add pump xlator and changes for replace-brick

Signed-off-by: Pavan Vilas Sondur <pavan@gluster.com>
Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

BUG: 1235 (Bug for all pump/migrate commits)
URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1235

1 files changed, 2642 insertions, 0 deletions

diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
new file mode 100644
index 000000000..aeadceddb
--- /dev/null
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -0,0 +1,2642 @@
+/*
+   Copyright (c) 2007-2009 Gluster, Inc. <http://www.gluster.com>
+   This file is part of GlusterFS.
+
+   GlusterFS is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published
+   by the Free Software Foundation; either version 3 of the License,
+   or (at your option) any later version.
+
+   GlusterFS 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
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see
+   <http://www.gnu.org/licenses/>.
+*/
+
+#include <libgen.h>
+#include <unistd.h>
+#include <fnmatch.h>
+#include <sys/time.h>
+#include <stdlib.h>
+#include <signal.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "glusterfs.h"
+#include "afr.h"
+#include "dict.h"
+#include "xlator.h"
+#include "hashfn.h"
+#include "logging.h"
+#include "stack.h"
+#include "list.h"
+#include "call-stub.h"
+#include "defaults.h"
+#include "common-utils.h"
+#include "compat-errno.h"
+#include "compat.h"
+#include "byte-order.h"
+#include "statedump.h"
+
+#include "fd.h"
+
+#include "afr-inode-read.h"
+#include "afr-inode-write.h"
+#include "afr-dir-read.h"
+#include "afr-dir-write.h"
+#include "afr-transaction.h"
+#include "afr-self-heal.h"
+#include "afr-self-heal-common.h"
+#include "pump.h"
+
+#define AFR_ICTX_OPENDIR_DONE_MASK     0x0000000200000000ULL
+#define AFR_ICTX_SPLIT_BRAIN_MASK      0x0000000100000000ULL
+#define AFR_ICTX_READ_CHILD_MASK       0x00000000FFFFFFFFULL
+
+void
+afr_set_lk_owner (call_frame_t *frame, xlator_t *this)
+{
+        if (!frame->root->lk_owner) {
+                gf_log (this->name, GF_LOG_TRACE,
+                        "Setting lk-owner=%llu",
+                        (unsigned long long) frame->root);
+                frame->root->lk_owner = (uint64_t) frame->root;
+        }
+}
+
+uint64_t
+afr_is_split_brain (xlator_t *this, inode_t *inode)
+{
+        int ret = 0;
+
+        uint64_t ctx         = 0;
+        uint64_t split_brain = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0)
+                        goto unlock;
+
+                split_brain = ctx & AFR_ICTX_SPLIT_BRAIN_MASK;
+        }
+unlock:
+        UNLOCK (&inode->lock);
+
+out:
+        return split_brain;
+}
+
+
+void
+afr_set_split_brain (xlator_t *this, inode_t *inode, gf_boolean_t set)
+{
+        uint64_t ctx = 0;
+        int      ret = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0) {
+                        ctx = 0;
+                }
+
+                if (set) {
+			ctx = (~AFR_ICTX_SPLIT_BRAIN_MASK & ctx)
+                                | (0xFFFFFFFFFFFFFFFFULL & AFR_ICTX_SPLIT_BRAIN_MASK);
+		} else {
+			ctx = (~AFR_ICTX_SPLIT_BRAIN_MASK & ctx);
+		}
+                __inode_ctx_put (inode, this, ctx);
+        }
+        UNLOCK (&inode->lock);
+out:
+        return;
+}
+
+
+uint64_t
+afr_is_opendir_done (xlator_t *this, inode_t *inode)
+{
+        int ret = 0;
+
+        uint64_t ctx          = 0;
+        uint64_t opendir_done = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0)
+                        goto unlock;
+
+                opendir_done = ctx & AFR_ICTX_OPENDIR_DONE_MASK;
+        }
+unlock:
+        UNLOCK (&inode->lock);
+
+out:
+        return opendir_done;
+}
+
+
+void
+afr_set_opendir_done (xlator_t *this, inode_t *inode)
+{
+        uint64_t ctx = 0;
+        int      ret = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0) {
+                        ctx = 0;
+                }
+
+                ctx = (~AFR_ICTX_OPENDIR_DONE_MASK & ctx)
+                        | (0xFFFFFFFFFFFFFFFFULL & AFR_ICTX_OPENDIR_DONE_MASK);
+
+                __inode_ctx_put (inode, this, ctx);
+        }
+        UNLOCK (&inode->lock);
+out:
+        return;
+}
+
+
+uint64_t
+afr_read_child (xlator_t *this, inode_t *inode)
+{
+        int ret = 0;
+
+        uint64_t ctx         = 0;
+        uint64_t read_child  = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0)
+                        goto unlock;
+
+                read_child = ctx & AFR_ICTX_READ_CHILD_MASK;
+        }
+unlock:
+        UNLOCK (&inode->lock);
+
+out:
+        return read_child;
+}
+
+
+void
+afr_set_read_child (xlator_t *this, inode_t *inode, int32_t read_child)
+{
+        uint64_t ctx = 0;
+        int      ret = 0;
+
+        VALIDATE_OR_GOTO (inode, out);
+
+        LOCK (&inode->lock);
+        {
+                ret = __inode_ctx_get (inode, this, &ctx);
+
+                if (ret < 0) {
+                        ctx = 0;
+                }
+
+                ctx = (~AFR_ICTX_READ_CHILD_MASK & ctx)
+                        | (AFR_ICTX_READ_CHILD_MASK & read_child);
+
+                __inode_ctx_put (inode, this, ctx);
+        }
+        UNLOCK (&inode->lock);
+
+out:
+        return;
+}
+
+
+/**
+ * afr_local_cleanup - cleanup everything in frame->local
+ */
+
+void
+afr_local_sh_cleanup (afr_local_t *local, xlator_t *this)
+{
+	afr_self_heal_t *sh = NULL;
+	afr_private_t   *priv = NULL;
+	int              i = 0;
+
+
+	sh = &local->self_heal;
+	priv = this->private;
+
+	if (sh->buf)
+		GF_FREE (sh->buf);
+
+	if (sh->xattr) {
+		for (i = 0; i < priv->child_count; i++) {
+			if (sh->xattr[i]) {
+				dict_unref (sh->xattr[i]);
+				sh->xattr[i] = NULL;
+			}
+		}
+		GF_FREE (sh->xattr);
+	}
+
+	if (sh->child_errno)
+		GF_FREE (sh->child_errno);
+
+	if (sh->pending_matrix) {
+		for (i = 0; i < priv->child_count; i++) {
+			GF_FREE (sh->pending_matrix[i]);
+		}
+		GF_FREE (sh->pending_matrix);
+	}
+
+	if (sh->delta_matrix) {
+		for (i = 0; i < priv->child_count; i++) {
+			GF_FREE (sh->delta_matrix[i]);
+		}
+		GF_FREE (sh->delta_matrix);
+	}
+
+	if (sh->sources)
+		GF_FREE (sh->sources);
+
+	if (sh->success)
+		GF_FREE (sh->success);
+
+	if (sh->locked_nodes)
+		GF_FREE (sh->locked_nodes);
+
+	if (sh->healing_fd && !sh->healing_fd_opened) {
+		fd_unref (sh->healing_fd);
+		sh->healing_fd = NULL;
+	}
+
+        if (sh->linkname)
+                GF_FREE ((char *)sh->linkname);
+
+	loc_wipe (&sh->parent_loc);
+}
+
+
+void
+afr_local_transaction_cleanup (afr_local_t *local, xlator_t *this)
+{
+        int             i = 0;
+        afr_private_t * priv = NULL;
+
+        priv = this->private;
+
+        for (i = 0; i < priv->child_count; i++) {
+                if (local->pending && local->pending[i])
+                        GF_FREE (local->pending[i]);
+        }
+
+        GF_FREE (local->pending);
+
+	GF_FREE (local->transaction.locked_nodes);
+	GF_FREE (local->transaction.child_errno);
+	GF_FREE (local->child_errno);
+
+	GF_FREE (local->transaction.basename);
+	GF_FREE (local->transaction.new_basename);
+
+	loc_wipe (&local->transaction.parent_loc);
+	loc_wipe (&local->transaction.new_parent_loc);
+}
+
+
+void
+afr_local_cleanup (afr_local_t *local, xlator_t *this)
+{
+        int i;
+        afr_private_t * priv = NULL;
+
+	if (!local)
+		return;
+
+	afr_local_sh_cleanup (local, this);
+
+        afr_local_transaction_cleanup (local, this);
+
+        priv = this->private;
+
+	loc_wipe (&local->loc);
+	loc_wipe (&local->newloc);
+
+	if (local->fd)
+		fd_unref (local->fd);
+
+	if (local->xattr_req)
+		dict_unref (local->xattr_req);
+
+	GF_FREE (local->child_up);
+
+	{ /* lookup */
+                if (local->cont.lookup.xattrs) {
+                        for (i = 0; i < priv->child_count; i++) {
+                                if (local->cont.lookup.xattrs[i]) {
+                                        dict_unref (local->cont.lookup.xattrs[i]);
+                                        local->cont.lookup.xattrs[i] = NULL;
+                                }
+                        }
+                        GF_FREE (local->cont.lookup.xattrs);
+                        local->cont.lookup.xattrs = NULL;
+                }
+
+		if (local->cont.lookup.xattr) {
+                        dict_unref (local->cont.lookup.xattr);
+                }
+
+                if (local->cont.lookup.inode) {
+                        inode_unref (local->cont.lookup.inode);
+                }
+	}
+
+	{ /* getxattr */
+		if (local->cont.getxattr.name)
+			GF_FREE (local->cont.getxattr.name);
+	}
+
+	{ /* lk */
+		if (local->cont.lk.locked_nodes)
+			GF_FREE (local->cont.lk.locked_nodes);
+	}
+
+	{ /* create */
+		if (local->cont.create.fd)
+			fd_unref (local->cont.create.fd);
+	}
+
+	{ /* writev */
+		GF_FREE (local->cont.writev.vector);
+	}
+
+	{ /* setxattr */
+		if (local->cont.setxattr.dict)
+			dict_unref (local->cont.setxattr.dict);
+	}
+
+	{ /* removexattr */
+		GF_FREE (local->cont.removexattr.name);
+	}
+
+	{ /* symlink */
+		GF_FREE (local->cont.symlink.linkpath);
+	}
+
+        { /* opendir */
+                if (local->cont.opendir.checksum)
+                        GF_FREE (local->cont.opendir.checksum);
+        }
+}
+
+
+int
+afr_frame_return (call_frame_t *frame)
+{
+	afr_local_t *local = NULL;
+	int          call_count = 0;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		call_count = --local->call_count;
+	}
+	UNLOCK (&frame->lock);
+
+	return call_count;
+}
+
+
+/**
+ * up_children_count - return the number of children that are up
+ */
+
+int
+afr_up_children_count (int child_count, unsigned char *child_up)
+{
+	int i   = 0;
+	int ret = 0;
+
+	for (i = 0; i < child_count; i++)
+		if (child_up[i])
+			ret++;
+	return ret;
+}
+
+
+int
+afr_locked_nodes_count (unsigned char *locked_nodes, int child_count)
+{
+	int ret = 0;
+	int i;
+
+	for (i = 0; i < child_count; i++)
+		if (locked_nodes[i])
+			ret++;
+
+	return ret;
+}
+
+
+ino64_t
+afr_itransform (ino64_t ino, int child_count, int child_index)
+{
+	ino64_t scaled_ino = -1;
+
+	if (ino == ((uint64_t) -1)) {
+		scaled_ino = ((uint64_t) -1);
+		goto out;
+	}
+
+	scaled_ino = (ino * child_count) + child_index;
+
+out:
+	return scaled_ino;
+}
+
+
+int
+afr_deitransform_orig (ino64_t ino, int child_count)
+{
+	int index = -1;
+
+	index = ino % child_count;
+
+	return index;
+}
+
+
+int
+afr_deitransform (ino64_t ino, int child_count)
+{
+	return 0;
+}
+
+
+int
+afr_self_heal_lookup_unwind (call_frame_t *frame, xlator_t *this)
+{
+	afr_local_t *local = NULL;
+
+	local = frame->local;
+
+	if (local->govinda_gOvinda) {
+                afr_set_split_brain (this, local->cont.lookup.inode, _gf_true);
+	}
+
+	AFR_STACK_UNWIND (lookup, frame, local->op_ret, local->op_errno,
+			  local->cont.lookup.inode,
+			  &local->cont.lookup.buf,
+			  local->cont.lookup.xattr,
+                          &local->cont.lookup.postparent);
+
+	return 0;
+}
+
+
+static void
+afr_lookup_collect_xattr (afr_local_t *local, xlator_t *this,
+                          int child_index, dict_t *xattr)
+{
+	uint32_t        open_fd_count = 0;
+        uint32_t        inodelk_count = 0;
+        uint32_t        entrylk_count = 0;
+
+        int ret = 0;
+
+        if (afr_sh_has_metadata_pending (xattr, child_index, this)) {
+                local->self_heal.need_metadata_self_heal = _gf_true;
+                gf_log(this->name, GF_LOG_DEBUG,
+                       "metadata self-heal is pending for %s.",
+                       local->loc.path);
+        }
+
+        if (afr_sh_has_entry_pending (xattr, child_index, this)) {
+                local->self_heal.need_entry_self_heal = _gf_true;
+                gf_log(this->name, GF_LOG_DEBUG,
+                       "entry self-heal is pending for %s.", local->loc.path);
+        }
+
+        if (afr_sh_has_data_pending (xattr, child_index, this)) {
+                local->self_heal.need_data_self_heal = _gf_true;
+                gf_log(this->name, GF_LOG_DEBUG,
+                       "data self-heal is pending for %s.", local->loc.path);
+        }
+
+        ret = dict_get_uint32 (xattr, GLUSTERFS_OPEN_FD_COUNT,
+                               &open_fd_count);
+        if (ret == 0)
+                local->open_fd_count += open_fd_count;
+
+        ret = dict_get_uint32 (xattr, GLUSTERFS_INODELK_COUNT,
+                               &inodelk_count);
+        if (ret == 0)
+                local->inodelk_count += inodelk_count;
+
+        ret = dict_get_uint32 (xattr, GLUSTERFS_ENTRYLK_COUNT,
+                               &entrylk_count);
+        if (ret == 0)
+                local->entrylk_count += entrylk_count;
+}
+
+
+static void
+afr_lookup_self_heal_check (xlator_t *this, afr_local_t *local,
+                            struct iatt *buf, struct iatt *lookup_buf)
+{
+        if (FILETYPE_DIFFERS (buf, lookup_buf)) {
+                /* mismatching filetypes with same name
+                */
+
+                gf_log (this->name, GF_LOG_NORMAL,
+                        "filetype differs for %s ", local->loc.path);
+
+                local->govinda_gOvinda = 1;
+        }
+
+        if (PERMISSION_DIFFERS (buf, lookup_buf)) {
+                /* mismatching permissions */
+                gf_log (this->name, GF_LOG_NORMAL,
+                        "permissions differ for %s ", local->loc.path);
+                local->self_heal.need_metadata_self_heal = _gf_true;
+        }
+
+        if (OWNERSHIP_DIFFERS (buf, lookup_buf)) {
+                /* mismatching permissions */
+                local->self_heal.need_metadata_self_heal = _gf_true;
+                gf_log (this->name, GF_LOG_NORMAL,
+                        "ownership differs for %s ", local->loc.path);
+        }
+
+        if (SIZE_DIFFERS (buf, lookup_buf)
+            && IA_ISREG (buf->ia_type)) {
+                gf_log (this->name, GF_LOG_NORMAL,
+                        "size differs for %s ", local->loc.path);
+                local->self_heal.need_data_self_heal = _gf_true;
+        }
+
+}
+
+
+static void
+afr_lookup_done (call_frame_t *frame, xlator_t *this, struct iatt *lookup_buf)
+{
+        int  unwind = 1;
+        int  source = -1;
+        char sh_type_str[256] = {0,};
+
+        afr_local_t *local = NULL;
+
+        local = frame->local;
+
+        local->cont.lookup.postparent.ia_ino  = local->cont.lookup.parent_ino;
+
+        if (local->cont.lookup.ino) {
+                local->cont.lookup.buf.ia_ino = local->cont.lookup.ino;
+                local->cont.lookup.buf.ia_gen = local->cont.lookup.gen;
+        }
+
+        if (local->op_ret == 0) {
+                /* KLUDGE: assuming DHT will not itransform in
+                   revalidate */
+                if (local->cont.lookup.inode->ino) {
+                        local->cont.lookup.buf.ia_ino =
+                                local->cont.lookup.inode->ino;
+                        local->cont.lookup.buf.ia_gen =
+                                local->cont.lookup.inode->generation;
+                }
+        }
+
+        if (local->success_count && local->enoent_count) {
+                local->self_heal.need_metadata_self_heal = _gf_true;
+                local->self_heal.need_data_self_heal     = _gf_true;
+                local->self_heal.need_entry_self_heal    = _gf_true;
+                gf_log(this->name, GF_LOG_NORMAL,
+                       "entries are missing in lookup of %s.",
+                       local->loc.path);
+        }
+
+        if (local->success_count) {
+                /* check for split-brain case in previous lookup */
+                if (afr_is_split_brain (this,
+                                        local->cont.lookup.inode)) {
+                        local->self_heal.need_data_self_heal = _gf_true;
+                        gf_log(this->name, GF_LOG_NORMAL,
+                               "split brain detected during lookup of "
+                               "%s.", local->loc.path);
+                }
+        }
+
+        if ((local->self_heal.need_metadata_self_heal
+             || local->self_heal.need_data_self_heal
+             || local->self_heal.need_entry_self_heal)
+            && ((!local->cont.lookup.is_revalidate)
+                || (local->op_ret != -1))) {
+
+                if (local->open_fd_count
+                    || local->inodelk_count
+                    || local->entrylk_count) {
+
+                        /* Someone else is doing self-heal on this file.
+                           So just make a best effort to set the read-subvolume
+                           and return */
+
+                        if (IA_ISREG (local->cont.lookup.inode->ia_type)) {
+                                source = afr_self_heal_get_source (this, local, local->cont.lookup.xattrs);
+
+                                if (source >= 0) {
+                                        afr_set_read_child (this,
+                                                            local->cont.lookup.inode,
+                                                            source);
+                                }
+                        }
+                } else {
+                        if (!local->cont.lookup.inode->ia_type) {
+                                /* fix for RT #602 */
+                                local->cont.lookup.inode->ia_type =
+                                        lookup_buf->ia_type;
+                        }
+
+                        local->self_heal.background = _gf_true;
+                        local->self_heal.type       = local->cont.lookup.buf.ia_type;
+                        local->self_heal.unwind     = afr_self_heal_lookup_unwind;
+
+                        unwind = 0;
+
+                        afr_self_heal_type_str_get(&local->self_heal,
+                                                   sh_type_str,
+                                                   sizeof(sh_type_str));
+
+                        gf_log (this->name, GF_LOG_NORMAL, "background %s "
+                                "self-heal triggered. path: %s",
+                                sh_type_str, local->loc.path);
+
+                        afr_self_heal (frame, this);
+                }
+        }
+
+        if (unwind) {
+                AFR_STACK_UNWIND (lookup, frame, local->op_ret,
+                                  local->op_errno,
+                                  local->cont.lookup.inode,
+                                  &local->cont.lookup.buf,
+                                  local->cont.lookup.xattr,
+                                  &local->cont.lookup.postparent);
+        }
+}
+
+
+/*
+ * During a lookup, some errors are more "important" than
+ * others in that they must be given higher priority while
+ * returning to the user.
+ *
+ * The hierarchy is ESTALE > ENOENT > others
+ *
+ */
+
+static gf_boolean_t
+__error_more_important (int32_t old_errno, int32_t new_errno)
+{
+        gf_boolean_t ret = _gf_true;
+
+        /* Nothing should ever overwrite ESTALE */
+        if (old_errno == ESTALE)
+                ret = _gf_false;
+
+        /* Nothing should overwrite ENOENT, except ESTALE */
+        else if ((old_errno == ENOENT) && (new_errno != ESTALE))
+                ret = _gf_false;
+
+        return ret;
+}
+
+
+int
+afr_fresh_lookup_cbk (call_frame_t *frame, void *cookie,
+                      xlator_t *this,  int32_t op_ret,	int32_t op_errno,
+                      inode_t *inode,	struct iatt *buf, dict_t *xattr,
+                      struct iatt *postparent)
+{
+	afr_local_t *   local = NULL;
+	afr_private_t * priv  = NULL;
+	struct iatt *   lookup_buf = NULL;
+
+	int             call_count      = -1;
+	int             child_index     = -1;
+        int             first_up_child  = -1;
+
+	child_index = (long) cookie;
+	priv = this->private;
+
+	LOCK (&frame->lock);
+	{
+		local = frame->local;
+
+                lookup_buf = &local->cont.lookup.buf;
+
+		if (op_ret == -1) {
+			if (op_errno == ENOENT)
+				local->enoent_count++;
+
+                        if (__error_more_important (local->op_errno, op_errno))
+                                local->op_errno = op_errno;
+
+                        if (local->op_errno == ESTALE) {
+                                local->op_ret = -1;
+                        }
+
+                        goto unlock;
+		}
+
+                afr_lookup_collect_xattr (local, this, child_index, xattr);
+
+                first_up_child = afr_first_up_child (priv);
+
+                if (child_index == first_up_child) {
+                        local->cont.lookup.ino =
+                                afr_itransform (buf->ia_ino,
+                                                priv->child_count,
+                                                first_up_child);
+                        local->cont.lookup.gen = buf->ia_gen;
+                }
+
+		if (local->success_count == 0) {
+                        if (local->op_errno != ESTALE)
+                                local->op_ret = op_ret;
+
+			local->cont.lookup.inode               = inode_ref (inode);
+			local->cont.lookup.xattr               = dict_ref (xattr);
+			local->cont.lookup.xattrs[child_index] = dict_ref (xattr);
+                        local->cont.lookup.postparent          = *postparent;
+
+                        if (priv->first_lookup && inode->ino == 1) {
+                                gf_log (this->name, GF_LOG_TRACE,
+                                        "added root inode");
+                                priv->root_inode = inode_ref (inode);
+                                priv->first_lookup = 0;
+                                priv->child_up[1] = 0;
+
+                                LOCK (&priv->lock);
+                                {
+                                        priv->down_count++;
+                                }
+                                UNLOCK (&priv->lock);
+
+                        }
+
+                        *lookup_buf = *buf;
+
+                        lookup_buf->ia_ino = afr_itransform (buf->ia_ino,
+                                                             priv->child_count,
+                                                             child_index);
+                        if (priv->read_child >= 0) {
+                                afr_set_read_child (this,
+                                                    local->cont.lookup.inode,
+                                                    priv->read_child);
+                        } else {
+                                afr_set_read_child (this,
+                                                    local->cont.lookup.inode,
+                                                    child_index);
+                        }
+
+		} else {
+                        afr_lookup_self_heal_check (this, local, buf, lookup_buf);
+
+                        if (child_index == local->read_child_index) {
+                                /*
+                                   lookup has succeeded on the read child.
+                                   So use its inode number
+                                */
+                                if (local->cont.lookup.xattr)
+                                        dict_unref (local->cont.lookup.xattr);
+
+                                local->cont.lookup.xattr = dict_ref (xattr);
+                                local->cont.lookup.xattrs[child_index] = dict_ref (xattr);
+                                local->cont.lookup.postparent          = *postparent;
+
+                                *lookup_buf = *buf;
+
+                                if (priv->read_child >= 0) {
+                                        afr_set_read_child (this,
+                                                            local->cont.lookup.inode,
+                                                            priv->read_child);
+                                } else {
+                                        afr_set_read_child (this,
+                                                            local->cont.lookup.inode,
+                                                            local->read_child_index);
+                                }
+                        }
+
+		}
+
+		local->success_count++;
+	}
+unlock:
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0) {
+                afr_lookup_done (frame, this, lookup_buf);
+	}
+
+	return 0;
+}
+
+
+int
+afr_revalidate_lookup_cbk (call_frame_t *frame, void *cookie,
+                           xlator_t *this, int32_t op_ret, int32_t op_errno,
+                           inode_t *inode, struct iatt *buf, dict_t *xattr,
+                           struct iatt *postparent)
+{
+	afr_local_t *   local = NULL;
+	afr_private_t * priv  = NULL;
+	struct iatt *   lookup_buf = NULL;
+
+	int             call_count      = -1;
+	int             child_index     = -1;
+        int             first_up_child  = -1;
+
+	child_index = (long) cookie;
+	priv = this->private;
+
+	LOCK (&frame->lock);
+	{
+		local = frame->local;
+
+		lookup_buf = &local->cont.lookup.buf;
+
+		if (op_ret == -1) {
+			if (op_errno == ENOENT)
+				local->enoent_count++;
+
+                        if (__error_more_important (local->op_errno, op_errno))
+                            local->op_errno = op_errno;
+
+                            if (local->op_errno == ESTALE) {
+                                    local->op_ret = -1;
+                            }
+
+                            goto unlock;
+                }
+
+                afr_lookup_collect_xattr (local, this, child_index, xattr);
+
+                first_up_child = afr_first_up_child (priv);
+
+                if (child_index == first_up_child) {
+                        local->cont.lookup.ino =
+                                afr_itransform (buf->ia_ino,
+                                                priv->child_count,
+                                                first_up_child);
+                        local->cont.lookup.gen = buf->ia_gen;
+                }
+
+		/* in case of revalidate, we need to send stat of the
+		 * child whose stat was sent during the first lookup.
+		 * (so that time stamp does not vary with revalidate.
+		 * in case it is down, stat of the fist success will
+		 * be replied */
+
+		/* inode number should be preserved across revalidates */
+
+		if (local->success_count == 0) {
+                        if (local->op_errno != ESTALE)
+                                local->op_ret = op_ret;
+
+			local->cont.lookup.inode               = inode_ref (inode);
+			local->cont.lookup.xattr               = dict_ref (xattr);
+			local->cont.lookup.xattrs[child_index] = dict_ref (xattr);
+                        local->cont.lookup.postparent          = *postparent;
+
+			*lookup_buf = *buf;
+
+                        lookup_buf->ia_ino = afr_itransform (buf->ia_ino,
+                                                             priv->child_count,
+                                                             child_index);
+
+                        if (priv->read_child >= 0) {
+                                afr_set_read_child (this,
+                                                    local->cont.lookup.inode,
+                                                    priv->read_child);
+                        } else {
+                                afr_set_read_child (this,
+                                                    local->cont.lookup.inode,
+                                                    child_index);
+                        }
+
+		} else {
+                        afr_lookup_self_heal_check (this, local, buf, lookup_buf);
+
+                        if (child_index == local->read_child_index) {
+
+                                /*
+                                   lookup has succeeded on the read child.
+                                   So use its inode number
+                                */
+
+                                if (local->cont.lookup.xattr)
+                                        dict_unref (local->cont.lookup.xattr);
+
+                                local->cont.lookup.xattr               = dict_ref (xattr);
+                                local->cont.lookup.xattrs[child_index] = dict_ref (xattr);
+                                local->cont.lookup.postparent          = *postparent;
+
+                                *lookup_buf = *buf;
+
+                                if (priv->read_child >= 0) {
+                                        afr_set_read_child (this,
+                                                            local->cont.lookup.inode,
+                                                            priv->read_child);
+                                } else {
+                                        afr_set_read_child (this,
+                                                            local->cont.lookup.inode,
+                                                            local->read_child_index);
+                                }
+                        }
+
+		}
+
+		local->success_count++;
+	}
+unlock:
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0) {
+                afr_lookup_done (frame, this, lookup_buf);
+	}
+
+	return 0;
+}
+
+
+int
+afr_lookup (call_frame_t *frame, xlator_t *this,
+	    loc_t *loc, dict_t *xattr_req)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t   *local = NULL;
+	int            ret = -1;
+	int            i = 0;
+
+        fop_lookup_cbk_t callback;
+
+        int call_count = 0;
+
+        uint64_t       ctx;
+
+	int32_t        op_errno = 0;
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	local->op_ret = -1;
+
+	frame->local = local;
+
+        if (!strcmp (loc->path, "/" GF_REPLICATE_TRASH_DIR)) {
+                op_errno = ENOENT;
+                goto out;
+        }
+
+	loc_copy (&local->loc, loc);
+
+        ret = inode_ctx_get (loc->inode, this, &ctx);
+        if (ret == 0) {
+                /* lookup is a revalidate */
+
+                callback = afr_revalidate_lookup_cbk;
+
+                local->cont.lookup.is_revalidate = _gf_true;
+                local->read_child_index          = afr_read_child (this,
+                                                                   loc->inode);
+        } else {
+                callback = afr_fresh_lookup_cbk;
+
+                LOCK (&priv->read_child_lock);
+                {
+                        local->read_child_index = (++priv->read_child_rr)
+                                % (priv->child_count);
+                }
+                UNLOCK (&priv->read_child_lock);
+        }
+
+        if (loc->parent)
+                local->cont.lookup.parent_ino = loc->parent->ino;
+
+	local->child_up = memdup (priv->child_up, priv->child_count);
+
+        local->cont.lookup.xattrs = GF_CALLOC (priv->child_count,
+                                    sizeof (*local->cont.lookup.xattr),
+                                    gf_afr_mt_dict_t);
+
+	local->call_count = afr_up_children_count (priv->child_count,
+                                                   local->child_up);
+        call_count = local->call_count;
+
+        if (local->call_count == 0) {
+                ret      = -1;
+                op_errno = ENOTCONN;
+                goto out;
+        }
+
+	/* By default assume ENOTCONN. On success it will be set to 0. */
+	local->op_errno = ENOTCONN;
+
+	if (xattr_req == NULL)
+		local->xattr_req = dict_new ();
+	else
+		local->xattr_req = dict_ref (xattr_req);
+
+        for (i = 0; i < priv->child_count; i++) {
+		ret = dict_set_uint64 (local->xattr_req, priv->pending_key[i],
+				       3 * sizeof(int32_t));
+
+                /* 3 = data+metadata+entry */
+        }
+
+	ret = dict_set_uint64 (local->xattr_req, GLUSTERFS_OPEN_FD_COUNT, 0);
+        ret = dict_set_uint64 (local->xattr_req, GLUSTERFS_INODELK_COUNT, 0);
+        ret = dict_set_uint64 (local->xattr_req, GLUSTERFS_ENTRYLK_COUNT, 0);
+
+	for (i = 0; i < priv->child_count; i++) {
+                if (local->child_up[i]) {
+                        STACK_WIND_COOKIE (frame, callback, (void *) (long) i,
+                                           priv->children[i],
+                                           priv->children[i]->fops->lookup,
+                                           loc, local->xattr_req);
+                        if (!--call_count)
+                                break;
+                }
+	}
+
+	ret = 0;
+out:
+	if (ret == -1)
+		AFR_STACK_UNWIND (lookup, frame, -1, op_errno,
+                                  NULL, NULL, NULL, NULL);
+
+	return 0;
+}
+
+
+/* {{{ open */
+
+int
+afr_fd_ctx_set (xlator_t *this, fd_t *fd)
+{
+        afr_private_t * priv = NULL;
+
+        int op_ret = 0;
+        int ret    = 0;
+
+        uint64_t       ctx;
+        afr_fd_ctx_t * fd_ctx = NULL;
+
+        VALIDATE_OR_GOTO (this->private, out);
+        VALIDATE_OR_GOTO (fd, out);
+
+        priv = this->private;
+
+        LOCK (&fd->lock);
+        {
+                ret = __fd_ctx_get (fd, this, &ctx);
+
+                if (ret == 0)
+                        goto unlock;
+
+                fd_ctx = GF_CALLOC (1, sizeof (afr_fd_ctx_t),
+                                    gf_afr_mt_afr_fd_ctx_t);
+                if (!fd_ctx) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Out of memory");
+
+                        op_ret = -ENOMEM;
+                        goto unlock;
+                }
+
+                fd_ctx->pre_op_done = GF_CALLOC (sizeof (*fd_ctx->pre_op_done),
+                                                 priv->child_count,
+                                                 gf_afr_mt_char);
+                if (!fd_ctx->pre_op_done) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Out of memory");
+                        op_ret = -ENOMEM;
+                        goto unlock;
+                }
+
+                fd_ctx->opened_on = GF_CALLOC (sizeof (*fd_ctx->opened_on),
+                                               priv->child_count,
+                                               gf_afr_mt_char);
+                if (!fd_ctx->opened_on) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Out of memory");
+                        op_ret = -ENOMEM;
+                        goto unlock;
+                }
+
+                fd_ctx->child_failed = GF_CALLOC (
+                                         sizeof (*fd_ctx->child_failed),
+                                         priv->child_count,
+                                         gf_afr_mt_char);
+
+                if (!fd_ctx->child_failed) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Out of memory");
+
+                        op_ret = -ENOMEM;
+                        goto unlock;
+                }
+
+                fd_ctx->up_count   = priv->up_count;
+                fd_ctx->down_count = priv->down_count;
+
+                ret = __fd_ctx_set (fd, this, (uint64_t)(long) fd_ctx);
+                if (ret < 0) {
+                        op_ret = ret;
+                }
+
+                INIT_LIST_HEAD (&fd_ctx->entries);
+        }
+unlock:
+        UNLOCK (&fd->lock);
+out:
+        return ret;
+}
+
+/* {{{ flush */
+
+int
+afr_flush_unwind (call_frame_t *frame, xlator_t *this)
+{
+	afr_local_t *   local = NULL;
+	afr_private_t * priv  = NULL;
+	call_frame_t   *main_frame = NULL;
+
+	local = frame->local;
+	priv  = this->private;
+
+	LOCK (&frame->lock);
+	{
+		if (local->transaction.main_frame)
+			main_frame = local->transaction.main_frame;
+		local->transaction.main_frame = NULL;
+	}
+	UNLOCK (&frame->lock);
+
+	if (main_frame) {
+		AFR_STACK_UNWIND (flush, main_frame,
+                                  local->op_ret, local->op_errno);
+	}
+
+	return 0;
+}
+
+
+int
+afr_flush_wind_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+		      int32_t op_ret, int32_t op_errno)
+{
+        afr_local_t *   local = NULL;
+	afr_private_t * priv  = NULL;
+
+	int call_count  = -1;
+	int child_index = (long) cookie;
+	int need_unwind = 0;
+
+	local = frame->local;
+	priv  = this->private;
+
+	LOCK (&frame->lock);
+	{
+		if (afr_fop_failed (op_ret, op_errno))
+			afr_transaction_fop_failed (frame, this, child_index);
+
+		if (op_ret != -1) {
+			if (local->success_count == 0) {
+				local->op_ret = op_ret;
+			}
+			local->success_count++;
+
+			if (local->success_count == priv->wait_count) {
+				need_unwind = 1;
+			}
+		}
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	if (need_unwind)
+		afr_flush_unwind (frame, this);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0) {
+		local->transaction.resume (frame, this);
+	}
+
+	return 0;
+}
+
+
+int
+afr_flush_wind (call_frame_t *frame, xlator_t *this)
+{
+	afr_local_t *local = NULL;
+	afr_private_t *priv = NULL;
+
+	int i = 0;
+	int call_count = -1;
+
+	local = frame->local;
+	priv = this->private;
+
+	call_count = afr_up_children_count (priv->child_count, local->child_up);
+
+	if (call_count == 0) {
+		local->transaction.resume (frame, this);
+		return 0;
+	}
+
+	local->call_count = call_count;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND_COOKIE (frame, afr_flush_wind_cbk,
+					   (void *) (long) i,
+					   priv->children[i],
+					   priv->children[i]->fops->flush,
+					   local->fd);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	return 0;
+}
+
+
+int
+afr_flush_done (call_frame_t *frame, xlator_t *this)
+{
+	afr_local_t *local = NULL;
+
+	local = frame->local;
+
+	local->transaction.unwind (frame, this);
+
+        AFR_STACK_DESTROY (frame);
+
+	return 0;
+}
+
+
+int
+afr_plain_flush_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+                     int32_t op_ret, int32_t op_errno)
+
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (flush, frame, local->op_ret, local->op_errno);
+
+	return 0;
+}
+
+
+static int
+__no_pre_op_done (xlator_t *this, fd_t *fd)
+{
+        int i      = 0;
+        int op_ret = 1;
+
+        int _ret = 0;
+        uint64_t       ctx;
+        afr_fd_ctx_t * fd_ctx = NULL;
+
+        afr_private_t *priv = NULL;
+
+        priv = this->private;
+
+        LOCK (&fd->lock);
+        {
+                _ret = __fd_ctx_get (fd, this, &ctx);
+
+                if (_ret < 0) {
+                        goto out;
+                }
+
+                fd_ctx = (afr_fd_ctx_t *)(long) ctx;
+
+                for (i = 0; i < priv->child_count; i++) {
+                        if (fd_ctx->pre_op_done[i]) {
+                                op_ret = 0;
+                                break;
+                        }
+                }
+        }
+out:
+        UNLOCK (&fd->lock);
+
+        return op_ret;
+}
+
+
+int
+afr_flush (call_frame_t *frame, xlator_t *this, fd_t *fd)
+{
+	afr_private_t * priv  = NULL;
+	afr_local_t   * local = NULL;
+
+        call_frame_t  * transaction_frame = NULL;
+
+	int ret        = -1;
+
+	int op_ret   = -1;
+	int op_errno = 0;
+
+        int i          = 0;
+        int call_count = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+        call_count = afr_up_children_count (priv->child_count, local->child_up);
+
+        if (__no_pre_op_done (this, fd)) {
+                frame->local = local;
+
+                for (i = 0; i < priv->child_count; i++) {
+                        if (local->child_up[i]) {
+                                STACK_WIND_COOKIE (frame, afr_plain_flush_cbk,
+                                                   (void *) (long) i,
+                                                   priv->children[i],
+                                                   priv->children[i]->fops->flush,
+                                                   fd);
+                                if (!--call_count)
+                                        break;
+                        }
+                }
+        } else {
+                transaction_frame = copy_frame (frame);
+                if (!transaction_frame) {
+                        op_errno = ENOMEM;
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "Out of memory.");
+                        goto out;
+                }
+
+                transaction_frame->local = local;
+
+                local->op = GF_FOP_FLUSH;
+
+                local->transaction.fop    = afr_flush_wind;
+                local->transaction.done   = afr_flush_done;
+                local->transaction.unwind = afr_flush_unwind;
+
+                local->fd                 = fd_ref (fd);
+
+                local->transaction.main_frame = frame;
+                local->transaction.start  = 0;
+                local->transaction.len    = 0;
+
+                afr_transaction (transaction_frame, this, AFR_FLUSH_TRANSACTION);
+        }
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+                if (transaction_frame)
+                        AFR_STACK_DESTROY (transaction_frame);
+
+		AFR_STACK_UNWIND (flush, frame, op_ret, op_errno);
+	}
+
+	return 0;
+}
+
+/* }}} */
+
+
+int
+afr_cleanup_fd_ctx (xlator_t *this, fd_t *fd)
+{
+        uint64_t        ctx = 0;
+        afr_fd_ctx_t    *fd_ctx = NULL;
+        int             ret = 0;
+
+        ret = fd_ctx_get (fd, this, &ctx);
+
+        if (ret < 0)
+                goto out;
+
+        fd_ctx = (afr_fd_ctx_t *)(long) ctx;
+
+        if (fd_ctx) {
+                if (fd_ctx->child_failed)
+                        GF_FREE (fd_ctx->child_failed);
+
+                if (fd_ctx->pre_op_done)
+                        GF_FREE (fd_ctx->pre_op_done);
+
+                if (fd_ctx->opened_on)
+                        GF_FREE (fd_ctx->opened_on);
+
+                GF_FREE (fd_ctx);
+        }
+
+out:
+        return 0;
+}
+
+
+int
+afr_release (xlator_t *this, fd_t *fd)
+{
+        afr_cleanup_fd_ctx (this, fd);
+
+        return 0;
+}
+
+
+/* {{{ fsync */
+
+int
+afr_fsync_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+               int32_t op_ret, int32_t op_errno, struct iatt *prebuf,
+               struct iatt *postbuf)
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+        int child_index = (long) cookie;
+        int read_child  = 0;
+
+	local = frame->local;
+
+        read_child = afr_read_child (this, local->fd->inode);
+
+	LOCK (&frame->lock);
+	{
+                if (child_index == read_child) {
+                        local->read_child_returned = _gf_true;
+                }
+
+		if (op_ret == 0) {
+			local->op_ret = 0;
+
+			if (local->success_count == 0) {
+				local->cont.fsync.prebuf  = *prebuf;
+				local->cont.fsync.postbuf = *postbuf;
+			}
+
+                        if (child_index == read_child) {
+                                local->cont.fsync.prebuf  = *prebuf;
+                                local->cont.fsync.postbuf = *postbuf;
+                        }
+
+			local->success_count++;
+                }
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0) {
+                local->cont.fsync.prebuf.ia_ino  = local->cont.fsync.ino;
+                local->cont.fsync.postbuf.ia_ino = local->cont.fsync.ino;
+
+		AFR_STACK_UNWIND (fsync, frame, local->op_ret, local->op_errno,
+                                  &local->cont.fsync.prebuf,
+                                  &local->cont.fsync.postbuf);
+        }
+
+	return 0;
+}
+
+
+int
+afr_fsync (call_frame_t *frame, xlator_t *this, fd_t *fd,
+	   int32_t datasync)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+        local->fd             = fd_ref (fd);
+        local->cont.fsync.ino = fd->inode->ino;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND_COOKIE (frame, afr_fsync_cbk,
+                                           (void *) (long) i,
+                                           priv->children[i],
+                                           priv->children[i]->fops->fsync,
+                                           fd, datasync);
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (fsync, frame, op_ret, op_errno, NULL, NULL);
+	}
+	return 0;
+}
+
+/* }}} */
+
+/* {{{ fsync */
+
+int32_t
+afr_fsyncdir_cbk (call_frame_t *frame, void *cookie,
+		  xlator_t *this, int32_t op_ret, int32_t op_errno)
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (fsyncdir, frame, local->op_ret,
+                                  local->op_errno);
+
+	return 0;
+}
+
+
+int32_t
+afr_fsyncdir (call_frame_t *frame, xlator_t *this, fd_t *fd,
+	      int32_t datasync)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_fsyncdir_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->fsyncdir,
+				    fd, datasync);
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (fsyncdir, frame, op_ret, op_errno);
+	}
+	return 0;
+}
+
+/* }}} */
+
+/* {{{ xattrop */
+
+int32_t
+afr_xattrop_cbk (call_frame_t *frame, void *cookie,
+		 xlator_t *this, int32_t op_ret, int32_t op_errno,
+		 dict_t *xattr)
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (xattrop, frame, local->op_ret, local->op_errno,
+                                  xattr);
+
+	return 0;
+}
+
+
+int32_t
+afr_xattrop (call_frame_t *frame, xlator_t *this, loc_t *loc,
+	     gf_xattrop_flags_t optype, dict_t *xattr)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_xattrop_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->xattrop,
+				    loc, optype, xattr);
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (xattrop, frame, op_ret, op_errno, NULL);
+	}
+	return 0;
+}
+
+/* }}} */
+
+/* {{{ fxattrop */
+
+int32_t
+afr_fxattrop_cbk (call_frame_t *frame, void *cookie,
+		  xlator_t *this, int32_t op_ret, int32_t op_errno,
+		  dict_t *xattr)
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (fxattrop, frame, local->op_ret, local->op_errno,
+                                  xattr);
+
+	return 0;
+}
+
+
+int32_t
+afr_fxattrop (call_frame_t *frame, xlator_t *this, fd_t *fd,
+	      gf_xattrop_flags_t optype, dict_t *xattr)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_fxattrop_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->fxattrop,
+				    fd, optype, xattr);
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (fxattrop, frame, op_ret, op_errno, NULL);
+	}
+	return 0;
+}
+
+/* }}} */
+
+
+int32_t
+afr_inodelk_cbk (call_frame_t *frame, void *cookie,
+		 xlator_t *this, int32_t op_ret, int32_t op_errno)
+
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (inodelk, frame, local->op_ret,
+                                  local->op_errno);
+
+	return 0;
+}
+
+
+int32_t
+afr_inodelk (call_frame_t *frame, xlator_t *this,
+             const char *volume, loc_t *loc, int32_t cmd, struct flock *flock)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_inodelk_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->inodelk,
+				    volume, loc, cmd, flock);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (inodelk, frame, op_ret, op_errno);
+	}
+	return 0;
+}
+
+
+int32_t
+afr_finodelk_cbk (call_frame_t *frame, void *cookie,
+		  xlator_t *this, int32_t op_ret, int32_t op_errno)
+
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (finodelk, frame, local->op_ret,
+                                  local->op_errno);
+
+	return 0;
+}
+
+
+int32_t
+afr_finodelk (call_frame_t *frame, xlator_t *this,
+              const char *volume, fd_t *fd, int32_t cmd, struct flock *flock)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_finodelk_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->finodelk,
+				    volume, fd, cmd, flock);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (finodelk, frame, op_ret, op_errno);
+	}
+	return 0;
+}
+
+
+int32_t
+afr_entrylk_cbk (call_frame_t *frame, void *cookie,
+		 xlator_t *this, int32_t op_ret, int32_t op_errno)
+
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (entrylk, frame, local->op_ret,
+                                  local->op_errno);
+
+	return 0;
+}
+
+
+int32_t
+afr_entrylk (call_frame_t *frame, xlator_t *this,
+             const char *volume, loc_t *loc,
+	     const char *basename, entrylk_cmd cmd, entrylk_type type)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_entrylk_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->entrylk,
+				    volume, loc, basename, cmd, type);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (entrylk, frame, op_ret, op_errno);
+	}
+	return 0;
+}
+
+
+
+int32_t
+afr_fentrylk_cbk (call_frame_t *frame, void *cookie,
+		 xlator_t *this, int32_t op_ret, int32_t op_errno)
+
+{
+	afr_local_t *local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+
+	LOCK (&frame->lock);
+	{
+		if (op_ret == 0)
+			local->op_ret = 0;
+
+		local->op_errno = op_errno;
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (fentrylk, frame, local->op_ret,
+                                  local->op_errno);
+
+	return 0;
+}
+
+
+int32_t
+afr_fentrylk (call_frame_t *frame, xlator_t *this,
+              const char *volume, fd_t *fd,
+	      const char *basename, entrylk_cmd cmd, entrylk_type type)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local  = NULL;
+
+	int ret = -1;
+
+	int i = 0;
+	int32_t call_count = 0;
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	call_count = local->call_count;
+	frame->local = local;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_fentrylk_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->fentrylk,
+				    volume, fd, basename, cmd, type);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (fentrylk, frame, op_ret, op_errno);
+	}
+	return 0;
+}
+
+int32_t
+afr_statfs_cbk (call_frame_t *frame, void *cookie,
+		xlator_t *this, int32_t op_ret, int32_t op_errno,
+		struct statvfs *statvfs)
+{
+	afr_local_t *local = NULL;
+
+	int call_count = 0;
+
+	LOCK (&frame->lock);
+	{
+		local = frame->local;
+
+		if (op_ret == 0) {
+			local->op_ret   = op_ret;
+
+			if (local->cont.statfs.buf_set) {
+				if (statvfs->f_bavail < local->cont.statfs.buf.f_bavail)
+					local->cont.statfs.buf = *statvfs;
+			} else {
+				local->cont.statfs.buf = *statvfs;
+				local->cont.statfs.buf_set = 1;
+			}
+		}
+
+		if (op_ret == -1)
+			local->op_errno = op_errno;
+
+	}
+	UNLOCK (&frame->lock);
+
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (statfs, frame, local->op_ret, local->op_errno,
+				  &local->cont.statfs.buf);
+
+	return 0;
+}
+
+
+int32_t
+afr_statfs (call_frame_t *frame, xlator_t *this,
+	    loc_t *loc)
+{
+	afr_private_t *  priv        = NULL;
+	int              child_count = 0;
+	afr_local_t   *  local       = NULL;
+	int              i           = 0;
+
+	int ret = -1;
+	int              call_count = 0;
+	int32_t          op_ret      = -1;
+	int32_t          op_errno    = 0;
+
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+	VALIDATE_OR_GOTO (loc, out);
+
+	priv = this->private;
+	child_count = priv->child_count;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+
+	ret = AFR_LOCAL_INIT (local, priv);
+	if (ret < 0) {
+		op_errno = -ret;
+		goto out;
+	}
+
+	frame->local = local;
+	call_count = local->call_count;
+
+	for (i = 0; i < child_count; i++) {
+		if (local->child_up[i]) {
+			STACK_WIND (frame, afr_statfs_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->statfs,
+				    loc);
+			if (!--call_count)
+				break;
+		}
+	}
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (statfs, frame, op_ret, op_errno, NULL);
+	}
+	return 0;
+}
+
+
+int32_t
+afr_lk_unlock_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+		   int32_t op_ret, int32_t op_errno, struct flock *lock)
+{
+	afr_local_t * local = NULL;
+
+	int call_count = -1;
+
+	local = frame->local;
+	call_count = afr_frame_return (frame);
+
+	if (call_count == 0)
+		AFR_STACK_UNWIND (lk, frame, local->op_ret, local->op_errno,
+				  lock);
+
+	return 0;
+}
+
+
+int32_t
+afr_lk_unlock (call_frame_t *frame, xlator_t *this)
+{
+	afr_local_t   * local = NULL;
+	afr_private_t * priv  = NULL;
+
+	int i;
+	int call_count = 0;
+
+	local = frame->local;
+	priv  = this->private;
+
+	call_count = afr_locked_nodes_count (local->cont.lk.locked_nodes,
+					     priv->child_count);
+
+	if (call_count == 0) {
+		AFR_STACK_UNWIND (lk, frame, local->op_ret, local->op_errno,
+				  &local->cont.lk.flock);
+		return 0;
+	}
+
+	local->call_count = call_count;
+
+	local->cont.lk.flock.l_type = F_UNLCK;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if (local->cont.lk.locked_nodes[i]) {
+			STACK_WIND (frame, afr_lk_unlock_cbk,
+				    priv->children[i],
+				    priv->children[i]->fops->lk,
+				    local->fd, F_SETLK,
+				    &local->cont.lk.flock);
+
+			if (!--call_count)
+				break;
+		}
+	}
+
+	return 0;
+}
+
+
+int32_t
+afr_lk_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
+	    int32_t op_ret, int32_t op_errno, struct flock *lock)
+{
+	afr_local_t *local = NULL;
+	afr_private_t *priv = NULL;
+
+	int call_count  = -1;
+	int child_index = -1;
+
+	local = frame->local;
+	priv  = this->private;
+
+	child_index = (long) cookie;
+
+	call_count = --local->call_count;
+
+	if (!child_went_down (op_ret, op_errno) && (op_ret == -1)) {
+		local->op_ret   = -1;
+		local->op_errno = op_errno;
+
+		afr_lk_unlock (frame, this);
+		return 0;
+	}
+
+	if (op_ret == 0) {
+		local->op_ret        = 0;
+		local->op_errno      = 0;
+		local->cont.lk.locked_nodes[child_index] = 1;
+		local->cont.lk.flock = *lock;
+	}
+
+	child_index++;
+
+	if (child_index < priv->child_count) {
+		STACK_WIND_COOKIE (frame, afr_lk_cbk, (void *) (long) child_index,
+				   priv->children[child_index],
+				   priv->children[child_index]->fops->lk,
+				   local->fd, local->cont.lk.cmd,
+				   &local->cont.lk.flock);
+	} else if (local->op_ret == -1) {
+		/* all nodes have gone down */
+
+		AFR_STACK_UNWIND (lk, frame, -1, ENOTCONN, &local->cont.lk.flock);
+	} else {
+		/* locking has succeeded on all nodes that are up */
+
+		AFR_STACK_UNWIND (lk, frame, local->op_ret, local->op_errno,
+                                  &local->cont.lk.flock);
+	}
+
+	return 0;
+}
+
+
+int
+afr_lk (call_frame_t *frame, xlator_t *this,
+	fd_t *fd, int32_t cmd,
+	struct flock *flock)
+{
+	afr_private_t *priv = NULL;
+	afr_local_t *local = NULL;
+
+	int i = 0;
+
+	int32_t op_ret   = -1;
+	int32_t op_errno = 0;
+
+	VALIDATE_OR_GOTO (frame, out);
+	VALIDATE_OR_GOTO (this, out);
+	VALIDATE_OR_GOTO (this->private, out);
+
+	priv = this->private;
+
+	ALLOC_OR_GOTO (local, afr_local_t, out);
+	AFR_LOCAL_INIT (local, priv);
+
+	frame->local  = local;
+
+	local->cont.lk.locked_nodes = GF_CALLOC (priv->child_count,
+					      sizeof (*local->cont.lk.locked_nodes),
+                                              gf_afr_mt_char);
+
+	if (!local->cont.lk.locked_nodes) {
+		gf_log (this->name, GF_LOG_ERROR, "Out of memory");
+		op_errno = ENOMEM;
+		goto out;
+	}
+
+	local->fd            = fd_ref (fd);
+	local->cont.lk.cmd   = cmd;
+	local->cont.lk.flock = *flock;
+
+	STACK_WIND_COOKIE (frame, afr_lk_cbk, (void *) (long) 0,
+			   priv->children[i],
+			   priv->children[i]->fops->lk,
+			   fd, cmd, flock);
+
+	op_ret = 0;
+out:
+	if (op_ret == -1) {
+		AFR_STACK_UNWIND (lk, frame, op_ret, op_errno, NULL);
+	}
+	return 0;
+}
+
+int
+afr_priv_dump (xlator_t *this)
+{
+	afr_private_t *priv = NULL;
+        char  key_prefix[GF_DUMP_MAX_BUF_LEN];
+        char  key[GF_DUMP_MAX_BUF_LEN];
+        int   i = 0;
+
+
+        assert(this);
+	priv = this->private;
+
+        assert(priv);
+        snprintf(key_prefix, GF_DUMP_MAX_BUF_LEN, "%s.%s", this->type, this->name);
+        gf_proc_dump_add_section(key_prefix);
+        gf_proc_dump_build_key(key, key_prefix, "child_count");
+        gf_proc_dump_write(key, "%u", priv->child_count);
+        gf_proc_dump_build_key(key, key_prefix, "read_child_rr");
+        gf_proc_dump_write(key, "%u", priv->read_child_rr);
+	for (i = 0; i < priv->child_count; i++) {
+                gf_proc_dump_build_key(key, key_prefix, "child_up[%d]", i);
+                gf_proc_dump_write(key, "%d", priv->child_up[i]);
+                gf_proc_dump_build_key(key, key_prefix,
+                                        "pending_key[%d]", i);
+                gf_proc_dump_write(key, "%s", priv->pending_key[i]);
+        }
+        gf_proc_dump_build_key(key, key_prefix, "data_self_heal");
+        gf_proc_dump_write(key, "%d", priv->data_self_heal);
+        gf_proc_dump_build_key(key, key_prefix, "metadata_self_heal");
+        gf_proc_dump_write(key, "%d", priv->metadata_self_heal);
+        gf_proc_dump_build_key(key, key_prefix, "entry_self_heal");
+        gf_proc_dump_write(key, "%d", priv->entry_self_heal);
+        gf_proc_dump_build_key(key, key_prefix, "data_change_log");
+        gf_proc_dump_write(key, "%d", priv->data_change_log);
+        gf_proc_dump_build_key(key, key_prefix, "metadata_change_log");
+        gf_proc_dump_write(key, "%d", priv->metadata_change_log);
+        gf_proc_dump_build_key(key, key_prefix, "entry_change_log");
+        gf_proc_dump_write(key, "%d", priv->entry_change_log);
+        gf_proc_dump_build_key(key, key_prefix, "read_child");
+        gf_proc_dump_write(key, "%d", priv->read_child);
+        gf_proc_dump_build_key(key, key_prefix, "favorite_child");
+        gf_proc_dump_write(key, "%u", priv->favorite_child);
+        gf_proc_dump_build_key(key, key_prefix, "data_lock_server_count");
+        gf_proc_dump_write(key, "%u", priv->data_lock_server_count);
+        gf_proc_dump_build_key(key, key_prefix, "metadata_lock_server_count");
+        gf_proc_dump_write(key, "%u", priv->metadata_lock_server_count);
+        gf_proc_dump_build_key(key, key_prefix, "entry_lock_server_count");
+        gf_proc_dump_write(key, "%u", priv->entry_lock_server_count);
+        gf_proc_dump_build_key(key, key_prefix, "wait_count");
+        gf_proc_dump_write(key, "%u", priv->wait_count);
+
+        return 0;
+}
+
+
+/**
+ * find_child_index - find the child's index in the array of subvolumes
+ * @this: AFR
+ * @child: child
+ */
+
+static int
+find_child_index (xlator_t *this, xlator_t *child)
+{
+	afr_private_t *priv = NULL;
+
+	int i = -1;
+
+	priv = this->private;
+
+	for (i = 0; i < priv->child_count; i++) {
+		if ((xlator_t *) child == priv->children[i])
+			break;
+	}
+
+	return i;
+}
+
+int32_t
+afr_notify (xlator_t *this, int32_t event,
+            void *data, ...)
+{
+	afr_private_t *     priv     = NULL;
+	unsigned char *     child_up = NULL;
+
+	int i           = -1;
+	int up_children = 0;
+
+	priv = this->private;
+
+	if (!priv)
+		return 0;
+
+	child_up = priv->child_up;
+
+	switch (event) {
+	case GF_EVENT_CHILD_UP:
+		i = find_child_index (this, data);
+
+		child_up[i] = 1;
+
+                LOCK (&priv->lock);
+                {
+                        priv->up_count++;
+                }
+                UNLOCK (&priv->lock);
+
+		/*
+		   if all the children were down, and one child came up,
+		   send notify to parent
+		*/
+
+		for (i = 0; i < priv->child_count; i++)
+			if (child_up[i])
+				up_children++;
+
+		if (up_children == 1) {
+                        gf_log (this->name, GF_LOG_NORMAL,
+                                "Subvolume '%s' came back up; "
+                                "going online.", ((xlator_t *)data)->name);
+
+			default_notify (this, event, data);
+                }
+
+		break;
+
+	case GF_EVENT_CHILD_DOWN:
+		i = find_child_index (this, data);
+
+		child_up[i] = 0;
+
+                LOCK (&priv->lock);
+                {
+                        priv->down_count++;
+                }
+                UNLOCK (&priv->lock);
+
+		/*
+		   if all children are down, and this was the last to go down,
+		   send notify to parent
+		*/
+
+		for (i = 0; i < priv->child_count; i++)
+			if (child_up[i])
+				up_children++;
+
+		if (up_children == 0) {
+                        gf_log (this->name, GF_LOG_ERROR,
+                                "All subvolumes are down. Going offline "
+                                "until atleast one of them comes back up.");
+
+			default_notify (this, event, data);
+                }
+
+		break;
+
+	default:
+		default_notify (this, event, data);
+	}
+
+	return 0;
+
+}