick_index_max + other_count;
+
+
         cli_out ("Status of volume: %s", volname);
 
         if ((cmd & GF_CLI_STATUS_DETAIL) == 0) {
@@ -5518,6 +6584,9 @@ gf_cli_status_cbk (struct rpc_req *req, struct iovec *iov,
                 }
         }
         cli_out (" ");
+
+        if ((cmd & GF_CLI_STATUS_MASK) == GF_CLI_STATUS_NONE)
+                cli_print_volume_status_tasks (dict);
 cont:
         ret = rsp.op_ret;
 
@@ -5593,12 +6662,6 @@ gf_cli_status_volume_all (call_frame_t *frame, xlator_t *this, void *data)
                 goto out;
         }
 
-        if (vol_count == 0) {
-                cli_err ("No volumes present");
-                ret = 0;
-                goto out;
-        }
-
         /* remove the "all" flag in cmd */
         cmd &= ~GF_CLI_STATUS_ALL;
         cmd |= GF_CLI_STATUS_VOL;
@@ -5613,6 +6676,12 @@ gf_cli_status_volume_all (call_frame_t *frame, xlator_t *this, void *data)
                 }
         }
 
+        if (vol_count == 0 && !(global_state->mode & GLUSTER_MODE_XML)) {
+                cli_err ("No volumes present");
+                ret = 0;
+                goto out;
+        }
+
         for (i = 0; i < vol_count; i++) {
 
                 dict = dict_new ();
@@ -5676,7 +6745,8 @@ gf_cli_mount_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_mount_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -5743,7 +6813,8 @@ gf_cli_umount_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf1_cli_umount_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -5793,6 +6864,97 @@ gf_cli_umount (call_frame_t *frame, xlator_t *this, void *data)
 }
 
 void
+cmd_heal_volume_statistics_out (dict_t *dict, int  brick)
+{
+
+        uint64_t        num_entries = 0;
+        int             ret = 0;
+        char            key[256] = {0};
+        char            *hostname = NULL;
+        uint64_t        i = 0;
+        uint64_t        healed_count = 0;
+        uint64_t        split_brain_count = 0;
+        uint64_t        heal_failed_count = 0;
+        char            *start_time_str = NULL;
+        char            *end_time_str = NULL;
+        char            *crawl_type = NULL;
+        int             progress = -1;
+
+        snprintf (key, sizeof key, "%d-hostname", brick);
+        ret = dict_get_str (dict, key, &hostname);
+        if (ret)
+                goto out;
+        cli_out ("------------------------------------------------");
+        cli_out ("\nCrawl statistics for brick no %d", brick);
+        cli_out ("Hostname of brick %s", hostname);
+
+        snprintf (key, sizeof key, "statistics-%d-count", brick);
+        ret = dict_get_uint64 (dict, key, &num_entries);
+        if (ret)
+                goto out;
+
+        for (i = 0; i < num_entries; i++)
+        {
+                snprintf (key, sizeof key, "statistics_crawl_type-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_str (dict, key, &crawl_type);
+                if (ret)
+                        goto out;
+
+                snprintf (key, sizeof key, "statistics_healed_cnt-%d-%"PRIu64,
+                          brick,i);
+                ret = dict_get_uint64 (dict, key, &healed_count);
+                if (ret)
+                        goto out;
+
+                snprintf (key, sizeof key, "statistics_sb_cnt-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_uint64 (dict, key, &split_brain_count);
+                if (ret)
+                        goto out;
+                snprintf (key, sizeof key, "statistics_heal_failed_cnt-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_uint64 (dict, key, &heal_failed_count);
+                if (ret)
+                        goto out;
+                snprintf (key, sizeof key, "statistics_strt_time-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_str (dict, key,  &start_time_str);
+                if (ret)
+                        goto out;
+                snprintf (key, sizeof key, "statistics_end_time-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_str (dict, key, &end_time_str);
+                if (ret)
+                        goto out;
+                snprintf (key, sizeof key, "statistics_inprogress-%d-%"PRIu64,
+                          brick, i);
+                ret = dict_get_int32 (dict, key, &progress);
+                if (ret)
+                        goto out;
+
+                cli_out ("\nStarting time of crawl: %s", start_time_str);
+                if (progress == 1)
+                        cli_out ("Crawl is in progress");
+                else
+                        cli_out ("Ending time of crawl: %s", end_time_str);
+
+                cli_out ("Type of crawl: %s", crawl_type);
+                cli_out ("No. of entries healed: %"PRIu64,
+                         healed_count);
+                cli_out ("No. of entries in split-brain: %"PRIu64,
+                        split_brain_count);
+                cli_out ("No. of heal failed entries: %"PRIu64,
+                         heal_failed_count);
+
+        }
+
+
+out:
+        return;
+}
+
+void
 cmd_heal_volume_brick_out (dict_t *dict, int brick)
 {
         uint64_t        num_entries = 0;
@@ -5804,6 +6966,7 @@ cmd_heal_volume_brick_out (dict_t *dict, int brick)
         uint64_t        i = 0;
         uint32_t        time = 0;
         char            timestr[32] = {0};
+        char            *shd_status = NULL;
 
         snprintf (key, sizeof key, "%d-hostname", brick);
         ret = dict_get_str (dict, key, &hostname);
@@ -5814,37 +6977,96 @@ cmd_heal_volume_brick_out (dict_t *dict, int brick)
         if (ret)
                 goto out;
         cli_out ("\nBrick %s:%s", hostname, path);
-        snprintf (key, sizeof key, "%d-count", brick);
-        ret = dict_get_uint64 (dict, key, &num_entries);
-        cli_out ("Number of entries: %"PRIu64, num_entries);
+
         snprintf (key, sizeof key, "%d-status", brick);
         ret = dict_get_str (dict, key, &status);
         if (status && strlen (status))
                 cli_out ("Status: %s", status);
-        for (i = 0; i < num_entries; i++) {
-                snprintf (key, sizeof key, "%d-%"PRIu64, brick, i);
-                ret = dict_get_str (dict, key, &path);
-                if (ret)
-                        continue;
-                time = 0;
-                snprintf (key, sizeof key, "%d-%"PRIu64"-time", brick, i);
-                ret = dict_get_uint32 (dict, key, &time);
-                if (!time) {
-                        cli_out ("%s", path);
-                } else {
-                        gf_time_fmt (timestr, sizeof timestr,
-                                     time, gf_timefmt_FT);
-                        if (i == 0) {
+
+        snprintf (key, sizeof key, "%d-shd-status",brick);
+        ret = dict_get_str (dict, key, &shd_status);
+
+        if(!shd_status)
+        {
+                snprintf (key, sizeof key, "%d-count", brick);
+                ret = dict_get_uint64 (dict, key, &num_entries);
+                cli_out ("Number of entries: %"PRIu64, num_entries);
+
+
+                for (i = 0; i < num_entries; i++) {
+                        snprintf (key, sizeof key, "%d-%"PRIu64, brick, i);
+                        ret = dict_get_str (dict, key, &path);
+                        if (ret)
+                                continue;
+                        time = 0;
+                        snprintf (key, sizeof key, "%d-%"PRIu64"-time",
+                                  brick, i);
+                        ret = dict_get_uint32 (dict, key, &time);
+                        if (!time) {
+                                cli_out ("%s", path);
+                        } else {
+                                gf_time_fmt (timestr, sizeof timestr,
+                                             time, gf_timefmt_FT);
+                                if (i == 0) {
                                 cli_out ("at                    path on brick");
                                 cli_out ("-----------------------------------");
+                                }
+                                cli_out ("%s %s", timestr, path);
                         }
-                        cli_out ("%s %s", timestr, path);
                 }
         }
+
+out:
+        return;
+}
+
+
+void
+cmd_heal_volume_statistics_heal_count_out (dict_t *dict, int brick)
+{
+        uint64_t        num_entries = 0;
+        int             ret = 0;
+        char            key[256] = {0};
+        char           *hostname = NULL;
+        char           *path = NULL;
+        char           *status = NULL;
+        char            *shd_status = NULL;
+
+        snprintf (key, sizeof key, "%d-hostname", brick);
+        ret = dict_get_str (dict, key, &hostname);
+        if (ret)
+                goto out;
+        snprintf (key, sizeof key, "%d-path", brick);
+        ret = dict_get_str (dict, key, &path);
+        if (ret)
+                goto out;
+        cli_out ("\nBrick %s:%s", hostname, path);
+
+        snprintf (key, sizeof key, "%d-status", brick);
+        ret = dict_get_str (dict, key, &status);
+        if (status && strlen (status))
+                cli_out ("Status: %s", status);
+
+        snprintf (key, sizeof key, "%d-shd-status",brick);
+        ret = dict_get_str (dict, key, &shd_status);
+
+        if(!shd_status)
+        {
+                snprintf (key, sizeof key, "%d-hardlinks", brick);
+                ret = dict_get_uint64 (dict, key, &num_entries);
+                if (ret)
+                        cli_out ("No gathered input for this brick");
+                else
+                        cli_out ("Number of entries: %"PRIu64, num_entries);
+
+
+        }
+
 out:
         return;
 }
 
+
 int
 gf_cli_heal_volume_cbk (struct rpc_req *req, struct iovec *iov,
                              int count, void *myframe)
@@ -5861,19 +7083,21 @@ gf_cli_heal_volume_cbk (struct rpc_req *req, struct iovec *iov,
         gf_xl_afr_op_t          heal_op = GF_AFR_OP_INVALID;
         char                    *operation = NULL;
         char                    *substr = NULL;
+        char                    *heal_op_str = NULL;
 
         if (-1 == req->rpc_status) {
                 goto out;
         }
 
+        frame = myframe;
+
         ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log ("", GF_LOG_ERROR, "error");
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
-        frame = myframe;
-
         if (frame)
                 local = frame->local;
 
@@ -5896,18 +7120,51 @@ gf_cli_heal_volume_cbk (struct rpc_req *req, struct iovec *iov,
 
         ret = dict_get_str (input_dict, "volname", &volname);
         if (ret) {
-                gf_log (THIS->name, GF_LOG_ERROR, "failed to get volname");
+                gf_log (frame->this->name, GF_LOG_ERROR, "failed to get volname");
                 goto out;
         }
 
         gf_log ("cli", GF_LOG_INFO, "Received resp to heal volume");
 
+        switch (heal_op) {
+                case    GF_AFR_OP_HEAL_INDEX:
+                        heal_op_str = "to perform index self heal";
+                        break;
+                case    GF_AFR_OP_HEAL_FULL:
+                        heal_op_str = "to perform full self heal";
+                        break;
+                case    GF_AFR_OP_INDEX_SUMMARY:
+                        heal_op_str = "list of entries to be healed";
+                        break;
+                case    GF_AFR_OP_HEALED_FILES:
+                        heal_op_str = "list of healed entries";
+                        break;
+                case    GF_AFR_OP_HEAL_FAILED_FILES:
+                        heal_op_str = "list of heal failed entries";
+                        break;
+                case    GF_AFR_OP_SPLIT_BRAIN_FILES:
+                        heal_op_str = "list of split brain entries";
+                        break;
+                case    GF_AFR_OP_STATISTICS:
+                        heal_op_str =  "crawl statistics";
+                        break;
+                case    GF_AFR_OP_STATISTICS_HEAL_COUNT:
+                        heal_op_str = "count of entries to be healed";
+                        break;
+                case    GF_AFR_OP_STATISTICS_HEAL_COUNT_PER_REPLICA:
+                        heal_op_str = "count of entries to be healed per replica";
+                        break;
+                case    GF_AFR_OP_INVALID:
+                        heal_op_str = "invalid heal op";
+                        break;
+        }
+
         if ((heal_op == GF_AFR_OP_HEAL_FULL) ||
             (heal_op == GF_AFR_OP_HEAL_INDEX)) {
-                operation = "Launching Heal operation";
+                operation = "Launching heal operation";
                 substr = "\nUse heal info commands to check status";
         } else {
-                operation = "Gathering Heal info";
+                operation = "Gathering";
                 substr = "";
         }
 
@@ -5915,15 +7172,15 @@ gf_cli_heal_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 if (strcmp (rsp.op_errstr, "")) {
                         cli_err ("%s", rsp.op_errstr);
                 } else {
-                        cli_err ("%s on volume %s has been unsuccessful",
-                                 operation, volname);
+                        cli_err ("%s %s on volume %s has been unsuccessful",
+                                 operation, heal_op_str, volname);
                 }
 
                 ret = rsp.op_ret;
                 goto out;
         } else {
-                cli_out ("%s on volume %s has been successful%s", operation,
-                         volname, substr);
+                cli_out ("%s %s on volume %s has been successful %s", operation,
+                         heal_op_str, volname, substr);
         }
 
         ret = rsp.op_ret;
@@ -5957,8 +7214,28 @@ gf_cli_heal_volume_cbk (struct rpc_req *req, struct iovec *iov,
                 goto out;
         }
 
-        for (i = 0; i < brick_count; i++)
-                cmd_heal_volume_brick_out (dict, i);
+        switch (heal_op) {
+                case GF_AFR_OP_STATISTICS:
+                        for (i = 0; i < brick_count; i++)
+                                cmd_heal_volume_statistics_out (dict, i);
+                        break;
+                case GF_AFR_OP_STATISTICS_HEAL_COUNT:
+                case GF_AFR_OP_STATISTICS_HEAL_COUNT_PER_REPLICA:
+                        for (i = 0; i < brick_count; i++)
+                                cmd_heal_volume_statistics_heal_count_out (dict,
+                                                                           i);
+                        break;
+                case GF_AFR_OP_INDEX_SUMMARY:
+                case GF_AFR_OP_HEALED_FILES:
+                case GF_AFR_OP_HEAL_FAILED_FILES:
+                case GF_AFR_OP_SPLIT_BRAIN_FILES:
+                        for (i = 0; i < brick_count; i++)
+                                cmd_heal_volume_brick_out (dict, i);
+                        break;
+                default:
+                        break;
+        }
+
         ret = rsp.op_ret;
 
 out:
@@ -6010,7 +7287,8 @@ gf_cli_statedump_volume_cbk (struct rpc_req *req, struct iovec *iov,
         ret = xdr_to_generic (*iov, &rsp,
                               (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log (THIS->name, GF_LOG_ERROR, "XDR decoding failed");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
         gf_log ("cli", GF_LOG_DEBUG, "Received response to statedump");
@@ -6081,7 +7359,8 @@ gf_cli_list_volume_cbk (struct rpc_req *req, struct iovec *iov,
         ret = xdr_to_generic (*iov, &rsp,
                               (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-                gf_log (THIS->name, GF_LOG_ERROR, "XDR decoding failed");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
 
@@ -6168,8 +7447,8 @@ gf_cli_clearlocks_volume_cbk (struct rpc_req *req, struct iovec *iov,
         ret = xdr_to_generic (*iov, &rsp,
                               (xdrproc_t)xdr_gf_cli_rsp);
         if (ret < 0) {
-
-                gf_log ("cli", GF_LOG_ERROR, "XDR decoding failed");
+                gf_log (((call_frame_t *) myframe)->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
                 goto out;
         }
         gf_log ("cli", GF_LOG_DEBUG, "Received response to clear-locks");
@@ -6253,6 +7532,1024 @@ out:
         return ret;
 }
 
+int32_t
+cli_snapshot_remove_reply (gf_cli_rsp *rsp, dict_t *dict, call_frame_t *frame)
+{
+        int32_t       ret        = -1;
+        char         *snap_name  = NULL;
+
+        GF_ASSERT (rsp);
+        GF_ASSERT (dict);
+        GF_ASSERT (frame);
+
+        if (rsp->op_ret) {
+                cli_err("snapshot delete: failed: %s",
+                        rsp->op_errstr ? rsp->op_errstr :
+                        "Please check log file for details");
+                ret = rsp->op_ret;
+                goto out;
+        }
+
+        ret = dict_get_str (dict, "snapname", &snap_name);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to get snapname");
+                goto out;
+        }
+
+        cli_out ("snapshot delete: %s: snap removed successfully",
+                 snap_name);
+        ret = 0;
+
+out:
+        return ret;
+}
+
+int
+cli_snapshot_config_display (dict_t *dict, gf_cli_rsp *rsp)
+{
+        char                buf[PATH_MAX]        = "";
+        char               *volname              = NULL;
+        int                 ret                  = -1;
+        int                 config_command       = 0;
+        uint64_t            value                = 0;
+        uint64_t            hard_limit           = 0;
+        uint64_t            soft_limit           = 0;
+        uint64_t            i                    = 0;
+        uint64_t            voldisplaycount      = 0;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (rsp);
+
+        if (rsp->op_ret) {
+                cli_err ("Snapshot Config : failed: %s",
+                         rsp->op_errstr ? rsp->op_errstr :
+                         "Please check log file for details");
+                ret = rsp->op_ret;
+                goto out;
+        }
+
+        ret = dict_get_int32 (dict, "config-command", &config_command);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch config type");
+                goto out;
+        }
+
+        ret = dict_get_str (dict, "volname", &volname);
+        /* Ignore the error, as volname is optional */
+
+        if (!volname) {
+                volname = "System";
+        }
+
+        ret = dict_get_uint64 (dict, "snap-max-hard-limit", &hard_limit);
+        /* Ignore the error, as the key specified is optional */
+        ret = dict_get_uint64 (dict, "snap-max-soft-limit", &soft_limit);
+
+        if (!hard_limit && !soft_limit
+                        && config_command != GF_SNAP_CONFIG_DISPLAY) {
+                ret = -1;
+                gf_log(THIS->name, GF_LOG_ERROR,
+                       "Could not fetch config-key");
+                goto out;
+        }
+
+        switch (config_command) {
+        case GF_SNAP_CONFIG_TYPE_SET:
+                if (hard_limit && soft_limit) {
+                        cli_out ("snapshot config: snap-max-hard-limit "
+                                "& snap-max-soft-limit for system set "
+                                 "successfully");
+                } else if (hard_limit){
+                        cli_out ("snapshot config: %s "
+                                 "for snap-max-hard-limit set successfully",
+                                 volname);
+                } else if (soft_limit) {
+                        cli_out ("snapshot config: %s "
+                                 "for snap-max-soft-limit set successfully",
+                                 volname);
+                }
+                break;
+
+        case GF_SNAP_CONFIG_DISPLAY :
+                cli_out ("\nSnapshot System Configuration:");
+                ret = dict_get_uint64 (dict, "snap-max-hard-limit",
+                                       &value);
+                if (ret) {
+                         gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                "snap_max_hard_limit for %s", volname);
+                         ret = -1;
+                         goto out;
+                }
+                cli_out ("snap-max-hard-limit : %"PRIu64, value);
+
+                ret = dict_get_uint64 (dict, "snap-max-soft-limit",
+                                       &soft_limit);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                               "snap-max-soft-limit for %s", volname);
+                        ret = -1;
+                        goto out;
+                }
+                cli_out ("snap-max-soft-limit : %"PRIu64"%%\n",
+                         soft_limit);
+
+                cli_out ("Snapshot Volume Configuration:");
+
+                ret = dict_get_uint64 (dict, "voldisplaycount",
+                                       &voldisplaycount);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                               "Could not fetch voldisplaycount");
+                        ret = -1;
+                        goto out;
+                }
+
+                for (i = 0; i < voldisplaycount; i++) {
+                        snprintf (buf, sizeof(buf), "volume%ld-volname", i);
+                        ret = dict_get_str (dict, buf, &volname);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                       " %s", buf);
+                                ret = -1;
+                                goto out;
+                        }
+                        cli_out ("\nVolume : %s", volname);
+
+                        snprintf (buf, sizeof(buf),
+                                  "volume%ld-snap-max-hard-limit", i);
+                        ret = dict_get_uint64 (dict, buf, &value);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                       " %s", buf);
+                                ret = -1;
+                                goto out;
+                        }
+                        cli_out ("snap-max-hard-limit : %"PRIu64, value);
+
+                        snprintf (buf, sizeof(buf),
+                                  "volume%ld-active-hard-limit", i);
+                        ret = dict_get_uint64 (dict, buf, &value);
+                        if (ret) {
+                                 gf_log ("cli", GF_LOG_ERROR, "Could not fetch"
+                                        " effective snap_max_hard_limit for "
+                                        "%s", volname);
+                                ret = -1;
+                                goto out;
+                        }
+                        cli_out ("Effective snap-max-hard-limit : %"PRIu64,
+                                 value);
+
+                        snprintf (buf, sizeof(buf),
+                                      "volume%ld-snap-max-soft-limit", i);
+                        ret = dict_get_uint64 (dict, buf, &value);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                       " %s", buf);
+                                ret = -1;
+                                goto out;
+                        }
+                        cli_out ("Effective snap-max-soft-limit : %"PRIu64" "
+                                 "(%"PRIu64"%%)", value, soft_limit);
+                }
+                break;
+        default :
+                break;
+        }
+
+        ret = 0;
+out:
+        return ret;
+}
+
+/* This function is used to print the volume related information
+ * of a snap.
+ *
+ * arg - 0, dict       : Response Dictionary.
+ * arg - 1, prefix str : snaplist.snap{0..}.vol{0..}.*
+ */
+int
+cli_get_each_volinfo_in_snap (dict_t *dict, char *keyprefix,
+                              gf_boolean_t snap_driven) {
+        char             key[PATH_MAX]  =  "";
+        char            *get_buffer     =  NULL;
+        int              value          =  0;
+        int              ret            = -1;
+        char             indent[5]      = "\t";
+        char            *volname        =  NULL;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (keyprefix);
+
+        if (snap_driven) {
+                ret = snprintf (key, sizeof (key), "%s.volname", keyprefix);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &get_buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to get %s", key);
+                        goto out;
+                }
+                cli_out ("%s" INDENT_MAIN_HEAD "%s", indent,
+                        "Snap Volume Name", ":", get_buffer);
+
+                ret = snprintf (key, sizeof (key),
+                                "%s.origin-volname", keyprefix);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &volname);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_WARNING, "Failed to get %s", key);
+                        cli_out ("%-12s", "Origin:");
+                }
+                cli_out ("%s" INDENT_MAIN_HEAD "%s", indent,
+                        "Origin Volume name", ":", volname);
+
+
+                ret = snprintf (key, sizeof (key), "%s.snapcount",
+                                keyprefix);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_int32 (dict, key, &value);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to get %s", key);
+                        goto out;
+                }
+                cli_out ("%s%s %s      %s %d", indent, "Snaps taken for",
+                        volname, ":", value);
+
+                ret = snprintf (key, sizeof (key), "%s.snaps-available",
+                                keyprefix);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_int32 (dict, key, &value);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to get %s", key);
+                        goto out;
+                }
+                cli_out ("%s%s %s  %s %d", indent, "Snaps available for",
+                         volname, ":", value);
+        }
+
+
+        ret = snprintf (key, sizeof (key), "%s.vol-status", keyprefix);
+        if (ret < 0) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to get %s", key);
+                goto out;
+        }
+        cli_out ("%s" INDENT_MAIN_HEAD "%s", indent, "Status",
+                 ":", get_buffer);
+out :
+        return ret;
+}
+
+/* This function is used to print snap related information
+ * arg - 0, dict       : Response dictionary.
+ * arg - 1, prefix_str : snaplist.snap{0..}.*
+ */
+int
+cli_get_volinfo_in_snap (dict_t *dict, char *keyprefix) {
+
+        char            key[PATH_MAX]   = "";
+        int             i               = 0;
+        int             volcount        = 0;
+        int             ret             = -1;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (keyprefix);
+
+        ret = snprintf (key, sizeof (key), "%s.vol-count", keyprefix);
+        if (ret < 0) {
+                goto out;
+        }
+
+        ret = dict_get_int32 (dict, key, &volcount);
+        for (i = 1 ; i <= volcount ; i++) {
+                ret = snprintf (key, sizeof (key),
+                                "%s.vol%d", keyprefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+                ret = cli_get_each_volinfo_in_snap (dict, key, _gf_true);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not list "
+                                "details of volume in a snap");
+                        goto out;
+                }
+                cli_out (" ");
+        }
+
+out :
+        return ret;
+}
+
+int
+cli_get_each_snap_info (dict_t *dict, char *prefix_str,
+                        gf_boolean_t snap_driven) {
+        char            key_buffer[PATH_MAX] = "";
+        char           *get_buffer           = NULL;
+        int             ret                  = -1;
+        char            indent[5]            = "";
+
+        GF_ASSERT (dict);
+        GF_ASSERT (prefix_str);
+
+        if (!snap_driven)
+                strcat (indent, "\t");
+
+        ret = snprintf (key_buffer, sizeof (key_buffer), "%s.snapname",
+                        prefix_str);
+        if (ret < 0 ) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key_buffer, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to fetch snapname %s ",
+                        key_buffer);
+                goto out;
+        }
+        cli_out ("%s" INDENT_MAIN_HEAD "%s", indent, "Snapshot",
+                ":", get_buffer);
+
+        ret = snprintf (key_buffer, sizeof (key_buffer), "%s.snap-id",
+                        prefix_str);
+        if (ret < 0 ) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key_buffer, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to fetch snap-id %s ",
+                        key_buffer);
+                goto out;
+        }
+        cli_out ("%s" INDENT_MAIN_HEAD "%s", indent, "Snap UUID",
+                ":", get_buffer);
+
+        ret = snprintf (key_buffer, sizeof (key_buffer), "%s.snap-desc",
+                        prefix_str);
+        if (ret < 0 ) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key_buffer, &get_buffer);
+        if (!ret) {
+                /* Ignore error for description */
+                cli_out ("%s" INDENT_MAIN_HEAD "%s", indent,
+                         "Description", ":", get_buffer);
+        }
+
+        ret = snprintf (key_buffer, sizeof (key_buffer), "%s.snap-time",
+                        prefix_str);
+        if (ret < 0 ) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key_buffer, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to fetch snap-time %s ",
+                        prefix_str);
+                goto out;
+        }
+        cli_out ("%s" INDENT_MAIN_HEAD "%s", indent, "Created",
+                ":", get_buffer);
+
+        if (snap_driven) {
+                cli_out ("%-12s", "Snap Volumes:\n");
+                ret = cli_get_volinfo_in_snap (dict, prefix_str);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Unable to list details "
+                                "of the snaps");
+                        goto out;
+                }
+        }
+out :
+        return ret;
+}
+
+/* This is a generic function to print snap related information.
+ * arg - 0, dict : Response Dictionary
+ */
+int
+cli_call_snapshot_info (dict_t *dict, gf_boolean_t bool_snap_driven) {
+        int             snap_count       =  0;
+        char            key[PATH_MAX]    =  "";
+        int             ret              =  -1;
+        int             i                =   0;
+
+        GF_ASSERT (dict);
+
+        ret = dict_get_int32 (dict, "snap-count", &snap_count);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to get snap-count");
+                goto out;
+        }
+
+        if (snap_count == 0) {
+                cli_out ("No snapshots present");
+        }
+
+        for (i = 1 ; i <= snap_count ; i++) {
+                ret = snprintf (key, sizeof (key), "snap%d", i);
+                if (ret < 0) {
+                        goto out;
+                }
+                ret = cli_get_each_snap_info (dict, key, bool_snap_driven);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Unable to print snap details");
+                        goto out;
+                }
+        }
+out :
+        return ret;
+}
+
+int
+cli_get_snaps_in_volume (dict_t *dict) {
+        int      ret             =  -1;
+        int      i               =  0;
+        int      count           =  0;
+        int      avail           =  0;
+        char     key[PATH_MAX]   =  "";
+        char    *get_buffer      =  NULL;
+
+        GF_ASSERT (dict);
+
+        ret = dict_get_str (dict, "origin-volname", &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch origin-volname");
+                goto out;
+        }
+        cli_out (INDENT_MAIN_HEAD "%s", "Volume Name", ":", get_buffer);
+
+        ret = dict_get_int32 (dict, "snap-count", &avail);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch snap-count");
+                goto out;
+        }
+        cli_out (INDENT_MAIN_HEAD "%d", "Snaps Taken", ":", avail);
+
+        ret = dict_get_int32 (dict, "snaps-available", &count);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch snaps-available");
+                goto out;
+        }
+        cli_out (INDENT_MAIN_HEAD "%d", "Snaps Available", ":", count);
+
+        for (i = 1 ; i <= avail ; i++) {
+                snprintf (key, sizeof (key), "snap%d", i);
+                ret = cli_get_each_snap_info (dict, key, _gf_false);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Unable to print snap details");
+                        goto out;
+                }
+
+                ret = snprintf (key, sizeof (key), "snap%d.vol1", i);
+                if (ret < 0) {
+                        goto out;
+                }
+                ret = cli_get_each_volinfo_in_snap (dict, key, _gf_false);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not get volume "
+                                "related information");
+                        goto out;
+                }
+
+                cli_out (" ");
+        }
+out :
+        return ret;
+}
+
+int
+cli_snapshot_list (dict_t *dict) {
+        int     snapcount       =       0;
+        char    key[PATH_MAX]   =       "";
+        int     ret             =       -1;
+        int     i               =       0;
+        char    *get_buffer     =       NULL;
+
+        GF_ASSERT (dict);
+
+        ret = dict_get_int32 (dict, "snap-count", &snapcount);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch snap count");
+                goto out;
+        }
+
+        if (snapcount == 0) {
+                cli_out ("No snapshots present");
+        }
+
+        for (i = 1 ; i <= snapcount ; i++) {
+                ret = snprintf (key, sizeof (key), "snapname%d",i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &get_buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not get %s ", key);
+                        goto out;
+                } else {
+                        cli_out ("%s", get_buffer);
+                }
+        }
+out :
+        return ret;
+}
+
+int
+cli_get_snap_volume_status (dict_t *dict, char *key_prefix)
+{
+        int             ret             =       -1;
+        char            key[PATH_MAX]   =       "";
+        char            *buffer         =       NULL;
+        int             brickcount      =       0;
+        int             i               =       0;
+        int             pid             =       0;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (key_prefix);
+
+        ret = snprintf (key, sizeof (key), "%s.brickcount", key_prefix);
+        if (ret < 0) {
+                goto out;
+        }
+        ret = dict_get_int32 (dict, key, &brickcount);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Failed to fetch brickcount");
+                goto out;
+        }
+
+        for ( i = 0 ; i < brickcount ; i++ ) {
+                ret = snprintf (key, sizeof (key), "%s.brick%d.path",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO,
+                                "Unable to get Brick Path");
+                        continue;
+                }
+                cli_out ("\n\t%-17s %s   %s", "Brick Path", ":", buffer);
+
+                ret = snprintf (key, sizeof (key), "%s.brick%d.vgname",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO,
+                                "Unable to get Volume Group");
+                        cli_out ("\t%-17s %s   %s", "Volume Group", ":", "N/A");
+                } else
+                        cli_out ("\t%-17s %s   %s", "Volume Group", ":", buffer);
+
+                ret = snprintf (key, sizeof (key), "%s.brick%d.status",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO,
+                                "Unable to get Brick Running");
+                        cli_out ("\t%-17s %s   %s", "Brick Running", ":", "N/A");
+                } else
+                        cli_out ("\t%-17s %s   %s", "Brick Running", ":", buffer);
+
+                ret = snprintf (key, sizeof (key), "%s.brick%d.pid",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_int32 (dict, key, &pid);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO,
+                                "Unable to get pid");
+                        cli_out ("\t%-17s %s   %s", "Brick PID", ":", "N/A");
+                } else
+                        cli_out ("\t%-17s %s   %d", "Brick PID", ":", pid);
+
+                ret = snprintf (key, sizeof (key), "%s.brick%d.data",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = dict_get_str (dict, key, &buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO,
+                                "Unable to get Data Percent");
+                        cli_out ("\t%-17s %s   %s", "Data Percentage", ":", "N/A");
+                } else
+                        cli_out ("\t%-17s %s   %s", "Data Percentage", ":", buffer);
+
+                ret = snprintf (key, sizeof (key), "%s.brick%d.lvsize",
+                                key_prefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+                ret = dict_get_str (dict, key, &buffer);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_INFO, "Unable to get LV Size");
+                        cli_out ("\t%-17s %s   %s", "LV Size", ":", "N/A");
+                } else
+                        cli_out ("\t%-17s %s   %s", "LV Size", ":", buffer);
+
+        }
+out :
+        return ret;
+}
+
+
+
+int
+cli_get_single_snap_status (dict_t *dict, char *keyprefix)
+{
+        int             ret             =       -1;
+        char            key[PATH_MAX]   =       "";
+        int             i               =       0;
+        int             volcount        =       0;
+        char            *get_buffer     =       NULL;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (keyprefix);
+
+        ret = snprintf (key, sizeof (key), "%s.snapname", keyprefix);
+        if (ret < 0) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to get snapname");
+                goto out;
+        }
+        cli_out ("\nSnap Name : %s", get_buffer);
+
+        ret = snprintf (key, sizeof (key), "%s.uuid", keyprefix);
+        if (ret < 0) {
+                goto out;
+        }
+
+        ret = dict_get_str (dict, key, &get_buffer);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to get snap UUID");
+                goto out;
+        }
+        cli_out ("Snap UUID : %s", get_buffer);
+
+        ret = snprintf (key, sizeof (key), "%s.volcount", keyprefix);
+        if (ret < 0) {
+                goto out;
+        }
+
+        ret = dict_get_int32 (dict, key, &volcount);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Unable to get volume count");
+                goto out;
+        }
+
+        for (i = 0 ; i < volcount ; i++) {
+                ret = snprintf (key, sizeof (key), "%s.vol%d", keyprefix, i);
+                if (ret < 0) {
+                        goto out;
+                }
+
+                ret = cli_get_snap_volume_status (dict, key);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Could not get snap volume status");
+                        goto out;
+                }
+        }
+out :
+        return ret;
+}
+
+int
+cli_snap_status_all (dict_t *dict) {
+        int             ret             =       -1;
+        char            key[PATH_MAX]   =       "";
+        int             snapcount       =       0;
+        int             i               =       0;
+
+        GF_ASSERT (dict);
+
+        ret = dict_get_int32 (dict, "status.snapcount", &snapcount);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not get snapcount");
+                goto out;
+        }
+
+        if (snapcount == 0) {
+                cli_out ("No snapshots present");
+        }
+
+        for (i = 0 ; i < snapcount; i++) {
+                ret = snprintf (key, sizeof (key), "status.snap%d",i);
+                if (ret < 0) {
+                        goto out;
+                }
+                ret = cli_get_single_snap_status (dict, key);
+        }
+out:
+        return ret;
+}
+
+
+int
+cli_snapshot_status_display (dict_t *dict, gf_cli_rsp *rsp)
+{
+        char            key[PATH_MAX]   =       "";
+        int             ret             =       -1;
+        int             status_cmd      =       -1;
+
+        GF_ASSERT (dict);
+        GF_ASSERT (rsp);
+
+        if (rsp->op_ret) {
+                cli_err ("Snapshot Status : failed: %s",
+                        rsp->op_errstr ? rsp->op_errstr :
+                        "Please check log file for details");
+                ret = rsp->op_ret;
+                goto out;
+        }
+
+        ret = dict_get_int32 (dict, "cmd", &status_cmd);
+        if (ret) {
+                gf_log ("cli", GF_LOG_ERROR, "Could not fetch status type");
+                goto out;
+        }
+        switch (status_cmd) {
+                case GF_SNAP_STATUS_TYPE_ALL :
+                {
+                        ret = cli_snap_status_all (dict);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                        "status of all snap");
+                                goto out;
+                        }
+                break;
+                }
+
+                case GF_SNAP_STATUS_TYPE_SNAP :
+                {
+                        ret = snprintf (key, sizeof (key), "status.snap0");
+                        if (ret < 0) {
+                                goto out;
+                        }
+                        ret = cli_get_single_snap_status (dict, key);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                        "status of snap");
+                                goto out;
+                        }
+                break;
+                }
+
+                case GF_SNAP_STATUS_TYPE_VOL :
+                {
+                        ret = cli_snap_status_all (dict);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR, "Could not fetch "
+                                        "status of snap in a volume");
+                                goto out;
+                        }
+                        break;
+                }
+                default :
+                        break;
+        }
+out :
+        return ret;
+}
+
+int
+gf_cli_snapshot_cbk (struct rpc_req *req, struct iovec *iov,
+                     int count, void *myframe)
+{
+        int                   ret                      = -1;
+        gf_cli_rsp            rsp                      = {0, };
+        dict_t               *dict                     = NULL;
+        char                 *snap_name                = NULL;
+        int32_t               type                     =  0;
+        call_frame_t         *frame                    = NULL;
+        gf_boolean_t         snap_driven               = _gf_false;
+
+        if (req->rpc_status == -1) {
+                ret = -1;
+                goto out;
+        }
+
+        frame = myframe;
+
+        ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_cli_rsp);
+        if (ret < 0) {
+                gf_log (frame->this->name, GF_LOG_ERROR,
+                        "Failed to decode xdr response");
+                goto out;
+        }
+
+        dict = dict_new ();
+
+        if (!dict) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = dict_unserialize (rsp.dict.dict_val, rsp.dict.dict_len, &dict);
+
+        if (ret)
+                goto out;
+
+        ret = dict_get_int32 (dict, "type", &type);
+        if (ret) {
+                gf_log (frame->this->name, GF_LOG_ERROR, "failed to get type");
+                goto out;
+        }
+
+        switch (type) {
+        case GF_SNAP_OPTION_TYPE_CREATE:
+                if (rsp.op_ret) {
+                        cli_err("snapshot create: failed: %s",
+                                 rsp.op_errstr ? rsp.op_errstr :
+                                 "Please check log file for details");
+                                 ret = rsp.op_ret;
+                                 goto out;
+                }
+
+                ret = dict_get_str (dict, "snapname", &snap_name);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Failed to get snap name");
+                        goto out;
+                }
+                cli_out ("snapshot create: %s: snap created successfully",
+                         snap_name);
+                break;
+
+        case GF_SNAP_OPTION_TYPE_RESTORE:
+                /* TODO: Check if rsp.op_ret needs to be checked here. Or is
+                 * it ok to check this in the start of the function where we
+                 * get rsp.*/
+                if (rsp.op_ret) {
+                        cli_err("snapshot restore: failed: %s",
+                                 rsp.op_errstr ? rsp.op_errstr :
+                                 "Please check log file for details");
+                                 ret = rsp.op_ret;
+                                 goto out;
+                }
+
+                ret = dict_get_str (dict, "snapname", &snap_name);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Failed to get snap name");
+                        goto out;
+                }
+
+                cli_out ("Snapshot restore: %s: Snap restored "
+                                 "successfully", snap_name);
+
+                ret = 0;
+                break;
+
+        case GF_SNAP_OPTION_TYPE_INFO:
+                if (rsp.op_ret) {
+                        cli_err ("Snapshot info : failed: %s",
+                                  rsp.op_errstr ? rsp.op_errstr :
+                                  "Please check log file for details");
+                        ret = rsp.op_ret;
+                        goto out;
+                }
+
+                snap_driven = dict_get_str_boolean (dict, "snap-driven",
+                                                    _gf_false);
+                if (snap_driven == _gf_true) {
+                        ret = cli_call_snapshot_info  (dict, snap_driven);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR,
+                                        "Snapshot info failed");
+                                goto out;
+                        }
+                } else if (snap_driven == _gf_false) {
+                        ret = cli_get_snaps_in_volume (dict);
+                        if (ret) {
+                                gf_log ("cli", GF_LOG_ERROR,
+                                        "Snapshot info failed");
+                                goto out;
+                        }
+                }
+                break;
+
+        case GF_SNAP_OPTION_TYPE_CONFIG:
+                ret = cli_snapshot_config_display (dict, &rsp);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to display "
+                                "snapshot config output.");
+                        goto out;
+                }
+                break;
+
+        case GF_SNAP_OPTION_TYPE_LIST:
+                if (rsp.op_ret) {
+                        cli_err ("Snapshot list : failed: %s",
+                                 rsp.op_errstr ? rsp.op_errstr :
+                                "Please check log file for details");
+                        ret = rsp.op_ret;
+                        goto out;
+                }
+
+                ret = cli_snapshot_list (dict);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to display "
+                                "snapshot list");
+                        goto out;
+                }
+                break;
+
+        case GF_SNAP_OPTION_TYPE_DELETE:
+                ret = cli_snapshot_remove_reply (&rsp, dict, frame);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR,
+                                "Failed to delete snap");
+                        goto out;
+                }
+                break;
+
+        case GF_SNAP_OPTION_TYPE_STATUS:
+                ret = cli_snapshot_status_display (dict, &rsp);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Failed to display "
+                                "snapshot status output.");
+                        goto out;
+                }
+                break;
+
+        default:
+                cli_err ("Unknown command executed");
+                ret = -1;
+                goto out;
+        }
+out:
+        if (dict)
+                dict_unref (dict);
+        cli_cmd_broadcast_response (ret);
+
+        free (rsp.dict.dict_val);
+        free (rsp.op_errstr);
+
+        return ret;
+}
+
+int32_t
+gf_cli_snapshot (call_frame_t *frame, xlator_t *this,
+                 void *data)
+{
+        gf_cli_req        req     = {{0,}};
+        dict_t           *options = NULL;
+        int               ret     = -1;
+
+        if (!frame || !this || !data)
+                goto out;
+
+        options = data;
+
+        ret = cli_to_glusterd (&req, frame, gf_cli_snapshot_cbk,
+                               (xdrproc_t) xdr_gf_cli_req, options,
+                               GLUSTER_CLI_SNAP, this, cli_rpc_prog,
+                               NULL);
+out:
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+
+        GF_FREE (req.dict.dict_val);
+        return ret;
+}
+
 int
 cli_to_glusterd (gf_cli_req *req, call_frame_t *frame,
                  fop_cbk_fn_t cbkfn, xdrproc_t xdrproc, dict_t *dict,
@@ -6330,6 +8627,7 @@ struct rpc_clnt_procedure gluster_cli_actors[GLUSTER_CLI_MAXVALUE] = {
         [GLUSTER_CLI_DEPROBE]          = {"DEPROBE_QUERY", gf_cli_deprobe},
         [GLUSTER_CLI_LIST_FRIENDS]     = {"LIST_FRIENDS", gf_cli_list_friends},
         [GLUSTER_CLI_UUID_RESET]       = {"UUID_RESET", gf_cli3_1_uuid_reset},
+        [GLUSTER_CLI_UUID_GET]       = {"UUID_GET", gf_cli3_1_uuid_get},
         [GLUSTER_CLI_CREATE_VOLUME]    = {"CREATE_VOLUME", gf_cli_create_volume},
         [GLUSTER_CLI_DELETE_VOLUME]    = {"DELETE_VOLUME", gf_cli_delete_volume},
         [GLUSTER_CLI_START_VOLUME]     = {"START_VOLUME", gf_cli_start_volume},
@@ -6361,9 +8659,9 @@ struct rpc_clnt_procedure gluster_cli_actors[GLUSTER_CLI_MAXVALUE] = {
         [GLUSTER_CLI_STATEDUMP_VOLUME] = {"STATEDUMP_VOLUME", gf_cli_statedump_volume},
         [GLUSTER_CLI_LIST_VOLUME]      = {"LIST_VOLUME", gf_cli_list_volume},
         [GLUSTER_CLI_CLRLOCKS_VOLUME]  = {"CLEARLOCKS_VOLUME", gf_cli_clearlocks_volume},
-#ifdef HAVE_BD_XLATOR
-        [GLUSTER_CLI_BD_OP]            = {"BD_OP", gf_cli_bd_op},
-#endif
+        [GLUSTER_CLI_COPY_FILE]        = {"COPY_FILE", gf_cli_copy_file},
+        [GLUSTER_CLI_SYS_EXEC]         = {"SYS_EXEC", gf_cli_sys_exec},
+        [GLUSTER_CLI_SNAP]             = {"SNAP", gf_cli_snapshot},
 };
 
 struct rpc_clnt_program cli_prog = {
diff --git a/cli/src/cli-xml-output.c b/cli/src/cli-xml-output.c
index 3e8bbdd4f..d8884d44b 100644
--- a/cli/src/cli-xml-output.c
+++ b/cli/src/cli-xml-output.c
@@ -15,6 +15,39 @@
 #include "syscall.h"
 
 
+enum gf_task_types {
+    GF_TASK_TYPE_REBALANCE,
+    GF_TASK_TYPE_REMOVE_BRICK
+};
+
+/*
+ * IMPORTANT NOTE:
+ * All exported functions in this file which use libxml need use a
+ * #if (HAVE_LIB_XML), #else, #endif
+ * For eg,
+ *      int exported_func () {
+ *              #if (HAVE_LIB_XML)
+ *                      <Stuff using libxml>
+ *              #else
+ *                      return 0;
+ *              #endif
+ *      }
+ *
+ *  All other functions, which are called internally within this file need to be
+ *  within #if (HAVE_LIB_XML), #endif statements
+ *  For eg,
+ *      #if (HAVE_LIB_XML)
+ *      int internal_func ()
+ *      {
+ *      }
+ *      #endif
+ *
+ *  Following the above formate ensures that all xml related code is compliled
+ *  only when libxml2 is present, and also keeps the rest of the codebase free
+ *  of #if (HAVE_LIB_XML)
+ */
+
+
 #if (HAVE_LIB_XML)
 
 #include <libxml/encoding.h>
@@ -30,18 +63,11 @@
         }while (0)                                              \
 
 int
-cli_begin_xml_output (xmlTextWriterPtr *writer, xmlBufferPtr *buf)
+cli_begin_xml_output (xmlTextWriterPtr *writer, xmlDocPtr *doc)
 {
         int             ret = -1;
 
-        *buf = xmlBufferCreateSize (8192);
-        if (*buf == NULL) {
-                ret = -1;
-                goto out;
-        }
-        xmlBufferSetAllocationScheme (*buf, XML_BUFFER_ALLOC_DOUBLEIT);
-
-        *writer = xmlNewTextWriterMemory (*buf, 0);
+        *writer = xmlNewTextWriterDoc (doc, 0);
         if (writer == NULL) {
                 ret = -1;
                 goto out;
@@ -60,7 +86,7 @@ out:
 }
 
 int
-cli_end_xml_output (xmlTextWriterPtr writer, xmlBufferPtr buf)
+cli_end_xml_output (xmlTextWriterPtr writer, xmlDocPtr doc)
 {
         int             ret = -1;
 
@@ -71,10 +97,12 @@ cli_end_xml_output (xmlTextWriterPtr writer, xmlBufferPtr buf)
         ret = xmlTextWriterEndDocument (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        cli_out ("%s", (const char *)buf->content);
+
+        /* Dump xml document to stdout and pretty format it */
+        xmlSaveFormatFileEnc ("-", doc, "UTF-8", 1);
 
         xmlFreeTextWriter (writer);
-        xmlBufferFree (buf);
+        xmlFreeDoc (doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -96,7 +124,7 @@ cli_xml_output_common (xmlTextWriterPtr writer, int op_ret, int op_errno,
         XML_RET_CHECK_AND_GOTO (ret, out);
 
         ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"opErrstr",
-                                               "%s", op_errstr);
+                                                "%s", op_errstr);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
 out:
@@ -112,9 +140,9 @@ cli_xml_output_str (char *op, char *str, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -122,15 +150,21 @@ cli_xml_output_str (char *op, char *str, int op_ret, int op_errno,
         if (ret)
                 goto out;
 
-        ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"cliOp",
-                                               "%s", op);
-        XML_RET_CHECK_AND_GOTO (ret, out);
+        if (op) {
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"cliOp",
+                                                       "%s", op);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
 
-        ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"output",
-                                               "%s", str);
-        XML_RET_CHECK_AND_GOTO (ret, out);
+        if (str) {
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"output",
+                                                       "%s", str);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -164,9 +198,9 @@ cli_xml_output_dict ( char *op, dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -185,7 +219,7 @@ cli_xml_output_dict ( char *op, dict_t *dict, int op_ret, int op_errno,
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
@@ -1306,7 +1340,7 @@ cli_xml_output_vol_status_begin (cli_local_t *local, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
 
-        ret = cli_begin_xml_output (&(local->writer), &(local->buf));
+        ret = cli_begin_xml_output (&(local->writer), &(local->doc));
         XML_RET_CHECK_AND_GOTO (ret, out);
 
         ret = cli_xml_output_common (local->writer, op_ret, op_errno,
@@ -1344,7 +1378,7 @@ cli_xml_output_vol_status_end (cli_local_t *local)
         ret = xmlTextWriterEndElement (local->writer);
         XML_RET_CHECK_AND_GOTO(ret, out);
 
-        ret = cli_end_xml_output (local->writer, local->buf);
+        ret = cli_end_xml_output (local->writer, local->doc);
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
@@ -1353,6 +1387,215 @@ out:
 #endif
 }
 
+#if (HAVE_LIB_XML)
+int
+cli_xml_output_remove_brick_task_params (xmlTextWriterPtr writer, dict_t *dict,
+                                         char *prefix)
+{
+        int             ret = -1;
+        char            key[1024] = {0,};
+        int             count = 0;
+        int             i = 0;
+        char            *brick = NULL;
+
+        /* <params> */
+        ret = xmlTextWriterStartElement (writer, (xmlChar *)"params");
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        snprintf (key, sizeof (key), "%s.count", prefix);
+        ret = dict_get_int32 (dict, key, &count);
+        if (ret)
+                goto out;
+
+        for (i = 1; i <= count; i++) {
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "%s.brick%d", prefix, i);
+                ret = dict_get_str (dict, key, &brick);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"brick",
+                                                       "%s", brick);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+                brick = NULL;
+        }
+
+        /* </param> */
+        ret = xmlTextWriterEndElement (writer);
+
+out:
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+int
+cli_xml_output_replace_brick_task_params (xmlTextWriterPtr writer, dict_t *dict,
+                                          char *prefix)
+{
+
+        int             ret = -1;
+        char            key[1024] = {0,};
+        char            *brick = NULL;
+
+        /* <params> */
+        ret = xmlTextWriterStartElement (writer, (xmlChar *)"params");
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        snprintf (key, sizeof (key), "%s.src-brick", prefix);
+        ret = dict_get_str (dict, key, &brick);
+        if (ret)
+                goto out;
+        ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"srcBrick",
+                                               "%s", brick);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+
+        memset (key, 0, sizeof (key));
+        snprintf (key, sizeof (key), "%s.dst-brick", prefix);
+        ret = dict_get_str (dict, key, &brick);
+        if (ret)
+                goto out;
+        ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"dstBrick",
+                                               "%s", brick);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+
+        /* </param> */
+        ret = xmlTextWriterEndElement (writer);
+
+out:
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+int
+cli_xml_output_vol_status_tasks (cli_local_t *local, dict_t *dict) {
+        int                     ret = -1;
+        char                    *task_type = NULL;
+        char                    *task_id_str = NULL;
+        int                     status = 0;
+        int                     tasks = 0;
+        char                    key[1024] = {0,};
+        int                     i = 0;
+
+        /* <tasks> */
+        ret = xmlTextWriterStartElement (local->writer, (xmlChar *)"tasks");
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = dict_get_int32 (dict, "tasks", &tasks);
+        if (ret)
+                goto out;
+
+        for (i = 0; i < tasks; i++) {
+                /* <task> */
+                ret = xmlTextWriterStartElement (local->writer,
+                                                 (xmlChar *)"task");
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.type", i);
+                ret = dict_get_str (dict, key, &task_type);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (local->writer,
+                                                       (xmlChar *)"type",
+                                                       "%s", task_type);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.id", i);
+                ret = dict_get_str (dict, key, &task_id_str);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (local->writer,
+                                                       (xmlChar *)"id",
+                                                       "%s", task_id_str);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d.status", i);
+                ret = dict_get_int32 (dict, key, &status);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (local->writer,
+                                                       (xmlChar *)"status",
+                                                       "%d", status);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                if (!strcmp (task_type, "Replace brick")) {
+                    if (status) {
+                        status = GF_DEFRAG_STATUS_COMPLETE;
+                    } else {
+                        status = GF_DEFRAG_STATUS_STARTED;
+                    }
+                }
+
+                ret = xmlTextWriterWriteFormatElement (local->writer,
+                                                       (xmlChar *)"statusStr",
+                                                       "%s",
+                                             cli_vol_task_status_str[status]);
+
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "task%d", i);
+                if (!strcmp (task_type, "Replace brick")) {
+                        ret = cli_xml_output_replace_brick_task_params
+                                (local->writer, dict, key);
+                        if (ret)
+                                goto out;
+                } else if (!strcmp (task_type, "Remove brick")) {
+                        ret = cli_xml_output_remove_brick_task_params
+                                (local->writer, dict, key);
+                        if (ret)
+                                goto out;
+                }
+
+
+                /* </task> */
+                ret = xmlTextWriterEndElement (local->writer);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
+
+        /* </tasks> */
+        ret = xmlTextWriterEndElement (local->writer);
+
+out:
+        gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
+        return ret;
+}
+
+int
+cli_xml_output_vol_status_tasks_detail (cli_local_t *local, dict_t *dict)
+{
+        int    ret     = -1;
+        char  *volname = NULL;
+
+        /*<volume>*/
+        ret = xmlTextWriterStartElement (local->writer, (xmlChar *)"volume");
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = dict_get_str (dict, "volname", &volname);
+        if (ret)
+                goto out;
+        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                               (xmlChar *)"volName", "%s",
+                                               volname);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = cli_xml_output_vol_status_tasks (local, dict);
+        if (ret)
+                goto out;
+
+        /* </volume> */
+        ret = xmlTextWriterEndElement (local->writer);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+out:
+        return ret;
+}
+#endif
+
 int
 cli_xml_output_vol_status (cli_local_t *local, dict_t *dict)
 {
@@ -1470,7 +1713,6 @@ cli_xml_output_vol_status (cli_local_t *local, dict_t *dict)
                                         goto out;
                         }
                         break;
-
                 default:
                         break;
 
@@ -1480,6 +1722,16 @@ cli_xml_output_vol_status (cli_local_t *local, dict_t *dict)
                 XML_RET_CHECK_AND_GOTO (ret, out);
         }
 
+        /* Tasks are only present when a normal volume status call is done on a
+         * single volume or on all volumes
+         */
+        if (((cmd & GF_CLI_STATUS_MASK) == GF_CLI_STATUS_NONE) &&
+            (cmd & (GF_CLI_STATUS_VOL|GF_CLI_STATUS_ALL))) {
+                ret = cli_xml_output_vol_status_tasks (local, dict);
+                if (ret)
+                        goto out;
+        }
+
         /* </volume> */
         ret = xmlTextWriterEndElement (local->writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
@@ -1606,7 +1858,7 @@ cli_xml_output_vol_top (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         int                     brick_count = 0;
         int                     top_op = GF_CLI_TOP_NONE;
         char                    *brick_name = NULL;
@@ -1620,7 +1872,7 @@ cli_xml_output_vol_top (dict_t *dict, int op_ret, int op_errno,
         int                     i = 0;
         int                     j = 0;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -1709,8 +1961,6 @@ cli_xml_output_vol_top (dict_t *dict, int op_ret, int op_errno,
                 case GF_CLI_TOP_WRITE:
                 case GF_CLI_TOP_OPENDIR:
                 case GF_CLI_TOP_READDIR:
-                        if (!members)
-                                continue;
 
                         break;
 
@@ -1736,9 +1986,6 @@ cli_xml_output_vol_top (dict_t *dict, int op_ret, int op_errno,
                                          "%f", time_taken);
                         }
 
-                        if (!members)
-                                continue;
-
                         break;
 
                 default:
@@ -1768,7 +2015,7 @@ cli_xml_output_vol_top (dict_t *dict, int op_ret, int op_errno,
         /* </volTop> */
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -1963,7 +2210,7 @@ cli_xml_output_vol_profile (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         char                    *volname = NULL;
         int                     op = GF_CLI_STATS_NONE;
         int                     brick_count = 0;
@@ -1972,7 +2219,7 @@ cli_xml_output_vol_profile (dict_t *dict, int op_ret, int op_errno,
         char                    key[1024] = {0,};
         int                     i = 0;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2052,7 +2299,7 @@ cont:
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
@@ -2068,13 +2315,13 @@ cli_xml_output_vol_list (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         int                     count = 0;
         char                    *volname = NULL;
         char                    key[1024] = {0,};
         int                     i = 0;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2109,7 +2356,7 @@ cli_xml_output_vol_list (dict_t *dict, int op_ret, int op_errno,
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
@@ -2163,15 +2410,44 @@ out:
         return ret;
 }
 
+struct tmp_xml_option_logger {
+        char *key;
+        xmlTextWriterPtr writer;
+};
+
+static int
+_output_vol_info_option (dict_t *d, char *k, data_t *v,
+                         void *data)
+{
+        int                           ret   = 0;
+        char                         *ptr   = NULL;
+        struct tmp_xml_option_logger *tmp   = NULL;
+
+        tmp = data;
+
+        ptr = strstr (k, "option.");
+        if (!ptr)
+                goto out;
+
+        if (!v) {
+                ret = -1;
+                goto out;
+        }
+        ret = cli_xml_output_vol_info_option (tmp->writer, tmp->key, k,
+                                              v->data);
+
+out:
+        return ret;
+}
+
 int
 cli_xml_output_vol_info_options (xmlTextWriterPtr writer, dict_t *dict,
                                  char *prefix)
 {
         int             ret = -1;
         int             opt_count = 0;
-        data_t          *value = 0;
-        char            *ptr = NULL;
         char            key[1024] = {0,};
+        struct tmp_xml_option_logger tmp = {0,};
 
         snprintf (key, sizeof (key), "%s.opt_count", prefix);
         ret = dict_get_int32 (dict, key, &opt_count);
@@ -2186,26 +2462,9 @@ cli_xml_output_vol_info_options (xmlTextWriterPtr writer, dict_t *dict,
         XML_RET_CHECK_AND_GOTO (ret, out);
         snprintf (key, sizeof (key), "%s.option.", prefix);
 
-        int _output_vol_info_option (dict_t *d, char *k, data_t *v,
-                                     void *data)
-        {
-                int ret = 0;
-                ptr = strstr (k, "option.");
-                if (!ptr)
-                        goto internal_out;
-
-                value = v;
-                if (!value) {
-                        ret = -1;
-                        goto internal_out;
-                }
-                ret = cli_xml_output_vol_info_option (writer, key, k,
-                                                      v->data);
-
-        internal_out:
-                return ret;
-        }
-        ret = dict_foreach (dict, _output_vol_info_option, NULL);
+        tmp.key = key;
+        tmp.writer = writer;
+        ret = dict_foreach (dict, _output_vol_info_option, &tmp);
         if (ret)
                 goto out;
 
@@ -2226,6 +2485,7 @@ cli_xml_output_vol_info (cli_local_t *local, dict_t *dict)
         int                     count = 0;
         char                    *volname = NULL;
         char                    *volume_id = NULL;
+        char                    *uuid = NULL;
         int                     type = 0;
         int                     status = 0;
         int                     brick_count = 0;
@@ -2237,7 +2497,9 @@ cli_xml_output_vol_info (cli_local_t *local, dict_t *dict)
         char                    key[1024] = {0,};
         int                     i = 0;
         int                     j = 1;
-
+        char                    *caps = NULL;
+        int                     k __attribute__((unused)) = 0;
+        char                    *snap_volume = NULL;
 
         ret = dict_get_int32 (dict, "count", &count);
         if (ret)
@@ -2279,6 +2541,18 @@ cli_xml_output_vol_info (cli_local_t *local, dict_t *dict)
                                                        "%d", status);
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "volume%d.snap_volume", i);
+                ret = dict_get_str (dict, key, &snap_volume);
+                if (ret)
+                        goto out;
+                if (snap_volume) {
+                        ret = xmlTextWriterWriteFormatElement (local->writer,
+                                                         (xmlChar *)"snapVol",
+                                                          "%s", snap_volume);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+                }
+
                 ret =xmlTextWriterWriteFormatElement
                         (local->writer, (xmlChar *)"statusStr", "%s",
                          cli_vol_status_str[status]);
@@ -2353,20 +2627,95 @@ cli_xml_output_vol_info (cli_local_t *local, dict_t *dict)
                                                        "%d", transport);
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
+#ifdef HAVE_BD_XLATOR
+                /* <xlators> */
+                ret = xmlTextWriterStartElement (local->writer,
+                                                 (xmlChar *)"xlators");
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                for (k = 0; ; k++) {
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key),"volume%d.xlator%d", i, k);
+                        ret = dict_get_str (dict, key, &caps);
+                        if (ret)
+                                break;
+
+                        /* <xlator> */
+                        ret = xmlTextWriterStartElement (local->writer,
+                                                         (xmlChar *)"xlator");
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
+                        ret = xmlTextWriterWriteFormatElement
+                                (local->writer, (xmlChar *)"name", "%s", caps);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
+                        /* <capabilities> */
+                        ret = xmlTextWriterStartElement (local->writer,
+                                                         (xmlChar *)
+                                                         "capabilities");
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
+                        j = 0;
+                        for (j = 0; ;j++) {
+                                memset (key, 0, sizeof (key));
+                                snprintf (key, sizeof (key),
+                                          "volume%d.xlator%d.caps%d", i, k, j);
+                                ret = dict_get_str (dict, key, &caps);
+                                if (ret)
+                                        break;
+                                ret = xmlTextWriterWriteFormatElement
+                                        (local->writer, (xmlChar *)"capability",
+                                         "%s", caps);
+                                XML_RET_CHECK_AND_GOTO (ret, out);
+                        }
+                        /* </capabilities> */
+                        ret = xmlTextWriterEndElement (local->writer);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+                        /* </xlator> */
+                        ret = xmlTextWriterEndElement (local->writer);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+                }
+                ret = xmlTextWriterFullEndElement (local->writer);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+                /* </xlators> */
+#else
+                caps = 0; /* Avoid compiler warnings when BD not enabled */
+#endif
+                j = 1;
+
                 /* <bricks> */
                 ret = xmlTextWriterStartElement (local->writer,
                                                  (xmlChar *)"bricks");
                 XML_RET_CHECK_AND_GOTO (ret, out);
                 while (j <= brick_count) {
+                        ret = xmlTextWriterStartElement
+                                (local->writer, (xmlChar *)"brick");
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
+                        memset (key, 0, sizeof (key));
+                        snprintf (key, sizeof (key), "volume%d.brick%d.uuid",
+                                  i, j);
+                        ret = dict_get_str (dict, key, &uuid);
+                        if (ret)
+                                goto out;
+                        ret = xmlTextWriterWriteFormatAttribute
+                                (local->writer, (xmlChar *)"uuid", "%s",
+                                 uuid);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
                         memset (key, 0, sizeof (key));
                         snprintf (key, sizeof (key), "volume%d.brick%d", i, j);
                         ret = dict_get_str (dict, key, &brick);
                         if (ret)
                                 goto out;
-                        ret = xmlTextWriterWriteFormatElement
-                                (local->writer, (xmlChar *)"brick", "%s",
-                                 brick);
+                        ret = xmlTextWriterWriteFormatString
+                                (local->writer, "%s", brick);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+
+                        /* </brick> */
+                        ret = xmlTextWriterEndElement (local->writer);
                         XML_RET_CHECK_AND_GOTO (ret, out);
+
                         j++;
                 }
                 /* </bricks> */
@@ -2384,12 +2733,12 @@ cli_xml_output_vol_info (cli_local_t *local, dict_t *dict)
                 ret = xmlTextWriterEndElement (local->writer);
                 XML_RET_CHECK_AND_GOTO (ret, out);
         }
-        GF_FREE (local->get_vol.volname);
+
         if (volname) {
+                GF_FREE (local->get_vol.volname);
                 local->get_vol.volname = gf_strdup (volname);
                 local->vol_count += count;
         }
-
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
@@ -2407,7 +2756,7 @@ cli_xml_output_vol_info_begin (cli_local_t *local, int op_ret, int op_errno,
 
         GF_ASSERT (local);
 
-        ret = cli_begin_xml_output (&(local->writer), &(local->buf));
+        ret = cli_begin_xml_output (&(local->writer), &(local->doc));
         if (ret)
                 goto out;
 
@@ -2455,7 +2804,7 @@ cli_xml_output_vol_info_end (cli_local_t *local)
         ret = xmlTextWriterEndElement (local->writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (local->writer, local->buf);
+        ret = cli_end_xml_output (local->writer, local->doc);
 
 out:
         gf_log ("cli", GF_LOG_ERROR, "Returning %d", ret);
@@ -2473,7 +2822,7 @@ cli_xml_output_vol_quota_limit_list (char *volname, char *limit_list,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         int64_t                 size = 0;
         int64_t                 limit_value = 0;
         int                     i = 0;
@@ -2491,7 +2840,7 @@ cli_xml_output_vol_quota_limit_list (char *volname, char *limit_list,
         GF_ASSERT (volname);
         GF_ASSERT (limit_list);
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2601,7 +2950,7 @@ cont:
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         GF_FREE (size_str);
@@ -2619,18 +2968,17 @@ cli_xml_output_peer_status (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         int                     count = 0;
         char                    *uuid = NULL;
         char                    *hostname = NULL;
         int                     connected = 0;
         int                     state_id = 0;
         char                    *state_str = NULL;
-        int                     port = 0;
         int                     i = 1;
         char                    key[1024] = {0,};
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2690,34 +3038,23 @@ cli_xml_output_peer_status (dict_t *dict, int op_ret, int op_errno,
                 memset (key, 0, sizeof (key));
                 snprintf (key, sizeof (key), "friend%d.stateId", i);
                 ret = dict_get_int32 (dict, key, &state_id);
-                if (ret)
-                        goto out;
+                if (!ret) {
+                        /* ignore */
 
-                ret = xmlTextWriterWriteFormatElement (writer,
-                                                       (xmlChar *)"state",
-                                                       "%d", state_id);
-                XML_RET_CHECK_AND_GOTO (ret, out);
+                        ret = xmlTextWriterWriteFormatElement (writer,
+                                           (xmlChar *)"state", "%d", state_id);
+                        XML_RET_CHECK_AND_GOTO (ret, out);
+                }
 
                 memset (key, 0, sizeof (key));
                 snprintf (key, sizeof (key), "friend%d.state", i);
                 ret = dict_get_str (dict, key, &state_str);
-                if (ret)
-                        goto out;
+                if (!ret) {
+                        /* ignore */
 
-                ret = xmlTextWriterWriteFormatElement (writer,
-                                                       (xmlChar *)"stateStr",
-                                                       "%s", state_str);
-                XML_RET_CHECK_AND_GOTO (ret, out);
-
-                memset (key, 0, sizeof (key));
-                snprintf (key, sizeof (key), "friend%d.port", i);
-                ret = dict_get_int32 (dict, key, &port);
-                if (port != 0) {
-                        ret = xmlTextWriterWriteFormatElement
-                                (writer, (xmlChar *)"port", "%d", port);
+                        ret = xmlTextWriterWriteFormatElement (writer,
+                                       (xmlChar *)"stateStr", "%s", state_str);
                         XML_RET_CHECK_AND_GOTO (ret, out);
-
-                        port = 0;
                 }
 
                 /* </peer> */
@@ -2732,7 +3069,7 @@ cont:
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -2745,22 +3082,29 @@ out:
 #if (HAVE_LIB_XML)
 /* Used for rebalance stop/status, remove-brick status */
 int
-cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict)
+cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict,
+                                     enum gf_task_types task_type)
 {
         int                     ret = -1;
         int                     count = 0;
         char                    *node_name = NULL;
+        char                    *node_uuid = NULL;
         uint64_t                files = 0;
         uint64_t                size = 0;
         uint64_t                lookups = 0;
         int                     status_rcd = 0;
         uint64_t                failures = 0;
+        uint64_t                skipped = 0;
         uint64_t                total_files = 0;
         uint64_t                total_size = 0;
         uint64_t                total_lookups = 0;
         uint64_t                total_failures = 0;
+        uint64_t                total_skipped = 0;
         char                    key[1024] = {0,};
         int                     i = 0;
+        int                     overall_status = -1;
+        double                  elapsed = 0;
+        double                  overall_elapsed = 0;
 
         if (!dict) {
                 ret = 0;
@@ -2782,13 +3126,22 @@ cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict)
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
                 memset (key, 0, sizeof (key));
-                snprintf (key, sizeof (key), "node-uuid-%d", i);
+                snprintf (key, sizeof (key), "node-name-%d", i);
                 ret = dict_get_str (dict, key, &node_name);
                 if (ret)
                         goto out;
                 ret = xmlTextWriterWriteFormatElement (writer,
                                                        (xmlChar *)"nodeName",
                                                        "%s", node_name);
+
+                memset (key, 0, sizeof (key));
+                snprintf (key, sizeof (key), "node-uuid-%d", i);
+                ret = dict_get_str (dict, key, &node_uuid);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"id",
+                                                       "%s", node_uuid);
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
                 memset (key, 0, sizeof (key));
@@ -2835,6 +3188,27 @@ cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict)
                                                        "%"PRIu64, failures);
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
+                /* skipped-%d is not available for remove brick in dict,
+                   so using failures as skipped count in case of remove-brick
+                   similar to logic used in CLI(non xml output) */
+                if (task_type == GF_TASK_TYPE_REBALANCE) {
+                    memset (key, 0, sizeof (key));
+                    snprintf (key, sizeof (key), "skipped-%d", i);
+                }
+                else {
+                    memset (key, 0, sizeof (key));
+                    snprintf (key, sizeof (key), "failures-%d", i);
+                }
+
+                ret = dict_get_uint64 (dict, key, &skipped);
+                if (ret)
+                        goto out;
+                total_skipped += skipped;
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"skipped",
+                                                       "%"PRIu64, skipped);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
                 memset (key, 0, sizeof (key));
                 snprintf (key, sizeof (key), "status-%d", i);
                 ret = dict_get_int32 (dict, key, &status_rcd);
@@ -2845,6 +3219,33 @@ cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict)
                                                        "%d", status_rcd);
                 XML_RET_CHECK_AND_GOTO (ret, out);
 
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"statusStr",
+                                                       "%s",
+                                         cli_vol_task_status_str[status_rcd]);
+
+                memset (key, 0, 256);
+                snprintf (key, 256, "run-time-%d", i);
+                ret = dict_get_double (dict, key, &elapsed);
+                if (ret)
+                        goto out;
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"runtime",
+                                                       "%.2f", elapsed);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
+                if (elapsed > overall_elapsed) {
+                    overall_elapsed = elapsed;
+                }
+
+                if (-1 == overall_status)
+                        overall_status = status_rcd;
+                else if ((GF_DEFRAG_STATUS_COMPLETE == overall_status ||
+                          status_rcd > overall_status) &&
+                         (status_rcd != GF_DEFRAG_STATUS_COMPLETE))
+                        overall_status = status_rcd;
+                XML_RET_CHECK_AND_GOTO (ret, out);
+
                 /* </node> */
                 ret = xmlTextWriterEndElement (writer);
                 XML_RET_CHECK_AND_GOTO (ret, out);
@@ -2871,7 +3272,22 @@ cli_xml_output_vol_rebalance_status (xmlTextWriterPtr writer, dict_t *dict)
                                                "%"PRIu64, total_failures);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        // TODO : Aggregate status
+        ret = xmlTextWriterWriteFormatElement (writer,(xmlChar *)"skipped",
+                                               "%"PRIu64, total_skipped);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (writer,(xmlChar *)"status",
+                                               "%d", overall_status);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (writer,(xmlChar *)"statusStr",
+                                               "%s",
+                                      cli_vol_task_status_str[overall_status]);
+        XML_RET_CHECK_AND_GOTO (ret, out);
+
+        ret = xmlTextWriterWriteFormatElement (writer,(xmlChar *)"runtime",
+                                               "%.2f", overall_elapsed);
+        XML_RET_CHECK_AND_GOTO (ret, out);
 
         /* </aggregate> */
         ret = xmlTextWriterEndElement (writer);
@@ -2890,9 +3306,10 @@ cli_xml_output_vol_rebalance (gf_cli_defrag_type op, dict_t *dict, int op_ret,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
+        char                    *task_id_str = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2904,12 +3321,21 @@ cli_xml_output_vol_rebalance (gf_cli_defrag_type op, dict_t *dict, int op_ret,
         ret = xmlTextWriterStartElement (writer, (xmlChar *)"volRebalance");
         XML_RET_CHECK_AND_GOTO (ret, out);
 
+        ret = dict_get_str (dict, GF_REBALANCE_TID_KEY, &task_id_str);
+        if (ret == 0) {
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"task-id",
+                                                       "%s", task_id_str);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
+
         ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"op",
                                                "%d", op);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
         if ((GF_DEFRAG_CMD_STOP == op) || (GF_DEFRAG_CMD_STATUS == op)) {
-                ret = cli_xml_output_vol_rebalance_status (writer, dict);
+                ret = cli_xml_output_vol_rebalance_status (writer, dict,
+                                                      GF_TASK_TYPE_REBALANCE);
                 if (ret)
                         goto out;
         }
@@ -2919,7 +3345,7 @@ cli_xml_output_vol_rebalance (gf_cli_defrag_type op, dict_t *dict, int op_ret,
         XML_RET_CHECK_AND_GOTO (ret, out);
 
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -2936,9 +3362,10 @@ cli_xml_output_vol_remove_brick (gf_boolean_t status_op, dict_t *dict,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
+        char                    *task_id_str = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2950,8 +3377,17 @@ cli_xml_output_vol_remove_brick (gf_boolean_t status_op, dict_t *dict,
         ret = xmlTextWriterStartElement (writer, (xmlChar *)"volRemoveBrick");
         XML_RET_CHECK_AND_GOTO (ret, out);
 
+        ret = dict_get_str (dict, GF_REMOVE_BRICK_TID_KEY, &task_id_str);
+        if (ret == 0) {
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"task-id",
+                                                       "%s", task_id_str);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
+
         if (status_op) {
-                ret = cli_xml_output_vol_rebalance_status (writer, dict);
+                ret = cli_xml_output_vol_rebalance_status (writer, dict,
+                                                   GF_TASK_TYPE_REMOVE_BRICK);
                 if (ret)
                         goto out;
         }
@@ -2961,7 +3397,7 @@ cli_xml_output_vol_remove_brick (gf_boolean_t status_op, dict_t *dict,
         XML_RET_CHECK_AND_GOTO (ret, out);
 
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -2980,10 +3416,11 @@ cli_xml_output_vol_replace_brick (gf1_cli_replace_op op, dict_t *dict,
         int                     status = 0;
         uint64_t                files = 0;
         char                    *current_file = 0;
+        char                    *task_id_str = NULL;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -2995,6 +3432,14 @@ cli_xml_output_vol_replace_brick (gf1_cli_replace_op op, dict_t *dict,
         ret = xmlTextWriterStartElement (writer, (xmlChar *)"volReplaceBrick");
         XML_RET_CHECK_AND_GOTO (ret, out);
 
+        ret = dict_get_str (dict, GF_REPLACE_BRICK_TID_KEY, &task_id_str);
+        if (ret == 0) {
+                ret = xmlTextWriterWriteFormatElement (writer,
+                                                       (xmlChar *)"task-id",
+                                                       "%s", task_id_str);
+                XML_RET_CHECK_AND_GOTO (ret, out);
+        }
+
         ret = xmlTextWriterWriteFormatElement (writer, (xmlChar *)"op",
                                                "%d", op);
         XML_RET_CHECK_AND_GOTO (ret, out);
@@ -3032,7 +3477,7 @@ cont:
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -3049,11 +3494,11 @@ cli_xml_output_vol_create (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         char                    *volname = NULL;
         char                    *volid = NULL;
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -3095,7 +3540,7 @@ cli_xml_output_vol_create (dict_t *dict, int op_ret, int op_errno,
                 XML_RET_CHECK_AND_GOTO (ret, out);
         }
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -3112,13 +3557,13 @@ cli_xml_output_generic_volume (char *op, dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         char                    *volname = NULL;
         char                    *volid = NULL;
 
         GF_ASSERT (op);
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -3159,7 +3604,7 @@ cli_xml_output_generic_volume (char *op, dict_t *dict, int op_ret, int op_errno,
                 XML_RET_CHECK_AND_GOTO (ret, out);
         }
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 
 out:
         gf_log ("cli", GF_LOG_DEBUG, "Returning %d", ret);
@@ -3169,6 +3614,7 @@ out:
 #endif
 }
 
+#if (HAVE_LIB_XML)
 int
 cli_xml_output_vol_gsync_status (dict_t *dict, xmlTextWriterPtr writer)
 {
@@ -3244,6 +3690,7 @@ out:
         gf_log ("cli",GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
 }
+#endif
 
 int
 cli_xml_output_vol_gsync (dict_t *dict, int op_ret, int op_errno,
@@ -3252,15 +3699,14 @@ cli_xml_output_vol_gsync (dict_t *dict, int op_ret, int op_errno,
 #if (HAVE_LIB_XML)
         int                     ret = -1;
         xmlTextWriterPtr        writer = NULL;
-        xmlBufferPtr            buf = NULL;
+        xmlDocPtr               doc = NULL;
         char                    *master = NULL;
         char                    *slave = NULL;
-
-        int             type = 0;
+        int                     type = 0;
 
         GF_ASSERT (dict);
 
-        ret = cli_begin_xml_output (&writer, &buf);
+        ret = cli_begin_xml_output (&writer, &doc);
         if (ret)
                 goto out;
 
@@ -3316,7 +3762,7 @@ cli_xml_output_vol_gsync (dict_t *dict, int op_ret, int op_errno,
         ret = xmlTextWriterEndElement (writer);
         XML_RET_CHECK_AND_GOTO (ret, out);
 
-        ret = cli_end_xml_output (writer, buf);
+        ret = cli_end_xml_output (writer, doc);
 out:
         gf_log ("cli",GF_LOG_DEBUG, "Returning %d", ret);
         return ret;
diff --git a/cli/src/cli.c b/cli/src/cli.c
index 7788ce389..91b315ff1 100644
--- a/cli/src/cli.c
+++ b/cli/src/cli.c
@@ -168,7 +168,8 @@ logging_init (glusterfs_ctx_t *ctx, struct cli_state *state)
         char *log_file = state->log_file ? state->log_file :
                          DEFAULT_CLI_LOG_FILE_DIRECTORY "/cli.log";
 
-        if (gf_log_init (ctx, log_file) == -1) {
+        /* passing ident as NULL means to use default ident for syslog */
+        if (gf_log_init (ctx, log_file, NULL) == -1) {
                 fprintf (stderr, "ERROR: failed to open logfile %s\n",
                          log_file);
                 return -1;
@@ -298,7 +299,17 @@ cli_opt_parse (char *opt, struct cli_state *state)
                 return 1;
 
         if (strcmp (opt, "version") == 0) {
-                puts (argp_program_version);
+                cli_out ("%s", argp_program_version);
+                exit (0);
+        }
+
+        if (strcmp (opt, "print-logdir") == 0) {
+                cli_out ("%s", DEFAULT_LOG_FILE_DIRECTORY);
+                exit (0);
+        }
+
+        if (strcmp (opt, "print-statedumpdir") == 0) {
+                cli_out ("%s", DEFAULT_VAR_RUN_DIRECTORY);
                 exit (0);
         }
 
@@ -342,6 +353,12 @@ cli_opt_parse (char *opt, struct cli_state *state)
                 return 0;
         }
 
+        oarg = strtail (opt, "glusterd-sock=");
+        if (oarg) {
+                state->glusterd_sock = oarg;
+                return 0;
+        }
+
         return -1;
 }
 
@@ -377,6 +394,8 @@ parse_cmdline (int argc, char *argv[], struct cli_state *state)
                 }
         }
 
+        state->argv[state->argc] = NULL;
+
         return ret;
 }
 
@@ -401,7 +420,6 @@ cli_state_init (struct cli_state *state)
         int                   ret = 0;
 
 
-        state->remote_host = "localhost";
         state->log_level = -1;
 
         tree = &state->tree;
@@ -488,23 +506,46 @@ cli_rpc_init (struct cli_state *state)
         if (!options)
                 goto out;
 
-        ret = dict_set_str (options, "remote-host", state->remote_host);
-        if (ret)
-                goto out;
+        /* Connect using to glusterd using the specified method, giving
+         * preference to unix socket connection. If nothing is specified connect
+         * to the default glusterd socket
+         */
+        if (state->glusterd_sock) {
+                gf_log ("cli", GF_LOG_INFO, "Connecting to glusterd using "
+                        "sockfile %s", state->glusterd_sock);
+                ret = rpc_transport_unix_options_build (&options,
+                                                        state->glusterd_sock,
+                                                        0);
+                if (ret)
+                        goto out;
+        } else if (state->remote_host) {
+                gf_log ("cli", GF_LOG_INFO, "Connecting to remote glusterd at "
+                        "%s", state->remote_host);
+                ret = dict_set_str (options, "remote-host", state->remote_host);
+                if (ret)
+                        goto out;
 
-        if (state->remote_port)
-                port = state->remote_port;
+                if (state->remote_port)
+                        port = state->remote_port;
 
-        ret = dict_set_int32 (options, "remote-port", port);
-        if (ret)
-                goto out;
+                ret = dict_set_int32 (options, "remote-port", port);
+                if (ret)
+                        goto out;
 
-        ret = dict_set_str (options, "transport.address-family", "inet");
-        if (ret)
-                goto out;
+                ret = dict_set_str (options, "transport.address-family",
+                                    "inet");
+                if (ret)
+                        goto out;
+        } else {
+                gf_log ("cli", GF_LOG_DEBUG, "Connecting to glusterd using "
+                        "default socket");
+                ret = rpc_transport_unix_options_build
+                        (&options, DEFAULT_GLUSTERD_SOCKFILE, 0);
+                if (ret)
+                        goto out;
+        }
 
         rpc = rpc_clnt_new (options, this->ctx, this->name, 16);
-
         if (!rpc)
                 goto out;
 
@@ -514,7 +555,7 @@ cli_rpc_init (struct cli_state *state)
                 goto out;
         }
 
-        rpc_clnt_start (rpc);
+        ret = rpc_clnt_start (rpc);
 out:
         if (ret) {
                 if (rpc)
@@ -560,7 +601,9 @@ main (int argc, char *argv[])
         if (!ctx)
                 return ENOMEM;
 
+#ifdef DEBUG
         gf_mem_acct_enable_set (ctx);
+#endif
 
         ret = glusterfs_globals_init (ctx);
         if (ret)
diff --git a/cli/src/cli.h b/cli/src/cli.h
index 6e05e0996..8daa4b741 100644
--- a/cli/src/cli.h
+++ b/cli/src/cli.h
@@ -18,6 +18,7 @@
 #include "rpc-clnt.h"
 #include "glusterfs.h"
 #include "protocol-common.h"
+#include "logging.h"
 
 #include "cli1-xdr.h"
 
@@ -30,26 +31,12 @@
 #define CLI_GLUSTERD_PORT                  24007
 #define CLI_DEFAULT_CONN_TIMEOUT             120
 #define CLI_DEFAULT_CMD_TIMEOUT              120
-#define CLI_TOP_CMD_TIMEOUT                  600 //Longer timeout for volume top
+#define CLI_TEN_MINUTES_TIMEOUT              600 //Longer timeout for volume top
 #define DEFAULT_CLI_LOG_FILE_DIRECTORY     DATADIR "/log/glusterfs"
-#define DEFAULT_LOG_FILE_DIRECTORY         DATADIR "/log/glusterfs"
 #define CLI_VOL_STATUS_BRICK_LEN              55
 #define CLI_TAB_LENGTH                         8
 #define CLI_BRICK_STATUS_LINE_LEN             78
 
-#define CLI_LOCAL_INIT(local, words, frame, dictionary) \
-        do {                                                 \
-                local = cli_local_get ();                    \
-                                                             \
-                if (local) {                                 \
-                        local->words = words;                \
-                        if (dictionary)                      \
-                                local->dict = dictionary;    \
-                        if (frame)                           \
-                                frame->local = local;        \
-                }                                            \
-        } while (0)
-
 enum argp_option_keys {
 	ARGP_DEBUG_KEY = 133,
 	ARGP_PORT_KEY = 'p',
@@ -65,6 +52,7 @@ struct cli_cmd;
 
 extern char *cli_vol_type_str[];
 extern char *cli_vol_status_str[];
+extern char *cli_vol_task_status_str[];
 
 typedef int (cli_cmd_cbk_t)(struct cli_state *state,
                             struct cli_cmd_word *word,
@@ -127,6 +115,8 @@ struct cli_state {
 
         char                 *log_file;
         gf_loglevel_t         log_level;
+
+        char                 *glusterd_sock;
 };
 
 struct cli_local {
@@ -141,11 +131,23 @@ struct cli_local {
         gf_boolean_t    all;
 #if (HAVE_LIB_XML)
         xmlTextWriterPtr        writer;
-        xmlBufferPtr            buf;
+        xmlDocPtr               doc;
         int                     vol_count;
 #endif
 };
 
+struct gf_cli_gsync_detailed_status_ {
+        char *node;
+        char *master;
+        char *slave;
+        char *health;
+        char *uptime;
+        char *files_syncd;
+        char *files_pending;
+        char *bytes_pending;
+        char *deletes_pending;
+};
+
 struct cli_volume_status {
         int            port;
         int            online;
@@ -164,6 +166,13 @@ struct cli_volume_status {
 #endif
 };
 
+struct snap_config_opt_vals_ {
+        char           *op_name;
+        char           *question;
+};
+
+typedef struct gf_cli_gsync_detailed_status_ gf_cli_gsync_status_t;
+
 typedef struct cli_volume_status cli_volume_status_t;
 
 typedef struct cli_local cli_local_t;
@@ -228,7 +237,7 @@ cli_cmd_quota_parse (const char **words, int wordcount, dict_t **opt);
 
 int32_t
 cli_cmd_volume_set_parse (const char **words, int wordcount,
-                          dict_t **options);
+                          dict_t **options, char **op_errstr);
 
 int32_t
 cli_cmd_volume_add_brick_parse (const char **words, int wordcount,
@@ -378,4 +387,14 @@ cli_xml_output_generic_volume (char *op, dict_t *dict, int op_ret, int op_errno,
 int
 cli_xml_output_vol_gsync (dict_t *dict, int op_ret, int op_errno,
                           char *op_errstr);
+int
+cli_xml_output_vol_status_tasks_detail (cli_local_t *local, dict_t *dict);
+
+char *
+is_server_debug_xlator (void *myframe);
+
+int32_t
+cli_cmd_snapshot_parse (const char **words, int wordcount, dict_t **options,
+                        struct cli_state *state);
+
 #endif /* __CLI_H__ */
diff --git a/configure.ac b/configure.ac
index 9640c9d50..b3d1ed184 100644
--- a/configure.ac
+++ b/configure.ac
@@ -24,13 +24,15 @@ if libtool --help 2>&1 | grep -q quiet; then
    AM_LIBTOOLFLAGS="--quiet";
 fi
 
-AM_CONFIG_HEADER([config.h])
+AC_CONFIG_HEADERS([config.h])
 
 AC_CONFIG_FILES([Makefile
-		libglusterfs/Makefile
-		libglusterfs/src/Makefile
-		glusterfsd/Makefile
-		glusterfsd/src/Makefile
+                libglusterfs/Makefile
+                libglusterfs/src/Makefile
+                geo-replication/src/peer_gsec_create
+                geo-replication/src/peer_add_secret_pub
+                glusterfsd/Makefile
+                glusterfsd/src/Makefile
                 rpc/Makefile
                 rpc/rpc-lib/Makefile
                 rpc/rpc-lib/src/Makefile
@@ -41,107 +43,137 @@ AC_CONFIG_FILES([Makefile
                 rpc/rpc-transport/rdma/src/Makefile
                 rpc/xdr/Makefile
                 rpc/xdr/src/Makefile
-		xlators/Makefile
-		xlators/mount/Makefile
-		xlators/mount/fuse/Makefile
-		xlators/mount/fuse/src/Makefile
-		xlators/mount/fuse/utils/mount.glusterfs
-		xlators/mount/fuse/utils/mount_glusterfs
-		xlators/mount/fuse/utils/Makefile
-		xlators/storage/Makefile
-		xlators/storage/posix/Makefile
-		xlators/storage/posix/src/Makefile
-		xlators/storage/bd_map/Makefile
-		xlators/storage/bd_map/src/Makefile
-		xlators/cluster/Makefile
-		xlators/cluster/afr/Makefile
-		xlators/cluster/afr/src/Makefile
-		xlators/cluster/stripe/Makefile
-		xlators/cluster/stripe/src/Makefile
-		xlators/cluster/dht/Makefile
-		xlators/cluster/dht/src/Makefile
-		xlators/performance/Makefile
-		xlators/performance/write-behind/Makefile
-		xlators/performance/write-behind/src/Makefile
-		xlators/performance/read-ahead/Makefile
-		xlators/performance/read-ahead/src/Makefile
-		xlators/performance/io-threads/Makefile
-		xlators/performance/io-threads/src/Makefile
-		xlators/performance/io-cache/Makefile
-		xlators/performance/io-cache/src/Makefile
-		xlators/performance/symlink-cache/Makefile
-		xlators/performance/symlink-cache/src/Makefile
-		xlators/performance/quick-read/Makefile
-		xlators/performance/quick-read/src/Makefile
+                xlators/Makefile
+                xlators/mount/Makefile
+                xlators/mount/fuse/Makefile
+                xlators/mount/fuse/src/Makefile
+                xlators/mount/fuse/utils/mount.glusterfs
+                xlators/mount/fuse/utils/mount_glusterfs
+                xlators/mount/fuse/utils/Makefile
+                xlators/storage/Makefile
+                xlators/storage/posix/Makefile
+                xlators/storage/posix/src/Makefile
+                xlators/storage/bd/Makefile
+                xlators/storage/bd/src/Makefile
+                xlators/cluster/Makefile
+                xlators/cluster/afr/Makefile
+                xlators/cluster/afr/src/Makefile
+                xlators/cluster/stripe/Makefile
+                xlators/cluster/stripe/src/Makefile
+                xlators/cluster/dht/Makefile
+                xlators/cluster/dht/src/Makefile
+                xlators/performance/Makefile
+                xlators/performance/write-behind/Makefile
+                xlators/performance/write-behind/src/Makefile
+                xlators/performance/read-ahead/Makefile
+                xlators/performance/read-ahead/src/Makefile
+                xlators/performance/readdir-ahead/Makefile
+                xlators/performance/readdir-ahead/src/Makefile
+                xlators/performance/io-threads/Makefile
+                xlators/performance/io-threads/src/Makefile
+                xlators/performance/io-cache/Makefile
+                xlators/performance/io-cache/src/Makefile
+                xlators/performance/symlink-cache/Makefile
+                xlators/performance/symlink-cache/src/Makefile
+                xlators/performance/quick-read/Makefile
+                xlators/performance/quick-read/src/Makefile
+                xlators/performance/open-behind/Makefile
+                xlators/performance/open-behind/src/Makefile
                 xlators/performance/md-cache/Makefile
                 xlators/performance/md-cache/src/Makefile
-		xlators/debug/Makefile
-		xlators/debug/trace/Makefile
-		xlators/debug/trace/src/Makefile
-		xlators/debug/error-gen/Makefile
-		xlators/debug/error-gen/src/Makefile
-		xlators/debug/io-stats/Makefile
-		xlators/debug/io-stats/src/Makefile
-		xlators/protocol/Makefile
-		xlators/protocol/auth/Makefile
-		xlators/protocol/auth/addr/Makefile
-		xlators/protocol/auth/addr/src/Makefile
-		xlators/protocol/auth/login/Makefile
-		xlators/protocol/auth/login/src/Makefile
-		xlators/protocol/client/Makefile
-		xlators/protocol/client/src/Makefile
-		xlators/protocol/server/Makefile
-		xlators/protocol/server/src/Makefile
-		xlators/features/Makefile
-		xlators/features/locks/Makefile
-		xlators/features/locks/src/Makefile
-		xlators/features/quota/Makefile
-		xlators/features/quota/src/Makefile
+                xlators/debug/Makefile
+                xlators/debug/trace/Makefile
+                xlators/debug/trace/src/Makefile
+                xlators/debug/error-gen/Makefile
+                xlators/debug/error-gen/src/Makefile
+                xlators/debug/io-stats/Makefile
+                xlators/debug/io-stats/src/Makefile
+                xlators/protocol/Makefile
+                xlators/protocol/auth/Makefile
+                xlators/protocol/auth/addr/Makefile
+                xlators/protocol/auth/addr/src/Makefile
+                xlators/protocol/auth/login/Makefile
+                xlators/protocol/auth/login/src/Makefile
+                xlators/protocol/client/Makefile
+                xlators/protocol/client/src/Makefile
+                xlators/protocol/server/Makefile
+                xlators/protocol/server/src/Makefile
+                xlators/features/Makefile
+		xlators/features/changelog/Makefile
+		xlators/features/changelog/src/Makefile
+		xlators/features/changelog/lib/Makefile
+		xlators/features/changelog/lib/src/Makefile
+                xlators/features/glupy/Makefile
+                xlators/features/glupy/src/Makefile
+                xlators/features/locks/Makefile
+                xlators/features/locks/src/Makefile
+                xlators/features/quota/Makefile
+                xlators/features/quota/src/Makefile
                 xlators/features/marker/Makefile
                 xlators/features/marker/src/Makefile
-                xlators/features/marker/utils/Makefile
-                xlators/features/marker/utils/src/Makefile
-                xlators/features/marker/utils/syncdaemon/Makefile
-		xlators/features/read-only/Makefile
-		xlators/features/read-only/src/Makefile
-		xlators/features/mac-compat/Makefile
-		xlators/features/mac-compat/src/Makefile
-		xlators/features/quiesce/Makefile
-		xlators/features/quiesce/src/Makefile
+                xlators/features/read-only/Makefile
+                xlators/features/read-only/src/Makefile
+                xlators/features/compress/Makefile
+                xlators/features/compress/src/Makefile
+                xlators/features/mac-compat/Makefile
+                xlators/features/mac-compat/src/Makefile
+                xlators/features/quiesce/Makefile
+                xlators/features/quiesce/src/Makefile
                 xlators/features/index/Makefile
                 xlators/features/index/src/Makefile
-		xlators/encryption/Makefile
-		xlators/encryption/rot-13/Makefile
-		xlators/encryption/rot-13/src/Makefile
+                xlators/features/protect/Makefile
+                xlators/features/protect/src/Makefile
+                xlators/features/gfid-access/Makefile
+                xlators/features/gfid-access/src/Makefile
+                xlators/playground/Makefile
+                xlators/playground/template/Makefile
+                xlators/playground/template/src/Makefile
+                xlators/encryption/Makefile
+                xlators/encryption/rot-13/Makefile
+                xlators/encryption/rot-13/src/Makefile
+                xlators/encryption/crypt/Makefile
+                xlators/encryption/crypt/src/Makefile
+		xlators/features/qemu-block/Makefile
+		xlators/features/qemu-block/src/Makefile
                 xlators/system/Makefile
                 xlators/system/posix-acl/Makefile
                 xlators/system/posix-acl/src/Makefile
-                cli/Makefile
-                cli/src/Makefile
-		doc/Makefile
-		extras/Makefile
-		extras/init.d/Makefile
-		extras/init.d/glusterd.plist
-                extras/init.d/glusterd-Debian
-                extras/init.d/glusterd-Redhat
-                extras/init.d/glusterd-SuSE
-		extras/benchmarking/Makefile
-                extras/hook-scripts/Makefile
-		extras/ocf/Makefile
-		extras/ocf/glusterd
-		extras/ocf/volume
-		contrib/fuse-util/Makefile
-		contrib/uuid/uuid_types.h
                 xlators/nfs/Makefile
                 xlators/nfs/server/Makefile
                 xlators/nfs/server/src/Makefile
                 xlators/mgmt/Makefile
                 xlators/mgmt/glusterd/Makefile
                 xlators/mgmt/glusterd/src/Makefile
-		glusterfs-api.pc
-		api/Makefile
-		api/src/Makefile
-		glusterfs.spec])
+                cli/Makefile
+                cli/src/Makefile
+                doc/Makefile
+                extras/Makefile
+                extras/init.d/Makefile
+                extras/init.d/glusterd.plist
+                extras/init.d/glusterd-Debian
+                extras/init.d/glusterd-Redhat
+                extras/init.d/glusterd-SuSE
+                extras/systemd/Makefile
+                extras/systemd/glusterd.service
+                extras/benchmarking/Makefile
+                extras/hook-scripts/Makefile
+                extras/ocf/Makefile
+                extras/ocf/glusterd
+                extras/ocf/volume
+                extras/LinuxRPM/Makefile
+                extras/geo-rep/Makefile
+                contrib/fuse-util/Makefile
+                contrib/uuid/uuid_types.h
+                glusterfs-api.pc
+                libgfchangelog.pc
+                api/Makefile
+                api/src/Makefile
+                api/examples/Makefile
+                api/examples/setup.py
+		geo-replication/Makefile
+		geo-replication/src/Makefile
+		geo-replication/syncdaemon/Makefile
+                glusterfs.spec])
 
 AC_CANONICAL_HOST
 
@@ -161,6 +193,12 @@ AC_ARG_WITH(mountutildir,
             [mountutildir='/sbin'])
 AC_SUBST(mountutildir)
 
+AC_ARG_WITH(systemddir,
+            [  --with-systemddir=DIR systemd service files in DIR @<:@/usr/lib/systemd/system@:>@],
+            [systemddir=$withval],
+            [systemddir='/usr/lib/systemd/system'])
+AC_SUBST(systemddir)
+
 AC_ARG_WITH(initdir,
             [  --with-initdir=DIR init.d scripts in DIR @<:@/etc/init.d@:>@],
             [initdir=$withval],
@@ -174,10 +212,11 @@ AC_ARG_WITH(launchddir,
 AC_SUBST(launchddir)
 
 AC_ARG_WITH([ocf],
-            [AS_HELP_STRING([--with-ocf], [build OCF-compliant cluster resource agents])],
+            [AS_HELP_STRING([--without-ocf], [build OCF-compliant cluster resource agents])],
             ,
-            [with_ocf=no])
-AM_CONDITIONAL(WITH_OCF, [ test "$with_ocf" = "yes" ])
+            [OCF_SUBDIR='ocf'],
+            )
+AC_SUBST(OCF_SUBDIR)
 
 # LEX needs a check
 AC_PROG_LEX
@@ -222,6 +261,8 @@ AC_CHECK_HEADERS([sys/extattr.h])
 
 AC_CHECK_HEADERS([openssl/md5.h])
 
+AC_CHECK_HEADERS([linux/falloc.h])
+
 case $host_os in
   darwin*)
     if ! test "`/usr/bin/sw_vers | grep ProductVersion: | cut -f 2 | cut -d. -f2`" -ge 5; then
@@ -255,8 +296,8 @@ fi
 
 # FUSE section
 AC_ARG_ENABLE([fuse-client],
-	      AC_HELP_STRING([--disable-fuse-client],
-			     [Do not build the fuse client. NOTE: you cannot mount glusterfs without the client]))
+              AC_HELP_STRING([--disable-fuse-client],
+                             [Do not build the fuse client. NOTE: you cannot mount glusterfs without the client]))
 
 BUILD_FUSE_CLIENT=no
 if test "x$enable_fuse_client" != "xno"; then
@@ -265,14 +306,22 @@ if test "x$enable_fuse_client" != "xno"; then
 fi
 
 AC_ARG_ENABLE([bd-xlator],
-                AC_HELP_STRING([--enable-bd-xlator],
-                        [Build BD xlator]))
+              AC_HELP_STRING([--enable-bd-xlator], [Build BD xlator]))
 
 if test "x$enable_bd_xlator" != "xno"; then
   AC_CHECK_LIB([lvm2app],
-                  [lvm_init],
-                  [HAVE_BD_LIB="yes"],
-                  [HAVE_BD_LIB="no"])
+               [lvm_init,lvm_lv_from_name],
+               [HAVE_BD_LIB="yes"],
+               [HAVE_BD_LIB="no"])
+
+if test "x$HAVE_BD_LIB" = "xyes"; then
+    # lvm_lv_from_name() has been made public with lvm2-2.02.79
+    AC_CHECK_DECLS(
+                  [lvm_lv_from_name],
+                  [NEED_LVM_LV_FROM_NAME_DECL="no"],
+                  [NEED_LVM_LV_FROM_NAME_DECL="yes"],
+                  [[#include <lvm2app.h>]])
+  fi
 fi
 
 if test "x$enable_bd_xlator" = "xyes" -a "x$HAVE_BD_LIB" = "xno"; then
@@ -281,68 +330,128 @@ if test "x$enable_bd_xlator" = "xyes" -a "x$HAVE_BD_LIB" = "xno"; then
 fi
 
 BUILD_BD_XLATOR=no
-if test "x${enable_bd_xlator}" != "xno" -a "x${HAVE_BD_LIB}" = "xyes"; then
+if test "x${enable-bd-xlator}" != "xno" -a "x${HAVE_BD_LIB}" = "xyes"; then
   BUILD_BD_XLATOR=yes
-  AC_DEFINE(HAVE_BD_XLATOR, 1, [define if lvm2app library found and bd
-                  xlator enabled])
+  AC_DEFINE(HAVE_BD_XLATOR, 1, [define if lvm2app library found and bd xlator
+                            enabled])
+  if test "x$NEED_LVM_LV_FROM_NAME_DECL" = "xyes"; then
+    AC_DEFINE(NEED_LVM_LV_FROM_NAME_DECL, 1, [defined if lvm_lv_from_name()
+                  was not found in the lvm2app.h header, but can be linked])
+  fi
 fi
 
 AM_CONDITIONAL([ENABLE_BD_XLATOR], [test x$BUILD_BD_XLATOR = xyes])
 
+# start encryption/crypt section
+
+AC_CHECK_HEADERS([openssl/cmac.h], [have_cmac_h=yes], [have_cmac_h=no])
+
+AC_ARG_ENABLE([crypt-xlator],
+	AC_HELP_STRING([--enable-crypt-xlator], [Build crypt encryption xlator]))
+
+if test "x$enable_crypt_xlator" = "xyes" -a "x$have_cmac_h" = "xno"; then
+   echo "Encryption xlator requires OpenSSL with cmac.h"
+   exit 1
+fi
+
+BUILD_CRYPT_XLATOR=no
+if test "x$enable_crypt_xlator" != "xno" -a "x$have_cmac_h" = "xyes"; then
+   BUILD_CRYPT_XLATOR=yes
+   AC_DEFINE(HAVE_CRYPT_XLATOR, 1, [enable building crypt encryption xlator])
+fi
+
+AM_CONDITIONAL([ENABLE_CRYPT_XLATOR], [test x$BUILD_CRYPT_XLATOR = xyes])
+
 AC_SUBST(FUSE_CLIENT_SUBDIR)
 # end FUSE section
 
 
 # FUSERMOUNT section
 AC_ARG_ENABLE([fusermount],
-              AC_HELP_STRING([--enable-fusermount],
-                             [Build fusermount]))
+              AC_HELP_STRING([--disable-fusermount],
+                             [Use system's fusermount]))
 
-BUILD_FUSERMOUNT="no"
-if test "x$enable_fusermount" = "xyes"; then
-  FUSERMOUNT_SUBDIR="contrib/fuse-util"
-  BUILD_FUSERMOUNT="yes"
+BUILD_FUSERMOUNT="yes"
+if test "x$enable_fusermount" = "xno"; then
+  BUILD_FUSERMOUNT="no"
+else
   AC_DEFINE(GF_FUSERMOUNT, 1, [Use our own fusermount])
+  FUSERMOUNT_SUBDIR="contrib/fuse-util"
 fi
 
 AC_SUBST(FUSERMOUNT_SUBDIR)
 #end FUSERMOUNT section
 
+# QEMU_BLOCK section
+
+AC_ARG_ENABLE([qemu-block],
+                AC_HELP_STRING([--enable-qemu-block],
+                        [Build QEMU Block formats translator]))
+
+if test "x$enable_qemu_block" != "xno"; then
+  PKG_CHECK_MODULES([GLIB], [glib-2.0],
+                    [HAVE_GLIB_2="yes"],
+  		    [HAVE_GLIB_2="no"])
+fi
+
+if test "x$enable_qemu_block" = "xyes" -a "x$HAVE_GLIB_2" = "xno"; then
+   echo "QEMU Block formats translator requires libglib-2.0, but missing."
+   exit 1
+fi
+
+BUILD_QEMU_BLOCK=no
+if test "x${enable_qemu_block}" != "xno" -a "x${HAVE_GLIB_2}" = "xyes"; then
+  BUILD_QEMU_BLOCK=yes
+  AC_DEFINE(HAVE_QEMU_BLOCK, 1, [define if libglib-2.0 library found and QEMU
+                  	     Block translator enabled])
+fi
+
+AM_CONDITIONAL([ENABLE_QEMU_BLOCK], [test x$BUILD_QEMU_BLOCK = xyes])
+
+# end QEMU_BLOCK section
 
 # EPOLL section
 AC_ARG_ENABLE([epoll],
-	      AC_HELP_STRING([--disable-epoll],
-			     [Use poll instead of epoll.]))
+              AC_HELP_STRING([--disable-epoll],
+                             [Use poll instead of epoll.]))
 
 BUILD_EPOLL=no
 if test "x$enable_epoll" != "xno"; then
    AC_CHECK_HEADERS([sys/epoll.h],
                     [BUILD_EPOLL=yes],
-		    [BUILD_EPOLL=no])
+                    [BUILD_EPOLL=no])
 fi
 # end EPOLL section
 
 
 # IBVERBS section
 AC_ARG_ENABLE([ibverbs],
-	      AC_HELP_STRING([--disable-ibverbs],
-			     [Do not build the ibverbs transport]))
+              AC_HELP_STRING([--disable-ibverbs],
+                             [Do not build the ibverbs transport]))
 
 if test "x$enable_ibverbs" != "xno"; then
   AC_CHECK_LIB([ibverbs],
                [ibv_get_device_list],
-	       [HAVE_LIBIBVERBS="yes"],
-	       [HAVE_LIBIBVERBS="no"])
+               [HAVE_LIBIBVERBS="yes"],
+               [HAVE_LIBIBVERBS="no"])
+  AC_CHECK_LIB([rdmacm], [rdma_create_id], [HAVE_RDMACM="yes"], [HAVE_RDMACM="no"])
 fi
 
-if test "x$enable_ibverbs" = "xyes" -a "x$HAVE_LIBIBVERBS" = "xno"; then
-   echo "ibverbs requested but not found."
-   exit 1
+if test "x$enable_ibverbs" = "xyes"; then
+   if test "x$HAVE_LIBIBVERBS" = "xno"; then
+      echo "ibverbs-transport requested, but libibverbs is not present."
+      exit 1
+   fi
+
+   if test "x$HAVE_RDMACM" = "xno"; then
+      echo "ibverbs-transport requested, but librdmacm is not present."
+      exit 1
+   fi
 fi
 
 BUILD_RDMA=no
 BUILD_IBVERBS=no
-if test "x$enable_ibverbs" != "xno" -a "x$HAVE_LIBIBVERBS" = "xyes"; then
+if test "x$enable_ibverbs" != "xno" -a "x$HAVE_LIBIBVERBS" = "xyes" -a "x$HAVE_RDMACM" = "xyes"; then
   IBVERBS_SUBDIR=ib-verbs
   BUILD_IBVERBS=yes
   RDMA_SUBDIR=rdma
@@ -356,8 +465,8 @@ AC_SUBST(RDMA_SUBDIR)
 
 # SYNCDAEMON section
 AC_ARG_ENABLE([georeplication],
-	      AC_HELP_STRING([--disable-georeplication],
-			     [Do not install georeplication components]))
+              AC_HELP_STRING([--disable-georeplication],
+                             [Do not install georeplication components]))
 
 BUILD_SYNCDAEMON=no
 case $host_os in
@@ -369,12 +478,12 @@ case $host_os in
        ;;
      *)
 #disabling geo replication for non-linux platforms
-	enable_georeplication=no
+        enable_georeplication=no
         ;;
 esac
 SYNCDAEMON_COMPILE=0
 if test "x$enable_georeplication" != "xno"; then
-  SYNCDAEMON_SUBDIR=utils
+  SYNCDAEMON_SUBDIR=geo-replication
   SYNCDAEMON_COMPILE=1
 
   BUILD_SYNCDAEMON="yes"
@@ -398,6 +507,17 @@ AC_SUBST(SYNCDAEMON_COMPILE)
 AC_SUBST(SYNCDAEMON_SUBDIR)
 # end SYNCDAEMON section
 
+# CDC xlator - check if libz is present if so enable HAVE_LIB_Z
+echo -n "checking if libz is present... "
+
+PKG_CHECK_MODULES([ZLIB], [zlib >= 1.2.0],
+                  [echo "yes (features requiring zlib enabled)"  AC_DEFINE(HAVE_LIB_Z, 1, [define if zlib is present])],
+                  [echo "no"] )
+
+AC_SUBST(LIBZ_CFLAGS)
+AC_SUBST(LIBZ_LIBS)
+# end CDC xlator secion
+
 # check for systemtap/dtrace
 BUILD_SYSTEMTAP=no
 AC_MSG_CHECKING([whether to include systemtap tracing support])
@@ -430,15 +550,24 @@ if test "x${DTRACE}" = "xyes" -a "x${SDT_H_FOUND}" = "xyes"; then
 fi
 # end of systemtap/dtrace
 
-#check if libxml is present if so enable HAVE_LIB_XML
-echo -n "checking if libxml2 is present... "
-
-PKG_CHECK_MODULES([LIBXML2], [libxml-2.0 >= 2.6.19],
-                  [echo "yes (features requiring libxml2 enabled)"  AC_DEFINE(HAVE_LIB_XML, 1, [define if libxml2 is present])],
-                  [echo "no"] )
-
-AC_SUBST(LIBXML2_CFLAGS)
-AC_SUBST(LIBXML2_LIBS)
+# xml-output
+AC_ARG_ENABLE([xml-output],
+              AC_HELP_STRING([--disable-xml-output],
+                             [Disable the xml output]))
+BUILD_XML_OUTPUT="yes"
+if test "x$enable_xml_output" != "xno"; then
+    #check if libxml is present if so enable HAVE_LIB_XML
+    m4_ifdef([AM_PATH_XML2],[AM_PATH_XML2([2.6.19])], [no_xml=yes])
+    if test "x${no_xml}" = "x"; then
+        AC_DEFINE([HAVE_LIB_XML], [1], [Define to 1 if using libxml2.])
+    else
+        AC_MSG_WARN([libxml2 devel libraries not found disabling XML support])
+        BUILD_XML_OUTPUT="no"
+    fi
+else
+    BUILD_XML_OUTPUT="no"
+fi
+# end of xml-output
 
 dnl FreeBSD > 5 has execinfo as a Ported library for giving a workaround
 dnl solution to GCC backtrace functionality
@@ -464,9 +593,9 @@ AC_CHECK_MEMBERS([struct stat.st_atim.tv_nsec])
 dnl FreeBSD, NetBSD
 AC_CHECK_MEMBERS([struct stat.st_atimespec.tv_nsec])
 case $host_os in
-	*netbsd*)
-	CFLAGS=-D_INCOMPLETE_XOPEN_C063
-	;;
+        *netbsd*)
+        CFLAGS+=" -D_INCOMPLETE_XOPEN_C063"
+        ;;
 esac
 AC_CHECK_FUNC([linkat], [have_linkat=yes])
 if test "x${have_linkat}" = "xyes"; then
@@ -474,11 +603,15 @@ if test "x${have_linkat}" = "xyes"; then
 fi
 AC_SUBST(HAVE_LINKAT)
 
+dnl check for Monotonic clock
+AC_CHECK_FUNC([clock_gettime], [has_monotonic_clock=yes], AC_CHECK_LIB([rt], [clock_gettime], , AC_MSG_WARN([System doesn't have monotonic clock using contrib])))
+
 dnl Check for argp
 AC_CHECK_HEADER([argp.h], AC_DEFINE(HAVE_ARGP, 1, [have argp]))
 AC_CONFIG_SUBDIRS(argp-standalone)
+
 BUILD_ARGP_STANDALONE=no
-if test "x${ac_cv_header_argp_h}" = "xno"; then 
+if test "x${ac_cv_header_argp_h}" = "xno"; then
    BUILD_ARGP_STANDALONE=yes
    ARGP_STANDALONE_CPPFLAGS='-I${top_srcdir}/argp-standalone'
    ARGP_STANDALONE_LDADD='${top_builddir}/argp-standalone/libargp.a'
@@ -499,7 +632,18 @@ if test "x${have_fdatasync}" = "xyes"; then
    AC_DEFINE(HAVE_FDATASYNC, 1, [define if fdatasync exists])
 fi
 
-# Check the distribution where you are compiling glusterfs on 
+AC_CHECK_FUNC([fallocate], [have_fallocate=yes])
+if test "x${have_fallocate}" = "xyes"; then
+   AC_DEFINE(HAVE_FALLOCATE, 1, [define if fallocate exists])
+fi
+
+AC_CHECK_FUNC([posix_fallocate], [have_posix_fallocate=yes])
+if test "x${have_posix_fallocate}" = "xyes"; then
+   AC_DEFINE(HAVE_POSIX_FALLOCATE, 1, [define if posix_fallocate exists])
+fi
+
+
+# Check the distribution where you are compiling glusterfs on
 
 GF_DISTRIBUTION=
 AC_CHECK_FILE([/etc/debian_version])
@@ -520,63 +664,85 @@ AC_SUBST(GF_DISTRIBUTION)
 
 GF_HOST_OS=""
 GF_LDFLAGS="-rdynamic"
-CFLAGS="-g"
+
+# check for gcc -Werror=format-security
+saved_CFLAGS=$CFLAGS
+CFLAGS="-Wformat -Werror=format-security"
+AC_MSG_CHECKING([whether $CC accepts -Werror=format-security])
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [cc_werror_format_security=yes], [cc_werror_format_security=no])
+echo $cc_werror_format_security
+if test "x$cc_werror_format_security" = "xno"; then
+    CFLAGS="$saved_CFLAGS"
+else
+    CFLAGS="$saved_CFLAGS $CFLAGS"
+fi
+
+# check for gcc -Werror=implicit-function-declaration
+saved_CFLAGS=$CFLAGS
+CFLAGS="-Werror=implicit-function-declaration"
+AC_MSG_CHECKING([whether $CC accepts -Werror=implicit-function-declaration])
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM()], [cc_werror_implicit=yes], [cc_werror_implicit=no])
+echo $cc_werror_implicit
+if test "x$cc_werror_implicit" = "xno"; then
+    CFLAGS="$saved_CFLAGS"
+else
+    CFLAGS="$saved_CFLAGS $CFLAGS"
+fi
 
 case $host_os in
      linux*)
-     dnl	GF_LINUX_HOST_OS=1
         GF_HOST_OS="GF_LINUX_HOST_OS"
-	GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -O0"
-	GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
-	GF_LDADD="${ARGP_STANDALONE_LDADD}"
-	GF_FUSE_CFLAGS="-DFUSERMOUNT_DIR=\\\"\$(bindir)\\\""
-	;;
+        GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -O0"
+        GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
+        GF_LDADD="${ARGP_STANDALONE_LDADD}"
+        GF_FUSE_CFLAGS="-DFUSERMOUNT_DIR=\\\"\$(bindir)\\\""
+        ;;
      solaris*)
         GF_HOST_OS="GF_SOLARIS_HOST_OS"
-	GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -O0 -m64"
-	GF_LDFLAGS=""
-	GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
-	GF_LDADD="${ARGP_STANDALONE_LDADD}"
-	GF_GLUSTERFS_LIBS="-lnsl -lresolv -lsocket"
+        GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS -O0 -m64"
+        GF_LDFLAGS=""
+        GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
+        GF_LDADD="${ARGP_STANDALONE_LDADD}"
+        GF_GLUSTERFS_LIBS="-lnsl -lresolv -lsocket"
         BUILD_FUSE_CLIENT=no
         FUSE_CLIENT_SUBDIR=""
-	;;
+        ;;
      *netbsd*)
-	GF_HOST_OS="GF_BSD_HOST_OS"
-	GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D_INCOMPLETE_XOPEN_C063"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
-	GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
-	GF_LDADD="${ARGP_STANDALONE_LDADD}"
-	if test "x$ac_cv_header_execinfo_h" = "xyes"; then
-	   GF_GLUSTERFS_LIBS="-lexecinfo"
-	fi
-	GF_FUSE_LDADD="-lperfuse"
-	BUILD_FUSE_CLIENT=yes
-	LEXLIB=""
-	;;
+        GF_HOST_OS="GF_BSD_HOST_OS"
+        GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D_INCOMPLETE_XOPEN_C063"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
+        GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
+        GF_LDADD="${ARGP_STANDALONE_LDADD}"
+        if test "x$ac_cv_header_execinfo_h" = "xyes"; then
+           GF_GLUSTERFS_LIBS="-lexecinfo"
+        fi
+        GF_FUSE_LDADD="-lperfuse"
+        BUILD_FUSE_CLIENT=yes
+        LEXLIB=""
+        ;;
      *bsd*)
         GF_HOST_OS="GF_BSD_HOST_OS"
-	GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -O0"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
-	GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
-	GF_LDADD="${ARGP_STANDALONE_LDADD}"
-	if test "x$ac_cv_header_execinfo_h" = "xyes"; then
-	   GF_GLUSTERFS_LIBS="-lexecinfo"
-	fi
-	BUILD_FUSE_CLIENT=no
-	;;
+        GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -O0"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
+        GF_GLUSTERFS_CFLAGS="${GF_CFLAGS}"
+        GF_LDADD="${ARGP_STANDALONE_LDADD}"
+        if test "x$ac_cv_header_execinfo_h" = "xyes"; then
+           GF_GLUSTERFS_LIBS="-lexecinfo"
+        fi
+        BUILD_FUSE_CLIENT=no
+        ;;
      darwin*)
         GF_HOST_OS="GF_DARWIN_HOST_OS"
-	LIBTOOL=glibtool
-	GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D__DARWIN_64_BIT_INO_T -bundle -undefined suppress -flat_namespace -D_XOPEN_SOURCE -O0"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
-	GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
-	GF_GLUSTERFS_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D__DARWIN_64_BIT_INO_T -undefined suppress -flat_namespace -O0"
-	GF_LDADD="${ARGP_STANDALONE_LDADD}"
-	GF_FUSE_CFLAGS="-I\$(CONTRIBDIR)/macfuse"
-	;;
+        LIBTOOL=glibtool
+        GF_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D__DARWIN_64_BIT_INO_T -bundle -undefined suppress -flat_namespace -D_XOPEN_SOURCE -O0"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_BASENAME"
+        GF_CFLAGS="${GF_CFLAGS} -DTHREAD_UNSAFE_DIRNAME"
+        GF_GLUSTERFS_CFLAGS="${ARGP_STANDALONE_CPPFLAGS} -D__DARWIN_64_BIT_INO_T -undefined suppress -flat_namespace -O0"
+        GF_LDADD="${ARGP_STANDALONE_LDADD}"
+        GF_FUSE_CFLAGS="-I\$(CONTRIBDIR)/macfuse"
+        ;;
 esac
 
 # enable debug section
@@ -584,17 +750,30 @@ AC_ARG_ENABLE([debug],
               AC_HELP_STRING([--enable-debug],
                              [Enable debug build options.]))
 
-DEBUG=no
+BUILD_DEBUG=no
 if test "x$enable_debug" = "xyes"; then
-   DEBUG=yes
-   CFLAGS="-O0 $CFLAGS"
+   BUILD_DEBUG=yes
+   CFLAGS=`echo $CFLAGS | sed -e s/O2/O0/`
 else
-   CFLAGS="-O2 $CFLAGS"
-   DEBUG=no
+   BUILD_DEBUG=no
 fi
 AC_SUBST(CFLAGS)
 # end enable debug section
 
+# syslog section
+AC_ARG_ENABLE([syslog],
+	      AC_HELP_STRING([--disable-syslog],
+			     [Disable syslog for logging]))
+
+USE_SYSLOG="yes"
+if test "x$enable_syslog" != "xno"; then
+  AC_DEFINE(GF_USE_SYSLOG, 1, [Use syslog for logging])
+else
+  USE_SYSLOG="no"
+fi
+AM_CONDITIONAL([ENABLE_SYSLOG], [test x$USE_SYSLOG = xyes])
+#end syslog section
+
 BUILD_READLINE=no
 AC_CHECK_LIB([readline -lcurses],[readline],[RLLIBS="-lreadline -lcurses"])
 AC_CHECK_LIB([readline -ltermcap],[readline],[RLLIBS="-lreadline -ltermcap"])
@@ -613,6 +792,55 @@ if test "x$LIBAIO" != "x"; then
    BUILD_LIBAIO=yes
 fi
 
+# glupy section
+BUILD_GLUPY=no
+have_python2=no
+have_Python_h=no
+
+AM_PATH_PYTHON()
+if echo $PYTHON_VERSION | grep ^2; then
+  have_python2=yes
+fi
+AC_CHECK_HEADERS([python$PYTHON_VERSION/Python.h],[have_Python_h=yes],[])
+AC_ARG_ENABLE([glupy],
+              AS_HELP_STRING([--enable-glupy],
+                             [build glupy]))
+case x$enable_glupy in
+   xyes)
+      if test "x$have_python2" = "xyes" -a "x$have_Python_h" = "xyes"; then
+         BUILD_GLUPY=yes
+      else
+         AC_MSG_ERROR([glupy requires python-devel/python-dev package and python2.x])
+      fi
+      ;;
+   xno)
+      ;;
+   *)
+      if test "x$have_python2" = "xyes" -a "x$have_Python_h" = "xyes"; then
+         BUILD_GLUPY=yes
+      else
+         AC_MSG_WARN([
+        ---------------------------------------------------------------------------------
+         cannot build glupy. python 2.x and python-devel/python-dev package are required.
+        ---------------------------------------------------------------------------------])
+      fi
+      ;;
+esac
+
+if test "x$BUILD_GLUPY" = "xyes"; then
+   BUILD_PYTHON_INC=`$PYTHON -c "from distutils import sysconfig; print sysconfig.get_python_inc()"`
+   BUILD_PYTHON_LIB=python$PYTHON_VERSION
+   GLUPY_SUBDIR=glupy
+   GLUPY_SUBDIR_MAKEFILE=xlators/features/glupy/Makefile
+   GLUPY_SUBDIR_SRC_MAKEFILE=xlators/features/glupy/src/Makefile
+   echo "building glupy with -isystem $BUILD_PYTHON_INC -l $BUILD_PYTHON_LIB"
+   AC_SUBST(BUILD_PYTHON_INC)
+   AC_SUBST(BUILD_PYTHON_LIB)
+   AC_SUBST(GLUPY_SUBDIR)
+   AC_SUBST(GLUPY_SUBDIR_MAKEFILE)
+   AC_SUBST(GLUPY_SUBDIR_SRC_MAKEFILE)
+fi
+# end glupy section
 
 AC_SUBST(GF_HOST_OS)
 AC_SUBST([GF_GLUSTERFS_LIBS])
@@ -652,7 +880,12 @@ echo "fusermount           : $BUILD_FUSERMOUNT"
 echo "readline             : $BUILD_READLINE"
 echo "georeplication       : $BUILD_SYNCDAEMON"
 echo "Linux-AIO            : $BUILD_LIBAIO"
-echo "Enable Debug         : $DEBUG"
+echo "Enable Debug         : $BUILD_DEBUG"
 echo "systemtap            : $BUILD_SYSTEMTAP"
-echo "Block Device backend : $BUILD_BD_XLATOR"
+echo "Block Device xlator  : $BUILD_BD_XLATOR"
+echo "glupy                : $BUILD_GLUPY"
+echo "Use syslog           : $USE_SYSLOG"
+echo "XML output           : $BUILD_XML_OUTPUT"
+echo "QEMU Block formats   : $BUILD_QEMU_BLOCK"
+echo "Encryption xlator    : $BUILD_CRYPT_XLATOR"
 echo
diff --git a/contrib/fuse-include/fuse_kernel.h b/contrib/fuse-include/fuse_kernel.h
index 9ae25d6f9..60bb2f9f7 100644
--- a/contrib/fuse-include/fuse_kernel.h
+++ b/contrib/fuse-include/fuse_kernel.h
@@ -60,23 +60,75 @@
  * 7.13
  *  - make max number of background requests and congestion threshold
  *    tunables
+ *
+ * 7.14
+ *  - add splice support to fuse device
+ *
+ * 7.15
+ *  - add store notify
+ *  - add retrieve notify
+ *
+ * 7.16
+ *  - add BATCH_FORGET request
+ *  - FUSE_IOCTL_UNRESTRICTED shall now return with array of 'struct
+ *    fuse_ioctl_iovec' instead of ambiguous 'struct iovec'
+ *  - add FUSE_IOCTL_32BIT flag
+ *
+ * 7.17
+ *  - add FUSE_FLOCK_LOCKS and FUSE_RELEASE_FLOCK_UNLOCK
+ *
+ * 7.18
+ *  - add FUSE_IOCTL_DIR flag
+ *  - add FUSE_NOTIFY_DELETE
+ *
+ * 7.19
+ *  - add FUSE_FALLOCATE
+ *
+ * 7.20
+ *  - add FUSE_AUTO_INVAL_DATA
+ *
+ * 7.21
+ *  - add FUSE_READDIRPLUS
+ *  - send the requested events in POLL request
+ *
+ * 7.22
+ *  - add FUSE_ASYNC_DIO
  */
 
 #ifndef _LINUX_FUSE_H
 #define _LINUX_FUSE_H
 
-#include <sys/types.h>
-#define __u64 uint64_t
-#define __s64 int64_t
-#define __u32 uint32_t
-#define __s32 int32_t
-#define __u16 uint16_t
+#ifdef __KERNEL__
+#include <linux/types.h>
+#else
+#include <stdint.h>
+#endif
+
+/*
+ * Version negotiation:
+ *
+ * Both the kernel and userspace send the version they support in the
+ * INIT request and reply respectively.
+ *
+ * If the major versions match then both shall use the smallest
+ * of the two minor versions for communication.
+ *
+ * If the kernel supports a larger major version, then userspace shall
+ * reply with the major version it supports, ignore the rest of the
+ * INIT message and expect a new INIT message from the kernel with a
+ * matching major version.
+ *
+ * If the library supports a larger major version, then it shall fall
+ * back to the major protocol version sent by the kernel for
+ * communication and reply with that major version (and an arbitrary
+ * supported minor version).
+ */
 
 /** Version number of this interface */
 #define FUSE_KERNEL_VERSION 7
 
 /** Minor version number of this interface */
-#define FUSE_KERNEL_MINOR_VERSION 13
+#define FUSE_KERNEL_MINOR_VERSION 22
 
 /** The node ID of the root inode */
 #define FUSE_ROOT_ID 1
@@ -85,42 +137,42 @@
    userspace works under 64bit kernels */
 
 struct fuse_attr {
-	__u64	ino;
-	__u64	size;
-	__u64	blocks;
-	__u64	atime;
-	__u64	mtime;
-	__u64	ctime;
-	__u32	atimensec;
-	__u32	mtimensec;
-	__u32	ctimensec;
-	__u32	mode;
-	__u32	nlink;
-	__u32	uid;
-	__u32	gid;
-	__u32	rdev;
-	__u32	blksize;
-	__u32	padding;
+	uint64_t	ino;
+	uint64_t	size;
+	uint64_t	blocks;
+	uint64_t	atime;
+	uint64_t	mtime;
+	uint64_t	ctime;
+	uint32_t	atimensec;
+	uint32_t	mtimensec;
+	uint32_t	ctimensec;
+	uint32_t	mode;
+	uint32_t	nlink;
+	uint32_t	uid;
+	uint32_t	gid;
+	uint32_t	rdev;
+	uint32_t	blksize;
+	uint32_t	padding;
 };
 
 struct fuse_kstatfs {
-	__u64	blocks;
-	__u64	bfree;
-	__u64	bavail;
-	__u64	files;
-	__u64	ffree;
-	__u32	bsize;
-	__u32	namelen;
-	__u32	frsize;
-	__u32	padding;
-	__u32	spare[6];
+	uint64_t	blocks;
+	uint64_t	bfree;
+	uint64_t	bavail;
+	uint64_t	files;
+	uint64_t	ffree;
+	uint32_t	bsize;
+	uint32_t	namelen;
+	uint32_t	frsize;
+	uint32_t	padding;
+	uint32_t	spare[6];
 };
 
 struct fuse_file_lock {
-	__u64	start;
-	__u64	end;
-	__u32	type;
-	__u32	pid; /* tgid */
+	uint64_t	start;
+	uint64_t	end;
+	uint32_t	type;
+	uint32_t	pid; /* tgid */
 };
 
 /**
@@ -151,8 +203,22 @@ struct fuse_file_lock {
 /**
  * INIT request/reply flags
  *
+ * FUSE_ASYNC_READ: asynchronous read requests
+ * FUSE_POSIX_LOCKS: remote locking for POSIX file locks
+ * FUSE_FILE_OPS: kernel sends file handle for fstat, etc... (not yet supported)
+ * FUSE_ATOMIC_O_TRUNC: handles the O_TRUNC open flag in the filesystem
  * FUSE_EXPORT_SUPPORT: filesystem handles lookups of "." and ".."
+ * FUSE_BIG_WRITES: filesystem can handle write size larger than 4kB
  * FUSE_DONT_MASK: don't apply umask to file mode on create operations
+ * FUSE_SPLICE_WRITE: kernel supports splice write on the device
+ * FUSE_SPLICE_MOVE: kernel supports splice move on the device
+ * FUSE_SPLICE_READ: kernel supports splice read on the device
+ * FUSE_FLOCK_LOCKS: remote locking for BSD style file locks
+ * FUSE_HAS_IOCTL_DIR: kernel supports ioctl on directories
+ * FUSE_AUTO_INVAL_DATA: automatically invalidate cached pages
+ * FUSE_DO_READDIRPLUS: do READDIRPLUS (READDIR+LOOKUP in one)
+ * FUSE_READDIRPLUS_AUTO: adaptive readdirplus
+ * FUSE_ASYNC_DIO: asynchronous direct I/O submission
  */
 #define FUSE_ASYNC_READ		(1 << 0)
 #define FUSE_POSIX_LOCKS	(1 << 1)
@@ -161,6 +227,15 @@ struct fuse_file_lock {
 #define FUSE_EXPORT_SUPPORT	(1 << 4)
 #define FUSE_BIG_WRITES		(1 << 5)
 #define FUSE_DONT_MASK		(1 << 6)
+#define FUSE_SPLICE_WRITE	(1 << 7)
+#define FUSE_SPLICE_MOVE	(1 << 8)
+#define FUSE_SPLICE_READ	(1 << 9)
+#define FUSE_FLOCK_LOCKS	(1 << 10)
+#define FUSE_HAS_IOCTL_DIR	(1 << 11)
+#define FUSE_AUTO_INVAL_DATA	(1 << 12)
+#define FUSE_DO_READDIRPLUS	(1 << 13)
+#define FUSE_READDIRPLUS_AUTO	(1 << 14)
+#define FUSE_ASYNC_DIO		(1 << 15)
 
 /**
  * CUSE INIT request/reply flags
@@ -173,6 +248,7 @@ struct fuse_file_lock {
  * Release flags
  */
 #define FUSE_RELEASE_FLUSH	(1 << 0)
+#define FUSE_RELEASE_FLOCK_UNLOCK	(1 << 1)
 
 /**
  * Getattr flags
@@ -204,12 +280,16 @@ struct fuse_file_lock {
  * FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
  * FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
  * FUSE_IOCTL_RETRY: retry with new iovecs
+ * FUSE_IOCTL_32BIT: 32bit ioctl
+ * FUSE_IOCTL_DIR: is a directory
  *
  * FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
  */
 #define FUSE_IOCTL_COMPAT	(1 << 0)
 #define FUSE_IOCTL_UNRESTRICTED	(1 << 1)
 #define FUSE_IOCTL_RETRY	(1 << 2)
+#define FUSE_IOCTL_32BIT	(1 << 3)
+#define FUSE_IOCTL_DIR		(1 << 4)
 
 #define FUSE_IOCTL_MAX_IOV	256
 
@@ -259,6 +339,10 @@ enum fuse_opcode {
 	FUSE_DESTROY       = 38,
 	FUSE_IOCTL         = 39,
 	FUSE_POLL          = 40,
+	FUSE_NOTIFY_REPLY  = 41,
+	FUSE_BATCH_FORGET  = 42,
+	FUSE_FALLOCATE     = 43,
+	FUSE_READDIRPLUS   = 44,
 
 	/* CUSE specific operations */
 	CUSE_INIT          = 4096,
@@ -268,6 +352,9 @@ enum fuse_notify_code {
 	FUSE_NOTIFY_POLL   = 1,
 	FUSE_NOTIFY_INVAL_INODE = 2,
 	FUSE_NOTIFY_INVAL_ENTRY = 3,
+	FUSE_NOTIFY_STORE = 4,
+	FUSE_NOTIFY_RETRIEVE = 5,
+	FUSE_NOTIFY_DELETE = 6,
 	FUSE_NOTIFY_CODE_MAX,
 };
 
@@ -277,133 +364,143 @@ enum fuse_notify_code {
 #define FUSE_COMPAT_ENTRY_OUT_SIZE 120
 
 struct fuse_entry_out {
-	__u64	nodeid;		/* Inode ID */
-	__u64	generation;	/* Inode generation: nodeid:gen must
-				   be unique for the fs's lifetime */
-	__u64	entry_valid;	/* Cache timeout for the name */
-	__u64	attr_valid;	/* Cache timeout for the attributes */
-	__u32	entry_valid_nsec;
-	__u32	attr_valid_nsec;
+	uint64_t	nodeid;		/* Inode ID */
+	uint64_t	generation;	/* Inode generation: nodeid:gen must
+					   be unique for the fs's lifetime */
+	uint64_t	entry_valid;	/* Cache timeout for the name */
+	uint64_t	attr_valid;	/* Cache timeout for the attributes */
+	uint32_t	entry_valid_nsec;
+	uint32_t	attr_valid_nsec;
 	struct fuse_attr attr;
 };
 
 struct fuse_forget_in {
-	__u64	nlookup;
+	uint64_t	nlookup;
+};
+
+struct fuse_forget_one {
+	uint64_t	nodeid;
+	uint64_t	nlookup;
+};
+
+struct fuse_batch_forget_in {
+	uint32_t	count;
+	uint32_t	dummy;
 };
 
 struct fuse_getattr_in {
-	__u32	getattr_flags;
-	__u32	dummy;
-	__u64	fh;
+	uint32_t	getattr_flags;
+	uint32_t	dummy;
+	uint64_t	fh;
 };
 
 #define FUSE_COMPAT_ATTR_OUT_SIZE 96
 
 struct fuse_attr_out {
-	__u64	attr_valid;	/* Cache timeout for the attributes */
-	__u32	attr_valid_nsec;
-	__u32	dummy;
+	uint64_t	attr_valid;	/* Cache timeout for the attributes */
+	uint32_t	attr_valid_nsec;
+	uint32_t	dummy;
 	struct fuse_attr attr;
 };
 
 #define FUSE_COMPAT_MKNOD_IN_SIZE 8
 
 struct fuse_mknod_in {
-	__u32	mode;
-	__u32	rdev;
-	__u32	umask;
-	__u32	padding;
+	uint32_t	mode;
+	uint32_t	rdev;
+	uint32_t	umask;
+	uint32_t	padding;
 };
 
 struct fuse_mkdir_in {
-	__u32	mode;
-	__u32	umask;
+	uint32_t	mode;
+	uint32_t	umask;
 };
 
 struct fuse_rename_in {
-	__u64	newdir;
+	uint64_t	newdir;
 };
 
 struct fuse_link_in {
-	__u64	oldnodeid;
+	uint64_t	oldnodeid;
 };
 
 struct fuse_setattr_in {
-	__u32	valid;
-	__u32	padding;
-	__u64	fh;
-	__u64	size;
-	__u64	lock_owner;
-	__u64	atime;
-	__u64	mtime;
-	__u64	unused2;
-	__u32	atimensec;
-	__u32	mtimensec;
-	__u32	unused3;
-	__u32	mode;
-	__u32	unused4;
-	__u32	uid;
-	__u32	gid;
-	__u32	unused5;
+	uint32_t	valid;
+	uint32_t	padding;
+	uint64_t	fh;
+	uint64_t	size;
+	uint64_t	lock_owner;
+	uint64_t	atime;
+	uint64_t	mtime;
+	uint64_t	unused2;
+	uint32_t	atimensec;
+	uint32_t	mtimensec;
+	uint32_t	unused3;
+	uint32_t	mode;
+	uint32_t	unused4;
+	uint32_t	uid;
+	uint32_t	gid;
+	uint32_t	unused5;
 };
 
 struct fuse_open_in {
-	__u32	flags;
-	__u32	unused;
+	uint32_t	flags;
+	uint32_t	unused;
 };
 
 struct fuse_create_in {
-	__u32	flags;
-	__u32	mode;
-	__u32	umask;
-	__u32	padding;
+	uint32_t	flags;
+	uint32_t	mode;
+	uint32_t	umask;
+	uint32_t	padding;
 };
 
 struct fuse_open_out {
-	__u64	fh;
-	__u32	open_flags;
-	__u32	padding;
+	uint64_t	fh;
+	uint32_t	open_flags;
+	uint32_t	padding;
 };
 
 struct fuse_release_in {
-	__u64	fh;
-	__u32	flags;
-	__u32	release_flags;
-	__u64	lock_owner;
+	uint64_t	fh;
+	uint32_t	flags;
+	uint32_t	release_flags;
+	uint64_t	lock_owner;
 };
 
 struct fuse_flush_in {
-	__u64	fh;
-	__u32	unused;
-	__u32	padding;
-	__u64	lock_owner;
+	uint64_t	fh;
+	uint32_t	unused;
+	uint32_t	padding;
+	uint64_t	lock_owner;
 };
 
 struct fuse_read_in {
-	__u64	fh;
-	__u64	offset;
-	__u32	size;
-	__u32	read_flags;
-	__u64	lock_owner;
-	__u32	flags;
-	__u32	padding;
+	uint64_t	fh;
+	uint64_t	offset;
+	uint32_t	size;
+	uint32_t	read_flags;
+	uint64_t	lock_owner;
+	uint32_t	flags;
+	uint32_t	padding;
 };
 
 #define FUSE_COMPAT_WRITE_IN_SIZE 24
 
 struct fuse_write_in {
-	__u64	fh;
-	__u64	offset;
-	__u32	size;
-	__u32	write_flags;
-	__u64	lock_owner;
-	__u32	flags;
-	__u32	padding;
+	uint64_t	fh;
+	uint64_t	offset;
+	uint32_t	size;
+	uint32_t	write_flags;
+	uint64_t	lock_owner;
+	uint32_t	flags;
+	uint32_t	padding;
 };
 
 struct fuse_write_out {
-	__u32	size;
-	__u32	padding;
+	uint32_t	size;
+	uint32_t	padding;
 };
 
 #define FUSE_COMPAT_STATFS_SIZE 48
@@ -413,32 +510,32 @@ struct fuse_statfs_out {
 };
 
 struct fuse_fsync_in {
-	__u64	fh;
-	__u32	fsync_flags;
-	__u32	padding;
+	uint64_t	fh;
+	uint32_t	fsync_flags;
+	uint32_t	padding;
 };
 
 struct fuse_setxattr_in {
-	__u32	size;
-	__u32	flags;
+	uint32_t	size;
+	uint32_t	flags;
 };
 
 struct fuse_getxattr_in {
-	__u32	size;
-	__u32	padding;
+	uint32_t	size;
+	uint32_t	padding;
 };
 
 struct fuse_getxattr_out {
-	__u32	size;
-	__u32	padding;
+	uint32_t	size;
+	uint32_t	padding;
 };
 
 struct fuse_lk_in {
-	__u64	fh;
-	__u64	owner;
+	uint64_t	fh;
+	uint64_t	owner;
 	struct fuse_file_lock lk;
-	__u32	lk_flags;
-	__u32	padding;
+	uint32_t	lk_flags;
+	uint32_t	padding;
 };
 
 struct fuse_lk_out {
@@ -446,134 +543,190 @@ struct fuse_lk_out {
 };
 
 struct fuse_access_in {
-	__u32	mask;
-	__u32	padding;
+	uint32_t	mask;
+	uint32_t	padding;
 };
 
 struct fuse_init_in {
-	__u32	major;
-	__u32	minor;
-	__u32	max_readahead;
-	__u32	flags;
+	uint32_t	major;
+	uint32_t	minor;
+	uint32_t	max_readahead;
+	uint32_t	flags;
 };
 
 struct fuse_init_out {
-	__u32	major;
-	__u32	minor;
-	__u32	max_readahead;
-	__u32	flags;
-	__u16   max_background;
-	__u16   congestion_threshold;
-	__u32	max_write;
+	uint32_t	major;
+	uint32_t	minor;
+	uint32_t	max_readahead;
+	uint32_t	flags;
+	uint16_t	max_background;
+	uint16_t	congestion_threshold;
+	uint32_t	max_write;
 };
 
 #define CUSE_INIT_INFO_MAX 4096
 
 struct cuse_init_in {
-	__u32	major;
-	__u32	minor;
-	__u32	unused;
-	__u32	flags;
+	uint32_t	major;
+	uint32_t	minor;
+	uint32_t	unused;
+	uint32_t	flags;
 };
 
 struct cuse_init_out {
-	__u32	major;
-	__u32	minor;
-	__u32	unused;
-	__u32	flags;
-	__u32	max_read;
-	__u32	max_write;
-	__u32	dev_major;		/* chardev major */
-	__u32	dev_minor;		/* chardev minor */
-	__u32	spare[10];
+	uint32_t	major;
+	uint32_t	minor;
+	uint32_t	unused;
+	uint32_t	flags;
+	uint32_t	max_read;
+	uint32_t	max_write;
+	uint32_t	dev_major;		/* chardev major */
+	uint32_t	dev_minor;		/* chardev minor */
+	uint32_t	spare[10];
 };
 
 struct fuse_interrupt_in {
-	__u64	unique;
+	uint64_t	unique;
 };
 
 struct fuse_bmap_in {
-	__u64	block;
-	__u32	blocksize;
-	__u32	padding;
+	uint64_t	block;
+	uint32_t	blocksize;
+	uint32_t	padding;
 };
 
 struct fuse_bmap_out {
-	__u64	block;
+	uint64_t	block;
 };
 
 struct fuse_ioctl_in {
-	__u64	fh;
-	__u32	flags;
-	__u32	cmd;
-	__u64	arg;
-	__u32	in_size;
-	__u32	out_size;
+	uint64_t	fh;
+	uint32_t	flags;
+	uint32_t	cmd;
+	uint64_t	arg;
+	uint32_t	in_size;
+	uint32_t	out_size;
+};
+
+struct fuse_ioctl_iovec {
+	uint64_t	base;
+	uint64_t	len;
 };
 
 struct fuse_ioctl_out {
-	__s32	result;
-	__u32	flags;
-	__u32	in_iovs;
-	__u32	out_iovs;
+	int32_t		result;
+	uint32_t	flags;
+	uint32_t	in_iovs;
+	uint32_t	out_iovs;
 };
 
 struct fuse_poll_in {
-	__u64	fh;
-	__u64	kh;
-	__u32	flags;
-	__u32   padding;
+	uint64_t	fh;
+	uint64_t	kh;
+	uint32_t	flags;
+	uint32_t	events;
 };
 
 struct fuse_poll_out {
-	__u32	revents;
-	__u32	padding;
+	uint32_t	revents;
+	uint32_t	padding;
 };
 
 struct fuse_notify_poll_wakeup_out {
-	__u64	kh;
+	uint64_t	kh;
+};
+
+struct fuse_fallocate_in {
+	uint64_t	fh;
+	uint64_t	offset;
+	uint64_t	length;
+	uint32_t	mode;
+	uint32_t	padding;
 };
 
 struct fuse_in_header {
-	__u32	len;
-	__u32	opcode;
-	__u64	unique;
-	__u64	nodeid;
-	__u32	uid;
-	__u32	gid;
-	__u32	pid;
-	__u32	padding;
+	uint32_t	len;
+	uint32_t	opcode;
+	uint64_t	unique;
+	uint64_t	nodeid;
+	uint32_t	uid;
+	uint32_t	gid;
+	uint32_t	pid;
+	uint32_t	padding;
 };
 
 struct fuse_out_header {
-	__u32	len;
-	__s32	error;
-	__u64	unique;
+	uint32_t	len;
+	int32_t		error;
+	uint64_t	unique;
 };
 
 struct fuse_dirent {
-	__u64	ino;
-	__u64	off;
-	__u32	namelen;
-	__u32	type;
-	char name[0];
+	uint64_t	ino;
+	uint64_t	off;
+	uint32_t	namelen;
+	uint32_t	type;
+	char name[];
 };
 
 #define FUSE_NAME_OFFSET offsetof(struct fuse_dirent, name)
-#define FUSE_DIRENT_ALIGN(x) (((x) + sizeof(__u64) - 1) & ~(sizeof(__u64) - 1))
+#define FUSE_DIRENT_ALIGN(x) \
+	(((x) + sizeof(uint64_t) - 1) & ~(sizeof(uint64_t) - 1))
 #define FUSE_DIRENT_SIZE(d) \
 	FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET + (d)->namelen)
 
+struct fuse_direntplus {
+	struct fuse_entry_out entry_out;
+	struct fuse_dirent dirent;
+};
+
+#define FUSE_NAME_OFFSET_DIRENTPLUS \
+	offsetof(struct fuse_direntplus, dirent.name)
+#define FUSE_DIRENTPLUS_SIZE(d) \
+	FUSE_DIRENT_ALIGN(FUSE_NAME_OFFSET_DIRENTPLUS + (d)->dirent.namelen)
+
 struct fuse_notify_inval_inode_out {
-	__u64	ino;
-	__s64	off;
-	__s64	len;
+	uint64_t	ino;
+	int64_t		off;
+	int64_t		len;
 };
 
 struct fuse_notify_inval_entry_out {
-	__u64	parent;
-	__u32	namelen;
-	__u32	padding;
+	uint64_t	parent;
+	uint32_t	namelen;
+	uint32_t	padding;
+};
+
+struct fuse_notify_delete_out {
+	uint64_t	parent;
+	uint64_t	child;
+	uint32_t	namelen;
+	uint32_t	padding;
+};
+
+struct fuse_notify_store_out {
+	uint64_t	nodeid;
+	uint64_t	offset;
+	uint32_t	size;
+	uint32_t	padding;
+};
+
+struct fuse_notify_retrieve_out {
+	uint64_t	notify_unique;
+	uint64_t	nodeid;
+	uint64_t	offset;
+	uint32_t	size;
+	uint32_t	padding;
+};
+
+/* Matches the size of fuse_write_in */
+struct fuse_notify_retrieve_in {
+	uint64_t	dummy1;
+	uint64_t	offset;
+	uint32_t	size;
+	uint32_t	dummy2;
+	uint64_t	dummy3;
+	uint64_t	dummy4;
 };
 
 #endif /* _LINUX_FUSE_H */
diff --git a/contrib/fuse-lib/mount-gluster-compat.h b/contrib/fuse-lib/mount-gluster-compat.h
index 17c11e789..4fc20623b 100644
--- a/contrib/fuse-lib/mount-gluster-compat.h
+++ b/contrib/fuse-lib/mount-gluster-compat.h
@@ -33,6 +33,7 @@
 #ifdef __NetBSD__
 #include <perfuse.h>
 #define umount2(dir, flags) unmount(dir, ((flags) != 0) ? MNT_FORCE : 0)
+#define MS_RDONLY MNT_RDONLY
 #endif
 
 #ifdef linux
diff --git a/contrib/fuse-lib/mount.c b/contrib/fuse-lib/mount.c
index fedde3fce..922d9e464 100644
--- a/contrib/fuse-lib/mount.c
+++ b/contrib/fuse-lib/mount.c
@@ -201,7 +201,7 @@ fuse_mount_sys (const char *mountpoint, char *fsname,
 
                         goto out;
                 }
-                ret = mount (source, mountpoint, fstype, 0,
+                ret = mount (source, mountpoint, fstype, mountflags,
                              mnt_param_mnt);
         }
         if (ret == -1)
@@ -294,7 +294,8 @@ gf_fuse_mount (const char *mountpoint, char *fsname,
                 }
 
                 if (ret == -1)
-                        GFFUSE_LOGERR ("mount failed");
+                        GFFUSE_LOGERR ("mount of %s to %s (%s) failed",
+                                       fsname, mountpoint, mnt_param);
 
                 if (status_fd >= 0)
                         (void)write (status_fd, &ret, sizeof (ret));
diff --git a/contrib/libgen/basename_r.c b/contrib/libgen/basename_r.c
index d63bce4e5..2c3a87afe 100644
--- a/contrib/libgen/basename_r.c
+++ b/contrib/libgen/basename_r.c
@@ -1,10 +1,10 @@
-#ifdef THREAD_UNSAFE_BASENAME
 /*
- * borrowed from glibc-2.12.1/string/basename.c 
+ * borrowed from glibc-2.12.1/string/basename.c
  * Modified to return "." for NULL or "", as required for SUSv2.
  */
 #include <string.h>
 #include <stdlib.h>
+#ifdef THREAD_UNSAFE_BASENAME
 
 /* Return the name-within-directory of a file name.
    Copyright (C) 1996,97,98,2002 Free Software Foundation, Inc.
diff --git a/contrib/libgen/dirname_r.c b/contrib/libgen/dirname_r.c
index 02981f5ec..131cbcf2a 100644
--- a/contrib/libgen/dirname_r.c
+++ b/contrib/libgen/dirname_r.c
@@ -1,4 +1,3 @@
-#ifdef THREAD_UNSAFE_DIRNAME
 /*
  * Borrowed from glibc-2.12.1/string/memrchr.c
  * Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
@@ -7,6 +6,7 @@
  */
 #include <string.h>
 #include <stdlib.h>
+#ifdef THREAD_UNSAFE_DIRNAME
 
 /* memrchr -- find the last occurrence of a byte in a memory block
    Copyright (C) 1991, 93, 96, 97, 99, 2000 Free Software Foundation, Inc.
diff --git a/contrib/qemu/block.c b/contrib/qemu/block.c
new file mode 100644
index 000000000..b56024113
--- /dev/null
+++ b/contrib/qemu/block.c
@@ -0,0 +1,4604 @@
+/*
+ * QEMU System Emulator block driver
+ *
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "config-host.h"
+#include "qemu-common.h"
+#include "trace.h"
+#include "monitor/monitor.h"
+#include "block/block_int.h"
+#include "block/blockjob.h"
+#include "qemu/module.h"
+#include "qapi/qmp/qjson.h"
+#include "sysemu/sysemu.h"
+#include "qemu/notify.h"
+#include "block/coroutine.h"
+#include "qmp-commands.h"
+#include "qemu/timer.h"
+
+#ifdef CONFIG_BSD
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <sys/queue.h>
+#ifndef __DragonFly__
+#include <sys/disk.h>
+#endif
+#endif
+
+#ifdef _WIN32
+#include <windows.h>
+#endif
+
+#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
+
+typedef enum {
+    BDRV_REQ_COPY_ON_READ = 0x1,
+    BDRV_REQ_ZERO_WRITE   = 0x2,
+} BdrvRequestFlags;
+
+static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load);
+static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
+        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+        BlockDriverCompletionFunc *cb, void *opaque);
+static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
+        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+        BlockDriverCompletionFunc *cb, void *opaque);
+static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
+                                         int64_t sector_num, int nb_sectors,
+                                         QEMUIOVector *iov);
+static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
+                                         int64_t sector_num, int nb_sectors,
+                                         QEMUIOVector *iov);
+static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
+    BdrvRequestFlags flags);
+static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
+    BdrvRequestFlags flags);
+static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
+                                               int64_t sector_num,
+                                               QEMUIOVector *qiov,
+                                               int nb_sectors,
+                                               BlockDriverCompletionFunc *cb,
+                                               void *opaque,
+                                               bool is_write);
+static void coroutine_fn bdrv_co_do_rw(void *opaque);
+static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors);
+
+static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors,
+        bool is_write, double elapsed_time, uint64_t *wait);
+static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write,
+        double elapsed_time, uint64_t *wait);
+static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors,
+        bool is_write, int64_t *wait);
+
+static QTAILQ_HEAD(, BlockDriverState) bdrv_states =
+    QTAILQ_HEAD_INITIALIZER(bdrv_states);
+
+static QLIST_HEAD(, BlockDriver) bdrv_drivers =
+    QLIST_HEAD_INITIALIZER(bdrv_drivers);
+
+/* If non-zero, use only whitelisted block drivers */
+static int use_bdrv_whitelist;
+
+#ifdef _WIN32
+static int is_windows_drive_prefix(const char *filename)
+{
+    return (((filename[0] >= 'a' && filename[0] <= 'z') ||
+             (filename[0] >= 'A' && filename[0] <= 'Z')) &&
+            filename[1] == ':');
+}
+
+int is_windows_drive(const char *filename)
+{
+    if (is_windows_drive_prefix(filename) &&
+        filename[2] == '\0')
+        return 1;
+    if (strstart(filename, "\\\\.\\", NULL) ||
+        strstart(filename, "//./", NULL))
+        return 1;
+    return 0;
+}
+#endif
+
+/* throttling disk I/O limits */
+void bdrv_io_limits_disable(BlockDriverState *bs)
+{
+    bs->io_limits_enabled = false;
+
+    while (qemu_co_queue_next(&bs->throttled_reqs));
+
+    if (bs->block_timer) {
+        qemu_del_timer(bs->block_timer);
+        qemu_free_timer(bs->block_timer);
+        bs->block_timer = NULL;
+    }
+
+    bs->slice_start = 0;
+    bs->slice_end   = 0;
+}
+
+static void bdrv_block_timer(void *opaque)
+{
+    BlockDriverState *bs = opaque;
+
+    qemu_co_queue_next(&bs->throttled_reqs);
+}
+
+void bdrv_io_limits_enable(BlockDriverState *bs)
+{
+    qemu_co_queue_init(&bs->throttled_reqs);
+    bs->block_timer = qemu_new_timer_ns(vm_clock, bdrv_block_timer, bs);
+    bs->io_limits_enabled = true;
+}
+
+bool bdrv_io_limits_enabled(BlockDriverState *bs)
+{
+    BlockIOLimit *io_limits = &bs->io_limits;
+    return io_limits->bps[BLOCK_IO_LIMIT_READ]
+         || io_limits->bps[BLOCK_IO_LIMIT_WRITE]
+         || io_limits->bps[BLOCK_IO_LIMIT_TOTAL]
+         || io_limits->iops[BLOCK_IO_LIMIT_READ]
+         || io_limits->iops[BLOCK_IO_LIMIT_WRITE]
+         || io_limits->iops[BLOCK_IO_LIMIT_TOTAL];
+}
+
+static void bdrv_io_limits_intercept(BlockDriverState *bs,
+                                     bool is_write, int nb_sectors)
+{
+    int64_t wait_time = -1;
+
+    if (!qemu_co_queue_empty(&bs->throttled_reqs)) {
+        qemu_co_queue_wait(&bs->throttled_reqs);
+    }
+
+    /* In fact, we hope to keep each request's timing, in FIFO mode. The next
+     * throttled requests will not be dequeued until the current request is
+     * allowed to be serviced. So if the current request still exceeds the
+     * limits, it will be inserted to the head. All requests followed it will
+     * be still in throttled_reqs queue.
+     */
+
+    while (bdrv_exceed_io_limits(bs, nb_sectors, is_write, &wait_time)) {
+        qemu_mod_timer(bs->block_timer,
+                       wait_time + qemu_get_clock_ns(vm_clock));
+        qemu_co_queue_wait_insert_head(&bs->throttled_reqs);
+    }
+
+    qemu_co_queue_next(&bs->throttled_reqs);
+}
+
+/* check if the path starts with "<protocol>:" */
+static int path_has_protocol(const char *path)
+{
+    const char *p;
+
+#ifdef _WIN32
+    if (is_windows_drive(path) ||
+        is_windows_drive_prefix(path)) {
+        return 0;
+    }
+    p = path + strcspn(path, ":/\\");
+#else
+    p = path + strcspn(path, ":/");
+#endif
+
+    return *p == ':';
+}
+
+int path_is_absolute(const char *path)
+{
+#ifdef _WIN32
+    /* specific case for names like: "\\.\d:" */
+    if (is_windows_drive(path) || is_windows_drive_prefix(path)) {
+        return 1;
+    }
+    return (*path == '/' || *path == '\\');
+#else
+    return (*path == '/');
+#endif
+}
+
+/* if filename is absolute, just copy it to dest. Otherwise, build a
+   path to it by considering it is relative to base_path. URL are
+   supported. */
+void path_combine(char *dest, int dest_size,
+                  const char *base_path,
+                  const char *filename)
+{
+    const char *p, *p1;
+    int len;
+
+    if (dest_size <= 0)
+        return;
+    if (path_is_absolute(filename)) {
+        pstrcpy(dest, dest_size, filename);
+    } else {
+        p = strchr(base_path, ':');
+        if (p)
+            p++;
+        else
+            p = base_path;
+        p1 = strrchr(base_path, '/');
+#ifdef _WIN32
+        {
+            const char *p2;
+            p2 = strrchr(base_path, '\\');
+            if (!p1 || p2 > p1)
+                p1 = p2;
+        }
+#endif
+        if (p1)
+            p1++;
+        else
+            p1 = base_path;
+        if (p1 > p)
+            p = p1;
+        len = p - base_path;
+        if (len > dest_size - 1)
+            len = dest_size - 1;
+        memcpy(dest, base_path, len);
+        dest[len] = '\0';
+        pstrcat(dest, dest_size, filename);
+    }
+}
+
+void bdrv_get_full_backing_filename(BlockDriverState *bs, char *dest, size_t sz)
+{
+    if (bs->backing_file[0] == '\0' || path_has_protocol(bs->backing_file)) {
+        pstrcpy(dest, sz, bs->backing_file);
+    } else {
+        path_combine(dest, sz, bs->filename, bs->backing_file);
+    }
+}
+
+void bdrv_register(BlockDriver *bdrv)
+{
+    /* Block drivers without coroutine functions need emulation */
+    if (!bdrv->bdrv_co_readv) {
+        bdrv->bdrv_co_readv = bdrv_co_readv_em;
+        bdrv->bdrv_co_writev = bdrv_co_writev_em;
+
+        /* bdrv_co_readv_em()/brdv_co_writev_em() work in terms of aio, so if
+         * the block driver lacks aio we need to emulate that too.
+         */
+        if (!bdrv->bdrv_aio_readv) {
+            /* add AIO emulation layer */
+            bdrv->bdrv_aio_readv = bdrv_aio_readv_em;
+            bdrv->bdrv_aio_writev = bdrv_aio_writev_em;
+        }
+    }
+
+    QLIST_INSERT_HEAD(&bdrv_drivers, bdrv, list);
+}
+
+/* create a new block device (by default it is empty) */
+BlockDriverState *bdrv_new(const char *device_name)
+{
+    BlockDriverState *bs;
+
+    bs = g_malloc0(sizeof(BlockDriverState));
+    pstrcpy(bs->device_name, sizeof(bs->device_name), device_name);
+    if (device_name[0] != '\0') {
+        QTAILQ_INSERT_TAIL(&bdrv_states, bs, list);
+    }
+    bdrv_iostatus_disable(bs);
+    notifier_list_init(&bs->close_notifiers);
+    notifier_with_return_list_init(&bs->before_write_notifiers);
+
+    return bs;
+}
+
+void bdrv_add_close_notifier(BlockDriverState *bs, Notifier *notify)
+{
+    notifier_list_add(&bs->close_notifiers, notify);
+}
+
+BlockDriver *bdrv_find_format(const char *format_name)
+{
+    BlockDriver *drv1;
+    QLIST_FOREACH(drv1, &bdrv_drivers, list) {
+        if (!strcmp(drv1->format_name, format_name)) {
+            return drv1;
+        }
+    }
+    return NULL;
+}
+
+static int bdrv_is_whitelisted(BlockDriver *drv, bool read_only)
+{
+    static const char *whitelist_rw[] = {
+        CONFIG_BDRV_RW_WHITELIST
+    };
+    static const char *whitelist_ro[] = {
+        CONFIG_BDRV_RO_WHITELIST
+    };
+    const char **p;
+
+    if (!whitelist_rw[0] && !whitelist_ro[0]) {
+        return 1;               /* no whitelist, anything goes */
+    }
+
+    for (p = whitelist_rw; *p; p++) {
+        if (!strcmp(drv->format_name, *p)) {
+            return 1;
+        }
+    }
+    if (read_only) {
+        for (p = whitelist_ro; *p; p++) {
+            if (!strcmp(drv->format_name, *p)) {
+                return 1;
+            }
+        }
+    }
+    return 0;
+}
+
+BlockDriver *bdrv_find_whitelisted_format(const char *format_name,
+                                          bool read_only)
+{
+    BlockDriver *drv = bdrv_find_format(format_name);
+    return drv && bdrv_is_whitelisted(drv, read_only) ? drv : NULL;
+}
+
+typedef struct CreateCo {
+    BlockDriver *drv;
+    char *filename;
+    QEMUOptionParameter *options;
+    int ret;
+} CreateCo;
+
+static void coroutine_fn bdrv_create_co_entry(void *opaque)
+{
+    CreateCo *cco = opaque;
+    assert(cco->drv);
+
+    cco->ret = cco->drv->bdrv_create(cco->filename, cco->options);
+}
+
+int bdrv_create(BlockDriver *drv, const char* filename,
+    QEMUOptionParameter *options)
+{
+    int ret;
+
+    Coroutine *co;
+    CreateCo cco = {
+        .drv = drv,
+        .filename = g_strdup(filename),
+        .options = options,
+        .ret = NOT_DONE,
+    };
+
+    if (!drv->bdrv_create) {
+        ret = -ENOTSUP;
+        goto out;
+    }
+
+    if (qemu_in_coroutine()) {
+        /* Fast-path if already in coroutine context */
+        bdrv_create_co_entry(&cco);
+    } else {
+        co = qemu_coroutine_create(bdrv_create_co_entry);
+        qemu_coroutine_enter(co, &cco);
+        while (cco.ret == NOT_DONE) {
+            qemu_aio_wait();
+        }
+    }
+
+    ret = cco.ret;
+
+out:
+    g_free(cco.filename);
+    return ret;
+}
+
+int bdrv_create_file(const char* filename, QEMUOptionParameter *options)
+{
+    BlockDriver *drv;
+
+    drv = bdrv_find_protocol(filename, true);
+    if (drv == NULL) {
+        return -ENOENT;
+    }
+
+    return bdrv_create(drv, filename, options);
+}
+
+/*
+ * Create a uniquely-named empty temporary file.
+ * Return 0 upon success, otherwise a negative errno value.
+ */
+int get_tmp_filename(char *filename, int size)
+{
+#ifdef _WIN32
+    char temp_dir[MAX_PATH];
+    /* GetTempFileName requires that its output buffer (4th param)
+       have length MAX_PATH or greater.  */
+    assert(size >= MAX_PATH);
+    return (GetTempPath(MAX_PATH, temp_dir)
+            && GetTempFileName(temp_dir, "qem", 0, filename)
+            ? 0 : -GetLastError());
+#else
+    int fd;
+    const char *tmpdir;
+    tmpdir = getenv("TMPDIR");
+    if (!tmpdir)
+        tmpdir = "/tmp";
+    if (snprintf(filename, size, "%s/vl.XXXXXX", tmpdir) >= size) {
+        return -EOVERFLOW;
+    }
+    fd = mkstemp(filename);
+    if (fd < 0) {
+        return -errno;
+    }
+    if (close(fd) != 0) {
+        unlink(filename);
+        return -errno;
+    }
+    return 0;
+#endif
+}
+
+/*
+ * Detect host devices. By convention, /dev/cdrom[N] is always
+ * recognized as a host CDROM.
+ */
+static BlockDriver *find_hdev_driver(const char *filename)
+{
+    int score_max = 0, score;
+    BlockDriver *drv = NULL, *d;
+
+    QLIST_FOREACH(d, &bdrv_drivers, list) {
+        if (d->bdrv_probe_device) {
+            score = d->bdrv_probe_device(filename);
+            if (score > score_max) {
+                score_max = score;
+                drv = d;
+            }
+        }
+    }
+
+    return drv;
+}
+
+BlockDriver *bdrv_find_protocol(const char *filename,
+                                bool allow_protocol_prefix)
+{
+    BlockDriver *drv1;
+    char protocol[128];
+    int len;
+    const char *p;
+
+    /* TODO Drivers without bdrv_file_open must be specified explicitly */
+
+    /*
+     * XXX(hch): we really should not let host device detection
+     * override an explicit protocol specification, but moving this
+     * later breaks access to device names with colons in them.
+     * Thanks to the brain-dead persistent naming schemes on udev-
+     * based Linux systems those actually are quite common.
+     */
+    drv1 = find_hdev_driver(filename);
+    if (drv1) {
+        return drv1;
+    }
+
+    if (!path_has_protocol(filename) || !allow_protocol_prefix) {
+        return bdrv_find_format("file");
+    }
+
+    p = strchr(filename, ':');
+    assert(p != NULL);
+    len = p - filename;
+    if (len > sizeof(protocol) - 1)
+        len = sizeof(protocol) - 1;
+    memcpy(protocol, filename, len);
+    protocol[len] = '\0';
+    QLIST_FOREACH(drv1, &bdrv_drivers, list) {
+        if (drv1->protocol_name &&
+            !strcmp(drv1->protocol_name, protocol)) {
+            return drv1;
+        }
+    }
+    return NULL;
+}
+
+static int find_image_format(BlockDriverState *bs, const char *filename,
+                             BlockDriver **pdrv)
+{
+    int score, score_max;
+    BlockDriver *drv1, *drv;
+    uint8_t buf[2048];
+    int ret = 0;
+
+    /* Return the raw BlockDriver * to scsi-generic devices or empty drives */
+    if (bs->sg || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) {
+        drv = bdrv_find_format("raw");
+        if (!drv) {
+            ret = -ENOENT;
+        }
+        *pdrv = drv;
+        return ret;
+    }
+
+    ret = bdrv_pread(bs, 0, buf, sizeof(buf));
+    if (ret < 0) {
+        *pdrv = NULL;
+        return ret;
+    }
+
+    score_max = 0;
+    drv = NULL;
+    QLIST_FOREACH(drv1, &bdrv_drivers, list) {
+        if (drv1->bdrv_probe) {
+            score = drv1->bdrv_probe(buf, ret, filename);
+            if (score > score_max) {
+                score_max = score;
+                drv = drv1;
+            }
+        }
+    }
+    if (!drv) {
+        ret = -ENOENT;
+    }
+    *pdrv = drv;
+    return ret;
+}
+
+/**
+ * Set the current 'total_sectors' value
+ */
+static int refresh_total_sectors(BlockDriverState *bs, int64_t hint)
+{
+    BlockDriver *drv = bs->drv;
+
+    /* Do not attempt drv->bdrv_getlength() on scsi-generic devices */
+    if (bs->sg)
+        return 0;
+
+    /* query actual device if possible, otherwise just trust the hint */
+    if (drv->bdrv_getlength) {
+        int64_t length = drv->bdrv_getlength(bs);
+        if (length < 0) {
+            return length;
+        }
+        hint = length >> BDRV_SECTOR_BITS;
+    }
+
+    bs->total_sectors = hint;
+    return 0;
+}
+
+/**
+ * Set open flags for a given discard mode
+ *
+ * Return 0 on success, -1 if the discard mode was invalid.
+ */
+int bdrv_parse_discard_flags(const char *mode, int *flags)
+{
+    *flags &= ~BDRV_O_UNMAP;
+
+    if (!strcmp(mode, "off") || !strcmp(mode, "ignore")) {
+        /* do nothing */
+    } else if (!strcmp(mode, "on") || !strcmp(mode, "unmap")) {
+        *flags |= BDRV_O_UNMAP;
+    } else {
+        return -1;
+    }
+
+    return 0;
+}
+
+/**
+ * Set open flags for a given cache mode
+ *
+ * Return 0 on success, -1 if the cache mode was invalid.
+ */
+int bdrv_parse_cache_flags(const char *mode, int *flags)
+{
+    *flags &= ~BDRV_O_CACHE_MASK;
+
+    if (!strcmp(mode, "off") || !strcmp(mode, "none")) {
+        *flags |= BDRV_O_NOCACHE | BDRV_O_CACHE_WB;
+    } else if (!strcmp(mode, "directsync")) {
+        *flags |= BDRV_O_NOCACHE;
+    } else if (!strcmp(mode, "writeback")) {
+        *flags |= BDRV_O_CACHE_WB;
+    } else if (!strcmp(mode, "unsafe")) {
+        *flags |= BDRV_O_CACHE_WB;
+        *flags |= BDRV_O_NO_FLUSH;
+    } else if (!strcmp(mode, "writethrough")) {
+        /* this is the default */
+    } else {
+        return -1;
+    }
+
+    return 0;
+}
+
+/**
+ * The copy-on-read flag is actually a reference count so multiple users may
+ * use the feature without worrying about clobbering its previous state.
+ * Copy-on-read stays enabled until all users have called to disable it.
+ */
+void bdrv_enable_copy_on_read(BlockDriverState *bs)
+{
+    bs->copy_on_read++;
+}
+
+void bdrv_disable_copy_on_read(BlockDriverState *bs)
+{
+    assert(bs->copy_on_read > 0);
+    bs->copy_on_read--;
+}
+
+static int bdrv_open_flags(BlockDriverState *bs, int flags)
+{
+    int open_flags = flags | BDRV_O_CACHE_WB;
+
+    /*
+     * Clear flags that are internal to the block layer before opening the
+     * image.
+     */
+    open_flags &= ~(BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
+
+    /*
+     * Snapshots should be writable.
+     */
+    if (bs->is_temporary) {
+        open_flags |= BDRV_O_RDWR;
+    }
+
+    return open_flags;
+}
+
+/*
+ * Common part for opening disk images and files
+ *
+ * Removes all processed options from *options.
+ */
+static int bdrv_open_common(BlockDriverState *bs, BlockDriverState *file,
+    QDict *options, int flags, BlockDriver *drv)
+{
+    int ret, open_flags;
+    const char *filename;
+
+    assert(drv != NULL);
+    assert(bs->file == NULL);
+    assert(options != NULL && bs->options != options);
+
+    if (file != NULL) {
+        filename = file->filename;
+    } else {
+        filename = qdict_get_try_str(options, "filename");
+    }
+
+    trace_bdrv_open_common(bs, filename ?: "", flags, drv->format_name);
+
+    /* bdrv_open() with directly using a protocol as drv. This layer is already
+     * opened, so assign it to bs (while file becomes a closed BlockDriverState)
+     * and return immediately. */
+    if (file != NULL && drv->bdrv_file_open) {
+        bdrv_swap(file, bs);
+        return 0;
+    }
+
+    bs->open_flags = flags;
+    bs->buffer_alignment = 512;
+    open_flags = bdrv_open_flags(bs, flags);
+    bs->read_only = !(open_flags & BDRV_O_RDWR);
+
+    if (use_bdrv_whitelist && !bdrv_is_whitelisted(drv, bs->read_only)) {
+        return -ENOTSUP;
+    }
+
+    assert(bs->copy_on_read == 0); /* bdrv_new() and bdrv_close() make it so */
+    if (!bs->read_only && (flags & BDRV_O_COPY_ON_READ)) {
+        bdrv_enable_copy_on_read(bs);
+    }
+
+    if (filename != NULL) {
+        pstrcpy(bs->filename, sizeof(bs->filename), filename);
+    } else {
+        bs->filename[0] = '\0';
+    }
+
+    bs->drv = drv;
+    bs->opaque = g_malloc0(drv->instance_size);
+
+    bs->enable_write_cache = !!(flags & BDRV_O_CACHE_WB);
+
+    /* Open the image, either directly or using a protocol */
+    if (drv->bdrv_file_open) {
+        assert(file == NULL);
+        assert(drv->bdrv_parse_filename || filename != NULL);
+        ret = drv->bdrv_file_open(bs, options, open_flags);
+    } else {
+        if (file == NULL) {
+            qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't use '%s' as a "
+                          "block driver for the protocol level",
+                          drv->format_name);
+            ret = -EINVAL;
+            goto free_and_fail;
+        }
+        assert(file != NULL);
+        bs->file = file;
+        ret = drv->bdrv_open(bs, options, open_flags);
+    }
+
+    if (ret < 0) {
+        goto free_and_fail;
+    }
+
+    ret = refresh_total_sectors(bs, bs->total_sectors);
+    if (ret < 0) {
+        goto free_and_fail;
+    }
+
+#ifndef _WIN32
+    if (bs->is_temporary) {
+        assert(filename != NULL);
+        unlink(filename);
+    }
+#endif
+    return 0;
+
+free_and_fail:
+    bs->file = NULL;
+    g_free(bs->opaque);
+    bs->opaque = NULL;
+    bs->drv = NULL;
+    return ret;
+}
+
+/*
+ * Opens a file using a protocol (file, host_device, nbd, ...)
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use QINCREF() before calling bdrv_file_open.
+ */
+int bdrv_file_open(BlockDriverState **pbs, const char *filename,
+                   QDict *options, int flags)
+{
+    BlockDriverState *bs;
+    BlockDriver *drv;
+    const char *drvname;
+    bool allow_protocol_prefix = false;
+    int ret;
+
+    /* NULL means an empty set of options */
+    if (options == NULL) {
+        options = qdict_new();
+    }
+
+    bs = bdrv_new("");
+    bs->options = options;
+    options = qdict_clone_shallow(options);
+
+    /* Fetch the file name from the options QDict if necessary */
+    if (!filename) {
+        filename = qdict_get_try_str(options, "filename");
+    } else if (filename && !qdict_haskey(options, "filename")) {
+        qdict_put(options, "filename", qstring_from_str(filename));
+        allow_protocol_prefix = true;
+    } else {
+        qerror_report(ERROR_CLASS_GENERIC_ERROR, "Can't specify 'file' and "
+                      "'filename' options at the same time");
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* Find the right block driver */
+    drvname = qdict_get_try_str(options, "driver");
+    if (drvname) {
+        drv = bdrv_find_whitelisted_format(drvname, !(flags & BDRV_O_RDWR));
+        qdict_del(options, "driver");
+    } else if (filename) {
+        drv = bdrv_find_protocol(filename, allow_protocol_prefix);
+        if (!drv) {
+            qerror_report(ERROR_CLASS_GENERIC_ERROR, "Unknown protocol");
+        }
+    } else {
+        qerror_report(ERROR_CLASS_GENERIC_ERROR,
+                      "Must specify either driver or file");
+        drv = NULL;
+    }
+
+    if (!drv) {
+        ret = -ENOENT;
+        goto fail;
+    }
+
+    /* Parse the filename and open it */
+    if (drv->bdrv_parse_filename && filename) {
+        Error *local_err = NULL;
+        drv->bdrv_parse_filename(filename, options, &local_err);
+        if (error_is_set(&local_err)) {
+            qerror_report_err(local_err);
+            error_free(local_err);
+            ret = -EINVAL;
+            goto fail;
+        }
+        qdict_del(options, "filename");
+    } else if (!drv->bdrv_parse_filename && !filename) {
+        qerror_report(ERROR_CLASS_GENERIC_ERROR,
+                      "The '%s' block driver requires a file name",
+                      drv->format_name);
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    ret = bdrv_open_common(bs, NULL, options, flags, drv);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Check if any unknown options were used */
+    if (qdict_size(options) != 0) {
+        const QDictEntry *entry = qdict_first(options);
+        qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block protocol '%s' doesn't "
+                      "support the option '%s'",
+                      drv->format_name, entry->key);
+        ret = -EINVAL;
+        goto fail;
+    }
+    QDECREF(options);
+
+    bs->growable = 1;
+    *pbs = bs;
+    return 0;
+
+fail:
+    QDECREF(options);
+    if (!bs->drv) {
+        QDECREF(bs->options);
+    }
+    bdrv_delete(bs);
+    return ret;
+}
+
+/*
+ * Opens the backing file for a BlockDriverState if not yet open
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict is transferred to this
+ * function (even on failure), so if the caller intends to reuse the dictionary,
+ * it needs to use QINCREF() before calling bdrv_file_open.
+ */
+int bdrv_open_backing_file(BlockDriverState *bs, QDict *options)
+{
+    char backing_filename[PATH_MAX];
+    int back_flags, ret;
+    BlockDriver *back_drv = NULL;
+
+    if (bs->backing_hd != NULL) {
+        QDECREF(options);
+        return 0;
+    }
+
+    /* NULL means an empty set of options */
+    if (options == NULL) {
+        options = qdict_new();
+    }
+
+    bs->open_flags &= ~BDRV_O_NO_BACKING;
+    if (qdict_haskey(options, "file.filename")) {
+        backing_filename[0] = '\0';
+    } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) {
+        QDECREF(options);
+        return 0;
+    }
+
+    bs->backing_hd = bdrv_new("");
+    bdrv_get_full_backing_filename(bs, backing_filename,
+                                   sizeof(backing_filename));
+
+    if (bs->backing_format[0] != '\0') {
+        back_drv = bdrv_find_format(bs->backing_format);
+    }
+
+    /* backing files always opened read-only */
+    back_flags = bs->open_flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT);
+
+    ret = bdrv_open(bs->backing_hd,
+                    *backing_filename ? backing_filename : NULL, options,
+                    back_flags, back_drv);
+    if (ret < 0) {
+        bdrv_delete(bs->backing_hd);
+        bs->backing_hd = NULL;
+        bs->open_flags |= BDRV_O_NO_BACKING;
+        return ret;
+    }
+    return 0;
+}
+
+static void extract_subqdict(QDict *src, QDict **dst, const char *start)
+{
+    const QDictEntry *entry, *next;
+    const char *p;
+
+    *dst = qdict_new();
+    entry = qdict_first(src);
+
+    while (entry != NULL) {
+        next = qdict_next(src, entry);
+        if (strstart(entry->key, start, &p)) {
+            qobject_incref(entry->value);
+            qdict_put_obj(*dst, p, entry->value);
+            qdict_del(src, entry->key);
+        }
+        entry = next;
+    }
+}
+
+/*
+ * Opens a disk image (raw, qcow2, vmdk, ...)
+ *
+ * options is a QDict of options to pass to the block drivers, or NULL for an
+ * empty set of options. The reference to the QDict belongs to the block layer
+ * after the call (even on failure), so if the caller intends to reuse the
+ * dictionary, it needs to use QINCREF() before calling bdrv_open.
+ */
+int bdrv_open(BlockDriverState *bs, const char *filename, QDict *options,
+              int flags, BlockDriver *drv)
+{
+    int ret;
+    /* TODO: extra byte is a hack to ensure MAX_PATH space on Windows. */
+    char tmp_filename[PATH_MAX + 1];
+    BlockDriverState *file = NULL;
+    QDict *file_options = NULL;
+
+    /* NULL means an empty set of options */
+    if (options == NULL) {
+        options = qdict_new();
+    }
+
+    bs->options = options;
+    options = qdict_clone_shallow(options);
+
+    /* For snapshot=on, create a temporary qcow2 overlay */
+    if (flags & BDRV_O_SNAPSHOT) {
+        BlockDriverState *bs1;
+        int64_t total_size;
+        BlockDriver *bdrv_qcow2;
+        QEMUOptionParameter *create_options;
+        char backing_filename[PATH_MAX];
+
+        if (qdict_size(options) != 0) {
+            error_report("Can't use snapshot=on with driver-specific options");
+            ret = -EINVAL;
+            goto fail;
+        }
+        assert(filename != NULL);
+
+        /* if snapshot, we create a temporary backing file and open it
+           instead of opening 'filename' directly */
+
+        /* if there is a backing file, use it */
+        bs1 = bdrv_new("");
+        ret = bdrv_open(bs1, filename, NULL, 0, drv);
+        if (ret < 0) {
+            bdrv_delete(bs1);
+            goto fail;
+        }
+        total_size = bdrv_getlength(bs1) & BDRV_SECTOR_MASK;
+
+        bdrv_delete(bs1);
+
+        ret = get_tmp_filename(tmp_filename, sizeof(tmp_filename));
+        if (ret < 0) {
+            goto fail;
+        }
+
+        /* Real path is meaningless for protocols */
+        if (path_has_protocol(filename)) {
+            snprintf(backing_filename, sizeof(backing_filename),
+                     "%s", filename);
+        } else if (!realpath(filename, backing_filename)) {
+            ret = -errno;
+            goto fail;
+        }
+
+        bdrv_qcow2 = bdrv_find_format("qcow2");
+        create_options = parse_option_parameters("", bdrv_qcow2->create_options,
+                                                 NULL);
+
+        set_option_parameter_int(create_options, BLOCK_OPT_SIZE, total_size);
+        set_option_parameter(create_options, BLOCK_OPT_BACKING_FILE,
+                             backing_filename);
+        if (drv) {
+            set_option_parameter(create_options, BLOCK_OPT_BACKING_FMT,
+                drv->format_name);
+        }
+
+        ret = bdrv_create(bdrv_qcow2, tmp_filename, create_options);
+        free_option_parameters(create_options);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        filename = tmp_filename;
+        drv = bdrv_qcow2;
+        bs->is_temporary = 1;
+    }
+
+    /* Open image file without format layer */
+    if (flags & BDRV_O_RDWR) {
+        flags |= BDRV_O_ALLOW_RDWR;
+    }
+
+    extract_subqdict(options, &file_options, "file.");
+
+    ret = bdrv_file_open(&file, filename, file_options,
+                         bdrv_open_flags(bs, flags | BDRV_O_UNMAP));
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Find the right image format driver */
+    if (!drv) {
+        ret = find_image_format(file, filename, &drv);
+    }
+
+    if (!drv) {
+        goto unlink_and_fail;
+    }
+
+    /* Open the image */
+    ret = bdrv_open_common(bs, file, options, flags, drv);
+    if (ret < 0) {
+        goto unlink_and_fail;
+    }
+
+    if (bs->file != file) {
+        bdrv_delete(file);
+        file = NULL;
+    }
+
+    /* If there is a backing file, use it */
+    if ((flags & BDRV_O_NO_BACKING) == 0) {
+        QDict *backing_options;
+
+        extract_subqdict(options, &backing_options, "backing.");
+        ret = bdrv_open_backing_file(bs, backing_options);
+        if (ret < 0) {
+            goto close_and_fail;
+        }
+    }
+
+    /* Check if any unknown options were used */
+    if (qdict_size(options) != 0) {
+        const QDictEntry *entry = qdict_first(options);
+        qerror_report(ERROR_CLASS_GENERIC_ERROR, "Block format '%s' used by "
+            "device '%s' doesn't support the option '%s'",
+            drv->format_name, bs->device_name, entry->key);
+
+        ret = -EINVAL;
+        goto close_and_fail;
+    }
+    QDECREF(options);
+
+    if (!bdrv_key_required(bs)) {
+        bdrv_dev_change_media_cb(bs, true);
+    }
+
+    /* throttling disk I/O limits */
+    if (bs->io_limits_enabled) {
+        bdrv_io_limits_enable(bs);
+    }
+
+    return 0;
+
+unlink_and_fail:
+    if (file != NULL) {
+        bdrv_delete(file);
+    }
+    if (bs->is_temporary) {
+        unlink(filename);
+    }
+fail:
+    QDECREF(bs->options);
+    QDECREF(options);
+    bs->options = NULL;
+    return ret;
+
+close_and_fail:
+    bdrv_close(bs);
+    QDECREF(options);
+    return ret;
+}
+
+typedef struct BlockReopenQueueEntry {
+     bool prepared;
+     BDRVReopenState state;
+     QSIMPLEQ_ENTRY(BlockReopenQueueEntry) entry;
+} BlockReopenQueueEntry;
+
+/*
+ * Adds a BlockDriverState to a simple queue for an atomic, transactional
+ * reopen of multiple devices.
+ *
+ * bs_queue can either be an existing BlockReopenQueue that has had QSIMPLE_INIT
+ * already performed, or alternatively may be NULL a new BlockReopenQueue will
+ * be created and initialized. This newly created BlockReopenQueue should be
+ * passed back in for subsequent calls that are intended to be of the same
+ * atomic 'set'.
+ *
+ * bs is the BlockDriverState to add to the reopen queue.
+ *
+ * flags contains the open flags for the associated bs
+ *
+ * returns a pointer to bs_queue, which is either the newly allocated
+ * bs_queue, or the existing bs_queue being used.
+ *
+ */
+BlockReopenQueue *bdrv_reopen_queue(BlockReopenQueue *bs_queue,
+                                    BlockDriverState *bs, int flags)
+{
+    assert(bs != NULL);
+
+    BlockReopenQueueEntry *bs_entry;
+    if (bs_queue == NULL) {
+        bs_queue = g_new0(BlockReopenQueue, 1);
+        QSIMPLEQ_INIT(bs_queue);
+    }
+
+    if (bs->file) {
+        bdrv_reopen_queue(bs_queue, bs->file, flags);
+    }
+
+    bs_entry = g_new0(BlockReopenQueueEntry, 1);
+    QSIMPLEQ_INSERT_TAIL(bs_queue, bs_entry, entry);
+
+    bs_entry->state.bs = bs;
+    bs_entry->state.flags = flags;
+
+    return bs_queue;
+}
+
+/*
+ * Reopen multiple BlockDriverStates atomically & transactionally.
+ *
+ * The queue passed in (bs_queue) must have been built up previous
+ * via bdrv_reopen_queue().
+ *
+ * Reopens all BDS specified in the queue, with the appropriate
+ * flags.  All devices are prepared for reopen, and failure of any
+ * device will cause all device changes to be abandonded, and intermediate
+ * data cleaned up.
+ *
+ * If all devices prepare successfully, then the changes are committed
+ * to all devices.
+ *
+ */
+int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp)
+{
+    int ret = -1;
+    BlockReopenQueueEntry *bs_entry, *next;
+    Error *local_err = NULL;
+
+    assert(bs_queue != NULL);
+
+    bdrv_drain_all();
+
+    QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
+        if (bdrv_reopen_prepare(&bs_entry->state, bs_queue, &local_err)) {
+            error_propagate(errp, local_err);
+            goto cleanup;
+        }
+        bs_entry->prepared = true;
+    }
+
+    /* If we reach this point, we have success and just need to apply the
+     * changes
+     */
+    QSIMPLEQ_FOREACH(bs_entry, bs_queue, entry) {
+        bdrv_reopen_commit(&bs_entry->state);
+    }
+
+    ret = 0;
+
+cleanup:
+    QSIMPLEQ_FOREACH_SAFE(bs_entry, bs_queue, entry, next) {
+        if (ret && bs_entry->prepared) {
+            bdrv_reopen_abort(&bs_entry->state);
+        }
+        g_free(bs_entry);
+    }
+    g_free(bs_queue);
+    return ret;
+}
+
+
+/* Reopen a single BlockDriverState with the specified flags. */
+int bdrv_reopen(BlockDriverState *bs, int bdrv_flags, Error **errp)
+{
+    int ret = -1;
+    Error *local_err = NULL;
+    BlockReopenQueue *queue = bdrv_reopen_queue(NULL, bs, bdrv_flags);
+
+    ret = bdrv_reopen_multiple(queue, &local_err);
+    if (local_err != NULL) {
+        error_propagate(errp, local_err);
+    }
+    return ret;
+}
+
+
+/*
+ * Prepares a BlockDriverState for reopen. All changes are staged in the
+ * 'opaque' field of the BDRVReopenState, which is used and allocated by
+ * the block driver layer .bdrv_reopen_prepare()
+ *
+ * bs is the BlockDriverState to reopen
+ * flags are the new open flags
+ * queue is the reopen queue
+ *
+ * Returns 0 on success, non-zero on error.  On error errp will be set
+ * as well.
+ *
+ * On failure, bdrv_reopen_abort() will be called to clean up any data.
+ * It is the responsibility of the caller to then call the abort() or
+ * commit() for any other BDS that have been left in a prepare() state
+ *
+ */
+int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue,
+                        Error **errp)
+{
+    int ret = -1;
+    Error *local_err = NULL;
+    BlockDriver *drv;
+
+    assert(reopen_state != NULL);
+    assert(reopen_state->bs->drv != NULL);
+    drv = reopen_state->bs->drv;
+
+    /* if we are to stay read-only, do not allow permission change
+     * to r/w */
+    if (!(reopen_state->bs->open_flags & BDRV_O_ALLOW_RDWR) &&
+        reopen_state->flags & BDRV_O_RDWR) {
+        error_set(errp, QERR_DEVICE_IS_READ_ONLY,
+                  reopen_state->bs->device_name);
+        goto error;
+    }
+
+
+    ret = bdrv_flush(reopen_state->bs);
+    if (ret) {
+        error_set(errp, ERROR_CLASS_GENERIC_ERROR, "Error (%s) flushing drive",
+                  strerror(-ret));
+        goto error;
+    }
+
+    if (drv->bdrv_reopen_prepare) {
+        ret = drv->bdrv_reopen_prepare(reopen_state, queue, &local_err);
+        if (ret) {
+            if (local_err != NULL) {
+                error_propagate(errp, local_err);
+            } else {
+                error_setg(errp, "failed while preparing to reopen image '%s'",
+                           reopen_state->bs->filename);
+            }
+            goto error;
+        }
+    } else {
+        /* It is currently mandatory to have a bdrv_reopen_prepare()
+         * handler for each supported drv. */
+        error_set(errp, QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
+                  drv->format_name, reopen_state->bs->device_name,
+                 "reopening of file");
+        ret = -1;
+        goto error;
+    }
+
+    ret = 0;
+
+error:
+    return ret;
+}
+
+/*
+ * Takes the staged changes for the reopen from bdrv_reopen_prepare(), and
+ * makes them final by swapping the staging BlockDriverState contents into
+ * the active BlockDriverState contents.
+ */
+void bdrv_reopen_commit(BDRVReopenState *reopen_state)
+{
+    BlockDriver *drv;
+
+    assert(reopen_state != NULL);
+    drv = reopen_state->bs->drv;
+    assert(drv != NULL);
+
+    /* If there are any driver level actions to take */
+    if (drv->bdrv_reopen_commit) {
+        drv->bdrv_reopen_commit(reopen_state);
+    }
+
+    /* set BDS specific flags now */
+    reopen_state->bs->open_flags         = reopen_state->flags;
+    reopen_state->bs->enable_write_cache = !!(reopen_state->flags &
+                                              BDRV_O_CACHE_WB);
+    reopen_state->bs->read_only = !(reopen_state->flags & BDRV_O_RDWR);
+}
+
+/*
+ * Abort the reopen, and delete and free the staged changes in
+ * reopen_state
+ */
+void bdrv_reopen_abort(BDRVReopenState *reopen_state)
+{
+    BlockDriver *drv;
+
+    assert(reopen_state != NULL);
+    drv = reopen_state->bs->drv;
+    assert(drv != NULL);
+
+    if (drv->bdrv_reopen_abort) {
+        drv->bdrv_reopen_abort(reopen_state);
+    }
+}
+
+
+void bdrv_close(BlockDriverState *bs)
+{
+    if (bs->job) {
+        block_job_cancel_sync(bs->job);
+    }
+    bdrv_drain_all(); /* complete I/O */
+    bdrv_flush(bs);
+    bdrv_drain_all(); /* in case flush left pending I/O */
+    notifier_list_notify(&bs->close_notifiers, bs);
+
+    if (bs->drv) {
+        if (bs->backing_hd) {
+            bdrv_delete(bs->backing_hd);
+            bs->backing_hd = NULL;
+        }
+        bs->drv->bdrv_close(bs);
+        g_free(bs->opaque);
+#ifdef _WIN32
+        if (bs->is_temporary) {
+            unlink(bs->filename);
+        }
+#endif
+        bs->opaque = NULL;
+        bs->drv = NULL;
+        bs->copy_on_read = 0;
+        bs->backing_file[0] = '\0';
+        bs->backing_format[0] = '\0';
+        bs->total_sectors = 0;
+        bs->encrypted = 0;
+        bs->valid_key = 0;
+        bs->sg = 0;
+        bs->growable = 0;
+        QDECREF(bs->options);
+        bs->options = NULL;
+
+        if (bs->file != NULL) {
+            bdrv_delete(bs->file);
+            bs->file = NULL;
+        }
+    }
+
+    bdrv_dev_change_media_cb(bs, false);
+
+    /*throttling disk I/O limits*/
+    if (bs->io_limits_enabled) {
+        bdrv_io_limits_disable(bs);
+    }
+}
+
+void bdrv_close_all(void)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        bdrv_close(bs);
+    }
+}
+
+/*
+ * Wait for pending requests to complete across all BlockDriverStates
+ *
+ * This function does not flush data to disk, use bdrv_flush_all() for that
+ * after calling this function.
+ *
+ * Note that completion of an asynchronous I/O operation can trigger any
+ * number of other I/O operations on other devices---for example a coroutine
+ * can be arbitrarily complex and a constant flow of I/O can come until the
+ * coroutine is complete.  Because of this, it is not possible to have a
+ * function to drain a single device's I/O queue.
+ */
+void bdrv_drain_all(void)
+{
+    BlockDriverState *bs;
+    bool busy;
+
+    do {
+        busy = qemu_aio_wait();
+
+        /* FIXME: We do not have timer support here, so this is effectively
+         * a busy wait.
+         */
+        QTAILQ_FOREACH(bs, &bdrv_states, list) {
+            if (!qemu_co_queue_empty(&bs->throttled_reqs)) {
+                qemu_co_queue_restart_all(&bs->throttled_reqs);
+                busy = true;
+            }
+        }
+    } while (busy);
+
+    /* If requests are still pending there is a bug somewhere */
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        assert(QLIST_EMPTY(&bs->tracked_requests));
+        assert(qemu_co_queue_empty(&bs->throttled_reqs));
+    }
+}
+
+/* make a BlockDriverState anonymous by removing from bdrv_state list.
+   Also, NULL terminate the device_name to prevent double remove */
+void bdrv_make_anon(BlockDriverState *bs)
+{
+    if (bs->device_name[0] != '\0') {
+        QTAILQ_REMOVE(&bdrv_states, bs, list);
+    }
+    bs->device_name[0] = '\0';
+}
+
+static void bdrv_rebind(BlockDriverState *bs)
+{
+    if (bs->drv && bs->drv->bdrv_rebind) {
+        bs->drv->bdrv_rebind(bs);
+    }
+}
+
+static void bdrv_move_feature_fields(BlockDriverState *bs_dest,
+                                     BlockDriverState *bs_src)
+{
+    /* move some fields that need to stay attached to the device */
+    bs_dest->open_flags         = bs_src->open_flags;
+
+    /* dev info */
+    bs_dest->dev_ops            = bs_src->dev_ops;
+    bs_dest->dev_opaque         = bs_src->dev_opaque;
+    bs_dest->dev                = bs_src->dev;
+    bs_dest->buffer_alignment   = bs_src->buffer_alignment;
+    bs_dest->copy_on_read       = bs_src->copy_on_read;
+
+    bs_dest->enable_write_cache = bs_src->enable_write_cache;
+
+    /* i/o timing parameters */
+    bs_dest->slice_start        = bs_src->slice_start;
+    bs_dest->slice_end          = bs_src->slice_end;
+    bs_dest->slice_submitted    = bs_src->slice_submitted;
+    bs_dest->io_limits          = bs_src->io_limits;
+    bs_dest->throttled_reqs     = bs_src->throttled_reqs;
+    bs_dest->block_timer        = bs_src->block_timer;
+    bs_dest->io_limits_enabled  = bs_src->io_limits_enabled;
+
+    /* r/w error */
+    bs_dest->on_read_error      = bs_src->on_read_error;
+    bs_dest->on_write_error     = bs_src->on_write_error;
+
+    /* i/o status */
+    bs_dest->iostatus_enabled   = bs_src->iostatus_enabled;
+    bs_dest->iostatus           = bs_src->iostatus;
+
+    /* dirty bitmap */
+    bs_dest->dirty_bitmap       = bs_src->dirty_bitmap;
+
+    /* job */
+    bs_dest->in_use             = bs_src->in_use;
+    bs_dest->job                = bs_src->job;
+
+    /* keep the same entry in bdrv_states */
+    pstrcpy(bs_dest->device_name, sizeof(bs_dest->device_name),
+            bs_src->device_name);
+    bs_dest->list = bs_src->list;
+}
+
+/*
+ * Swap bs contents for two image chains while they are live,
+ * while keeping required fields on the BlockDriverState that is
+ * actually attached to a device.
+ *
+ * This will modify the BlockDriverState fields, and swap contents
+ * between bs_new and bs_old. Both bs_new and bs_old are modified.
+ *
+ * bs_new is required to be anonymous.
+ *
+ * This function does not create any image files.
+ */
+void bdrv_swap(BlockDriverState *bs_new, BlockDriverState *bs_old)
+{
+    BlockDriverState tmp;
+
+    /* bs_new must be anonymous and shouldn't have anything fancy enabled */
+    assert(bs_new->device_name[0] == '\0');
+    assert(bs_new->dirty_bitmap == NULL);
+    assert(bs_new->job == NULL);
+    assert(bs_new->dev == NULL);
+    assert(bs_new->in_use == 0);
+    assert(bs_new->io_limits_enabled == false);
+    assert(bs_new->block_timer == NULL);
+
+    tmp = *bs_new;
+    *bs_new = *bs_old;
+    *bs_old = tmp;
+
+    /* there are some fields that should not be swapped, move them back */
+    bdrv_move_feature_fields(&tmp, bs_old);
+    bdrv_move_feature_fields(bs_old, bs_new);
+    bdrv_move_feature_fields(bs_new, &tmp);
+
+    /* bs_new shouldn't be in bdrv_states even after the swap!  */
+    assert(bs_new->device_name[0] == '\0');
+
+    /* Check a few fields that should remain attached to the device */
+    assert(bs_new->dev == NULL);
+    assert(bs_new->job == NULL);
+    assert(bs_new->in_use == 0);
+    assert(bs_new->io_limits_enabled == false);
+    assert(bs_new->block_timer == NULL);
+
+    bdrv_rebind(bs_new);
+    bdrv_rebind(bs_old);
+}
+
+/*
+ * Add new bs contents at the top of an image chain while the chain is
+ * live, while keeping required fields on the top layer.
+ *
+ * This will modify the BlockDriverState fields, and swap contents
+ * between bs_new and bs_top. Both bs_new and bs_top are modified.
+ *
+ * bs_new is required to be anonymous.
+ *
+ * This function does not create any image files.
+ */
+void bdrv_append(BlockDriverState *bs_new, BlockDriverState *bs_top)
+{
+    bdrv_swap(bs_new, bs_top);
+
+    /* The contents of 'tmp' will become bs_top, as we are
+     * swapping bs_new and bs_top contents. */
+    bs_top->backing_hd = bs_new;
+    bs_top->open_flags &= ~BDRV_O_NO_BACKING;
+    pstrcpy(bs_top->backing_file, sizeof(bs_top->backing_file),
+            bs_new->filename);
+    pstrcpy(bs_top->backing_format, sizeof(bs_top->backing_format),
+            bs_new->drv ? bs_new->drv->format_name : "");
+}
+
+void bdrv_delete(BlockDriverState *bs)
+{
+    assert(!bs->dev);
+    assert(!bs->job);
+    assert(!bs->in_use);
+
+    /* remove from list, if necessary */
+    bdrv_make_anon(bs);
+
+    bdrv_close(bs);
+
+    g_free(bs);
+}
+
+int bdrv_attach_dev(BlockDriverState *bs, void *dev)
+/* TODO change to DeviceState *dev when all users are qdevified */
+{
+    if (bs->dev) {
+        return -EBUSY;
+    }
+    bs->dev = dev;
+    bdrv_iostatus_reset(bs);
+    return 0;
+}
+
+/* TODO qdevified devices don't use this, remove when devices are qdevified */
+void bdrv_attach_dev_nofail(BlockDriverState *bs, void *dev)
+{
+    if (bdrv_attach_dev(bs, dev) < 0) {
+        abort();
+    }
+}
+
+void bdrv_detach_dev(BlockDriverState *bs, void *dev)
+/* TODO change to DeviceState *dev when all users are qdevified */
+{
+    assert(bs->dev == dev);
+    bs->dev = NULL;
+    bs->dev_ops = NULL;
+    bs->dev_opaque = NULL;
+    bs->buffer_alignment = 512;
+}
+
+/* TODO change to return DeviceState * when all users are qdevified */
+void *bdrv_get_attached_dev(BlockDriverState *bs)
+{
+    return bs->dev;
+}
+
+void bdrv_set_dev_ops(BlockDriverState *bs, const BlockDevOps *ops,
+                      void *opaque)
+{
+    bs->dev_ops = ops;
+    bs->dev_opaque = opaque;
+}
+
+void bdrv_emit_qmp_error_event(const BlockDriverState *bdrv,
+                               enum MonitorEvent ev,
+                               BlockErrorAction action, bool is_read)
+{
+    QObject *data;
+    const char *action_str;
+
+    switch (action) {
+    case BDRV_ACTION_REPORT:
+        action_str = "report";
+        break;
+    case BDRV_ACTION_IGNORE:
+        action_str = "ignore";
+        break;
+    case BDRV_ACTION_STOP:
+        action_str = "stop";
+        break;
+    default:
+        abort();
+    }
+
+    data = qobject_from_jsonf("{ 'device': %s, 'action': %s, 'operation': %s }",
+                              bdrv->device_name,
+                              action_str,
+                              is_read ? "read" : "write");
+    monitor_protocol_event(ev, data);
+
+    qobject_decref(data);
+}
+
+static void bdrv_emit_qmp_eject_event(BlockDriverState *bs, bool ejected)
+{
+    QObject *data;
+
+    data = qobject_from_jsonf("{ 'device': %s, 'tray-open': %i }",
+                              bdrv_get_device_name(bs), ejected);
+    monitor_protocol_event(QEVENT_DEVICE_TRAY_MOVED, data);
+
+    qobject_decref(data);
+}
+
+static void bdrv_dev_change_media_cb(BlockDriverState *bs, bool load)
+{
+    if (bs->dev_ops && bs->dev_ops->change_media_cb) {
+        bool tray_was_closed = !bdrv_dev_is_tray_open(bs);
+        bs->dev_ops->change_media_cb(bs->dev_opaque, load);
+        if (tray_was_closed) {
+            /* tray open */
+            bdrv_emit_qmp_eject_event(bs, true);
+        }
+        if (load) {
+            /* tray close */
+            bdrv_emit_qmp_eject_event(bs, false);
+        }
+    }
+}
+
+bool bdrv_dev_has_removable_media(BlockDriverState *bs)
+{
+    return !bs->dev || (bs->dev_ops && bs->dev_ops->change_media_cb);
+}
+
+void bdrv_dev_eject_request(BlockDriverState *bs, bool force)
+{
+    if (bs->dev_ops && bs->dev_ops->eject_request_cb) {
+        bs->dev_ops->eject_request_cb(bs->dev_opaque, force);
+    }
+}
+
+bool bdrv_dev_is_tray_open(BlockDriverState *bs)
+{
+    if (bs->dev_ops && bs->dev_ops->is_tray_open) {
+        return bs->dev_ops->is_tray_open(bs->dev_opaque);
+    }
+    return false;
+}
+
+static void bdrv_dev_resize_cb(BlockDriverState *bs)
+{
+    if (bs->dev_ops && bs->dev_ops->resize_cb) {
+        bs->dev_ops->resize_cb(bs->dev_opaque);
+    }
+}
+
+bool bdrv_dev_is_medium_locked(BlockDriverState *bs)
+{
+    if (bs->dev_ops && bs->dev_ops->is_medium_locked) {
+        return bs->dev_ops->is_medium_locked(bs->dev_opaque);
+    }
+    return false;
+}
+
+/*
+ * Run consistency checks on an image
+ *
+ * Returns 0 if the check could be completed (it doesn't mean that the image is
+ * free of errors) or -errno when an internal error occurred. The results of the
+ * check are stored in res.
+ */
+int bdrv_check(BlockDriverState *bs, BdrvCheckResult *res, BdrvCheckMode fix)
+{
+    if (bs->drv->bdrv_check == NULL) {
+        return -ENOTSUP;
+    }
+
+    memset(res, 0, sizeof(*res));
+    return bs->drv->bdrv_check(bs, res, fix);
+}
+
+#define COMMIT_BUF_SECTORS 2048
+
+/* commit COW file into the raw image */
+int bdrv_commit(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    int64_t sector, total_sectors;
+    int n, ro, open_flags;
+    int ret = 0;
+    uint8_t *buf;
+    char filename[PATH_MAX];
+
+    if (!drv)
+        return -ENOMEDIUM;
+    
+    if (!bs->backing_hd) {
+        return -ENOTSUP;
+    }
+
+    if (bdrv_in_use(bs) || bdrv_in_use(bs->backing_hd)) {
+        return -EBUSY;
+    }
+
+    ro = bs->backing_hd->read_only;
+    /* Use pstrcpy (not strncpy): filename must be NUL-terminated. */
+    pstrcpy(filename, sizeof(filename), bs->backing_hd->filename);
+    open_flags =  bs->backing_hd->open_flags;
+
+    if (ro) {
+        if (bdrv_reopen(bs->backing_hd, open_flags | BDRV_O_RDWR, NULL)) {
+            return -EACCES;
+        }
+    }
+
+    total_sectors = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
+    buf = g_malloc(COMMIT_BUF_SECTORS * BDRV_SECTOR_SIZE);
+
+    for (sector = 0; sector < total_sectors; sector += n) {
+        if (bdrv_is_allocated(bs, sector, COMMIT_BUF_SECTORS, &n)) {
+
+            if (bdrv_read(bs, sector, buf, n) != 0) {
+                ret = -EIO;
+                goto ro_cleanup;
+            }
+
+            if (bdrv_write(bs->backing_hd, sector, buf, n) != 0) {
+                ret = -EIO;
+                goto ro_cleanup;
+            }
+        }
+    }
+
+    if (drv->bdrv_make_empty) {
+        ret = drv->bdrv_make_empty(bs);
+        bdrv_flush(bs);
+    }
+
+    /*
+     * Make sure all data we wrote to the backing device is actually
+     * stable on disk.
+     */
+    if (bs->backing_hd)
+        bdrv_flush(bs->backing_hd);
+
+ro_cleanup:
+    g_free(buf);
+
+    if (ro) {
+        /* ignoring error return here */
+        bdrv_reopen(bs->backing_hd, open_flags & ~BDRV_O_RDWR, NULL);
+    }
+
+    return ret;
+}
+
+int bdrv_commit_all(void)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        if (bs->drv && bs->backing_hd) {
+            int ret = bdrv_commit(bs);
+            if (ret < 0) {
+                return ret;
+            }
+        }
+    }
+    return 0;
+}
+
+/**
+ * Remove an active request from the tracked requests list
+ *
+ * This function should be called when a tracked request is completing.
+ */
+static void tracked_request_end(BdrvTrackedRequest *req)
+{
+    QLIST_REMOVE(req, list);
+    qemu_co_queue_restart_all(&req->wait_queue);
+}
+
+/**
+ * Add an active request to the tracked requests list
+ */
+static void tracked_request_begin(BdrvTrackedRequest *req,
+                                  BlockDriverState *bs,
+                                  int64_t sector_num,
+                                  int nb_sectors, bool is_write)
+{
+    *req = (BdrvTrackedRequest){
+        .bs = bs,
+        .sector_num = sector_num,
+        .nb_sectors = nb_sectors,
+        .is_write = is_write,
+        .co = qemu_coroutine_self(),
+    };
+
+    qemu_co_queue_init(&req->wait_queue);
+
+    QLIST_INSERT_HEAD(&bs->tracked_requests, req, list);
+}
+
+/**
+ * Round a region to cluster boundaries
+ */
+void bdrv_round_to_clusters(BlockDriverState *bs,
+                            int64_t sector_num, int nb_sectors,
+                            int64_t *cluster_sector_num,
+                            int *cluster_nb_sectors)
+{
+    BlockDriverInfo bdi;
+
+    if (bdrv_get_info(bs, &bdi) < 0 || bdi.cluster_size == 0) {
+        *cluster_sector_num = sector_num;
+        *cluster_nb_sectors = nb_sectors;
+    } else {
+        int64_t c = bdi.cluster_size / BDRV_SECTOR_SIZE;
+        *cluster_sector_num = QEMU_ALIGN_DOWN(sector_num, c);
+        *cluster_nb_sectors = QEMU_ALIGN_UP(sector_num - *cluster_sector_num +
+                                            nb_sectors, c);
+    }
+}
+
+static bool tracked_request_overlaps(BdrvTrackedRequest *req,
+                                     int64_t sector_num, int nb_sectors) {
+    /*        aaaa   bbbb */
+    if (sector_num >= req->sector_num + req->nb_sectors) {
+        return false;
+    }
+    /* bbbb   aaaa        */
+    if (req->sector_num >= sector_num + nb_sectors) {
+        return false;
+    }
+    return true;
+}
+
+static void coroutine_fn wait_for_overlapping_requests(BlockDriverState *bs,
+        int64_t sector_num, int nb_sectors)
+{
+    BdrvTrackedRequest *req;
+    int64_t cluster_sector_num;
+    int cluster_nb_sectors;
+    bool retry;
+
+    /* If we touch the same cluster it counts as an overlap.  This guarantees
+     * that allocating writes will be serialized and not race with each other
+     * for the same cluster.  For example, in copy-on-read it ensures that the
+     * CoR read and write operations are atomic and guest writes cannot
+     * interleave between them.
+     */
+    bdrv_round_to_clusters(bs, sector_num, nb_sectors,
+                           &cluster_sector_num, &cluster_nb_sectors);
+
+    do {
+        retry = false;
+        QLIST_FOREACH(req, &bs->tracked_requests, list) {
+            if (tracked_request_overlaps(req, cluster_sector_num,
+                                         cluster_nb_sectors)) {
+                /* Hitting this means there was a reentrant request, for
+                 * example, a block driver issuing nested requests.  This must
+                 * never happen since it means deadlock.
+                 */
+                assert(qemu_coroutine_self() != req->co);
+
+                qemu_co_queue_wait(&req->wait_queue);
+                retry = true;
+                break;
+            }
+        }
+    } while (retry);
+}
+
+/*
+ * Return values:
+ * 0        - success
+ * -EINVAL  - backing format specified, but no file
+ * -ENOSPC  - can't update the backing file because no space is left in the
+ *            image file header
+ * -ENOTSUP - format driver doesn't support changing the backing file
+ */
+int bdrv_change_backing_file(BlockDriverState *bs,
+    const char *backing_file, const char *backing_fmt)
+{
+    BlockDriver *drv = bs->drv;
+    int ret;
+
+    /* Backing file format doesn't make sense without a backing file */
+    if (backing_fmt && !backing_file) {
+        return -EINVAL;
+    }
+
+    if (drv->bdrv_change_backing_file != NULL) {
+        ret = drv->bdrv_change_backing_file(bs, backing_file, backing_fmt);
+    } else {
+        ret = -ENOTSUP;
+    }
+
+    if (ret == 0) {
+        pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: "");
+        pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: "");
+    }
+    return ret;
+}
+
+/*
+ * Finds the image layer in the chain that has 'bs' as its backing file.
+ *
+ * active is the current topmost image.
+ *
+ * Returns NULL if bs is not found in active's image chain,
+ * or if active == bs.
+ */
+BlockDriverState *bdrv_find_overlay(BlockDriverState *active,
+                                    BlockDriverState *bs)
+{
+    BlockDriverState *overlay = NULL;
+    BlockDriverState *intermediate;
+
+    assert(active != NULL);
+    assert(bs != NULL);
+
+    /* if bs is the same as active, then by definition it has no overlay
+     */
+    if (active == bs) {
+        return NULL;
+    }
+
+    intermediate = active;
+    while (intermediate->backing_hd) {
+        if (intermediate->backing_hd == bs) {
+            overlay = intermediate;
+            break;
+        }
+        intermediate = intermediate->backing_hd;
+    }
+
+    return overlay;
+}
+
+typedef struct BlkIntermediateStates {
+    BlockDriverState *bs;
+    QSIMPLEQ_ENTRY(BlkIntermediateStates) entry;
+} BlkIntermediateStates;
+
+
+/*
+ * Drops images above 'base' up to and including 'top', and sets the image
+ * above 'top' to have base as its backing file.
+ *
+ * Requires that the overlay to 'top' is opened r/w, so that the backing file
+ * information in 'bs' can be properly updated.
+ *
+ * E.g., this will convert the following chain:
+ * bottom <- base <- intermediate <- top <- active
+ *
+ * to
+ *
+ * bottom <- base <- active
+ *
+ * It is allowed for bottom==base, in which case it converts:
+ *
+ * base <- intermediate <- top <- active
+ *
+ * to
+ *
+ * base <- active
+ *
+ * Error conditions:
+ *  if active == top, that is considered an error
+ *
+ */
+int bdrv_drop_intermediate(BlockDriverState *active, BlockDriverState *top,
+                           BlockDriverState *base)
+{
+    BlockDriverState *intermediate;
+    BlockDriverState *base_bs = NULL;
+    BlockDriverState *new_top_bs = NULL;
+    BlkIntermediateStates *intermediate_state, *next;
+    int ret = -EIO;
+
+    QSIMPLEQ_HEAD(states_to_delete, BlkIntermediateStates) states_to_delete;
+    QSIMPLEQ_INIT(&states_to_delete);
+
+    if (!top->drv || !base->drv) {
+        goto exit;
+    }
+
+    new_top_bs = bdrv_find_overlay(active, top);
+
+    if (new_top_bs == NULL) {
+        /* we could not find the image above 'top', this is an error */
+        goto exit;
+    }
+
+    /* special case of new_top_bs->backing_hd already pointing to base - nothing
+     * to do, no intermediate images */
+    if (new_top_bs->backing_hd == base) {
+        ret = 0;
+        goto exit;
+    }
+
+    intermediate = top;
+
+    /* now we will go down through the list, and add each BDS we find
+     * into our deletion queue, until we hit the 'base'
+     */
+    while (intermediate) {
+        intermediate_state = g_malloc0(sizeof(BlkIntermediateStates));
+        intermediate_state->bs = intermediate;
+        QSIMPLEQ_INSERT_TAIL(&states_to_delete, intermediate_state, entry);
+
+        if (intermediate->backing_hd == base) {
+            base_bs = intermediate->backing_hd;
+            break;
+        }
+        intermediate = intermediate->backing_hd;
+    }
+    if (base_bs == NULL) {
+        /* something went wrong, we did not end at the base. safely
+         * unravel everything, and exit with error */
+        goto exit;
+    }
+
+    /* success - we can delete the intermediate states, and link top->base */
+    ret = bdrv_change_backing_file(new_top_bs, base_bs->filename,
+                                   base_bs->drv ? base_bs->drv->format_name : "");
+    if (ret) {
+        goto exit;
+    }
+    new_top_bs->backing_hd = base_bs;
+
+
+    QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
+        /* so that bdrv_close() does not recursively close the chain */
+        intermediate_state->bs->backing_hd = NULL;
+        bdrv_delete(intermediate_state->bs);
+    }
+    ret = 0;
+
+exit:
+    QSIMPLEQ_FOREACH_SAFE(intermediate_state, &states_to_delete, entry, next) {
+        g_free(intermediate_state);
+    }
+    return ret;
+}
+
+
+static int bdrv_check_byte_request(BlockDriverState *bs, int64_t offset,
+                                   size_t size)
+{
+    int64_t len;
+
+    if (!bdrv_is_inserted(bs))
+        return -ENOMEDIUM;
+
+    if (bs->growable)
+        return 0;
+
+    len = bdrv_getlength(bs);
+
+    if (offset < 0)
+        return -EIO;
+
+    if ((offset > len) || (len - offset < size))
+        return -EIO;
+
+    return 0;
+}
+
+static int bdrv_check_request(BlockDriverState *bs, int64_t sector_num,
+                              int nb_sectors)
+{
+    return bdrv_check_byte_request(bs, sector_num * BDRV_SECTOR_SIZE,
+                                   nb_sectors * BDRV_SECTOR_SIZE);
+}
+
+typedef struct RwCo {
+    BlockDriverState *bs;
+    int64_t sector_num;
+    int nb_sectors;
+    QEMUIOVector *qiov;
+    bool is_write;
+    int ret;
+} RwCo;
+
+static void coroutine_fn bdrv_rw_co_entry(void *opaque)
+{
+    RwCo *rwco = opaque;
+
+    if (!rwco->is_write) {
+        rwco->ret = bdrv_co_do_readv(rwco->bs, rwco->sector_num,
+                                     rwco->nb_sectors, rwco->qiov, 0);
+    } else {
+        rwco->ret = bdrv_co_do_writev(rwco->bs, rwco->sector_num,
+                                      rwco->nb_sectors, rwco->qiov, 0);
+    }
+}
+
+/*
+ * Process a vectored synchronous request using coroutines
+ */
+static int bdrv_rwv_co(BlockDriverState *bs, int64_t sector_num,
+                       QEMUIOVector *qiov, bool is_write)
+{
+    Coroutine *co;
+    RwCo rwco = {
+        .bs = bs,
+        .sector_num = sector_num,
+        .nb_sectors = qiov->size >> BDRV_SECTOR_BITS,
+        .qiov = qiov,
+        .is_write = is_write,
+        .ret = NOT_DONE,
+    };
+    assert((qiov->size & (BDRV_SECTOR_SIZE - 1)) == 0);
+
+    /**
+     * In sync call context, when the vcpu is blocked, this throttling timer
+     * will not fire; so the I/O throttling function has to be disabled here
+     * if it has been enabled.
+     */
+    if (bs->io_limits_enabled) {
+        fprintf(stderr, "Disabling I/O throttling on '%s' due "
+                        "to synchronous I/O.\n", bdrv_get_device_name(bs));
+        bdrv_io_limits_disable(bs);
+    }
+
+    if (qemu_in_coroutine()) {
+        /* Fast-path if already in coroutine context */
+        bdrv_rw_co_entry(&rwco);
+    } else {
+        co = qemu_coroutine_create(bdrv_rw_co_entry);
+        qemu_coroutine_enter(co, &rwco);
+        while (rwco.ret == NOT_DONE) {
+            qemu_aio_wait();
+        }
+    }
+    return rwco.ret;
+}
+
+/*
+ * Process a synchronous request using coroutines
+ */
+static int bdrv_rw_co(BlockDriverState *bs, int64_t sector_num, uint8_t *buf,
+                      int nb_sectors, bool is_write)
+{
+    QEMUIOVector qiov;
+    struct iovec iov = {
+        .iov_base = (void *)buf,
+        .iov_len = nb_sectors * BDRV_SECTOR_SIZE,
+    };
+
+    qemu_iovec_init_external(&qiov, &iov, 1);
+    return bdrv_rwv_co(bs, sector_num, &qiov, is_write);
+}
+
+/* return < 0 if error. See bdrv_write() for the return codes */
+int bdrv_read(BlockDriverState *bs, int64_t sector_num,
+              uint8_t *buf, int nb_sectors)
+{
+    return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false);
+}
+
+/* Just like bdrv_read(), but with I/O throttling temporarily disabled */
+int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num,
+                          uint8_t *buf, int nb_sectors)
+{
+    bool enabled;
+    int ret;
+
+    enabled = bs->io_limits_enabled;
+    bs->io_limits_enabled = false;
+    ret = bdrv_read(bs, 0, buf, 1);
+    bs->io_limits_enabled = enabled;
+    return ret;
+}
+
+/* Return < 0 if error. Important errors are:
+  -EIO         generic I/O error (may happen for all errors)
+  -ENOMEDIUM   No media inserted.
+  -EINVAL      Invalid sector number or nb_sectors
+  -EACCES      Trying to write a read-only device
+*/
+int bdrv_write(BlockDriverState *bs, int64_t sector_num,
+               const uint8_t *buf, int nb_sectors)
+{
+    return bdrv_rw_co(bs, sector_num, (uint8_t *)buf, nb_sectors, true);
+}
+
+int bdrv_writev(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov)
+{
+    return bdrv_rwv_co(bs, sector_num, qiov, true);
+}
+
+int bdrv_pread(BlockDriverState *bs, int64_t offset,
+               void *buf, int count1)
+{
+    uint8_t tmp_buf[BDRV_SECTOR_SIZE];
+    int len, nb_sectors, count;
+    int64_t sector_num;
+    int ret;
+
+    count = count1;
+    /* first read to align to sector start */
+    len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
+    if (len > count)
+        len = count;
+    sector_num = offset >> BDRV_SECTOR_BITS;
+    if (len > 0) {
+        if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+        memcpy(buf, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)), len);
+        count -= len;
+        if (count == 0)
+            return count1;
+        sector_num++;
+        buf += len;
+    }
+
+    /* read the sectors "in place" */
+    nb_sectors = count >> BDRV_SECTOR_BITS;
+    if (nb_sectors > 0) {
+        if ((ret = bdrv_read(bs, sector_num, buf, nb_sectors)) < 0)
+            return ret;
+        sector_num += nb_sectors;
+        len = nb_sectors << BDRV_SECTOR_BITS;
+        buf += len;
+        count -= len;
+    }
+
+    /* add data from the last sector */
+    if (count > 0) {
+        if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+        memcpy(buf, tmp_buf, count);
+    }
+    return count1;
+}
+
+int bdrv_pwritev(BlockDriverState *bs, int64_t offset, QEMUIOVector *qiov)
+{
+    uint8_t tmp_buf[BDRV_SECTOR_SIZE];
+    int len, nb_sectors, count;
+    int64_t sector_num;
+    int ret;
+
+    count = qiov->size;
+
+    /* first write to align to sector start */
+    len = (BDRV_SECTOR_SIZE - offset) & (BDRV_SECTOR_SIZE - 1);
+    if (len > count)
+        len = count;
+    sector_num = offset >> BDRV_SECTOR_BITS;
+    if (len > 0) {
+        if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+        qemu_iovec_to_buf(qiov, 0, tmp_buf + (offset & (BDRV_SECTOR_SIZE - 1)),
+                          len);
+        if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+        count -= len;
+        if (count == 0)
+            return qiov->size;
+        sector_num++;
+    }
+
+    /* write the sectors "in place" */
+    nb_sectors = count >> BDRV_SECTOR_BITS;
+    if (nb_sectors > 0) {
+        QEMUIOVector qiov_inplace;
+
+        qemu_iovec_init(&qiov_inplace, qiov->niov);
+        qemu_iovec_concat(&qiov_inplace, qiov, len,
+                          nb_sectors << BDRV_SECTOR_BITS);
+        ret = bdrv_writev(bs, sector_num, &qiov_inplace);
+        qemu_iovec_destroy(&qiov_inplace);
+        if (ret < 0) {
+            return ret;
+        }
+
+        sector_num += nb_sectors;
+        len = nb_sectors << BDRV_SECTOR_BITS;
+        count -= len;
+    }
+
+    /* add data from the last sector */
+    if (count > 0) {
+        if ((ret = bdrv_read(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+        qemu_iovec_to_buf(qiov, qiov->size - count, tmp_buf, count);
+        if ((ret = bdrv_write(bs, sector_num, tmp_buf, 1)) < 0)
+            return ret;
+    }
+    return qiov->size;
+}
+
+int bdrv_pwrite(BlockDriverState *bs, int64_t offset,
+                const void *buf, int count1)
+{
+    QEMUIOVector qiov;
+    struct iovec iov = {
+        .iov_base   = (void *) buf,
+        .iov_len    = count1,
+    };
+
+    qemu_iovec_init_external(&qiov, &iov, 1);
+    return bdrv_pwritev(bs, offset, &qiov);
+}
+
+/*
+ * Writes to the file and ensures that no writes are reordered across this
+ * request (acts as a barrier)
+ *
+ * Returns 0 on success, -errno in error cases.
+ */
+int bdrv_pwrite_sync(BlockDriverState *bs, int64_t offset,
+    const void *buf, int count)
+{
+    int ret;
+
+    ret = bdrv_pwrite(bs, offset, buf, count);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* No flush needed for cache modes that already do it */
+    if (bs->enable_write_cache) {
+        bdrv_flush(bs);
+    }
+
+    return 0;
+}
+
+static int coroutine_fn bdrv_co_do_copy_on_readv(BlockDriverState *bs,
+        int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
+{
+    /* Perform I/O through a temporary buffer so that users who scribble over
+     * their read buffer while the operation is in progress do not end up
+     * modifying the image file.  This is critical for zero-copy guest I/O
+     * where anything might happen inside guest memory.
+     */
+    void *bounce_buffer;
+
+    BlockDriver *drv = bs->drv;
+    struct iovec iov;
+    QEMUIOVector bounce_qiov;
+    int64_t cluster_sector_num;
+    int cluster_nb_sectors;
+    size_t skip_bytes;
+    int ret;
+
+    /* Cover entire cluster so no additional backing file I/O is required when
+     * allocating cluster in the image file.
+     */
+    bdrv_round_to_clusters(bs, sector_num, nb_sectors,
+                           &cluster_sector_num, &cluster_nb_sectors);
+
+    trace_bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors,
+                                   cluster_sector_num, cluster_nb_sectors);
+
+    iov.iov_len = cluster_nb_sectors * BDRV_SECTOR_SIZE;
+    iov.iov_base = bounce_buffer = qemu_blockalign(bs, iov.iov_len);
+    qemu_iovec_init_external(&bounce_qiov, &iov, 1);
+
+    ret = drv->bdrv_co_readv(bs, cluster_sector_num, cluster_nb_sectors,
+                             &bounce_qiov);
+    if (ret < 0) {
+        goto err;
+    }
+
+    if (drv->bdrv_co_write_zeroes &&
+        buffer_is_zero(bounce_buffer, iov.iov_len)) {
+        ret = bdrv_co_do_write_zeroes(bs, cluster_sector_num,
+                                      cluster_nb_sectors);
+    } else {
+        /* This does not change the data on the disk, it is not necessary
+         * to flush even in cache=writethrough mode.
+         */
+        ret = drv->bdrv_co_writev(bs, cluster_sector_num, cluster_nb_sectors,
+                                  &bounce_qiov);
+    }
+
+    if (ret < 0) {
+        /* It might be okay to ignore write errors for guest requests.  If this
+         * is a deliberate copy-on-read then we don't want to ignore the error.
+         * Simply report it in all cases.
+         */
+        goto err;
+    }
+
+    skip_bytes = (sector_num - cluster_sector_num) * BDRV_SECTOR_SIZE;
+    qemu_iovec_from_buf(qiov, 0, bounce_buffer + skip_bytes,
+                        nb_sectors * BDRV_SECTOR_SIZE);
+
+err:
+    qemu_vfree(bounce_buffer);
+    return ret;
+}
+
+/*
+ * Handle a read request in coroutine context
+ */
+static int coroutine_fn bdrv_co_do_readv(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
+    BdrvRequestFlags flags)
+{
+    BlockDriver *drv = bs->drv;
+    BdrvTrackedRequest req;
+    int ret;
+
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (bdrv_check_request(bs, sector_num, nb_sectors)) {
+        return -EIO;
+    }
+
+    /* throttling disk read I/O */
+    if (bs->io_limits_enabled) {
+        bdrv_io_limits_intercept(bs, false, nb_sectors);
+    }
+
+    if (bs->copy_on_read) {
+        flags |= BDRV_REQ_COPY_ON_READ;
+    }
+    if (flags & BDRV_REQ_COPY_ON_READ) {
+        bs->copy_on_read_in_flight++;
+    }
+
+    if (bs->copy_on_read_in_flight) {
+        wait_for_overlapping_requests(bs, sector_num, nb_sectors);
+    }
+
+    tracked_request_begin(&req, bs, sector_num, nb_sectors, false);
+
+    if (flags & BDRV_REQ_COPY_ON_READ) {
+        int pnum;
+
+        ret = bdrv_co_is_allocated(bs, sector_num, nb_sectors, &pnum);
+        if (ret < 0) {
+            goto out;
+        }
+
+        if (!ret || pnum != nb_sectors) {
+            ret = bdrv_co_do_copy_on_readv(bs, sector_num, nb_sectors, qiov);
+            goto out;
+        }
+    }
+
+    ret = drv->bdrv_co_readv(bs, sector_num, nb_sectors, qiov);
+
+out:
+    tracked_request_end(&req);
+
+    if (flags & BDRV_REQ_COPY_ON_READ) {
+        bs->copy_on_read_in_flight--;
+    }
+
+    return ret;
+}
+
+int coroutine_fn bdrv_co_readv(BlockDriverState *bs, int64_t sector_num,
+    int nb_sectors, QEMUIOVector *qiov)
+{
+    trace_bdrv_co_readv(bs, sector_num, nb_sectors);
+
+    return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov, 0);
+}
+
+int coroutine_fn bdrv_co_copy_on_readv(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov)
+{
+    trace_bdrv_co_copy_on_readv(bs, sector_num, nb_sectors);
+
+    return bdrv_co_do_readv(bs, sector_num, nb_sectors, qiov,
+                            BDRV_REQ_COPY_ON_READ);
+}
+
+static int coroutine_fn bdrv_co_do_write_zeroes(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors)
+{
+    BlockDriver *drv = bs->drv;
+    QEMUIOVector qiov;
+    struct iovec iov;
+    int ret;
+
+    /* TODO Emulate only part of misaligned requests instead of letting block
+     * drivers return -ENOTSUP and emulate everything */
+
+    /* First try the efficient write zeroes operation */
+    if (drv->bdrv_co_write_zeroes) {
+        ret = drv->bdrv_co_write_zeroes(bs, sector_num, nb_sectors);
+        if (ret != -ENOTSUP) {
+            return ret;
+        }
+    }
+
+    /* Fall back to bounce buffer if write zeroes is unsupported */
+    iov.iov_len  = nb_sectors * BDRV_SECTOR_SIZE;
+    iov.iov_base = qemu_blockalign(bs, iov.iov_len);
+    memset(iov.iov_base, 0, iov.iov_len);
+    qemu_iovec_init_external(&qiov, &iov, 1);
+
+    ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, &qiov);
+
+    qemu_vfree(iov.iov_base);
+    return ret;
+}
+
+/*
+ * Handle a write request in coroutine context
+ */
+static int coroutine_fn bdrv_co_do_writev(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors, QEMUIOVector *qiov,
+    BdrvRequestFlags flags)
+{
+    BlockDriver *drv = bs->drv;
+    BdrvTrackedRequest req;
+    int ret;
+
+    if (!bs->drv) {
+        return -ENOMEDIUM;
+    }
+    if (bs->read_only) {
+        return -EACCES;
+    }
+    if (bdrv_check_request(bs, sector_num, nb_sectors)) {
+        return -EIO;
+    }
+
+    /* throttling disk write I/O */
+    if (bs->io_limits_enabled) {
+        bdrv_io_limits_intercept(bs, true, nb_sectors);
+    }
+
+    if (bs->copy_on_read_in_flight) {
+        wait_for_overlapping_requests(bs, sector_num, nb_sectors);
+    }
+
+    tracked_request_begin(&req, bs, sector_num, nb_sectors, true);
+
+    ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req);
+
+    if (ret < 0) {
+        /* Do nothing, write notifier decided to fail this request */
+    } else if (flags & BDRV_REQ_ZERO_WRITE) {
+        ret = bdrv_co_do_write_zeroes(bs, sector_num, nb_sectors);
+    } else {
+        ret = drv->bdrv_co_writev(bs, sector_num, nb_sectors, qiov);
+    }
+
+    if (ret == 0 && !bs->enable_write_cache) {
+        ret = bdrv_co_flush(bs);
+    }
+
+    if (bs->dirty_bitmap) {
+        bdrv_set_dirty(bs, sector_num, nb_sectors);
+    }
+
+    if (bs->wr_highest_sector < sector_num + nb_sectors - 1) {
+        bs->wr_highest_sector = sector_num + nb_sectors - 1;
+    }
+
+    tracked_request_end(&req);
+
+    return ret;
+}
+
+int coroutine_fn bdrv_co_writev(BlockDriverState *bs, int64_t sector_num,
+    int nb_sectors, QEMUIOVector *qiov)
+{
+    trace_bdrv_co_writev(bs, sector_num, nb_sectors);
+
+    return bdrv_co_do_writev(bs, sector_num, nb_sectors, qiov, 0);
+}
+
+int coroutine_fn bdrv_co_write_zeroes(BlockDriverState *bs,
+                                      int64_t sector_num, int nb_sectors)
+{
+    trace_bdrv_co_write_zeroes(bs, sector_num, nb_sectors);
+
+    return bdrv_co_do_writev(bs, sector_num, nb_sectors, NULL,
+                             BDRV_REQ_ZERO_WRITE);
+}
+
+/**
+ * Truncate file to 'offset' bytes (needed only for file protocols)
+ */
+int bdrv_truncate(BlockDriverState *bs, int64_t offset)
+{
+    BlockDriver *drv = bs->drv;
+    int ret;
+    if (!drv)
+        return -ENOMEDIUM;
+    if (!drv->bdrv_truncate)
+        return -ENOTSUP;
+    if (bs->read_only)
+        return -EACCES;
+    if (bdrv_in_use(bs))
+        return -EBUSY;
+    ret = drv->bdrv_truncate(bs, offset);
+    if (ret == 0) {
+        ret = refresh_total_sectors(bs, offset >> BDRV_SECTOR_BITS);
+        bdrv_dev_resize_cb(bs);
+    }
+    return ret;
+}
+
+/**
+ * Length of a allocated file in bytes. Sparse files are counted by actual
+ * allocated space. Return < 0 if error or unknown.
+ */
+int64_t bdrv_get_allocated_file_size(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_get_allocated_file_size) {
+        return drv->bdrv_get_allocated_file_size(bs);
+    }
+    if (bs->file) {
+        return bdrv_get_allocated_file_size(bs->file);
+    }
+    return -ENOTSUP;
+}
+
+/**
+ * Length of a file in bytes. Return < 0 if error or unknown.
+ */
+int64_t bdrv_getlength(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv)
+        return -ENOMEDIUM;
+
+    if (bs->growable || bdrv_dev_has_removable_media(bs)) {
+        if (drv->bdrv_getlength) {
+            return drv->bdrv_getlength(bs);
+        }
+    }
+    return bs->total_sectors * BDRV_SECTOR_SIZE;
+}
+
+/* return 0 as number of sectors if no device present or error */
+void bdrv_get_geometry(BlockDriverState *bs, uint64_t *nb_sectors_ptr)
+{
+    int64_t length;
+    length = bdrv_getlength(bs);
+    if (length < 0)
+        length = 0;
+    else
+        length = length >> BDRV_SECTOR_BITS;
+    *nb_sectors_ptr = length;
+}
+
+/* throttling disk io limits */
+void bdrv_set_io_limits(BlockDriverState *bs,
+                        BlockIOLimit *io_limits)
+{
+    bs->io_limits = *io_limits;
+    bs->io_limits_enabled = bdrv_io_limits_enabled(bs);
+}
+
+void bdrv_set_on_error(BlockDriverState *bs, BlockdevOnError on_read_error,
+                       BlockdevOnError on_write_error)
+{
+    bs->on_read_error = on_read_error;
+    bs->on_write_error = on_write_error;
+}
+
+BlockdevOnError bdrv_get_on_error(BlockDriverState *bs, bool is_read)
+{
+    return is_read ? bs->on_read_error : bs->on_write_error;
+}
+
+BlockErrorAction bdrv_get_error_action(BlockDriverState *bs, bool is_read, int error)
+{
+    BlockdevOnError on_err = is_read ? bs->on_read_error : bs->on_write_error;
+
+    switch (on_err) {
+    case BLOCKDEV_ON_ERROR_ENOSPC:
+        return (error == ENOSPC) ? BDRV_ACTION_STOP : BDRV_ACTION_REPORT;
+    case BLOCKDEV_ON_ERROR_STOP:
+        return BDRV_ACTION_STOP;
+    case BLOCKDEV_ON_ERROR_REPORT:
+        return BDRV_ACTION_REPORT;
+    case BLOCKDEV_ON_ERROR_IGNORE:
+        return BDRV_ACTION_IGNORE;
+    default:
+        abort();
+    }
+}
+
+/* This is done by device models because, while the block layer knows
+ * about the error, it does not know whether an operation comes from
+ * the device or the block layer (from a job, for example).
+ */
+void bdrv_error_action(BlockDriverState *bs, BlockErrorAction action,
+                       bool is_read, int error)
+{
+    assert(error >= 0);
+    bdrv_emit_qmp_error_event(bs, QEVENT_BLOCK_IO_ERROR, action, is_read);
+    if (action == BDRV_ACTION_STOP) {
+        vm_stop(RUN_STATE_IO_ERROR);
+        bdrv_iostatus_set_err(bs, error);
+    }
+}
+
+int bdrv_is_read_only(BlockDriverState *bs)
+{
+    return bs->read_only;
+}
+
+int bdrv_is_sg(BlockDriverState *bs)
+{
+    return bs->sg;
+}
+
+int bdrv_enable_write_cache(BlockDriverState *bs)
+{
+    return bs->enable_write_cache;
+}
+
+void bdrv_set_enable_write_cache(BlockDriverState *bs, bool wce)
+{
+    bs->enable_write_cache = wce;
+
+    /* so a reopen() will preserve wce */
+    if (wce) {
+        bs->open_flags |= BDRV_O_CACHE_WB;
+    } else {
+        bs->open_flags &= ~BDRV_O_CACHE_WB;
+    }
+}
+
+int bdrv_is_encrypted(BlockDriverState *bs)
+{
+    if (bs->backing_hd && bs->backing_hd->encrypted)
+        return 1;
+    return bs->encrypted;
+}
+
+int bdrv_key_required(BlockDriverState *bs)
+{
+    BlockDriverState *backing_hd = bs->backing_hd;
+
+    if (backing_hd && backing_hd->encrypted && !backing_hd->valid_key)
+        return 1;
+    return (bs->encrypted && !bs->valid_key);
+}
+
+int bdrv_set_key(BlockDriverState *bs, const char *key)
+{
+    int ret;
+    if (bs->backing_hd && bs->backing_hd->encrypted) {
+        ret = bdrv_set_key(bs->backing_hd, key);
+        if (ret < 0)
+            return ret;
+        if (!bs->encrypted)
+            return 0;
+    }
+    if (!bs->encrypted) {
+        return -EINVAL;
+    } else if (!bs->drv || !bs->drv->bdrv_set_key) {
+        return -ENOMEDIUM;
+    }
+    ret = bs->drv->bdrv_set_key(bs, key);
+    if (ret < 0) {
+        bs->valid_key = 0;
+    } else if (!bs->valid_key) {
+        bs->valid_key = 1;
+        /* call the change callback now, we skipped it on open */
+        bdrv_dev_change_media_cb(bs, true);
+    }
+    return ret;
+}
+
+const char *bdrv_get_format_name(BlockDriverState *bs)
+{
+    return bs->drv ? bs->drv->format_name : NULL;
+}
+
+void bdrv_iterate_format(void (*it)(void *opaque, const char *name),
+                         void *opaque)
+{
+    BlockDriver *drv;
+
+    QLIST_FOREACH(drv, &bdrv_drivers, list) {
+        it(opaque, drv->format_name);
+    }
+}
+
+BlockDriverState *bdrv_find(const char *name)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        if (!strcmp(name, bs->device_name)) {
+            return bs;
+        }
+    }
+    return NULL;
+}
+
+BlockDriverState *bdrv_next(BlockDriverState *bs)
+{
+    if (!bs) {
+        return QTAILQ_FIRST(&bdrv_states);
+    }
+    return QTAILQ_NEXT(bs, list);
+}
+
+void bdrv_iterate(void (*it)(void *opaque, BlockDriverState *bs), void *opaque)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        it(opaque, bs);
+    }
+}
+
+const char *bdrv_get_device_name(BlockDriverState *bs)
+{
+    return bs->device_name;
+}
+
+int bdrv_get_flags(BlockDriverState *bs)
+{
+    return bs->open_flags;
+}
+
+int bdrv_flush_all(void)
+{
+    BlockDriverState *bs;
+    int result = 0;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        int ret = bdrv_flush(bs);
+        if (ret < 0 && !result) {
+            result = ret;
+        }
+    }
+
+    return result;
+}
+
+int bdrv_has_zero_init_1(BlockDriverState *bs)
+{
+    return 1;
+}
+
+int bdrv_has_zero_init(BlockDriverState *bs)
+{
+    assert(bs->drv);
+
+    if (bs->drv->bdrv_has_zero_init) {
+        return bs->drv->bdrv_has_zero_init(bs);
+    }
+
+    /* safe default */
+    return 0;
+}
+
+typedef struct BdrvCoIsAllocatedData {
+    BlockDriverState *bs;
+    BlockDriverState *base;
+    int64_t sector_num;
+    int nb_sectors;
+    int *pnum;
+    int ret;
+    bool done;
+} BdrvCoIsAllocatedData;
+
+/*
+ * Returns true iff the specified sector is present in the disk image. Drivers
+ * not implementing the functionality are assumed to not support backing files,
+ * hence all their sectors are reported as allocated.
+ *
+ * If 'sector_num' is beyond the end of the disk image the return value is 0
+ * and 'pnum' is set to 0.
+ *
+ * 'pnum' is set to the number of sectors (including and immediately following
+ * the specified sector) that are known to be in the same
+ * allocated/unallocated state.
+ *
+ * 'nb_sectors' is the max value 'pnum' should be set to.  If nb_sectors goes
+ * beyond the end of the disk image it will be clamped.
+ */
+int coroutine_fn bdrv_co_is_allocated(BlockDriverState *bs, int64_t sector_num,
+                                      int nb_sectors, int *pnum)
+{
+    int64_t n;
+
+    if (sector_num >= bs->total_sectors) {
+        *pnum = 0;
+        return 0;
+    }
+
+    n = bs->total_sectors - sector_num;
+    if (n < nb_sectors) {
+        nb_sectors = n;
+    }
+
+    if (!bs->drv->bdrv_co_is_allocated) {
+        *pnum = nb_sectors;
+        return 1;
+    }
+
+    return bs->drv->bdrv_co_is_allocated(bs, sector_num, nb_sectors, pnum);
+}
+
+/* Coroutine wrapper for bdrv_is_allocated() */
+static void coroutine_fn bdrv_is_allocated_co_entry(void *opaque)
+{
+    BdrvCoIsAllocatedData *data = opaque;
+    BlockDriverState *bs = data->bs;
+
+    data->ret = bdrv_co_is_allocated(bs, data->sector_num, data->nb_sectors,
+                                     data->pnum);
+    data->done = true;
+}
+
+/*
+ * Synchronous wrapper around bdrv_co_is_allocated().
+ *
+ * See bdrv_co_is_allocated() for details.
+ */
+int bdrv_is_allocated(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
+                      int *pnum)
+{
+    Coroutine *co;
+    BdrvCoIsAllocatedData data = {
+        .bs = bs,
+        .sector_num = sector_num,
+        .nb_sectors = nb_sectors,
+        .pnum = pnum,
+        .done = false,
+    };
+
+    co = qemu_coroutine_create(bdrv_is_allocated_co_entry);
+    qemu_coroutine_enter(co, &data);
+    while (!data.done) {
+        qemu_aio_wait();
+    }
+    return data.ret;
+}
+
+/*
+ * Given an image chain: ... -> [BASE] -> [INTER1] -> [INTER2] -> [TOP]
+ *
+ * Return true if the given sector is allocated in any image between
+ * BASE and TOP (inclusive).  BASE can be NULL to check if the given
+ * sector is allocated in any image of the chain.  Return false otherwise.
+ *
+ * 'pnum' is set to the number of sectors (including and immediately following
+ *  the specified sector) that are known to be in the same
+ *  allocated/unallocated state.
+ *
+ */
+int coroutine_fn bdrv_co_is_allocated_above(BlockDriverState *top,
+                                            BlockDriverState *base,
+                                            int64_t sector_num,
+                                            int nb_sectors, int *pnum)
+{
+    BlockDriverState *intermediate;
+    int ret, n = nb_sectors;
+
+    intermediate = top;
+    while (intermediate && intermediate != base) {
+        int pnum_inter;
+        ret = bdrv_co_is_allocated(intermediate, sector_num, nb_sectors,
+                                   &pnum_inter);
+        if (ret < 0) {
+            return ret;
+        } else if (ret) {
+            *pnum = pnum_inter;
+            return 1;
+        }
+
+        /*
+         * [sector_num, nb_sectors] is unallocated on top but intermediate
+         * might have
+         *
+         * [sector_num+x, nr_sectors] allocated.
+         */
+        if (n > pnum_inter &&
+            (intermediate == top ||
+             sector_num + pnum_inter < intermediate->total_sectors)) {
+            n = pnum_inter;
+        }
+
+        intermediate = intermediate->backing_hd;
+    }
+
+    *pnum = n;
+    return 0;
+}
+
+/* Coroutine wrapper for bdrv_is_allocated_above() */
+static void coroutine_fn bdrv_is_allocated_above_co_entry(void *opaque)
+{
+    BdrvCoIsAllocatedData *data = opaque;
+    BlockDriverState *top = data->bs;
+    BlockDriverState *base = data->base;
+
+    data->ret = bdrv_co_is_allocated_above(top, base, data->sector_num,
+                                           data->nb_sectors, data->pnum);
+    data->done = true;
+}
+
+/*
+ * Synchronous wrapper around bdrv_co_is_allocated_above().
+ *
+ * See bdrv_co_is_allocated_above() for details.
+ */
+int bdrv_is_allocated_above(BlockDriverState *top, BlockDriverState *base,
+                            int64_t sector_num, int nb_sectors, int *pnum)
+{
+    Coroutine *co;
+    BdrvCoIsAllocatedData data = {
+        .bs = top,
+        .base = base,
+        .sector_num = sector_num,
+        .nb_sectors = nb_sectors,
+        .pnum = pnum,
+        .done = false,
+    };
+
+    co = qemu_coroutine_create(bdrv_is_allocated_above_co_entry);
+    qemu_coroutine_enter(co, &data);
+    while (!data.done) {
+        qemu_aio_wait();
+    }
+    return data.ret;
+}
+
+const char *bdrv_get_encrypted_filename(BlockDriverState *bs)
+{
+    if (bs->backing_hd && bs->backing_hd->encrypted)
+        return bs->backing_file;
+    else if (bs->encrypted)
+        return bs->filename;
+    else
+        return NULL;
+}
+
+void bdrv_get_backing_filename(BlockDriverState *bs,
+                               char *filename, int filename_size)
+{
+    pstrcpy(filename, filename_size, bs->backing_file);
+}
+
+int bdrv_write_compressed(BlockDriverState *bs, int64_t sector_num,
+                          const uint8_t *buf, int nb_sectors)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv)
+        return -ENOMEDIUM;
+    if (!drv->bdrv_write_compressed)
+        return -ENOTSUP;
+    if (bdrv_check_request(bs, sector_num, nb_sectors))
+        return -EIO;
+
+    assert(!bs->dirty_bitmap);
+
+    return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
+}
+
+int bdrv_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv)
+        return -ENOMEDIUM;
+    if (!drv->bdrv_get_info)
+        return -ENOTSUP;
+    memset(bdi, 0, sizeof(*bdi));
+    return drv->bdrv_get_info(bs, bdi);
+}
+
+int bdrv_save_vmstate(BlockDriverState *bs, const uint8_t *buf,
+                      int64_t pos, int size)
+{
+    QEMUIOVector qiov;
+    struct iovec iov = {
+        .iov_base   = (void *) buf,
+        .iov_len    = size,
+    };
+
+    qemu_iovec_init_external(&qiov, &iov, 1);
+    return bdrv_writev_vmstate(bs, &qiov, pos);
+}
+
+int bdrv_writev_vmstate(BlockDriverState *bs, QEMUIOVector *qiov, int64_t pos)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (!drv) {
+        return -ENOMEDIUM;
+    } else if (drv->bdrv_save_vmstate) {
+        return drv->bdrv_save_vmstate(bs, qiov, pos);
+    } else if (bs->file) {
+        return bdrv_writev_vmstate(bs->file, qiov, pos);
+    }
+
+    return -ENOTSUP;
+}
+
+int bdrv_load_vmstate(BlockDriverState *bs, uint8_t *buf,
+                      int64_t pos, int size)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv)
+        return -ENOMEDIUM;
+    if (drv->bdrv_load_vmstate)
+        return drv->bdrv_load_vmstate(bs, buf, pos, size);
+    if (bs->file)
+        return bdrv_load_vmstate(bs->file, buf, pos, size);
+    return -ENOTSUP;
+}
+
+void bdrv_debug_event(BlockDriverState *bs, BlkDebugEvent event)
+{
+    if (!bs || !bs->drv || !bs->drv->bdrv_debug_event) {
+        return;
+    }
+
+    bs->drv->bdrv_debug_event(bs, event);
+}
+
+int bdrv_debug_breakpoint(BlockDriverState *bs, const char *event,
+                          const char *tag)
+{
+    while (bs && bs->drv && !bs->drv->bdrv_debug_breakpoint) {
+        bs = bs->file;
+    }
+
+    if (bs && bs->drv && bs->drv->bdrv_debug_breakpoint) {
+        return bs->drv->bdrv_debug_breakpoint(bs, event, tag);
+    }
+
+    return -ENOTSUP;
+}
+
+int bdrv_debug_resume(BlockDriverState *bs, const char *tag)
+{
+    while (bs && bs->drv && !bs->drv->bdrv_debug_resume) {
+        bs = bs->file;
+    }
+
+    if (bs && bs->drv && bs->drv->bdrv_debug_resume) {
+        return bs->drv->bdrv_debug_resume(bs, tag);
+    }
+
+    return -ENOTSUP;
+}
+
+bool bdrv_debug_is_suspended(BlockDriverState *bs, const char *tag)
+{
+    while (bs && bs->drv && !bs->drv->bdrv_debug_is_suspended) {
+        bs = bs->file;
+    }
+
+    if (bs && bs->drv && bs->drv->bdrv_debug_is_suspended) {
+        return bs->drv->bdrv_debug_is_suspended(bs, tag);
+    }
+
+    return false;
+}
+
+int bdrv_is_snapshot(BlockDriverState *bs)
+{
+    return !!(bs->open_flags & BDRV_O_SNAPSHOT);
+}
+
+/* backing_file can either be relative, or absolute, or a protocol.  If it is
+ * relative, it must be relative to the chain.  So, passing in bs->filename
+ * from a BDS as backing_file should not be done, as that may be relative to
+ * the CWD rather than the chain. */
+BlockDriverState *bdrv_find_backing_image(BlockDriverState *bs,
+        const char *backing_file)
+{
+    char *filename_full = NULL;
+    char *backing_file_full = NULL;
+    char *filename_tmp = NULL;
+    int is_protocol = 0;
+    BlockDriverState *curr_bs = NULL;
+    BlockDriverState *retval = NULL;
+
+    if (!bs || !bs->drv || !backing_file) {
+        return NULL;
+    }
+
+    filename_full     = g_malloc(PATH_MAX);
+    backing_file_full = g_malloc(PATH_MAX);
+    filename_tmp      = g_malloc(PATH_MAX);
+
+    is_protocol = path_has_protocol(backing_file);
+
+    for (curr_bs = bs; curr_bs->backing_hd; curr_bs = curr_bs->backing_hd) {
+
+        /* If either of the filename paths is actually a protocol, then
+         * compare unmodified paths; otherwise make paths relative */
+        if (is_protocol || path_has_protocol(curr_bs->backing_file)) {
+            if (strcmp(backing_file, curr_bs->backing_file) == 0) {
+                retval = curr_bs->backing_hd;
+                break;
+            }
+        } else {
+            /* If not an absolute filename path, make it relative to the current
+             * image's filename path */
+            path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
+                         backing_file);
+
+            /* We are going to compare absolute pathnames */
+            if (!realpath(filename_tmp, filename_full)) {
+                continue;
+            }
+
+            /* We need to make sure the backing filename we are comparing against
+             * is relative to the current image filename (or absolute) */
+            path_combine(filename_tmp, PATH_MAX, curr_bs->filename,
+                         curr_bs->backing_file);
+
+            if (!realpath(filename_tmp, backing_file_full)) {
+                continue;
+            }
+
+            if (strcmp(backing_file_full, filename_full) == 0) {
+                retval = curr_bs->backing_hd;
+                break;
+            }
+        }
+    }
+
+    g_free(filename_full);
+    g_free(backing_file_full);
+    g_free(filename_tmp);
+    return retval;
+}
+
+int bdrv_get_backing_file_depth(BlockDriverState *bs)
+{
+    if (!bs->drv) {
+        return 0;
+    }
+
+    if (!bs->backing_hd) {
+        return 0;
+    }
+
+    return 1 + bdrv_get_backing_file_depth(bs->backing_hd);
+}
+
+BlockDriverState *bdrv_find_base(BlockDriverState *bs)
+{
+    BlockDriverState *curr_bs = NULL;
+
+    if (!bs) {
+        return NULL;
+    }
+
+    curr_bs = bs;
+
+    while (curr_bs->backing_hd) {
+        curr_bs = curr_bs->backing_hd;
+    }
+    return curr_bs;
+}
+
+/**************************************************************/
+/* async I/Os */
+
+BlockDriverAIOCB *bdrv_aio_readv(BlockDriverState *bs, int64_t sector_num,
+                                 QEMUIOVector *qiov, int nb_sectors,
+                                 BlockDriverCompletionFunc *cb, void *opaque)
+{
+    trace_bdrv_aio_readv(bs, sector_num, nb_sectors, opaque);
+
+    return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors,
+                                 cb, opaque, false);
+}
+
+BlockDriverAIOCB *bdrv_aio_writev(BlockDriverState *bs, int64_t sector_num,
+                                  QEMUIOVector *qiov, int nb_sectors,
+                                  BlockDriverCompletionFunc *cb, void *opaque)
+{
+    trace_bdrv_aio_writev(bs, sector_num, nb_sectors, opaque);
+
+    return bdrv_co_aio_rw_vector(bs, sector_num, qiov, nb_sectors,
+                                 cb, opaque, true);
+}
+
+
+typedef struct MultiwriteCB {
+    int error;
+    int num_requests;
+    int num_callbacks;
+    struct {
+        BlockDriverCompletionFunc *cb;
+        void *opaque;
+        QEMUIOVector *free_qiov;
+    } callbacks[];
+} MultiwriteCB;
+
+static void multiwrite_user_cb(MultiwriteCB *mcb)
+{
+    int i;
+
+    for (i = 0; i < mcb->num_callbacks; i++) {
+        mcb->callbacks[i].cb(mcb->callbacks[i].opaque, mcb->error);
+        if (mcb->callbacks[i].free_qiov) {
+            qemu_iovec_destroy(mcb->callbacks[i].free_qiov);
+        }
+        g_free(mcb->callbacks[i].free_qiov);
+    }
+}
+
+static void multiwrite_cb(void *opaque, int ret)
+{
+    MultiwriteCB *mcb = opaque;
+
+    trace_multiwrite_cb(mcb, ret);
+
+    if (ret < 0 && !mcb->error) {
+        mcb->error = ret;
+    }
+
+    mcb->num_requests--;
+    if (mcb->num_requests == 0) {
+        multiwrite_user_cb(mcb);
+        g_free(mcb);
+    }
+}
+
+static int multiwrite_req_compare(const void *a, const void *b)
+{
+    const BlockRequest *req1 = a, *req2 = b;
+
+    /*
+     * Note that we can't simply subtract req2->sector from req1->sector
+     * here as that could overflow the return value.
+     */
+    if (req1->sector > req2->sector) {
+        return 1;
+    } else if (req1->sector < req2->sector) {
+        return -1;
+    } else {
+        return 0;
+    }
+}
+
+/*
+ * Takes a bunch of requests and tries to merge them. Returns the number of
+ * requests that remain after merging.
+ */
+static int multiwrite_merge(BlockDriverState *bs, BlockRequest *reqs,
+    int num_reqs, MultiwriteCB *mcb)
+{
+    int i, outidx;
+
+    // Sort requests by start sector
+    qsort(reqs, num_reqs, sizeof(*reqs), &multiwrite_req_compare);
+
+    // Check if adjacent requests touch the same clusters. If so, combine them,
+    // filling up gaps with zero sectors.
+    outidx = 0;
+    for (i = 1; i < num_reqs; i++) {
+        int merge = 0;
+        int64_t oldreq_last = reqs[outidx].sector + reqs[outidx].nb_sectors;
+
+        // Handle exactly sequential writes and overlapping writes.
+        if (reqs[i].sector <= oldreq_last) {
+            merge = 1;
+        }
+
+        if (reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1 > IOV_MAX) {
+            merge = 0;
+        }
+
+        if (merge) {
+            size_t size;
+            QEMUIOVector *qiov = g_malloc0(sizeof(*qiov));
+            qemu_iovec_init(qiov,
+                reqs[outidx].qiov->niov + reqs[i].qiov->niov + 1);
+
+            // Add the first request to the merged one. If the requests are
+            // overlapping, drop the last sectors of the first request.
+            size = (reqs[i].sector - reqs[outidx].sector) << 9;
+            qemu_iovec_concat(qiov, reqs[outidx].qiov, 0, size);
+
+            // We should need to add any zeros between the two requests
+            assert (reqs[i].sector <= oldreq_last);
+
+            // Add the second request
+            qemu_iovec_concat(qiov, reqs[i].qiov, 0, reqs[i].qiov->size);
+
+            reqs[outidx].nb_sectors = qiov->size >> 9;
+            reqs[outidx].qiov = qiov;
+
+            mcb->callbacks[i].free_qiov = reqs[outidx].qiov;
+        } else {
+            outidx++;
+            reqs[outidx].sector     = reqs[i].sector;
+            reqs[outidx].nb_sectors = reqs[i].nb_sectors;
+            reqs[outidx].qiov       = reqs[i].qiov;
+        }
+    }
+
+    return outidx + 1;
+}
+
+/*
+ * Submit multiple AIO write requests at once.
+ *
+ * On success, the function returns 0 and all requests in the reqs array have
+ * been submitted. In error case this function returns -1, and any of the
+ * requests may or may not be submitted yet. In particular, this means that the
+ * callback will be called for some of the requests, for others it won't. The
+ * caller must check the error field of the BlockRequest to wait for the right
+ * callbacks (if error != 0, no callback will be called).
+ *
+ * The implementation may modify the contents of the reqs array, e.g. to merge
+ * requests. However, the fields opaque and error are left unmodified as they
+ * are used to signal failure for a single request to the caller.
+ */
+int bdrv_aio_multiwrite(BlockDriverState *bs, BlockRequest *reqs, int num_reqs)
+{
+    MultiwriteCB *mcb;
+    int i;
+
+    /* don't submit writes if we don't have a medium */
+    if (bs->drv == NULL) {
+        for (i = 0; i < num_reqs; i++) {
+            reqs[i].error = -ENOMEDIUM;
+        }
+        return -1;
+    }
+
+    if (num_reqs == 0) {
+        return 0;
+    }
+
+    // Create MultiwriteCB structure
+    mcb = g_malloc0(sizeof(*mcb) + num_reqs * sizeof(*mcb->callbacks));
+    mcb->num_requests = 0;
+    mcb->num_callbacks = num_reqs;
+
+    for (i = 0; i < num_reqs; i++) {
+        mcb->callbacks[i].cb = reqs[i].cb;
+        mcb->callbacks[i].opaque = reqs[i].opaque;
+    }
+
+    // Check for mergable requests
+    num_reqs = multiwrite_merge(bs, reqs, num_reqs, mcb);
+
+    trace_bdrv_aio_multiwrite(mcb, mcb->num_callbacks, num_reqs);
+
+    /* Run the aio requests. */
+    mcb->num_requests = num_reqs;
+    for (i = 0; i < num_reqs; i++) {
+        bdrv_aio_writev(bs, reqs[i].sector, reqs[i].qiov,
+            reqs[i].nb_sectors, multiwrite_cb, mcb);
+    }
+
+    return 0;
+}
+
+void bdrv_aio_cancel(BlockDriverAIOCB *acb)
+{
+    acb->aiocb_info->cancel(acb);
+}
+
+/* block I/O throttling */
+static bool bdrv_exceed_bps_limits(BlockDriverState *bs, int nb_sectors,
+                 bool is_write, double elapsed_time, uint64_t *wait)
+{
+    uint64_t bps_limit = 0;
+    uint64_t extension;
+    double   bytes_limit, bytes_base, bytes_res;
+    double   slice_time, wait_time;
+
+    if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) {
+        bps_limit = bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL];
+    } else if (bs->io_limits.bps[is_write]) {
+        bps_limit = bs->io_limits.bps[is_write];
+    } else {
+        if (wait) {
+            *wait = 0;
+        }
+
+        return false;
+    }
+
+    slice_time = bs->slice_end - bs->slice_start;
+    slice_time /= (NANOSECONDS_PER_SECOND);
+    bytes_limit = bps_limit * slice_time;
+    bytes_base  = bs->slice_submitted.bytes[is_write];
+    if (bs->io_limits.bps[BLOCK_IO_LIMIT_TOTAL]) {
+        bytes_base += bs->slice_submitted.bytes[!is_write];
+    }
+
+    /* bytes_base: the bytes of data which have been read/written; and
+     *             it is obtained from the history statistic info.
+     * bytes_res: the remaining bytes of data which need to be read/written.
+     * (bytes_base + bytes_res) / bps_limit: used to calcuate
+     *             the total time for completing reading/writting all data.
+     */
+    bytes_res   = (unsigned) nb_sectors * BDRV_SECTOR_SIZE;
+
+    if (bytes_base + bytes_res <= bytes_limit) {
+        if (wait) {
+            *wait = 0;
+        }
+
+        return false;
+    }
+
+    /* Calc approx time to dispatch */
+    wait_time = (bytes_base + bytes_res) / bps_limit - elapsed_time;
+
+    /* When the I/O rate at runtime exceeds the limits,
+     * bs->slice_end need to be extended in order that the current statistic
+     * info can be kept until the timer fire, so it is increased and tuned
+     * based on the result of experiment.
+     */
+    extension = wait_time * NANOSECONDS_PER_SECOND;
+    extension = DIV_ROUND_UP(extension, BLOCK_IO_SLICE_TIME) *
+                BLOCK_IO_SLICE_TIME;
+    bs->slice_end += extension;
+    if (wait) {
+        *wait = wait_time * NANOSECONDS_PER_SECOND;
+    }
+
+    return true;
+}
+
+static bool bdrv_exceed_iops_limits(BlockDriverState *bs, bool is_write,
+                             double elapsed_time, uint64_t *wait)
+{
+    uint64_t iops_limit = 0;
+    double   ios_limit, ios_base;
+    double   slice_time, wait_time;
+
+    if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) {
+        iops_limit = bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL];
+    } else if (bs->io_limits.iops[is_write]) {
+        iops_limit = bs->io_limits.iops[is_write];
+    } else {
+        if (wait) {
+            *wait = 0;
+        }
+
+        return false;
+    }
+
+    slice_time = bs->slice_end - bs->slice_start;
+    slice_time /= (NANOSECONDS_PER_SECOND);
+    ios_limit  = iops_limit * slice_time;
+    ios_base   = bs->slice_submitted.ios[is_write];
+    if (bs->io_limits.iops[BLOCK_IO_LIMIT_TOTAL]) {
+        ios_base += bs->slice_submitted.ios[!is_write];
+    }
+
+    if (ios_base + 1 <= ios_limit) {
+        if (wait) {
+            *wait = 0;
+        }
+
+        return false;
+    }
+
+    /* Calc approx time to dispatch, in seconds */
+    wait_time = (ios_base + 1) / iops_limit;
+    if (wait_time > elapsed_time) {
+        wait_time = wait_time - elapsed_time;
+    } else {
+        wait_time = 0;
+    }
+
+    /* Exceeded current slice, extend it by another slice time */
+    bs->slice_end += BLOCK_IO_SLICE_TIME;
+    if (wait) {
+        *wait = wait_time * NANOSECONDS_PER_SECOND;
+    }
+
+    return true;
+}
+
+static bool bdrv_exceed_io_limits(BlockDriverState *bs, int nb_sectors,
+                           bool is_write, int64_t *wait)
+{
+    int64_t  now, max_wait;
+    uint64_t bps_wait = 0, iops_wait = 0;
+    double   elapsed_time;
+    int      bps_ret, iops_ret;
+
+    now = qemu_get_clock_ns(vm_clock);
+    if (now > bs->slice_end) {
+        bs->slice_start = now;
+        bs->slice_end   = now + BLOCK_IO_SLICE_TIME;
+        memset(&bs->slice_submitted, 0, sizeof(bs->slice_submitted));
+    }
+
+    elapsed_time  = now - bs->slice_start;
+    elapsed_time  /= (NANOSECONDS_PER_SECOND);
+
+    bps_ret  = bdrv_exceed_bps_limits(bs, nb_sectors,
+                                      is_write, elapsed_time, &bps_wait);
+    iops_ret = bdrv_exceed_iops_limits(bs, is_write,
+                                      elapsed_time, &iops_wait);
+    if (bps_ret || iops_ret) {
+        max_wait = bps_wait > iops_wait ? bps_wait : iops_wait;
+        if (wait) {
+            *wait = max_wait;
+        }
+
+        now = qemu_get_clock_ns(vm_clock);
+        if (bs->slice_end < now + max_wait) {
+            bs->slice_end = now + max_wait;
+        }
+
+        return true;
+    }
+
+    if (wait) {
+        *wait = 0;
+    }
+
+    bs->slice_submitted.bytes[is_write] += (int64_t)nb_sectors *
+                                           BDRV_SECTOR_SIZE;
+    bs->slice_submitted.ios[is_write]++;
+
+    return false;
+}
+
+/**************************************************************/
+/* async block device emulation */
+
+typedef struct BlockDriverAIOCBSync {
+    BlockDriverAIOCB common;
+    QEMUBH *bh;
+    int ret;
+    /* vector translation state */
+    QEMUIOVector *qiov;
+    uint8_t *bounce;
+    int is_write;
+} BlockDriverAIOCBSync;
+
+static void bdrv_aio_cancel_em(BlockDriverAIOCB *blockacb)
+{
+    BlockDriverAIOCBSync *acb =
+        container_of(blockacb, BlockDriverAIOCBSync, common);
+    qemu_bh_delete(acb->bh);
+    acb->bh = NULL;
+    qemu_aio_release(acb);
+}
+
+static const AIOCBInfo bdrv_em_aiocb_info = {
+    .aiocb_size         = sizeof(BlockDriverAIOCBSync),
+    .cancel             = bdrv_aio_cancel_em,
+};
+
+static void bdrv_aio_bh_cb(void *opaque)
+{
+    BlockDriverAIOCBSync *acb = opaque;
+
+    if (!acb->is_write)
+        qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size);
+    qemu_vfree(acb->bounce);
+    acb->common.cb(acb->common.opaque, acb->ret);
+    qemu_bh_delete(acb->bh);
+    acb->bh = NULL;
+    qemu_aio_release(acb);
+}
+
+static BlockDriverAIOCB *bdrv_aio_rw_vector(BlockDriverState *bs,
+                                            int64_t sector_num,
+                                            QEMUIOVector *qiov,
+                                            int nb_sectors,
+                                            BlockDriverCompletionFunc *cb,
+                                            void *opaque,
+                                            int is_write)
+
+{
+    BlockDriverAIOCBSync *acb;
+
+    acb = qemu_aio_get(&bdrv_em_aiocb_info, bs, cb, opaque);
+    acb->is_write = is_write;
+    acb->qiov = qiov;
+    acb->bounce = qemu_blockalign(bs, qiov->size);
+    acb->bh = qemu_bh_new(bdrv_aio_bh_cb, acb);
+
+    if (is_write) {
+        qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size);
+        acb->ret = bs->drv->bdrv_write(bs, sector_num, acb->bounce, nb_sectors);
+    } else {
+        acb->ret = bs->drv->bdrv_read(bs, sector_num, acb->bounce, nb_sectors);
+    }
+
+    qemu_bh_schedule(acb->bh);
+
+    return &acb->common;
+}
+
+static BlockDriverAIOCB *bdrv_aio_readv_em(BlockDriverState *bs,
+        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
+}
+
+static BlockDriverAIOCB *bdrv_aio_writev_em(BlockDriverState *bs,
+        int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    return bdrv_aio_rw_vector(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
+}
+
+
+typedef struct BlockDriverAIOCBCoroutine {
+    BlockDriverAIOCB common;
+    BlockRequest req;
+    bool is_write;
+    bool *done;
+    QEMUBH* bh;
+} BlockDriverAIOCBCoroutine;
+
+static void bdrv_aio_co_cancel_em(BlockDriverAIOCB *blockacb)
+{
+    BlockDriverAIOCBCoroutine *acb =
+        container_of(blockacb, BlockDriverAIOCBCoroutine, common);
+    bool done = false;
+
+    acb->done = &done;
+    while (!done) {
+        qemu_aio_wait();
+    }
+}
+
+static const AIOCBInfo bdrv_em_co_aiocb_info = {
+    .aiocb_size         = sizeof(BlockDriverAIOCBCoroutine),
+    .cancel             = bdrv_aio_co_cancel_em,
+};
+
+static void bdrv_co_em_bh(void *opaque)
+{
+    BlockDriverAIOCBCoroutine *acb = opaque;
+
+    acb->common.cb(acb->common.opaque, acb->req.error);
+
+    if (acb->done) {
+        *acb->done = true;
+    }
+
+    qemu_bh_delete(acb->bh);
+    qemu_aio_release(acb);
+}
+
+/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */
+static void coroutine_fn bdrv_co_do_rw(void *opaque)
+{
+    BlockDriverAIOCBCoroutine *acb = opaque;
+    BlockDriverState *bs = acb->common.bs;
+
+    if (!acb->is_write) {
+        acb->req.error = bdrv_co_do_readv(bs, acb->req.sector,
+            acb->req.nb_sectors, acb->req.qiov, 0);
+    } else {
+        acb->req.error = bdrv_co_do_writev(bs, acb->req.sector,
+            acb->req.nb_sectors, acb->req.qiov, 0);
+    }
+
+    acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
+    qemu_bh_schedule(acb->bh);
+}
+
+static BlockDriverAIOCB *bdrv_co_aio_rw_vector(BlockDriverState *bs,
+                                               int64_t sector_num,
+                                               QEMUIOVector *qiov,
+                                               int nb_sectors,
+                                               BlockDriverCompletionFunc *cb,
+                                               void *opaque,
+                                               bool is_write)
+{
+    Coroutine *co;
+    BlockDriverAIOCBCoroutine *acb;
+
+    acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
+    acb->req.sector = sector_num;
+    acb->req.nb_sectors = nb_sectors;
+    acb->req.qiov = qiov;
+    acb->is_write = is_write;
+    acb->done = NULL;
+
+    co = qemu_coroutine_create(bdrv_co_do_rw);
+    qemu_coroutine_enter(co, acb);
+
+    return &acb->common;
+}
+
+static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque)
+{
+    BlockDriverAIOCBCoroutine *acb = opaque;
+    BlockDriverState *bs = acb->common.bs;
+
+    acb->req.error = bdrv_co_flush(bs);
+    acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
+    qemu_bh_schedule(acb->bh);
+}
+
+BlockDriverAIOCB *bdrv_aio_flush(BlockDriverState *bs,
+        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    trace_bdrv_aio_flush(bs, opaque);
+
+    Coroutine *co;
+    BlockDriverAIOCBCoroutine *acb;
+
+    acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
+    acb->done = NULL;
+
+    co = qemu_coroutine_create(bdrv_aio_flush_co_entry);
+    qemu_coroutine_enter(co, acb);
+
+    return &acb->common;
+}
+
+static void coroutine_fn bdrv_aio_discard_co_entry(void *opaque)
+{
+    BlockDriverAIOCBCoroutine *acb = opaque;
+    BlockDriverState *bs = acb->common.bs;
+
+    acb->req.error = bdrv_co_discard(bs, acb->req.sector, acb->req.nb_sectors);
+    acb->bh = qemu_bh_new(bdrv_co_em_bh, acb);
+    qemu_bh_schedule(acb->bh);
+}
+
+BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
+        int64_t sector_num, int nb_sectors,
+        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    Coroutine *co;
+    BlockDriverAIOCBCoroutine *acb;
+
+    trace_bdrv_aio_discard(bs, sector_num, nb_sectors, opaque);
+
+    acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
+    acb->req.sector = sector_num;
+    acb->req.nb_sectors = nb_sectors;
+    acb->done = NULL;
+    co = qemu_coroutine_create(bdrv_aio_discard_co_entry);
+    qemu_coroutine_enter(co, acb);
+
+    return &acb->common;
+}
+
+void bdrv_init(void)
+{
+    module_call_init(MODULE_INIT_BLOCK);
+}
+
+void bdrv_init_with_whitelist(void)
+{
+    use_bdrv_whitelist = 1;
+    bdrv_init();
+}
+
+void *qemu_aio_get(const AIOCBInfo *aiocb_info, BlockDriverState *bs,
+                   BlockDriverCompletionFunc *cb, void *opaque)
+{
+    BlockDriverAIOCB *acb;
+
+    acb = g_slice_alloc(aiocb_info->aiocb_size);
+    acb->aiocb_info = aiocb_info;
+    acb->bs = bs;
+    acb->cb = cb;
+    acb->opaque = opaque;
+    return acb;
+}
+
+void qemu_aio_release(void *p)
+{
+    BlockDriverAIOCB *acb = p;
+    g_slice_free1(acb->aiocb_info->aiocb_size, acb);
+}
+
+/**************************************************************/
+/* Coroutine block device emulation */
+
+typedef struct CoroutineIOCompletion {
+    Coroutine *coroutine;
+    int ret;
+} CoroutineIOCompletion;
+
+static void bdrv_co_io_em_complete(void *opaque, int ret)
+{
+    CoroutineIOCompletion *co = opaque;
+
+    co->ret = ret;
+    qemu_coroutine_enter(co->coroutine, NULL);
+}
+
+static int coroutine_fn bdrv_co_io_em(BlockDriverState *bs, int64_t sector_num,
+                                      int nb_sectors, QEMUIOVector *iov,
+                                      bool is_write)
+{
+    CoroutineIOCompletion co = {
+        .coroutine = qemu_coroutine_self(),
+    };
+    BlockDriverAIOCB *acb;
+
+    if (is_write) {
+        acb = bs->drv->bdrv_aio_writev(bs, sector_num, iov, nb_sectors,
+                                       bdrv_co_io_em_complete, &co);
+    } else {
+        acb = bs->drv->bdrv_aio_readv(bs, sector_num, iov, nb_sectors,
+                                      bdrv_co_io_em_complete, &co);
+    }
+
+    trace_bdrv_co_io_em(bs, sector_num, nb_sectors, is_write, acb);
+    if (!acb) {
+        return -EIO;
+    }
+    qemu_coroutine_yield();
+
+    return co.ret;
+}
+
+static int coroutine_fn bdrv_co_readv_em(BlockDriverState *bs,
+                                         int64_t sector_num, int nb_sectors,
+                                         QEMUIOVector *iov)
+{
+    return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, false);
+}
+
+static int coroutine_fn bdrv_co_writev_em(BlockDriverState *bs,
+                                         int64_t sector_num, int nb_sectors,
+                                         QEMUIOVector *iov)
+{
+    return bdrv_co_io_em(bs, sector_num, nb_sectors, iov, true);
+}
+
+static void coroutine_fn bdrv_flush_co_entry(void *opaque)
+{
+    RwCo *rwco = opaque;
+
+    rwco->ret = bdrv_co_flush(rwco->bs);
+}
+
+int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
+{
+    int ret;
+
+    if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
+        return 0;
+    }
+
+    /* Write back cached data to the OS even with cache=unsafe */
+    BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS);
+    if (bs->drv->bdrv_co_flush_to_os) {
+        ret = bs->drv->bdrv_co_flush_to_os(bs);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    /* But don't actually force it to the disk with cache=unsafe */
+    if (bs->open_flags & BDRV_O_NO_FLUSH) {
+        goto flush_parent;
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_DISK);
+    if (bs->drv->bdrv_co_flush_to_disk) {
+        ret = bs->drv->bdrv_co_flush_to_disk(bs);
+    } else if (bs->drv->bdrv_aio_flush) {
+        BlockDriverAIOCB *acb;
+        CoroutineIOCompletion co = {
+            .coroutine = qemu_coroutine_self(),
+        };
+
+        acb = bs->drv->bdrv_aio_flush(bs, bdrv_co_io_em_complete, &co);
+        if (acb == NULL) {
+            ret = -EIO;
+        } else {
+            qemu_coroutine_yield();
+            ret = co.ret;
+        }
+    } else {
+        /*
+         * Some block drivers always operate in either writethrough or unsafe
+         * mode and don't support bdrv_flush therefore. Usually qemu doesn't
+         * know how the server works (because the behaviour is hardcoded or
+         * depends on server-side configuration), so we can't ensure that
+         * everything is safe on disk. Returning an error doesn't work because
+         * that would break guests even if the server operates in writethrough
+         * mode.
+         *
+         * Let's hope the user knows what he's doing.
+         */
+        ret = 0;
+    }
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Now flush the underlying protocol.  It will also have BDRV_O_NO_FLUSH
+     * in the case of cache=unsafe, so there are no useless flushes.
+     */
+flush_parent:
+    return bdrv_co_flush(bs->file);
+}
+
+void bdrv_invalidate_cache(BlockDriverState *bs)
+{
+    if (bs->drv && bs->drv->bdrv_invalidate_cache) {
+        bs->drv->bdrv_invalidate_cache(bs);
+    }
+}
+
+void bdrv_invalidate_cache_all(void)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        bdrv_invalidate_cache(bs);
+    }
+}
+
+void bdrv_clear_incoming_migration_all(void)
+{
+    BlockDriverState *bs;
+
+    QTAILQ_FOREACH(bs, &bdrv_states, list) {
+        bs->open_flags = bs->open_flags & ~(BDRV_O_INCOMING);
+    }
+}
+
+int bdrv_flush(BlockDriverState *bs)
+{
+    Coroutine *co;
+    RwCo rwco = {
+        .bs = bs,
+        .ret = NOT_DONE,
+    };
+
+    if (qemu_in_coroutine()) {
+        /* Fast-path if already in coroutine context */
+        bdrv_flush_co_entry(&rwco);
+    } else {
+        co = qemu_coroutine_create(bdrv_flush_co_entry);
+        qemu_coroutine_enter(co, &rwco);
+        while (rwco.ret == NOT_DONE) {
+            qemu_aio_wait();
+        }
+    }
+
+    return rwco.ret;
+}
+
+static void coroutine_fn bdrv_discard_co_entry(void *opaque)
+{
+    RwCo *rwco = opaque;
+
+    rwco->ret = bdrv_co_discard(rwco->bs, rwco->sector_num, rwco->nb_sectors);
+}
+
+int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
+                                 int nb_sectors)
+{
+    if (!bs->drv) {
+        return -ENOMEDIUM;
+    } else if (bdrv_check_request(bs, sector_num, nb_sectors)) {
+        return -EIO;
+    } else if (bs->read_only) {
+        return -EROFS;
+    }
+
+    if (bs->dirty_bitmap) {
+        bdrv_reset_dirty(bs, sector_num, nb_sectors);
+    }
+
+    /* Do nothing if disabled.  */
+    if (!(bs->open_flags & BDRV_O_UNMAP)) {
+        return 0;
+    }
+
+    if (bs->drv->bdrv_co_discard) {
+        return bs->drv->bdrv_co_discard(bs, sector_num, nb_sectors);
+    } else if (bs->drv->bdrv_aio_discard) {
+        BlockDriverAIOCB *acb;
+        CoroutineIOCompletion co = {
+            .coroutine = qemu_coroutine_self(),
+        };
+
+        acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,
+                                        bdrv_co_io_em_complete, &co);
+        if (acb == NULL) {
+            return -EIO;
+        } else {
+            qemu_coroutine_yield();
+            return co.ret;
+        }
+    } else {
+        return 0;
+    }
+}
+
+int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
+{
+    Coroutine *co;
+    RwCo rwco = {
+        .bs = bs,
+        .sector_num = sector_num,
+        .nb_sectors = nb_sectors,
+        .ret = NOT_DONE,
+    };
+
+    if (qemu_in_coroutine()) {
+        /* Fast-path if already in coroutine context */
+        bdrv_discard_co_entry(&rwco);
+    } else {
+        co = qemu_coroutine_create(bdrv_discard_co_entry);
+        qemu_coroutine_enter(co, &rwco);
+        while (rwco.ret == NOT_DONE) {
+            qemu_aio_wait();
+        }
+    }
+
+    return rwco.ret;
+}
+
+/**************************************************************/
+/* removable device support */
+
+/**
+ * Return TRUE if the media is present
+ */
+int bdrv_is_inserted(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (!drv)
+        return 0;
+    if (!drv->bdrv_is_inserted)
+        return 1;
+    return drv->bdrv_is_inserted(bs);
+}
+
+/**
+ * Return whether the media changed since the last call to this
+ * function, or -ENOTSUP if we don't know.  Most drivers don't know.
+ */
+int bdrv_media_changed(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_media_changed) {
+        return drv->bdrv_media_changed(bs);
+    }
+    return -ENOTSUP;
+}
+
+/**
+ * If eject_flag is TRUE, eject the media. Otherwise, close the tray
+ */
+void bdrv_eject(BlockDriverState *bs, bool eject_flag)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_eject) {
+        drv->bdrv_eject(bs, eject_flag);
+    }
+
+    if (bs->device_name[0] != '\0') {
+        bdrv_emit_qmp_eject_event(bs, eject_flag);
+    }
+}
+
+/**
+ * Lock or unlock the media (if it is locked, the user won't be able
+ * to eject it manually).
+ */
+void bdrv_lock_medium(BlockDriverState *bs, bool locked)
+{
+    BlockDriver *drv = bs->drv;
+
+    trace_bdrv_lock_medium(bs, locked);
+
+    if (drv && drv->bdrv_lock_medium) {
+        drv->bdrv_lock_medium(bs, locked);
+    }
+}
+
+/* needed for generic scsi interface */
+
+int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_ioctl)
+        return drv->bdrv_ioctl(bs, req, buf);
+    return -ENOTSUP;
+}
+
+BlockDriverAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
+        unsigned long int req, void *buf,
+        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    BlockDriver *drv = bs->drv;
+
+    if (drv && drv->bdrv_aio_ioctl)
+        return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
+    return NULL;
+}
+
+void bdrv_set_buffer_alignment(BlockDriverState *bs, int align)
+{
+    bs->buffer_alignment = align;
+}
+
+void *qemu_blockalign(BlockDriverState *bs, size_t size)
+{
+    return qemu_memalign((bs && bs->buffer_alignment) ? bs->buffer_alignment : 512, size);
+}
+
+/*
+ * Check if all memory in this vector is sector aligned.
+ */
+bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov)
+{
+    int i;
+
+    for (i = 0; i < qiov->niov; i++) {
+        if ((uintptr_t) qiov->iov[i].iov_base % bs->buffer_alignment) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
+void bdrv_set_dirty_tracking(BlockDriverState *bs, int granularity)
+{
+    int64_t bitmap_size;
+
+    assert((granularity & (granularity - 1)) == 0);
+
+    if (granularity) {
+        granularity >>= BDRV_SECTOR_BITS;
+        assert(!bs->dirty_bitmap);
+        bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS);
+        bs->dirty_bitmap = hbitmap_alloc(bitmap_size, ffs(granularity) - 1);
+    } else {
+        if (bs->dirty_bitmap) {
+            hbitmap_free(bs->dirty_bitmap);
+            bs->dirty_bitmap = NULL;
+        }
+    }
+}
+
+int bdrv_get_dirty(BlockDriverState *bs, int64_t sector)
+{
+    if (bs->dirty_bitmap) {
+        return hbitmap_get(bs->dirty_bitmap, sector);
+    } else {
+        return 0;
+    }
+}
+
+void bdrv_dirty_iter_init(BlockDriverState *bs, HBitmapIter *hbi)
+{
+    hbitmap_iter_init(hbi, bs->dirty_bitmap, 0);
+}
+
+void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
+                    int nr_sectors)
+{
+    hbitmap_set(bs->dirty_bitmap, cur_sector, nr_sectors);
+}
+
+void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector,
+                      int nr_sectors)
+{
+    hbitmap_reset(bs->dirty_bitmap, cur_sector, nr_sectors);
+}
+
+int64_t bdrv_get_dirty_count(BlockDriverState *bs)
+{
+    if (bs->dirty_bitmap) {
+        return hbitmap_count(bs->dirty_bitmap);
+    } else {
+        return 0;
+    }
+}
+
+void bdrv_set_in_use(BlockDriverState *bs, int in_use)
+{
+    assert(bs->in_use != in_use);
+    bs->in_use = in_use;
+}
+
+int bdrv_in_use(BlockDriverState *bs)
+{
+    return bs->in_use;
+}
+
+void bdrv_iostatus_enable(BlockDriverState *bs)
+{
+    bs->iostatus_enabled = true;
+    bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+}
+
+/* The I/O status is only enabled if the drive explicitly
+ * enables it _and_ the VM is configured to stop on errors */
+bool bdrv_iostatus_is_enabled(const BlockDriverState *bs)
+{
+    return (bs->iostatus_enabled &&
+           (bs->on_write_error == BLOCKDEV_ON_ERROR_ENOSPC ||
+            bs->on_write_error == BLOCKDEV_ON_ERROR_STOP   ||
+            bs->on_read_error == BLOCKDEV_ON_ERROR_STOP));
+}
+
+void bdrv_iostatus_disable(BlockDriverState *bs)
+{
+    bs->iostatus_enabled = false;
+}
+
+void bdrv_iostatus_reset(BlockDriverState *bs)
+{
+    if (bdrv_iostatus_is_enabled(bs)) {
+        bs->iostatus = BLOCK_DEVICE_IO_STATUS_OK;
+        if (bs->job) {
+            block_job_iostatus_reset(bs->job);
+        }
+    }
+}
+
+void bdrv_iostatus_set_err(BlockDriverState *bs, int error)
+{
+    assert(bdrv_iostatus_is_enabled(bs));
+    if (bs->iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
+        bs->iostatus = error == ENOSPC ? BLOCK_DEVICE_IO_STATUS_NOSPACE :
+                                         BLOCK_DEVICE_IO_STATUS_FAILED;
+    }
+}
+
+void
+bdrv_acct_start(BlockDriverState *bs, BlockAcctCookie *cookie, int64_t bytes,
+        enum BlockAcctType type)
+{
+    assert(type < BDRV_MAX_IOTYPE);
+
+    cookie->bytes = bytes;
+    cookie->start_time_ns = get_clock();
+    cookie->type = type;
+}
+
+void
+bdrv_acct_done(BlockDriverState *bs, BlockAcctCookie *cookie)
+{
+    assert(cookie->type < BDRV_MAX_IOTYPE);
+
+    bs->nr_bytes[cookie->type] += cookie->bytes;
+    bs->nr_ops[cookie->type]++;
+    bs->total_time_ns[cookie->type] += get_clock() - cookie->start_time_ns;
+}
+
+void bdrv_img_create(const char *filename, const char *fmt,
+                     const char *base_filename, const char *base_fmt,
+                     char *options, uint64_t img_size, int flags,
+                     Error **errp, bool quiet)
+{
+    QEMUOptionParameter *param = NULL, *create_options = NULL;
+    QEMUOptionParameter *backing_fmt, *backing_file, *size;
+    BlockDriverState *bs = NULL;
+    BlockDriver *drv, *proto_drv;
+    BlockDriver *backing_drv = NULL;
+    int ret = 0;
+
+    /* Find driver and parse its options */
+    drv = bdrv_find_format(fmt);
+    if (!drv) {
+        error_setg(errp, "Unknown file format '%s'", fmt);
+        return;
+    }
+
+    proto_drv = bdrv_find_protocol(filename, true);
+    if (!proto_drv) {
+        error_setg(errp, "Unknown protocol '%s'", filename);
+        return;
+    }
+
+    create_options = append_option_parameters(create_options,
+                                              drv->create_options);
+    create_options = append_option_parameters(create_options,
+                                              proto_drv->create_options);
+
+    /* Create parameter list with default values */
+    param = parse_option_parameters("", create_options, param);
+
+    set_option_parameter_int(param, BLOCK_OPT_SIZE, img_size);
+
+    /* Parse -o options */
+    if (options) {
+        param = parse_option_parameters(options, create_options, param);
+        if (param == NULL) {
+            error_setg(errp, "Invalid options for file format '%s'.", fmt);
+            goto out;
+        }
+    }
+
+    if (base_filename) {
+        if (set_option_parameter(param, BLOCK_OPT_BACKING_FILE,
+                                 base_filename)) {
+            error_setg(errp, "Backing file not supported for file format '%s'",
+                       fmt);
+            goto out;
+        }
+    }
+
+    if (base_fmt) {
+        if (set_option_parameter(param, BLOCK_OPT_BACKING_FMT, base_fmt)) {
+            error_setg(errp, "Backing file format not supported for file "
+                             "format '%s'", fmt);
+            goto out;
+        }
+    }
+
+    backing_file = get_option_parameter(param, BLOCK_OPT_BACKING_FILE);
+    if (backing_file && backing_file->value.s) {
+        if (!strcmp(filename, backing_file->value.s)) {
+            error_setg(errp, "Error: Trying to create an image with the "
+                             "same filename as the backing file");
+            goto out;
+        }
+    }
+
+    backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT);
+    if (backing_fmt && backing_fmt->value.s) {
+        backing_drv = bdrv_find_format(backing_fmt->value.s);
+        if (!backing_drv) {
+            error_setg(errp, "Unknown backing file format '%s'",
+                       backing_fmt->value.s);
+            goto out;
+        }
+    }
+
+    // The size for the image must always be specified, with one exception:
+    // If we are using a backing file, we can obtain the size from there
+    size = get_option_parameter(param, BLOCK_OPT_SIZE);
+    if (size && size->value.n == -1) {
+        if (backing_file && backing_file->value.s) {
+            uint64_t size;
+            char buf[32];
+            int back_flags;
+
+            /* backing files always opened read-only */
+            back_flags =
+                flags & ~(BDRV_O_RDWR | BDRV_O_SNAPSHOT | BDRV_O_NO_BACKING);
+
+            bs = bdrv_new("");
+
+            ret = bdrv_open(bs, backing_file->value.s, NULL, back_flags,
+                            backing_drv);
+            if (ret < 0) {
+                error_setg_errno(errp, -ret, "Could not open '%s'",
+                                 backing_file->value.s);
+                goto out;
+            }
+            bdrv_get_geometry(bs, &size);
+            size *= 512;
+
+            snprintf(buf, sizeof(buf), "%" PRId64, size);
+            set_option_parameter(param, BLOCK_OPT_SIZE, buf);
+        } else {
+            error_setg(errp, "Image creation needs a size parameter");
+            goto out;
+        }
+    }
+
+    if (!quiet) {
+        printf("Formatting '%s', fmt=%s ", filename, fmt);
+        print_option_parameters(param);
+        puts("");
+    }
+    ret = bdrv_create(drv, filename, param);
+    if (ret < 0) {
+        if (ret == -ENOTSUP) {
+            error_setg(errp,"Formatting or formatting option not supported for "
+                            "file format '%s'", fmt);
+        } else if (ret == -EFBIG) {
+            const char *cluster_size_hint = "";
+            if (get_option_parameter(create_options, BLOCK_OPT_CLUSTER_SIZE)) {
+                cluster_size_hint = " (try using a larger cluster size)";
+            }
+            error_setg(errp, "The image size is too large for file format '%s'%s",
+                       fmt, cluster_size_hint);
+        } else {
+            error_setg(errp, "%s: error while creating %s: %s", filename, fmt,
+                       strerror(-ret));
+        }
+    }
+
+out:
+    free_option_parameters(create_options);
+    free_option_parameters(param);
+
+    if (bs) {
+        bdrv_delete(bs);
+    }
+}
+
+AioContext *bdrv_get_aio_context(BlockDriverState *bs)
+{
+    /* Currently BlockDriverState always uses the main loop AioContext */
+    return qemu_get_aio_context();
+}
+
+void bdrv_add_before_write_notifier(BlockDriverState *bs,
+                                    NotifierWithReturn *notifier)
+{
+    notifier_with_return_list_add(&bs->before_write_notifiers, notifier);
+}
diff --git a/contrib/qemu/block/qcow.c b/contrib/qemu/block/qcow.c
new file mode 100644
index 000000000..5239bd68f
--- /dev/null
+++ b/contrib/qemu/block/qcow.c
@@ -0,0 +1,914 @@
+/*
+ * Block driver for the QCOW format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "qemu/module.h"
+#include <zlib.h>
+#include "qemu/aes.h"
+#include "migration/migration.h"
+
+/**************************************************************/
+/* QEMU COW block driver with compression and encryption support */
+
+#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
+#define QCOW_VERSION 1
+
+#define QCOW_CRYPT_NONE 0
+#define QCOW_CRYPT_AES  1
+
+#define QCOW_OFLAG_COMPRESSED (1LL << 63)
+
+typedef struct QCowHeader {
+    uint32_t magic;
+    uint32_t version;
+    uint64_t backing_file_offset;
+    uint32_t backing_file_size;
+    uint32_t mtime;
+    uint64_t size; /* in bytes */
+    uint8_t cluster_bits;
+    uint8_t l2_bits;
+    uint32_t crypt_method;
+    uint64_t l1_table_offset;
+} QCowHeader;
+
+#define L2_CACHE_SIZE 16
+
+typedef struct BDRVQcowState {
+    int cluster_bits;
+    int cluster_size;
+    int cluster_sectors;
+    int l2_bits;
+    int l2_size;
+    int l1_size;
+    uint64_t cluster_offset_mask;
+    uint64_t l1_table_offset;
+    uint64_t *l1_table;
+    uint64_t *l2_cache;
+    uint64_t l2_cache_offsets[L2_CACHE_SIZE];
+    uint32_t l2_cache_counts[L2_CACHE_SIZE];
+    uint8_t *cluster_cache;
+    uint8_t *cluster_data;
+    uint64_t cluster_cache_offset;
+    uint32_t crypt_method; /* current crypt method, 0 if no key yet */
+    uint32_t crypt_method_header;
+    AES_KEY aes_encrypt_key;
+    AES_KEY aes_decrypt_key;
+    CoMutex lock;
+    Error *migration_blocker;
+} BDRVQcowState;
+
+static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
+
+static int qcow_probe(const uint8_t *buf, int buf_size, const char *filename)
+{
+    const QCowHeader *cow_header = (const void *)buf;
+
+    if (buf_size >= sizeof(QCowHeader) &&
+        be32_to_cpu(cow_header->magic) == QCOW_MAGIC &&
+        be32_to_cpu(cow_header->version) == QCOW_VERSION)
+        return 100;
+    else
+        return 0;
+}
+
+static int qcow_open(BlockDriverState *bs, QDict *options, int flags)
+{
+    BDRVQcowState *s = bs->opaque;
+    int len, i, shift, ret;
+    QCowHeader header;
+
+    ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
+    if (ret < 0) {
+        goto fail;
+    }
+    be32_to_cpus(&header.magic);
+    be32_to_cpus(&header.version);
+    be64_to_cpus(&header.backing_file_offset);
+    be32_to_cpus(&header.backing_file_size);
+    be32_to_cpus(&header.mtime);
+    be64_to_cpus(&header.size);
+    be32_to_cpus(&header.crypt_method);
+    be64_to_cpus(&header.l1_table_offset);
+
+    if (header.magic != QCOW_MAGIC) {
+        ret = -EMEDIUMTYPE;
+        goto fail;
+    }
+    if (header.version != QCOW_VERSION) {
+        char version[64];
+        snprintf(version, sizeof(version), "QCOW version %d", header.version);
+        qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+            bs->device_name, "qcow", version);
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    if (header.size <= 1 || header.cluster_bits < 9) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    if (header.crypt_method > QCOW_CRYPT_AES) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    s->crypt_method_header = header.crypt_method;
+    if (s->crypt_method_header) {
+        bs->encrypted = 1;
+    }
+    s->cluster_bits = header.cluster_bits;
+    s->cluster_size = 1 << s->cluster_bits;
+    s->cluster_sectors = 1 << (s->cluster_bits - 9);
+    s->l2_bits = header.l2_bits;
+    s->l2_size = 1 << s->l2_bits;
+    bs->total_sectors = header.size / 512;
+    s->cluster_offset_mask = (1LL << (63 - s->cluster_bits)) - 1;
+
+    /* read the level 1 table */
+    shift = s->cluster_bits + s->l2_bits;
+    s->l1_size = (header.size + (1LL << shift) - 1) >> shift;
+
+    s->l1_table_offset = header.l1_table_offset;
+    s->l1_table = g_malloc(s->l1_size * sizeof(uint64_t));
+
+    ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
+               s->l1_size * sizeof(uint64_t));
+    if (ret < 0) {
+        goto fail;
+    }
+
+    for(i = 0;i < s->l1_size; i++) {
+        be64_to_cpus(&s->l1_table[i]);
+    }
+    /* alloc L2 cache */
+    s->l2_cache = g_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
+    s->cluster_cache = g_malloc(s->cluster_size);
+    s->cluster_data = g_malloc(s->cluster_size);
+    s->cluster_cache_offset = -1;
+
+    /* read the backing file name */
+    if (header.backing_file_offset != 0) {
+        len = header.backing_file_size;
+        if (len > 1023) {
+            len = 1023;
+        }
+        ret = bdrv_pread(bs->file, header.backing_file_offset,
+                   bs->backing_file, len);
+        if (ret < 0) {
+            goto fail;
+        }
+        bs->backing_file[len] = '\0';
+    }
+
+    /* Disable migration when qcow images are used */
+    error_set(&s->migration_blocker,
+              QERR_BLOCK_FORMAT_FEATURE_NOT_SUPPORTED,
+              "qcow", bs->device_name, "live migration");
+    migrate_add_blocker(s->migration_blocker);
+
+    qemu_co_mutex_init(&s->lock);
+    return 0;
+
+ fail:
+    g_free(s->l1_table);
+    g_free(s->l2_cache);
+    g_free(s->cluster_cache);
+    g_free(s->cluster_data);
+    return ret;
+}
+
+
+/* We have nothing to do for QCOW reopen, stubs just return
+ * success */
+static int qcow_reopen_prepare(BDRVReopenState *state,
+                               BlockReopenQueue *queue, Error **errp)
+{
+    return 0;
+}
+
+static int qcow_set_key(BlockDriverState *bs, const char *key)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint8_t keybuf[16];
+    int len, i;
+
+    memset(keybuf, 0, 16);
+    len = strlen(key);
+    if (len > 16)
+        len = 16;
+    /* XXX: we could compress the chars to 7 bits to increase
+       entropy */
+    for(i = 0;i < len;i++) {
+        keybuf[i] = key[i];
+    }
+    s->crypt_method = s->crypt_method_header;
+
+    if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0)
+        return -1;
+    if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0)
+        return -1;
+    return 0;
+}
+
+/* The crypt function is compatible with the linux cryptoloop
+   algorithm for < 4 GB images. NOTE: out_buf == in_buf is
+   supported */
+static void encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+                            uint8_t *out_buf, const uint8_t *in_buf,
+                            int nb_sectors, int enc,
+                            const AES_KEY *key)
+{
+    union {
+        uint64_t ll[2];
+        uint8_t b[16];
+    } ivec;
+    int i;
+
+    for(i = 0; i < nb_sectors; i++) {
+        ivec.ll[0] = cpu_to_le64(sector_num);
+        ivec.ll[1] = 0;
+        AES_cbc_encrypt(in_buf, out_buf, 512, key,
+                        ivec.b, enc);
+        sector_num++;
+        in_buf += 512;
+        out_buf += 512;
+    }
+}
+
+/* 'allocate' is:
+ *
+ * 0 to not allocate.
+ *
+ * 1 to allocate a normal cluster (for sector indexes 'n_start' to
+ * 'n_end')
+ *
+ * 2 to allocate a compressed cluster of size
+ * 'compressed_size'. 'compressed_size' must be > 0 and <
+ * cluster_size
+ *
+ * return 0 if not allocated.
+ */
+static uint64_t get_cluster_offset(BlockDriverState *bs,
+                                   uint64_t offset, int allocate,
+                                   int compressed_size,
+                                   int n_start, int n_end)
+{
+    BDRVQcowState *s = bs->opaque;
+    int min_index, i, j, l1_index, l2_index;
+    uint64_t l2_offset, *l2_table, cluster_offset, tmp;
+    uint32_t min_count;
+    int new_l2_table;
+
+    l1_index = offset >> (s->l2_bits + s->cluster_bits);
+    l2_offset = s->l1_table[l1_index];
+    new_l2_table = 0;
+    if (!l2_offset) {
+        if (!allocate)
+            return 0;
+        /* allocate a new l2 entry */
+        l2_offset = bdrv_getlength(bs->file);
+        /* round to cluster size */
+        l2_offset = (l2_offset + s->cluster_size - 1) & ~(s->cluster_size - 1);
+        /* update the L1 entry */
+        s->l1_table[l1_index] = l2_offset;
+        tmp = cpu_to_be64(l2_offset);
+        if (bdrv_pwrite_sync(bs->file,
+                s->l1_table_offset + l1_index * sizeof(tmp),
+                &tmp, sizeof(tmp)) < 0)
+            return 0;
+        new_l2_table = 1;
+    }
+    for(i = 0; i < L2_CACHE_SIZE; i++) {
+        if (l2_offset == s->l2_cache_offsets[i]) {
+            /* increment the hit count */
+            if (++s->l2_cache_counts[i] == 0xffffffff) {
+                for(j = 0; j < L2_CACHE_SIZE; j++) {
+                    s->l2_cache_counts[j] >>= 1;
+                }
+            }
+            l2_table = s->l2_cache + (i << s->l2_bits);
+            goto found;
+        }
+    }
+    /* not found: load a new entry in the least used one */
+    min_index = 0;
+    min_count = 0xffffffff;
+    for(i = 0; i < L2_CACHE_SIZE; i++) {
+        if (s->l2_cache_counts[i] < min_count) {
+            min_count = s->l2_cache_counts[i];
+            min_index = i;
+        }
+    }
+    l2_table = s->l2_cache + (min_index << s->l2_bits);
+    if (new_l2_table) {
+        memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
+        if (bdrv_pwrite_sync(bs->file, l2_offset, l2_table,
+                s->l2_size * sizeof(uint64_t)) < 0)
+            return 0;
+    } else {
+        if (bdrv_pread(bs->file, l2_offset, l2_table, s->l2_size * sizeof(uint64_t)) !=
+            s->l2_size * sizeof(uint64_t))
+            return 0;
+    }
+    s->l2_cache_offsets[min_index] = l2_offset;
+    s->l2_cache_counts[min_index] = 1;
+ found:
+    l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+    cluster_offset = be64_to_cpu(l2_table[l2_index]);
+    if (!cluster_offset ||
+        ((cluster_offset & QCOW_OFLAG_COMPRESSED) && allocate == 1)) {
+        if (!allocate)
+            return 0;
+        /* allocate a new cluster */
+        if ((cluster_offset & QCOW_OFLAG_COMPRESSED) &&
+            (n_end - n_start) < s->cluster_sectors) {
+            /* if the cluster is already compressed, we must
+               decompress it in the case it is not completely
+               overwritten */
+            if (decompress_cluster(bs, cluster_offset) < 0)
+                return 0;
+            cluster_offset = bdrv_getlength(bs->file);
+            cluster_offset = (cluster_offset + s->cluster_size - 1) &
+                ~(s->cluster_size - 1);
+            /* write the cluster content */
+            if (bdrv_pwrite(bs->file, cluster_offset, s->cluster_cache, s->cluster_size) !=
+                s->cluster_size)
+                return -1;
+        } else {
+            cluster_offset = bdrv_getlength(bs->file);
+            if (allocate == 1) {
+                /* round to cluster size */
+                cluster_offset = (cluster_offset + s->cluster_size - 1) &
+                    ~(s->cluster_size - 1);
+                bdrv_truncate(bs->file, cluster_offset + s->cluster_size);
+                /* if encrypted, we must initialize the cluster
+                   content which won't be written */
+                if (s->crypt_method &&
+                    (n_end - n_start) < s->cluster_sectors) {
+                    uint64_t start_sect;
+                    start_sect = (offset & ~(s->cluster_size - 1)) >> 9;
+                    memset(s->cluster_data + 512, 0x00, 512);
+                    for(i = 0; i < s->cluster_sectors; i++) {
+                        if (i < n_start || i >= n_end) {
+                            encrypt_sectors(s, start_sect + i,
+                                            s->cluster_data,
+                                            s->cluster_data + 512, 1, 1,
+                                            &s->aes_encrypt_key);
+                            if (bdrv_pwrite(bs->file, cluster_offset + i * 512,
+                                            s->cluster_data, 512) != 512)
+                                return -1;
+                        }
+                    }
+                }
+            } else if (allocate == 2) {
+                cluster_offset |= QCOW_OFLAG_COMPRESSED |
+                    (uint64_t)compressed_size << (63 - s->cluster_bits);
+            }
+        }
+        /* update L2 table */
+        tmp = cpu_to_be64(cluster_offset);
+        l2_table[l2_index] = tmp;
+        if (bdrv_pwrite_sync(bs->file, l2_offset + l2_index * sizeof(tmp),
+                &tmp, sizeof(tmp)) < 0)
+            return 0;
+    }
+    return cluster_offset;
+}
+
+static int coroutine_fn qcow_co_is_allocated(BlockDriverState *bs,
+        int64_t sector_num, int nb_sectors, int *pnum)
+{
+    BDRVQcowState *s = bs->opaque;
+    int index_in_cluster, n;
+    uint64_t cluster_offset;
+
+    qemu_co_mutex_lock(&s->lock);
+    cluster_offset = get_cluster_offset(bs, sector_num << 9, 0, 0, 0, 0);
+    qemu_co_mutex_unlock(&s->lock);
+    index_in_cluster = sector_num & (s->cluster_sectors - 1);
+    n = s->cluster_sectors - index_in_cluster;
+    if (n > nb_sectors)
+        n = nb_sectors;
+    *pnum = n;
+    return (cluster_offset != 0);
+}
+
+static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
+                             const uint8_t *buf, int buf_size)
+{
+    z_stream strm1, *strm = &strm1;
+    int ret, out_len;
+
+    memset(strm, 0, sizeof(*strm));
+
+    strm->next_in = (uint8_t *)buf;
+    strm->avail_in = buf_size;
+    strm->next_out = out_buf;
+    strm->avail_out = out_buf_size;
+
+    ret = inflateInit2(strm, -12);
+    if (ret != Z_OK)
+        return -1;
+    ret = inflate(strm, Z_FINISH);
+    out_len = strm->next_out - out_buf;
+    if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
+        out_len != out_buf_size) {
+        inflateEnd(strm);
+        return -1;
+    }
+    inflateEnd(strm);
+    return 0;
+}
+
+static int decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret, csize;
+    uint64_t coffset;
+
+    coffset = cluster_offset & s->cluster_offset_mask;
+    if (s->cluster_cache_offset != coffset) {
+        csize = cluster_offset >> (63 - s->cluster_bits);
+        csize &= (s->cluster_size - 1);
+        ret = bdrv_pread(bs->file, coffset, s->cluster_data, csize);
+        if (ret != csize)
+            return -1;
+        if (decompress_buffer(s->cluster_cache, s->cluster_size,
+                              s->cluster_data, csize) < 0) {
+            return -1;
+        }
+        s->cluster_cache_offset = coffset;
+    }
+    return 0;
+}
+
+static coroutine_fn int qcow_co_readv(BlockDriverState *bs, int64_t sector_num,
+                         int nb_sectors, QEMUIOVector *qiov)
+{
+    BDRVQcowState *s = bs->opaque;
+    int index_in_cluster;
+    int ret = 0, n;
+    uint64_t cluster_offset;
+    struct iovec hd_iov;
+    QEMUIOVector hd_qiov;
+    uint8_t *buf;
+    void *orig_buf;
+
+    if (qiov->niov > 1) {
+        buf = orig_buf = qemu_blockalign(bs, qiov->size);
+    } else {
+        orig_buf = NULL;
+        buf = (uint8_t *)qiov->iov->iov_base;
+    }
+
+    qemu_co_mutex_lock(&s->lock);
+
+    while (nb_sectors != 0) {
+        /* prepare next request */
+        cluster_offset = get_cluster_offset(bs, sector_num << 9,
+                                                 0, 0, 0, 0);
+        index_in_cluster = sector_num & (s->cluster_sectors - 1);
+        n = s->cluster_sectors - index_in_cluster;
+        if (n > nb_sectors) {
+            n = nb_sectors;
+        }
+
+        if (!cluster_offset) {
+            if (bs->backing_hd) {
+                /* read from the base image */
+                hd_iov.iov_base = (void *)buf;
+                hd_iov.iov_len = n * 512;
+                qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
+                qemu_co_mutex_unlock(&s->lock);
+                ret = bdrv_co_readv(bs->backing_hd, sector_num,
+                                    n, &hd_qiov);
+                qemu_co_mutex_lock(&s->lock);
+                if (ret < 0) {
+                    goto fail;
+                }
+            } else {
+                /* Note: in this case, no need to wait */
+                memset(buf, 0, 512 * n);
+            }
+        } else if (cluster_offset & QCOW_OFLAG_COMPRESSED) {
+            /* add AIO support for compressed blocks ? */
+            if (decompress_cluster(bs, cluster_offset) < 0) {
+                goto fail;
+            }
+            memcpy(buf,
+                   s->cluster_cache + index_in_cluster * 512, 512 * n);
+        } else {
+            if ((cluster_offset & 511) != 0) {
+                goto fail;
+            }
+            hd_iov.iov_base = (void *)buf;
+            hd_iov.iov_len = n * 512;
+            qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
+            qemu_co_mutex_unlock(&s->lock);
+            ret = bdrv_co_readv(bs->file,
+                                (cluster_offset >> 9) + index_in_cluster,
+                                n, &hd_qiov);
+            qemu_co_mutex_lock(&s->lock);
+            if (ret < 0) {
+                break;
+            }
+            if (s->crypt_method) {
+                encrypt_sectors(s, sector_num, buf, buf,
+                                n, 0,
+                                &s->aes_decrypt_key);
+            }
+        }
+        ret = 0;
+
+        nb_sectors -= n;
+        sector_num += n;
+        buf += n * 512;
+    }
+
+done:
+    qemu_co_mutex_unlock(&s->lock);
+
+    if (qiov->niov > 1) {
+        qemu_iovec_from_buf(qiov, 0, orig_buf, qiov->size);
+        qemu_vfree(orig_buf);
+    }
+
+    return ret;
+
+fail:
+    ret = -EIO;
+    goto done;
+}
+
+static coroutine_fn int qcow_co_writev(BlockDriverState *bs, int64_t sector_num,
+                          int nb_sectors, QEMUIOVector *qiov)
+{
+    BDRVQcowState *s = bs->opaque;
+    int index_in_cluster;
+    uint64_t cluster_offset;
+    const uint8_t *src_buf;
+    int ret = 0, n;
+    uint8_t *cluster_data = NULL;
+    struct iovec hd_iov;
+    QEMUIOVector hd_qiov;
+    uint8_t *buf;
+    void *orig_buf;
+
+    s->cluster_cache_offset = -1; /* disable compressed cache */
+
+    if (qiov->niov > 1) {
+        buf = orig_buf = qemu_blockalign(bs, qiov->size);
+        qemu_iovec_to_buf(qiov, 0, buf, qiov->size);
+    } else {
+        orig_buf = NULL;
+        buf = (uint8_t *)qiov->iov->iov_base;
+    }
+
+    qemu_co_mutex_lock(&s->lock);
+
+    while (nb_sectors != 0) {
+
+        index_in_cluster = sector_num & (s->cluster_sectors - 1);
+        n = s->cluster_sectors - index_in_cluster;
+        if (n > nb_sectors) {
+            n = nb_sectors;
+        }
+        cluster_offset = get_cluster_offset(bs, sector_num << 9, 1, 0,
+                                            index_in_cluster,
+                                            index_in_cluster + n);
+        if (!cluster_offset || (cluster_offset & 511) != 0) {
+            ret = -EIO;
+            break;
+        }
+        if (s->crypt_method) {
+            if (!cluster_data) {
+                cluster_data = g_malloc0(s->cluster_size);
+            }
+            encrypt_sectors(s, sector_num, cluster_data, buf,
+                            n, 1, &s->aes_encrypt_key);
+            src_buf = cluster_data;
+        } else {
+            src_buf = buf;
+        }
+
+        hd_iov.iov_base = (void *)src_buf;
+        hd_iov.iov_len = n * 512;
+        qemu_iovec_init_external(&hd_qiov, &hd_iov, 1);
+        qemu_co_mutex_unlock(&s->lock);
+        ret = bdrv_co_writev(bs->file,
+                             (cluster_offset >> 9) + index_in_cluster,
+                             n, &hd_qiov);
+        qemu_co_mutex_lock(&s->lock);
+        if (ret < 0) {
+            break;
+        }
+        ret = 0;
+
+        nb_sectors -= n;
+        sector_num += n;
+        buf += n * 512;
+    }
+    qemu_co_mutex_unlock(&s->lock);
+
+    if (qiov->niov > 1) {
+        qemu_vfree(orig_buf);
+    }
+    g_free(cluster_data);
+
+    return ret;
+}
+
+static void qcow_close(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+
+    g_free(s->l1_table);
+    g_free(s->l2_cache);
+    g_free(s->cluster_cache);
+    g_free(s->cluster_data);
+
+    migrate_del_blocker(s->migration_blocker);
+    error_free(s->migration_blocker);
+}
+
+static int qcow_create(const char *filename, QEMUOptionParameter *options)
+{
+    int header_size, backing_filename_len, l1_size, shift, i;
+    QCowHeader header;
+    uint8_t *tmp;
+    int64_t total_size = 0;
+    const char *backing_file = NULL;
+    int flags = 0;
+    int ret;
+    BlockDriverState *qcow_bs;
+
+    /* Read out options */
+    while (options && options->name) {
+        if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+            total_size = options->value.n / 512;
+        } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
+            backing_file = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
+            flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
+        }
+        options++;
+    }
+
+    ret = bdrv_create_file(filename, options);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = bdrv_file_open(&qcow_bs, filename, NULL, BDRV_O_RDWR);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = bdrv_truncate(qcow_bs, 0);
+    if (ret < 0) {
+        goto exit;
+    }
+
+    memset(&header, 0, sizeof(header));
+    header.magic = cpu_to_be32(QCOW_MAGIC);
+    header.version = cpu_to_be32(QCOW_VERSION);
+    header.size = cpu_to_be64(total_size * 512);
+    header_size = sizeof(header);
+    backing_filename_len = 0;
+    if (backing_file) {
+        if (strcmp(backing_file, "fat:")) {
+            header.backing_file_offset = cpu_to_be64(header_size);
+            backing_filename_len = strlen(backing_file);
+            header.backing_file_size = cpu_to_be32(backing_filename_len);
+            header_size += backing_filename_len;
+        } else {
+            /* special backing file for vvfat */
+            backing_file = NULL;
+        }
+        header.cluster_bits = 9; /* 512 byte cluster to avoid copying
+                                    unmodifyed sectors */
+        header.l2_bits = 12; /* 32 KB L2 tables */
+    } else {
+        header.cluster_bits = 12; /* 4 KB clusters */
+        header.l2_bits = 9; /* 4 KB L2 tables */
+    }
+    header_size = (header_size + 7) & ~7;
+    shift = header.cluster_bits + header.l2_bits;
+    l1_size = ((total_size * 512) + (1LL << shift) - 1) >> shift;
+
+    header.l1_table_offset = cpu_to_be64(header_size);
+    if (flags & BLOCK_FLAG_ENCRYPT) {
+        header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
+    } else {
+        header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
+    }
+
+    /* write all the data */
+    ret = bdrv_pwrite(qcow_bs, 0, &header, sizeof(header));
+    if (ret != sizeof(header)) {
+        goto exit;
+    }
+
+    if (backing_file) {
+        ret = bdrv_pwrite(qcow_bs, sizeof(header),
+            backing_file, backing_filename_len);
+        if (ret != backing_filename_len) {
+            goto exit;
+        }
+    }
+
+    tmp = g_malloc0(BDRV_SECTOR_SIZE);
+    for (i = 0; i < ((sizeof(uint64_t)*l1_size + BDRV_SECTOR_SIZE - 1)/
+        BDRV_SECTOR_SIZE); i++) {
+        ret = bdrv_pwrite(qcow_bs, header_size +
+            BDRV_SECTOR_SIZE*i, tmp, BDRV_SECTOR_SIZE);
+        if (ret != BDRV_SECTOR_SIZE) {
+            g_free(tmp);
+            goto exit;
+        }
+    }
+
+    g_free(tmp);
+    ret = 0;
+exit:
+    bdrv_delete(qcow_bs);
+    return ret;
+}
+
+static int qcow_make_empty(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint32_t l1_length = s->l1_size * sizeof(uint64_t);
+    int ret;
+
+    memset(s->l1_table, 0, l1_length);
+    if (bdrv_pwrite_sync(bs->file, s->l1_table_offset, s->l1_table,
+            l1_length) < 0)
+        return -1;
+    ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
+    if (ret < 0)
+        return ret;
+
+    memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
+    memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
+    memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
+
+    return 0;
+}
+
+/* XXX: put compressed sectors first, then all the cluster aligned
+   tables to avoid losing bytes in alignment */
+static int qcow_write_compressed(BlockDriverState *bs, int64_t sector_num,
+                                 const uint8_t *buf, int nb_sectors)
+{
+    BDRVQcowState *s = bs->opaque;
+    z_stream strm;
+    int ret, out_len;
+    uint8_t *out_buf;
+    uint64_t cluster_offset;
+
+    if (nb_sectors != s->cluster_sectors) {
+        ret = -EINVAL;
+
+        /* Zero-pad last write if image size is not cluster aligned */
+        if (sector_num + nb_sectors == bs->total_sectors &&
+            nb_sectors < s->cluster_sectors) {
+            uint8_t *pad_buf = qemu_blockalign(bs, s->cluster_size);
+            memset(pad_buf, 0, s->cluster_size);
+            memcpy(pad_buf, buf, nb_sectors * BDRV_SECTOR_SIZE);
+            ret = qcow_write_compressed(bs, sector_num,
+                                        pad_buf, s->cluster_sectors);
+            qemu_vfree(pad_buf);
+        }
+        return ret;
+    }
+
+    out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128);
+
+    /* best compression, small window, no zlib header */
+    memset(&strm, 0, sizeof(strm));
+    ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,
+                       Z_DEFLATED, -12,
+                       9, Z_DEFAULT_STRATEGY);
+    if (ret != 0) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    strm.avail_in = s->cluster_size;
+    strm.next_in = (uint8_t *)buf;
+    strm.avail_out = s->cluster_size;
+    strm.next_out = out_buf;
+
+    ret = deflate(&strm, Z_FINISH);
+    if (ret != Z_STREAM_END && ret != Z_OK) {
+        deflateEnd(&strm);
+        ret = -EINVAL;
+        goto fail;
+    }
+    out_len = strm.next_out - out_buf;
+
+    deflateEnd(&strm);
+
+    if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
+        /* could not compress: write normal cluster */
+        ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors);
+        if (ret < 0) {
+            goto fail;
+        }
+    } else {
+        cluster_offset = get_cluster_offset(bs, sector_num << 9, 2,
+                                            out_len, 0, 0);
+        if (cluster_offset == 0) {
+            ret = -EIO;
+            goto fail;
+        }
+
+        cluster_offset &= s->cluster_offset_mask;
+        ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    ret = 0;
+fail:
+    g_free(out_buf);
+    return ret;
+}
+
+static int qcow_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+    BDRVQcowState *s = bs->opaque;
+    bdi->cluster_size = s->cluster_size;
+    return 0;
+}
+
+
+static QEMUOptionParameter qcow_create_options[] = {
+    {
+        .name = BLOCK_OPT_SIZE,
+        .type = OPT_SIZE,
+        .help = "Virtual disk size"
+    },
+    {
+        .name = BLOCK_OPT_BACKING_FILE,
+        .type = OPT_STRING,
+        .help = "File name of a base image"
+    },
+    {
+        .name = BLOCK_OPT_ENCRYPT,
+        .type = OPT_FLAG,
+        .help = "Encrypt the image"
+    },
+    { NULL }
+};
+
+static BlockDriver bdrv_qcow = {
+    .format_name	= "qcow",
+    .instance_size	= sizeof(BDRVQcowState),
+    .bdrv_probe		= qcow_probe,
+    .bdrv_open		= qcow_open,
+    .bdrv_close		= qcow_close,
+    .bdrv_reopen_prepare = qcow_reopen_prepare,
+    .bdrv_create	= qcow_create,
+    .bdrv_has_zero_init     = bdrv_has_zero_init_1,
+
+    .bdrv_co_readv          = qcow_co_readv,
+    .bdrv_co_writev         = qcow_co_writev,
+    .bdrv_co_is_allocated   = qcow_co_is_allocated,
+
+    .bdrv_set_key           = qcow_set_key,
+    .bdrv_make_empty        = qcow_make_empty,
+    .bdrv_write_compressed  = qcow_write_compressed,
+    .bdrv_get_info          = qcow_get_info,
+
+    .create_options = qcow_create_options,
+};
+
+static void bdrv_qcow_init(void)
+{
+    bdrv_register(&bdrv_qcow);
+}
+
+block_init(bdrv_qcow_init);
diff --git a/contrib/qemu/block/qcow2-cache.c b/contrib/qemu/block/qcow2-cache.c
new file mode 100644
index 000000000..2f3114ecc
--- /dev/null
+++ b/contrib/qemu/block/qcow2-cache.c
@@ -0,0 +1,323 @@
+/*
+ * L2/refcount table cache for the QCOW2 format
+ *
+ * Copyright (c) 2010 Kevin Wolf <kwolf@redhat.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "block/block_int.h"
+#include "qemu-common.h"
+#include "qcow2.h"
+#include "trace.h"
+
+typedef struct Qcow2CachedTable {
+    void*   table;
+    int64_t offset;
+    bool    dirty;
+    int     cache_hits;
+    int     ref;
+} Qcow2CachedTable;
+
+struct Qcow2Cache {
+    Qcow2CachedTable*       entries;
+    struct Qcow2Cache*      depends;
+    int                     size;
+    bool                    depends_on_flush;
+};
+
+Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2Cache *c;
+    int i;
+
+    c = g_malloc0(sizeof(*c));
+    c->size = num_tables;
+    c->entries = g_malloc0(sizeof(*c->entries) * num_tables);
+
+    for (i = 0; i < c->size; i++) {
+        c->entries[i].table = qemu_blockalign(bs, s->cluster_size);
+    }
+
+    return c;
+}
+
+int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c)
+{
+    int i;
+
+    for (i = 0; i < c->size; i++) {
+        assert(c->entries[i].ref == 0);
+        qemu_vfree(c->entries[i].table);
+    }
+
+    g_free(c->entries);
+    g_free(c);
+
+    return 0;
+}
+
+static int qcow2_cache_flush_dependency(BlockDriverState *bs, Qcow2Cache *c)
+{
+    int ret;
+
+    ret = qcow2_cache_flush(bs, c->depends);
+    if (ret < 0) {
+        return ret;
+    }
+
+    c->depends = NULL;
+    c->depends_on_flush = false;
+
+    return 0;
+}
+
+static int qcow2_cache_entry_flush(BlockDriverState *bs, Qcow2Cache *c, int i)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret = 0;
+
+    if (!c->entries[i].dirty || !c->entries[i].offset) {
+        return 0;
+    }
+
+    trace_qcow2_cache_entry_flush(qemu_coroutine_self(),
+                                  c == s->l2_table_cache, i);
+
+    if (c->depends) {
+        ret = qcow2_cache_flush_dependency(bs, c);
+    } else if (c->depends_on_flush) {
+        ret = bdrv_flush(bs->file);
+        if (ret >= 0) {
+            c->depends_on_flush = false;
+        }
+    }
+
+    if (ret < 0) {
+        return ret;
+    }
+
+    if (c == s->refcount_block_cache) {
+        BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_UPDATE_PART);
+    } else if (c == s->l2_table_cache) {
+        BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE);
+    }
+
+    ret = bdrv_pwrite(bs->file, c->entries[i].offset, c->entries[i].table,
+        s->cluster_size);
+    if (ret < 0) {
+        return ret;
+    }
+
+    c->entries[i].dirty = false;
+
+    return 0;
+}
+
+int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c)
+{
+    BDRVQcowState *s = bs->opaque;
+    int result = 0;
+    int ret;
+    int i;
+
+    trace_qcow2_cache_flush(qemu_coroutine_self(), c == s->l2_table_cache);
+
+    for (i = 0; i < c->size; i++) {
+        ret = qcow2_cache_entry_flush(bs, c, i);
+        if (ret < 0 && result != -ENOSPC) {
+            result = ret;
+        }
+    }
+
+    if (result == 0) {
+        ret = bdrv_flush(bs->file);
+        if (ret < 0) {
+            result = ret;
+        }
+    }
+
+    return result;
+}
+
+int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
+    Qcow2Cache *dependency)
+{
+    int ret;
+
+    if (dependency->depends) {
+        ret = qcow2_cache_flush_dependency(bs, dependency);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    if (c->depends && (c->depends != dependency)) {
+        ret = qcow2_cache_flush_dependency(bs, c);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    c->depends = dependency;
+    return 0;
+}
+
+void qcow2_cache_depends_on_flush(Qcow2Cache *c)
+{
+    c->depends_on_flush = true;
+}
+
+static int qcow2_cache_find_entry_to_replace(Qcow2Cache *c)
+{
+    int i;
+    int min_count = INT_MAX;
+    int min_index = -1;
+
+
+    for (i = 0; i < c->size; i++) {
+        if (c->entries[i].ref) {
+            continue;
+        }
+
+        if (c->entries[i].cache_hits < min_count) {
+            min_index = i;
+            min_count = c->entries[i].cache_hits;
+        }
+
+        /* Give newer hits priority */
+        /* TODO Check how to optimize the replacement strategy */
+        c->entries[i].cache_hits /= 2;
+    }
+
+    if (min_index == -1) {
+        /* This can't happen in current synchronous code, but leave the check
+         * here as a reminder for whoever starts using AIO with the cache */
+        abort();
+    }
+    return min_index;
+}
+
+static int qcow2_cache_do_get(BlockDriverState *bs, Qcow2Cache *c,
+    uint64_t offset, void **table, bool read_from_disk)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i;
+    int ret;
+
+    trace_qcow2_cache_get(qemu_coroutine_self(), c == s->l2_table_cache,
+                          offset, read_from_disk);
+
+    /* Check if the table is already cached */
+    for (i = 0; i < c->size; i++) {
+        if (c->entries[i].offset == offset) {
+            goto found;
+        }
+    }
+
+    /* If not, write a table back and replace it */
+    i = qcow2_cache_find_entry_to_replace(c);
+    trace_qcow2_cache_get_replace_entry(qemu_coroutine_self(),
+                                        c == s->l2_table_cache, i);
+    if (i < 0) {
+        return i;
+    }
+
+    ret = qcow2_cache_entry_flush(bs, c, i);
+    if (ret < 0) {
+        return ret;
+    }
+
+    trace_qcow2_cache_get_read(qemu_coroutine_self(),
+                               c == s->l2_table_cache, i);
+    c->entries[i].offset = 0;
+    if (read_from_disk) {
+        if (c == s->l2_table_cache) {
+            BLKDBG_EVENT(bs->file, BLKDBG_L2_LOAD);
+        }
+
+        ret = bdrv_pread(bs->file, offset, c->entries[i].table, s->cluster_size);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    /* Give the table some hits for the start so that it won't be replaced
+     * immediately. The number 32 is completely arbitrary. */
+    c->entries[i].cache_hits = 32;
+    c->entries[i].offset = offset;
+
+    /* And return the right table */
+found:
+    c->entries[i].cache_hits++;
+    c->entries[i].ref++;
+    *table = c->entries[i].table;
+
+    trace_qcow2_cache_get_done(qemu_coroutine_self(),
+                               c == s->l2_table_cache, i);
+
+    return 0;
+}
+
+int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table)
+{
+    return qcow2_cache_do_get(bs, c, offset, table, true);
+}
+
+int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table)
+{
+    return qcow2_cache_do_get(bs, c, offset, table, false);
+}
+
+int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table)
+{
+    int i;
+
+    for (i = 0; i < c->size; i++) {
+        if (c->entries[i].table == *table) {
+            goto found;
+        }
+    }
+    return -ENOENT;
+
+found:
+    c->entries[i].ref--;
+    *table = NULL;
+
+    assert(c->entries[i].ref >= 0);
+    return 0;
+}
+
+void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table)
+{
+    int i;
+
+    for (i = 0; i < c->size; i++) {
+        if (c->entries[i].table == table) {
+            goto found;
+        }
+    }
+    abort();
+
+found:
+    c->entries[i].dirty = true;
+}
diff --git a/contrib/qemu/block/qcow2-cluster.c b/contrib/qemu/block/qcow2-cluster.c
new file mode 100644
index 000000000..cca76d4fc
--- /dev/null
+++ b/contrib/qemu/block/qcow2-cluster.c
@@ -0,0 +1,1478 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <zlib.h>
+
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "block/qcow2.h"
+#include "trace.h"
+
+int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
+                        bool exact_size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int new_l1_size2, ret, i;
+    uint64_t *new_l1_table;
+    int64_t new_l1_table_offset, new_l1_size;
+    uint8_t data[12];
+
+    if (min_size <= s->l1_size)
+        return 0;
+
+    if (exact_size) {
+        new_l1_size = min_size;
+    } else {
+        /* Bump size up to reduce the number of times we have to grow */
+        new_l1_size = s->l1_size;
+        if (new_l1_size == 0) {
+            new_l1_size = 1;
+        }
+        while (min_size > new_l1_size) {
+            new_l1_size = (new_l1_size * 3 + 1) / 2;
+        }
+    }
+
+    if (new_l1_size > INT_MAX) {
+        return -EFBIG;
+    }
+
+#ifdef DEBUG_ALLOC2
+    fprintf(stderr, "grow l1_table from %d to %" PRId64 "\n",
+            s->l1_size, new_l1_size);
+#endif
+
+    new_l1_size2 = sizeof(uint64_t) * new_l1_size;
+    new_l1_table = g_malloc0(align_offset(new_l1_size2, 512));
+    memcpy(new_l1_table, s->l1_table, s->l1_size * sizeof(uint64_t));
+
+    /* write new table (align to cluster) */
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ALLOC_TABLE);
+    new_l1_table_offset = qcow2_alloc_clusters(bs, new_l1_size2);
+    if (new_l1_table_offset < 0) {
+        g_free(new_l1_table);
+        return new_l1_table_offset;
+    }
+
+    ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_WRITE_TABLE);
+    for(i = 0; i < s->l1_size; i++)
+        new_l1_table[i] = cpu_to_be64(new_l1_table[i]);
+    ret = bdrv_pwrite_sync(bs->file, new_l1_table_offset, new_l1_table, new_l1_size2);
+    if (ret < 0)
+        goto fail;
+    for(i = 0; i < s->l1_size; i++)
+        new_l1_table[i] = be64_to_cpu(new_l1_table[i]);
+
+    /* set new table */
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_GROW_ACTIVATE_TABLE);
+    cpu_to_be32w((uint32_t*)data, new_l1_size);
+    cpu_to_be64wu((uint64_t*)(data + 4), new_l1_table_offset);
+    ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, l1_size), data,sizeof(data));
+    if (ret < 0) {
+        goto fail;
+    }
+    g_free(s->l1_table);
+    qcow2_free_clusters(bs, s->l1_table_offset, s->l1_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_OTHER);
+    s->l1_table_offset = new_l1_table_offset;
+    s->l1_table = new_l1_table;
+    s->l1_size = new_l1_size;
+    return 0;
+ fail:
+    g_free(new_l1_table);
+    qcow2_free_clusters(bs, new_l1_table_offset, new_l1_size2,
+                        QCOW2_DISCARD_OTHER);
+    return ret;
+}
+
+/*
+ * l2_load
+ *
+ * Loads a L2 table into memory. If the table is in the cache, the cache
+ * is used; otherwise the L2 table is loaded from the image file.
+ *
+ * Returns a pointer to the L2 table on success, or NULL if the read from
+ * the image file failed.
+ */
+
+static int l2_load(BlockDriverState *bs, uint64_t l2_offset,
+    uint64_t **l2_table)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret;
+
+    ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset, (void**) l2_table);
+
+    return ret;
+}
+
+/*
+ * Writes one sector of the L1 table to the disk (can't update single entries
+ * and we really don't want bdrv_pread to perform a read-modify-write)
+ */
+#define L1_ENTRIES_PER_SECTOR (512 / 8)
+static int write_l1_entry(BlockDriverState *bs, int l1_index)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t buf[L1_ENTRIES_PER_SECTOR];
+    int l1_start_index;
+    int i, ret;
+
+    l1_start_index = l1_index & ~(L1_ENTRIES_PER_SECTOR - 1);
+    for (i = 0; i < L1_ENTRIES_PER_SECTOR; i++) {
+        buf[i] = cpu_to_be64(s->l1_table[l1_start_index + i]);
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_L1_UPDATE);
+    ret = bdrv_pwrite_sync(bs->file, s->l1_table_offset + 8 * l1_start_index,
+        buf, sizeof(buf));
+    if (ret < 0) {
+        return ret;
+    }
+
+    return 0;
+}
+
+/*
+ * l2_allocate
+ *
+ * Allocate a new l2 entry in the file. If l1_index points to an already
+ * used entry in the L2 table (i.e. we are doing a copy on write for the L2
+ * table) copy the contents of the old L2 table into the newly allocated one.
+ * Otherwise the new table is initialized with zeros.
+ *
+ */
+
+static int l2_allocate(BlockDriverState *bs, int l1_index, uint64_t **table)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t old_l2_offset;
+    uint64_t *l2_table;
+    int64_t l2_offset;
+    int ret;
+
+    old_l2_offset = s->l1_table[l1_index];
+
+    trace_qcow2_l2_allocate(bs, l1_index);
+
+    /* allocate a new l2 entry */
+
+    l2_offset = qcow2_alloc_clusters(bs, s->l2_size * sizeof(uint64_t));
+    if (l2_offset < 0) {
+        return l2_offset;
+    }
+
+    ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* allocate a new entry in the l2 cache */
+
+    trace_qcow2_l2_allocate_get_empty(bs, l1_index);
+    ret = qcow2_cache_get_empty(bs, s->l2_table_cache, l2_offset, (void**) table);
+    if (ret < 0) {
+        return ret;
+    }
+
+    l2_table = *table;
+
+    if ((old_l2_offset & L1E_OFFSET_MASK) == 0) {
+        /* if there was no old l2 table, clear the new table */
+        memset(l2_table, 0, s->l2_size * sizeof(uint64_t));
+    } else {
+        uint64_t* old_table;
+
+        /* if there was an old l2 table, read it from the disk */
+        BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_COW_READ);
+        ret = qcow2_cache_get(bs, s->l2_table_cache,
+            old_l2_offset & L1E_OFFSET_MASK,
+            (void**) &old_table);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        memcpy(l2_table, old_table, s->cluster_size);
+
+        ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &old_table);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    /* write the l2 table to the file */
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_ALLOC_WRITE);
+
+    trace_qcow2_l2_allocate_write_l2(bs, l1_index);
+    qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+    ret = qcow2_cache_flush(bs, s->l2_table_cache);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* update the L1 entry */
+    trace_qcow2_l2_allocate_write_l1(bs, l1_index);
+    s->l1_table[l1_index] = l2_offset | QCOW_OFLAG_COPIED;
+    ret = write_l1_entry(bs, l1_index);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    *table = l2_table;
+    trace_qcow2_l2_allocate_done(bs, l1_index, 0);
+    return 0;
+
+fail:
+    trace_qcow2_l2_allocate_done(bs, l1_index, ret);
+    qcow2_cache_put(bs, s->l2_table_cache, (void**) table);
+    s->l1_table[l1_index] = old_l2_offset;
+    return ret;
+}
+
+/*
+ * Checks how many clusters in a given L2 table are contiguous in the image
+ * file. As soon as one of the flags in the bitmask stop_flags changes compared
+ * to the first cluster, the search is stopped and the cluster is not counted
+ * as contiguous. (This allows it, for example, to stop at the first compressed
+ * cluster which may require a different handling)
+ */
+static int count_contiguous_clusters(uint64_t nb_clusters, int cluster_size,
+        uint64_t *l2_table, uint64_t start, uint64_t stop_flags)
+{
+    int i;
+    uint64_t mask = stop_flags | L2E_OFFSET_MASK;
+    uint64_t offset = be64_to_cpu(l2_table[0]) & mask;
+
+    if (!offset)
+        return 0;
+
+    for (i = start; i < start + nb_clusters; i++) {
+        uint64_t l2_entry = be64_to_cpu(l2_table[i]) & mask;
+        if (offset + (uint64_t) i * cluster_size != l2_entry) {
+            break;
+        }
+    }
+
+	return (i - start);
+}
+
+static int count_contiguous_free_clusters(uint64_t nb_clusters, uint64_t *l2_table)
+{
+    int i;
+
+    for (i = 0; i < nb_clusters; i++) {
+        int type = qcow2_get_cluster_type(be64_to_cpu(l2_table[i]));
+
+        if (type != QCOW2_CLUSTER_UNALLOCATED) {
+            break;
+        }
+    }
+
+    return i;
+}
+
+/* The crypt function is compatible with the linux cryptoloop
+   algorithm for < 4 GB images. NOTE: out_buf == in_buf is
+   supported */
+void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+                           uint8_t *out_buf, const uint8_t *in_buf,
+                           int nb_sectors, int enc,
+                           const AES_KEY *key)
+{
+    union {
+        uint64_t ll[2];
+        uint8_t b[16];
+    } ivec;
+    int i;
+
+    for(i = 0; i < nb_sectors; i++) {
+        ivec.ll[0] = cpu_to_le64(sector_num);
+        ivec.ll[1] = 0;
+        AES_cbc_encrypt(in_buf, out_buf, 512, key,
+                        ivec.b, enc);
+        sector_num++;
+        in_buf += 512;
+        out_buf += 512;
+    }
+}
+
+static int coroutine_fn copy_sectors(BlockDriverState *bs,
+                                     uint64_t start_sect,
+                                     uint64_t cluster_offset,
+                                     int n_start, int n_end)
+{
+    BDRVQcowState *s = bs->opaque;
+    QEMUIOVector qiov;
+    struct iovec iov;
+    int n, ret;
+
+    /*
+     * If this is the last cluster and it is only partially used, we must only
+     * copy until the end of the image, or bdrv_check_request will fail for the
+     * bdrv_read/write calls below.
+     */
+    if (start_sect + n_end > bs->total_sectors) {
+        n_end = bs->total_sectors - start_sect;
+    }
+
+    n = n_end - n_start;
+    if (n <= 0) {
+        return 0;
+    }
+
+    iov.iov_len = n * BDRV_SECTOR_SIZE;
+    iov.iov_base = qemu_blockalign(bs, iov.iov_len);
+
+    qemu_iovec_init_external(&qiov, &iov, 1);
+
+    BLKDBG_EVENT(bs->file, BLKDBG_COW_READ);
+
+    /* Call .bdrv_co_readv() directly instead of using the public block-layer
+     * interface.  This avoids double I/O throttling and request tracking,
+     * which can lead to deadlock when block layer copy-on-read is enabled.
+     */
+    ret = bs->drv->bdrv_co_readv(bs, start_sect + n_start, n, &qiov);
+    if (ret < 0) {
+        goto out;
+    }
+
+    if (s->crypt_method) {
+        qcow2_encrypt_sectors(s, start_sect + n_start,
+                        iov.iov_base, iov.iov_base, n, 1,
+                        &s->aes_encrypt_key);
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_COW_WRITE);
+    ret = bdrv_co_writev(bs->file, (cluster_offset >> 9) + n_start, n, &qiov);
+    if (ret < 0) {
+        goto out;
+    }
+
+    ret = 0;
+out:
+    qemu_vfree(iov.iov_base);
+    return ret;
+}
+
+
+/*
+ * get_cluster_offset
+ *
+ * For a given offset of the disk image, find the cluster offset in
+ * qcow2 file. The offset is stored in *cluster_offset.
+ *
+ * on entry, *num is the number of contiguous sectors we'd like to
+ * access following offset.
+ *
+ * on exit, *num is the number of contiguous sectors we can read.
+ *
+ * Returns the cluster type (QCOW2_CLUSTER_*) on success, -errno in error
+ * cases.
+ */
+int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
+    int *num, uint64_t *cluster_offset)
+{
+    BDRVQcowState *s = bs->opaque;
+    unsigned int l2_index;
+    uint64_t l1_index, l2_offset, *l2_table;
+    int l1_bits, c;
+    unsigned int index_in_cluster, nb_clusters;
+    uint64_t nb_available, nb_needed;
+    int ret;
+
+    index_in_cluster = (offset >> 9) & (s->cluster_sectors - 1);
+    nb_needed = *num + index_in_cluster;
+
+    l1_bits = s->l2_bits + s->cluster_bits;
+
+    /* compute how many bytes there are between the offset and
+     * the end of the l1 entry
+     */
+
+    nb_available = (1ULL << l1_bits) - (offset & ((1ULL << l1_bits) - 1));
+
+    /* compute the number of available sectors */
+
+    nb_available = (nb_available >> 9) + index_in_cluster;
+
+    if (nb_needed > nb_available) {
+        nb_needed = nb_available;
+    }
+
+    *cluster_offset = 0;
+
+    /* seek the the l2 offset in the l1 table */
+
+    l1_index = offset >> l1_bits;
+    if (l1_index >= s->l1_size) {
+        ret = QCOW2_CLUSTER_UNALLOCATED;
+        goto out;
+    }
+
+    l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK;
+    if (!l2_offset) {
+        ret = QCOW2_CLUSTER_UNALLOCATED;
+        goto out;
+    }
+
+    /* load the l2 table in memory */
+
+    ret = l2_load(bs, l2_offset, &l2_table);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* find the cluster offset for the given disk offset */
+
+    l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+    *cluster_offset = be64_to_cpu(l2_table[l2_index]);
+    nb_clusters = size_to_clusters(s, nb_needed << 9);
+
+    ret = qcow2_get_cluster_type(*cluster_offset);
+    switch (ret) {
+    case QCOW2_CLUSTER_COMPRESSED:
+        /* Compressed clusters can only be processed one by one */
+        c = 1;
+        *cluster_offset &= L2E_COMPRESSED_OFFSET_SIZE_MASK;
+        break;
+    case QCOW2_CLUSTER_ZERO:
+        if (s->qcow_version < 3) {
+            return -EIO;
+        }
+        c = count_contiguous_clusters(nb_clusters, s->cluster_size,
+                &l2_table[l2_index], 0,
+                QCOW_OFLAG_COMPRESSED | QCOW_OFLAG_ZERO);
+        *cluster_offset = 0;
+        break;
+    case QCOW2_CLUSTER_UNALLOCATED:
+        /* how many empty clusters ? */
+        c = count_contiguous_free_clusters(nb_clusters, &l2_table[l2_index]);
+        *cluster_offset = 0;
+        break;
+    case QCOW2_CLUSTER_NORMAL:
+        /* how many allocated clusters ? */
+        c = count_contiguous_clusters(nb_clusters, s->cluster_size,
+                &l2_table[l2_index], 0,
+                QCOW_OFLAG_COMPRESSED | QCOW_OFLAG_ZERO);
+        *cluster_offset &= L2E_OFFSET_MASK;
+        break;
+    default:
+        abort();
+    }
+
+    qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+
+    nb_available = (c * s->cluster_sectors);
+
+out:
+    if (nb_available > nb_needed)
+        nb_available = nb_needed;
+
+    *num = nb_available - index_in_cluster;
+
+    return ret;
+}
+
+/*
+ * get_cluster_table
+ *
+ * for a given disk offset, load (and allocate if needed)
+ * the l2 table.
+ *
+ * the l2 table offset in the qcow2 file and the cluster index
+ * in the l2 table are given to the caller.
+ *
+ * Returns 0 on success, -errno in failure case
+ */
+static int get_cluster_table(BlockDriverState *bs, uint64_t offset,
+                             uint64_t **new_l2_table,
+                             int *new_l2_index)
+{
+    BDRVQcowState *s = bs->opaque;
+    unsigned int l2_index;
+    uint64_t l1_index, l2_offset;
+    uint64_t *l2_table = NULL;
+    int ret;
+
+    /* seek the the l2 offset in the l1 table */
+
+    l1_index = offset >> (s->l2_bits + s->cluster_bits);
+    if (l1_index >= s->l1_size) {
+        ret = qcow2_grow_l1_table(bs, l1_index + 1, false);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    assert(l1_index < s->l1_size);
+    l2_offset = s->l1_table[l1_index] & L1E_OFFSET_MASK;
+
+    /* seek the l2 table of the given l2 offset */
+
+    if (s->l1_table[l1_index] & QCOW_OFLAG_COPIED) {
+        /* load the l2 table in memory */
+        ret = l2_load(bs, l2_offset, &l2_table);
+        if (ret < 0) {
+            return ret;
+        }
+    } else {
+        /* First allocate a new L2 table (and do COW if needed) */
+        ret = l2_allocate(bs, l1_index, &l2_table);
+        if (ret < 0) {
+            return ret;
+        }
+
+        /* Then decrease the refcount of the old table */
+        if (l2_offset) {
+            qcow2_free_clusters(bs, l2_offset, s->l2_size * sizeof(uint64_t),
+                                QCOW2_DISCARD_OTHER);
+        }
+    }
+
+    /* find the cluster offset for the given disk offset */
+
+    l2_index = (offset >> s->cluster_bits) & (s->l2_size - 1);
+
+    *new_l2_table = l2_table;
+    *new_l2_index = l2_index;
+
+    return 0;
+}
+
+/*
+ * alloc_compressed_cluster_offset
+ *
+ * For a given offset of the disk image, return cluster offset in
+ * qcow2 file.
+ *
+ * If the offset is not found, allocate a new compressed cluster.
+ *
+ * Return the cluster offset if successful,
+ * Return 0, otherwise.
+ *
+ */
+
+uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
+                                               uint64_t offset,
+                                               int compressed_size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int l2_index, ret;
+    uint64_t *l2_table;
+    int64_t cluster_offset;
+    int nb_csectors;
+
+    ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        return 0;
+    }
+
+    /* Compression can't overwrite anything. Fail if the cluster was already
+     * allocated. */
+    cluster_offset = be64_to_cpu(l2_table[l2_index]);
+    if (cluster_offset & L2E_OFFSET_MASK) {
+        qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+        return 0;
+    }
+
+    cluster_offset = qcow2_alloc_bytes(bs, compressed_size);
+    if (cluster_offset < 0) {
+        qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+        return 0;
+    }
+
+    nb_csectors = ((cluster_offset + compressed_size - 1) >> 9) -
+                  (cluster_offset >> 9);
+
+    cluster_offset |= QCOW_OFLAG_COMPRESSED |
+                      ((uint64_t)nb_csectors << s->csize_shift);
+
+    /* update L2 table */
+
+    /* compressed clusters never have the copied flag */
+
+    BLKDBG_EVENT(bs->file, BLKDBG_L2_UPDATE_COMPRESSED);
+    qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+    l2_table[l2_index] = cpu_to_be64(cluster_offset);
+    ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (ret < 0) {
+        return 0;
+    }
+
+    return cluster_offset;
+}
+
+static int perform_cow(BlockDriverState *bs, QCowL2Meta *m, Qcow2COWRegion *r)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret;
+
+    if (r->nb_sectors == 0) {
+        return 0;
+    }
+
+    qemu_co_mutex_unlock(&s->lock);
+    ret = copy_sectors(bs, m->offset / BDRV_SECTOR_SIZE, m->alloc_offset,
+                       r->offset / BDRV_SECTOR_SIZE,
+                       r->offset / BDRV_SECTOR_SIZE + r->nb_sectors);
+    qemu_co_mutex_lock(&s->lock);
+
+    if (ret < 0) {
+        return ret;
+    }
+
+    /*
+     * Before we update the L2 table to actually point to the new cluster, we
+     * need to be sure that the refcounts have been increased and COW was
+     * handled.
+     */
+    qcow2_cache_depends_on_flush(s->l2_table_cache);
+
+    return 0;
+}
+
+int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i, j = 0, l2_index, ret;
+    uint64_t *old_cluster, *l2_table;
+    uint64_t cluster_offset = m->alloc_offset;
+
+    trace_qcow2_cluster_link_l2(qemu_coroutine_self(), m->nb_clusters);
+    assert(m->nb_clusters > 0);
+
+    old_cluster = g_malloc(m->nb_clusters * sizeof(uint64_t));
+
+    /* copy content of unmodified sectors */
+    ret = perform_cow(bs, m, &m->cow_start);
+    if (ret < 0) {
+        goto err;
+    }
+
+    ret = perform_cow(bs, m, &m->cow_end);
+    if (ret < 0) {
+        goto err;
+    }
+
+    /* Update L2 table. */
+    if (s->use_lazy_refcounts) {
+        qcow2_mark_dirty(bs);
+    }
+    if (qcow2_need_accurate_refcounts(s)) {
+        qcow2_cache_set_dependency(bs, s->l2_table_cache,
+                                   s->refcount_block_cache);
+    }
+
+    ret = get_cluster_table(bs, m->offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        goto err;
+    }
+    qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+
+    for (i = 0; i < m->nb_clusters; i++) {
+        /* if two concurrent writes happen to the same unallocated cluster
+	 * each write allocates separate cluster and writes data concurrently.
+	 * The first one to complete updates l2 table with pointer to its
+	 * cluster the second one has to do RMW (which is done above by
+	 * copy_sectors()), update l2 table with its cluster pointer and free
+	 * old cluster. This is what this loop does */
+        if(l2_table[l2_index + i] != 0)
+            old_cluster[j++] = l2_table[l2_index + i];
+
+        l2_table[l2_index + i] = cpu_to_be64((cluster_offset +
+                    (i << s->cluster_bits)) | QCOW_OFLAG_COPIED);
+     }
+
+
+    ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (ret < 0) {
+        goto err;
+    }
+
+    /*
+     * If this was a COW, we need to decrease the refcount of the old cluster.
+     * Also flush bs->file to get the right order for L2 and refcount update.
+     *
+     * Don't discard clusters that reach a refcount of 0 (e.g. compressed
+     * clusters), the next write will reuse them anyway.
+     */
+    if (j != 0) {
+        for (i = 0; i < j; i++) {
+            qcow2_free_any_clusters(bs, be64_to_cpu(old_cluster[i]), 1,
+                                    QCOW2_DISCARD_NEVER);
+        }
+    }
+
+    ret = 0;
+err:
+    g_free(old_cluster);
+    return ret;
+ }
+
+/*
+ * Returns the number of contiguous clusters that can be used for an allocating
+ * write, but require COW to be performed (this includes yet unallocated space,
+ * which must copy from the backing file)
+ */
+static int count_cow_clusters(BDRVQcowState *s, int nb_clusters,
+    uint64_t *l2_table, int l2_index)
+{
+    int i;
+
+    for (i = 0; i < nb_clusters; i++) {
+        uint64_t l2_entry = be64_to_cpu(l2_table[l2_index + i]);
+        int cluster_type = qcow2_get_cluster_type(l2_entry);
+
+        switch(cluster_type) {
+        case QCOW2_CLUSTER_NORMAL:
+            if (l2_entry & QCOW_OFLAG_COPIED) {
+                goto out;
+            }
+            break;
+        case QCOW2_CLUSTER_UNALLOCATED:
+        case QCOW2_CLUSTER_COMPRESSED:
+        case QCOW2_CLUSTER_ZERO:
+            break;
+        default:
+            abort();
+        }
+    }
+
+out:
+    assert(i <= nb_clusters);
+    return i;
+}
+
+/*
+ * Check if there already is an AIO write request in flight which allocates
+ * the same cluster. In this case we need to wait until the previous
+ * request has completed and updated the L2 table accordingly.
+ *
+ * Returns:
+ *   0       if there was no dependency. *cur_bytes indicates the number of
+ *           bytes from guest_offset that can be read before the next
+ *           dependency must be processed (or the request is complete)
+ *
+ *   -EAGAIN if we had to wait for another request, previously gathered
+ *           information on cluster allocation may be invalid now. The caller
+ *           must start over anyway, so consider *cur_bytes undefined.
+ */
+static int handle_dependencies(BlockDriverState *bs, uint64_t guest_offset,
+    uint64_t *cur_bytes, QCowL2Meta **m)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowL2Meta *old_alloc;
+    uint64_t bytes = *cur_bytes;
+
+    QLIST_FOREACH(old_alloc, &s->cluster_allocs, next_in_flight) {
+
+        uint64_t start = guest_offset;
+        uint64_t end = start + bytes;
+        uint64_t old_start = l2meta_cow_start(old_alloc);
+        uint64_t old_end = l2meta_cow_end(old_alloc);
+
+        if (end <= old_start || start >= old_end) {
+            /* No intersection */
+        } else {
+            if (start < old_start) {
+                /* Stop at the start of a running allocation */
+                bytes = old_start - start;
+            } else {
+                bytes = 0;
+            }
+
+            /* Stop if already an l2meta exists. After yielding, it wouldn't
+             * be valid any more, so we'd have to clean up the old L2Metas
+             * and deal with requests depending on them before starting to
+             * gather new ones. Not worth the trouble. */
+            if (bytes == 0 && *m) {
+                *cur_bytes = 0;
+                return 0;
+            }
+
+            if (bytes == 0) {
+                /* Wait for the dependency to complete. We need to recheck
+                 * the free/allocated clusters when we continue. */
+                qemu_co_mutex_unlock(&s->lock);
+                qemu_co_queue_wait(&old_alloc->dependent_requests);
+                qemu_co_mutex_lock(&s->lock);
+                return -EAGAIN;
+            }
+        }
+    }
+
+    /* Make sure that existing clusters and new allocations are only used up to
+     * the next dependency if we shortened the request above */
+    *cur_bytes = bytes;
+
+    return 0;
+}
+
+/*
+ * Checks how many already allocated clusters that don't require a copy on
+ * write there are at the given guest_offset (up to *bytes). If
+ * *host_offset is not zero, only physically contiguous clusters beginning at
+ * this host offset are counted.
+ *
+ * Note that guest_offset may not be cluster aligned. In this case, the
+ * returned *host_offset points to exact byte referenced by guest_offset and
+ * therefore isn't cluster aligned as well.
+ *
+ * Returns:
+ *   0:     if no allocated clusters are available at the given offset.
+ *          *bytes is normally unchanged. It is set to 0 if the cluster
+ *          is allocated and doesn't need COW, but doesn't have the right
+ *          physical offset.
+ *
+ *   1:     if allocated clusters that don't require a COW are available at
+ *          the requested offset. *bytes may have decreased and describes
+ *          the length of the area that can be written to.
+ *
+ *  -errno: in error cases
+ */
+static int handle_copied(BlockDriverState *bs, uint64_t guest_offset,
+    uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m)
+{
+    BDRVQcowState *s = bs->opaque;
+    int l2_index;
+    uint64_t cluster_offset;
+    uint64_t *l2_table;
+    unsigned int nb_clusters;
+    unsigned int keep_clusters;
+    int ret, pret;
+
+    trace_qcow2_handle_copied(qemu_coroutine_self(), guest_offset, *host_offset,
+                              *bytes);
+
+    assert(*host_offset == 0 ||    offset_into_cluster(s, guest_offset)
+                                == offset_into_cluster(s, *host_offset));
+
+    /*
+     * Calculate the number of clusters to look for. We stop at L2 table
+     * boundaries to keep things simple.
+     */
+    nb_clusters =
+        size_to_clusters(s, offset_into_cluster(s, guest_offset) + *bytes);
+
+    l2_index = offset_to_l2_index(s, guest_offset);
+    nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+    /* Find L2 entry for the first involved cluster */
+    ret = get_cluster_table(bs, guest_offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        return ret;
+    }
+
+    cluster_offset = be64_to_cpu(l2_table[l2_index]);
+
+    /* Check how many clusters are already allocated and don't need COW */
+    if (qcow2_get_cluster_type(cluster_offset) == QCOW2_CLUSTER_NORMAL
+        && (cluster_offset & QCOW_OFLAG_COPIED))
+    {
+        /* If a specific host_offset is required, check it */
+        bool offset_matches =
+            (cluster_offset & L2E_OFFSET_MASK) == *host_offset;
+
+        if (*host_offset != 0 && !offset_matches) {
+            *bytes = 0;
+            ret = 0;
+            goto out;
+        }
+
+        /* We keep all QCOW_OFLAG_COPIED clusters */
+        keep_clusters =
+            count_contiguous_clusters(nb_clusters, s->cluster_size,
+                                      &l2_table[l2_index], 0,
+                                      QCOW_OFLAG_COPIED | QCOW_OFLAG_ZERO);
+        assert(keep_clusters <= nb_clusters);
+
+        *bytes = MIN(*bytes,
+                 keep_clusters * s->cluster_size
+                 - offset_into_cluster(s, guest_offset));
+
+        ret = 1;
+    } else {
+        ret = 0;
+    }
+
+    /* Cleanup */
+out:
+    pret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (pret < 0) {
+        return pret;
+    }
+
+    /* Only return a host offset if we actually made progress. Otherwise we
+     * would make requirements for handle_alloc() that it can't fulfill */
+    if (ret) {
+        *host_offset = (cluster_offset & L2E_OFFSET_MASK)
+                     + offset_into_cluster(s, guest_offset);
+    }
+
+    return ret;
+}
+
+/*
+ * Allocates new clusters for the given guest_offset.
+ *
+ * At most *nb_clusters are allocated, and on return *nb_clusters is updated to
+ * contain the number of clusters that have been allocated and are contiguous
+ * in the image file.
+ *
+ * If *host_offset is non-zero, it specifies the offset in the image file at
+ * which the new clusters must start. *nb_clusters can be 0 on return in this
+ * case if the cluster at host_offset is already in use. If *host_offset is
+ * zero, the clusters can be allocated anywhere in the image file.
+ *
+ * *host_offset is updated to contain the offset into the image file at which
+ * the first allocated cluster starts.
+ *
+ * Return 0 on success and -errno in error cases. -EAGAIN means that the
+ * function has been waiting for another request and the allocation must be
+ * restarted, but the whole request should not be failed.
+ */
+static int do_alloc_cluster_offset(BlockDriverState *bs, uint64_t guest_offset,
+    uint64_t *host_offset, unsigned int *nb_clusters)
+{
+    BDRVQcowState *s = bs->opaque;
+
+    trace_qcow2_do_alloc_clusters_offset(qemu_coroutine_self(), guest_offset,
+                                         *host_offset, *nb_clusters);
+
+    /* Allocate new clusters */
+    trace_qcow2_cluster_alloc_phys(qemu_coroutine_self());
+    if (*host_offset == 0) {
+        int64_t cluster_offset =
+            qcow2_alloc_clusters(bs, *nb_clusters * s->cluster_size);
+        if (cluster_offset < 0) {
+            return cluster_offset;
+        }
+        *host_offset = cluster_offset;
+        return 0;
+    } else {
+        int ret = qcow2_alloc_clusters_at(bs, *host_offset, *nb_clusters);
+        if (ret < 0) {
+            return ret;
+        }
+        *nb_clusters = ret;
+        return 0;
+    }
+}
+
+/*
+ * Allocates new clusters for an area that either is yet unallocated or needs a
+ * copy on write. If *host_offset is non-zero, clusters are only allocated if
+ * the new allocation can match the specified host offset.
+ *
+ * Note that guest_offset may not be cluster aligned. In this case, the
+ * returned *host_offset points to exact byte referenced by guest_offset and
+ * therefore isn't cluster aligned as well.
+ *
+ * Returns:
+ *   0:     if no clusters could be allocated. *bytes is set to 0,
+ *          *host_offset is left unchanged.
+ *
+ *   1:     if new clusters were allocated. *bytes may be decreased if the
+ *          new allocation doesn't cover all of the requested area.
+ *          *host_offset is updated to contain the host offset of the first
+ *          newly allocated cluster.
+ *
+ *  -errno: in error cases
+ */
+static int handle_alloc(BlockDriverState *bs, uint64_t guest_offset,
+    uint64_t *host_offset, uint64_t *bytes, QCowL2Meta **m)
+{
+    BDRVQcowState *s = bs->opaque;
+    int l2_index;
+    uint64_t *l2_table;
+    uint64_t entry;
+    unsigned int nb_clusters;
+    int ret;
+
+    uint64_t alloc_cluster_offset;
+
+    trace_qcow2_handle_alloc(qemu_coroutine_self(), guest_offset, *host_offset,
+                             *bytes);
+    assert(*bytes > 0);
+
+    /*
+     * Calculate the number of clusters to look for. We stop at L2 table
+     * boundaries to keep things simple.
+     */
+    nb_clusters =
+        size_to_clusters(s, offset_into_cluster(s, guest_offset) + *bytes);
+
+    l2_index = offset_to_l2_index(s, guest_offset);
+    nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+    /* Find L2 entry for the first involved cluster */
+    ret = get_cluster_table(bs, guest_offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        return ret;
+    }
+
+    entry = be64_to_cpu(l2_table[l2_index]);
+
+    /* For the moment, overwrite compressed clusters one by one */
+    if (entry & QCOW_OFLAG_COMPRESSED) {
+        nb_clusters = 1;
+    } else {
+        nb_clusters = count_cow_clusters(s, nb_clusters, l2_table, l2_index);
+    }
+
+    /* This function is only called when there were no non-COW clusters, so if
+     * we can't find any unallocated or COW clusters either, something is
+     * wrong with our code. */
+    assert(nb_clusters > 0);
+
+    ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Allocate, if necessary at a given offset in the image file */
+    alloc_cluster_offset = start_of_cluster(s, *host_offset);
+    ret = do_alloc_cluster_offset(bs, guest_offset, &alloc_cluster_offset,
+                                  &nb_clusters);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Can't extend contiguous allocation */
+    if (nb_clusters == 0) {
+        *bytes = 0;
+        return 0;
+    }
+
+    /*
+     * Save info needed for meta data update.
+     *
+     * requested_sectors: Number of sectors from the start of the first
+     * newly allocated cluster to the end of the (possibly shortened
+     * before) write request.
+     *
+     * avail_sectors: Number of sectors from the start of the first
+     * newly allocated to the end of the last newly allocated cluster.
+     *
+     * nb_sectors: The number of sectors from the start of the first
+     * newly allocated cluster to the end of the area that the write
+     * request actually writes to (excluding COW at the end)
+     */
+    int requested_sectors =
+        (*bytes + offset_into_cluster(s, guest_offset))
+        >> BDRV_SECTOR_BITS;
+    int avail_sectors = nb_clusters
+                        << (s->cluster_bits - BDRV_SECTOR_BITS);
+    int alloc_n_start = offset_into_cluster(s, guest_offset)
+                        >> BDRV_SECTOR_BITS;
+    int nb_sectors = MIN(requested_sectors, avail_sectors);
+    QCowL2Meta *old_m = *m;
+
+    *m = g_malloc0(sizeof(**m));
+
+    **m = (QCowL2Meta) {
+        .next           = old_m,
+
+        .alloc_offset   = alloc_cluster_offset,
+        .offset         = start_of_cluster(s, guest_offset),
+        .nb_clusters    = nb_clusters,
+        .nb_available   = nb_sectors,
+
+        .cow_start = {
+            .offset     = 0,
+            .nb_sectors = alloc_n_start,
+        },
+        .cow_end = {
+            .offset     = nb_sectors * BDRV_SECTOR_SIZE,
+            .nb_sectors = avail_sectors - nb_sectors,
+        },
+    };
+    qemu_co_queue_init(&(*m)->dependent_requests);
+    QLIST_INSERT_HEAD(&s->cluster_allocs, *m, next_in_flight);
+
+    *host_offset = alloc_cluster_offset + offset_into_cluster(s, guest_offset);
+    *bytes = MIN(*bytes, (nb_sectors * BDRV_SECTOR_SIZE)
+                         - offset_into_cluster(s, guest_offset));
+    assert(*bytes != 0);
+
+    return 1;
+
+fail:
+    if (*m && (*m)->nb_clusters > 0) {
+        QLIST_REMOVE(*m, next_in_flight);
+    }
+    return ret;
+}
+
+/*
+ * alloc_cluster_offset
+ *
+ * For a given offset on the virtual disk, find the cluster offset in qcow2
+ * file. If the offset is not found, allocate a new cluster.
+ *
+ * If the cluster was already allocated, m->nb_clusters is set to 0 and
+ * other fields in m are meaningless.
+ *
+ * If the cluster is newly allocated, m->nb_clusters is set to the number of
+ * contiguous clusters that have been allocated. In this case, the other
+ * fields of m are valid and contain information about the first allocated
+ * cluster.
+ *
+ * If the request conflicts with another write request in flight, the coroutine
+ * is queued and will be reentered when the dependency has completed.
+ *
+ * Return 0 on success and -errno in error cases
+ */
+int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
+    int n_start, int n_end, int *num, uint64_t *host_offset, QCowL2Meta **m)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t start, remaining;
+    uint64_t cluster_offset;
+    uint64_t cur_bytes;
+    int ret;
+
+    trace_qcow2_alloc_clusters_offset(qemu_coroutine_self(), offset,
+                                      n_start, n_end);
+
+    assert(n_start * BDRV_SECTOR_SIZE == offset_into_cluster(s, offset));
+    offset = start_of_cluster(s, offset);
+
+again:
+    start = offset + (n_start << BDRV_SECTOR_BITS);
+    remaining = (n_end - n_start) << BDRV_SECTOR_BITS;
+    cluster_offset = 0;
+    *host_offset = 0;
+    cur_bytes = 0;
+    *m = NULL;
+
+    while (true) {
+
+        if (!*host_offset) {
+            *host_offset = start_of_cluster(s, cluster_offset);
+        }
+
+        assert(remaining >= cur_bytes);
+
+        start           += cur_bytes;
+        remaining       -= cur_bytes;
+        cluster_offset  += cur_bytes;
+
+        if (remaining == 0) {
+            break;
+        }
+
+        cur_bytes = remaining;
+
+        /*
+         * Now start gathering as many contiguous clusters as possible:
+         *
+         * 1. Check for overlaps with in-flight allocations
+         *
+         *      a) Overlap not in the first cluster -> shorten this request and
+         *         let the caller handle the rest in its next loop iteration.
+         *
+         *      b) Real overlaps of two requests. Yield and restart the search
+         *         for contiguous clusters (the situation could have changed
+         *         while we were sleeping)
+         *
+         *      c) TODO: Request starts in the same cluster as the in-flight
+         *         allocation ends. Shorten the COW of the in-fight allocation,
+         *         set cluster_offset to write to the same cluster and set up
+         *         the right synchronisation between the in-flight request and
+         *         the new one.
+         */
+        ret = handle_dependencies(bs, start, &cur_bytes, m);
+        if (ret == -EAGAIN) {
+            /* Currently handle_dependencies() doesn't yield if we already had
+             * an allocation. If it did, we would have to clean up the L2Meta
+             * structs before starting over. */
+            assert(*m == NULL);
+            goto again;
+        } else if (ret < 0) {
+            return ret;
+        } else if (cur_bytes == 0) {
+            break;
+        } else {
+            /* handle_dependencies() may have decreased cur_bytes (shortened
+             * the allocations below) so that the next dependency is processed
+             * correctly during the next loop iteration. */
+        }
+
+        /*
+         * 2. Count contiguous COPIED clusters.
+         */
+        ret = handle_copied(bs, start, &cluster_offset, &cur_bytes, m);
+        if (ret < 0) {
+            return ret;
+        } else if (ret) {
+            continue;
+        } else if (cur_bytes == 0) {
+            break;
+        }
+
+        /*
+         * 3. If the request still hasn't completed, allocate new clusters,
+         *    considering any cluster_offset of steps 1c or 2.
+         */
+        ret = handle_alloc(bs, start, &cluster_offset, &cur_bytes, m);
+        if (ret < 0) {
+            return ret;
+        } else if (ret) {
+            continue;
+        } else {
+            assert(cur_bytes == 0);
+            break;
+        }
+    }
+
+    *num = (n_end - n_start) - (remaining >> BDRV_SECTOR_BITS);
+    assert(*num > 0);
+    assert(*host_offset != 0);
+
+    return 0;
+}
+
+static int decompress_buffer(uint8_t *out_buf, int out_buf_size,
+                             const uint8_t *buf, int buf_size)
+{
+    z_stream strm1, *strm = &strm1;
+    int ret, out_len;
+
+    memset(strm, 0, sizeof(*strm));
+
+    strm->next_in = (uint8_t *)buf;
+    strm->avail_in = buf_size;
+    strm->next_out = out_buf;
+    strm->avail_out = out_buf_size;
+
+    ret = inflateInit2(strm, -12);
+    if (ret != Z_OK)
+        return -1;
+    ret = inflate(strm, Z_FINISH);
+    out_len = strm->next_out - out_buf;
+    if ((ret != Z_STREAM_END && ret != Z_BUF_ERROR) ||
+        out_len != out_buf_size) {
+        inflateEnd(strm);
+        return -1;
+    }
+    inflateEnd(strm);
+    return 0;
+}
+
+int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret, csize, nb_csectors, sector_offset;
+    uint64_t coffset;
+
+    coffset = cluster_offset & s->cluster_offset_mask;
+    if (s->cluster_cache_offset != coffset) {
+        nb_csectors = ((cluster_offset >> s->csize_shift) & s->csize_mask) + 1;
+        sector_offset = coffset & 511;
+        csize = nb_csectors * 512 - sector_offset;
+        BLKDBG_EVENT(bs->file, BLKDBG_READ_COMPRESSED);
+        ret = bdrv_read(bs->file, coffset >> 9, s->cluster_data, nb_csectors);
+        if (ret < 0) {
+            return ret;
+        }
+        if (decompress_buffer(s->cluster_cache, s->cluster_size,
+                              s->cluster_data + sector_offset, csize) < 0) {
+            return -EIO;
+        }
+        s->cluster_cache_offset = coffset;
+    }
+    return 0;
+}
+
+/*
+ * This discards as many clusters of nb_clusters as possible at once (i.e.
+ * all clusters in the same L2 table) and returns the number of discarded
+ * clusters.
+ */
+static int discard_single_l2(BlockDriverState *bs, uint64_t offset,
+    unsigned int nb_clusters)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t *l2_table;
+    int l2_index;
+    int ret;
+    int i;
+
+    ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Limit nb_clusters to one L2 table */
+    nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+    for (i = 0; i < nb_clusters; i++) {
+        uint64_t old_offset;
+
+        old_offset = be64_to_cpu(l2_table[l2_index + i]);
+        if ((old_offset & L2E_OFFSET_MASK) == 0) {
+            continue;
+        }
+
+        /* First remove L2 entries */
+        qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+        l2_table[l2_index + i] = cpu_to_be64(0);
+
+        /* Then decrease the refcount */
+        qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
+    }
+
+    ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return nb_clusters;
+}
+
+int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
+    int nb_sectors)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t end_offset;
+    unsigned int nb_clusters;
+    int ret;
+
+    end_offset = offset + (nb_sectors << BDRV_SECTOR_BITS);
+
+    /* Round start up and end down */
+    offset = align_offset(offset, s->cluster_size);
+    end_offset &= ~(s->cluster_size - 1);
+
+    if (offset > end_offset) {
+        return 0;
+    }
+
+    nb_clusters = size_to_clusters(s, end_offset - offset);
+
+    s->cache_discards = true;
+
+    /* Each L2 table is handled by its own loop iteration */
+    while (nb_clusters > 0) {
+        ret = discard_single_l2(bs, offset, nb_clusters);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        nb_clusters -= ret;
+        offset += (ret * s->cluster_size);
+    }
+
+    ret = 0;
+fail:
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
+    return ret;
+}
+
+/*
+ * This zeroes as many clusters of nb_clusters as possible at once (i.e.
+ * all clusters in the same L2 table) and returns the number of zeroed
+ * clusters.
+ */
+static int zero_single_l2(BlockDriverState *bs, uint64_t offset,
+    unsigned int nb_clusters)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t *l2_table;
+    int l2_index;
+    int ret;
+    int i;
+
+    ret = get_cluster_table(bs, offset, &l2_table, &l2_index);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Limit nb_clusters to one L2 table */
+    nb_clusters = MIN(nb_clusters, s->l2_size - l2_index);
+
+    for (i = 0; i < nb_clusters; i++) {
+        uint64_t old_offset;
+
+        old_offset = be64_to_cpu(l2_table[l2_index + i]);
+
+        /* Update L2 entries */
+        qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+        if (old_offset & QCOW_OFLAG_COMPRESSED) {
+            l2_table[l2_index + i] = cpu_to_be64(QCOW_OFLAG_ZERO);
+            qcow2_free_any_clusters(bs, old_offset, 1, QCOW2_DISCARD_REQUEST);
+        } else {
+            l2_table[l2_index + i] |= cpu_to_be64(QCOW_OFLAG_ZERO);
+        }
+    }
+
+    ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return nb_clusters;
+}
+
+int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors)
+{
+    BDRVQcowState *s = bs->opaque;
+    unsigned int nb_clusters;
+    int ret;
+
+    /* The zero flag is only supported by version 3 and newer */
+    if (s->qcow_version < 3) {
+        return -ENOTSUP;
+    }
+
+    /* Each L2 table is handled by its own loop iteration */
+    nb_clusters = size_to_clusters(s, nb_sectors << BDRV_SECTOR_BITS);
+
+    s->cache_discards = true;
+
+    while (nb_clusters > 0) {
+        ret = zero_single_l2(bs, offset, nb_clusters);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        nb_clusters -= ret;
+        offset += (ret * s->cluster_size);
+    }
+
+    ret = 0;
+fail:
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
+    return ret;
+}
diff --git a/contrib/qemu/block/qcow2-refcount.c b/contrib/qemu/block/qcow2-refcount.c
new file mode 100644
index 000000000..1244693f3
--- /dev/null
+++ b/contrib/qemu/block/qcow2-refcount.c
@@ -0,0 +1,1374 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "block/qcow2.h"
+
+static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size);
+static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
+                            int64_t offset, int64_t length,
+                            int addend, enum qcow2_discard_type type);
+
+
+/*********************************************************/
+/* refcount handling */
+
+int qcow2_refcount_init(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret, refcount_table_size2, i;
+
+    refcount_table_size2 = s->refcount_table_size * sizeof(uint64_t);
+    s->refcount_table = g_malloc(refcount_table_size2);
+    if (s->refcount_table_size > 0) {
+        BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_LOAD);
+        ret = bdrv_pread(bs->file, s->refcount_table_offset,
+                         s->refcount_table, refcount_table_size2);
+        if (ret != refcount_table_size2)
+            goto fail;
+        for(i = 0; i < s->refcount_table_size; i++)
+            be64_to_cpus(&s->refcount_table[i]);
+    }
+    return 0;
+ fail:
+    return -ENOMEM;
+}
+
+void qcow2_refcount_close(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    g_free(s->refcount_table);
+}
+
+
+static int load_refcount_block(BlockDriverState *bs,
+                               int64_t refcount_block_offset,
+                               void **refcount_block)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_LOAD);
+    ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset,
+        refcount_block);
+
+    return ret;
+}
+
+/*
+ * Returns the refcount of the cluster given by its index. Any non-negative
+ * return value is the refcount of the cluster, negative values are -errno
+ * and indicate an error.
+ */
+static int get_refcount(BlockDriverState *bs, int64_t cluster_index)
+{
+    BDRVQcowState *s = bs->opaque;
+    int refcount_table_index, block_index;
+    int64_t refcount_block_offset;
+    int ret;
+    uint16_t *refcount_block;
+    uint16_t refcount;
+
+    refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+    if (refcount_table_index >= s->refcount_table_size)
+        return 0;
+    refcount_block_offset = s->refcount_table[refcount_table_index];
+    if (!refcount_block_offset)
+        return 0;
+
+    ret = qcow2_cache_get(bs, s->refcount_block_cache, refcount_block_offset,
+        (void**) &refcount_block);
+    if (ret < 0) {
+        return ret;
+    }
+
+    block_index = cluster_index &
+        ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
+    refcount = be16_to_cpu(refcount_block[block_index]);
+
+    ret = qcow2_cache_put(bs, s->refcount_block_cache,
+        (void**) &refcount_block);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return refcount;
+}
+
+/*
+ * Rounds the refcount table size up to avoid growing the table for each single
+ * refcount block that is allocated.
+ */
+static unsigned int next_refcount_table_size(BDRVQcowState *s,
+    unsigned int min_size)
+{
+    unsigned int min_clusters = (min_size >> (s->cluster_bits - 3)) + 1;
+    unsigned int refcount_table_clusters =
+        MAX(1, s->refcount_table_size >> (s->cluster_bits - 3));
+
+    while (min_clusters > refcount_table_clusters) {
+        refcount_table_clusters = (refcount_table_clusters * 3 + 1) / 2;
+    }
+
+    return refcount_table_clusters << (s->cluster_bits - 3);
+}
+
+
+/* Checks if two offsets are described by the same refcount block */
+static int in_same_refcount_block(BDRVQcowState *s, uint64_t offset_a,
+    uint64_t offset_b)
+{
+    uint64_t block_a = offset_a >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
+    uint64_t block_b = offset_b >> (2 * s->cluster_bits - REFCOUNT_SHIFT);
+
+    return (block_a == block_b);
+}
+
+/*
+ * Loads a refcount block. If it doesn't exist yet, it is allocated first
+ * (including growing the refcount table if needed).
+ *
+ * Returns 0 on success or -errno in error case
+ */
+static int alloc_refcount_block(BlockDriverState *bs,
+    int64_t cluster_index, uint16_t **refcount_block)
+{
+    BDRVQcowState *s = bs->opaque;
+    unsigned int refcount_table_index;
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC);
+
+    /* Find the refcount block for the given cluster */
+    refcount_table_index = cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+
+    if (refcount_table_index < s->refcount_table_size) {
+
+        uint64_t refcount_block_offset =
+            s->refcount_table[refcount_table_index] & REFT_OFFSET_MASK;
+
+        /* If it's already there, we're done */
+        if (refcount_block_offset) {
+             return load_refcount_block(bs, refcount_block_offset,
+                 (void**) refcount_block);
+        }
+    }
+
+    /*
+     * If we came here, we need to allocate something. Something is at least
+     * a cluster for the new refcount block. It may also include a new refcount
+     * table if the old refcount table is too small.
+     *
+     * Note that allocating clusters here needs some special care:
+     *
+     * - We can't use the normal qcow2_alloc_clusters(), it would try to
+     *   increase the refcount and very likely we would end up with an endless
+     *   recursion. Instead we must place the refcount blocks in a way that
+     *   they can describe them themselves.
+     *
+     * - We need to consider that at this point we are inside update_refcounts
+     *   and doing the initial refcount increase. This means that some clusters
+     *   have already been allocated by the caller, but their refcount isn't
+     *   accurate yet. free_cluster_index tells us where this allocation ends
+     *   as long as we don't overwrite it by freeing clusters.
+     *
+     * - alloc_clusters_noref and qcow2_free_clusters may load a different
+     *   refcount block into the cache
+     */
+
+    *refcount_block = NULL;
+
+    /* We write to the refcount table, so we might depend on L2 tables */
+    ret = qcow2_cache_flush(bs, s->l2_table_cache);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Allocate the refcount block itself and mark it as used */
+    int64_t new_block = alloc_clusters_noref(bs, s->cluster_size);
+    if (new_block < 0) {
+        return new_block;
+    }
+
+#ifdef DEBUG_ALLOC2
+    fprintf(stderr, "qcow2: Allocate refcount block %d for %" PRIx64
+        " at %" PRIx64 "\n",
+        refcount_table_index, cluster_index << s->cluster_bits, new_block);
+#endif
+
+    if (in_same_refcount_block(s, new_block, cluster_index << s->cluster_bits)) {
+        /* Zero the new refcount block before updating it */
+        ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block,
+            (void**) refcount_block);
+        if (ret < 0) {
+            goto fail_block;
+        }
+
+        memset(*refcount_block, 0, s->cluster_size);
+
+        /* The block describes itself, need to update the cache */
+        int block_index = (new_block >> s->cluster_bits) &
+            ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
+        (*refcount_block)[block_index] = cpu_to_be16(1);
+    } else {
+        /* Described somewhere else. This can recurse at most twice before we
+         * arrive at a block that describes itself. */
+        ret = update_refcount(bs, new_block, s->cluster_size, 1,
+                              QCOW2_DISCARD_NEVER);
+        if (ret < 0) {
+            goto fail_block;
+        }
+
+        ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+        if (ret < 0) {
+            goto fail_block;
+        }
+
+        /* Initialize the new refcount block only after updating its refcount,
+         * update_refcount uses the refcount cache itself */
+        ret = qcow2_cache_get_empty(bs, s->refcount_block_cache, new_block,
+            (void**) refcount_block);
+        if (ret < 0) {
+            goto fail_block;
+        }
+
+        memset(*refcount_block, 0, s->cluster_size);
+    }
+
+    /* Now the new refcount block needs to be written to disk */
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE);
+    qcow2_cache_entry_mark_dirty(s->refcount_block_cache, *refcount_block);
+    ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+    if (ret < 0) {
+        goto fail_block;
+    }
+
+    /* If the refcount table is big enough, just hook the block up there */
+    if (refcount_table_index < s->refcount_table_size) {
+        uint64_t data64 = cpu_to_be64(new_block);
+        BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_HOOKUP);
+        ret = bdrv_pwrite_sync(bs->file,
+            s->refcount_table_offset + refcount_table_index * sizeof(uint64_t),
+            &data64, sizeof(data64));
+        if (ret < 0) {
+            goto fail_block;
+        }
+
+        s->refcount_table[refcount_table_index] = new_block;
+        return 0;
+    }
+
+    ret = qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
+    if (ret < 0) {
+        goto fail_block;
+    }
+
+    /*
+     * If we come here, we need to grow the refcount table. Again, a new
+     * refcount table needs some space and we can't simply allocate to avoid
+     * endless recursion.
+     *
+     * Therefore let's grab new refcount blocks at the end of the image, which
+     * will describe themselves and the new refcount table. This way we can
+     * reference them only in the new table and do the switch to the new
+     * refcount table at once without producing an inconsistent state in
+     * between.
+     */
+    BLKDBG_EVENT(bs->file, BLKDBG_REFTABLE_GROW);
+
+    /* Calculate the number of refcount blocks needed so far */
+    uint64_t refcount_block_clusters = 1 << (s->cluster_bits - REFCOUNT_SHIFT);
+    uint64_t blocks_used = (s->free_cluster_index +
+        refcount_block_clusters - 1) / refcount_block_clusters;
+
+    /* And now we need at least one block more for the new metadata */
+    uint64_t table_size = next_refcount_table_size(s, blocks_used + 1);
+    uint64_t last_table_size;
+    uint64_t blocks_clusters;
+    do {
+        uint64_t table_clusters =
+            size_to_clusters(s, table_size * sizeof(uint64_t));
+        blocks_clusters = 1 +
+            ((table_clusters + refcount_block_clusters - 1)
+            / refcount_block_clusters);
+        uint64_t meta_clusters = table_clusters + blocks_clusters;
+
+        last_table_size = table_size;
+        table_size = next_refcount_table_size(s, blocks_used +
+            ((meta_clusters + refcount_block_clusters - 1)
+            / refcount_block_clusters));
+
+    } while (last_table_size != table_size);
+
+#ifdef DEBUG_ALLOC2
+    fprintf(stderr, "qcow2: Grow refcount table %" PRId32 " => %" PRId64 "\n",
+        s->refcount_table_size, table_size);
+#endif
+
+    /* Create the new refcount table and blocks */
+    uint64_t meta_offset = (blocks_used * refcount_block_clusters) *
+        s->cluster_size;
+    uint64_t table_offset = meta_offset + blocks_clusters * s->cluster_size;
+    uint16_t *new_blocks = g_malloc0(blocks_clusters * s->cluster_size);
+    uint64_t *new_table = g_malloc0(table_size * sizeof(uint64_t));
+
+    assert(meta_offset >= (s->free_cluster_index * s->cluster_size));
+
+    /* Fill the new refcount table */
+    memcpy(new_table, s->refcount_table,
+        s->refcount_table_size * sizeof(uint64_t));
+    new_table[refcount_table_index] = new_block;
+
+    int i;
+    for (i = 0; i < blocks_clusters; i++) {
+        new_table[blocks_used + i] = meta_offset + (i * s->cluster_size);
+    }
+
+    /* Fill the refcount blocks */
+    uint64_t table_clusters = size_to_clusters(s, table_size * sizeof(uint64_t));
+    int block = 0;
+    for (i = 0; i < table_clusters + blocks_clusters; i++) {
+        new_blocks[block++] = cpu_to_be16(1);
+    }
+
+    /* Write refcount blocks to disk */
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_BLOCKS);
+    ret = bdrv_pwrite_sync(bs->file, meta_offset, new_blocks,
+        blocks_clusters * s->cluster_size);
+    g_free(new_blocks);
+    if (ret < 0) {
+        goto fail_table;
+    }
+
+    /* Write refcount table to disk */
+    for(i = 0; i < table_size; i++) {
+        cpu_to_be64s(&new_table[i]);
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_WRITE_TABLE);
+    ret = bdrv_pwrite_sync(bs->file, table_offset, new_table,
+        table_size * sizeof(uint64_t));
+    if (ret < 0) {
+        goto fail_table;
+    }
+
+    for(i = 0; i < table_size; i++) {
+        be64_to_cpus(&new_table[i]);
+    }
+
+    /* Hook up the new refcount table in the qcow2 header */
+    uint8_t data[12];
+    cpu_to_be64w((uint64_t*)data, table_offset);
+    cpu_to_be32w((uint32_t*)(data + 8), table_clusters);
+    BLKDBG_EVENT(bs->file, BLKDBG_REFBLOCK_ALLOC_SWITCH_TABLE);
+    ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, refcount_table_offset),
+        data, sizeof(data));
+    if (ret < 0) {
+        goto fail_table;
+    }
+
+    /* And switch it in memory */
+    uint64_t old_table_offset = s->refcount_table_offset;
+    uint64_t old_table_size = s->refcount_table_size;
+
+    g_free(s->refcount_table);
+    s->refcount_table = new_table;
+    s->refcount_table_size = table_size;
+    s->refcount_table_offset = table_offset;
+
+    /* Free old table. Remember, we must not change free_cluster_index */
+    uint64_t old_free_cluster_index = s->free_cluster_index;
+    qcow2_free_clusters(bs, old_table_offset, old_table_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_OTHER);
+    s->free_cluster_index = old_free_cluster_index;
+
+    ret = load_refcount_block(bs, new_block, (void**) refcount_block);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return 0;
+
+fail_table:
+    g_free(new_table);
+fail_block:
+    if (*refcount_block != NULL) {
+        qcow2_cache_put(bs, s->refcount_block_cache, (void**) refcount_block);
+    }
+    return ret;
+}
+
+void qcow2_process_discards(BlockDriverState *bs, int ret)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2DiscardRegion *d, *next;
+
+    QTAILQ_FOREACH_SAFE(d, &s->discards, next, next) {
+        QTAILQ_REMOVE(&s->discards, d, next);
+
+        /* Discard is optional, ignore the return value */
+        if (ret >= 0) {
+            bdrv_discard(bs->file,
+                         d->offset >> BDRV_SECTOR_BITS,
+                         d->bytes >> BDRV_SECTOR_BITS);
+        }
+
+        g_free(d);
+    }
+}
+
+static void update_refcount_discard(BlockDriverState *bs,
+                                    uint64_t offset, uint64_t length)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2DiscardRegion *d, *p, *next;
+
+    QTAILQ_FOREACH(d, &s->discards, next) {
+        uint64_t new_start = MIN(offset, d->offset);
+        uint64_t new_end = MAX(offset + length, d->offset + d->bytes);
+
+        if (new_end - new_start <= length + d->bytes) {
+            /* There can't be any overlap, areas ending up here have no
+             * references any more and therefore shouldn't get freed another
+             * time. */
+            assert(d->bytes + length == new_end - new_start);
+            d->offset = new_start;
+            d->bytes = new_end - new_start;
+            goto found;
+        }
+    }
+
+    d = g_malloc(sizeof(*d));
+    *d = (Qcow2DiscardRegion) {
+        .bs     = bs,
+        .offset = offset,
+        .bytes  = length,
+    };
+    QTAILQ_INSERT_TAIL(&s->discards, d, next);
+
+found:
+    /* Merge discard requests if they are adjacent now */
+    QTAILQ_FOREACH_SAFE(p, &s->discards, next, next) {
+        if (p == d
+            || p->offset > d->offset + d->bytes
+            || d->offset > p->offset + p->bytes)
+        {
+            continue;
+        }
+
+        /* Still no overlap possible */
+        assert(p->offset == d->offset + d->bytes
+            || d->offset == p->offset + p->bytes);
+
+        QTAILQ_REMOVE(&s->discards, p, next);
+        d->offset = MIN(d->offset, p->offset);
+        d->bytes += p->bytes;
+    }
+}
+
+/* XXX: cache several refcount block clusters ? */
+static int QEMU_WARN_UNUSED_RESULT update_refcount(BlockDriverState *bs,
+    int64_t offset, int64_t length, int addend, enum qcow2_discard_type type)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t start, last, cluster_offset;
+    uint16_t *refcount_block = NULL;
+    int64_t old_table_index = -1;
+    int ret;
+
+#ifdef DEBUG_ALLOC2
+    fprintf(stderr, "update_refcount: offset=%" PRId64 " size=%" PRId64 " addend=%d\n",
+           offset, length, addend);
+#endif
+    if (length < 0) {
+        return -EINVAL;
+    } else if (length == 0) {
+        return 0;
+    }
+
+    if (addend < 0) {
+        qcow2_cache_set_dependency(bs, s->refcount_block_cache,
+            s->l2_table_cache);
+    }
+
+    start = offset & ~(s->cluster_size - 1);
+    last = (offset + length - 1) & ~(s->cluster_size - 1);
+    for(cluster_offset = start; cluster_offset <= last;
+        cluster_offset += s->cluster_size)
+    {
+        int block_index, refcount;
+        int64_t cluster_index = cluster_offset >> s->cluster_bits;
+        int64_t table_index =
+            cluster_index >> (s->cluster_bits - REFCOUNT_SHIFT);
+
+        /* Load the refcount block and allocate it if needed */
+        if (table_index != old_table_index) {
+            if (refcount_block) {
+                ret = qcow2_cache_put(bs, s->refcount_block_cache,
+                    (void**) &refcount_block);
+                if (ret < 0) {
+                    goto fail;
+                }
+            }
+
+            ret = alloc_refcount_block(bs, cluster_index, &refcount_block);
+            if (ret < 0) {
+                goto fail;
+            }
+        }
+        old_table_index = table_index;
+
+        qcow2_cache_entry_mark_dirty(s->refcount_block_cache, refcount_block);
+
+        /* we can update the count and save it */
+        block_index = cluster_index &
+            ((1 << (s->cluster_bits - REFCOUNT_SHIFT)) - 1);
+
+        refcount = be16_to_cpu(refcount_block[block_index]);
+        refcount += addend;
+        if (refcount < 0 || refcount > 0xffff) {
+            ret = -EINVAL;
+            goto fail;
+        }
+        if (refcount == 0 && cluster_index < s->free_cluster_index) {
+            s->free_cluster_index = cluster_index;
+        }
+        refcount_block[block_index] = cpu_to_be16(refcount);
+
+        if (refcount == 0 && s->discard_passthrough[type]) {
+            update_refcount_discard(bs, cluster_offset, s->cluster_size);
+        }
+    }
+
+    ret = 0;
+fail:
+    if (!s->cache_discards) {
+        qcow2_process_discards(bs, ret);
+    }
+
+    /* Write last changed block to disk */
+    if (refcount_block) {
+        int wret;
+        wret = qcow2_cache_put(bs, s->refcount_block_cache,
+            (void**) &refcount_block);
+        if (wret < 0) {
+            return ret < 0 ? ret : wret;
+        }
+    }
+
+    /*
+     * Try do undo any updates if an error is returned (This may succeed in
+     * some cases like ENOSPC for allocating a new refcount block)
+     */
+    if (ret < 0) {
+        int dummy;
+        dummy = update_refcount(bs, offset, cluster_offset - offset, -addend,
+                                QCOW2_DISCARD_NEVER);
+        (void)dummy;
+    }
+
+    return ret;
+}
+
+/*
+ * Increases or decreases the refcount of a given cluster by one.
+ * addend must be 1 or -1.
+ *
+ * If the return value is non-negative, it is the new refcount of the cluster.
+ * If it is negative, it is -errno and indicates an error.
+ */
+static int update_cluster_refcount(BlockDriverState *bs,
+                                   int64_t cluster_index,
+                                   int addend,
+                                   enum qcow2_discard_type type)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret;
+
+    ret = update_refcount(bs, cluster_index << s->cluster_bits, 1, addend,
+                          type);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return get_refcount(bs, cluster_index);
+}
+
+
+
+/*********************************************************/
+/* cluster allocation functions */
+
+
+
+/* return < 0 if error */
+static int64_t alloc_clusters_noref(BlockDriverState *bs, int64_t size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i, nb_clusters, refcount;
+
+    nb_clusters = size_to_clusters(s, size);
+retry:
+    for(i = 0; i < nb_clusters; i++) {
+        int64_t next_cluster_index = s->free_cluster_index++;
+        refcount = get_refcount(bs, next_cluster_index);
+
+        if (refcount < 0) {
+            return refcount;
+        } else if (refcount != 0) {
+            goto retry;
+        }
+    }
+#ifdef DEBUG_ALLOC2
+    fprintf(stderr, "alloc_clusters: size=%" PRId64 " -> %" PRId64 "\n",
+            size,
+            (s->free_cluster_index - nb_clusters) << s->cluster_bits);
+#endif
+    return (s->free_cluster_index - nb_clusters) << s->cluster_bits;
+}
+
+int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size)
+{
+    int64_t offset;
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC);
+    offset = alloc_clusters_noref(bs, size);
+    if (offset < 0) {
+        return offset;
+    }
+
+    ret = update_refcount(bs, offset, size, 1, QCOW2_DISCARD_NEVER);
+    if (ret < 0) {
+        return ret;
+    }
+
+    return offset;
+}
+
+int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
+    int nb_clusters)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t cluster_index;
+    uint64_t old_free_cluster_index;
+    int i, refcount, ret;
+
+    /* Check how many clusters there are free */
+    cluster_index = offset >> s->cluster_bits;
+    for(i = 0; i < nb_clusters; i++) {
+        refcount = get_refcount(bs, cluster_index++);
+
+        if (refcount < 0) {
+            return refcount;
+        } else if (refcount != 0) {
+            break;
+        }
+    }
+
+    /* And then allocate them */
+    old_free_cluster_index = s->free_cluster_index;
+    s->free_cluster_index = cluster_index + i;
+
+    ret = update_refcount(bs, offset, i << s->cluster_bits, 1,
+                          QCOW2_DISCARD_NEVER);
+    if (ret < 0) {
+        return ret;
+    }
+
+    s->free_cluster_index = old_free_cluster_index;
+
+    return i;
+}
+
+/* only used to allocate compressed sectors. We try to allocate
+   contiguous sectors. size must be <= cluster_size */
+int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t offset, cluster_offset;
+    int free_in_cluster;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_ALLOC_BYTES);
+    assert(size > 0 && size <= s->cluster_size);
+    if (s->free_byte_offset == 0) {
+        offset = qcow2_alloc_clusters(bs, s->cluster_size);
+        if (offset < 0) {
+            return offset;
+        }
+        s->free_byte_offset = offset;
+    }
+ redo:
+    free_in_cluster = s->cluster_size -
+        (s->free_byte_offset & (s->cluster_size - 1));
+    if (size <= free_in_cluster) {
+        /* enough space in current cluster */
+        offset = s->free_byte_offset;
+        s->free_byte_offset += size;
+        free_in_cluster -= size;
+        if (free_in_cluster == 0)
+            s->free_byte_offset = 0;
+        if ((offset & (s->cluster_size - 1)) != 0)
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1,
+                                    QCOW2_DISCARD_NEVER);
+    } else {
+        offset = qcow2_alloc_clusters(bs, s->cluster_size);
+        if (offset < 0) {
+            return offset;
+        }
+        cluster_offset = s->free_byte_offset & ~(s->cluster_size - 1);
+        if ((cluster_offset + s->cluster_size) == offset) {
+            /* we are lucky: contiguous data */
+            offset = s->free_byte_offset;
+            update_cluster_refcount(bs, offset >> s->cluster_bits, 1,
+                                    QCOW2_DISCARD_NEVER);
+            s->free_byte_offset += size;
+        } else {
+            s->free_byte_offset = offset;
+            goto redo;
+        }
+    }
+
+    /* The cluster refcount was incremented, either by qcow2_alloc_clusters()
+     * or explicitly by update_cluster_refcount().  Refcount blocks must be
+     * flushed before the caller's L2 table updates.
+     */
+    qcow2_cache_set_dependency(bs, s->l2_table_cache, s->refcount_block_cache);
+    return offset;
+}
+
+void qcow2_free_clusters(BlockDriverState *bs,
+                          int64_t offset, int64_t size,
+                          enum qcow2_discard_type type)
+{
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_CLUSTER_FREE);
+    ret = update_refcount(bs, offset, size, -1, type);
+    if (ret < 0) {
+        fprintf(stderr, "qcow2_free_clusters failed: %s\n", strerror(-ret));
+        /* TODO Remember the clusters to free them later and avoid leaking */
+    }
+}
+
+/*
+ * Free a cluster using its L2 entry (handles clusters of all types, e.g.
+ * normal cluster, compressed cluster, etc.)
+ */
+void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
+                             int nb_clusters, enum qcow2_discard_type type)
+{
+    BDRVQcowState *s = bs->opaque;
+
+    switch (qcow2_get_cluster_type(l2_entry)) {
+    case QCOW2_CLUSTER_COMPRESSED:
+        {
+            int nb_csectors;
+            nb_csectors = ((l2_entry >> s->csize_shift) &
+                           s->csize_mask) + 1;
+            qcow2_free_clusters(bs,
+                (l2_entry & s->cluster_offset_mask) & ~511,
+                nb_csectors * 512, type);
+        }
+        break;
+    case QCOW2_CLUSTER_NORMAL:
+        qcow2_free_clusters(bs, l2_entry & L2E_OFFSET_MASK,
+                            nb_clusters << s->cluster_bits, type);
+        break;
+    case QCOW2_CLUSTER_UNALLOCATED:
+    case QCOW2_CLUSTER_ZERO:
+        break;
+    default:
+        abort();
+    }
+}
+
+
+
+/*********************************************************/
+/* snapshots and image creation */
+
+
+
+/* update the refcounts of snapshots and the copied flag */
+int qcow2_update_snapshot_refcount(BlockDriverState *bs,
+    int64_t l1_table_offset, int l1_size, int addend)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t *l1_table, *l2_table, l2_offset, offset, l1_size2, l1_allocated;
+    int64_t old_offset, old_l2_offset;
+    int i, j, l1_modified = 0, nb_csectors, refcount;
+    int ret;
+
+    l2_table = NULL;
+    l1_table = NULL;
+    l1_size2 = l1_size * sizeof(uint64_t);
+
+    s->cache_discards = true;
+
+    /* WARNING: qcow2_snapshot_goto relies on this function not using the
+     * l1_table_offset when it is the current s->l1_table_offset! Be careful
+     * when changing this! */
+    if (l1_table_offset != s->l1_table_offset) {
+        l1_table = g_malloc0(align_offset(l1_size2, 512));
+        l1_allocated = 1;
+
+        ret = bdrv_pread(bs->file, l1_table_offset, l1_table, l1_size2);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        for(i = 0;i < l1_size; i++)
+            be64_to_cpus(&l1_table[i]);
+    } else {
+        assert(l1_size == s->l1_size);
+        l1_table = s->l1_table;
+        l1_allocated = 0;
+    }
+
+    for(i = 0; i < l1_size; i++) {
+        l2_offset = l1_table[i];
+        if (l2_offset) {
+            old_l2_offset = l2_offset;
+            l2_offset &= L1E_OFFSET_MASK;
+
+            ret = qcow2_cache_get(bs, s->l2_table_cache, l2_offset,
+                (void**) &l2_table);
+            if (ret < 0) {
+                goto fail;
+            }
+
+            for(j = 0; j < s->l2_size; j++) {
+                offset = be64_to_cpu(l2_table[j]);
+                if (offset != 0) {
+                    old_offset = offset;
+                    offset &= ~QCOW_OFLAG_COPIED;
+                    if (offset & QCOW_OFLAG_COMPRESSED) {
+                        nb_csectors = ((offset >> s->csize_shift) &
+                                       s->csize_mask) + 1;
+                        if (addend != 0) {
+                            int ret;
+                            ret = update_refcount(bs,
+                                (offset & s->cluster_offset_mask) & ~511,
+                                nb_csectors * 512, addend,
+                                QCOW2_DISCARD_SNAPSHOT);
+                            if (ret < 0) {
+                                goto fail;
+                            }
+                        }
+                        /* compressed clusters are never modified */
+                        refcount = 2;
+                    } else {
+                        uint64_t cluster_index = (offset & L2E_OFFSET_MASK) >> s->cluster_bits;
+                        if (addend != 0) {
+                            refcount = update_cluster_refcount(bs, cluster_index, addend,
+                                                               QCOW2_DISCARD_SNAPSHOT);
+                        } else {
+                            refcount = get_refcount(bs, cluster_index);
+                        }
+
+                        if (refcount < 0) {
+                            ret = refcount;
+                            goto fail;
+                        }
+                    }
+
+                    if (refcount == 1) {
+                        offset |= QCOW_OFLAG_COPIED;
+                    }
+                    if (offset != old_offset) {
+                        if (addend > 0) {
+                            qcow2_cache_set_dependency(bs, s->l2_table_cache,
+                                s->refcount_block_cache);
+                        }
+                        l2_table[j] = cpu_to_be64(offset);
+                        qcow2_cache_entry_mark_dirty(s->l2_table_cache, l2_table);
+                    }
+                }
+            }
+
+            ret = qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+            if (ret < 0) {
+                goto fail;
+            }
+
+
+            if (addend != 0) {
+                refcount = update_cluster_refcount(bs, l2_offset >> s->cluster_bits, addend,
+                                                   QCOW2_DISCARD_SNAPSHOT);
+            } else {
+                refcount = get_refcount(bs, l2_offset >> s->cluster_bits);
+            }
+            if (refcount < 0) {
+                ret = refcount;
+                goto fail;
+            } else if (refcount == 1) {
+                l2_offset |= QCOW_OFLAG_COPIED;
+            }
+            if (l2_offset != old_l2_offset) {
+                l1_table[i] = l2_offset;
+                l1_modified = 1;
+            }
+        }
+    }
+
+    ret = bdrv_flush(bs);
+fail:
+    if (l2_table) {
+        qcow2_cache_put(bs, s->l2_table_cache, (void**) &l2_table);
+    }
+
+    s->cache_discards = false;
+    qcow2_process_discards(bs, ret);
+
+    /* Update L1 only if it isn't deleted anyway (addend = -1) */
+    if (ret == 0 && addend >= 0 && l1_modified) {
+        for (i = 0; i < l1_size; i++) {
+            cpu_to_be64s(&l1_table[i]);
+        }
+
+        ret = bdrv_pwrite_sync(bs->file, l1_table_offset, l1_table, l1_size2);
+
+        for (i = 0; i < l1_size; i++) {
+            be64_to_cpus(&l1_table[i]);
+        }
+    }
+    if (l1_allocated)
+        g_free(l1_table);
+    return ret;
+}
+
+
+
+
+/*********************************************************/
+/* refcount checking functions */
+
+
+
+/*
+ * Increases the refcount for a range of clusters in a given refcount table.
+ * This is used to construct a temporary refcount table out of L1 and L2 tables
+ * which can be compared the the refcount table saved in the image.
+ *
+ * Modifies the number of errors in res.
+ */
+static void inc_refcounts(BlockDriverState *bs,
+                          BdrvCheckResult *res,
+                          uint16_t *refcount_table,
+                          int refcount_table_size,
+                          int64_t offset, int64_t size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t start, last, cluster_offset;
+    int k;
+
+    if (size <= 0)
+        return;
+
+    start = offset & ~(s->cluster_size - 1);
+    last = (offset + size - 1) & ~(s->cluster_size - 1);
+    for(cluster_offset = start; cluster_offset <= last;
+        cluster_offset += s->cluster_size) {
+        k = cluster_offset >> s->cluster_bits;
+        if (k < 0) {
+            fprintf(stderr, "ERROR: invalid cluster offset=0x%" PRIx64 "\n",
+                cluster_offset);
+            res->corruptions++;
+        } else if (k >= refcount_table_size) {
+            fprintf(stderr, "Warning: cluster offset=0x%" PRIx64 " is after "
+                "the end of the image file, can't properly check refcounts.\n",
+                cluster_offset);
+            res->check_errors++;
+        } else {
+            if (++refcount_table[k] == 0) {
+                fprintf(stderr, "ERROR: overflow cluster offset=0x%" PRIx64
+                    "\n", cluster_offset);
+                res->corruptions++;
+            }
+        }
+    }
+}
+
+/* Flags for check_refcounts_l1() and check_refcounts_l2() */
+enum {
+    CHECK_OFLAG_COPIED = 0x1,   /* check QCOW_OFLAG_COPIED matches refcount */
+    CHECK_FRAG_INFO = 0x2,      /* update BlockFragInfo counters */
+};
+
+/*
+ * Increases the refcount in the given refcount table for the all clusters
+ * referenced in the L2 table. While doing so, performs some checks on L2
+ * entries.
+ *
+ * Returns the number of errors found by the checks or -errno if an internal
+ * error occurred.
+ */
+static int check_refcounts_l2(BlockDriverState *bs, BdrvCheckResult *res,
+    uint16_t *refcount_table, int refcount_table_size, int64_t l2_offset,
+    int flags)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t *l2_table, l2_entry;
+    uint64_t next_contiguous_offset = 0;
+    int i, l2_size, nb_csectors, refcount;
+
+    /* Read L2 table from disk */
+    l2_size = s->l2_size * sizeof(uint64_t);
+    l2_table = g_malloc(l2_size);
+
+    if (bdrv_pread(bs->file, l2_offset, l2_table, l2_size) != l2_size)
+        goto fail;
+
+    /* Do the actual checks */
+    for(i = 0; i < s->l2_size; i++) {
+        l2_entry = be64_to_cpu(l2_table[i]);
+
+        switch (qcow2_get_cluster_type(l2_entry)) {
+        case QCOW2_CLUSTER_COMPRESSED:
+            /* Compressed clusters don't have QCOW_OFLAG_COPIED */
+            if (l2_entry & QCOW_OFLAG_COPIED) {
+                fprintf(stderr, "ERROR: cluster %" PRId64 ": "
+                    "copied flag must never be set for compressed "
+                    "clusters\n", l2_entry >> s->cluster_bits);
+                l2_entry &= ~QCOW_OFLAG_COPIED;
+                res->corruptions++;
+            }
+
+            /* Mark cluster as used */
+            nb_csectors = ((l2_entry >> s->csize_shift) &
+                           s->csize_mask) + 1;
+            l2_entry &= s->cluster_offset_mask;
+            inc_refcounts(bs, res, refcount_table, refcount_table_size,
+                l2_entry & ~511, nb_csectors * 512);
+
+            if (flags & CHECK_FRAG_INFO) {
+                res->bfi.allocated_clusters++;
+                res->bfi.compressed_clusters++;
+
+                /* Compressed clusters are fragmented by nature.  Since they
+                 * take up sub-sector space but we only have sector granularity
+                 * I/O we need to re-read the same sectors even for adjacent
+                 * compressed clusters.
+                 */
+                res->bfi.fragmented_clusters++;
+            }
+            break;
+
+        case QCOW2_CLUSTER_ZERO:
+            if ((l2_entry & L2E_OFFSET_MASK) == 0) {
+                break;
+            }
+            /* fall through */
+
+        case QCOW2_CLUSTER_NORMAL:
+        {
+            /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
+            uint64_t offset = l2_entry & L2E_OFFSET_MASK;
+
+            if (flags & CHECK_OFLAG_COPIED) {
+                refcount = get_refcount(bs, offset >> s->cluster_bits);
+                if (refcount < 0) {
+                    fprintf(stderr, "Can't get refcount for offset %"
+                        PRIx64 ": %s\n", l2_entry, strerror(-refcount));
+                    goto fail;
+                }
+                if ((refcount == 1) != ((l2_entry & QCOW_OFLAG_COPIED) != 0)) {
+                    fprintf(stderr, "ERROR OFLAG_COPIED: offset=%"
+                        PRIx64 " refcount=%d\n", l2_entry, refcount);
+                    res->corruptions++;
+                }
+            }
+
+            if (flags & CHECK_FRAG_INFO) {
+                res->bfi.allocated_clusters++;
+                if (next_contiguous_offset &&
+                    offset != next_contiguous_offset) {
+                    res->bfi.fragmented_clusters++;
+                }
+                next_contiguous_offset = offset + s->cluster_size;
+            }
+
+            /* Mark cluster as used */
+            inc_refcounts(bs, res, refcount_table,refcount_table_size,
+                offset, s->cluster_size);
+
+            /* Correct offsets are cluster aligned */
+            if (offset & (s->cluster_size - 1)) {
+                fprintf(stderr, "ERROR offset=%" PRIx64 ": Cluster is not "
+                    "properly aligned; L2 entry corrupted.\n", offset);
+                res->corruptions++;
+            }
+            break;
+        }
+
+        case QCOW2_CLUSTER_UNALLOCATED:
+            break;
+
+        default:
+            abort();
+        }
+    }
+
+    g_free(l2_table);
+    return 0;
+
+fail:
+    fprintf(stderr, "ERROR: I/O error in check_refcounts_l2\n");
+    g_free(l2_table);
+    return -EIO;
+}
+
+/*
+ * Increases the refcount for the L1 table, its L2 tables and all referenced
+ * clusters in the given refcount table. While doing so, performs some checks
+ * on L1 and L2 entries.
+ *
+ * Returns the number of errors found by the checks or -errno if an internal
+ * error occurred.
+ */
+static int check_refcounts_l1(BlockDriverState *bs,
+                              BdrvCheckResult *res,
+                              uint16_t *refcount_table,
+                              int refcount_table_size,
+                              int64_t l1_table_offset, int l1_size,
+                              int flags)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t *l1_table, l2_offset, l1_size2;
+    int i, refcount, ret;
+
+    l1_size2 = l1_size * sizeof(uint64_t);
+
+    /* Mark L1 table as used */
+    inc_refcounts(bs, res, refcount_table, refcount_table_size,
+        l1_table_offset, l1_size2);
+
+    /* Read L1 table entries from disk */
+    if (l1_size2 == 0) {
+        l1_table = NULL;
+    } else {
+        l1_table = g_malloc(l1_size2);
+        if (bdrv_pread(bs->file, l1_table_offset,
+                       l1_table, l1_size2) != l1_size2)
+            goto fail;
+        for(i = 0;i < l1_size; i++)
+            be64_to_cpus(&l1_table[i]);
+    }
+
+    /* Do the actual checks */
+    for(i = 0; i < l1_size; i++) {
+        l2_offset = l1_table[i];
+        if (l2_offset) {
+            /* QCOW_OFLAG_COPIED must be set iff refcount == 1 */
+            if (flags & CHECK_OFLAG_COPIED) {
+                refcount = get_refcount(bs, (l2_offset & ~QCOW_OFLAG_COPIED)
+                    >> s->cluster_bits);
+                if (refcount < 0) {
+                    fprintf(stderr, "Can't get refcount for l2_offset %"
+                        PRIx64 ": %s\n", l2_offset, strerror(-refcount));
+                    goto fail;
+                }
+                if ((refcount == 1) != ((l2_offset & QCOW_OFLAG_COPIED) != 0)) {
+                    fprintf(stderr, "ERROR OFLAG_COPIED: l2_offset=%" PRIx64
+                        " refcount=%d\n", l2_offset, refcount);
+                    res->corruptions++;
+                }
+            }
+
+            /* Mark L2 table as used */
+            l2_offset &= L1E_OFFSET_MASK;
+            inc_refcounts(bs, res, refcount_table, refcount_table_size,
+                l2_offset, s->cluster_size);
+
+            /* L2 tables are cluster aligned */
+            if (l2_offset & (s->cluster_size - 1)) {
+                fprintf(stderr, "ERROR l2_offset=%" PRIx64 ": Table is not "
+                    "cluster aligned; L1 entry corrupted\n", l2_offset);
+                res->corruptions++;
+            }
+
+            /* Process and check L2 entries */
+            ret = check_refcounts_l2(bs, res, refcount_table,
+                                     refcount_table_size, l2_offset, flags);
+            if (ret < 0) {
+                goto fail;
+            }
+        }
+    }
+    g_free(l1_table);
+    return 0;
+
+fail:
+    fprintf(stderr, "ERROR: I/O error in check_refcounts_l1\n");
+    res->check_errors++;
+    g_free(l1_table);
+    return -EIO;
+}
+
+/*
+ * Checks an image for refcount consistency.
+ *
+ * Returns 0 if no errors are found, the number of errors in case the image is
+ * detected as corrupted, and -errno when an internal error occurred.
+ */
+int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
+                          BdrvCheckMode fix)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t size, i, highest_cluster;
+    int nb_clusters, refcount1, refcount2;
+    QCowSnapshot *sn;
+    uint16_t *refcount_table;
+    int ret;
+
+    size = bdrv_getlength(bs->file);
+    nb_clusters = size_to_clusters(s, size);
+    refcount_table = g_malloc0(nb_clusters * sizeof(uint16_t));
+
+    res->bfi.total_clusters =
+        size_to_clusters(s, bs->total_sectors * BDRV_SECTOR_SIZE);
+
+    /* header */
+    inc_refcounts(bs, res, refcount_table, nb_clusters,
+        0, s->cluster_size);
+
+    /* current L1 table */
+    ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
+                             s->l1_table_offset, s->l1_size,
+                             CHECK_OFLAG_COPIED | CHECK_FRAG_INFO);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* snapshots */
+    for(i = 0; i < s->nb_snapshots; i++) {
+        sn = s->snapshots + i;
+        ret = check_refcounts_l1(bs, res, refcount_table, nb_clusters,
+            sn->l1_table_offset, sn->l1_size, 0);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+    inc_refcounts(bs, res, refcount_table, nb_clusters,
+        s->snapshots_offset, s->snapshots_size);
+
+    /* refcount data */
+    inc_refcounts(bs, res, refcount_table, nb_clusters,
+        s->refcount_table_offset,
+        s->refcount_table_size * sizeof(uint64_t));
+
+    for(i = 0; i < s->refcount_table_size; i++) {
+        uint64_t offset, cluster;
+        offset = s->refcount_table[i];
+        cluster = offset >> s->cluster_bits;
+
+        /* Refcount blocks are cluster aligned */
+        if (offset & (s->cluster_size - 1)) {
+            fprintf(stderr, "ERROR refcount block %" PRId64 " is not "
+                "cluster aligned; refcount table entry corrupted\n", i);
+            res->corruptions++;
+            continue;
+        }
+
+        if (cluster >= nb_clusters) {
+            fprintf(stderr, "ERROR refcount block %" PRId64
+                    " is outside image\n", i);
+            res->corruptions++;
+            continue;
+        }
+
+        if (offset != 0) {
+            inc_refcounts(bs, res, refcount_table, nb_clusters,
+                offset, s->cluster_size);
+            if (refcount_table[cluster] != 1) {
+                fprintf(stderr, "ERROR refcount block %" PRId64
+                    " refcount=%d\n",
+                    i, refcount_table[cluster]);
+                res->corruptions++;
+            }
+        }
+    }
+
+    /* compare ref counts */
+    for (i = 0, highest_cluster = 0; i < nb_clusters; i++) {
+        refcount1 = get_refcount(bs, i);
+        if (refcount1 < 0) {
+            fprintf(stderr, "Can't get refcount for cluster %" PRId64 ": %s\n",
+                i, strerror(-refcount1));
+            res->check_errors++;
+            continue;
+        }
+
+        refcount2 = refcount_table[i];
+
+        if (refcount1 > 0 || refcount2 > 0) {
+            highest_cluster = i;
+        }
+
+        if (refcount1 != refcount2) {
+
+            /* Check if we're allowed to fix the mismatch */
+            int *num_fixed = NULL;
+            if (refcount1 > refcount2 && (fix & BDRV_FIX_LEAKS)) {
+                num_fixed = &res->leaks_fixed;
+            } else if (refcount1 < refcount2 && (fix & BDRV_FIX_ERRORS)) {
+                num_fixed = &res->corruptions_fixed;
+            }
+
+            fprintf(stderr, "%s cluster %" PRId64 " refcount=%d reference=%d\n",
+                   num_fixed != NULL     ? "Repairing" :
+                   refcount1 < refcount2 ? "ERROR" :
+                                           "Leaked",
+                   i, refcount1, refcount2);
+
+            if (num_fixed) {
+                ret = update_refcount(bs, i << s->cluster_bits, 1,
+                                      refcount2 - refcount1,
+                                      QCOW2_DISCARD_ALWAYS);
+                if (ret >= 0) {
+                    (*num_fixed)++;
+                    continue;
+                }
+            }
+
+            /* And if we couldn't, print an error */
+            if (refcount1 < refcount2) {
+                res->corruptions++;
+            } else {
+                res->leaks++;
+            }
+        }
+    }
+
+    res->image_end_offset = (highest_cluster + 1) * s->cluster_size;
+    ret = 0;
+
+fail:
+    g_free(refcount_table);
+
+    return ret;
+}
+
diff --git a/contrib/qemu/block/qcow2-snapshot.c b/contrib/qemu/block/qcow2-snapshot.c
new file mode 100644
index 000000000..0caac9055
--- /dev/null
+++ b/contrib/qemu/block/qcow2-snapshot.c
@@ -0,0 +1,660 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "block/qcow2.h"
+
+typedef struct QEMU_PACKED QCowSnapshotHeader {
+    /* header is 8 byte aligned */
+    uint64_t l1_table_offset;
+
+    uint32_t l1_size;
+    uint16_t id_str_size;
+    uint16_t name_size;
+
+    uint32_t date_sec;
+    uint32_t date_nsec;
+
+    uint64_t vm_clock_nsec;
+
+    uint32_t vm_state_size;
+    uint32_t extra_data_size; /* for extension */
+    /* extra data follows */
+    /* id_str follows */
+    /* name follows  */
+} QCowSnapshotHeader;
+
+typedef struct QEMU_PACKED QCowSnapshotExtraData {
+    uint64_t vm_state_size_large;
+    uint64_t disk_size;
+} QCowSnapshotExtraData;
+
+void qcow2_free_snapshots(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i;
+
+    for(i = 0; i < s->nb_snapshots; i++) {
+        g_free(s->snapshots[i].name);
+        g_free(s->snapshots[i].id_str);
+    }
+    g_free(s->snapshots);
+    s->snapshots = NULL;
+    s->nb_snapshots = 0;
+}
+
+int qcow2_read_snapshots(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshotHeader h;
+    QCowSnapshotExtraData extra;
+    QCowSnapshot *sn;
+    int i, id_str_size, name_size;
+    int64_t offset;
+    uint32_t extra_data_size;
+    int ret;
+
+    if (!s->nb_snapshots) {
+        s->snapshots = NULL;
+        s->snapshots_size = 0;
+        return 0;
+    }
+
+    offset = s->snapshots_offset;
+    s->snapshots = g_malloc0(s->nb_snapshots * sizeof(QCowSnapshot));
+
+    for(i = 0; i < s->nb_snapshots; i++) {
+        /* Read statically sized part of the snapshot header */
+        offset = align_offset(offset, 8);
+        ret = bdrv_pread(bs->file, offset, &h, sizeof(h));
+        if (ret < 0) {
+            goto fail;
+        }
+
+        offset += sizeof(h);
+        sn = s->snapshots + i;
+        sn->l1_table_offset = be64_to_cpu(h.l1_table_offset);
+        sn->l1_size = be32_to_cpu(h.l1_size);
+        sn->vm_state_size = be32_to_cpu(h.vm_state_size);
+        sn->date_sec = be32_to_cpu(h.date_sec);
+        sn->date_nsec = be32_to_cpu(h.date_nsec);
+        sn->vm_clock_nsec = be64_to_cpu(h.vm_clock_nsec);
+        extra_data_size = be32_to_cpu(h.extra_data_size);
+
+        id_str_size = be16_to_cpu(h.id_str_size);
+        name_size = be16_to_cpu(h.name_size);
+
+        /* Read extra data */
+        ret = bdrv_pread(bs->file, offset, &extra,
+                         MIN(sizeof(extra), extra_data_size));
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += extra_data_size;
+
+        if (extra_data_size >= 8) {
+            sn->vm_state_size = be64_to_cpu(extra.vm_state_size_large);
+        }
+
+        if (extra_data_size >= 16) {
+            sn->disk_size = be64_to_cpu(extra.disk_size);
+        } else {
+            sn->disk_size = bs->total_sectors * BDRV_SECTOR_SIZE;
+        }
+
+        /* Read snapshot ID */
+        sn->id_str = g_malloc(id_str_size + 1);
+        ret = bdrv_pread(bs->file, offset, sn->id_str, id_str_size);
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += id_str_size;
+        sn->id_str[id_str_size] = '\0';
+
+        /* Read snapshot name */
+        sn->name = g_malloc(name_size + 1);
+        ret = bdrv_pread(bs->file, offset, sn->name, name_size);
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += name_size;
+        sn->name[name_size] = '\0';
+    }
+
+    s->snapshots_size = offset - s->snapshots_offset;
+    return 0;
+
+fail:
+    qcow2_free_snapshots(bs);
+    return ret;
+}
+
+/* add at the end of the file a new list of snapshots */
+static int qcow2_write_snapshots(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot *sn;
+    QCowSnapshotHeader h;
+    QCowSnapshotExtraData extra;
+    int i, name_size, id_str_size, snapshots_size;
+    struct {
+        uint32_t nb_snapshots;
+        uint64_t snapshots_offset;
+    } QEMU_PACKED header_data;
+    int64_t offset, snapshots_offset;
+    int ret;
+
+    /* compute the size of the snapshots */
+    offset = 0;
+    for(i = 0; i < s->nb_snapshots; i++) {
+        sn = s->snapshots + i;
+        offset = align_offset(offset, 8);
+        offset += sizeof(h);
+        offset += sizeof(extra);
+        offset += strlen(sn->id_str);
+        offset += strlen(sn->name);
+    }
+    snapshots_size = offset;
+
+    /* Allocate space for the new snapshot list */
+    snapshots_offset = qcow2_alloc_clusters(bs, snapshots_size);
+    offset = snapshots_offset;
+    if (offset < 0) {
+        return offset;
+    }
+    ret = bdrv_flush(bs);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Write all snapshots to the new list */
+    for(i = 0; i < s->nb_snapshots; i++) {
+        sn = s->snapshots + i;
+        memset(&h, 0, sizeof(h));
+        h.l1_table_offset = cpu_to_be64(sn->l1_table_offset);
+        h.l1_size = cpu_to_be32(sn->l1_size);
+        /* If it doesn't fit in 32 bit, older implementations should treat it
+         * as a disk-only snapshot rather than truncate the VM state */
+        if (sn->vm_state_size <= 0xffffffff) {
+            h.vm_state_size = cpu_to_be32(sn->vm_state_size);
+        }
+        h.date_sec = cpu_to_be32(sn->date_sec);
+        h.date_nsec = cpu_to_be32(sn->date_nsec);
+        h.vm_clock_nsec = cpu_to_be64(sn->vm_clock_nsec);
+        h.extra_data_size = cpu_to_be32(sizeof(extra));
+
+        memset(&extra, 0, sizeof(extra));
+        extra.vm_state_size_large = cpu_to_be64(sn->vm_state_size);
+        extra.disk_size = cpu_to_be64(sn->disk_size);
+
+        id_str_size = strlen(sn->id_str);
+        name_size = strlen(sn->name);
+        h.id_str_size = cpu_to_be16(id_str_size);
+        h.name_size = cpu_to_be16(name_size);
+        offset = align_offset(offset, 8);
+
+        ret = bdrv_pwrite(bs->file, offset, &h, sizeof(h));
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += sizeof(h);
+
+        ret = bdrv_pwrite(bs->file, offset, &extra, sizeof(extra));
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += sizeof(extra);
+
+        ret = bdrv_pwrite(bs->file, offset, sn->id_str, id_str_size);
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += id_str_size;
+
+        ret = bdrv_pwrite(bs->file, offset, sn->name, name_size);
+        if (ret < 0) {
+            goto fail;
+        }
+        offset += name_size;
+    }
+
+    /*
+     * Update the header to point to the new snapshot table. This requires the
+     * new table and its refcounts to be stable on disk.
+     */
+    ret = bdrv_flush(bs);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    QEMU_BUILD_BUG_ON(offsetof(QCowHeader, snapshots_offset) !=
+        offsetof(QCowHeader, nb_snapshots) + sizeof(header_data.nb_snapshots));
+
+    header_data.nb_snapshots        = cpu_to_be32(s->nb_snapshots);
+    header_data.snapshots_offset    = cpu_to_be64(snapshots_offset);
+
+    ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, nb_snapshots),
+                           &header_data, sizeof(header_data));
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* free the old snapshot table */
+    qcow2_free_clusters(bs, s->snapshots_offset, s->snapshots_size,
+                        QCOW2_DISCARD_SNAPSHOT);
+    s->snapshots_offset = snapshots_offset;
+    s->snapshots_size = snapshots_size;
+    return 0;
+
+fail:
+    return ret;
+}
+
+static void find_new_snapshot_id(BlockDriverState *bs,
+                                 char *id_str, int id_str_size)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot *sn;
+    int i, id, id_max = 0;
+
+    for(i = 0; i < s->nb_snapshots; i++) {
+        sn = s->snapshots + i;
+        id = strtoul(sn->id_str, NULL, 10);
+        if (id > id_max)
+            id_max = id;
+    }
+    snprintf(id_str, id_str_size, "%d", id_max + 1);
+}
+
+static int find_snapshot_by_id(BlockDriverState *bs, const char *id_str)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i;
+
+    for(i = 0; i < s->nb_snapshots; i++) {
+        if (!strcmp(s->snapshots[i].id_str, id_str))
+            return i;
+    }
+    return -1;
+}
+
+static int find_snapshot_by_id_or_name(BlockDriverState *bs, const char *name)
+{
+    BDRVQcowState *s = bs->opaque;
+    int i, ret;
+
+    ret = find_snapshot_by_id(bs, name);
+    if (ret >= 0)
+        return ret;
+    for(i = 0; i < s->nb_snapshots; i++) {
+        if (!strcmp(s->snapshots[i].name, name))
+            return i;
+    }
+    return -1;
+}
+
+/* if no id is provided, a new one is constructed */
+int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot *new_snapshot_list = NULL;
+    QCowSnapshot *old_snapshot_list = NULL;
+    QCowSnapshot sn1, *sn = &sn1;
+    int i, ret;
+    uint64_t *l1_table = NULL;
+    int64_t l1_table_offset;
+
+    memset(sn, 0, sizeof(*sn));
+
+    /* Generate an ID if it wasn't passed */
+    if (sn_info->id_str[0] == '\0') {
+        find_new_snapshot_id(bs, sn_info->id_str, sizeof(sn_info->id_str));
+    }
+
+    /* Check that the ID is unique */
+    if (find_snapshot_by_id(bs, sn_info->id_str) >= 0) {
+        return -EEXIST;
+    }
+
+    /* Populate sn with passed data */
+    sn->id_str = g_strdup(sn_info->id_str);
+    sn->name = g_strdup(sn_info->name);
+
+    sn->disk_size = bs->total_sectors * BDRV_SECTOR_SIZE;
+    sn->vm_state_size = sn_info->vm_state_size;
+    sn->date_sec = sn_info->date_sec;
+    sn->date_nsec = sn_info->date_nsec;
+    sn->vm_clock_nsec = sn_info->vm_clock_nsec;
+
+    /* Allocate the L1 table of the snapshot and copy the current one there. */
+    l1_table_offset = qcow2_alloc_clusters(bs, s->l1_size * sizeof(uint64_t));
+    if (l1_table_offset < 0) {
+        ret = l1_table_offset;
+        goto fail;
+    }
+
+    sn->l1_table_offset = l1_table_offset;
+    sn->l1_size = s->l1_size;
+
+    l1_table = g_malloc(s->l1_size * sizeof(uint64_t));
+    for(i = 0; i < s->l1_size; i++) {
+        l1_table[i] = cpu_to_be64(s->l1_table[i]);
+    }
+
+    ret = bdrv_pwrite(bs->file, sn->l1_table_offset, l1_table,
+                      s->l1_size * sizeof(uint64_t));
+    if (ret < 0) {
+        goto fail;
+    }
+
+    g_free(l1_table);
+    l1_table = NULL;
+
+    /*
+     * Increase the refcounts of all clusters and make sure everything is
+     * stable on disk before updating the snapshot table to contain a pointer
+     * to the new L1 table.
+     */
+    ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 1);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Append the new snapshot to the snapshot list */
+    new_snapshot_list = g_malloc((s->nb_snapshots + 1) * sizeof(QCowSnapshot));
+    if (s->snapshots) {
+        memcpy(new_snapshot_list, s->snapshots,
+               s->nb_snapshots * sizeof(QCowSnapshot));
+        old_snapshot_list = s->snapshots;
+    }
+    s->snapshots = new_snapshot_list;
+    s->snapshots[s->nb_snapshots++] = *sn;
+
+    ret = qcow2_write_snapshots(bs);
+    if (ret < 0) {
+        g_free(s->snapshots);
+        s->snapshots = old_snapshot_list;
+        goto fail;
+    }
+
+    g_free(old_snapshot_list);
+
+#ifdef DEBUG_ALLOC
+    {
+      BdrvCheckResult result = {0};
+      qcow2_check_refcounts(bs, &result, 0);
+    }
+#endif
+    return 0;
+
+fail:
+    g_free(sn->id_str);
+    g_free(sn->name);
+    g_free(l1_table);
+
+    return ret;
+}
+
+/* copy the snapshot 'snapshot_name' into the current disk image */
+int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot *sn;
+    int i, snapshot_index;
+    int cur_l1_bytes, sn_l1_bytes;
+    int ret;
+    uint64_t *sn_l1_table = NULL;
+
+    /* Search the snapshot */
+    snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
+    if (snapshot_index < 0) {
+        return -ENOENT;
+    }
+    sn = &s->snapshots[snapshot_index];
+
+    if (sn->disk_size != bs->total_sectors * BDRV_SECTOR_SIZE) {
+        error_report("qcow2: Loading snapshots with different disk "
+            "size is not implemented");
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    /*
+     * Make sure that the current L1 table is big enough to contain the whole
+     * L1 table of the snapshot. If the snapshot L1 table is smaller, the
+     * current one must be padded with zeros.
+     */
+    ret = qcow2_grow_l1_table(bs, sn->l1_size, true);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    cur_l1_bytes = s->l1_size * sizeof(uint64_t);
+    sn_l1_bytes = sn->l1_size * sizeof(uint64_t);
+
+    /*
+     * Copy the snapshot L1 table to the current L1 table.
+     *
+     * Before overwriting the old current L1 table on disk, make sure to
+     * increase all refcounts for the clusters referenced by the new one.
+     * Decrease the refcount referenced by the old one only when the L1
+     * table is overwritten.
+     */
+    sn_l1_table = g_malloc0(cur_l1_bytes);
+
+    ret = bdrv_pread(bs->file, sn->l1_table_offset, sn_l1_table, sn_l1_bytes);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    ret = qcow2_update_snapshot_refcount(bs, sn->l1_table_offset,
+                                         sn->l1_size, 1);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    ret = bdrv_pwrite_sync(bs->file, s->l1_table_offset, sn_l1_table,
+                           cur_l1_bytes);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /*
+     * Decrease refcount of clusters of current L1 table.
+     *
+     * At this point, the in-memory s->l1_table points to the old L1 table,
+     * whereas on disk we already have the new one.
+     *
+     * qcow2_update_snapshot_refcount special cases the current L1 table to use
+     * the in-memory data instead of really using the offset to load a new one,
+     * which is why this works.
+     */
+    ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset,
+                                         s->l1_size, -1);
+
+    /*
+     * Now update the in-memory L1 table to be in sync with the on-disk one. We
+     * need to do this even if updating refcounts failed.
+     */
+    for(i = 0;i < s->l1_size; i++) {
+        s->l1_table[i] = be64_to_cpu(sn_l1_table[i]);
+    }
+
+    if (ret < 0) {
+        goto fail;
+    }
+
+    g_free(sn_l1_table);
+    sn_l1_table = NULL;
+
+    /*
+     * Update QCOW_OFLAG_COPIED in the active L1 table (it may have changed
+     * when we decreased the refcount of the old snapshot.
+     */
+    ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
+    if (ret < 0) {
+        goto fail;
+    }
+
+#ifdef DEBUG_ALLOC
+    {
+        BdrvCheckResult result = {0};
+        qcow2_check_refcounts(bs, &result, 0);
+    }
+#endif
+    return 0;
+
+fail:
+    g_free(sn_l1_table);
+    return ret;
+}
+
+int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot sn;
+    int snapshot_index, ret;
+
+    /* Search the snapshot */
+    snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_id);
+    if (snapshot_index < 0) {
+        return -ENOENT;
+    }
+    sn = s->snapshots[snapshot_index];
+
+    /* Remove it from the snapshot list */
+    memmove(s->snapshots + snapshot_index,
+            s->snapshots + snapshot_index + 1,
+            (s->nb_snapshots - snapshot_index - 1) * sizeof(sn));
+    s->nb_snapshots--;
+    ret = qcow2_write_snapshots(bs);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /*
+     * The snapshot is now unused, clean up. If we fail after this point, we
+     * won't recover but just leak clusters.
+     */
+    g_free(sn.id_str);
+    g_free(sn.name);
+
+    /*
+     * Now decrease the refcounts of clusters referenced by the snapshot and
+     * free the L1 table.
+     */
+    ret = qcow2_update_snapshot_refcount(bs, sn.l1_table_offset,
+                                         sn.l1_size, -1);
+    if (ret < 0) {
+        return ret;
+    }
+    qcow2_free_clusters(bs, sn.l1_table_offset, sn.l1_size * sizeof(uint64_t),
+                        QCOW2_DISCARD_SNAPSHOT);
+
+    /* must update the copied flag on the current cluster offsets */
+    ret = qcow2_update_snapshot_refcount(bs, s->l1_table_offset, s->l1_size, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+#ifdef DEBUG_ALLOC
+    {
+        BdrvCheckResult result = {0};
+        qcow2_check_refcounts(bs, &result, 0);
+    }
+#endif
+    return 0;
+}
+
+int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab)
+{
+    BDRVQcowState *s = bs->opaque;
+    QEMUSnapshotInfo *sn_tab, *sn_info;
+    QCowSnapshot *sn;
+    int i;
+
+    if (!s->nb_snapshots) {
+        *psn_tab = NULL;
+        return s->nb_snapshots;
+    }
+
+    sn_tab = g_malloc0(s->nb_snapshots * sizeof(QEMUSnapshotInfo));
+    for(i = 0; i < s->nb_snapshots; i++) {
+        sn_info = sn_tab + i;
+        sn = s->snapshots + i;
+        pstrcpy(sn_info->id_str, sizeof(sn_info->id_str),
+                sn->id_str);
+        pstrcpy(sn_info->name, sizeof(sn_info->name),
+                sn->name);
+        sn_info->vm_state_size = sn->vm_state_size;
+        sn_info->date_sec = sn->date_sec;
+        sn_info->date_nsec = sn->date_nsec;
+        sn_info->vm_clock_nsec = sn->vm_clock_nsec;
+    }
+    *psn_tab = sn_tab;
+    return s->nb_snapshots;
+}
+
+int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name)
+{
+    int i, snapshot_index;
+    BDRVQcowState *s = bs->opaque;
+    QCowSnapshot *sn;
+    uint64_t *new_l1_table;
+    int new_l1_bytes;
+    int ret;
+
+    assert(bs->read_only);
+
+    /* Search the snapshot */
+    snapshot_index = find_snapshot_by_id_or_name(bs, snapshot_name);
+    if (snapshot_index < 0) {
+        return -ENOENT;
+    }
+    sn = &s->snapshots[snapshot_index];
+
+    /* Allocate and read in the snapshot's L1 table */
+    new_l1_bytes = s->l1_size * sizeof(uint64_t);
+    new_l1_table = g_malloc0(align_offset(new_l1_bytes, 512));
+
+    ret = bdrv_pread(bs->file, sn->l1_table_offset, new_l1_table, new_l1_bytes);
+    if (ret < 0) {
+        g_free(new_l1_table);
+        return ret;
+    }
+
+    /* Switch the L1 table */
+    g_free(s->l1_table);
+
+    s->l1_size = sn->l1_size;
+    s->l1_table_offset = sn->l1_table_offset;
+    s->l1_table = new_l1_table;
+
+    for(i = 0;i < s->l1_size; i++) {
+        be64_to_cpus(&s->l1_table[i]);
+    }
+
+    return 0;
+}
diff --git a/contrib/qemu/block/qcow2.c b/contrib/qemu/block/qcow2.c
new file mode 100644
index 000000000..0eceefe2c
--- /dev/null
+++ b/contrib/qemu/block/qcow2.c
@@ -0,0 +1,1825 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+#include "qemu-common.h"
+#include "block/block_int.h"
+#include "qemu/module.h"
+#include <zlib.h>
+#include "qemu/aes.h"
+#include "block/qcow2.h"
+#include "qemu/error-report.h"
+#include "qapi/qmp/qerror.h"
+#include "qapi/qmp/qbool.h"
+#include "trace.h"
+
+/*
+  Differences with QCOW:
+
+  - Support for multiple incremental snapshots.
+  - Memory management by reference counts.
+  - Clusters which have a reference count of one have the bit
+    QCOW_OFLAG_COPIED to optimize write performance.
+  - Size of compressed clusters is stored in sectors to reduce bit usage
+    in the cluster offsets.
+  - Support for storing additional data (such as the VM state) in the
+    snapshots.
+  - If a backing store is used, the cluster size is not constrained
+    (could be backported to QCOW).
+  - L2 tables have always a size of one cluster.
+*/
+
+
+typedef struct {
+    uint32_t magic;
+    uint32_t len;
+} QCowExtension;
+
+#define  QCOW2_EXT_MAGIC_END 0
+#define  QCOW2_EXT_MAGIC_BACKING_FORMAT 0xE2792ACA
+#define  QCOW2_EXT_MAGIC_FEATURE_TABLE 0x6803f857
+
+static int qcow2_probe(const uint8_t *buf, int buf_size, const char *filename)
+{
+    const QCowHeader *cow_header = (const void *)buf;
+
+    if (buf_size >= sizeof(QCowHeader) &&
+        be32_to_cpu(cow_header->magic) == QCOW_MAGIC &&
+        be32_to_cpu(cow_header->version) >= 2)
+        return 100;
+    else
+        return 0;
+}
+
+
+/* 
+ * read qcow2 extension and fill bs
+ * start reading from start_offset
+ * finish reading upon magic of value 0 or when end_offset reached
+ * unknown magic is skipped (future extension this version knows nothing about)
+ * return 0 upon success, non-0 otherwise
+ */
+static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset,
+                                 uint64_t end_offset, void **p_feature_table)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowExtension ext;
+    uint64_t offset;
+    int ret;
+
+#ifdef DEBUG_EXT
+    printf("qcow2_read_extensions: start=%ld end=%ld\n", start_offset, end_offset);
+#endif
+    offset = start_offset;
+    while (offset < end_offset) {
+
+#ifdef DEBUG_EXT
+        /* Sanity check */
+        if (offset > s->cluster_size)
+            printf("qcow2_read_extension: suspicious offset %lu\n", offset);
+
+        printf("attempting to read extended header in offset %lu\n", offset);
+#endif
+
+        if (bdrv_pread(bs->file, offset, &ext, sizeof(ext)) != sizeof(ext)) {
+            fprintf(stderr, "qcow2_read_extension: ERROR: "
+                    "pread fail from offset %" PRIu64 "\n",
+                    offset);
+            return 1;
+        }
+        be32_to_cpus(&ext.magic);
+        be32_to_cpus(&ext.len);
+        offset += sizeof(ext);
+#ifdef DEBUG_EXT
+        printf("ext.magic = 0x%x\n", ext.magic);
+#endif
+        if (ext.len > end_offset - offset) {
+            error_report("Header extension too large");
+            return -EINVAL;
+        }
+
+        switch (ext.magic) {
+        case QCOW2_EXT_MAGIC_END:
+            return 0;
+
+        case QCOW2_EXT_MAGIC_BACKING_FORMAT:
+            if (ext.len >= sizeof(bs->backing_format)) {
+                fprintf(stderr, "ERROR: ext_backing_format: len=%u too large"
+                        " (>=%zu)\n",
+                        ext.len, sizeof(bs->backing_format));
+                return 2;
+            }
+            if (bdrv_pread(bs->file, offset , bs->backing_format,
+                           ext.len) != ext.len)
+                return 3;
+            bs->backing_format[ext.len] = '\0';
+#ifdef DEBUG_EXT
+            printf("Qcow2: Got format extension %s\n", bs->backing_format);
+#endif
+            break;
+
+        case QCOW2_EXT_MAGIC_FEATURE_TABLE:
+            if (p_feature_table != NULL) {
+                void* feature_table = g_malloc0(ext.len + 2 * sizeof(Qcow2Feature));
+                ret = bdrv_pread(bs->file, offset , feature_table, ext.len);
+                if (ret < 0) {
+                    return ret;
+                }
+
+                *p_feature_table = feature_table;
+            }
+            break;
+
+        default:
+            /* unknown magic - save it in case we need to rewrite the header */
+            {
+                Qcow2UnknownHeaderExtension *uext;
+
+                uext = g_malloc0(sizeof(*uext)  + ext.len);
+                uext->magic = ext.magic;
+                uext->len = ext.len;
+                QLIST_INSERT_HEAD(&s->unknown_header_ext, uext, next);
+
+                ret = bdrv_pread(bs->file, offset , uext->data, uext->len);
+                if (ret < 0) {
+                    return ret;
+                }
+            }
+            break;
+        }
+
+        offset += ((ext.len + 7) & ~7);
+    }
+
+    return 0;
+}
+
+static void cleanup_unknown_header_ext(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    Qcow2UnknownHeaderExtension *uext, *next;
+
+    QLIST_FOREACH_SAFE(uext, &s->unknown_header_ext, next, next) {
+        QLIST_REMOVE(uext, next);
+        g_free(uext);
+    }
+}
+
+static void GCC_FMT_ATTR(2, 3) report_unsupported(BlockDriverState *bs,
+    const char *fmt, ...)
+{
+    char msg[64];
+    va_list ap;
+
+    va_start(ap, fmt);
+    vsnprintf(msg, sizeof(msg), fmt, ap);
+    va_end(ap);
+
+    qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+        bs->device_name, "qcow2", msg);
+}
+
+static void report_unsupported_feature(BlockDriverState *bs,
+    Qcow2Feature *table, uint64_t mask)
+{
+    while (table && table->name[0] != '\0') {
+        if (table->type == QCOW2_FEAT_TYPE_INCOMPATIBLE) {
+            if (mask & (1 << table->bit)) {
+                report_unsupported(bs, "%.46s",table->name);
+                mask &= ~(1 << table->bit);
+            }
+        }
+        table++;
+    }
+
+    if (mask) {
+        report_unsupported(bs, "Unknown incompatible feature: %" PRIx64, mask);
+    }
+}
+
+/*
+ * Sets the dirty bit and flushes afterwards if necessary.
+ *
+ * The incompatible_features bit is only set if the image file header was
+ * updated successfully.  Therefore it is not required to check the return
+ * value of this function.
+ */
+int qcow2_mark_dirty(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t val;
+    int ret;
+
+    assert(s->qcow_version >= 3);
+
+    if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {
+        return 0; /* already dirty */
+    }
+
+    val = cpu_to_be64(s->incompatible_features | QCOW2_INCOMPAT_DIRTY);
+    ret = bdrv_pwrite(bs->file, offsetof(QCowHeader, incompatible_features),
+                      &val, sizeof(val));
+    if (ret < 0) {
+        return ret;
+    }
+    ret = bdrv_flush(bs->file);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Only treat image as dirty if the header was updated successfully */
+    s->incompatible_features |= QCOW2_INCOMPAT_DIRTY;
+    return 0;
+}
+
+/*
+ * Clears the dirty bit and flushes before if necessary.  Only call this
+ * function when there are no pending requests, it does not guard against
+ * concurrent requests dirtying the image.
+ */
+static int qcow2_mark_clean(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+
+    if (s->incompatible_features & QCOW2_INCOMPAT_DIRTY) {
+        int ret = bdrv_flush(bs);
+        if (ret < 0) {
+            return ret;
+        }
+
+        s->incompatible_features &= ~QCOW2_INCOMPAT_DIRTY;
+        return qcow2_update_header(bs);
+    }
+    return 0;
+}
+
+static int qcow2_check(BlockDriverState *bs, BdrvCheckResult *result,
+                       BdrvCheckMode fix)
+{
+    int ret = qcow2_check_refcounts(bs, result, fix);
+    if (ret < 0) {
+        return ret;
+    }
+
+    if (fix && result->check_errors == 0 && result->corruptions == 0) {
+        return qcow2_mark_clean(bs);
+    }
+    return ret;
+}
+
+static QemuOptsList qcow2_runtime_opts = {
+    .name = "qcow2",
+    .head = QTAILQ_HEAD_INITIALIZER(qcow2_runtime_opts.head),
+    .desc = {
+        {
+            .name = "lazy_refcounts",
+            .type = QEMU_OPT_BOOL,
+            .help = "Postpone refcount updates",
+        },
+        {
+            .name = QCOW2_OPT_DISCARD_REQUEST,
+            .type = QEMU_OPT_BOOL,
+            .help = "Pass guest discard requests to the layer below",
+        },
+        {
+            .name = QCOW2_OPT_DISCARD_SNAPSHOT,
+            .type = QEMU_OPT_BOOL,
+            .help = "Generate discard requests when snapshot related space "
+                    "is freed",
+        },
+        {
+            .name = QCOW2_OPT_DISCARD_OTHER,
+            .type = QEMU_OPT_BOOL,
+            .help = "Generate discard requests when other clusters are freed",
+        },
+        { /* end of list */ }
+    },
+};
+
+static int qcow2_open(BlockDriverState *bs, QDict *options, int flags)
+{
+    BDRVQcowState *s = bs->opaque;
+    int len, i, ret = 0;
+    QCowHeader header;
+    QemuOpts *opts;
+    Error *local_err = NULL;
+    uint64_t ext_end;
+    uint64_t l1_vm_state_index;
+
+    ret = bdrv_pread(bs->file, 0, &header, sizeof(header));
+    if (ret < 0) {
+        goto fail;
+    }
+    be32_to_cpus(&header.magic);
+    be32_to_cpus(&header.version);
+    be64_to_cpus(&header.backing_file_offset);
+    be32_to_cpus(&header.backing_file_size);
+    be64_to_cpus(&header.size);
+    be32_to_cpus(&header.cluster_bits);
+    be32_to_cpus(&header.crypt_method);
+    be64_to_cpus(&header.l1_table_offset);
+    be32_to_cpus(&header.l1_size);
+    be64_to_cpus(&header.refcount_table_offset);
+    be32_to_cpus(&header.refcount_table_clusters);
+    be64_to_cpus(&header.snapshots_offset);
+    be32_to_cpus(&header.nb_snapshots);
+
+    if (header.magic != QCOW_MAGIC) {
+        ret = -EMEDIUMTYPE;
+        goto fail;
+    }
+    if (header.version < 2 || header.version > 3) {
+        report_unsupported(bs, "QCOW version %d", header.version);
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    s->qcow_version = header.version;
+
+    /* Initialise version 3 header fields */
+    if (header.version == 2) {
+        header.incompatible_features    = 0;
+        header.compatible_features      = 0;
+        header.autoclear_features       = 0;
+        header.refcount_order           = 4;
+        header.header_length            = 72;
+    } else {
+        be64_to_cpus(&header.incompatible_features);
+        be64_to_cpus(&header.compatible_features);
+        be64_to_cpus(&header.autoclear_features);
+        be32_to_cpus(&header.refcount_order);
+        be32_to_cpus(&header.header_length);
+    }
+
+    if (header.header_length > sizeof(header)) {
+        s->unknown_header_fields_size = header.header_length - sizeof(header);
+        s->unknown_header_fields = g_malloc(s->unknown_header_fields_size);
+        ret = bdrv_pread(bs->file, sizeof(header), s->unknown_header_fields,
+                         s->unknown_header_fields_size);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    if (header.backing_file_offset) {
+        ext_end = header.backing_file_offset;
+    } else {
+        ext_end = 1 << header.cluster_bits;
+    }
+
+    /* Handle feature bits */
+    s->incompatible_features    = header.incompatible_features;
+    s->compatible_features      = header.compatible_features;
+    s->autoclear_features       = header.autoclear_features;
+
+    if (s->incompatible_features & ~QCOW2_INCOMPAT_MASK) {
+        void *feature_table = NULL;
+        qcow2_read_extensions(bs, header.header_length, ext_end,
+                              &feature_table);
+        report_unsupported_feature(bs, feature_table,
+                                   s->incompatible_features &
+                                   ~QCOW2_INCOMPAT_MASK);
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    /* Check support for various header values */
+    if (header.refcount_order != 4) {
+        report_unsupported(bs, "%d bit reference counts",
+                           1 << header.refcount_order);
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    if (header.cluster_bits < MIN_CLUSTER_BITS ||
+        header.cluster_bits > MAX_CLUSTER_BITS) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    if (header.crypt_method > QCOW_CRYPT_AES) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    s->crypt_method_header = header.crypt_method;
+    if (s->crypt_method_header) {
+        bs->encrypted = 1;
+    }
+    s->cluster_bits = header.cluster_bits;
+    s->cluster_size = 1 << s->cluster_bits;
+    s->cluster_sectors = 1 << (s->cluster_bits - 9);
+    s->l2_bits = s->cluster_bits - 3; /* L2 is always one cluster */
+    s->l2_size = 1 << s->l2_bits;
+    bs->total_sectors = header.size / 512;
+    s->csize_shift = (62 - (s->cluster_bits - 8));
+    s->csize_mask = (1 << (s->cluster_bits - 8)) - 1;
+    s->cluster_offset_mask = (1LL << s->csize_shift) - 1;
+    s->refcount_table_offset = header.refcount_table_offset;
+    s->refcount_table_size =
+        header.refcount_table_clusters << (s->cluster_bits - 3);
+
+    s->snapshots_offset = header.snapshots_offset;
+    s->nb_snapshots = header.nb_snapshots;
+
+    /* read the level 1 table */
+    s->l1_size = header.l1_size;
+
+    l1_vm_state_index = size_to_l1(s, header.size);
+    if (l1_vm_state_index > INT_MAX) {
+        ret = -EFBIG;
+        goto fail;
+    }
+    s->l1_vm_state_index = l1_vm_state_index;
+
+    /* the L1 table must contain at least enough entries to put
+       header.size bytes */
+    if (s->l1_size < s->l1_vm_state_index) {
+        ret = -EINVAL;
+        goto fail;
+    }
+    s->l1_table_offset = header.l1_table_offset;
+    if (s->l1_size > 0) {
+        s->l1_table = g_malloc0(
+            align_offset(s->l1_size * sizeof(uint64_t), 512));
+        ret = bdrv_pread(bs->file, s->l1_table_offset, s->l1_table,
+                         s->l1_size * sizeof(uint64_t));
+        if (ret < 0) {
+            goto fail;
+        }
+        for(i = 0;i < s->l1_size; i++) {
+            be64_to_cpus(&s->l1_table[i]);
+        }
+    }
+
+    /* alloc L2 table/refcount block cache */
+    s->l2_table_cache = qcow2_cache_create(bs, L2_CACHE_SIZE);
+    s->refcount_block_cache = qcow2_cache_create(bs, REFCOUNT_CACHE_SIZE);
+
+    s->cluster_cache = g_malloc(s->cluster_size);
+    /* one more sector for decompressed data alignment */
+    s->cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size
+                                  + 512);
+    s->cluster_cache_offset = -1;
+    s->flags = flags;
+
+    ret = qcow2_refcount_init(bs);
+    if (ret != 0) {
+        goto fail;
+    }
+
+    QLIST_INIT(&s->cluster_allocs);
+    QTAILQ_INIT(&s->discards);
+
+    /* read qcow2 extensions */
+    if (qcow2_read_extensions(bs, header.header_length, ext_end, NULL)) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    /* read the backing file name */
+    if (header.backing_file_offset != 0) {
+        len = header.backing_file_size;
+        if (len > 1023) {
+            len = 1023;
+        }
+        ret = bdrv_pread(bs->file, header.backing_file_offset,
+                         bs->backing_file, len);
+        if (ret < 0) {
+            goto fail;
+        }
+        bs->backing_file[len] = '\0';
+    }
+
+    ret = qcow2_read_snapshots(bs);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    /* Clear unknown autoclear feature bits */
+    if (!bs->read_only && s->autoclear_features != 0) {
+        s->autoclear_features = 0;
+        ret = qcow2_update_header(bs);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    /* Initialise locks */
+    qemu_co_mutex_init(&s->lock);
+
+    /* Repair image if dirty */
+    if (!(flags & BDRV_O_CHECK) && !bs->read_only &&
+        (s->incompatible_features & QCOW2_INCOMPAT_DIRTY)) {
+        BdrvCheckResult result = {0};
+
+        ret = qcow2_check(bs, &result, BDRV_FIX_ERRORS);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    /* Enable lazy_refcounts according to image and command line options */
+    opts = qemu_opts_create_nofail(&qcow2_runtime_opts);
+    qemu_opts_absorb_qdict(opts, options, &local_err);
+    if (error_is_set(&local_err)) {
+        qerror_report_err(local_err);
+        error_free(local_err);
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    s->use_lazy_refcounts = qemu_opt_get_bool(opts, QCOW2_OPT_LAZY_REFCOUNTS,
+        (s->compatible_features & QCOW2_COMPAT_LAZY_REFCOUNTS));
+
+    s->discard_passthrough[QCOW2_DISCARD_NEVER] = false;
+    s->discard_passthrough[QCOW2_DISCARD_ALWAYS] = true;
+    s->discard_passthrough[QCOW2_DISCARD_REQUEST] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_REQUEST,
+                          flags & BDRV_O_UNMAP);
+    s->discard_passthrough[QCOW2_DISCARD_SNAPSHOT] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_SNAPSHOT, true);
+    s->discard_passthrough[QCOW2_DISCARD_OTHER] =
+        qemu_opt_get_bool(opts, QCOW2_OPT_DISCARD_OTHER, false);
+
+    qemu_opts_del(opts);
+
+    if (s->use_lazy_refcounts && s->qcow_version < 3) {
+        qerror_report(ERROR_CLASS_GENERIC_ERROR, "Lazy refcounts require "
+            "a qcow2 image with at least qemu 1.1 compatibility level");
+        ret = -EINVAL;
+        goto fail;
+    }
+
+#ifdef DEBUG_ALLOC
+    {
+        BdrvCheckResult result = {0};
+        qcow2_check_refcounts(bs, &result, 0);
+    }
+#endif
+    return ret;
+
+ fail:
+    g_free(s->unknown_header_fields);
+    cleanup_unknown_header_ext(bs);
+    qcow2_free_snapshots(bs);
+    qcow2_refcount_close(bs);
+    g_free(s->l1_table);
+    if (s->l2_table_cache) {
+        qcow2_cache_destroy(bs, s->l2_table_cache);
+    }
+    g_free(s->cluster_cache);
+    qemu_vfree(s->cluster_data);
+    return ret;
+}
+
+static int qcow2_set_key(BlockDriverState *bs, const char *key)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint8_t keybuf[16];
+    int len, i;
+
+    memset(keybuf, 0, 16);
+    len = strlen(key);
+    if (len > 16)
+        len = 16;
+    /* XXX: we could compress the chars to 7 bits to increase
+       entropy */
+    for(i = 0;i < len;i++) {
+        keybuf[i] = key[i];
+    }
+    s->crypt_method = s->crypt_method_header;
+
+    if (AES_set_encrypt_key(keybuf, 128, &s->aes_encrypt_key) != 0)
+        return -1;
+    if (AES_set_decrypt_key(keybuf, 128, &s->aes_decrypt_key) != 0)
+        return -1;
+#if 0
+    /* test */
+    {
+        uint8_t in[16];
+        uint8_t out[16];
+        uint8_t tmp[16];
+        for(i=0;i<16;i++)
+            in[i] = i;
+        AES_encrypt(in, tmp, &s->aes_encrypt_key);
+        AES_decrypt(tmp, out, &s->aes_decrypt_key);
+        for(i = 0; i < 16; i++)
+            printf(" %02x", tmp[i]);
+        printf("\n");
+        for(i = 0; i < 16; i++)
+            printf(" %02x", out[i]);
+        printf("\n");
+    }
+#endif
+    return 0;
+}
+
+/* We have nothing to do for QCOW2 reopen, stubs just return
+ * success */
+static int qcow2_reopen_prepare(BDRVReopenState *state,
+                                BlockReopenQueue *queue, Error **errp)
+{
+    return 0;
+}
+
+static int coroutine_fn qcow2_co_is_allocated(BlockDriverState *bs,
+        int64_t sector_num, int nb_sectors, int *pnum)
+{
+    BDRVQcowState *s = bs->opaque;
+    uint64_t cluster_offset;
+    int ret;
+
+    *pnum = nb_sectors;
+    /* FIXME We can get errors here, but the bdrv_co_is_allocated interface
+     * can't pass them on today */
+    qemu_co_mutex_lock(&s->lock);
+    ret = qcow2_get_cluster_offset(bs, sector_num << 9, pnum, &cluster_offset);
+    qemu_co_mutex_unlock(&s->lock);
+    if (ret < 0) {
+        *pnum = 0;
+    }
+
+    return (cluster_offset != 0) || (ret == QCOW2_CLUSTER_ZERO);
+}
+
+/* handle reading after the end of the backing file */
+int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
+                  int64_t sector_num, int nb_sectors)
+{
+    int n1;
+    if ((sector_num + nb_sectors) <= bs->total_sectors)
+        return nb_sectors;
+    if (sector_num >= bs->total_sectors)
+        n1 = 0;
+    else
+        n1 = bs->total_sectors - sector_num;
+
+    qemu_iovec_memset(qiov, 512 * n1, 0, 512 * (nb_sectors - n1));
+
+    return n1;
+}
+
+static coroutine_fn int qcow2_co_readv(BlockDriverState *bs, int64_t sector_num,
+                          int remaining_sectors, QEMUIOVector *qiov)
+{
+    BDRVQcowState *s = bs->opaque;
+    int index_in_cluster, n1;
+    int ret;
+    int cur_nr_sectors; /* number of sectors in current iteration */
+    uint64_t cluster_offset = 0;
+    uint64_t bytes_done = 0;
+    QEMUIOVector hd_qiov;
+    uint8_t *cluster_data = NULL;
+
+    qemu_iovec_init(&hd_qiov, qiov->niov);
+
+    qemu_co_mutex_lock(&s->lock);
+
+    while (remaining_sectors != 0) {
+
+        /* prepare next request */
+        cur_nr_sectors = remaining_sectors;
+        if (s->crypt_method) {
+            cur_nr_sectors = MIN(cur_nr_sectors,
+                QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors);
+        }
+
+        ret = qcow2_get_cluster_offset(bs, sector_num << 9,
+            &cur_nr_sectors, &cluster_offset);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        index_in_cluster = sector_num & (s->cluster_sectors - 1);
+
+        qemu_iovec_reset(&hd_qiov);
+        qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
+            cur_nr_sectors * 512);
+
+        switch (ret) {
+        case QCOW2_CLUSTER_UNALLOCATED:
+
+            if (bs->backing_hd) {
+                /* read from the base image */
+                n1 = qcow2_backing_read1(bs->backing_hd, &hd_qiov,
+                    sector_num, cur_nr_sectors);
+                if (n1 > 0) {
+                    BLKDBG_EVENT(bs->file, BLKDBG_READ_BACKING_AIO);
+                    qemu_co_mutex_unlock(&s->lock);
+                    ret = bdrv_co_readv(bs->backing_hd, sector_num,
+                                        n1, &hd_qiov);
+                    qemu_co_mutex_lock(&s->lock);
+                    if (ret < 0) {
+                        goto fail;
+                    }
+                }
+            } else {
+                /* Note: in this case, no need to wait */
+                qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);
+            }
+            break;
+
+        case QCOW2_CLUSTER_ZERO:
+            qemu_iovec_memset(&hd_qiov, 0, 0, 512 * cur_nr_sectors);
+            break;
+
+        case QCOW2_CLUSTER_COMPRESSED:
+            /* add AIO support for compressed blocks ? */
+            ret = qcow2_decompress_cluster(bs, cluster_offset);
+            if (ret < 0) {
+                goto fail;
+            }
+
+            qemu_iovec_from_buf(&hd_qiov, 0,
+                s->cluster_cache + index_in_cluster * 512,
+                512 * cur_nr_sectors);
+            break;
+
+        case QCOW2_CLUSTER_NORMAL:
+            if ((cluster_offset & 511) != 0) {
+                ret = -EIO;
+                goto fail;
+            }
+
+            if (s->crypt_method) {
+                /*
+                 * For encrypted images, read everything into a temporary
+                 * contiguous buffer on which the AES functions can work.
+                 */
+                if (!cluster_data) {
+                    cluster_data =
+                        qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
+                }
+
+                assert(cur_nr_sectors <=
+                    QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors);
+                qemu_iovec_reset(&hd_qiov);
+                qemu_iovec_add(&hd_qiov, cluster_data,
+                    512 * cur_nr_sectors);
+            }
+
+            BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
+            qemu_co_mutex_unlock(&s->lock);
+            ret = bdrv_co_readv(bs->file,
+                                (cluster_offset >> 9) + index_in_cluster,
+                                cur_nr_sectors, &hd_qiov);
+            qemu_co_mutex_lock(&s->lock);
+            if (ret < 0) {
+                goto fail;
+            }
+            if (s->crypt_method) {
+                qcow2_encrypt_sectors(s, sector_num,  cluster_data,
+                    cluster_data, cur_nr_sectors, 0, &s->aes_decrypt_key);
+                qemu_iovec_from_buf(qiov, bytes_done,
+                    cluster_data, 512 * cur_nr_sectors);
+            }
+            break;
+
+        default:
+            g_assert_not_reached();
+            ret = -EIO;
+            goto fail;
+        }
+
+        remaining_sectors -= cur_nr_sectors;
+        sector_num += cur_nr_sectors;
+        bytes_done += cur_nr_sectors * 512;
+    }
+    ret = 0;
+
+fail:
+    qemu_co_mutex_unlock(&s->lock);
+
+    qemu_iovec_destroy(&hd_qiov);
+    qemu_vfree(cluster_data);
+
+    return ret;
+}
+
+static coroutine_fn int qcow2_co_writev(BlockDriverState *bs,
+                           int64_t sector_num,
+                           int remaining_sectors,
+                           QEMUIOVector *qiov)
+{
+    BDRVQcowState *s = bs->opaque;
+    int index_in_cluster;
+    int n_end;
+    int ret;
+    int cur_nr_sectors; /* number of sectors in current iteration */
+    uint64_t cluster_offset;
+    QEMUIOVector hd_qiov;
+    uint64_t bytes_done = 0;
+    uint8_t *cluster_data = NULL;
+    QCowL2Meta *l2meta = NULL;
+
+    trace_qcow2_writev_start_req(qemu_coroutine_self(), sector_num,
+                                 remaining_sectors);
+
+    qemu_iovec_init(&hd_qiov, qiov->niov);
+
+    s->cluster_cache_offset = -1; /* disable compressed cache */
+
+    qemu_co_mutex_lock(&s->lock);
+
+    while (remaining_sectors != 0) {
+
+        l2meta = NULL;
+
+        trace_qcow2_writev_start_part(qemu_coroutine_self());
+        index_in_cluster = sector_num & (s->cluster_sectors - 1);
+        n_end = index_in_cluster + remaining_sectors;
+        if (s->crypt_method &&
+            n_end > QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors) {
+            n_end = QCOW_MAX_CRYPT_CLUSTERS * s->cluster_sectors;
+        }
+
+        ret = qcow2_alloc_cluster_offset(bs, sector_num << 9,
+            index_in_cluster, n_end, &cur_nr_sectors, &cluster_offset, &l2meta);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        assert((cluster_offset & 511) == 0);
+
+        qemu_iovec_reset(&hd_qiov);
+        qemu_iovec_concat(&hd_qiov, qiov, bytes_done,
+            cur_nr_sectors * 512);
+
+        if (s->crypt_method) {
+            if (!cluster_data) {
+                cluster_data = qemu_blockalign(bs, QCOW_MAX_CRYPT_CLUSTERS *
+                                                 s->cluster_size);
+            }
+
+            assert(hd_qiov.size <=
+                   QCOW_MAX_CRYPT_CLUSTERS * s->cluster_size);
+            qemu_iovec_to_buf(&hd_qiov, 0, cluster_data, hd_qiov.size);
+
+            qcow2_encrypt_sectors(s, sector_num, cluster_data,
+                cluster_data, cur_nr_sectors, 1, &s->aes_encrypt_key);
+
+            qemu_iovec_reset(&hd_qiov);
+            qemu_iovec_add(&hd_qiov, cluster_data,
+                cur_nr_sectors * 512);
+        }
+
+        qemu_co_mutex_unlock(&s->lock);
+        BLKDBG_EVENT(bs->file, BLKDBG_WRITE_AIO);
+        trace_qcow2_writev_data(qemu_coroutine_self(),
+                                (cluster_offset >> 9) + index_in_cluster);
+        ret = bdrv_co_writev(bs->file,
+                             (cluster_offset >> 9) + index_in_cluster,
+                             cur_nr_sectors, &hd_qiov);
+        qemu_co_mutex_lock(&s->lock);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        while (l2meta != NULL) {
+            QCowL2Meta *next;
+
+            ret = qcow2_alloc_cluster_link_l2(bs, l2meta);
+            if (ret < 0) {
+                goto fail;
+            }
+
+            /* Take the request off the list of running requests */
+            if (l2meta->nb_clusters != 0) {
+                QLIST_REMOVE(l2meta, next_in_flight);
+            }
+
+            qemu_co_queue_restart_all(&l2meta->dependent_requests);
+
+            next = l2meta->next;
+            g_free(l2meta);
+            l2meta = next;
+        }
+
+        remaining_sectors -= cur_nr_sectors;
+        sector_num += cur_nr_sectors;
+        bytes_done += cur_nr_sectors * 512;
+        trace_qcow2_writev_done_part(qemu_coroutine_self(), cur_nr_sectors);
+    }
+    ret = 0;
+
+fail:
+    qemu_co_mutex_unlock(&s->lock);
+
+    while (l2meta != NULL) {
+        QCowL2Meta *next;
+
+        if (l2meta->nb_clusters != 0) {
+            QLIST_REMOVE(l2meta, next_in_flight);
+        }
+        qemu_co_queue_restart_all(&l2meta->dependent_requests);
+
+        next = l2meta->next;
+        g_free(l2meta);
+        l2meta = next;
+    }
+
+    qemu_iovec_destroy(&hd_qiov);
+    qemu_vfree(cluster_data);
+    trace_qcow2_writev_done_req(qemu_coroutine_self(), ret);
+
+    return ret;
+}
+
+static void qcow2_close(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    g_free(s->l1_table);
+
+    qcow2_cache_flush(bs, s->l2_table_cache);
+    qcow2_cache_flush(bs, s->refcount_block_cache);
+
+    qcow2_mark_clean(bs);
+
+    qcow2_cache_destroy(bs, s->l2_table_cache);
+    qcow2_cache_destroy(bs, s->refcount_block_cache);
+
+    g_free(s->unknown_header_fields);
+    cleanup_unknown_header_ext(bs);
+
+    g_free(s->cluster_cache);
+    qemu_vfree(s->cluster_data);
+    qcow2_refcount_close(bs);
+    qcow2_free_snapshots(bs);
+}
+
+static void qcow2_invalidate_cache(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    int flags = s->flags;
+    AES_KEY aes_encrypt_key;
+    AES_KEY aes_decrypt_key;
+    uint32_t crypt_method = 0;
+    QDict *options;
+
+    /*
+     * Backing files are read-only which makes all of their metadata immutable,
+     * that means we don't have to worry about reopening them here.
+     */
+
+    if (s->crypt_method) {
+        crypt_method = s->crypt_method;
+        memcpy(&aes_encrypt_key, &s->aes_encrypt_key, sizeof(aes_encrypt_key));
+        memcpy(&aes_decrypt_key, &s->aes_decrypt_key, sizeof(aes_decrypt_key));
+    }
+
+    qcow2_close(bs);
+
+    options = qdict_new();
+    qdict_put(options, QCOW2_OPT_LAZY_REFCOUNTS,
+              qbool_from_int(s->use_lazy_refcounts));
+
+    memset(s, 0, sizeof(BDRVQcowState));
+    qcow2_open(bs, options, flags);
+
+    QDECREF(options);
+
+    if (crypt_method) {
+        s->crypt_method = crypt_method;
+        memcpy(&s->aes_encrypt_key, &aes_encrypt_key, sizeof(aes_encrypt_key));
+        memcpy(&s->aes_decrypt_key, &aes_decrypt_key, sizeof(aes_decrypt_key));
+    }
+}
+
+static size_t header_ext_add(char *buf, uint32_t magic, const void *s,
+    size_t len, size_t buflen)
+{
+    QCowExtension *ext_backing_fmt = (QCowExtension*) buf;
+    size_t ext_len = sizeof(QCowExtension) + ((len + 7) & ~7);
+
+    if (buflen < ext_len) {
+        return -ENOSPC;
+    }
+
+    *ext_backing_fmt = (QCowExtension) {
+        .magic  = cpu_to_be32(magic),
+        .len    = cpu_to_be32(len),
+    };
+    memcpy(buf + sizeof(QCowExtension), s, len);
+
+    return ext_len;
+}
+
+/*
+ * Updates the qcow2 header, including the variable length parts of it, i.e.
+ * the backing file name and all extensions. qcow2 was not designed to allow
+ * such changes, so if we run out of space (we can only use the first cluster)
+ * this function may fail.
+ *
+ * Returns 0 on success, -errno in error cases.
+ */
+int qcow2_update_header(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    QCowHeader *header;
+    char *buf;
+    size_t buflen = s->cluster_size;
+    int ret;
+    uint64_t total_size;
+    uint32_t refcount_table_clusters;
+    size_t header_length;
+    Qcow2UnknownHeaderExtension *uext;
+
+    buf = qemu_blockalign(bs, buflen);
+
+    /* Header structure */
+    header = (QCowHeader*) buf;
+
+    if (buflen < sizeof(*header)) {
+        ret = -ENOSPC;
+        goto fail;
+    }
+
+    header_length = sizeof(*header) + s->unknown_header_fields_size;
+    total_size = bs->total_sectors * BDRV_SECTOR_SIZE;
+    refcount_table_clusters = s->refcount_table_size >> (s->cluster_bits - 3);
+
+    *header = (QCowHeader) {
+        /* Version 2 fields */
+        .magic                  = cpu_to_be32(QCOW_MAGIC),
+        .version                = cpu_to_be32(s->qcow_version),
+        .backing_file_offset    = 0,
+        .backing_file_size      = 0,
+        .cluster_bits           = cpu_to_be32(s->cluster_bits),
+        .size                   = cpu_to_be64(total_size),
+        .crypt_method           = cpu_to_be32(s->crypt_method_header),
+        .l1_size                = cpu_to_be32(s->l1_size),
+        .l1_table_offset        = cpu_to_be64(s->l1_table_offset),
+        .refcount_table_offset  = cpu_to_be64(s->refcount_table_offset),
+        .refcount_table_clusters = cpu_to_be32(refcount_table_clusters),
+        .nb_snapshots           = cpu_to_be32(s->nb_snapshots),
+        .snapshots_offset       = cpu_to_be64(s->snapshots_offset),
+
+        /* Version 3 fields */
+        .incompatible_features  = cpu_to_be64(s->incompatible_features),
+        .compatible_features    = cpu_to_be64(s->compatible_features),
+        .autoclear_features     = cpu_to_be64(s->autoclear_features),
+        .refcount_order         = cpu_to_be32(3 + REFCOUNT_SHIFT),
+        .header_length          = cpu_to_be32(header_length),
+    };
+
+    /* For older versions, write a shorter header */
+    switch (s->qcow_version) {
+    case 2:
+        ret = offsetof(QCowHeader, incompatible_features);
+        break;
+    case 3:
+        ret = sizeof(*header);
+        break;
+    default:
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    buf += ret;
+    buflen -= ret;
+    memset(buf, 0, buflen);
+
+    /* Preserve any unknown field in the header */
+    if (s->unknown_header_fields_size) {
+        if (buflen < s->unknown_header_fields_size) {
+            ret = -ENOSPC;
+            goto fail;
+        }
+
+        memcpy(buf, s->unknown_header_fields, s->unknown_header_fields_size);
+        buf += s->unknown_header_fields_size;
+        buflen -= s->unknown_header_fields_size;
+    }
+
+    /* Backing file format header extension */
+    if (*bs->backing_format) {
+        ret = header_ext_add(buf, QCOW2_EXT_MAGIC_BACKING_FORMAT,
+                             bs->backing_format, strlen(bs->backing_format),
+                             buflen);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        buf += ret;
+        buflen -= ret;
+    }
+
+    /* Feature table */
+    Qcow2Feature features[] = {
+        {
+            .type = QCOW2_FEAT_TYPE_INCOMPATIBLE,
+            .bit  = QCOW2_INCOMPAT_DIRTY_BITNR,
+            .name = "dirty bit",
+        },
+        {
+            .type = QCOW2_FEAT_TYPE_COMPATIBLE,
+            .bit  = QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
+            .name = "lazy refcounts",
+        },
+    };
+
+    ret = header_ext_add(buf, QCOW2_EXT_MAGIC_FEATURE_TABLE,
+                         features, sizeof(features), buflen);
+    if (ret < 0) {
+        goto fail;
+    }
+    buf += ret;
+    buflen -= ret;
+
+    /* Keep unknown header extensions */
+    QLIST_FOREACH(uext, &s->unknown_header_ext, next) {
+        ret = header_ext_add(buf, uext->magic, uext->data, uext->len, buflen);
+        if (ret < 0) {
+            goto fail;
+        }
+
+        buf += ret;
+        buflen -= ret;
+    }
+
+    /* End of header extensions */
+    ret = header_ext_add(buf, QCOW2_EXT_MAGIC_END, NULL, 0, buflen);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    buf += ret;
+    buflen -= ret;
+
+    /* Backing file name */
+    if (*bs->backing_file) {
+        size_t backing_file_len = strlen(bs->backing_file);
+
+        if (buflen < backing_file_len) {
+            ret = -ENOSPC;
+            goto fail;
+        }
+
+        /* Using strncpy is ok here, since buf is not NUL-terminated. */
+        strncpy(buf, bs->backing_file, buflen);
+
+        header->backing_file_offset = cpu_to_be64(buf - ((char*) header));
+        header->backing_file_size   = cpu_to_be32(backing_file_len);
+    }
+
+    /* Write the new header */
+    ret = bdrv_pwrite(bs->file, 0, header, s->cluster_size);
+    if (ret < 0) {
+        goto fail;
+    }
+
+    ret = 0;
+fail:
+    qemu_vfree(header);
+    return ret;
+}
+
+static int qcow2_change_backing_file(BlockDriverState *bs,
+    const char *backing_file, const char *backing_fmt)
+{
+    pstrcpy(bs->backing_file, sizeof(bs->backing_file), backing_file ?: "");
+    pstrcpy(bs->backing_format, sizeof(bs->backing_format), backing_fmt ?: "");
+
+    return qcow2_update_header(bs);
+}
+
+static int preallocate(BlockDriverState *bs)
+{
+    uint64_t nb_sectors;
+    uint64_t offset;
+    uint64_t host_offset = 0;
+    int num;
+    int ret;
+    QCowL2Meta *meta;
+
+    nb_sectors = bdrv_getlength(bs) >> 9;
+    offset = 0;
+
+    while (nb_sectors) {
+        num = MIN(nb_sectors, INT_MAX >> 9);
+        ret = qcow2_alloc_cluster_offset(bs, offset, 0, num, &num,
+                                         &host_offset, &meta);
+        if (ret < 0) {
+            return ret;
+        }
+
+        ret = qcow2_alloc_cluster_link_l2(bs, meta);
+        if (ret < 0) {
+            qcow2_free_any_clusters(bs, meta->alloc_offset, meta->nb_clusters,
+                                    QCOW2_DISCARD_NEVER);
+            return ret;
+        }
+
+        /* There are no dependent requests, but we need to remove our request
+         * from the list of in-flight requests */
+        if (meta != NULL) {
+            QLIST_REMOVE(meta, next_in_flight);
+        }
+
+        /* TODO Preallocate data if requested */
+
+        nb_sectors -= num;
+        offset += num << 9;
+    }
+
+    /*
+     * It is expected that the image file is large enough to actually contain
+     * all of the allocated clusters (otherwise we get failing reads after
+     * EOF). Extend the image to the last allocated sector.
+     */
+    if (host_offset != 0) {
+        uint8_t buf[512];
+        memset(buf, 0, 512);
+        ret = bdrv_write(bs->file, (host_offset >> 9) + num - 1, buf, 1);
+        if (ret < 0) {
+            return ret;
+        }
+    }
+
+    return 0;
+}
+
+static int qcow2_create2(const char *filename, int64_t total_size,
+                         const char *backing_file, const char *backing_format,
+                         int flags, size_t cluster_size, int prealloc,
+                         QEMUOptionParameter *options, int version)
+{
+    /* Calculate cluster_bits */
+    int cluster_bits;
+    cluster_bits = ffs(cluster_size) - 1;
+    if (cluster_bits < MIN_CLUSTER_BITS || cluster_bits > MAX_CLUSTER_BITS ||
+        (1 << cluster_bits) != cluster_size)
+    {
+        error_report(
+            "Cluster size must be a power of two between %d and %dk",
+            1 << MIN_CLUSTER_BITS, 1 << (MAX_CLUSTER_BITS - 10));
+        return -EINVAL;
+    }
+
+    /*
+     * Open the image file and write a minimal qcow2 header.
+     *
+     * We keep things simple and start with a zero-sized image. We also
+     * do without refcount blocks or a L1 table for now. We'll fix the
+     * inconsistency later.
+     *
+     * We do need a refcount table because growing the refcount table means
+     * allocating two new refcount blocks - the seconds of which would be at
+     * 2 GB for 64k clusters, and we don't want to have a 2 GB initial file
+     * size for any qcow2 image.
+     */
+    BlockDriverState* bs;
+    QCowHeader header;
+    uint8_t* refcount_table;
+    int ret;
+
+    ret = bdrv_create_file(filename, options);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* Write the header */
+    memset(&header, 0, sizeof(header));
+    header.magic = cpu_to_be32(QCOW_MAGIC);
+    header.version = cpu_to_be32(version);
+    header.cluster_bits = cpu_to_be32(cluster_bits);
+    header.size = cpu_to_be64(0);
+    header.l1_table_offset = cpu_to_be64(0);
+    header.l1_size = cpu_to_be32(0);
+    header.refcount_table_offset = cpu_to_be64(cluster_size);
+    header.refcount_table_clusters = cpu_to_be32(1);
+    header.refcount_order = cpu_to_be32(3 + REFCOUNT_SHIFT);
+    header.header_length = cpu_to_be32(sizeof(header));
+
+    if (flags & BLOCK_FLAG_ENCRYPT) {
+        header.crypt_method = cpu_to_be32(QCOW_CRYPT_AES);
+    } else {
+        header.crypt_method = cpu_to_be32(QCOW_CRYPT_NONE);
+    }
+
+    if (flags & BLOCK_FLAG_LAZY_REFCOUNTS) {
+        header.compatible_features |=
+            cpu_to_be64(QCOW2_COMPAT_LAZY_REFCOUNTS);
+    }
+
+    ret = bdrv_pwrite(bs, 0, &header, sizeof(header));
+    if (ret < 0) {
+        goto out;
+    }
+
+    /* Write an empty refcount table */
+    refcount_table = g_malloc0(cluster_size);
+    ret = bdrv_pwrite(bs, cluster_size, refcount_table, cluster_size);
+    g_free(refcount_table);
+
+    if (ret < 0) {
+        goto out;
+    }
+
+    bdrv_close(bs);
+
+    /*
+     * And now open the image and make it consistent first (i.e. increase the
+     * refcount of the cluster that is occupied by the header and the refcount
+     * table)
+     */
+    BlockDriver* drv = bdrv_find_format("qcow2");
+    assert(drv != NULL);
+    ret = bdrv_open(bs, filename, NULL,
+        BDRV_O_RDWR | BDRV_O_CACHE_WB | BDRV_O_NO_FLUSH, drv);
+    if (ret < 0) {
+        goto out;
+    }
+
+    ret = qcow2_alloc_clusters(bs, 2 * cluster_size);
+    if (ret < 0) {
+        goto out;
+
+    } else if (ret != 0) {
+        error_report("Huh, first cluster in empty image is already in use?");
+        abort();
+    }
+
+    /* Okay, now that we have a valid image, let's give it the right size */
+    ret = bdrv_truncate(bs, total_size * BDRV_SECTOR_SIZE);
+    if (ret < 0) {
+        goto out;
+    }
+
+    /* Want a backing file? There you go.*/
+    if (backing_file) {
+        ret = bdrv_change_backing_file(bs, backing_file, backing_format);
+        if (ret < 0) {
+            goto out;
+        }
+    }
+
+    /* And if we're supposed to preallocate metadata, do that now */
+    if (prealloc) {
+        BDRVQcowState *s = bs->opaque;
+        qemu_co_mutex_lock(&s->lock);
+        ret = preallocate(bs);
+        qemu_co_mutex_unlock(&s->lock);
+        if (ret < 0) {
+            goto out;
+        }
+    }
+
+    ret = 0;
+out:
+    bdrv_delete(bs);
+    return ret;
+}
+
+static int qcow2_create(const char *filename, QEMUOptionParameter *options)
+{
+    const char *backing_file = NULL;
+    const char *backing_fmt = NULL;
+    uint64_t sectors = 0;
+    int flags = 0;
+    size_t cluster_size = DEFAULT_CLUSTER_SIZE;
+    int prealloc = 0;
+    int version = 2;
+
+    /* Read out options */
+    while (options && options->name) {
+        if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+            sectors = options->value.n / 512;
+        } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
+            backing_file = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
+            backing_fmt = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_ENCRYPT)) {
+            flags |= options->value.n ? BLOCK_FLAG_ENCRYPT : 0;
+        } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
+            if (options->value.n) {
+                cluster_size = options->value.n;
+            }
+        } else if (!strcmp(options->name, BLOCK_OPT_PREALLOC)) {
+            if (!options->value.s || !strcmp(options->value.s, "off")) {
+                prealloc = 0;
+            } else if (!strcmp(options->value.s, "metadata")) {
+                prealloc = 1;
+            } else {
+                fprintf(stderr, "Invalid preallocation mode: '%s'\n",
+                    options->value.s);
+                return -EINVAL;
+            }
+        } else if (!strcmp(options->name, BLOCK_OPT_COMPAT_LEVEL)) {
+            if (!options->value.s || !strcmp(options->value.s, "0.10")) {
+                version = 2;
+            } else if (!strcmp(options->value.s, "1.1")) {
+                version = 3;
+            } else {
+                fprintf(stderr, "Invalid compatibility level: '%s'\n",
+                    options->value.s);
+                return -EINVAL;
+            }
+        } else if (!strcmp(options->name, BLOCK_OPT_LAZY_REFCOUNTS)) {
+            flags |= options->value.n ? BLOCK_FLAG_LAZY_REFCOUNTS : 0;
+        }
+        options++;
+    }
+
+    if (backing_file && prealloc) {
+        fprintf(stderr, "Backing file and preallocation cannot be used at "
+            "the same time\n");
+        return -EINVAL;
+    }
+
+    if (version < 3 && (flags & BLOCK_FLAG_LAZY_REFCOUNTS)) {
+        fprintf(stderr, "Lazy refcounts only supported with compatibility "
+                "level 1.1 and above (use compat=1.1 or greater)\n");
+        return -EINVAL;
+    }
+
+    return qcow2_create2(filename, sectors, backing_file, backing_fmt, flags,
+                         cluster_size, prealloc, options, version);
+}
+
+static int qcow2_make_empty(BlockDriverState *bs)
+{
+#if 0
+    /* XXX: not correct */
+    BDRVQcowState *s = bs->opaque;
+    uint32_t l1_length = s->l1_size * sizeof(uint64_t);
+    int ret;
+
+    memset(s->l1_table, 0, l1_length);
+    if (bdrv_pwrite(bs->file, s->l1_table_offset, s->l1_table, l1_length) < 0)
+        return -1;
+    ret = bdrv_truncate(bs->file, s->l1_table_offset + l1_length);
+    if (ret < 0)
+        return ret;
+
+    l2_cache_reset(bs);
+#endif
+    return 0;
+}
+
+static coroutine_fn int qcow2_co_write_zeroes(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors)
+{
+    int ret;
+    BDRVQcowState *s = bs->opaque;
+
+    /* Emulate misaligned zero writes */
+    if (sector_num % s->cluster_sectors || nb_sectors % s->cluster_sectors) {
+        return -ENOTSUP;
+    }
+
+    /* Whatever is left can use real zero clusters */
+    qemu_co_mutex_lock(&s->lock);
+    ret = qcow2_zero_clusters(bs, sector_num << BDRV_SECTOR_BITS,
+        nb_sectors);
+    qemu_co_mutex_unlock(&s->lock);
+
+    return ret;
+}
+
+static coroutine_fn int qcow2_co_discard(BlockDriverState *bs,
+    int64_t sector_num, int nb_sectors)
+{
+    int ret;
+    BDRVQcowState *s = bs->opaque;
+
+    qemu_co_mutex_lock(&s->lock);
+    ret = qcow2_discard_clusters(bs, sector_num << BDRV_SECTOR_BITS,
+        nb_sectors);
+    qemu_co_mutex_unlock(&s->lock);
+    return ret;
+}
+
+static int qcow2_truncate(BlockDriverState *bs, int64_t offset)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t new_l1_size;
+    int ret;
+
+    if (offset & 511) {
+        error_report("The new size must be a multiple of 512");
+        return -EINVAL;
+    }
+
+    /* cannot proceed if image has snapshots */
+    if (s->nb_snapshots) {
+        error_report("Can't resize an image which has snapshots");
+        return -ENOTSUP;
+    }
+
+    /* shrinking is currently not supported */
+    if (offset < bs->total_sectors * 512) {
+        error_report("qcow2 doesn't support shrinking images yet");
+        return -ENOTSUP;
+    }
+
+    new_l1_size = size_to_l1(s, offset);
+    ret = qcow2_grow_l1_table(bs, new_l1_size, true);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* write updated header.size */
+    offset = cpu_to_be64(offset);
+    ret = bdrv_pwrite_sync(bs->file, offsetof(QCowHeader, size),
+                           &offset, sizeof(uint64_t));
+    if (ret < 0) {
+        return ret;
+    }
+
+    s->l1_vm_state_index = new_l1_size;
+    return 0;
+}
+
+/* XXX: put compressed sectors first, then all the cluster aligned
+   tables to avoid losing bytes in alignment */
+static int qcow2_write_compressed(BlockDriverState *bs, int64_t sector_num,
+                                  const uint8_t *buf, int nb_sectors)
+{
+    BDRVQcowState *s = bs->opaque;
+    z_stream strm;
+    int ret, out_len;
+    uint8_t *out_buf;
+    uint64_t cluster_offset;
+
+    if (nb_sectors == 0) {
+        /* align end of file to a sector boundary to ease reading with
+           sector based I/Os */
+        cluster_offset = bdrv_getlength(bs->file);
+        cluster_offset = (cluster_offset + 511) & ~511;
+        bdrv_truncate(bs->file, cluster_offset);
+        return 0;
+    }
+
+    if (nb_sectors != s->cluster_sectors) {
+        ret = -EINVAL;
+
+        /* Zero-pad last write if image size is not cluster aligned */
+        if (sector_num + nb_sectors == bs->total_sectors &&
+            nb_sectors < s->cluster_sectors) {
+            uint8_t *pad_buf = qemu_blockalign(bs, s->cluster_size);
+            memset(pad_buf, 0, s->cluster_size);
+            memcpy(pad_buf, buf, nb_sectors * BDRV_SECTOR_SIZE);
+            ret = qcow2_write_compressed(bs, sector_num,
+                                         pad_buf, s->cluster_sectors);
+            qemu_vfree(pad_buf);
+        }
+        return ret;
+    }
+
+    out_buf = g_malloc(s->cluster_size + (s->cluster_size / 1000) + 128);
+
+    /* best compression, small window, no zlib header */
+    memset(&strm, 0, sizeof(strm));
+    ret = deflateInit2(&strm, Z_DEFAULT_COMPRESSION,
+                       Z_DEFLATED, -12,
+                       9, Z_DEFAULT_STRATEGY);
+    if (ret != 0) {
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    strm.avail_in = s->cluster_size;
+    strm.next_in = (uint8_t *)buf;
+    strm.avail_out = s->cluster_size;
+    strm.next_out = out_buf;
+
+    ret = deflate(&strm, Z_FINISH);
+    if (ret != Z_STREAM_END && ret != Z_OK) {
+        deflateEnd(&strm);
+        ret = -EINVAL;
+        goto fail;
+    }
+    out_len = strm.next_out - out_buf;
+
+    deflateEnd(&strm);
+
+    if (ret != Z_STREAM_END || out_len >= s->cluster_size) {
+        /* could not compress: write normal cluster */
+        ret = bdrv_write(bs, sector_num, buf, s->cluster_sectors);
+        if (ret < 0) {
+            goto fail;
+        }
+    } else {
+        cluster_offset = qcow2_alloc_compressed_cluster_offset(bs,
+            sector_num << 9, out_len);
+        if (!cluster_offset) {
+            ret = -EIO;
+            goto fail;
+        }
+        cluster_offset &= s->cluster_offset_mask;
+        BLKDBG_EVENT(bs->file, BLKDBG_WRITE_COMPRESSED);
+        ret = bdrv_pwrite(bs->file, cluster_offset, out_buf, out_len);
+        if (ret < 0) {
+            goto fail;
+        }
+    }
+
+    ret = 0;
+fail:
+    g_free(out_buf);
+    return ret;
+}
+
+static coroutine_fn int qcow2_co_flush_to_os(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    int ret;
+
+    qemu_co_mutex_lock(&s->lock);
+    ret = qcow2_cache_flush(bs, s->l2_table_cache);
+    if (ret < 0) {
+        qemu_co_mutex_unlock(&s->lock);
+        return ret;
+    }
+
+    if (qcow2_need_accurate_refcounts(s)) {
+        ret = qcow2_cache_flush(bs, s->refcount_block_cache);
+        if (ret < 0) {
+            qemu_co_mutex_unlock(&s->lock);
+            return ret;
+        }
+    }
+    qemu_co_mutex_unlock(&s->lock);
+
+    return 0;
+}
+
+static int64_t qcow2_vm_state_offset(BDRVQcowState *s)
+{
+	return (int64_t)s->l1_vm_state_index << (s->cluster_bits + s->l2_bits);
+}
+
+static int qcow2_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+    BDRVQcowState *s = bs->opaque;
+    bdi->cluster_size = s->cluster_size;
+    bdi->vm_state_offset = qcow2_vm_state_offset(s);
+    return 0;
+}
+
+#if 0
+static void dump_refcounts(BlockDriverState *bs)
+{
+    BDRVQcowState *s = bs->opaque;
+    int64_t nb_clusters, k, k1, size;
+    int refcount;
+
+    size = bdrv_getlength(bs->file);
+    nb_clusters = size_to_clusters(s, size);
+    for(k = 0; k < nb_clusters;) {
+        k1 = k;
+        refcount = get_refcount(bs, k);
+        k++;
+        while (k < nb_clusters && get_refcount(bs, k) == refcount)
+            k++;
+        printf("%" PRId64 ": refcount=%d nb=%" PRId64 "\n", k, refcount,
+               k - k1);
+    }
+}
+#endif
+
+static int qcow2_save_vmstate(BlockDriverState *bs, QEMUIOVector *qiov,
+                              int64_t pos)
+{
+    BDRVQcowState *s = bs->opaque;
+    int growable = bs->growable;
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_SAVE);
+    bs->growable = 1;
+    ret = bdrv_pwritev(bs, qcow2_vm_state_offset(s) + pos, qiov);
+    bs->growable = growable;
+
+    return ret;
+}
+
+static int qcow2_load_vmstate(BlockDriverState *bs, uint8_t *buf,
+                              int64_t pos, int size)
+{
+    BDRVQcowState *s = bs->opaque;
+    int growable = bs->growable;
+    int ret;
+
+    BLKDBG_EVENT(bs->file, BLKDBG_VMSTATE_LOAD);
+    bs->growable = 1;
+    ret = bdrv_pread(bs, qcow2_vm_state_offset(s) + pos, buf, size);
+    bs->growable = growable;
+
+    return ret;
+}
+
+static QEMUOptionParameter qcow2_create_options[] = {
+    {
+        .name = BLOCK_OPT_SIZE,
+        .type = OPT_SIZE,
+        .help = "Virtual disk size"
+    },
+    {
+        .name = BLOCK_OPT_COMPAT_LEVEL,
+        .type = OPT_STRING,
+        .help = "Compatibility level (0.10 or 1.1)"
+    },
+    {
+        .name = BLOCK_OPT_BACKING_FILE,
+        .type = OPT_STRING,
+        .help = "File name of a base image"
+    },
+    {
+        .name = BLOCK_OPT_BACKING_FMT,
+        .type = OPT_STRING,
+        .help = "Image format of the base image"
+    },
+    {
+        .name = BLOCK_OPT_ENCRYPT,
+        .type = OPT_FLAG,
+        .help = "Encrypt the image"
+    },
+    {
+        .name = BLOCK_OPT_CLUSTER_SIZE,
+        .type = OPT_SIZE,
+        .help = "qcow2 cluster size",
+        .value = { .n = DEFAULT_CLUSTER_SIZE },
+    },
+    {
+        .name = BLOCK_OPT_PREALLOC,
+        .type = OPT_STRING,
+        .help = "Preallocation mode (allowed values: off, metadata)"
+    },
+    {
+        .name = BLOCK_OPT_LAZY_REFCOUNTS,
+        .type = OPT_FLAG,
+        .help = "Postpone refcount updates",
+    },
+    { NULL }
+};
+
+static BlockDriver bdrv_qcow2 = {
+    .format_name        = "qcow2",
+    .instance_size      = sizeof(BDRVQcowState),
+    .bdrv_probe         = qcow2_probe,
+    .bdrv_open          = qcow2_open,
+    .bdrv_close         = qcow2_close,
+    .bdrv_reopen_prepare  = qcow2_reopen_prepare,
+    .bdrv_create        = qcow2_create,
+    .bdrv_has_zero_init = bdrv_has_zero_init_1,
+    .bdrv_co_is_allocated = qcow2_co_is_allocated,
+    .bdrv_set_key       = qcow2_set_key,
+    .bdrv_make_empty    = qcow2_make_empty,
+
+    .bdrv_co_readv          = qcow2_co_readv,
+    .bdrv_co_writev         = qcow2_co_writev,
+    .bdrv_co_flush_to_os    = qcow2_co_flush_to_os,
+
+    .bdrv_co_write_zeroes   = qcow2_co_write_zeroes,
+    .bdrv_co_discard        = qcow2_co_discard,
+    .bdrv_truncate          = qcow2_truncate,
+    .bdrv_write_compressed  = qcow2_write_compressed,
+
+    .bdrv_snapshot_create   = qcow2_snapshot_create,
+    .bdrv_snapshot_goto     = qcow2_snapshot_goto,
+    .bdrv_snapshot_delete   = qcow2_snapshot_delete,
+    .bdrv_snapshot_list     = qcow2_snapshot_list,
+    .bdrv_snapshot_load_tmp     = qcow2_snapshot_load_tmp,
+    .bdrv_get_info      = qcow2_get_info,
+
+    .bdrv_save_vmstate    = qcow2_save_vmstate,
+    .bdrv_load_vmstate    = qcow2_load_vmstate,
+
+    .bdrv_change_backing_file   = qcow2_change_backing_file,
+
+    .bdrv_invalidate_cache      = qcow2_invalidate_cache,
+
+    .create_options = qcow2_create_options,
+    .bdrv_check = qcow2_check,
+};
+
+static void bdrv_qcow2_init(void)
+{
+    bdrv_register(&bdrv_qcow2);
+}
+
+block_init(bdrv_qcow2_init);
diff --git a/contrib/qemu/block/qcow2.h b/contrib/qemu/block/qcow2.h
new file mode 100644
index 000000000..3b2d5cda7
--- /dev/null
+++ b/contrib/qemu/block/qcow2.h
@@ -0,0 +1,437 @@
+/*
+ * Block driver for the QCOW version 2 format
+ *
+ * Copyright (c) 2004-2006 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef BLOCK_QCOW2_H
+#define BLOCK_QCOW2_H
+
+#include "qemu/aes.h"
+#include "block/coroutine.h"
+
+//#define DEBUG_ALLOC
+//#define DEBUG_ALLOC2
+//#define DEBUG_EXT
+
+#define QCOW_MAGIC (('Q' << 24) | ('F' << 16) | ('I' << 8) | 0xfb)
+
+#define QCOW_CRYPT_NONE 0
+#define QCOW_CRYPT_AES  1
+
+#define QCOW_MAX_CRYPT_CLUSTERS 32
+
+/* indicate that the refcount of the referenced cluster is exactly one. */
+#define QCOW_OFLAG_COPIED     (1LL << 63)
+/* indicate that the cluster is compressed (they never have the copied flag) */
+#define QCOW_OFLAG_COMPRESSED (1LL << 62)
+/* The cluster reads as all zeros */
+#define QCOW_OFLAG_ZERO (1LL << 0)
+
+#define REFCOUNT_SHIFT 1 /* refcount size is 2 bytes */
+
+#define MIN_CLUSTER_BITS 9
+#define MAX_CLUSTER_BITS 21
+
+#define L2_CACHE_SIZE 16
+
+/* Must be at least 4 to cover all cases of refcount table growth */
+#define REFCOUNT_CACHE_SIZE 4
+
+#define DEFAULT_CLUSTER_SIZE 65536
+
+
+#define QCOW2_OPT_LAZY_REFCOUNTS "lazy_refcounts"
+#define QCOW2_OPT_DISCARD_REQUEST "pass_discard_request"
+#define QCOW2_OPT_DISCARD_SNAPSHOT "pass_discard_snapshot"
+#define QCOW2_OPT_DISCARD_OTHER "pass_discard_other"
+
+typedef struct QCowHeader {
+    uint32_t magic;
+    uint32_t version;
+    uint64_t backing_file_offset;
+    uint32_t backing_file_size;
+    uint32_t cluster_bits;
+    uint64_t size; /* in bytes */
+    uint32_t crypt_method;
+    uint32_t l1_size; /* XXX: save number of clusters instead ? */
+    uint64_t l1_table_offset;
+    uint64_t refcount_table_offset;
+    uint32_t refcount_table_clusters;
+    uint32_t nb_snapshots;
+    uint64_t snapshots_offset;
+
+    /* The following fields are only valid for version >= 3 */
+    uint64_t incompatible_features;
+    uint64_t compatible_features;
+    uint64_t autoclear_features;
+
+    uint32_t refcount_order;
+    uint32_t header_length;
+} QCowHeader;
+
+typedef struct QCowSnapshot {
+    uint64_t l1_table_offset;
+    uint32_t l1_size;
+    char *id_str;
+    char *name;
+    uint64_t disk_size;
+    uint64_t vm_state_size;
+    uint32_t date_sec;
+    uint32_t date_nsec;
+    uint64_t vm_clock_nsec;
+} QCowSnapshot;
+
+struct Qcow2Cache;
+typedef struct Qcow2Cache Qcow2Cache;
+
+typedef struct Qcow2UnknownHeaderExtension {
+    uint32_t magic;
+    uint32_t len;
+    QLIST_ENTRY(Qcow2UnknownHeaderExtension) next;
+    uint8_t data[];
+} Qcow2UnknownHeaderExtension;
+
+enum {
+    QCOW2_FEAT_TYPE_INCOMPATIBLE    = 0,
+    QCOW2_FEAT_TYPE_COMPATIBLE      = 1,
+    QCOW2_FEAT_TYPE_AUTOCLEAR       = 2,
+};
+
+/* Incompatible feature bits */
+enum {
+    QCOW2_INCOMPAT_DIRTY_BITNR   = 0,
+    QCOW2_INCOMPAT_DIRTY         = 1 << QCOW2_INCOMPAT_DIRTY_BITNR,
+
+    QCOW2_INCOMPAT_MASK          = QCOW2_INCOMPAT_DIRTY,
+};
+
+/* Compatible feature bits */
+enum {
+    QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR = 0,
+    QCOW2_COMPAT_LAZY_REFCOUNTS       = 1 << QCOW2_COMPAT_LAZY_REFCOUNTS_BITNR,
+
+    QCOW2_COMPAT_FEAT_MASK            = QCOW2_COMPAT_LAZY_REFCOUNTS,
+};
+
+enum qcow2_discard_type {
+    QCOW2_DISCARD_NEVER = 0,
+    QCOW2_DISCARD_ALWAYS,
+    QCOW2_DISCARD_REQUEST,
+    QCOW2_DISCARD_SNAPSHOT,
+    QCOW2_DISCARD_OTHER,
+    QCOW2_DISCARD_MAX
+};
+
+typedef struct Qcow2Feature {
+    uint8_t type;
+    uint8_t bit;
+    char    name[46];
+} QEMU_PACKED Qcow2Feature;
+
+typedef struct Qcow2DiscardRegion {
+    BlockDriverState *bs;
+    uint64_t offset;
+    uint64_t bytes;
+    QTAILQ_ENTRY(Qcow2DiscardRegion) next;
+} Qcow2DiscardRegion;
+
+typedef struct BDRVQcowState {
+    int cluster_bits;
+    int cluster_size;
+    int cluster_sectors;
+    int l2_bits;
+    int l2_size;
+    int l1_size;
+    int l1_vm_state_index;
+    int csize_shift;
+    int csize_mask;
+    uint64_t cluster_offset_mask;
+    uint64_t l1_table_offset;
+    uint64_t *l1_table;
+
+    Qcow2Cache* l2_table_cache;
+    Qcow2Cache* refcount_block_cache;
+
+    uint8_t *cluster_cache;
+    uint8_t *cluster_data;
+    uint64_t cluster_cache_offset;
+    QLIST_HEAD(QCowClusterAlloc, QCowL2Meta) cluster_allocs;
+
+    uint64_t *refcount_table;
+    uint64_t refcount_table_offset;
+    uint32_t refcount_table_size;
+    int64_t free_cluster_index;
+    int64_t free_byte_offset;
+
+    CoMutex lock;
+
+    uint32_t crypt_method; /* current crypt method, 0 if no key yet */
+    uint32_t crypt_method_header;
+    AES_KEY aes_encrypt_key;
+    AES_KEY aes_decrypt_key;
+    uint64_t snapshots_offset;
+    int snapshots_size;
+    int nb_snapshots;
+    QCowSnapshot *snapshots;
+
+    int flags;
+    int qcow_version;
+    bool use_lazy_refcounts;
+
+    bool discard_passthrough[QCOW2_DISCARD_MAX];
+
+    uint64_t incompatible_features;
+    uint64_t compatible_features;
+    uint64_t autoclear_features;
+
+    size_t unknown_header_fields_size;
+    void* unknown_header_fields;
+    QLIST_HEAD(, Qcow2UnknownHeaderExtension) unknown_header_ext;
+    QTAILQ_HEAD (, Qcow2DiscardRegion) discards;
+    bool cache_discards;
+} BDRVQcowState;
+
+/* XXX: use std qcow open function ? */
+typedef struct QCowCreateState {
+    int cluster_size;
+    int cluster_bits;
+    uint16_t *refcount_block;
+    uint64_t *refcount_table;
+    int64_t l1_table_offset;
+    int64_t refcount_table_offset;
+    int64_t refcount_block_offset;
+} QCowCreateState;
+
+struct QCowAIOCB;
+
+typedef struct Qcow2COWRegion {
+    /**
+     * Offset of the COW region in bytes from the start of the first cluster
+     * touched by the request.
+     */
+    uint64_t    offset;
+
+    /** Number of sectors to copy */
+    int         nb_sectors;
+} Qcow2COWRegion;
+
+/**
+ * Describes an in-flight (part of a) write request that writes to clusters
+ * that are not referenced in their L2 table yet.
+ */
+typedef struct QCowL2Meta
+{
+    /** Guest offset of the first newly allocated cluster */
+    uint64_t offset;
+
+    /** Host offset of the first newly allocated cluster */
+    uint64_t alloc_offset;
+
+    /**
+     * Number of sectors from the start of the first allocated cluster to
+     * the end of the (possibly shortened) request
+     */
+    int nb_available;
+
+    /** Number of newly allocated clusters */
+    int nb_clusters;
+
+    /**
+     * Requests that overlap with this allocation and wait to be restarted
+     * when the allocating request has completed.
+     */
+    CoQueue dependent_requests;
+
+    /**
+     * The COW Region between the start of the first allocated cluster and the
+     * area the guest actually writes to.
+     */
+    Qcow2COWRegion cow_start;
+
+    /**
+     * The COW Region between the area the guest actually writes to and the
+     * end of the last allocated cluster.
+     */
+    Qcow2COWRegion cow_end;
+
+    /** Pointer to next L2Meta of the same write request */
+    struct QCowL2Meta *next;
+
+    QLIST_ENTRY(QCowL2Meta) next_in_flight;
+} QCowL2Meta;
+
+enum {
+    QCOW2_CLUSTER_UNALLOCATED,
+    QCOW2_CLUSTER_NORMAL,
+    QCOW2_CLUSTER_COMPRESSED,
+    QCOW2_CLUSTER_ZERO
+};
+
+#define L1E_OFFSET_MASK 0x00ffffffffffff00ULL
+#define L2E_OFFSET_MASK 0x00ffffffffffff00ULL
+#define L2E_COMPRESSED_OFFSET_SIZE_MASK 0x3fffffffffffffffULL
+
+#define REFT_OFFSET_MASK 0xffffffffffffff00ULL
+
+static inline int64_t start_of_cluster(BDRVQcowState *s, int64_t offset)
+{
+    return offset & ~(s->cluster_size - 1);
+}
+
+static inline int64_t offset_into_cluster(BDRVQcowState *s, int64_t offset)
+{
+    return offset & (s->cluster_size - 1);
+}
+
+static inline int size_to_clusters(BDRVQcowState *s, int64_t size)
+{
+    return (size + (s->cluster_size - 1)) >> s->cluster_bits;
+}
+
+static inline int64_t size_to_l1(BDRVQcowState *s, int64_t size)
+{
+    int shift = s->cluster_bits + s->l2_bits;
+    return (size + (1ULL << shift) - 1) >> shift;
+}
+
+static inline int offset_to_l2_index(BDRVQcowState *s, int64_t offset)
+{
+    return (offset >> s->cluster_bits) & (s->l2_size - 1);
+}
+
+static inline int64_t align_offset(int64_t offset, int n)
+{
+    offset = (offset + n - 1) & ~(n - 1);
+    return offset;
+}
+
+static inline int qcow2_get_cluster_type(uint64_t l2_entry)
+{
+    if (l2_entry & QCOW_OFLAG_COMPRESSED) {
+        return QCOW2_CLUSTER_COMPRESSED;
+    } else if (l2_entry & QCOW_OFLAG_ZERO) {
+        return QCOW2_CLUSTER_ZERO;
+    } else if (!(l2_entry & L2E_OFFSET_MASK)) {
+        return QCOW2_CLUSTER_UNALLOCATED;
+    } else {
+        return QCOW2_CLUSTER_NORMAL;
+    }
+}
+
+/* Check whether refcounts are eager or lazy */
+static inline bool qcow2_need_accurate_refcounts(BDRVQcowState *s)
+{
+    return !(s->incompatible_features & QCOW2_INCOMPAT_DIRTY);
+}
+
+static inline uint64_t l2meta_cow_start(QCowL2Meta *m)
+{
+    return m->offset + m->cow_start.offset;
+}
+
+static inline uint64_t l2meta_cow_end(QCowL2Meta *m)
+{
+    return m->offset + m->cow_end.offset
+        + (m->cow_end.nb_sectors << BDRV_SECTOR_BITS);
+}
+
+// FIXME Need qcow2_ prefix to global functions
+
+/* qcow2.c functions */
+int qcow2_backing_read1(BlockDriverState *bs, QEMUIOVector *qiov,
+                  int64_t sector_num, int nb_sectors);
+
+int qcow2_mark_dirty(BlockDriverState *bs);
+int qcow2_update_header(BlockDriverState *bs);
+
+/* qcow2-refcount.c functions */
+int qcow2_refcount_init(BlockDriverState *bs);
+void qcow2_refcount_close(BlockDriverState *bs);
+
+int64_t qcow2_alloc_clusters(BlockDriverState *bs, int64_t size);
+int qcow2_alloc_clusters_at(BlockDriverState *bs, uint64_t offset,
+    int nb_clusters);
+int64_t qcow2_alloc_bytes(BlockDriverState *bs, int size);
+void qcow2_free_clusters(BlockDriverState *bs,
+                          int64_t offset, int64_t size,
+                          enum qcow2_discard_type type);
+void qcow2_free_any_clusters(BlockDriverState *bs, uint64_t l2_entry,
+                             int nb_clusters, enum qcow2_discard_type type);
+
+int qcow2_update_snapshot_refcount(BlockDriverState *bs,
+    int64_t l1_table_offset, int l1_size, int addend);
+
+int qcow2_check_refcounts(BlockDriverState *bs, BdrvCheckResult *res,
+                          BdrvCheckMode fix);
+
+void qcow2_process_discards(BlockDriverState *bs, int ret);
+
+/* qcow2-cluster.c functions */
+int qcow2_grow_l1_table(BlockDriverState *bs, uint64_t min_size,
+                        bool exact_size);
+void qcow2_l2_cache_reset(BlockDriverState *bs);
+int qcow2_decompress_cluster(BlockDriverState *bs, uint64_t cluster_offset);
+void qcow2_encrypt_sectors(BDRVQcowState *s, int64_t sector_num,
+                     uint8_t *out_buf, const uint8_t *in_buf,
+                     int nb_sectors, int enc,
+                     const AES_KEY *key);
+
+int qcow2_get_cluster_offset(BlockDriverState *bs, uint64_t offset,
+    int *num, uint64_t *cluster_offset);
+int qcow2_alloc_cluster_offset(BlockDriverState *bs, uint64_t offset,
+    int n_start, int n_end, int *num, uint64_t *host_offset, QCowL2Meta **m);
+uint64_t qcow2_alloc_compressed_cluster_offset(BlockDriverState *bs,
+                                         uint64_t offset,
+                                         int compressed_size);
+
+int qcow2_alloc_cluster_link_l2(BlockDriverState *bs, QCowL2Meta *m);
+int qcow2_discard_clusters(BlockDriverState *bs, uint64_t offset,
+    int nb_sectors);
+int qcow2_zero_clusters(BlockDriverState *bs, uint64_t offset, int nb_sectors);
+
+/* qcow2-snapshot.c functions */
+int qcow2_snapshot_create(BlockDriverState *bs, QEMUSnapshotInfo *sn_info);
+int qcow2_snapshot_goto(BlockDriverState *bs, const char *snapshot_id);
+int qcow2_snapshot_delete(BlockDriverState *bs, const char *snapshot_id);
+int qcow2_snapshot_list(BlockDriverState *bs, QEMUSnapshotInfo **psn_tab);
+int qcow2_snapshot_load_tmp(BlockDriverState *bs, const char *snapshot_name);
+
+void qcow2_free_snapshots(BlockDriverState *bs);
+int qcow2_read_snapshots(BlockDriverState *bs);
+
+/* qcow2-cache.c functions */
+Qcow2Cache *qcow2_cache_create(BlockDriverState *bs, int num_tables);
+int qcow2_cache_destroy(BlockDriverState* bs, Qcow2Cache *c);
+
+void qcow2_cache_entry_mark_dirty(Qcow2Cache *c, void *table);
+int qcow2_cache_flush(BlockDriverState *bs, Qcow2Cache *c);
+int qcow2_cache_set_dependency(BlockDriverState *bs, Qcow2Cache *c,
+    Qcow2Cache *dependency);
+void qcow2_cache_depends_on_flush(Qcow2Cache *c);
+
+int qcow2_cache_get(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table);
+int qcow2_cache_get_empty(BlockDriverState *bs, Qcow2Cache *c, uint64_t offset,
+    void **table);
+int qcow2_cache_put(BlockDriverState *bs, Qcow2Cache *c, void **table);
+
+#endif
diff --git a/contrib/qemu/block/qed-check.c b/contrib/qemu/block/qed-check.c
new file mode 100644
index 000000000..b473dcd61
--- /dev/null
+++ b/contrib/qemu/block/qed-check.c
@@ -0,0 +1,248 @@
+/*
+ * QEMU Enhanced Disk Format Consistency Check
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qed.h"
+
+typedef struct {
+    BDRVQEDState *s;
+    BdrvCheckResult *result;
+    bool fix;                           /* whether to fix invalid offsets */
+
+    uint64_t nclusters;
+    uint32_t *used_clusters;            /* referenced cluster bitmap */
+
+    QEDRequest request;
+} QEDCheck;
+
+static bool qed_test_bit(uint32_t *bitmap, uint64_t n) {
+    return !!(bitmap[n / 32] & (1 << (n % 32)));
+}
+
+static void qed_set_bit(uint32_t *bitmap, uint64_t n) {
+    bitmap[n / 32] |= 1 << (n % 32);
+}
+
+/**
+ * Set bitmap bits for clusters
+ *
+ * @check:          Check structure
+ * @offset:         Starting offset in bytes
+ * @n:              Number of clusters
+ */
+static bool qed_set_used_clusters(QEDCheck *check, uint64_t offset,
+                                  unsigned int n)
+{
+    uint64_t cluster = qed_bytes_to_clusters(check->s, offset);
+    unsigned int corruptions = 0;
+
+    while (n-- != 0) {
+        /* Clusters should only be referenced once */
+        if (qed_test_bit(check->used_clusters, cluster)) {
+            corruptions++;
+        }
+
+        qed_set_bit(check->used_clusters, cluster);
+        cluster++;
+    }
+
+    check->result->corruptions += corruptions;
+    return corruptions == 0;
+}
+
+/**
+ * Check an L2 table
+ *
+ * @ret:            Number of invalid cluster offsets
+ */
+static unsigned int qed_check_l2_table(QEDCheck *check, QEDTable *table)
+{
+    BDRVQEDState *s = check->s;
+    unsigned int i, num_invalid = 0;
+    uint64_t last_offset = 0;
+
+    for (i = 0; i < s->table_nelems; i++) {
+        uint64_t offset = table->offsets[i];
+
+        if (qed_offset_is_unalloc_cluster(offset) ||
+            qed_offset_is_zero_cluster(offset)) {
+            continue;
+        }
+        check->result->bfi.allocated_clusters++;
+        if (last_offset && (last_offset + s->header.cluster_size != offset)) {
+            check->result->bfi.fragmented_clusters++;
+        }
+        last_offset = offset;
+
+        /* Detect invalid cluster offset */
+        if (!qed_check_cluster_offset(s, offset)) {
+            if (check->fix) {
+                table->offsets[i] = 0;
+                check->result->corruptions_fixed++;
+            } else {
+                check->result->corruptions++;
+            }
+
+            num_invalid++;
+            continue;
+        }
+
+        qed_set_used_clusters(check, offset, 1);
+    }
+
+    return num_invalid;
+}
+
+/**
+ * Descend tables and check each cluster is referenced once only
+ */
+static int qed_check_l1_table(QEDCheck *check, QEDTable *table)
+{
+    BDRVQEDState *s = check->s;
+    unsigned int i, num_invalid_l1 = 0;
+    int ret, last_error = 0;
+
+    /* Mark L1 table clusters used */
+    qed_set_used_clusters(check, s->header.l1_table_offset,
+                          s->header.table_size);
+
+    for (i = 0; i < s->table_nelems; i++) {
+        unsigned int num_invalid_l2;
+        uint64_t offset = table->offsets[i];
+
+        if (qed_offset_is_unalloc_cluster(offset)) {
+            continue;
+        }
+
+        /* Detect invalid L2 offset */
+        if (!qed_check_table_offset(s, offset)) {
+            /* Clear invalid offset */
+            if (check->fix) {
+                table->offsets[i] = 0;
+                check->result->corruptions_fixed++;
+            } else {
+                check->result->corruptions++;
+            }
+
+            num_invalid_l1++;
+            continue;
+        }
+
+        if (!qed_set_used_clusters(check, offset, s->header.table_size)) {
+            continue; /* skip an invalid table */
+        }
+
+        ret = qed_read_l2_table_sync(s, &check->request, offset);
+        if (ret) {
+            check->result->check_errors++;
+            last_error = ret;
+            continue;
+        }
+
+        num_invalid_l2 = qed_check_l2_table(check,
+                                            check->request.l2_table->table);
+
+        /* Write out fixed L2 table */
+        if (num_invalid_l2 > 0 && check->fix) {
+            ret = qed_write_l2_table_sync(s, &check->request, 0,
+                                          s->table_nelems, false);
+            if (ret) {
+                check->result->check_errors++;
+                last_error = ret;
+                continue;
+            }
+        }
+    }
+
+    /* Drop reference to final table */
+    qed_unref_l2_cache_entry(check->request.l2_table);
+    check->request.l2_table = NULL;
+
+    /* Write out fixed L1 table */
+    if (num_invalid_l1 > 0 && check->fix) {
+        ret = qed_write_l1_table_sync(s, 0, s->table_nelems);
+        if (ret) {
+            check->result->check_errors++;
+            last_error = ret;
+        }
+    }
+
+    return last_error;
+}
+
+/**
+ * Check for unreferenced (leaked) clusters
+ */
+static void qed_check_for_leaks(QEDCheck *check)
+{
+    BDRVQEDState *s = check->s;
+    uint64_t i;
+
+    for (i = s->header.header_size; i < check->nclusters; i++) {
+        if (!qed_test_bit(check->used_clusters, i)) {
+            check->result->leaks++;
+        }
+    }
+}
+
+/**
+ * Mark an image clean once it passes check or has been repaired
+ */
+static void qed_check_mark_clean(BDRVQEDState *s, BdrvCheckResult *result)
+{
+    /* Skip if there were unfixable corruptions or I/O errors */
+    if (result->corruptions > 0 || result->check_errors > 0) {
+        return;
+    }
+
+    /* Skip if image is already marked clean */
+    if (!(s->header.features & QED_F_NEED_CHECK)) {
+        return;
+    }
+
+    /* Ensure fixes reach storage before clearing check bit */
+    bdrv_flush(s->bs);
+
+    s->header.features &= ~QED_F_NEED_CHECK;
+    qed_write_header_sync(s);
+}
+
+int qed_check(BDRVQEDState *s, BdrvCheckResult *result, bool fix)
+{
+    QEDCheck check = {
+        .s = s,
+        .result = result,
+        .nclusters = qed_bytes_to_clusters(s, s->file_size),
+        .request = { .l2_table = NULL },
+        .fix = fix,
+    };
+    int ret;
+
+    check.used_clusters = g_malloc0(((check.nclusters + 31) / 32) *
+                                       sizeof(check.used_clusters[0]));
+
+    check.result->bfi.total_clusters =
+        (s->header.image_size + s->header.cluster_size - 1) /
+            s->header.cluster_size;
+    ret = qed_check_l1_table(&check, s->l1_table);
+    if (ret == 0) {
+        /* Only check for leaks if entire image was scanned successfully */
+        qed_check_for_leaks(&check);
+
+        if (fix) {
+            qed_check_mark_clean(s, result);
+        }
+    }
+
+    g_free(check.used_clusters);
+    return ret;
+}
diff --git a/contrib/qemu/block/qed-cluster.c b/contrib/qemu/block/qed-cluster.c
new file mode 100644
index 000000000..f64b2af8f
--- /dev/null
+++ b/contrib/qemu/block/qed-cluster.c
@@ -0,0 +1,165 @@
+/*
+ * QEMU Enhanced Disk Format Cluster functions
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qed.h"
+
+/**
+ * Count the number of contiguous data clusters
+ *
+ * @s:              QED state
+ * @table:          L2 table
+ * @index:          First cluster index
+ * @n:              Maximum number of clusters
+ * @offset:         Set to first cluster offset
+ *
+ * This function scans tables for contiguous clusters.  A contiguous run of
+ * clusters may be allocated, unallocated, or zero.
+ */
+static unsigned int qed_count_contiguous_clusters(BDRVQEDState *s,
+                                                  QEDTable *table,
+                                                  unsigned int index,
+                                                  unsigned int n,
+                                                  uint64_t *offset)
+{
+    unsigned int end = MIN(index + n, s->table_nelems);
+    uint64_t last = table->offsets[index];
+    unsigned int i;
+
+    *offset = last;
+
+    for (i = index + 1; i < end; i++) {
+        if (qed_offset_is_unalloc_cluster(last)) {
+            /* Counting unallocated clusters */
+            if (!qed_offset_is_unalloc_cluster(table->offsets[i])) {
+                break;
+            }
+        } else if (qed_offset_is_zero_cluster(last)) {
+            /* Counting zero clusters */
+            if (!qed_offset_is_zero_cluster(table->offsets[i])) {
+                break;
+            }
+        } else {
+            /* Counting allocated clusters */
+            if (table->offsets[i] != last + s->header.cluster_size) {
+                break;
+            }
+            last = table->offsets[i];
+        }
+    }
+    return i - index;
+}
+
+typedef struct {
+    BDRVQEDState *s;
+    uint64_t pos;
+    size_t len;
+
+    QEDRequest *request;
+
+    /* User callback */
+    QEDFindClusterFunc *cb;
+    void *opaque;
+} QEDFindClusterCB;
+
+static void qed_find_cluster_cb(void *opaque, int ret)
+{
+    QEDFindClusterCB *find_cluster_cb = opaque;
+    BDRVQEDState *s = find_cluster_cb->s;
+    QEDRequest *request = find_cluster_cb->request;
+    uint64_t offset = 0;
+    size_t len = 0;
+    unsigned int index;
+    unsigned int n;
+
+    if (ret) {
+        goto out;
+    }
+
+    index = qed_l2_index(s, find_cluster_cb->pos);
+    n = qed_bytes_to_clusters(s,
+                              qed_offset_into_cluster(s, find_cluster_cb->pos) +
+                              find_cluster_cb->len);
+    n = qed_count_contiguous_clusters(s, request->l2_table->table,
+                                      index, n, &offset);
+
+    if (qed_offset_is_unalloc_cluster(offset)) {
+        ret = QED_CLUSTER_L2;
+    } else if (qed_offset_is_zero_cluster(offset)) {
+        ret = QED_CLUSTER_ZERO;
+    } else if (qed_check_cluster_offset(s, offset)) {
+        ret = QED_CLUSTER_FOUND;
+    } else {
+        ret = -EINVAL;
+    }
+
+    len = MIN(find_cluster_cb->len, n * s->header.cluster_size -
+              qed_offset_into_cluster(s, find_cluster_cb->pos));
+
+out:
+    find_cluster_cb->cb(find_cluster_cb->opaque, ret, offset, len);
+    g_free(find_cluster_cb);
+}
+
+/**
+ * Find the offset of a data cluster
+ *
+ * @s:          QED state
+ * @request:    L2 cache entry
+ * @pos:        Byte position in device
+ * @len:        Number of bytes
+ * @cb:         Completion function
+ * @opaque:     User data for completion function
+ *
+ * This function translates a position in the block device to an offset in the
+ * image file.  It invokes the cb completion callback to report back the
+ * translated offset or unallocated range in the image file.
+ *
+ * If the L2 table exists, request->l2_table points to the L2 table cache entry
+ * and the caller must free the reference when they are finished.  The cache
+ * entry is exposed in this way to avoid callers having to read the L2 table
+ * again later during request processing.  If request->l2_table is non-NULL it
+ * will be unreferenced before taking on the new cache entry.
+ */
+void qed_find_cluster(BDRVQEDState *s, QEDRequest *request, uint64_t pos,
+                      size_t len, QEDFindClusterFunc *cb, void *opaque)
+{
+    QEDFindClusterCB *find_cluster_cb;
+    uint64_t l2_offset;
+
+    /* Limit length to L2 boundary.  Requests are broken up at the L2 boundary
+     * so that a request acts on one L2 table at a time.
+     */
+    len = MIN(len, (((pos >> s->l1_shift) + 1) << s->l1_shift) - pos);
+
+    l2_offset = s->l1_table->offsets[qed_l1_index(s, pos)];
+    if (qed_offset_is_unalloc_cluster(l2_offset)) {
+        cb(opaque, QED_CLUSTER_L1, 0, len);
+        return;
+    }
+    if (!qed_check_table_offset(s, l2_offset)) {
+        cb(opaque, -EINVAL, 0, 0);
+        return;
+    }
+
+    find_cluster_cb = g_malloc(sizeof(*find_cluster_cb));
+    find_cluster_cb->s = s;
+    find_cluster_cb->pos = pos;
+    find_cluster_cb->len = len;
+    find_cluster_cb->cb = cb;
+    find_cluster_cb->opaque = opaque;
+    find_cluster_cb->request = request;
+
+    qed_read_l2_table(s, request, l2_offset,
+                      qed_find_cluster_cb, find_cluster_cb);
+}
diff --git a/contrib/qemu/block/qed-gencb.c b/contrib/qemu/block/qed-gencb.c
new file mode 100644
index 000000000..7d7ac1ffc
--- /dev/null
+++ b/contrib/qemu/block/qed-gencb.c
@@ -0,0 +1,32 @@
+/*
+ * QEMU Enhanced Disk Format
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qed.h"
+
+void *gencb_alloc(size_t len, BlockDriverCompletionFunc *cb, void *opaque)
+{
+    GenericCB *gencb = g_malloc(len);
+    gencb->cb = cb;
+    gencb->opaque = opaque;
+    return gencb;
+}
+
+void gencb_complete(void *opaque, int ret)
+{
+    GenericCB *gencb = opaque;
+    BlockDriverCompletionFunc *cb = gencb->cb;
+    void *user_opaque = gencb->opaque;
+
+    g_free(gencb);
+    cb(user_opaque, ret);
+}
diff --git a/contrib/qemu/block/qed-l2-cache.c b/contrib/qemu/block/qed-l2-cache.c
new file mode 100644
index 000000000..e9b2aae44
--- /dev/null
+++ b/contrib/qemu/block/qed-l2-cache.c
@@ -0,0 +1,187 @@
+/*
+ * QEMU Enhanced Disk Format L2 Cache
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+/*
+ * L2 table cache usage is as follows:
+ *
+ * An open image has one L2 table cache that is used to avoid accessing the
+ * image file for recently referenced L2 tables.
+ *
+ * Cluster offset lookup translates the logical offset within the block device
+ * to a cluster offset within the image file.  This is done by indexing into
+ * the L1 and L2 tables which store cluster offsets.  It is here where the L2
+ * table cache serves up recently referenced L2 tables.
+ *
+ * If there is a cache miss, that L2 table is read from the image file and
+ * committed to the cache.  Subsequent accesses to that L2 table will be served
+ * from the cache until the table is evicted from the cache.
+ *
+ * L2 tables are also committed to the cache when new L2 tables are allocated
+ * in the image file.  Since the L2 table cache is write-through, the new L2
+ * table is first written out to the image file and then committed to the
+ * cache.
+ *
+ * Multiple I/O requests may be using an L2 table cache entry at any given
+ * time.  That means an entry may be in use across several requests and
+ * reference counting is needed to free the entry at the correct time.  In
+ * particular, an entry evicted from the cache will only be freed once all
+ * references are dropped.
+ *
+ * An in-flight I/O request will hold a reference to a L2 table cache entry for
+ * the period during which it needs to access the L2 table.  This includes
+ * cluster offset lookup, L2 table allocation, and L2 table update when a new
+ * data cluster has been allocated.
+ *
+ * An interesting case occurs when two requests need to access an L2 table that
+ * is not in the cache.  Since the operation to read the table from the image
+ * file takes some time to complete, both requests may see a cache miss and
+ * start reading the L2 table from the image file.  The first to finish will
+ * commit its L2 table into the cache.  When the second tries to commit its
+ * table will be deleted in favor of the existing cache entry.
+ */
+
+#include "trace.h"
+#include "qed.h"
+
+/* Each L2 holds 2GB so this let's us fully cache a 100GB disk */
+#define MAX_L2_CACHE_SIZE 50
+
+/**
+ * Initialize the L2 cache
+ */
+void qed_init_l2_cache(L2TableCache *l2_cache)
+{
+    QTAILQ_INIT(&l2_cache->entries);
+    l2_cache->n_entries = 0;
+}
+
+/**
+ * Free the L2 cache
+ */
+void qed_free_l2_cache(L2TableCache *l2_cache)
+{
+    CachedL2Table *entry, *next_entry;
+
+    QTAILQ_FOREACH_SAFE(entry, &l2_cache->entries, node, next_entry) {
+        qemu_vfree(entry->table);
+        g_free(entry);
+    }
+}
+
+/**
+ * Allocate an uninitialized entry from the cache
+ *
+ * The returned entry has a reference count of 1 and is owned by the caller.
+ * The caller must allocate the actual table field for this entry and it must
+ * be freeable using qemu_vfree().
+ */
+CachedL2Table *qed_alloc_l2_cache_entry(L2TableCache *l2_cache)
+{
+    CachedL2Table *entry;
+
+    entry = g_malloc0(sizeof(*entry));
+    entry->ref++;
+
+    trace_qed_alloc_l2_cache_entry(l2_cache, entry);
+
+    return entry;
+}
+
+/**
+ * Decrease an entry's reference count and free if necessary when the reference
+ * count drops to zero.
+ */
+void qed_unref_l2_cache_entry(CachedL2Table *entry)
+{
+    if (!entry) {
+        return;
+    }
+
+    entry->ref--;
+    trace_qed_unref_l2_cache_entry(entry, entry->ref);
+    if (entry->ref == 0) {
+        qemu_vfree(entry->table);
+        g_free(entry);
+    }
+}
+
+/**
+ * Find an entry in the L2 cache.  This may return NULL and it's up to the
+ * caller to satisfy the cache miss.
+ *
+ * For a cached entry, this function increases the reference count and returns
+ * the entry.
+ */
+CachedL2Table *qed_find_l2_cache_entry(L2TableCache *l2_cache, uint64_t offset)
+{
+    CachedL2Table *entry;
+
+    QTAILQ_FOREACH(entry, &l2_cache->entries, node) {
+        if (entry->offset == offset) {
+            trace_qed_find_l2_cache_entry(l2_cache, entry, offset, entry->ref);
+            entry->ref++;
+            return entry;
+        }
+    }
+    return NULL;
+}
+
+/**
+ * Commit an L2 cache entry into the cache.  This is meant to be used as part of
+ * the process to satisfy a cache miss.  A caller would allocate an entry which
+ * is not actually in the L2 cache and then once the entry was valid and
+ * present on disk, the entry can be committed into the cache.
+ *
+ * Since the cache is write-through, it's important that this function is not
+ * called until the entry is present on disk and the L1 has been updated to
+ * point to the entry.
+ *
+ * N.B. This function steals a reference to the l2_table from the caller so the
+ * caller must obtain a new reference by issuing a call to
+ * qed_find_l2_cache_entry().
+ */
+void qed_commit_l2_cache_entry(L2TableCache *l2_cache, CachedL2Table *l2_table)
+{
+    CachedL2Table *entry;
+
+    entry = qed_find_l2_cache_entry(l2_cache, l2_table->offset);
+    if (entry) {
+        qed_unref_l2_cache_entry(entry);
+        qed_unref_l2_cache_entry(l2_table);
+        return;
+    }
+
+    /* Evict an unused cache entry so we have space.  If all entries are in use
+     * we can grow the cache temporarily and we try to shrink back down later.
+     */
+    if (l2_cache->n_entries >= MAX_L2_CACHE_SIZE) {
+        CachedL2Table *next;
+        QTAILQ_FOREACH_SAFE(entry, &l2_cache->entries, node, next) {
+            if (entry->ref > 1) {
+                continue;
+            }
+
+            QTAILQ_REMOVE(&l2_cache->entries, entry, node);
+            l2_cache->n_entries--;
+            qed_unref_l2_cache_entry(entry);
+
+            /* Stop evicting when we've shrunk back to max size */
+            if (l2_cache->n_entries < MAX_L2_CACHE_SIZE) {
+                break;
+            }
+        }
+    }
+
+    l2_cache->n_entries++;
+    QTAILQ_INSERT_TAIL(&l2_cache->entries, l2_table, node);
+}
diff --git a/contrib/qemu/block/qed-table.c b/contrib/qemu/block/qed-table.c
new file mode 100644
index 000000000..76d2dcccf
--- /dev/null
+++ b/contrib/qemu/block/qed-table.c
@@ -0,0 +1,296 @@
+/*
+ * QEMU Enhanced Disk Format Table I/O
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "trace.h"
+#include "qemu/sockets.h" /* for EINPROGRESS on Windows */
+#include "qed.h"
+
+typedef struct {
+    GenericCB gencb;
+    BDRVQEDState *s;
+    QEDTable *table;
+
+    struct iovec iov;
+    QEMUIOVector qiov;
+} QEDReadTableCB;
+
+static void qed_read_table_cb(void *opaque, int ret)
+{
+    QEDReadTableCB *read_table_cb = opaque;
+    QEDTable *table = read_table_cb->table;
+    int noffsets = read_table_cb->qiov.size / sizeof(uint64_t);
+    int i;
+
+    /* Handle I/O error */
+    if (ret) {
+        goto out;
+    }
+
+    /* Byteswap offsets */
+    for (i = 0; i < noffsets; i++) {
+        table->offsets[i] = le64_to_cpu(table->offsets[i]);
+    }
+
+out:
+    /* Completion */
+    trace_qed_read_table_cb(read_table_cb->s, read_table_cb->table, ret);
+    gencb_complete(&read_table_cb->gencb, ret);
+}
+
+static void qed_read_table(BDRVQEDState *s, uint64_t offset, QEDTable *table,
+                           BlockDriverCompletionFunc *cb, void *opaque)
+{
+    QEDReadTableCB *read_table_cb = gencb_alloc(sizeof(*read_table_cb),
+                                                cb, opaque);
+    QEMUIOVector *qiov = &read_table_cb->qiov;
+
+    trace_qed_read_table(s, offset, table);
+
+    read_table_cb->s = s;
+    read_table_cb->table = table;
+    read_table_cb->iov.iov_base = table->offsets,
+    read_table_cb->iov.iov_len = s->header.cluster_size * s->header.table_size,
+
+    qemu_iovec_init_external(qiov, &read_table_cb->iov, 1);
+    bdrv_aio_readv(s->bs->file, offset / BDRV_SECTOR_SIZE, qiov,
+                   qiov->size / BDRV_SECTOR_SIZE,
+                   qed_read_table_cb, read_table_cb);
+}
+
+typedef struct {
+    GenericCB gencb;
+    BDRVQEDState *s;
+    QEDTable *orig_table;
+    QEDTable *table;
+    bool flush;             /* flush after write? */
+
+    struct iovec iov;
+    QEMUIOVector qiov;
+} QEDWriteTableCB;
+
+static void qed_write_table_cb(void *opaque, int ret)
+{
+    QEDWriteTableCB *write_table_cb = opaque;
+
+    trace_qed_write_table_cb(write_table_cb->s,
+                             write_table_cb->orig_table,
+                             write_table_cb->flush,
+                             ret);
+
+    if (ret) {
+        goto out;
+    }
+
+    if (write_table_cb->flush) {
+        /* We still need to flush first */
+        write_table_cb->flush = false;
+        bdrv_aio_flush(write_table_cb->s->bs, qed_write_table_cb,
+                       write_table_cb);
+        return;
+    }
+
+out:
+    qemu_vfree(write_table_cb->table);
+    gencb_complete(&write_table_cb->gencb, ret);
+}
+
+/**
+ * Write out an updated part or all of a table
+ *
+ * @s:          QED state
+ * @offset:     Offset of table in image file, in bytes
+ * @table:      Table
+ * @index:      Index of first element
+ * @n:          Number of elements
+ * @flush:      Whether or not to sync to disk
+ * @cb:         Completion function
+ * @opaque:     Argument for completion function
+ */
+static void qed_write_table(BDRVQEDState *s, uint64_t offset, QEDTable *table,
+                            unsigned int index, unsigned int n, bool flush,
+                            BlockDriverCompletionFunc *cb, void *opaque)
+{
+    QEDWriteTableCB *write_table_cb;
+    unsigned int sector_mask = BDRV_SECTOR_SIZE / sizeof(uint64_t) - 1;
+    unsigned int start, end, i;
+    size_t len_bytes;
+
+    trace_qed_write_table(s, offset, table, index, n);
+
+    /* Calculate indices of the first and one after last elements */
+    start = index & ~sector_mask;
+    end = (index + n + sector_mask) & ~sector_mask;
+
+    len_bytes = (end - start) * sizeof(uint64_t);
+
+    write_table_cb = gencb_alloc(sizeof(*write_table_cb), cb, opaque);
+    write_table_cb->s = s;
+    write_table_cb->orig_table = table;
+    write_table_cb->flush = flush;
+    write_table_cb->table = qemu_blockalign(s->bs, len_bytes);
+    write_table_cb->iov.iov_base = write_table_cb->table->offsets;
+    write_table_cb->iov.iov_len = len_bytes;
+    qemu_iovec_init_external(&write_table_cb->qiov, &write_table_cb->iov, 1);
+
+    /* Byteswap table */
+    for (i = start; i < end; i++) {
+        uint64_t le_offset = cpu_to_le64(table->offsets[i]);
+        write_table_cb->table->offsets[i - start] = le_offset;
+    }
+
+    /* Adjust for offset into table */
+    offset += start * sizeof(uint64_t);
+
+    bdrv_aio_writev(s->bs->file, offset / BDRV_SECTOR_SIZE,
+                    &write_table_cb->qiov,
+                    write_table_cb->qiov.size / BDRV_SECTOR_SIZE,
+                    qed_write_table_cb, write_table_cb);
+}
+
+/**
+ * Propagate return value from async callback
+ */
+static void qed_sync_cb(void *opaque, int ret)
+{
+    *(int *)opaque = ret;
+}
+
+int qed_read_l1_table_sync(BDRVQEDState *s)
+{
+    int ret = -EINPROGRESS;
+
+    qed_read_table(s, s->header.l1_table_offset,
+                   s->l1_table, qed_sync_cb, &ret);
+    while (ret == -EINPROGRESS) {
+        qemu_aio_wait();
+    }
+
+    return ret;
+}
+
+void qed_write_l1_table(BDRVQEDState *s, unsigned int index, unsigned int n,
+                        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    BLKDBG_EVENT(s->bs->file, BLKDBG_L1_UPDATE);
+    qed_write_table(s, s->header.l1_table_offset,
+                    s->l1_table, index, n, false, cb, opaque);
+}
+
+int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int index,
+                            unsigned int n)
+{
+    int ret = -EINPROGRESS;
+
+    qed_write_l1_table(s, index, n, qed_sync_cb, &ret);
+    while (ret == -EINPROGRESS) {
+        qemu_aio_wait();
+    }
+
+    return ret;
+}
+
+typedef struct {
+    GenericCB gencb;
+    BDRVQEDState *s;
+    uint64_t l2_offset;
+    QEDRequest *request;
+} QEDReadL2TableCB;
+
+static void qed_read_l2_table_cb(void *opaque, int ret)
+{
+    QEDReadL2TableCB *read_l2_table_cb = opaque;
+    QEDRequest *request = read_l2_table_cb->request;
+    BDRVQEDState *s = read_l2_table_cb->s;
+    CachedL2Table *l2_table = request->l2_table;
+    uint64_t l2_offset = read_l2_table_cb->l2_offset;
+
+    if (ret) {
+        /* can't trust loaded L2 table anymore */
+        qed_unref_l2_cache_entry(l2_table);
+        request->l2_table = NULL;
+    } else {
+        l2_table->offset = l2_offset;
+
+        qed_commit_l2_cache_entry(&s->l2_cache, l2_table);
+
+        /* This is guaranteed to succeed because we just committed the entry
+         * to the cache.
+         */
+        request->l2_table = qed_find_l2_cache_entry(&s->l2_cache, l2_offset);
+        assert(request->l2_table != NULL);
+    }
+
+    gencb_complete(&read_l2_table_cb->gencb, ret);
+}
+
+void qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset,
+                       BlockDriverCompletionFunc *cb, void *opaque)
+{
+    QEDReadL2TableCB *read_l2_table_cb;
+
+    qed_unref_l2_cache_entry(request->l2_table);
+
+    /* Check for cached L2 entry */
+    request->l2_table = qed_find_l2_cache_entry(&s->l2_cache, offset);
+    if (request->l2_table) {
+        cb(opaque, 0);
+        return;
+    }
+
+    request->l2_table = qed_alloc_l2_cache_entry(&s->l2_cache);
+    request->l2_table->table = qed_alloc_table(s);
+
+    read_l2_table_cb = gencb_alloc(sizeof(*read_l2_table_cb), cb, opaque);
+    read_l2_table_cb->s = s;
+    read_l2_table_cb->l2_offset = offset;
+    read_l2_table_cb->request = request;
+
+    BLKDBG_EVENT(s->bs->file, BLKDBG_L2_LOAD);
+    qed_read_table(s, offset, request->l2_table->table,
+                   qed_read_l2_table_cb, read_l2_table_cb);
+}
+
+int qed_read_l2_table_sync(BDRVQEDState *s, QEDRequest *request, uint64_t offset)
+{
+    int ret = -EINPROGRESS;
+
+    qed_read_l2_table(s, request, offset, qed_sync_cb, &ret);
+    while (ret == -EINPROGRESS) {
+        qemu_aio_wait();
+    }
+
+    return ret;
+}
+
+void qed_write_l2_table(BDRVQEDState *s, QEDRequest *request,
+                        unsigned int index, unsigned int n, bool flush,
+                        BlockDriverCompletionFunc *cb, void *opaque)
+{
+    BLKDBG_EVENT(s->bs->file, BLKDBG_L2_UPDATE);
+    qed_write_table(s, request->l2_table->offset,
+                    request->l2_table->table, index, n, flush, cb, opaque);
+}
+
+int qed_write_l2_table_sync(BDRVQEDState *s, QEDRequest *request,
+                            unsigned int index, unsigned int n, bool flush)
+{
+    int ret = -EINPROGRESS;
+
+    qed_write_l2_table(s, request, index, n, flush, qed_sync_cb, &ret);
+    while (ret == -EINPROGRESS) {
+        qemu_aio_wait();
+    }
+
+    return ret;
+}
diff --git a/contrib/qemu/block/qed.c b/contrib/qemu/block/qed.c
new file mode 100644
index 000000000..f767b0528
--- /dev/null
+++ b/contrib/qemu/block/qed.c
@@ -0,0 +1,1596 @@
+/*
+ * QEMU Enhanced Disk Format
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#include "qemu/timer.h"
+#include "trace.h"
+#include "qed.h"
+#include "qapi/qmp/qerror.h"
+#include "migration/migration.h"
+
+static void qed_aio_cancel(BlockDriverAIOCB *blockacb)
+{
+    QEDAIOCB *acb = (QEDAIOCB *)blockacb;
+    bool finished = false;
+
+    /* Wait for the request to finish */
+    acb->finished = &finished;
+    while (!finished) {
+        qemu_aio_wait();
+    }
+}
+
+static const AIOCBInfo qed_aiocb_info = {
+    .aiocb_size         = sizeof(QEDAIOCB),
+    .cancel             = qed_aio_cancel,
+};
+
+static int bdrv_qed_probe(const uint8_t *buf, int buf_size,
+                          const char *filename)
+{
+    const QEDHeader *header = (const QEDHeader *)buf;
+
+    if (buf_size < sizeof(*header)) {
+        return 0;
+    }
+    if (le32_to_cpu(header->magic) != QED_MAGIC) {
+        return 0;
+    }
+    return 100;
+}
+
+/**
+ * Check whether an image format is raw
+ *
+ * @fmt:    Backing file format, may be NULL
+ */
+static bool qed_fmt_is_raw(const char *fmt)
+{
+    return fmt && strcmp(fmt, "raw") == 0;
+}
+
+static void qed_header_le_to_cpu(const QEDHeader *le, QEDHeader *cpu)
+{
+    cpu->magic = le32_to_cpu(le->magic);
+    cpu->cluster_size = le32_to_cpu(le->cluster_size);
+    cpu->table_size = le32_to_cpu(le->table_size);
+    cpu->header_size = le32_to_cpu(le->header_size);
+    cpu->features = le64_to_cpu(le->features);
+    cpu->compat_features = le64_to_cpu(le->compat_features);
+    cpu->autoclear_features = le64_to_cpu(le->autoclear_features);
+    cpu->l1_table_offset = le64_to_cpu(le->l1_table_offset);
+    cpu->image_size = le64_to_cpu(le->image_size);
+    cpu->backing_filename_offset = le32_to_cpu(le->backing_filename_offset);
+    cpu->backing_filename_size = le32_to_cpu(le->backing_filename_size);
+}
+
+static void qed_header_cpu_to_le(const QEDHeader *cpu, QEDHeader *le)
+{
+    le->magic = cpu_to_le32(cpu->magic);
+    le->cluster_size = cpu_to_le32(cpu->cluster_size);
+    le->table_size = cpu_to_le32(cpu->table_size);
+    le->header_size = cpu_to_le32(cpu->header_size);
+    le->features = cpu_to_le64(cpu->features);
+    le->compat_features = cpu_to_le64(cpu->compat_features);
+    le->autoclear_features = cpu_to_le64(cpu->autoclear_features);
+    le->l1_table_offset = cpu_to_le64(cpu->l1_table_offset);
+    le->image_size = cpu_to_le64(cpu->image_size);
+    le->backing_filename_offset = cpu_to_le32(cpu->backing_filename_offset);
+    le->backing_filename_size = cpu_to_le32(cpu->backing_filename_size);
+}
+
+int qed_write_header_sync(BDRVQEDState *s)
+{
+    QEDHeader le;
+    int ret;
+
+    qed_header_cpu_to_le(&s->header, &le);
+    ret = bdrv_pwrite(s->bs->file, 0, &le, sizeof(le));
+    if (ret != sizeof(le)) {
+        return ret;
+    }
+    return 0;
+}
+
+typedef struct {
+    GenericCB gencb;
+    BDRVQEDState *s;
+    struct iovec iov;
+    QEMUIOVector qiov;
+    int nsectors;
+    uint8_t *buf;
+} QEDWriteHeaderCB;
+
+static void qed_write_header_cb(void *opaque, int ret)
+{
+    QEDWriteHeaderCB *write_header_cb = opaque;
+
+    qemu_vfree(write_header_cb->buf);
+    gencb_complete(write_header_cb, ret);
+}
+
+static void qed_write_header_read_cb(void *opaque, int ret)
+{
+    QEDWriteHeaderCB *write_header_cb = opaque;
+    BDRVQEDState *s = write_header_cb->s;
+
+    if (ret) {
+        qed_write_header_cb(write_header_cb, ret);
+        return;
+    }
+
+    /* Update header */
+    qed_header_cpu_to_le(&s->header, (QEDHeader *)write_header_cb->buf);
+
+    bdrv_aio_writev(s->bs->file, 0, &write_header_cb->qiov,
+                    write_header_cb->nsectors, qed_write_header_cb,
+                    write_header_cb);
+}
+
+/**
+ * Update header in-place (does not rewrite backing filename or other strings)
+ *
+ * This function only updates known header fields in-place and does not affect
+ * extra data after the QED header.
+ */
+static void qed_write_header(BDRVQEDState *s, BlockDriverCompletionFunc cb,
+                             void *opaque)
+{
+    /* We must write full sectors for O_DIRECT but cannot necessarily generate
+     * the data following the header if an unrecognized compat feature is
+     * active.  Therefore, first read the sectors containing the header, update
+     * them, and write back.
+     */
+
+    int nsectors = (sizeof(QEDHeader) + BDRV_SECTOR_SIZE - 1) /
+                   BDRV_SECTOR_SIZE;
+    size_t len = nsectors * BDRV_SECTOR_SIZE;
+    QEDWriteHeaderCB *write_header_cb = gencb_alloc(sizeof(*write_header_cb),
+                                                    cb, opaque);
+
+    write_header_cb->s = s;
+    write_header_cb->nsectors = nsectors;
+    write_header_cb->buf = qemu_blockalign(s->bs, len);
+    write_header_cb->iov.iov_base = write_header_cb->buf;
+    write_header_cb->iov.iov_len = len;
+    qemu_iovec_init_external(&write_header_cb->qiov, &write_header_cb->iov, 1);
+
+    bdrv_aio_readv(s->bs->file, 0, &write_header_cb->qiov, nsectors,
+                   qed_write_header_read_cb, write_header_cb);
+}
+
+static uint64_t qed_max_image_size(uint32_t cluster_size, uint32_t table_size)
+{
+    uint64_t table_entries;
+    uint64_t l2_size;
+
+    table_entries = (table_size * cluster_size) / sizeof(uint64_t);
+    l2_size = table_entries * cluster_size;
+
+    return l2_size * table_entries;
+}
+
+static bool qed_is_cluster_size_valid(uint32_t cluster_size)
+{
+    if (cluster_size < QED_MIN_CLUSTER_SIZE ||
+        cluster_size > QED_MAX_CLUSTER_SIZE) {
+        return false;
+    }
+    if (cluster_size & (cluster_size - 1)) {
+        return false; /* not power of 2 */
+    }
+    return true;
+}
+
+static bool qed_is_table_size_valid(uint32_t table_size)
+{
+    if (table_size < QED_MIN_TABLE_SIZE ||
+        table_size > QED_MAX_TABLE_SIZE) {
+        return false;
+    }
+    if (table_size & (table_size - 1)) {
+        return false; /* not power of 2 */
+    }
+    return true;
+}
+
+static bool qed_is_image_size_valid(uint64_t image_size, uint32_t cluster_size,
+                                    uint32_t table_size)
+{
+    if (image_size % BDRV_SECTOR_SIZE != 0) {
+        return false; /* not multiple of sector size */
+    }
+    if (image_size > qed_max_image_size(cluster_size, table_size)) {
+        return false; /* image is too large */
+    }
+    return true;
+}
+
+/**
+ * Read a string of known length from the image file
+ *
+ * @file:       Image file
+ * @offset:     File offset to start of string, in bytes
+ * @n:          String length in bytes
+ * @buf:        Destination buffer
+ * @buflen:     Destination buffer length in bytes
+ * @ret:        0 on success, -errno on failure
+ *
+ * The string is NUL-terminated.
+ */
+static int qed_read_string(BlockDriverState *file, uint64_t offset, size_t n,
+                           char *buf, size_t buflen)
+{
+    int ret;
+    if (n >= buflen) {
+        return -EINVAL;
+    }
+    ret = bdrv_pread(file, offset, buf, n);
+    if (ret < 0) {
+        return ret;
+    }
+    buf[n] = '\0';
+    return 0;
+}
+
+/**
+ * Allocate new clusters
+ *
+ * @s:          QED state
+ * @n:          Number of contiguous clusters to allocate
+ * @ret:        Offset of first allocated cluster
+ *
+ * This function only produces the offset where the new clusters should be
+ * written.  It updates BDRVQEDState but does not make any changes to the image
+ * file.
+ */
+static uint64_t qed_alloc_clusters(BDRVQEDState *s, unsigned int n)
+{
+    uint64_t offset = s->file_size;
+    s->file_size += n * s->header.cluster_size;
+    return offset;
+}
+
+QEDTable *qed_alloc_table(BDRVQEDState *s)
+{
+    /* Honor O_DIRECT memory alignment requirements */
+    return qemu_blockalign(s->bs,
+                           s->header.cluster_size * s->header.table_size);
+}
+
+/**
+ * Allocate a new zeroed L2 table
+ */
+static CachedL2Table *qed_new_l2_table(BDRVQEDState *s)
+{
+    CachedL2Table *l2_table = qed_alloc_l2_cache_entry(&s->l2_cache);
+
+    l2_table->table = qed_alloc_table(s);
+    l2_table->offset = qed_alloc_clusters(s, s->header.table_size);
+
+    memset(l2_table->table->offsets, 0,
+           s->header.cluster_size * s->header.table_size);
+    return l2_table;
+}
+
+static void qed_aio_next_io(void *opaque, int ret);
+
+static void qed_plug_allocating_write_reqs(BDRVQEDState *s)
+{
+    assert(!s->allocating_write_reqs_plugged);
+
+    s->allocating_write_reqs_plugged = true;
+}
+
+static void qed_unplug_allocating_write_reqs(BDRVQEDState *s)
+{
+    QEDAIOCB *acb;
+
+    assert(s->allocating_write_reqs_plugged);
+
+    s->allocating_write_reqs_plugged = false;
+
+    acb = QSIMPLEQ_FIRST(&s->allocating_write_reqs);
+    if (acb) {
+        qed_aio_next_io(acb, 0);
+    }
+}
+
+static void qed_finish_clear_need_check(void *opaque, int ret)
+{
+    /* Do nothing */
+}
+
+static void qed_flush_after_clear_need_check(void *opaque, int ret)
+{
+    BDRVQEDState *s = opaque;
+
+    bdrv_aio_flush(s->bs, qed_finish_clear_need_check, s);
+
+    /* No need to wait until flush completes */
+    qed_unplug_allocating_write_reqs(s);
+}
+
+static void qed_clear_need_check(void *opaque, int ret)
+{
+    BDRVQEDState *s = opaque;
+
+    if (ret) {
+        qed_unplug_allocating_write_reqs(s);
+        return;
+    }
+
+    s->header.features &= ~QED_F_NEED_CHECK;
+    qed_write_header(s, qed_flush_after_clear_need_check, s);
+}
+
+static void qed_need_check_timer_cb(void *opaque)
+{
+    BDRVQEDState *s = opaque;
+
+    /* The timer should only fire when allocating writes have drained */
+    assert(!QSIMPLEQ_FIRST(&s->allocating_write_reqs));
+
+    trace_qed_need_check_timer_cb(s);
+
+    qed_plug_allocating_write_reqs(s);
+
+    /* Ensure writes are on disk before clearing flag */
+    bdrv_aio_flush(s->bs, qed_clear_need_check, s);
+}
+
+static void qed_start_need_check_timer(BDRVQEDState *s)
+{
+    trace_qed_start_need_check_timer(s);
+
+    /* Use vm_clock so we don't alter the image file while suspended for
+     * migration.
+     */
+    qemu_mod_timer(s->need_check_timer, qemu_get_clock_ns(vm_clock) +
+                   get_ticks_per_sec() * QED_NEED_CHECK_TIMEOUT);
+}
+
+/* It's okay to call this multiple times or when no timer is started */
+static void qed_cancel_need_check_timer(BDRVQEDState *s)
+{
+    trace_qed_cancel_need_check_timer(s);
+    qemu_del_timer(s->need_check_timer);
+}
+
+static void bdrv_qed_rebind(BlockDriverState *bs)
+{
+    BDRVQEDState *s = bs->opaque;
+    s->bs = bs;
+}
+
+static int bdrv_qed_open(BlockDriverState *bs, QDict *options, int flags)
+{
+    BDRVQEDState *s = bs->opaque;
+    QEDHeader le_header;
+    int64_t file_size;
+    int ret;
+
+    s->bs = bs;
+    QSIMPLEQ_INIT(&s->allocating_write_reqs);
+
+    ret = bdrv_pread(bs->file, 0, &le_header, sizeof(le_header));
+    if (ret < 0) {
+        return ret;
+    }
+    qed_header_le_to_cpu(&le_header, &s->header);
+
+    if (s->header.magic != QED_MAGIC) {
+        return -EMEDIUMTYPE;
+    }
+    if (s->header.features & ~QED_FEATURE_MASK) {
+        /* image uses unsupported feature bits */
+        char buf[64];
+        snprintf(buf, sizeof(buf), "%" PRIx64,
+            s->header.features & ~QED_FEATURE_MASK);
+        qerror_report(QERR_UNKNOWN_BLOCK_FORMAT_FEATURE,
+            bs->device_name, "QED", buf);
+        return -ENOTSUP;
+    }
+    if (!qed_is_cluster_size_valid(s->header.cluster_size)) {
+        return -EINVAL;
+    }
+
+    /* Round down file size to the last cluster */
+    file_size = bdrv_getlength(bs->file);
+    if (file_size < 0) {
+        return file_size;
+    }
+    s->file_size = qed_start_of_cluster(s, file_size);
+
+    if (!qed_is_table_size_valid(s->header.table_size)) {
+        return -EINVAL;
+    }
+    if (!qed_is_image_size_valid(s->header.image_size,
+                                 s->header.cluster_size,
+                                 s->header.table_size)) {
+        return -EINVAL;
+    }
+    if (!qed_check_table_offset(s, s->header.l1_table_offset)) {
+        return -EINVAL;
+    }
+
+    s->table_nelems = (s->header.cluster_size * s->header.table_size) /
+                      sizeof(uint64_t);
+    s->l2_shift = ffs(s->header.cluster_size) - 1;
+    s->l2_mask = s->table_nelems - 1;
+    s->l1_shift = s->l2_shift + ffs(s->table_nelems) - 1;
+
+    if ((s->header.features & QED_F_BACKING_FILE)) {
+        if ((uint64_t)s->header.backing_filename_offset +
+            s->header.backing_filename_size >
+            s->header.cluster_size * s->header.header_size) {
+            return -EINVAL;
+        }
+
+        ret = qed_read_string(bs->file, s->header.backing_filename_offset,
+                              s->header.backing_filename_size, bs->backing_file,
+                              sizeof(bs->backing_file));
+        if (ret < 0) {
+            return ret;
+        }
+
+        if (s->header.features & QED_F_BACKING_FORMAT_NO_PROBE) {
+            pstrcpy(bs->backing_format, sizeof(bs->backing_format), "raw");
+        }
+    }
+
+    /* Reset unknown autoclear feature bits.  This is a backwards
+     * compatibility mechanism that allows images to be opened by older
+     * programs, which "knock out" unknown feature bits.  When an image is
+     * opened by a newer program again it can detect that the autoclear
+     * feature is no longer valid.
+     */
+    if ((s->header.autoclear_features & ~QED_AUTOCLEAR_FEATURE_MASK) != 0 &&
+        !bdrv_is_read_only(bs->file) && !(flags & BDRV_O_INCOMING)) {
+        s->header.autoclear_features &= QED_AUTOCLEAR_FEATURE_MASK;
+
+        ret = qed_write_header_sync(s);
+        if (ret) {
+            return ret;
+        }
+
+        /* From here on only known autoclear feature bits are valid */
+        bdrv_flush(bs->file);
+    }
+
+    s->l1_table = qed_alloc_table(s);
+    qed_init_l2_cache(&s->l2_cache);
+
+    ret = qed_read_l1_table_sync(s);
+    if (ret) {
+        goto out;
+    }
+
+    /* If image was not closed cleanly, check consistency */
+    if (!(flags & BDRV_O_CHECK) && (s->header.features & QED_F_NEED_CHECK)) {
+        /* Read-only images cannot be fixed.  There is no risk of corruption
+         * since write operations are not possible.  Therefore, allow
+         * potentially inconsistent images to be opened read-only.  This can
+         * aid data recovery from an otherwise inconsistent image.
+         */
+        if (!bdrv_is_read_only(bs->file) &&
+            !(flags & BDRV_O_INCOMING)) {
+            BdrvCheckResult result = {0};
+
+            ret = qed_check(s, &result, true);
+            if (ret) {
+                goto out;
+            }
+        }
+    }
+
+    s->need_check_timer = qemu_new_timer_ns(vm_clock,
+                                            qed_need_check_timer_cb, s);
+
+out:
+    if (ret) {
+        qed_free_l2_cache(&s->l2_cache);
+        qemu_vfree(s->l1_table);
+    }
+    return ret;
+}
+
+/* We have nothing to do for QED reopen, stubs just return
+ * success */
+static int bdrv_qed_reopen_prepare(BDRVReopenState *state,
+                                   BlockReopenQueue *queue, Error **errp)
+{
+    return 0;
+}
+
+static void bdrv_qed_close(BlockDriverState *bs)
+{
+    BDRVQEDState *s = bs->opaque;
+
+    qed_cancel_need_check_timer(s);
+    qemu_free_timer(s->need_check_timer);
+
+    /* Ensure writes reach stable storage */
+    bdrv_flush(bs->file);
+
+    /* Clean shutdown, no check required on next open */
+    if (s->header.features & QED_F_NEED_CHECK) {
+        s->header.features &= ~QED_F_NEED_CHECK;
+        qed_write_header_sync(s);
+    }
+
+    qed_free_l2_cache(&s->l2_cache);
+    qemu_vfree(s->l1_table);
+}
+
+static int qed_create(const char *filename, uint32_t cluster_size,
+                      uint64_t image_size, uint32_t table_size,
+                      const char *backing_file, const char *backing_fmt)
+{
+    QEDHeader header = {
+        .magic = QED_MAGIC,
+        .cluster_size = cluster_size,
+        .table_size = table_size,
+        .header_size = 1,
+        .features = 0,
+        .compat_features = 0,
+        .l1_table_offset = cluster_size,
+        .image_size = image_size,
+    };
+    QEDHeader le_header;
+    uint8_t *l1_table = NULL;
+    size_t l1_size = header.cluster_size * header.table_size;
+    int ret = 0;
+    BlockDriverState *bs = NULL;
+
+    ret = bdrv_create_file(filename, NULL);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = bdrv_file_open(&bs, filename, NULL, BDRV_O_RDWR | BDRV_O_CACHE_WB);
+    if (ret < 0) {
+        return ret;
+    }
+
+    /* File must start empty and grow, check truncate is supported */
+    ret = bdrv_truncate(bs, 0);
+    if (ret < 0) {
+        goto out;
+    }
+
+    if (backing_file) {
+        header.features |= QED_F_BACKING_FILE;
+        header.backing_filename_offset = sizeof(le_header);
+        header.backing_filename_size = strlen(backing_file);
+
+        if (qed_fmt_is_raw(backing_fmt)) {
+            header.features |= QED_F_BACKING_FORMAT_NO_PROBE;
+        }
+    }
+
+    qed_header_cpu_to_le(&header, &le_header);
+    ret = bdrv_pwrite(bs, 0, &le_header, sizeof(le_header));
+    if (ret < 0) {
+        goto out;
+    }
+    ret = bdrv_pwrite(bs, sizeof(le_header), backing_file,
+                      header.backing_filename_size);
+    if (ret < 0) {
+        goto out;
+    }
+
+    l1_table = g_malloc0(l1_size);
+    ret = bdrv_pwrite(bs, header.l1_table_offset, l1_table, l1_size);
+    if (ret < 0) {
+        goto out;
+    }
+
+    ret = 0; /* success */
+out:
+    g_free(l1_table);
+    bdrv_delete(bs);
+    return ret;
+}
+
+static int bdrv_qed_create(const char *filename, QEMUOptionParameter *options)
+{
+    uint64_t image_size = 0;
+    uint32_t cluster_size = QED_DEFAULT_CLUSTER_SIZE;
+    uint32_t table_size = QED_DEFAULT_TABLE_SIZE;
+    const char *backing_file = NULL;
+    const char *backing_fmt = NULL;
+
+    while (options && options->name) {
+        if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+            image_size = options->value.n;
+        } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FILE)) {
+            backing_file = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_BACKING_FMT)) {
+            backing_fmt = options->value.s;
+        } else if (!strcmp(options->name, BLOCK_OPT_CLUSTER_SIZE)) {
+            if (options->value.n) {
+                cluster_size = options->value.n;
+            }
+        } else if (!strcmp(options->name, BLOCK_OPT_TABLE_SIZE)) {
+            if (options->value.n) {
+                table_size = options->value.n;
+            }
+        }
+        options++;
+    }
+
+    if (!qed_is_cluster_size_valid(cluster_size)) {
+        fprintf(stderr, "QED cluster size must be within range [%u, %u] and power of 2\n",
+                QED_MIN_CLUSTER_SIZE, QED_MAX_CLUSTER_SIZE);
+        return -EINVAL;
+    }
+    if (!qed_is_table_size_valid(table_size)) {
+        fprintf(stderr, "QED table size must be within range [%u, %u] and power of 2\n",
+                QED_MIN_TABLE_SIZE, QED_MAX_TABLE_SIZE);
+        return -EINVAL;
+    }
+    if (!qed_is_image_size_valid(image_size, cluster_size, table_size)) {
+        fprintf(stderr, "QED image size must be a non-zero multiple of "
+                        "cluster size and less than %" PRIu64 " bytes\n",
+                qed_max_image_size(cluster_size, table_size));
+        return -EINVAL;
+    }
+
+    return qed_create(filename, cluster_size, image_size, table_size,
+                      backing_file, backing_fmt);
+}
+
+typedef struct {
+    Coroutine *co;
+    int is_allocated;
+    int *pnum;
+} QEDIsAllocatedCB;
+
+static void qed_is_allocated_cb(void *opaque, int ret, uint64_t offset, size_t len)
+{
+    QEDIsAllocatedCB *cb = opaque;
+    *cb->pnum = len / BDRV_SECTOR_SIZE;
+    cb->is_allocated = (ret == QED_CLUSTER_FOUND || ret == QED_CLUSTER_ZERO);
+    if (cb->co) {
+        qemu_coroutine_enter(cb->co, NULL);
+    }
+}
+
+static int coroutine_fn bdrv_qed_co_is_allocated(BlockDriverState *bs,
+                                                 int64_t sector_num,
+                                                 int nb_sectors, int *pnum)
+{
+    BDRVQEDState *s = bs->opaque;
+    uint64_t pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE;
+    size_t len = (size_t)nb_sectors * BDRV_SECTOR_SIZE;
+    QEDIsAllocatedCB cb = {
+        .is_allocated = -1,
+        .pnum = pnum,
+    };
+    QEDRequest request = { .l2_table = NULL };
+
+    qed_find_cluster(s, &request, pos, len, qed_is_allocated_cb, &cb);
+
+    /* Now sleep if the callback wasn't invoked immediately */
+    while (cb.is_allocated == -1) {
+        cb.co = qemu_coroutine_self();
+        qemu_coroutine_yield();
+    }
+
+    qed_unref_l2_cache_entry(request.l2_table);
+
+    return cb.is_allocated;
+}
+
+static int bdrv_qed_make_empty(BlockDriverState *bs)
+{
+    return -ENOTSUP;
+}
+
+static BDRVQEDState *acb_to_s(QEDAIOCB *acb)
+{
+    return acb->common.bs->opaque;
+}
+
+/**
+ * Read from the backing file or zero-fill if no backing file
+ *
+ * @s:          QED state
+ * @pos:        Byte position in device
+ * @qiov:       Destination I/O vector
+ * @cb:         Completion function
+ * @opaque:     User data for completion function
+ *
+ * This function reads qiov->size bytes starting at pos from the backing file.
+ * If there is no backing file then zeroes are read.
+ */
+static void qed_read_backing_file(BDRVQEDState *s, uint64_t pos,
+                                  QEMUIOVector *qiov,
+                                  BlockDriverCompletionFunc *cb, void *opaque)
+{
+    uint64_t backing_length = 0;
+    size_t size;
+
+    /* If there is a backing file, get its length.  Treat the absence of a
+     * backing file like a zero length backing file.
+     */
+    if (s->bs->backing_hd) {
+        int64_t l = bdrv_getlength(s->bs->backing_hd);
+        if (l < 0) {
+            cb(opaque, l);
+            return;
+        }
+        backing_length = l;
+    }
+
+    /* Zero all sectors if reading beyond the end of the backing file */
+    if (pos >= backing_length ||
+        pos + qiov->size > backing_length) {
+        qemu_iovec_memset(qiov, 0, 0, qiov->size);
+    }
+
+    /* Complete now if there are no backing file sectors to read */
+    if (pos >= backing_length) {
+        cb(opaque, 0);
+        return;
+    }
+
+    /* If the read straddles the end of the backing file, shorten it */
+    size = MIN((uint64_t)backing_length - pos, qiov->size);
+
+    BLKDBG_EVENT(s->bs->file, BLKDBG_READ_BACKING_AIO);
+    bdrv_aio_readv(s->bs->backing_hd, pos / BDRV_SECTOR_SIZE,
+                   qiov, size / BDRV_SECTOR_SIZE, cb, opaque);
+}
+
+typedef struct {
+    GenericCB gencb;
+    BDRVQEDState *s;
+    QEMUIOVector qiov;
+    struct iovec iov;
+    uint64_t offset;
+} CopyFromBackingFileCB;
+
+static void qed_copy_from_backing_file_cb(void *opaque, int ret)
+{
+    CopyFromBackingFileCB *copy_cb = opaque;
+    qemu_vfree(copy_cb->iov.iov_base);
+    gencb_complete(&copy_cb->gencb, ret);
+}
+
+static void qed_copy_from_backing_file_write(void *opaque, int ret)
+{
+    CopyFromBackingFileCB *copy_cb = opaque;
+    BDRVQEDState *s = copy_cb->s;
+
+    if (ret) {
+        qed_copy_from_backing_file_cb(copy_cb, ret);
+        return;
+    }
+
+    BLKDBG_EVENT(s->bs->file, BLKDBG_COW_WRITE);
+    bdrv_aio_writev(s->bs->file, copy_cb->offset / BDRV_SECTOR_SIZE,
+                    &copy_cb->qiov, copy_cb->qiov.size / BDRV_SECTOR_SIZE,
+                    qed_copy_from_backing_file_cb, copy_cb);
+}
+
+/**
+ * Copy data from backing file into the image
+ *
+ * @s:          QED state
+ * @pos:        Byte position in device
+ * @len:        Number of bytes
+ * @offset:     Byte offset in image file
+ * @cb:         Completion function
+ * @opaque:     User data for completion function
+ */
+static void qed_copy_from_backing_file(BDRVQEDState *s, uint64_t pos,
+                                       uint64_t len, uint64_t offset,
+                                       BlockDriverCompletionFunc *cb,
+                                       void *opaque)
+{
+    CopyFromBackingFileCB *copy_cb;
+
+    /* Skip copy entirely if there is no work to do */
+    if (len == 0) {
+        cb(opaque, 0);
+        return;
+    }
+
+    copy_cb = gencb_alloc(sizeof(*copy_cb), cb, opaque);
+    copy_cb->s = s;
+    copy_cb->offset = offset;
+    copy_cb->iov.iov_base = qemu_blockalign(s->bs, len);
+    copy_cb->iov.iov_len = len;
+    qemu_iovec_init_external(&copy_cb->qiov, &copy_cb->iov, 1);
+
+    qed_read_backing_file(s, pos, &copy_cb->qiov,
+                          qed_copy_from_backing_file_write, copy_cb);
+}
+
+/**
+ * Link one or more contiguous clusters into a table
+ *
+ * @s:              QED state
+ * @table:          L2 table
+ * @index:          First cluster index
+ * @n:              Number of contiguous clusters
+ * @cluster:        First cluster offset
+ *
+ * The cluster offset may be an allocated byte offset in the image file, the
+ * zero cluster marker, or the unallocated cluster marker.
+ */
+static void qed_update_l2_table(BDRVQEDState *s, QEDTable *table, int index,
+                                unsigned int n, uint64_t cluster)
+{
+    int i;
+    for (i = index; i < index + n; i++) {
+        table->offsets[i] = cluster;
+        if (!qed_offset_is_unalloc_cluster(cluster) &&
+            !qed_offset_is_zero_cluster(cluster)) {
+            cluster += s->header.cluster_size;
+        }
+    }
+}
+
+static void qed_aio_complete_bh(void *opaque)
+{
+    QEDAIOCB *acb = opaque;
+    BlockDriverCompletionFunc *cb = acb->common.cb;
+    void *user_opaque = acb->common.opaque;
+    int ret = acb->bh_ret;
+    bool *finished = acb->finished;
+
+    qemu_bh_delete(acb->bh);
+    qemu_aio_release(acb);
+
+    /* Invoke callback */
+    cb(user_opaque, ret);
+
+    /* Signal cancel completion */
+    if (finished) {
+        *finished = true;
+    }
+}
+
+static void qed_aio_complete(QEDAIOCB *acb, int ret)
+{
+    BDRVQEDState *s = acb_to_s(acb);
+
+    trace_qed_aio_complete(s, acb, ret);
+
+    /* Free resources */
+    qemu_iovec_destroy(&acb->cur_qiov);
+    qed_unref_l2_cache_entry(acb->request.l2_table);
+
+    /* Free the buffer we may have allocated for zero writes */
+    if (acb->flags & QED_AIOCB_ZERO) {
+        qemu_vfree(acb->qiov->iov[0].iov_base);
+        acb->qiov->iov[0].iov_base = NULL;
+    }
+
+    /* Arrange for a bh to invoke the completion function */
+    acb->bh_ret = ret;
+    acb->bh = qemu_bh_new(qed_aio_complete_bh, acb);
+    qemu_bh_schedule(acb->bh);
+
+    /* Start next allocating write request waiting behind this one.  Note that
+     * requests enqueue themselves when they first hit an unallocated cluster
+     * but they wait until the entire request is finished before waking up the
+     * next request in the queue.  This ensures that we don't cycle through
+     * requests multiple times but rather finish one at a time completely.
+     */
+    if (acb == QSIMPLEQ_FIRST(&s->allocating_write_reqs)) {
+        QSIMPLEQ_REMOVE_HEAD(&s->allocating_write_reqs, next);
+        acb = QSIMPLEQ_FIRST(&s->allocating_write_reqs);
+        if (acb) {
+            qed_aio_next_io(acb, 0);
+        } else if (s->header.features & QED_F_NEED_CHECK) {
+            qed_start_need_check_timer(s);
+        }
+    }
+}
+
+/**
+ * Commit the current L2 table to the cache
+ */
+static void qed_commit_l2_update(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    CachedL2Table *l2_table = acb->request.l2_table;
+    uint64_t l2_offset = l2_table->offset;
+
+    qed_commit_l2_cache_entry(&s->l2_cache, l2_table);
+
+    /* This is guaranteed to succeed because we just committed the entry to the
+     * cache.
+     */
+    acb->request.l2_table = qed_find_l2_cache_entry(&s->l2_cache, l2_offset);
+    assert(acb->request.l2_table != NULL);
+
+    qed_aio_next_io(opaque, ret);
+}
+
+/**
+ * Update L1 table with new L2 table offset and write it out
+ */
+static void qed_aio_write_l1_update(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    int index;
+
+    if (ret) {
+        qed_aio_complete(acb, ret);
+        return;
+    }
+
+    index = qed_l1_index(s, acb->cur_pos);
+    s->l1_table->offsets[index] = acb->request.l2_table->offset;
+
+    qed_write_l1_table(s, index, 1, qed_commit_l2_update, acb);
+}
+
+/**
+ * Update L2 table with new cluster offsets and write them out
+ */
+static void qed_aio_write_l2_update(QEDAIOCB *acb, int ret, uint64_t offset)
+{
+    BDRVQEDState *s = acb_to_s(acb);
+    bool need_alloc = acb->find_cluster_ret == QED_CLUSTER_L1;
+    int index;
+
+    if (ret) {
+        goto err;
+    }
+
+    if (need_alloc) {
+        qed_unref_l2_cache_entry(acb->request.l2_table);
+        acb->request.l2_table = qed_new_l2_table(s);
+    }
+
+    index = qed_l2_index(s, acb->cur_pos);
+    qed_update_l2_table(s, acb->request.l2_table->table, index, acb->cur_nclusters,
+                         offset);
+
+    if (need_alloc) {
+        /* Write out the whole new L2 table */
+        qed_write_l2_table(s, &acb->request, 0, s->table_nelems, true,
+                            qed_aio_write_l1_update, acb);
+    } else {
+        /* Write out only the updated part of the L2 table */
+        qed_write_l2_table(s, &acb->request, index, acb->cur_nclusters, false,
+                            qed_aio_next_io, acb);
+    }
+    return;
+
+err:
+    qed_aio_complete(acb, ret);
+}
+
+static void qed_aio_write_l2_update_cb(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    qed_aio_write_l2_update(acb, ret, acb->cur_cluster);
+}
+
+/**
+ * Flush new data clusters before updating the L2 table
+ *
+ * This flush is necessary when a backing file is in use.  A crash during an
+ * allocating write could result in empty clusters in the image.  If the write
+ * only touched a subregion of the cluster, then backing image sectors have
+ * been lost in the untouched region.  The solution is to flush after writing a
+ * new data cluster and before updating the L2 table.
+ */
+static void qed_aio_write_flush_before_l2_update(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+
+    if (!bdrv_aio_flush(s->bs->file, qed_aio_write_l2_update_cb, opaque)) {
+        qed_aio_complete(acb, -EIO);
+    }
+}
+
+/**
+ * Write data to the image file
+ */
+static void qed_aio_write_main(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    uint64_t offset = acb->cur_cluster +
+                      qed_offset_into_cluster(s, acb->cur_pos);
+    BlockDriverCompletionFunc *next_fn;
+
+    trace_qed_aio_write_main(s, acb, ret, offset, acb->cur_qiov.size);
+
+    if (ret) {
+        qed_aio_complete(acb, ret);
+        return;
+    }
+
+    if (acb->find_cluster_ret == QED_CLUSTER_FOUND) {
+        next_fn = qed_aio_next_io;
+    } else {
+        if (s->bs->backing_hd) {
+            next_fn = qed_aio_write_flush_before_l2_update;
+        } else {
+            next_fn = qed_aio_write_l2_update_cb;
+        }
+    }
+
+    BLKDBG_EVENT(s->bs->file, BLKDBG_WRITE_AIO);
+    bdrv_aio_writev(s->bs->file, offset / BDRV_SECTOR_SIZE,
+                    &acb->cur_qiov, acb->cur_qiov.size / BDRV_SECTOR_SIZE,
+                    next_fn, acb);
+}
+
+/**
+ * Populate back untouched region of new data cluster
+ */
+static void qed_aio_write_postfill(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    uint64_t start = acb->cur_pos + acb->cur_qiov.size;
+    uint64_t len =
+        qed_start_of_cluster(s, start + s->header.cluster_size - 1) - start;
+    uint64_t offset = acb->cur_cluster +
+                      qed_offset_into_cluster(s, acb->cur_pos) +
+                      acb->cur_qiov.size;
+
+    if (ret) {
+        qed_aio_complete(acb, ret);
+        return;
+    }
+
+    trace_qed_aio_write_postfill(s, acb, start, len, offset);
+    qed_copy_from_backing_file(s, start, len, offset,
+                                qed_aio_write_main, acb);
+}
+
+/**
+ * Populate front untouched region of new data cluster
+ */
+static void qed_aio_write_prefill(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    uint64_t start = qed_start_of_cluster(s, acb->cur_pos);
+    uint64_t len = qed_offset_into_cluster(s, acb->cur_pos);
+
+    trace_qed_aio_write_prefill(s, acb, start, len, acb->cur_cluster);
+    qed_copy_from_backing_file(s, start, len, acb->cur_cluster,
+                                qed_aio_write_postfill, acb);
+}
+
+/**
+ * Check if the QED_F_NEED_CHECK bit should be set during allocating write
+ */
+static bool qed_should_set_need_check(BDRVQEDState *s)
+{
+    /* The flush before L2 update path ensures consistency */
+    if (s->bs->backing_hd) {
+        return false;
+    }
+
+    return !(s->header.features & QED_F_NEED_CHECK);
+}
+
+static void qed_aio_write_zero_cluster(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+
+    if (ret) {
+        qed_aio_complete(acb, ret);
+        return;
+    }
+
+    qed_aio_write_l2_update(acb, 0, 1);
+}
+
+/**
+ * Write new data cluster
+ *
+ * @acb:        Write request
+ * @len:        Length in bytes
+ *
+ * This path is taken when writing to previously unallocated clusters.
+ */
+static void qed_aio_write_alloc(QEDAIOCB *acb, size_t len)
+{
+    BDRVQEDState *s = acb_to_s(acb);
+    BlockDriverCompletionFunc *cb;
+
+    /* Cancel timer when the first allocating request comes in */
+    if (QSIMPLEQ_EMPTY(&s->allocating_write_reqs)) {
+        qed_cancel_need_check_timer(s);
+    }
+
+    /* Freeze this request if another allocating write is in progress */
+    if (acb != QSIMPLEQ_FIRST(&s->allocating_write_reqs)) {
+        QSIMPLEQ_INSERT_TAIL(&s->allocating_write_reqs, acb, next);
+    }
+    if (acb != QSIMPLEQ_FIRST(&s->allocating_write_reqs) ||
+        s->allocating_write_reqs_plugged) {
+        return; /* wait for existing request to finish */
+    }
+
+    acb->cur_nclusters = qed_bytes_to_clusters(s,
+            qed_offset_into_cluster(s, acb->cur_pos) + len);
+    qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+
+    if (acb->flags & QED_AIOCB_ZERO) {
+        /* Skip ahead if the clusters are already zero */
+        if (acb->find_cluster_ret == QED_CLUSTER_ZERO) {
+            qed_aio_next_io(acb, 0);
+            return;
+        }
+
+        cb = qed_aio_write_zero_cluster;
+    } else {
+        cb = qed_aio_write_prefill;
+        acb->cur_cluster = qed_alloc_clusters(s, acb->cur_nclusters);
+    }
+
+    if (qed_should_set_need_check(s)) {
+        s->header.features |= QED_F_NEED_CHECK;
+        qed_write_header(s, cb, acb);
+    } else {
+        cb(acb, 0);
+    }
+}
+
+/**
+ * Write data cluster in place
+ *
+ * @acb:        Write request
+ * @offset:     Cluster offset in bytes
+ * @len:        Length in bytes
+ *
+ * This path is taken when writing to already allocated clusters.
+ */
+static void qed_aio_write_inplace(QEDAIOCB *acb, uint64_t offset, size_t len)
+{
+    /* Allocate buffer for zero writes */
+    if (acb->flags & QED_AIOCB_ZERO) {
+        struct iovec *iov = acb->qiov->iov;
+
+        if (!iov->iov_base) {
+            iov->iov_base = qemu_blockalign(acb->common.bs, iov->iov_len);
+            memset(iov->iov_base, 0, iov->iov_len);
+        }
+    }
+
+    /* Calculate the I/O vector */
+    acb->cur_cluster = offset;
+    qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+
+    /* Do the actual write */
+    qed_aio_write_main(acb, 0);
+}
+
+/**
+ * Write data cluster
+ *
+ * @opaque:     Write request
+ * @ret:        QED_CLUSTER_FOUND, QED_CLUSTER_L2, QED_CLUSTER_L1,
+ *              or -errno
+ * @offset:     Cluster offset in bytes
+ * @len:        Length in bytes
+ *
+ * Callback from qed_find_cluster().
+ */
+static void qed_aio_write_data(void *opaque, int ret,
+                               uint64_t offset, size_t len)
+{
+    QEDAIOCB *acb = opaque;
+
+    trace_qed_aio_write_data(acb_to_s(acb), acb, ret, offset, len);
+
+    acb->find_cluster_ret = ret;
+
+    switch (ret) {
+    case QED_CLUSTER_FOUND:
+        qed_aio_write_inplace(acb, offset, len);
+        break;
+
+    case QED_CLUSTER_L2:
+    case QED_CLUSTER_L1:
+    case QED_CLUSTER_ZERO:
+        qed_aio_write_alloc(acb, len);
+        break;
+
+    default:
+        qed_aio_complete(acb, ret);
+        break;
+    }
+}
+
+/**
+ * Read data cluster
+ *
+ * @opaque:     Read request
+ * @ret:        QED_CLUSTER_FOUND, QED_CLUSTER_L2, QED_CLUSTER_L1,
+ *              or -errno
+ * @offset:     Cluster offset in bytes
+ * @len:        Length in bytes
+ *
+ * Callback from qed_find_cluster().
+ */
+static void qed_aio_read_data(void *opaque, int ret,
+                              uint64_t offset, size_t len)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    BlockDriverState *bs = acb->common.bs;
+
+    /* Adjust offset into cluster */
+    offset += qed_offset_into_cluster(s, acb->cur_pos);
+
+    trace_qed_aio_read_data(s, acb, ret, offset, len);
+
+    if (ret < 0) {
+        goto err;
+    }
+
+    qemu_iovec_concat(&acb->cur_qiov, acb->qiov, acb->qiov_offset, len);
+
+    /* Handle zero cluster and backing file reads */
+    if (ret == QED_CLUSTER_ZERO) {
+        qemu_iovec_memset(&acb->cur_qiov, 0, 0, acb->cur_qiov.size);
+        qed_aio_next_io(acb, 0);
+        return;
+    } else if (ret != QED_CLUSTER_FOUND) {
+        qed_read_backing_file(s, acb->cur_pos, &acb->cur_qiov,
+                              qed_aio_next_io, acb);
+        return;
+    }
+
+    BLKDBG_EVENT(bs->file, BLKDBG_READ_AIO);
+    bdrv_aio_readv(bs->file, offset / BDRV_SECTOR_SIZE,
+                   &acb->cur_qiov, acb->cur_qiov.size / BDRV_SECTOR_SIZE,
+                   qed_aio_next_io, acb);
+    return;
+
+err:
+    qed_aio_complete(acb, ret);
+}
+
+/**
+ * Begin next I/O or complete the request
+ */
+static void qed_aio_next_io(void *opaque, int ret)
+{
+    QEDAIOCB *acb = opaque;
+    BDRVQEDState *s = acb_to_s(acb);
+    QEDFindClusterFunc *io_fn = (acb->flags & QED_AIOCB_WRITE) ?
+                                qed_aio_write_data : qed_aio_read_data;
+
+    trace_qed_aio_next_io(s, acb, ret, acb->cur_pos + acb->cur_qiov.size);
+
+    /* Handle I/O error */
+    if (ret) {
+        qed_aio_complete(acb, ret);
+        return;
+    }
+
+    acb->qiov_offset += acb->cur_qiov.size;
+    acb->cur_pos += acb->cur_qiov.size;
+    qemu_iovec_reset(&acb->cur_qiov);
+
+    /* Complete request */
+    if (acb->cur_pos >= acb->end_pos) {
+        qed_aio_complete(acb, 0);
+        return;
+    }
+
+    /* Find next cluster and start I/O */
+    qed_find_cluster(s, &acb->request,
+                      acb->cur_pos, acb->end_pos - acb->cur_pos,
+                      io_fn, acb);
+}
+
+static BlockDriverAIOCB *qed_aio_setup(BlockDriverState *bs,
+                                       int64_t sector_num,
+                                       QEMUIOVector *qiov, int nb_sectors,
+                                       BlockDriverCompletionFunc *cb,
+                                       void *opaque, int flags)
+{
+    QEDAIOCB *acb = qemu_aio_get(&qed_aiocb_info, bs, cb, opaque);
+
+    trace_qed_aio_setup(bs->opaque, acb, sector_num, nb_sectors,
+                        opaque, flags);
+
+    acb->flags = flags;
+    acb->finished = NULL;
+    acb->qiov = qiov;
+    acb->qiov_offset = 0;
+    acb->cur_pos = (uint64_t)sector_num * BDRV_SECTOR_SIZE;
+    acb->end_pos = acb->cur_pos + nb_sectors * BDRV_SECTOR_SIZE;
+    acb->request.l2_table = NULL;
+    qemu_iovec_init(&acb->cur_qiov, qiov->niov);
+
+    /* Start request */
+    qed_aio_next_io(acb, 0);
+    return &acb->common;
+}
+
+static BlockDriverAIOCB *bdrv_qed_aio_readv(BlockDriverState *bs,
+                                            int64_t sector_num,
+                                            QEMUIOVector *qiov, int nb_sectors,
+                                            BlockDriverCompletionFunc *cb,
+                                            void *opaque)
+{
+    return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
+}
+
+static BlockDriverAIOCB *bdrv_qed_aio_writev(BlockDriverState *bs,
+                                             int64_t sector_num,
+                                             QEMUIOVector *qiov, int nb_sectors,
+                                             BlockDriverCompletionFunc *cb,
+                                             void *opaque)
+{
+    return qed_aio_setup(bs, sector_num, qiov, nb_sectors, cb,
+                         opaque, QED_AIOCB_WRITE);
+}
+
+typedef struct {
+    Coroutine *co;
+    int ret;
+    bool done;
+} QEDWriteZeroesCB;
+
+static void coroutine_fn qed_co_write_zeroes_cb(void *opaque, int ret)
+{
+    QEDWriteZeroesCB *cb = opaque;
+
+    cb->done = true;
+    cb->ret = ret;
+    if (cb->co) {
+        qemu_coroutine_enter(cb->co, NULL);
+    }
+}
+
+static int coroutine_fn bdrv_qed_co_write_zeroes(BlockDriverState *bs,
+                                                 int64_t sector_num,
+                                                 int nb_sectors)
+{
+    BlockDriverAIOCB *blockacb;
+    BDRVQEDState *s = bs->opaque;
+    QEDWriteZeroesCB cb = { .done = false };
+    QEMUIOVector qiov;
+    struct iovec iov;
+
+    /* Refuse if there are untouched backing file sectors */
+    if (bs->backing_hd) {
+        if (qed_offset_into_cluster(s, sector_num * BDRV_SECTOR_SIZE) != 0) {
+            return -ENOTSUP;
+        }
+        if (qed_offset_into_cluster(s, nb_sectors * BDRV_SECTOR_SIZE) != 0) {
+            return -ENOTSUP;
+        }
+    }
+
+    /* Zero writes start without an I/O buffer.  If a buffer becomes necessary
+     * then it will be allocated during request processing.
+     */
+    iov.iov_base = NULL,
+    iov.iov_len  = nb_sectors * BDRV_SECTOR_SIZE,
+
+    qemu_iovec_init_external(&qiov, &iov, 1);
+    blockacb = qed_aio_setup(bs, sector_num, &qiov, nb_sectors,
+                             qed_co_write_zeroes_cb, &cb,
+                             QED_AIOCB_WRITE | QED_AIOCB_ZERO);
+    if (!blockacb) {
+        return -EIO;
+    }
+    if (!cb.done) {
+        cb.co = qemu_coroutine_self();
+        qemu_coroutine_yield();
+    }
+    assert(cb.done);
+    return cb.ret;
+}
+
+static int bdrv_qed_truncate(BlockDriverState *bs, int64_t offset)
+{
+    BDRVQEDState *s = bs->opaque;
+    uint64_t old_image_size;
+    int ret;
+
+    if (!qed_is_image_size_valid(offset, s->header.cluster_size,
+                                 s->header.table_size)) {
+        return -EINVAL;
+    }
+
+    /* Shrinking is currently not supported */
+    if ((uint64_t)offset < s->header.image_size) {
+        return -ENOTSUP;
+    }
+
+    old_image_size = s->header.image_size;
+    s->header.image_size = offset;
+    ret = qed_write_header_sync(s);
+    if (ret < 0) {
+        s->header.image_size = old_image_size;
+    }
+    return ret;
+}
+
+static int64_t bdrv_qed_getlength(BlockDriverState *bs)
+{
+    BDRVQEDState *s = bs->opaque;
+    return s->header.image_size;
+}
+
+static int bdrv_qed_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
+{
+    BDRVQEDState *s = bs->opaque;
+
+    memset(bdi, 0, sizeof(*bdi));
+    bdi->cluster_size = s->header.cluster_size;
+    bdi->is_dirty = s->header.features & QED_F_NEED_CHECK;
+    return 0;
+}
+
+static int bdrv_qed_change_backing_file(BlockDriverState *bs,
+                                        const char *backing_file,
+                                        const char *backing_fmt)
+{
+    BDRVQEDState *s = bs->opaque;
+    QEDHeader new_header, le_header;
+    void *buffer;
+    size_t buffer_len, backing_file_len;
+    int ret;
+
+    /* Refuse to set backing filename if unknown compat feature bits are
+     * active.  If the image uses an unknown compat feature then we may not
+     * know the layout of data following the header structure and cannot safely
+     * add a new string.
+     */
+    if (backing_file && (s->header.compat_features &
+                         ~QED_COMPAT_FEATURE_MASK)) {
+        return -ENOTSUP;
+    }
+
+    memcpy(&new_header, &s->header, sizeof(new_header));
+
+    new_header.features &= ~(QED_F_BACKING_FILE |
+                             QED_F_BACKING_FORMAT_NO_PROBE);
+
+    /* Adjust feature flags */
+    if (backing_file) {
+        new_header.features |= QED_F_BACKING_FILE;
+
+        if (qed_fmt_is_raw(backing_fmt)) {
+            new_header.features |= QED_F_BACKING_FORMAT_NO_PROBE;
+        }
+    }
+
+    /* Calculate new header size */
+    backing_file_len = 0;
+
+    if (backing_file) {
+        backing_file_len = strlen(backing_file);
+    }
+
+    buffer_len = sizeof(new_header);
+    new_header.backing_filename_offset = buffer_len;
+    new_header.backing_filename_size = backing_file_len;
+    buffer_len += backing_file_len;
+
+    /* Make sure we can rewrite header without failing */
+    if (buffer_len > new_header.header_size * new_header.cluster_size) {
+        return -ENOSPC;
+    }
+
+    /* Prepare new header */
+    buffer = g_malloc(buffer_len);
+
+    qed_header_cpu_to_le(&new_header, &le_header);
+    memcpy(buffer, &le_header, sizeof(le_header));
+    buffer_len = sizeof(le_header);
+
+    if (backing_file) {
+        memcpy(buffer + buffer_len, backing_file, backing_file_len);
+        buffer_len += backing_file_len;
+    }
+
+    /* Write new header */
+    ret = bdrv_pwrite_sync(bs->file, 0, buffer, buffer_len);
+    g_free(buffer);
+    if (ret == 0) {
+        memcpy(&s->header, &new_header, sizeof(new_header));
+    }
+    return ret;
+}
+
+static void bdrv_qed_invalidate_cache(BlockDriverState *bs)
+{
+    BDRVQEDState *s = bs->opaque;
+
+    bdrv_qed_close(bs);
+    memset(s, 0, sizeof(BDRVQEDState));
+    bdrv_qed_open(bs, NULL, bs->open_flags);
+}
+
+static int bdrv_qed_check(BlockDriverState *bs, BdrvCheckResult *result,
+                          BdrvCheckMode fix)
+{
+    BDRVQEDState *s = bs->opaque;
+
+    return qed_check(s, result, !!fix);
+}
+
+static QEMUOptionParameter qed_create_options[] = {
+    {
+        .name = BLOCK_OPT_SIZE,
+        .type = OPT_SIZE,
+        .help = "Virtual disk size (in bytes)"
+    }, {
+        .name = BLOCK_OPT_BACKING_FILE,
+        .type = OPT_STRING,
+        .help = "File name of a base image"
+    }, {
+        .name = BLOCK_OPT_BACKING_FMT,
+        .type = OPT_STRING,
+        .help = "Image format of the base image"
+    }, {
+        .name = BLOCK_OPT_CLUSTER_SIZE,
+        .type = OPT_SIZE,
+        .help = "Cluster size (in bytes)",
+        .value = { .n = QED_DEFAULT_CLUSTER_SIZE },
+    }, {
+        .name = BLOCK_OPT_TABLE_SIZE,
+        .type = OPT_SIZE,
+        .help = "L1/L2 table size (in clusters)"
+    },
+    { /* end of list */ }
+};
+
+static BlockDriver bdrv_qed = {
+    .format_name              = "qed",
+    .instance_size            = sizeof(BDRVQEDState),
+    .create_options           = qed_create_options,
+
+    .bdrv_probe               = bdrv_qed_probe,
+    .bdrv_rebind              = bdrv_qed_rebind,
+    .bdrv_open                = bdrv_qed_open,
+    .bdrv_close               = bdrv_qed_close,
+    .bdrv_reopen_prepare      = bdrv_qed_reopen_prepare,
+    .bdrv_create              = bdrv_qed_create,
+    .bdrv_has_zero_init       = bdrv_has_zero_init_1,
+    .bdrv_co_is_allocated     = bdrv_qed_co_is_allocated,
+    .bdrv_make_empty          = bdrv_qed_make_empty,
+    .bdrv_aio_readv           = bdrv_qed_aio_readv,
+    .bdrv_aio_writev          = bdrv_qed_aio_writev,
+    .bdrv_co_write_zeroes     = bdrv_qed_co_write_zeroes,
+    .bdrv_truncate            = bdrv_qed_truncate,
+    .bdrv_getlength           = bdrv_qed_getlength,
+    .bdrv_get_info            = bdrv_qed_get_info,
+    .bdrv_change_backing_file = bdrv_qed_change_backing_file,
+    .bdrv_invalidate_cache    = bdrv_qed_invalidate_cache,
+    .bdrv_check               = bdrv_qed_check,
+};
+
+static void bdrv_qed_init(void)
+{
+    bdrv_register(&bdrv_qed);
+}
+
+block_init(bdrv_qed_init);
diff --git a/contrib/qemu/block/qed.h b/contrib/qemu/block/qed.h
new file mode 100644
index 000000000..2b4ddedf3
--- /dev/null
+++ b/contrib/qemu/block/qed.h
@@ -0,0 +1,344 @@
+/*
+ * QEMU Enhanced Disk Format
+ *
+ * Copyright IBM, Corp. 2010
+ *
+ * Authors:
+ *  Stefan Hajnoczi   <stefanha@linux.vnet.ibm.com>
+ *  Anthony Liguori   <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ *
+ */
+
+#ifndef BLOCK_QED_H
+#define BLOCK_QED_H
+
+#include "block/block_int.h"
+
+/* The layout of a QED file is as follows:
+ *
+ * +--------+----------+----------+----------+-----+
+ * | header | L1 table | cluster0 | cluster1 | ... |
+ * +--------+----------+----------+----------+-----+
+ *
+ * There is a 2-level pagetable for cluster allocation:
+ *
+ *                     +----------+
+ *                     | L1 table |
+ *                     +----------+
+ *                ,------'  |  '------.
+ *           +----------+   |    +----------+
+ *           | L2 table |  ...   | L2 table |
+ *           +----------+        +----------+
+ *       ,------'  |  '------.
+ *  +----------+   |    +----------+
+ *  |   Data   |  ...   |   Data   |
+ *  +----------+        +----------+
+ *
+ * The L1 table is fixed size and always present.  L2 tables are allocated on
+ * demand.  The L1 table size determines the maximum possible image size; it
+ * can be influenced using the cluster_size and table_size values.
+ *
+ * All fields are little-endian on disk.
+ */
+
+enum {
+    QED_MAGIC = 'Q' | 'E' << 8 | 'D' << 16 | '\0' << 24,
+
+    /* The image supports a backing file */
+    QED_F_BACKING_FILE = 0x01,
+
+    /* The image needs a consistency check before use */
+    QED_F_NEED_CHECK = 0x02,
+
+    /* The backing file format must not be probed, treat as raw image */
+    QED_F_BACKING_FORMAT_NO_PROBE = 0x04,
+
+    /* Feature bits must be used when the on-disk format changes */
+    QED_FEATURE_MASK = QED_F_BACKING_FILE | /* supported feature bits */
+                       QED_F_NEED_CHECK |
+                       QED_F_BACKING_FORMAT_NO_PROBE,
+    QED_COMPAT_FEATURE_MASK = 0,            /* supported compat feature bits */
+    QED_AUTOCLEAR_FEATURE_MASK = 0,         /* supported autoclear feature bits */
+
+    /* Data is stored in groups of sectors called clusters.  Cluster size must
+     * be large to avoid keeping too much metadata.  I/O requests that have
+     * sub-cluster size will require read-modify-write.
+     */
+    QED_MIN_CLUSTER_SIZE = 4 * 1024, /* in bytes */
+    QED_MAX_CLUSTER_SIZE = 64 * 1024 * 1024,
+    QED_DEFAULT_CLUSTER_SIZE = 64 * 1024,
+
+    /* Allocated clusters are tracked using a 2-level pagetable.  Table size is
+     * a multiple of clusters so large maximum image sizes can be supported
+     * without jacking up the cluster size too much.
+     */
+    QED_MIN_TABLE_SIZE = 1,        /* in clusters */
+    QED_MAX_TABLE_SIZE = 16,
+    QED_DEFAULT_TABLE_SIZE = 4,
+
+    /* Delay to flush and clean image after last allocating write completes */
+    QED_NEED_CHECK_TIMEOUT = 5,    /* in seconds */
+};
+
+typedef struct {
+    uint32_t magic;                 /* QED\0 */
+
+    uint32_t cluster_size;          /* in bytes */
+    uint32_t table_size;            /* for L1 and L2 tables, in clusters */
+    uint32_t header_size;           /* in clusters */
+
+    uint64_t features;              /* format feature bits */
+    uint64_t compat_features;       /* compatible feature bits */
+    uint64_t autoclear_features;    /* self-resetting feature bits */
+
+    uint64_t l1_table_offset;       /* in bytes */
+    uint64_t image_size;            /* total logical image size, in bytes */
+
+    /* if (features & QED_F_BACKING_FILE) */
+    uint32_t backing_filename_offset; /* in bytes from start of header */
+    uint32_t backing_filename_size;   /* in bytes */
+} QEDHeader;
+
+typedef struct {
+    uint64_t offsets[0];            /* in bytes */
+} QEDTable;
+
+/* The L2 cache is a simple write-through cache for L2 structures */
+typedef struct CachedL2Table {
+    QEDTable *table;
+    uint64_t offset;    /* offset=0 indicates an invalidate entry */
+    QTAILQ_ENTRY(CachedL2Table) node;
+    int ref;
+} CachedL2Table;
+
+typedef struct {
+    QTAILQ_HEAD(, CachedL2Table) entries;
+    unsigned int n_entries;
+} L2TableCache;
+
+typedef struct QEDRequest {
+    CachedL2Table *l2_table;
+} QEDRequest;
+
+enum {
+    QED_AIOCB_WRITE = 0x0001,       /* read or write? */
+    QED_AIOCB_ZERO  = 0x0002,       /* zero write, used with QED_AIOCB_WRITE */
+};
+
+typedef struct QEDAIOCB {
+    BlockDriverAIOCB common;
+    QEMUBH *bh;
+    int bh_ret;                     /* final return status for completion bh */
+    QSIMPLEQ_ENTRY(QEDAIOCB) next;  /* next request */
+    int flags;                      /* QED_AIOCB_* bits ORed together */
+    bool *finished;                 /* signal for cancel completion */
+    uint64_t end_pos;               /* request end on block device, in bytes */
+
+    /* User scatter-gather list */
+    QEMUIOVector *qiov;
+    size_t qiov_offset;             /* byte count already processed */
+
+    /* Current cluster scatter-gather list */
+    QEMUIOVector cur_qiov;
+    uint64_t cur_pos;               /* position on block device, in bytes */
+    uint64_t cur_cluster;           /* cluster offset in image file */
+    unsigned int cur_nclusters;     /* number of clusters being accessed */
+    int find_cluster_ret;           /* used for L1/L2 update */
+
+    QEDRequest request;
+} QEDAIOCB;
+
+typedef struct {
+    BlockDriverState *bs;           /* device */
+    uint64_t file_size;             /* length of image file, in bytes */
+
+    QEDHeader header;               /* always cpu-endian */
+    QEDTable *l1_table;
+    L2TableCache l2_cache;          /* l2 table cache */
+    uint32_t table_nelems;
+    uint32_t l1_shift;
+    uint32_t l2_shift;
+    uint32_t l2_mask;
+
+    /* Allocating write request queue */
+    QSIMPLEQ_HEAD(, QEDAIOCB) allocating_write_reqs;
+    bool allocating_write_reqs_plugged;
+
+    /* Periodic flush and clear need check flag */
+    QEMUTimer *need_check_timer;
+} BDRVQEDState;
+
+enum {
+    QED_CLUSTER_FOUND,         /* cluster found */
+    QED_CLUSTER_ZERO,          /* zero cluster found */
+    QED_CLUSTER_L2,            /* cluster missing in L2 */
+    QED_CLUSTER_L1,            /* cluster missing in L1 */
+};
+
+/**
+ * qed_find_cluster() completion callback
+ *
+ * @opaque:     User data for completion callback
+ * @ret:        QED_CLUSTER_FOUND   Success
+ *              QED_CLUSTER_L2      Data cluster unallocated in L2
+ *              QED_CLUSTER_L1      L2 unallocated in L1
+ *              -errno              POSIX error occurred
+ * @offset:     Data cluster offset
+ * @len:        Contiguous bytes starting from cluster offset
+ *
+ * This function is invoked when qed_find_cluster() completes.
+ *
+ * On success ret is QED_CLUSTER_FOUND and offset/len are a contiguous range
+ * in the image file.
+ *
+ * On failure ret is QED_CLUSTER_L2 or QED_CLUSTER_L1 for missing L2 or L1
+ * table offset, respectively.  len is number of contiguous unallocated bytes.
+ */
+typedef void QEDFindClusterFunc(void *opaque, int ret, uint64_t offset, size_t len);
+
+/**
+ * Generic callback for chaining async callbacks
+ */
+typedef struct {
+    BlockDriverCompletionFunc *cb;
+    void *opaque;
+} GenericCB;
+
+void *gencb_alloc(size_t len, BlockDriverCompletionFunc *cb, void *opaque);
+void gencb_complete(void *opaque, int ret);
+
+/**
+ * Header functions
+ */
+int qed_write_header_sync(BDRVQEDState *s);
+
+/**
+ * L2 cache functions
+ */
+void qed_init_l2_cache(L2TableCache *l2_cache);
+void qed_free_l2_cache(L2TableCache *l2_cache);
+CachedL2Table *qed_alloc_l2_cache_entry(L2TableCache *l2_cache);
+void qed_unref_l2_cache_entry(CachedL2Table *entry);
+CachedL2Table *qed_find_l2_cache_entry(L2TableCache *l2_cache, uint64_t offset);
+void qed_commit_l2_cache_entry(L2TableCache *l2_cache, CachedL2Table *l2_table);
+
+/**
+ * Table I/O functions
+ */
+int qed_read_l1_table_sync(BDRVQEDState *s);
+void qed_write_l1_table(BDRVQEDState *s, unsigned int index, unsigned int n,
+                        BlockDriverCompletionFunc *cb, void *opaque);
+int qed_write_l1_table_sync(BDRVQEDState *s, unsigned int index,
+                            unsigned int n);
+int qed_read_l2_table_sync(BDRVQEDState *s, QEDRequest *request,
+                           uint64_t offset);
+void qed_read_l2_table(BDRVQEDState *s, QEDRequest *request, uint64_t offset,
+                       BlockDriverCompletionFunc *cb, void *opaque);
+void qed_write_l2_table(BDRVQEDState *s, QEDRequest *request,
+                        unsigned int index, unsigned int n, bool flush,
+                        BlockDriverCompletionFunc *cb, void *opaque);
+int qed_write_l2_table_sync(BDRVQEDState *s, QEDRequest *request,
+                            unsigned int index, unsigned int n, bool flush);
+
+/**
+ * Cluster functions
+ */
+void qed_find_cluster(BDRVQEDState *s, QEDRequest *request, uint64_t pos,
+                      size_t len, QEDFindClusterFunc *cb, void *opaque);
+
+/**
+ * Consistency check
+ */
+int qed_check(BDRVQEDState *s, BdrvCheckResult *result, bool fix);
+
+QEDTable *qed_alloc_table(BDRVQEDState *s);
+
+/**
+ * Round down to the start of a cluster
+ */
+static inline uint64_t qed_start_of_cluster(BDRVQEDState *s, uint64_t offset)
+{
+    return offset & ~(uint64_t)(s->header.cluster_size - 1);
+}
+
+static inline uint64_t qed_offset_into_cluster(BDRVQEDState *s, uint64_t offset)
+{
+    return offset & (s->header.cluster_size - 1);
+}
+
+static inline uint64_t qed_bytes_to_clusters(BDRVQEDState *s, uint64_t bytes)
+{
+    return qed_start_of_cluster(s, bytes + (s->header.cluster_size - 1)) /
+           (s->header.cluster_size - 1);
+}
+
+static inline unsigned int qed_l1_index(BDRVQEDState *s, uint64_t pos)
+{
+    return pos >> s->l1_shift;
+}
+
+static inline unsigned int qed_l2_index(BDRVQEDState *s, uint64_t pos)
+{
+    return (pos >> s->l2_shift) & s->l2_mask;
+}
+
+/**
+ * Test if a cluster offset is valid
+ */
+static inline bool qed_check_cluster_offset(BDRVQEDState *s, uint64_t offset)
+{
+    uint64_t header_size = (uint64_t)s->header.header_size *
+                           s->header.cluster_size;
+
+    if (offset & (s->header.cluster_size - 1)) {
+        return false;
+    }
+    return offset >= header_size && offset < s->file_size;
+}
+
+/**
+ * Test if a table offset is valid
+ */
+static inline bool qed_check_table_offset(BDRVQEDState *s, uint64_t offset)
+{
+    uint64_t end_offset = offset + (s->header.table_size - 1) *
+                          s->header.cluster_size;
+
+    /* Overflow check */
+    if (end_offset <= offset) {
+        return false;
+    }
+
+    return qed_check_cluster_offset(s, offset) &&
+           qed_check_cluster_offset(s, end_offset);
+}
+
+static inline bool qed_offset_is_cluster_aligned(BDRVQEDState *s,
+                                                 uint64_t offset)
+{
+    if (qed_offset_into_cluster(s, offset)) {
+        return false;
+    }
+    return true;
+}
+
+static inline bool qed_offset_is_unalloc_cluster(uint64_t offset)
+{
+    if (offset == 0) {
+        return true;
+    }
+    return false;
+}
+
+static inline bool qed_offset_is_zero_cluster(uint64_t offset)
+{
+    if (offset == 1) {
+        return true;
+    }
+    return false;
+}
+
+#endif /* BLOCK_QED_H */
diff --git a/contrib/qemu/block/snapshot.c b/contrib/qemu/block/snapshot.c
new file mode 100644
index 000000000..6c6d9deea
--- /dev/null
+++ b/contrib/qemu/block/snapshot.c
@@ -0,0 +1,157 @@
+/*
+ * Block layer snapshot related functions
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "block/snapshot.h"
+#include "block/block_int.h"
+
+int bdrv_snapshot_find(BlockDriverState *bs, QEMUSnapshotInfo *sn_info,
+                       const char *name)
+{
+    QEMUSnapshotInfo *sn_tab, *sn;
+    int nb_sns, i, ret;
+
+    ret = -ENOENT;
+    nb_sns = bdrv_snapshot_list(bs, &sn_tab);
+    if (nb_sns < 0) {
+        return ret;
+    }
+    for (i = 0; i < nb_sns; i++) {
+        sn = &sn_tab[i];
+        if (!strcmp(sn->id_str, name) || !strcmp(sn->name, name)) {
+            *sn_info = *sn;
+            ret = 0;
+            break;
+        }
+    }
+    g_free(sn_tab);
+    return ret;
+}
+
+int bdrv_can_snapshot(BlockDriverState *bs)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs)) {
+        return 0;
+    }
+
+    if (!drv->bdrv_snapshot_create) {
+        if (bs->file != NULL) {
+            return bdrv_can_snapshot(bs->file);
+        }
+        return 0;
+    }
+
+    return 1;
+}
+
+int bdrv_snapshot_create(BlockDriverState *bs,
+                         QEMUSnapshotInfo *sn_info)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_create) {
+        return drv->bdrv_snapshot_create(bs, sn_info);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_create(bs->file, sn_info);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_goto(BlockDriverState *bs,
+                       const char *snapshot_id)
+{
+    BlockDriver *drv = bs->drv;
+    int ret, open_ret;
+
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_goto) {
+        return drv->bdrv_snapshot_goto(bs, snapshot_id);
+    }
+
+    if (bs->file) {
+        drv->bdrv_close(bs);
+        ret = bdrv_snapshot_goto(bs->file, snapshot_id);
+        open_ret = drv->bdrv_open(bs, NULL, bs->open_flags);
+        if (open_ret < 0) {
+            bdrv_delete(bs->file);
+            bs->drv = NULL;
+            return open_ret;
+        }
+        return ret;
+    }
+
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_delete(BlockDriverState *bs, const char *snapshot_id)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_delete) {
+        return drv->bdrv_snapshot_delete(bs, snapshot_id);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_delete(bs->file, snapshot_id);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_list(BlockDriverState *bs,
+                       QEMUSnapshotInfo **psn_info)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (drv->bdrv_snapshot_list) {
+        return drv->bdrv_snapshot_list(bs, psn_info);
+    }
+    if (bs->file) {
+        return bdrv_snapshot_list(bs->file, psn_info);
+    }
+    return -ENOTSUP;
+}
+
+int bdrv_snapshot_load_tmp(BlockDriverState *bs,
+        const char *snapshot_name)
+{
+    BlockDriver *drv = bs->drv;
+    if (!drv) {
+        return -ENOMEDIUM;
+    }
+    if (!bs->read_only) {
+        return -EINVAL;
+    }
+    if (drv->bdrv_snapshot_load_tmp) {
+        return drv->bdrv_snapshot_load_tmp(bs, snapshot_name);
+    }
+    return -ENOTSUP;
+}
diff --git a/contrib/qemu/config-host.h b/contrib/qemu/config-host.h
new file mode 100644
index 000000000..46b1595a8
--- /dev/null
+++ b/contrib/qemu/config-host.h
@@ -0,0 +1,73 @@
+/* Automatically generated by create_config - do not modify */
+#define CONFIG_QEMU_CONFDIR "/usr/local/etc/qemu"
+#define CONFIG_QEMU_DATADIR "/usr/local/share/qemu"
+#define CONFIG_QEMU_DOCDIR "/usr/local/share/doc/qemu"
+#define CONFIG_QEMU_LOCALSTATEDIR "/usr/local/var"
+#define CONFIG_QEMU_HELPERDIR "/usr/local/libexec"
+#define CONFIG_QEMU_LOCALEDIR "/usr/local/share/locale"
+#define HOST_X86_64 1
+#define CONFIG_QEMU_LDST_OPTIMIZATION 1
+#define CONFIG_POSIX 1
+#define CONFIG_LINUX 1
+#define CONFIG_SLIRP 1
+#define CONFIG_SMBD_COMMAND "/usr/sbin/smbd"
+#define CONFIG_AUDIO_DRIVERS \
+    &oss_audio_driver,\
+
+#define CONFIG_OSS 1
+#define CONFIG_BDRV_RW_WHITELIST\
+    NULL
+#define CONFIG_BDRV_RO_WHITELIST\
+    NULL
+#define CONFIG_VNC 1
+#define CONFIG_VNC_TLS 1
+#define CONFIG_VNC_SASL 1
+#define CONFIG_VNC_WS 1
+#define CONFIG_FNMATCH 1
+#define CONFIG_UUID 1
+#define CONFIG_XFS 1
+#define QEMU_VERSION "1.5.50"
+#define QEMU_PKGVERSION ""
+#define CONFIG_CURSES 1
+#define CONFIG_UTIMENSAT 1
+#define CONFIG_PIPE2 1
+#define CONFIG_ACCEPT4 1
+#define CONFIG_SPLICE 1
+#define CONFIG_EVENTFD 1
+#define CONFIG_FALLOCATE 1
+#define CONFIG_FALLOCATE_PUNCH_HOLE 1
+#define CONFIG_SYNC_FILE_RANGE 1
+#define CONFIG_FIEMAP 1
+#define CONFIG_DUP3 1
+#define CONFIG_EPOLL 1
+#define CONFIG_EPOLL_CREATE1 1
+#define CONFIG_EPOLL_PWAIT 1
+#define CONFIG_SENDFILE 1
+#define CONFIG_INOTIFY 1
+#define CONFIG_INOTIFY1 1
+#define CONFIG_BYTESWAP_H 1
+#define CONFIG_CURL 1
+#define CONFIG_LINUX_AIO 1
+#define CONFIG_ATTR 1
+#define CONFIG_VHOST_SCSI 1
+#define CONFIG_IOVEC 1
+#define CONFIG_PREADV 1
+#define CONFIG_FDT 1
+#define CONFIG_SIGNALFD 1
+#define CONFIG_FDATASYNC 1
+#define CONFIG_MADVISE 1
+#define CONFIG_POSIX_MADVISE 1
+#define CONFIG_SIGEV_THREAD_ID 1
+#define CONFIG_UNAME_RELEASE ""
+#define CONFIG_QOM_CAST_DEBUG 1
+#define CONFIG_COROUTINE_BACKEND ucontext
+#define CONFIG_OPEN_BY_HANDLE 1
+#define CONFIG_LINUX_MAGIC_H 1
+#define CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE 1
+#define CONFIG_HAS_ENVIRON 1
+#define CONFIG_CPUID_H 1
+#define CONFIG_INT128 1
+#define CONFIG_VIRTIO_BLK_DATA_PLANE $(CONFIG_VIRTIO)
+#define CONFIG_TRACE_NOP 1
+#define CONFIG_TRACE_FILE trace
+#define CONFIG_TRACE_DEFAULT 1
diff --git a/contrib/qemu/coroutine-ucontext.c b/contrib/qemu/coroutine-ucontext.c
new file mode 100644
index 000000000..4bf2cde27
--- /dev/null
+++ b/contrib/qemu/coroutine-ucontext.c
@@ -0,0 +1,225 @@
+/*
+ * ucontext coroutine initialization code
+ *
+ * Copyright (C) 2006  Anthony Liguori <anthony@codemonkey.ws>
+ * Copyright (C) 2011  Kevin Wolf <kwolf@redhat.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.0 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <
author	Ravishankar N <ravishankar@redhat.com>	2016-11-26 21:24:01 +0530
committer	Pranith Kumar Karampuri <pkarampu@redhat.com>	2016-11-27 23:51:59 -0800
commit	a07ddd8fcc8dcdcf7ccfa61211d258f13b9f9229 (patch)
tree	8192cfc5b2553043dc9511b386bf8894c7972746 /tests/basic/afr
parent	2214501d6045b45dde469c5a476c86b6cf464c34 (diff)