gfapi: API/library for accessing gluster volumes

Change-Id: Ie4cbcf91b58218bebf23cf951c313aceeb29f311
BUG: 839950
Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-on: http://review.gluster.com/3664
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-by: Kaleb KEITHLEY <kkeithle@redhat.com>
Reviewed-by: Bharata B Rao <bharata.rao@gmail.com>

10 files changed, 2860 insertions, 0 deletions

diff --git a/api/Makefile.am b/api/Makefile.am
new file mode 100644
index 00000000000..af437a64d6d
--- /dev/null
+++ b/api/Makefile.am
@@ -0,0 +1 @@
+SUBDIRS = src
diff --git a/api/src/Makefile.am b/api/src/Makefile.am
new file mode 100644
index 00000000000..f5fb9e70b44
--- /dev/null
+++ b/api/src/Makefile.am
@@ -0,0 +1,30 @@
+lib_LTLIBRARIES = libgfapi.la
+noinst_HEADERS = glfs-mem-types.h glfs-internal.h
+libgfapi_HEADERS = glfs.h
+libgfapidir = $(includedir)/glusterfs/api
+
+libgfapi_la_SOURCES = glfs.c glfs-mgmt.c glfs-fops.c glfs-resolve.c
+libgfapi_la_CFLAGS = -fPIC -Wall
+libgfapi_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la
+	$(top_builddir)/rpc/rpc-lib/src/libgfrpc.la \
+	$(top_builddir)/rpc/xdr/src/libgfxdr.la \
+	$(GF_LDADD)
+
+libgfapi_la_CPPFLAGS = -D_FILE_OFFSET_BITS=64 -D__USE_FILE_OFFSET64 -D_GNU_SOURCE \
+	-D$(GF_HOST_OS) $(GF_CFLAGS) \
+	-I$(top_srcdir)/libglusterfs/src \
+	-I$(top_srcdir)/rpc/rpc-lib/src \
+	-I$(top_srcdir)/rpc/xdr/src
+libgfapi_la_LDFLAGS = -shared -nostartfiles
+
+
+xlator_LTLIBRARIES = api.la
+xlatordir = $(libdir)/glusterfs/$(PACKAGE_VERSION)/xlator/mount
+
+api_la_SOURCES = glfs-master.c
+
+api_la_LDFLAGS = -module -avoidversion
+api_la_LIBADD = $(top_builddir)/libglusterfs/src/libglusterfs.la
+
+AM_CFLAGS = -fPIC -D_FILE_OFFSET_BITS=64 -D_GNU_SOURCE -D$(GF_HOST_OS) -Wall \
+	-I$(top_srcdir)/libglusterfs/src $(GF_CFLAGS)
diff --git a/api/src/glfs-fops.c b/api/src/glfs-fops.c
new file mode 100644
index 00000000000..f3fba84e4e7
--- /dev/null
+++ b/api/src/glfs-fops.c
@@ -0,0 +1,829 @@
+/*
+  Copyright (c) 2012 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"
+
+
+struct glfs_fd *
+glfs_open (struct glfs *fs, const char *path, int flags)
+{
+	int              ret = -1;
+	struct glfs_fd  *glfd = NULL;
+	xlator_t        *subvol = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+
+	__glfs_entry_fs (fs);
+
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
+	if (!glfd)
+		goto out;
+
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+	if (ret)
+		goto out;
+
+	if (IA_ISDIR (iatt.ia_type)) {
+		ret = -1;
+		errno = EISDIR;
+		goto out;
+	}
+
+	if (!IA_ISREG (iatt.ia_type)) {
+		ret = -1;
+		errno = EINVAL;
+		goto out;
+	}
+
+	glfd->fd = fd_create (loc.inode, getpid());
+	if (!glfd->fd) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	ret = syncop_open (subvol, &loc, flags, glfd->fd);
+out:
+	loc_wipe (&loc);
+
+	if (ret && glfd) {
+		glfs_fd_destroy (glfd);
+		glfd = NULL;
+	}
+
+	return glfd;
+}
+
+
+int
+glfs_close (struct glfs_fd *glfd)
+{
+	xlator_t  *subvol = NULL;
+	int        ret = -1;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+
+	ret = syncop_flush (subvol, glfd->fd);
+
+	glfs_fd_destroy (glfd);
+
+	return ret;
+}
+
+
+int
+glfs_lstat (struct glfs *fs, const char *path, struct stat *stat)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+
+	__glfs_entry_fs (fs);
+
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+
+	if (ret == 0 && stat)
+		iatt_to_stat (&iatt, stat);
+out:
+	loc_wipe (&loc);
+
+	return ret;
+}
+
+
+int
+glfs_fstat (struct glfs_fd *glfd, struct stat *stat)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+	struct iatt      iatt = {0, };
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	ret = syncop_fstat (subvol, glfd->fd, &iatt);
+
+	if (ret == 0 && stat)
+		iatt_to_stat (&iatt, stat);
+out:
+	return ret;
+}
+
+
+struct glfs_fd *
+glfs_creat (struct glfs *fs, const char *path, int flags, mode_t mode)
+{
+	int              ret = -1;
+	struct glfs_fd  *glfd = NULL;
+	xlator_t        *subvol = NULL;
+	loc_t            loc = {0, };
+	struct iatt      iatt = {0, };
+	uuid_t           gfid;
+	dict_t          *xattr_req = NULL;
+
+	__glfs_entry_fs (fs);
+
+	subvol = glfs_active_subvol (fs);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		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;
+	}
+
+	glfd = GF_CALLOC (1, sizeof (*glfd), glfs_mt_glfs_fd_t);
+	if (!glfd)
+		goto out;
+
+	ret = glfs_resolve (fs, subvol, path, &loc, &iatt);
+	if (ret == -1 && errno != ENOENT)
+		/* Any other type of error is fatal */
+		goto out;
+
+	if (ret == -1 && errno == ENOENT && !loc.parent)
+		/* The parent directory or an ancestor even
+		   higher does not exist
+		*/
+		goto out;
+
+	if (loc.inode) {
+		if (flags & O_EXCL) {
+			ret = -1;
+			errno = EEXIST;
+			goto out;
+		}
+
+		if (IA_ISDIR (iatt.ia_type)) {
+			ret = -1;
+			errno = EISDIR;
+			goto out;
+		}
+
+		if (!IA_ISREG (iatt.ia_type)) {
+			ret = -1;
+			errno = EINVAL;
+			goto out;
+		}
+	}
+
+	if (ret == -1 && errno == ENOENT) {
+		loc.inode = inode_new (loc.parent->table);
+		if (!loc.inode) {
+			ret = -1;
+			errno = ENOMEM;
+			goto out;
+		}
+	}
+
+	glfd->fd = fd_create (loc.inode, getpid());
+	if (!glfd->fd) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	ret = syncop_create (subvol, &loc, flags, mode, glfd->fd, xattr_req);
+out:
+	loc_wipe (&loc);
+
+	if (xattr_req)
+		dict_destroy (xattr_req);
+
+	if (ret && glfd) {
+		glfs_fd_destroy (glfd);
+		glfd = NULL;
+	}
+
+	return glfd;
+}
+
+
+off_t
+glfs_lseek (struct glfs_fd *glfd, off_t offset, int whence)
+{
+	struct stat sb = {0, };
+	int         ret = -1;
+
+	__glfs_entry_fd (glfd);
+
+	switch (whence) {
+	case SEEK_SET:
+		glfd->offset = offset;
+		break;
+	case SEEK_CUR:
+		glfd->offset += offset;
+		break;
+	case SEEK_END:
+		ret = glfs_fstat (glfd, &sb);
+		if (ret) {
+			/* seek cannot fail :O */
+			break;
+		}
+		glfd->offset = sb.st_size + offset;
+		break;
+	}
+
+	return glfd->offset;
+}
+
+
+//////////////
+
+ssize_t
+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;
+	struct iovec   *iov = NULL;
+	int             cnt = 0;
+	struct iobref  *iobref = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+
+	size = iov_length (iovec, iovcnt);
+
+	ret = syncop_readv (subvol, glfd->fd, size, offset,
+			    0, &iov, &cnt, &iobref);
+	if (ret <= 0)
+		return ret;
+
+	size = iov_copy (iovec, iovcnt, iov, cnt); /* FIXME!!! */
+
+	glfd->offset = (offset + size);
+
+	if (iov)
+		GF_FREE (iov);
+	if (iobref)
+		iobref_unref (iobref);
+
+	return size;
+}
+
+
+ssize_t
+glfs_read (struct glfs_fd *glfd, void *buf, size_t count, int flags)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = buf;
+	iov.iov_len = count;
+
+	ret = glfs_preadv (glfd, &iov, 1, glfd->offset, flags);
+
+	return ret;
+}
+
+
+ssize_t
+glfs_pread (struct glfs_fd *glfd, void *buf, size_t count, off_t offset,
+	    int flags)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = buf;
+	iov.iov_len = count;
+
+	ret = glfs_preadv (glfd, &iov, 1, offset, flags);
+
+	return ret;
+}
+
+
+ssize_t
+glfs_readv (struct glfs_fd *glfd, const struct iovec *iov, int count,
+	    int flags)
+{
+	ssize_t      ret = 0;
+
+	ret = glfs_preadv (glfd, iov, count, glfd->offset, flags);
+
+	return ret;
+}
+
+
+struct glfs_io {
+	struct glfs_fd      *glfd;
+	int                  op;
+	off_t                offset;
+	struct iovec        *iov;
+	int                  count;
+	int                  flags;
+	glfs_io_cbk          fn;
+	void                *data;
+};
+
+
+static int
+glfs_io_async_cbk (int ret, call_frame_t *frame, void *data)
+{
+	struct glfs_io  *gio = data;
+
+	gio->fn (gio->glfd, ret, gio->data);
+
+	GF_FREE (gio->iov);
+	GF_FREE (gio);
+
+	return 0;
+}
+
+
+static int
+glfs_io_async_task (void *data)
+{
+	struct glfs_io *gio = 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);
+		break;
+	case GF_FOP_FTRUNCATE:
+		ret = glfs_ftruncate (gio->glfd, gio->offset);
+		break;
+	case GF_FOP_FSYNC:
+		if (gio->flags)
+			ret = glfs_fdatasync (gio->glfd);
+		else
+			ret = glfs_fsync (gio->glfd);
+		break;
+	}
+
+	return (int) ret;
+}
+
+
+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;
+
+	gio = GF_CALLOC (1, sizeof (*gio), glfs_mt_glfs_io_t);
+	if (!gio) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	gio->iov = iov_dup (iovec, count);
+	if (!gio->iov) {
+		GF_FREE (gio);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	gio->op     = GF_FOP_READ;
+	gio->glfd   = glfd;
+	gio->count  = count;
+	gio->offset = offset;
+	gio->flags  = flags;
+	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_read_async (struct glfs_fd *glfd, void *buf, size_t count, int flags,
+		 glfs_io_cbk fn, void *data)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = buf;
+	iov.iov_len = count;
+
+	ret = glfs_preadv_async (glfd, &iov, 1, glfd->offset, flags, fn, data);
+
+	return ret;
+}
+
+
+int
+glfs_pread_async (struct glfs_fd *glfd, void *buf, size_t count, off_t offset,
+		  int flags, glfs_io_cbk fn, void *data)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = buf;
+	iov.iov_len = count;
+
+	ret = glfs_preadv_async (glfd, &iov, 1, offset, flags, fn, data);
+
+	return ret;
+}
+
+
+int
+glfs_readv_async (struct glfs_fd *glfd, const struct iovec *iov, int count,
+		  int flags, glfs_io_cbk fn, void *data)
+{
+	ssize_t      ret = 0;
+
+	ret = glfs_preadv_async (glfd, iov, count, glfd->offset, flags,
+				 fn, data);
+	return ret;
+}
+
+///// writev /////
+
+ssize_t
+glfs_pwritev (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;
+	struct iobref  *iobref = NULL;
+	struct iobuf   *iobuf = NULL;
+	struct iovec    iov = {0, };
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+
+	size = iov_length (iovec, iovcnt);
+
+	iobuf = iobuf_get2 (subvol->ctx->iobuf_pool, size);
+	if (!iobuf) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	iobref = iobref_new ();
+	if (!iobref) {
+		iobuf_unref (iobuf);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	ret = iobref_add (iobref, iobuf);
+	if (ret) {
+		iobuf_unref (iobuf);
+		iobref_unref (iobref);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	iov_unload (iobuf_ptr (iobuf), iovec, iovcnt);  /* FIXME!!! */
+
+	iov.iov_base = iobuf_ptr (iobuf);
+	iov.iov_len = size;
+
+	ret = syncop_writev (subvol, glfd->fd, &iov, 1, offset,
+			     iobref, flags);
+
+	iobuf_unref (iobuf);
+	iobref_unref (iobref);
+
+	if (ret <= 0)
+		return ret;
+
+	glfd->offset = (offset + size);
+
+	return ret;
+}
+
+
+ssize_t
+glfs_write (struct glfs_fd *glfd, const void *buf, size_t count, int flags)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = (void *) buf;
+	iov.iov_len = count;
+
+	ret = glfs_pwritev (glfd, &iov, 1, glfd->offset, flags);
+
+	return ret;
+}
+
+
+
+ssize_t
+glfs_writev (struct glfs_fd *glfd, const struct iovec *iov, int count,
+	     int flags)
+{
+	ssize_t      ret = 0;
+
+	ret = glfs_pwritev (glfd, iov, count, glfd->offset, flags);
+
+	return ret;
+}
+
+
+ssize_t
+glfs_pwrite (struct glfs_fd *glfd, const void *buf, size_t count, off_t offset,
+	     int flags)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = (void *) buf;
+	iov.iov_len = count;
+
+	ret = glfs_pwritev (glfd, &iov, 1, offset, flags);
+
+	return ret;
+}
+
+
+int
+glfs_pwritev_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;
+
+	gio = GF_CALLOC (1, sizeof (*gio), glfs_mt_glfs_io_t);
+	if (!gio) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	gio->iov = iov_dup (iovec, count);
+	if (!gio->iov) {
+		GF_FREE (gio);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	gio->op     = GF_FOP_WRITE;
+	gio->glfd   = glfd;
+	gio->count  = count;
+	gio->offset = offset;
+	gio->flags  = flags;
+	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_write_async (struct glfs_fd *glfd, const void *buf, size_t count, int flags,
+		  glfs_io_cbk fn, void *data)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = (void *) buf;
+	iov.iov_len = count;
+
+	ret = glfs_pwritev_async (glfd, &iov, 1, glfd->offset, flags, fn, data);
+
+	return ret;
+}
+
+
+int
+glfs_pwrite_async (struct glfs_fd *glfd, const void *buf, int count,
+		   off_t offset, int flags, glfs_io_cbk fn, void *data)
+{
+	struct iovec iov = {0, };
+	ssize_t      ret = 0;
+
+	iov.iov_base = (void *) buf;
+	iov.iov_len = count;
+
+	ret = glfs_pwritev_async (glfd, &iov, 1, offset, flags, fn, data);
+
+	return ret;
+}
+
+
+int
+glfs_writev_async (struct glfs_fd *glfd, const struct iovec *iov, int count,
+		   int flags, glfs_io_cbk fn, void *data)
+{
+	ssize_t      ret = 0;
+
+	ret = glfs_pwritev_async (glfd, iov, count, glfd->offset, flags,
+				  fn, data);
+	return ret;
+}
+
+
+int
+glfs_fsync (struct glfs_fd *glfd)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	ret = syncop_fsync (subvol, glfd->fd);
+//	ret = syncop_fsync (subvol, glfd->fd, 0);
+out:
+	return ret;
+}
+
+
+static int
+glfs_fsync_async_common (struct glfs_fd *glfd, glfs_io_cbk fn, void *data,
+			 int dataonly)
+{
+	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_FSYNC;
+	gio->glfd   = glfd;
+	gio->flags  = dataonly;
+	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_fsync_async (struct glfs_fd *glfd, glfs_io_cbk fn, void *data)
+{
+	return glfs_fsync_async_common (glfd, fn, data, 0);
+}
+
+
+int
+glfs_fdatasync (struct glfs_fd *glfd)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	ret = syncop_fsync (subvol, glfd->fd);
+//	ret = syncop_fsync (subvol, glfd->fd, 1);
+out:
+	return ret;
+}
+
+
+int
+glfs_fdatasync_async (struct glfs_fd *glfd, glfs_io_cbk fn, void *data)
+{
+	return glfs_fsync_async_common (glfd, fn, data, 1);
+}
+
+
+int
+glfs_ftruncate (struct glfs_fd *glfd, off_t offset)
+{
+	int              ret = -1;
+	xlator_t        *subvol = NULL;
+
+	__glfs_entry_fd (glfd);
+
+	subvol = glfs_fd_subvol (glfd);
+	if (!subvol) {
+		ret = -1;
+		errno = EIO;
+		goto out;
+	}
+
+	ret = syncop_ftruncate (subvol, glfd->fd, offset);
+out:
+	return ret;
+}
+
+
+int
+glfs_ftruncate_async (struct glfs_fd *glfd, off_t offset,
+		      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_FTRUNCATE;
+	gio->glfd   = glfd;
+	gio->offset = offset;
+	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;
+}
+
diff --git a/api/src/glfs-internal.h b/api/src/glfs-internal.h
new file mode 100644
index 00000000000..967be475cce
--- /dev/null
+++ b/api/src/glfs-internal.h
@@ -0,0 +1,74 @@
+/*
+  Copyright (c) 2012 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_INTERNAL_H
+#define _GLFS_INTERNAL_H
+
+#include "xlator.h"
+
+struct glfs;
+
+typedef int (*glfs_init_cbk) (struct glfs *fs, int ret);
+
+struct glfs {
+	char               *volname;
+
+	glusterfs_ctx_t    *ctx;
+
+	pthread_t           poller;
+
+	glfs_init_cbk       init_cbk;
+	pthread_mutex_t     mutex;
+	pthread_cond_t      cond;
+	int                 init;
+	int                 ret;
+
+	xlator_t           *active_subvol;
+};
+
+struct glfs_fd {
+	off_t     offset;
+	fd_t     *fd;
+};
+
+#define DEFAULT_EVENT_POOL_SIZE           16384
+#define GF_MEMPOOL_COUNT_OF_DICT_T        4096
+#define GF_MEMPOOL_COUNT_OF_DATA_T        (GF_MEMPOOL_COUNT_OF_DICT_T * 4)
+#define GF_MEMPOOL_COUNT_OF_DATA_PAIR_T   (GF_MEMPOOL_COUNT_OF_DICT_T * 4)
+
+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);
+void glfs_first_lookup (xlator_t *subvol);
+
+static inline void
+__glfs_entry_fs (struct glfs *fs)
+{
+	THIS = fs->ctx->master;
+}
+
+
+static inline void
+__glfs_entry_fd (struct glfs_fd *fd)
+{
+	THIS = fd->fd->inode->table->xl->ctx->master;
+}
+
+
+void glfs_fd_destroy (struct glfs_fd *glfd);
+
+xlator_t * glfs_fd_subvol (struct glfs_fd *glfd);
+
+xlator_t * glfs_active_subvol (struct glfs *fs);
+
+#endif /* !_GLFS_INTERNAL_H */
diff --git a/api/src/glfs-master.c b/api/src/glfs-master.c
new file mode 100644
index 00000000000..0806c3077b7
--- /dev/null
+++ b/api/src/glfs-master.c
@@ -0,0 +1,113 @@
+/*
+  Copyright (c) 2012 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 <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+#include <limits.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "xlator.h"
+#include "glusterfs.h"
+#include "glfs-internal.h"
+
+
+int
+glfs_graph_setup (struct glfs *fs, glusterfs_graph_t *graph)
+{
+	if (fs->active_subvol == graph->top)
+		return 0;
+
+	pthread_mutex_lock (&fs->mutex);
+	{
+		fs->active_subvol = graph->top;
+		pthread_cond_broadcast (&fs->cond);
+	}
+	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);
+
+	return 0;
+}
+
+
+int
+notify (xlator_t *this, int event, void *data, ...)
+{
+	glusterfs_graph_t   *graph = NULL;
+	struct glfs	    *fs = NULL;
+
+	graph = data;
+	fs = this->private;
+
+	switch (event) {
+	case GF_EVENT_GRAPH_NEW:
+		gf_log (this->name, GF_LOG_INFO, "New graph %s (%d) coming up",
+			uuid_utoa ((unsigned char *)graph->graph_uuid),
+			graph->id);
+		break;
+	case GF_EVENT_CHILD_UP:
+		glfs_graph_setup (fs, graph);
+		glfs_init_done (fs, 0);
+		break;
+	case GF_EVENT_CHILD_DOWN:
+		glfs_graph_setup (fs, graph);
+		glfs_init_done (fs, 1);
+		break;
+	case GF_EVENT_CHILD_CONNECTING:
+		break;
+	default:
+		gf_log (this->name, GF_LOG_DEBUG,
+			"got notify event %d", event);
+		break;
+	}
+
+	return 0;
+}
+
+
+int
+mem_acct_init (xlator_t *this)
+{
+	return 0;
+}
+
+
+int
+init (xlator_t *this)
+{
+	return 0;
+}
+
+
+void
+fini (xlator_t *this)
+{
+
+}
+
+
+struct xlator_dumpops dumpops = {
+};
+
+
+struct xlator_fops fops = {
+};
+
+
+struct xlator_cbks cbks = {
+};
diff --git a/api/src/glfs-mem-types.h b/api/src/glfs-mem-types.h
new file mode 100644
index 00000000000..dc5da30557a
--- /dev/null
+++ b/api/src/glfs-mem-types.h
@@ -0,0 +1,28 @@
+/*
+  Copyright (c) 2012 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_MEM_TYPES_H
+#define _GLFS_MEM_TYPES_H
+
+#include "mem-types.h"
+
+#define GF_MEM_TYPE_START (gf_common_mt_end + 1)
+
+enum glfs_mem_types_ {
+        glfs_mt_glfs_t,
+        glfs_mt_call_pool_t,
+        glfs_mt_xlator_t,
+	glfs_mt_glfs_fd_t,
+	glfs_mt_glfs_io_t,
+        glfs_mt_end
+
+};
+#endif
+
diff --git a/api/src/glfs-mgmt.c b/api/src/glfs-mgmt.c
new file mode 100644
index 00000000000..526d1ae4d7d
--- /dev/null
+++ b/api/src/glfs-mgmt.c
@@ -0,0 +1,629 @@
+/*
+  Copyright (c) 2012 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 <sys/types.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <pthread.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif /* _CONFIG_H */
+
+#include "glusterfs.h"
+#include "stack.h"
+#include "dict.h"
+#include "event.h"
+#include "defaults.h"
+
+#include "rpc-clnt.h"
+#include "protocol-common.h"
+#include "glusterfs3.h"
+#include "portmap-xdr.h"
+#include "xdr-generic.h"
+
+#include "syncop.h"
+#include "xlator.h"
+
+#include "glfs-internal.h"
+
+
+int glfs_volfile_fetch (struct glfs *fs);
+
+int
+glfs_process_volfp (struct glfs *fs, FILE *fp)
+{
+	glusterfs_graph_t  *graph = NULL;
+	int		    ret = -1;
+	xlator_t	   *trav = NULL;
+	glusterfs_ctx_t	   *ctx = NULL;
+
+	ctx = fs->ctx;
+	graph = glusterfs_graph_construct (fp);
+	if (!graph) {
+		gf_log ("glfs", GF_LOG_ERROR, "failed to construct the graph");
+		goto out;
+	}
+
+	for (trav = graph->first; trav; trav = trav->next) {
+		if (strcmp (trav->type, "mount/fuse") == 0) {
+			gf_log ("glfs", GF_LOG_ERROR,
+				"fuse xlator cannot be specified "
+				"in volume file");
+			goto out;
+		}
+	}
+
+	ret = glusterfs_graph_prepare (graph, ctx);
+	if (ret) {
+		glusterfs_graph_destroy (graph);
+		goto out;
+	}
+
+	ret = glusterfs_graph_activate (graph, ctx);
+
+	if (ret) {
+		glusterfs_graph_destroy (graph);
+		goto out;
+	}
+
+	ret = 0;
+out:
+	if (fp)
+		fclose (fp);
+
+	if (!ctx->active) {
+		ret = -1;
+	}
+
+	return ret;
+}
+
+
+int
+mgmt_cbk_spec (struct rpc_clnt *rpc, void *mydata, void *data)
+{
+	struct glfs *fs = NULL;
+	xlator_t    *this = NULL;
+
+	this = mydata;
+	fs = this->private;
+
+	glfs_volfile_fetch (fs);
+
+	return 0;
+}
+
+
+int
+mgmt_cbk_event (struct rpc_clnt *rpc, void *mydata, void *data)
+{
+	return 0;
+}
+
+
+rpcclnt_cb_actor_t gluster_cbk_actors[] = {
+	[GF_CBK_FETCHSPEC] = {"FETCHSPEC", GF_CBK_FETCHSPEC, mgmt_cbk_spec },
+	[GF_CBK_EVENT_NOTIFY] = {"EVENTNOTIFY", GF_CBK_EVENT_NOTIFY,
+				 mgmt_cbk_event},
+};
+
+
+struct rpcclnt_cb_program mgmt_cbk_prog = {
+	.progname  = "GlusterFS Callback",
+	.prognum   = GLUSTER_CBK_PROGRAM,
+	.progver   = GLUSTER_CBK_VERSION,
+	.actors	   = gluster_cbk_actors,
+	.numactors = GF_CBK_MAXVALUE,
+};
+
+char *clnt_handshake_procs[GF_HNDSK_MAXVALUE] = {
+	[GF_HNDSK_NULL]		= "NULL",
+	[GF_HNDSK_SETVOLUME]	= "SETVOLUME",
+	[GF_HNDSK_GETSPEC]	= "GETSPEC",
+	[GF_HNDSK_PING]		= "PING",
+	[GF_HNDSK_EVENT_NOTIFY] = "EVENTNOTIFY",
+};
+
+rpc_clnt_prog_t clnt_handshake_prog = {
+	.progname  = "GlusterFS Handshake",
+	.prognum   = GLUSTER_HNDSK_PROGRAM,
+	.progver   = GLUSTER_HNDSK_VERSION,
+	.procnames = clnt_handshake_procs,
+};
+
+
+int
+mgmt_submit_request (void *req, call_frame_t *frame,
+		     glusterfs_ctx_t *ctx,
+		     rpc_clnt_prog_t *prog, int procnum,
+		     fop_cbk_fn_t cbkfn, xdrproc_t xdrproc)
+{
+	int			ret	    = -1;
+	int			count	   = 0;
+	struct iovec		iov	    = {0, };
+	struct iobuf		*iobuf = NULL;
+	struct iobref		*iobref = NULL;
+	ssize_t			xdr_size = 0;
+
+	iobref = iobref_new ();
+	if (!iobref) {
+		goto out;
+	}
+
+	if (req) {
+		xdr_size = xdr_sizeof (xdrproc, req);
+
+		iobuf = iobuf_get2 (ctx->iobuf_pool, xdr_size);
+		if (!iobuf) {
+			goto out;
+		};
+
+		iobref_add (iobref, iobuf);
+
+		iov.iov_base = iobuf->ptr;
+		iov.iov_len  = iobuf_pagesize (iobuf);
+
+		/* Create the xdr payload */
+		ret = xdr_serialize_generic (iov, req, xdrproc);
+		if (ret == -1) {
+			gf_log (THIS->name, GF_LOG_WARNING,
+				"failed to create XDR payload");
+			goto out;
+		}
+		iov.iov_len = ret;
+		count = 1;
+	}
+
+	/* Send the msg */
+	ret = rpc_clnt_submit (ctx->mgmt, prog, procnum, cbkfn,
+			       &iov, count,
+			       NULL, 0, iobref, frame, NULL, 0, NULL, 0, NULL);
+
+out:
+	if (iobref)
+		iobref_unref (iobref);
+
+	if (iobuf)
+		iobuf_unref (iobuf);
+	return ret;
+}
+
+
+/* XXX: move these into @ctx */
+static char oldvolfile[131072];
+static int oldvollen = 0;
+
+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 (!oldvollen) {
+		ret = 1; // Has to call INIT for the whole graph
+		goto out;
+	}
+	fwrite (oldvolfile, 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;
+}
+
+
+int
+mgmt_getspec_cbk (struct rpc_req *req, struct iovec *iov, int count,
+		  void *myframe)
+{
+	gf_getspec_rsp		 rsp   = {0,};
+	call_frame_t		*frame = NULL;
+	glusterfs_ctx_t		*ctx = NULL;
+	int			 ret   = 0;
+	ssize_t			 size = 0;
+	FILE			*tmpfp = NULL;
+	struct glfs		*fs = NULL;
+
+	frame = myframe;
+	ctx = frame->this->ctx;
+	fs = ((xlator_t *)ctx->master)->private;
+
+	if (-1 == req->rpc_status) {
+		ret = -1;
+		goto out;
+	}
+
+	ret = xdr_to_generic (*iov, &rsp, (xdrproc_t)xdr_gf_getspec_rsp);
+	if (ret < 0) {
+		gf_log (frame->this->name, GF_LOG_ERROR, "XDR decoding error");
+		ret   = -1;
+		goto out;
+	}
+
+	if (-1 == rsp.op_ret) {
+		gf_log (frame->this->name, GF_LOG_ERROR,
+			"failed to get the 'volume file' from server");
+		ret = -1;
+		goto out;
+	}
+
+	ret = 0;
+	size = rsp.op_ret;
+
+	if (size == oldvollen && (memcmp (oldvolfile, rsp.spec, size) == 0)) {
+		gf_log (frame->this->name, GF_LOG_INFO,
+			"No change in volfile, continuing");
+		goto out;
+	}
+
+	tmpfp = tmpfile ();
+	if (!tmpfp) {
+		ret = -1;
+		goto out;
+	}
+
+	fwrite (rsp.spec, size, 1, tmpfp);
+	fflush (tmpfp);
+	if (ferror (tmpfp)) {
+		ret = -1;
+		goto out;
+	}
+
+	/*  Check if only options have changed. No need to reload the
+	*  volfile if topology hasn't changed.
+	*  glusterfs_volfile_reconfigure returns 3 possible return states
+	*  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
+	*/
+
+	ret = glusterfs_volfile_reconfigure (fs, tmpfp);
+	if (ret == 0) {
+		gf_log ("glusterfsd-mgmt", GF_LOG_DEBUG,
+			"No need to re-load volfile, reconfigure done");
+		oldvollen = size;
+		memcpy (oldvolfile, rsp.spec, size);
+		goto out;
+	}
+
+	if (ret < 0) {
+		gf_log ("glusterfsd-mgmt", GF_LOG_DEBUG,
+			"Reconfigure failed !!");
+		goto out;
+	}
+
+	ret = glfs_process_volfp (fs, tmpfp);
+	/* tmpfp closed */
+	tmpfp = NULL;
+	if (ret)
+		goto out;
+
+	oldvollen = size;
+	memcpy (oldvolfile, rsp.spec, size);
+
+out:
+	STACK_DESTROY (frame->root);
+
+	if (rsp.spec)
+		free (rsp.spec);
+
+	if (ret && ctx && !ctx->active) {
+		/* Do it only for the first time */
+		/* Failed to get the volume file, something wrong,
+		   restart the process */
+		gf_log ("glfs-mgmt", GF_LOG_ERROR,
+			"failed to fetch volume file (key:%s)",
+			ctx->cmd_args.volfile_id);
+	}
+
+	if (tmpfp)
+		fclose (tmpfp);
+
+	return 0;
+}
+
+
+int
+glfs_volfile_fetch (struct glfs *fs)
+{
+	cmd_args_t	 *cmd_args = NULL;
+	gf_getspec_req	  req = {0, };
+	int		  ret = 0;
+	call_frame_t	 *frame = NULL;
+	glusterfs_ctx_t	 *ctx = NULL;
+
+	ctx = fs->ctx;
+	cmd_args = &ctx->cmd_args;
+
+	frame = create_frame (THIS, ctx->pool);
+
+	req.key = cmd_args->volfile_id;
+	req.flags = 0;
+
+	ret = mgmt_submit_request (&req, frame, ctx, &clnt_handshake_prog,
+				   GF_HNDSK_GETSPEC, mgmt_getspec_cbk,
+				   (xdrproc_t)xdr_gf_getspec_req);
+	return ret;
+}
+
+
+static int
+mgmt_rpc_notify (struct rpc_clnt *rpc, void *mydata, rpc_clnt_event_t event,
+		 void *data)
+{
+	xlator_t	*this = NULL;
+	cmd_args_t	*cmd_args = NULL;
+	glusterfs_ctx_t *ctx = NULL;
+	struct glfs	 *fs = NULL;
+	int		 ret = 0;
+
+	this = mydata;
+	ctx = this->ctx;
+	fs = ((xlator_t *)ctx->master)->private;
+	cmd_args = &ctx->cmd_args;
+
+	switch (event) {
+	case RPC_CLNT_DISCONNECT:
+		if (!ctx->active) {
+			cmd_args->max_connect_attempts--;
+			gf_log ("glfs-mgmt", GF_LOG_ERROR,
+				"failed to connect with remote-host: %s",
+				strerror (errno));
+			gf_log ("glfs-mgmt", GF_LOG_INFO,
+				"%d connect attempts left",
+				cmd_args->max_connect_attempts);
+			if (0 >= cmd_args->max_connect_attempts)
+				glfs_init_done (fs, -1);
+				break;
+		}
+		break;
+	case RPC_CLNT_CONNECT:
+		rpc_clnt_set_connected (&((struct rpc_clnt*)ctx->mgmt)->conn);
+
+		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 */
+			gf_log ("glfs-mgmt", GF_LOG_ERROR,
+				"failed to fetch volume file (key:%s)",
+				ctx->cmd_args.volfile_id);
+			glfs_init_done (fs, -1);
+		}
+
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+
+int
+glusterfs_mgmt_notify (int32_t op, void *data, ...)
+{
+	int ret = 0;
+
+	switch (op)
+	{
+		case GF_EN_DEFRAG_STATUS:
+			break;
+
+		default:
+			break;
+	}
+
+	return ret;
+}
+
+
+int
+glfs_mgmt_init (struct glfs *fs)
+{
+	cmd_args_t		*cmd_args = NULL;
+	struct rpc_clnt		*rpc = NULL;
+	dict_t			*options = NULL;
+	int			ret = -1;
+	int			port = GF_DEFAULT_BASE_PORT;
+	char			*host = NULL;
+	glusterfs_ctx_t		*ctx = NULL;
+
+	ctx = fs->ctx;
+	cmd_args = &ctx->cmd_args;
+
+	if (ctx->mgmt)
+		return 0;
+
+	if (cmd_args->volfile_server_port)
+		port = cmd_args->volfile_server_port;
+
+	host = "localhost";
+	if (cmd_args->volfile_server)
+		host = cmd_args->volfile_server;
+
+	ret = rpc_transport_inet_options_build (&options, host, port);
+	if (ret)
+		goto out;
+
+	rpc = rpc_clnt_new (options, THIS->ctx, THIS->name, 8);
+	if (!rpc) {
+		ret = -1;
+		gf_log (THIS->name, GF_LOG_WARNING,
+			"failed to create rpc clnt");
+		goto out;
+	}
+
+	ret = rpc_clnt_register_notify (rpc, mgmt_rpc_notify, THIS);
+	if (ret) {
+		gf_log (THIS->name, GF_LOG_WARNING,
+			"failed to register notify function");
+		goto out;
+	}
+
+	ret = rpcclnt_cbk_program_register (rpc, &mgmt_cbk_prog, THIS);
+	if (ret) {
+		gf_log (THIS->name, GF_LOG_WARNING,
+			"failed to register callback function");
+		goto out;
+	}
+
+	ctx->notify = glusterfs_mgmt_notify;
+
+	/* This value should be set before doing the 'rpc_clnt_start()' as
+	   the notify function uses this variable */
+	ctx->mgmt = rpc;
+
+	ret = rpc_clnt_start (rpc);
+out:
+	return ret;
+}
+
diff --git a/api/src/glfs-resolve.c b/api/src/glfs-resolve.c
new file mode 100644
index 00000000000..c03c4154db0
--- /dev/null
+++ b/api/src/glfs-resolve.c
@@ -0,0 +1,244 @@
+/*
+  Copyright (c) 2012 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 <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+#include <limits.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "glusterfs.h"
+#include "logging.h"
+#include "stack.h"
+#include "event.h"
+#include "glfs-mem-types.h"
+#include "common-utils.h"
+#include "syncop.h"
+#include "call-stub.h"
+
+#include "glfs-internal.h"
+
+
+void
+glfs_first_lookup (xlator_t *subvol)
+{
+	loc_t  loc = {0, };
+	int    ret = -1;
+
+	loc.inode = subvol->itable->root;
+	memset (loc.gfid, 0, 16);
+	loc.gfid[15] = 1;
+	loc.path = "/";
+	loc.name = "";
+
+	ret = syncop_lookup (subvol, &loc, 0, 0, 0, 0);
+
+	gf_log (subvol->name, GF_LOG_DEBUG, "first lookup complete %d", ret);
+
+	return;
+}
+
+
+int
+glfs_loc_touchup (loc_t *loc)
+{
+	char *path = NULL;
+	int   ret = -1;
+	char *bn = NULL;
+
+	ret = inode_path (loc->parent, loc->name, &path);
+
+	loc->path = path;
+
+	if (ret < 0 || !path) {
+		ret = -1;
+		errno = ENOMEM;
+		goto out;
+	}
+
+	bn = strrchr (path, '/');
+	if (bn)
+		bn++;
+	loc->name = bn;
+	ret = 0;
+out:
+	return ret;
+}
+
+
+inode_t *
+glfs_resolve_component (struct glfs *fs, xlator_t *subvol, inode_t *parent,
+			const char *component, struct iatt *iatt)
+{
+	loc_t        loc = {0, };
+	inode_t     *inode = NULL;
+	int          reval = 0;
+	int          ret = -1;
+	int          glret = -1;
+	struct iatt  ciatt = {0, };
+	uuid_t       gfid;
+	dict_t      *xattr_req = NULL;
+
+	loc.name = component;
+
+	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 (loc.inode) {
+		uuid_copy (loc.gfid, loc.inode->gfid);
+		reval = 1;
+	} else {
+		uuid_generate (gfid);
+		loc.inode = inode_new (parent->table);
+	}
+
+	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);
+	if (ret && reval) {
+		inode_unref (loc.inode);
+		loc.inode = inode_new (parent->table);
+		if (!loc.inode)
+			goto out;
+		uuid_generate (gfid);
+		ret = syncop_lookup (subvol, &loc, xattr_req, &ciatt,
+				     NULL, NULL);
+	}
+	if (ret)
+		goto out;
+
+	inode = inode_link (loc.inode, loc.parent, component, &ciatt);
+	if (inode)
+		inode_lookup (inode);
+	if (iatt)
+		*iatt = ciatt;
+out:
+	if (xattr_req)
+		dict_destroy (xattr_req);
+
+	loc_wipe (&loc);
+
+	return inode;
+}
+
+
+int
+glfs_resolve (struct glfs *fs, xlator_t *subvol, const char *origpath,
+	      loc_t *loc, struct iatt *iatt)
+{
+	inode_t    *inode = NULL;
+	inode_t    *parent = NULL;
+	char       *saveptr = NULL;
+	char       *path = NULL;
+	char       *component = NULL;
+	char       *next_component = NULL;
+	int         ret = -1;
+	struct iatt ciatt = {0, };
+
+	path = gf_strdup (origpath);
+	if (!path) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	parent = NULL;
+	inode = inode_ref (subvol->itable->root);
+
+	for (component = strtok_r (path, "/", &saveptr);
+	     component; component = next_component) {
+
+		next_component = strtok_r (NULL, "/", &saveptr);
+
+		if (parent)
+			inode_unref (parent);
+
+		parent = inode;
+
+		inode = glfs_resolve_component (fs, subvol, parent,
+						component, &ciatt);
+		if (!inode)
+			break;
+
+		if (!next_component)
+			break;
+
+		if (!IA_ISDIR (ciatt.ia_type)) {
+			/* next_component exists and this component is
+			   not a directory
+			*/
+			inode_unref (inode);
+			inode = NULL;
+			ret = -1;
+			errno = ENOTDIR;
+			break;
+		}
+	}
+
+	if (parent && next_component)
+		/* resolution failed mid-way */
+		goto out;
+
+	/* At this point, all components up to the last parent directory
+	   have been resolved successfully (@parent). Resolution of basename
+	   might have failed (@inode) if at all.
+	*/
+
+	loc->parent = parent;
+	if (parent) {
+		uuid_copy (loc->pargfid, parent->gfid);
+		loc->name = component;
+	}
+
+	loc->inode = inode;
+	if (inode) {
+		uuid_copy (loc->gfid, inode->gfid);
+		if (iatt)
+			*iatt = ciatt;
+		ret = 0;
+	}
+
+	glfs_loc_touchup (loc);
+out:
+	GF_FREE (path);
+
+	/* do NOT loc_wipe here as only last component might be missing */
+
+	return ret;
+}
+
diff --git a/api/src/glfs.c b/api/src/glfs.c
new file mode 100644
index 00000000000..830efb23d65
--- /dev/null
+++ b/api/src/glfs.c
@@ -0,0 +1,546 @@
+/*
+  Copyright (c) 2012 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.
+*/
+
+
+/*
+  TODO:
+  - 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. ???
+  - syncop_readv to not touch params if args.op_ret < 0.
+  - 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()
+  - modify syncop_fsync() to accept 'dataonly' flag
+  - 0-copy for readv/writev
+*/
+
+#include <unistd.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include <limits.h>
+
+#ifndef _CONFIG_H
+#define _CONFIG_H
+#include "config.h"
+#endif
+
+#include "glusterfs.h"
+#include "logging.h"
+#include "stack.h"
+#include "event.h"
+#include "glfs-mem-types.h"
+#include "common-utils.h"
+#include "syncop.h"
+#include "call-stub.h"
+
+#include "glfs.h"
+#include "glfs-internal.h"
+
+
+static gf_boolean_t
+vol_assigned (cmd_args_t *args)
+{
+	return args->volfile || args->volfile_server;
+}
+
+
+static int
+glusterfs_ctx_defaults_init (glusterfs_ctx_t *ctx)
+{
+	call_pool_t   *pool = NULL;
+	int	       ret = -1;
+	cmd_args_t    *cmd_args = NULL;
+
+	xlator_mem_acct_init (THIS, glfs_mt_end);
+
+	cmd_args = &ctx->cmd_args;
+
+	ctx->process_uuid = generate_glusterfs_ctx_id ();
+	if (!ctx->process_uuid) {
+		goto err;
+	}
+
+	ctx->page_size	= 128 * GF_UNIT_KB;
+
+	ctx->iobuf_pool = iobuf_pool_new ();
+	if (!ctx->iobuf_pool) {
+		goto err;
+	}
+
+	ctx->event_pool = event_pool_new (DEFAULT_EVENT_POOL_SIZE);
+	if (!ctx->event_pool) {
+		goto err;
+	}
+
+	ctx->env = syncenv_new (0);
+	if (!ctx->env) {
+		goto err;
+	}
+
+	pool = GF_CALLOC (1, sizeof (call_pool_t),
+			  glfs_mt_call_pool_t);
+	if (!pool) {
+		goto err;
+	}
+
+	/* frame_mem_pool size 112 * 4k */
+	pool->frame_mem_pool = mem_pool_new (call_frame_t, 4096);
+	if (!pool->frame_mem_pool) {
+		goto err;
+	}
+	/* stack_mem_pool size 256 * 1024 */
+	pool->stack_mem_pool = mem_pool_new (call_stack_t, 1024);
+	if (!pool->stack_mem_pool) {
+		goto err;
+	}
+
+	ctx->stub_mem_pool = mem_pool_new (call_stub_t, 1024);
+	if (!ctx->stub_mem_pool) {
+		goto err;
+	}
+
+	ctx->dict_pool = mem_pool_new (dict_t, GF_MEMPOOL_COUNT_OF_DICT_T);
+	if (!ctx->dict_pool)
+		goto err;
+
+	ctx->dict_pair_pool = mem_pool_new (data_pair_t,
+					    GF_MEMPOOL_COUNT_OF_DATA_PAIR_T);
+	if (!ctx->dict_pair_pool)
+		goto err;
+
+	ctx->dict_data_pool = mem_pool_new (data_t, GF_MEMPOOL_COUNT_OF_DATA_T);
+	if (!ctx->dict_data_pool)
+		goto err;
+
+	INIT_LIST_HEAD (&pool->all_frames);
+	INIT_LIST_HEAD (&ctx->cmd_args.xlator_options);
+	LOCK_INIT (&pool->lock);
+	ctx->pool = pool;
+
+	pthread_mutex_init (&(ctx->lock), NULL);
+
+	ret = 0;
+err:
+	if (ret && pool) {
+		if (pool->frame_mem_pool)
+			mem_pool_destroy (pool->frame_mem_pool);
+		if (pool->stack_mem_pool)
+			mem_pool_destroy (pool->stack_mem_pool);
+		GF_FREE (pool);
+	}
+
+	if (ret && ctx) {
+		if (ctx->stub_mem_pool)
+			mem_pool_destroy (ctx->stub_mem_pool);
+		if (ctx->dict_pool)
+			mem_pool_destroy (ctx->dict_pool);
+		if (ctx->dict_data_pool)
+			mem_pool_destroy (ctx->dict_data_pool);
+		if (ctx->dict_pair_pool)
+			mem_pool_destroy (ctx->dict_pair_pool);
+	}
+
+	return ret;
+}
+
+
+static int
+create_master (struct glfs *fs)
+{
+	int		 ret = 0;
+	xlator_t	*master = NULL;
+
+	master = GF_CALLOC (1, sizeof (*master),
+			    glfs_mt_xlator_t);
+	if (!master)
+		goto err;
+
+	master->name = gf_strdup ("gfapi");
+	if (!master->name)
+		goto err;
+
+	if (xlator_set_type (master, "mount/api") == -1) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"master xlator for %s initialization failed",
+			fs->volname);
+		goto err;
+	}
+
+	master->ctx	 = fs->ctx;
+	master->private	 = fs;
+	master->options	 = get_new_dict ();
+	if (!master->options)
+		goto err;
+
+
+	ret = xlator_init (master);
+	if (ret) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"failed to initialize gfapi translator");
+		goto err;
+	}
+
+	fs->ctx->master = master;
+	THIS = master;
+
+	return 0;
+
+err:
+	if (master) {
+		xlator_destroy (master);
+	}
+
+	return -1;
+}
+
+
+static FILE *
+get_volfp (struct glfs *fs)
+{
+	int	     ret = 0;
+	cmd_args_t  *cmd_args = NULL;
+	FILE	    *specfp = NULL;
+	struct stat  statbuf;
+
+	cmd_args = &fs->ctx->cmd_args;
+
+	ret = lstat (cmd_args->volfile, &statbuf);
+	if (ret == -1) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"%s: %s", cmd_args->volfile, strerror (errno));
+		return NULL;
+	}
+
+	if ((specfp = fopen (cmd_args->volfile, "r")) == NULL) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"volume file %s: %s",
+			cmd_args->volfile,
+			strerror (errno));
+		return NULL;
+	}
+
+	gf_log ("glfs", GF_LOG_DEBUG,
+		"loading volume file %s", cmd_args->volfile);
+
+	return specfp;
+}
+
+
+int
+glfs_volumes_init (struct glfs *fs)
+{
+	FILE		   *fp = NULL;
+	cmd_args_t	   *cmd_args = NULL;
+	int		    ret = 0;
+
+	cmd_args = &fs->ctx->cmd_args;
+
+	if (!vol_assigned (cmd_args))
+		return -1;
+
+	if (cmd_args->volfile_server) {
+		ret = glfs_mgmt_init (fs);
+		goto out;
+	}
+
+	fp = get_volfp (fs);
+
+	if (!fp) {
+		gf_log ("glfs", GF_LOG_ERROR,
+			"Cannot reach volume specification file");
+		ret = -1;
+		goto out;
+	}
+
+	ret = glfs_process_volfp (fs, fp);
+	if (ret)
+		goto out;
+
+out:
+	return ret;
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+
+
+struct glfs *
+glfs_from_glfd (struct glfs_fd *glfd)
+{
+	return 	((xlator_t *)glfd->fd->inode->table->xl->ctx->master)->private;
+}
+
+
+void
+glfs_fd_destroy (struct glfs_fd *glfd)
+{
+	if (!glfd)
+		return;
+	if (glfd->fd)
+		fd_unref (glfd->fd);
+	GF_FREE (glfd);
+}
+
+
+xlator_t *
+glfs_fd_subvol (struct glfs_fd *glfd)
+{
+	xlator_t    *subvol = NULL;
+
+	if (!glfd)
+		return NULL;
+
+	subvol = glfd->fd->inode->table->xl;
+
+	return subvol;
+}
+
+
+xlator_t *
+glfs_active_subvol (struct glfs *fs)
+{
+	xlator_t      *subvol = NULL;
+	inode_table_t *itable = NULL;
+
+	pthread_mutex_lock (&fs->mutex);
+	{
+		while (!fs->init)
+			pthread_cond_wait (&fs->cond, &fs->mutex);
+
+		subvol = fs->active_subvol;
+	}
+	pthread_mutex_unlock (&fs->mutex);
+
+	if (!subvol)
+		return NULL;
+
+	if (!subvol->itable) {
+		itable = inode_table_new (0, subvol);
+		if (!itable) {
+			errno = ENOMEM;
+			return NULL;
+		}
+
+		subvol->itable = itable;
+
+		glfs_first_lookup (subvol);
+	}
+
+	return subvol;
+}
+
+
+static void *
+glfs_poller (void *data)
+{
+	struct glfs  *fs = NULL;
+
+	fs = data;
+
+	event_dispatch (fs->ctx->event_pool);
+
+	return NULL;
+}
+
+
+struct glfs *
+glfs_new (const char *volname)
+{
+	struct glfs     *fs = NULL;
+	int              ret = -1;
+	glusterfs_ctx_t *ctx = NULL;
+
+	/* first globals init, for gf_mem_acct_enable_set () */
+	ret = glusterfs_globals_init ();
+	if (ret)
+		return NULL;
+
+	ctx = glusterfs_ctx_new ();
+	if (!ctx) {
+		return NULL;
+	}
+	THIS->ctx = ctx;
+
+	/* then ctx_defaults_init, for xlator_mem_acct_init(THIS) */
+	ret = glusterfs_ctx_defaults_init (ctx);
+	if (ret)
+		return NULL;
+
+	fs = GF_CALLOC (1, sizeof (*fs), glfs_mt_glfs_t);
+	if (!fs)
+		return NULL;
+	fs->ctx = ctx;
+
+	glfs_set_logging (fs, "/dev/null", 0);
+
+	fs->ctx->cmd_args.volfile_id = gf_strdup (volname);
+
+	fs->volname = gf_strdup (volname);
+
+	pthread_mutex_init (&fs->mutex, NULL);
+	pthread_cond_init (&fs->cond, NULL);
+
+	return fs;
+}
+
+
+int
+glfs_set_volfile (struct glfs *fs, const char *volfile)
+{
+	cmd_args_t  *cmd_args = NULL;
+
+	cmd_args = &fs->ctx->cmd_args;
+
+	if (vol_assigned (cmd_args))
+		return -1;
+
+	cmd_args->volfile = gf_strdup (volfile);
+
+	return 0;
+}
+
+
+int
+glfs_set_volfile_server (struct glfs *fs, const char *transport,
+			 const char *host, int port)
+{
+	cmd_args_t  *cmd_args = NULL;
+
+	cmd_args = &fs->ctx->cmd_args;
+
+	if (vol_assigned (cmd_args))
+		return -1;
+
+	cmd_args->volfile_server = gf_strdup (host);
+	cmd_args->volfile_server_transport = gf_strdup (transport);
+	cmd_args->max_connect_attempts = 2;
+
+	return 0;
+}
+
+
+int
+glfs_set_logging (struct glfs *fs, const char *logfile, int loglevel)
+{
+	int  ret = -1;
+
+	ret = gf_log_init (logfile);
+	if (ret)
+		return ret;
+
+	gf_log_set_loglevel (loglevel);
+
+	return ret;
+}
+
+
+int
+glfs_init_wait (struct glfs *fs)
+{
+	int   ret = -1;
+
+	pthread_mutex_lock (&fs->mutex);
+	{
+		while (!fs->init)
+			pthread_cond_wait (&fs->cond,
+					   &fs->mutex);
+		ret = fs->ret;
+	}
+	pthread_mutex_unlock (&fs->mutex);
+
+	return ret;
+}
+
+
+void
+glfs_init_done (struct glfs *fs, int ret)
+{
+	if (fs->init_cbk) {
+		fs->init_cbk (fs, ret);
+		return;
+	}
+
+	pthread_mutex_lock (&fs->mutex);
+	{
+		fs->init = 1;
+		fs->ret = ret;
+
+		pthread_cond_broadcast (&fs->cond);
+	}
+	pthread_mutex_unlock (&fs->mutex);
+}
+
+
+int
+glfs_init_common (struct glfs *fs)
+{
+	int  ret = -1;
+
+	ret = create_master (fs);
+	if (ret)
+		return ret;
+
+	ret = pthread_create (&fs->poller, NULL, glfs_poller, fs);
+	if (ret)
+		return ret;
+
+	ret = glfs_volumes_init (fs);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
+
+int
+glfs_init_async (struct glfs *fs, glfs_init_cbk cbk)
+{
+	int  ret = -1;
+
+	fs->init_cbk = cbk;
+
+	ret = glfs_init_common (fs);
+
+	return ret;
+}
+
+
+int
+glfs_init (struct glfs *fs)
+{
+	int  ret = -1;
+
+	ret = glfs_init_common (fs);
+	if (ret)
+		return ret;
+
+	ret = glfs_init_wait (fs);
+
+	return ret;
+}
+
+
+int
+glfs_fini (struct glfs *fs)
+{
+	int  ret = -1;
+
+	return ret;
+}
diff --git a/api/src/glfs.h b/api/src/glfs.h
new file mode 100644
index 00000000000..14d41356a02
--- /dev/null
+++ b/api/src/glfs.h
@@ -0,0 +1,366 @@
+/*
+  Copyright (c) 2012 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_H
+#define _GLFS_H
+
+/*
+  Enforce the following flags as libgfapi is built
+  with them, and we want programs linking against them to also
+  be built with these flags. This is necessary as it affects
+  some of the structures defined in libc headers (like struct stat)
+  and those definitions need to be consistently compiled in
+  both the library and the application.
+*/
+
+#ifndef _FILE_OFFSET_BITS
+#define _FILE_OFFSET_BITS 64
+#endif
+
+#ifndef __USE_FILE_OFFSET64
+#define __USE_FILE_OFFSET64
+#endif
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/uio.h>
+#include <unistd.h>
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+/* The filesystem object. One object per 'virtual mount' */
+struct glfs;
+typedef struct glfs glfs_t;
+
+
+/*
+  SYNOPSIS
+
+  glfs_new: Create a new 'virtual mount' object.
+
+  DESCRIPTION
+
+  This is most likely the very first function you will use. This function
+  will create a new glfs_t (virtual mount) object in memory.
+
+  On this newly created glfs_t, you need to be either set a volfile path
+  (glfs_set_volfile) or a volfile server (glfs_set_volfile_server).
+
+  The glfs_t object needs to be initialized with glfs_init() before you
+  can start issuing file operations on it.
+
+  PARAMETERS
+
+  @volname: Name of the volume. This identifies the server-side volume and
+            the fetched volfile (equivalent of --volfile-id command line
+	    parameter to glusterfsd). When used with glfs_set_volfile() the
+	    @volname has no effect (except for appearing in log messages).
+
+  RETURN VALUES
+
+  NULL   : Out of memory condition.
+  Others : Pointer to the newly created glfs_t virtual mount object.
+
+*/
+
+glfs_t *glfs_new (const char *volname);
+
+
+/*
+  SYNOPSIS
+
+  glfs_set_volfile: Specify the path to the volume specification file.
+
+  DESCRIPTION
+
+  If you are using a static volume specification file (without dynamic
+  volume management abilities from the CLI), then specify the path to
+  the volume specification file.
+
+  This is incompatible with glfs_set_volfile_server().
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be configured with the volume
+       specification file.
+
+  @volfile: Path to the locally available volume specification file.
+
+  RETURN VALUES
+
+   0 : Success.
+  -1 : Failure. @errno will be set with the type of failure.
+
+*/
+
+int glfs_set_volfile (glfs_t *fs, const char *volfile);
+
+
+/*
+  SYNOPSIS
+
+  glfs_set_volfile_server: Specify the address of management server.
+
+  DESCRIPTION
+
+  This function specifies the address of the management server (glusterd)
+  to connect, and establish the volume configuration. The @volname
+  parameter passed to glfs_new() is the volume which will be virtually
+  mounted as the glfs_t object. All operations performed by the CLI at
+  the management server will automatically be reflected in the 'virtual
+  mount' object as it maintains a connection to glusterd and polls on
+  configuration change notifications.
+
+  This is incompatible with glfs_set_volfile().
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be configured with the volume
+       specification file.
+
+  @transport: String specifying the transport used to connect to the
+              management daemon. Specifying NULL will result in the usage
+	      of the default (socket) transport type. Permitted values
+	      are those what you specify as transport-type in a volume
+	      specification file (e.g "socket", "rdma", "unix".)
+
+  @host: String specifying the address of where to find the management
+         daemon. Depending on the transport type this would either be
+	 an FQDN (e.g: "storage01.company.com"), ASCII encoded IP
+	 address "192.168.22.1", or a UNIX domain socket path (e.g
+	 "/tmp/glusterd.socket".)
+
+  @port: The TCP port number where gluster management daemon is listening.
+         Specifying 0 uses the default port number GF_DEFAULT_BASE_PORT.
+	 This parameter is unused if you are using a UNIX domain socket.
+
+  RETURN VALUES
+
+   0 : Success.
+  -1 : Failure. @errno will be set with the type of failure.
+
+*/
+
+int glfs_set_volfile_server (glfs_t *fs, const char *transport,
+			     const char *host, int port);
+
+
+/*
+  SYNOPSIS
+
+  glfs_set_logging: Specify logging parameters.
+
+  DESCRIPTION
+
+  This function specifies logging parameters for the virtual mount.
+  Default log file is /dev/null.
+
+  PARAMETERS
+
+  @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.)
+
+  @loglevel: Numerical value specifying the degree of verbosity. Higher the
+             value, more verbose the logging.
+
+  RETURN VALUES
+
+   0 : Success.
+  -1 : Failure. @errno will be set with the type of failure.
+
+*/
+
+int glfs_set_logging (glfs_t *fs, const char *logfile, int loglevel);
+
+
+/*
+  SYNOPSIS
+
+  glfs_init: Initialize the 'virtual mount'
+
+  DESCRIPTION
+
+  This function initializes the glfs_t object. This consists of many steps:
+  - Spawn a poll-loop thread.
+  - Establish connection to management daemon and receive volume specification.
+  - Construct translator graph and initialize graph.
+  - Wait for initialization (connecting to all bricks) to complete.
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be initialized.
+
+  RETURN VALUES
+
+   0 : Success.
+  -1 : Failure. @errno will be set with the type of failure.
+
+*/
+
+int glfs_init (glfs_t *fs);
+
+
+int glfs_fini (glfs_t *fs);
+
+/*
+ * FILE OPERATION
+ *
+ * What follows are filesystem operations performed on the
+ * 'virtual mount'. The calls here are kept as close to
+ * the POSIX system calls as possible.
+ *
+ * Notes:
+ *
+ * - All paths specified, even if absolute, are relative to the
+ *   root of the virtual mount and not the system root (/).
+ *
+ */
+
+/* The file descriptor object. One per open file/directory. */
+
+struct glfs_fd;
+typedef struct glfs_fd glfs_fd_t;
+
+
+/*
+  SYNOPSIS
+
+  glfs_open: Open a file.
+
+  DESCRIPTION
+
+  This function opens a file on a virtual mount.
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be initialized.
+
+  @path: Path of the file within the virtual mount.
+
+  @flags: Open flags. See open(2). O_CREAT is not supported.
+          Use glfs_creat() for creating files.
+
+  RETURN VALUES
+
+  NULL   : Failure. @errno will be set with the type of failure.
+  Others : Pointer to the opened glfs_fd_t.
+
+ */
+
+glfs_fd_t *glfs_open (glfs_t *fs, const char *path, int flags);
+
+
+/*
+  SYNOPSIS
+
+  glfs_creat: Create a file.
+
+  DESCRIPTION
+
+  This function opens a file on a virtual mount.
+
+  PARAMETERS
+
+  @fs: The 'virtual mount' object to be initialized.
+
+  @path: Path of the file within the virtual mount.
+
+  @mode: Permission of the file to be created.
+
+  @flags: Create flags. See open(2). O_EXCL is supported.
+
+  RETURN VALUES
+
+  NULL   : Failure. @errno will be set with the type of failure.
+  Others : Pointer to the opened glfs_fd_t.
+
+ */
+
+glfs_fd_t *glfs_creat (glfs_t *fs, const char *path, int flags,
+		       mode_t mode);
+
+int glfs_close (glfs_fd_t *fd);
+
+glfs_t *glfs_from_glfd (glfs_fd_t *fd);
+
+typedef void (*glfs_io_cbk) (glfs_fd_t *fd, ssize_t ret, void *data);
+
+// glfs_{read,write}[_async]
+
+ssize_t glfs_read (glfs_fd_t *fd, void *buf, size_t count, int flags);
+ssize_t glfs_write (glfs_fd_t *fd, const void *buf, size_t count, int flags);
+int glfs_read_async (glfs_fd_t *fd, void *buf, size_t count, int flags,
+		     glfs_io_cbk fn, void *data);
+int glfs_write_async (glfs_fd_t *fd, const void *buf, size_t count, int flags,
+		      glfs_io_cbk fn, void *data);
+
+// glfs_{read,write}v[_async]
+
+ssize_t glfs_readv (glfs_fd_t *fd, const struct iovec *iov, int iovcnt,
+		    int flags);
+ssize_t glfs_writev (glfs_fd_t *fd, const struct iovec *iov, int iovcnt,
+		     int flags);
+int glfs_readv_async (glfs_fd_t *fd, const struct iovec *iov, int count,
+		      int flags, glfs_io_cbk fn, void *data);
+int glfs_writev_async (glfs_fd_t *fd, const struct iovec *iov, int count,
+		       int flags, glfs_io_cbk fn, void *data);
+
+// glfs_p{read,write}[_async]
+
+ssize_t glfs_pread (glfs_fd_t *fd, void *buf, size_t count, off_t offset,
+		    int flags);
+ssize_t glfs_pwrite (glfs_fd_t *fd, const void *buf, size_t count,
+		     off_t offset, int flags);
+int glfs_pread_async (glfs_fd_t *fd, void *buf, size_t count, off_t offset,
+		      int flags, glfs_io_cbk fn, void *data);
+int glfs_pwrite_async (glfs_fd_t *fd, const void *buf, int count, off_t offset,
+		       int flags, glfs_io_cbk fn, void *data);
+
+// glfs_p{read,write}v[_async]
+
+ssize_t glfs_preadv (glfs_fd_t *fd, const struct iovec *iov, int iovcnt,
+		     off_t offset, int flags);
+ssize_t glfs_pwritev (glfs_fd_t *fd, const struct iovec *iov, int iovcnt,
+		      off_t offset, int flags);
+int glfs_preadv_async (glfs_fd_t *fd, const struct iovec *iov, int count,
+		       off_t offset, int flags, glfs_io_cbk fn, void *data);
+int glfs_pwritev_async (glfs_fd_t *fd, const struct iovec *iov, int count,
+			off_t offset, int flags, glfs_io_cbk fn, void *data);
+
+
+off_t glfs_lseek (glfs_fd_t *fd, off_t offset, int whence);
+
+int glfs_truncate (glfs_t *fs, const char *path, off_t length);
+
+int glfs_ftruncate (glfs_fd_t *fd, off_t length);
+int glfs_ftruncate_async (glfs_fd_t *fd, off_t length, glfs_io_cbk fn,
+			  void *data);
+
+int glfs_lstat (glfs_t *fs, const char *path, struct stat *buf);
+int glfs_fstat (glfs_fd_t *fd, struct stat *buf);
+
+int glfs_fsync (glfs_fd_t *fd);
+int glfs_fsync_async (glfs_fd_t *fd, glfs_io_cbk fn, void *data);
+
+int glfs_fdatasync (glfs_fd_t *fd);
+int glfs_fdatasync_async (glfs_fd_t *fd, glfs_io_cbk fn, void *data);
+
+__END_DECLS
+
+#endif /* !_GLFS_H */