vfs_glusterfs: Samba VFS module for glusterfs

Implement a Samba VFS plugin for glusterfs based on gluster's gfapi.
This is a "bottom" vfs plugin (not something to be stacked on top of
another module), and translates (most) calls into closest actions
on gfapi.

Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Simo Sorce <idra@samba.org>
Signed-off-by: Anand Avati <avati@redhat.com>

3 files changed, 1522 insertions, 0 deletions

diff --git a/source3/modules/vfs_glusterfs.c b/source3/modules/vfs_glusterfs.c
new file mode 100644
index 0000000000..24e1bdaea7
--- /dev/null
+++ b/source3/modules/vfs_glusterfs.c
@@ -0,0 +1,1493 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   Wrap GlusterFS GFAPI calls in vfs functions.
+
+   Copyright (c) 2013 Anand Avati <avati@redhat.com>
+
+   This program 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.
+
+   This program 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 "includes.h"
+#include "smbd/smbd.h"
+#include <stdio.h>
+#include "api/glfs.h"
+#include "lib/util/dlinklist.h"
+
+#define DEFAULT_VOLFILE_SERVER "localhost"
+
+/*
+  TODO
+  ----
+  Short term:
+  - AIO support
+  - sendfile/recvfile support
+*/
+
+/* Helpers to provide 'integer' fds */
+
+/* This is global. gfapi's FD operations do not
+   require filesystem context.
+*/
+
+static glfs_fd_t **glfd_fd;
+static int glfd_fd_size;
+static int glfd_fd_used;
+
+static int glfd_fd_store(glfs_fd_t *glfd)
+{
+	int i;
+	void *tmp;
+
+	if (glfd_fd_size == glfd_fd_used) {
+		if (glfd_fd_size >= INT_MAX - 1) {
+			errno = ENOMEM;
+			return -1;
+		}
+
+		tmp = talloc_realloc(glfd_fd, glfd_fd, glfs_fd_t *,
+				     glfd_fd_size + 1);
+		if (tmp == NULL) {
+			errno = ENOMEM;
+			return -1;
+		}
+
+		glfd_fd = tmp;
+		glfd_fd[glfd_fd_size] = 0;
+		glfd_fd_size++;
+	}
+
+	for (i = 0; i < glfd_fd_size; i++) {
+		if (glfd_fd[i] == NULL) {
+			break;
+		}
+	}
+	glfd_fd_used++;
+	glfd_fd[i] = glfd;
+	return i;
+}
+
+static glfs_fd_t *glfd_fd_get(int i)
+{
+	if (i < 0 || i >= glfd_fd_size) {
+		return NULL;
+	}
+	return glfd_fd[i];
+}
+
+static glfs_fd_t *glfd_fd_clear(int i)
+{
+	glfs_fd_t *glfd = NULL;
+
+	if (i < 0 || i >= glfd_fd_size) {
+		return NULL;
+	}
+
+	glfd = glfd_fd[i];
+
+	glfd_fd[i] = 0;
+	glfd_fd_used--;
+	return glfd;
+}
+
+/* Helper to convert stat to stat_ex */
+
+static void smb_stat_ex_from_stat(struct stat_ex *dst, const struct stat *src)
+{
+	ZERO_STRUCTP(dst);
+
+	dst->st_ex_dev = src->st_dev;
+	dst->st_ex_ino = src->st_ino;
+	dst->st_ex_mode = src->st_mode;
+	dst->st_ex_nlink = src->st_nlink;
+	dst->st_ex_uid = src->st_uid;
+	dst->st_ex_gid = src->st_gid;
+	dst->st_ex_rdev = src->st_rdev;
+	dst->st_ex_size = src->st_size;
+	dst->st_ex_atime.tv_sec = src->st_atime;
+#ifdef STAT_HAVE_NSEC
+	dst->st_ex_atime.tv_nsec = src->st_atime_nsec;
+#endif
+	dst->st_ex_mtime.tv_sec = src->st_mtime;
+#ifdef STAT_HAVE_NSEC
+	dst->st_ex_mtime.tv_nsec = src->st_mtime_nsec;
+#endif
+	dst->st_ex_ctime.tv_sec = src->st_ctime;
+#ifdef STAT_HAVE_NSEC
+	dst->st_ex_ctime.tv_nsec = src->st_ctime_nsec;
+#endif
+	dst->st_ex_btime.tv_sec = src->st_mtime;
+#ifdef STAT_HAVE_NSEC
+	dst->st_ex_btime.tv_nsec = src->st_mtime_nsec;
+#endif
+	dst->st_ex_blksize = src->st_blksize;
+	dst->st_ex_blocks = src->st_blocks;
+}
+
+/* pre-opened glfs_t */
+
+static struct glfs_preopened {
+	char *volume;
+	glfs_t *fs;
+	int ref;
+	struct glfs_preopened *next, *prev;
+} *glfs_preopened;
+
+
+int glfs_set_preopened(const char *volume, glfs_t *fs)
+{
+	struct glfs_preopened *entry = NULL;
+
+	entry = talloc_zero(NULL, struct glfs_preopened);
+	if (!entry) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	entry->volume = talloc_strdup(entry, volume);
+	if (!entry->volume) {
+		talloc_free(entry);
+		errno = ENOMEM;
+		return -1;
+	}
+
+	entry->fs = fs;
+	entry->ref = 1;
+
+	DLIST_ADD(glfs_preopened, entry);
+
+	return 0;
+}
+
+static glfs_t *glfs_find_preopened(const char *volume)
+{
+	struct glfs_preopened *entry = NULL;
+
+	for (entry = glfs_preopened; entry; entry = entry->next) {
+		if (strcmp(entry->volume, volume) == 0) {
+			entry->ref++;
+			return entry->fs;
+		}
+	}
+
+	return NULL;
+}
+
+static void glfs_clear_preopened(glfs_t *fs)
+{
+	struct glfs_preopened *entry = NULL;
+
+	for (entry = glfs_preopened; entry; entry = entry->next) {
+		if (entry->fs == fs) {
+			if (--entry->ref)
+				return;
+
+			DLIST_REMOVE(glfs_preopened, entry);
+
+			glfs_fini(entry->fs);
+			talloc_free(entry);
+		}
+	}
+}
+
+/* Disk Operations */
+
+static int vfs_gluster_connect(struct vfs_handle_struct *handle,
+			       const char *service,
+			       const char *user)
+{
+	const char *volfile_server;
+	const char *volume;
+	const char *logfile;
+	int loglevel;
+	glfs_t *fs;
+	int ret;
+
+	logfile = lp_parm_const_string(SNUM(handle->conn), "glusterfs",
+				       "logfile", NULL);
+
+	loglevel = lp_parm_int(SNUM(handle->conn), "glusterfs", "loglevel", -1);
+
+	volfile_server = lp_parm_const_string(SNUM(handle->conn), "glusterfs",
+					       "volfile_server", NULL);
+	if (volfile_server == NULL) {
+		volfile_server = DEFAULT_VOLFILE_SERVER;
+	}
+
+	volume = lp_parm_const_string(SNUM(handle->conn), "glusterfs", "volume",
+				      NULL);
+	if (volume == NULL) {
+		volume = service;
+	}
+
+	fs = glfs_find_preopened(volume);
+	if (fs) {
+		goto found;
+	}
+
+	fs = glfs_new(volume);
+	if (fs == NULL) {
+		return -1;
+	}
+
+	ret = glfs_set_volfile_server(fs, "tcp", volfile_server, 0);
+	if (ret < 0) {
+		DEBUG(0, ("Failed to set volfile_server %s\n", volfile_server));
+		glfs_fini(fs);
+		return -1;
+	}
+
+	ret = glfs_set_xlator_option(fs, "*-md-cache", "cache-posix-acl",
+				     "true");
+	if (ret < 0) {
+		DEBUG(0, ("%s: Failed to set xlator options\n", volume));
+		glfs_fini(fs);
+		return -1;
+	}
+
+	ret = glfs_set_logging(fs, logfile, loglevel);
+	if (ret < 0) {
+		DEBUG(0, ("%s: Failed to set logfile %s loglevel %d\n",
+			  volume, logfile, loglevel));
+		glfs_fini(fs);
+		return -1;
+	}
+
+	ret = glfs_init(fs);
+	if (ret < 0) {
+		DEBUG(0, ("%s: Failed to initialize volume (%s)\n",
+			  volume, strerror(errno)));
+		glfs_fini(fs);
+		return -1;
+	}
+
+	ret = glfs_set_preopened(volume, fs);
+	if (ret < 0) {
+		DEBUG(0, ("%s: Failed to register volume (%s)\n",
+			  volume, strerror(errno)));
+		glfs_fini(fs);
+		return -1;
+	}
+found:
+	DEBUG(0, ("%s: Initialized volume from server %s\n",
+		  volume, volfile_server));
+	handle->data = fs;
+	return 0;
+}
+
+static void vfs_gluster_disconnect(struct vfs_handle_struct *handle)
+{
+	glfs_t *fs = NULL;
+
+	fs = handle->data;
+
+	glfs_clear_preopened(fs);
+}
+
+static uint64_t vfs_gluster_disk_free(struct vfs_handle_struct *handle,
+				      const char *path, bool small_query,
+				      uint64_t *bsize_p, uint64_t *dfree_p,
+				      uint64_t *dsize_p)
+{
+	struct statvfs statvfs = { 0, };
+	uint64_t dfree = 0;
+	int ret;
+
+	ret = glfs_statvfs(handle->data, path, &statvfs);
+	if (ret < 0) {
+		return -1;
+	}
+
+	dfree = statvfs.f_bsize * statvfs.f_bavail;
+
+	if (bsize_p != NULL) {
+		*bsize_p = statvfs.f_bsize;
+	}
+	if (dfree_p != NULL) {
+		*dfree_p = dfree;
+	}
+	if (dsize_p != NULL) {
+		*dsize_p = statvfs.f_bsize * statvfs.f_blocks;
+	}
+
+	return dfree;
+}
+
+static int vfs_gluster_get_quota(struct vfs_handle_struct *handle,
+				 enum SMB_QUOTA_TYPE qtype, unid_t id,
+				 SMB_DISK_QUOTA *qt)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+static int
+vfs_gluster_set_quota(struct vfs_handle_struct *handle,
+		      enum SMB_QUOTA_TYPE qtype, unid_t id, SMB_DISK_QUOTA *qt)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+static int vfs_gluster_statvfs(struct vfs_handle_struct *handle,
+			       const char *path,
+			       struct vfs_statvfs_struct *vfs_statvfs)
+{
+	struct statvfs statvfs = { 0, };
+	int ret;
+
+	ret = glfs_statvfs(handle->data, path, &statvfs);
+	if (ret < 0) {
+		DEBUG(0, ("glfs_statvfs(%s) failed: %s\n",
+			  path, strerror(errno)));
+		return -1;
+	}
+
+	ZERO_STRUCTP(vfs_statvfs);
+
+	vfs_statvfs->OptimalTransferSize = statvfs.f_frsize;
+	vfs_statvfs->BlockSize = statvfs.f_bsize;
+	vfs_statvfs->TotalBlocks = statvfs.f_blocks;
+	vfs_statvfs->BlocksAvail = statvfs.f_bfree;
+	vfs_statvfs->UserBlocksAvail = statvfs.f_bavail;
+	vfs_statvfs->TotalFileNodes = statvfs.f_files;
+	vfs_statvfs->FreeFileNodes = statvfs.f_ffree;
+	vfs_statvfs->FsIdentifier = statvfs.f_fsid;
+	vfs_statvfs->FsCapabilities =
+	    FILE_CASE_SENSITIVE_SEARCH | FILE_CASE_PRESERVED_NAMES;
+
+	return ret;
+}
+
+static uint32_t vfs_gluster_fs_capabilities(struct vfs_handle_struct *handle,
+					    enum timestamp_set_resolution *p_ts_res)
+{
+	uint32_t caps = FILE_CASE_SENSITIVE_SEARCH | FILE_CASE_PRESERVED_NAMES;
+
+#ifdef STAT_HAVE_NSEC
+	*p_ts_res = TIMESTAMP_SET_NT_OR_BETTER;
+#endif
+
+	return caps;
+}
+
+static DIR *vfs_gluster_opendir(struct vfs_handle_struct *handle,
+				const char *path, const char *mask,
+				uint32 attributes)
+{
+	glfs_fd_t *fd;
+
+	fd = glfs_opendir(handle->data, path);
+	if (fd == NULL) {
+		DEBUG(0, ("glfs_opendir(%s) failed: %s\n",
+			  path, strerror(errno)));
+	}
+
+	return (DIR *) fd;
+}
+
+static DIR *vfs_gluster_fdopendir(struct vfs_handle_struct *handle,
+				  files_struct *fsp, const char *mask,
+				  uint32 attributes)
+{
+	return (DIR *) glfd_fd_get(fsp->fh->fd);
+}
+
+static int vfs_gluster_closedir(struct vfs_handle_struct *handle, DIR *dirp)
+{
+	return glfs_closedir((void *)dirp);
+}
+
+static struct dirent *vfs_gluster_readdir(struct vfs_handle_struct *handle,
+					  DIR *dirp, SMB_STRUCT_STAT *sbuf)
+{
+	static char direntbuf[512];
+	int ret;
+	struct stat stat;
+	struct dirent *dirent = 0;
+
+	if (sbuf != NULL) {
+		ret = glfs_readdirplus_r((void *)dirp, &stat, (void *)direntbuf,
+					 &dirent);
+	} else {
+		ret = glfs_readdir_r((void *)dirp, (void *)direntbuf, &dirent);
+	}
+
+	if ((ret < 0) || (dirent == NULL)) {
+		return NULL;
+	}
+
+	if (sbuf != NULL) {
+		smb_stat_ex_from_stat(sbuf, &stat);
+	}
+
+	return dirent;
+}
+
+static long vfs_gluster_telldir(struct vfs_handle_struct *handle, DIR *dirp)
+{
+	return glfs_telldir((void *)dirp);
+}
+
+static void vfs_gluster_seekdir(struct vfs_handle_struct *handle, DIR *dirp,
+				long offset)
+{
+	glfs_seekdir((void *)dirp, offset);
+}
+
+static void vfs_gluster_rewinddir(struct vfs_handle_struct *handle, DIR *dirp)
+{
+	glfs_seekdir((void *)dirp, 0);
+}
+
+static void vfs_gluster_init_search_op(struct vfs_handle_struct *handle,
+				       DIR *dirp)
+{
+	return;
+}
+
+static int vfs_gluster_mkdir(struct vfs_handle_struct *handle, const char *path,
+			     mode_t mode)
+{
+	return glfs_mkdir(handle->data, path, mode);
+}
+
+static int vfs_gluster_rmdir(struct vfs_handle_struct *handle, const char *path)
+{
+	return glfs_rmdir(handle->data, path);
+}
+
+static int vfs_gluster_open(struct vfs_handle_struct *handle,
+			    struct smb_filename *smb_fname, files_struct *fsp,
+			    int flags, mode_t mode)
+{
+	glfs_fd_t *glfd;
+
+	if (flags & O_DIRECTORY) {
+		glfd = glfs_opendir(handle->data, smb_fname->base_name);
+	} else if (flags & O_CREAT) {
+		glfd = glfs_creat(handle->data, smb_fname->base_name, flags,
+				  mode);
+	} else {
+		glfd = glfs_open(handle->data, smb_fname->base_name, flags);
+	}
+
+	if (glfd == NULL) {
+		DEBUG(0, ("glfs_{open[dir],creat}(%s) failed: %s\n",
+			  smb_fname->base_name, strerror(errno)));
+		return -1;
+	}
+
+	return glfd_fd_store(glfd);
+}
+
+static int vfs_gluster_close(struct vfs_handle_struct *handle,
+			     files_struct *fsp)
+{
+	return glfs_close(glfd_fd_clear(fsp->fh->fd));
+}
+
+static ssize_t vfs_gluster_read(struct vfs_handle_struct *handle,
+				files_struct *fsp, void *data, size_t n)
+{
+	return glfs_read(glfd_fd_get(fsp->fh->fd), data, n, 0);
+}
+
+static ssize_t vfs_gluster_pread(struct vfs_handle_struct *handle,
+				 files_struct *fsp, void *data, size_t n,
+				 off_t offset)
+{
+	return glfs_pread(glfd_fd_get(fsp->fh->fd), data, n, offset, 0);
+}
+
+static struct tevent_req *vfs_gluster_pread_send(struct vfs_handle_struct
+						 *handle, TALLOC_CTX *mem_ctx,
+						 struct tevent_context *ev,
+						 files_struct *fsp, void *data,
+						 size_t n, off_t offset)
+{
+	errno = ENOTSUP;
+	return NULL;
+}
+
+static ssize_t vfs_gluster_pread_recv(struct tevent_req *req, int *err)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static ssize_t vfs_gluster_write(struct vfs_handle_struct *handle,
+				 files_struct *fsp, const void *data, size_t n)
+{
+	return glfs_write(glfd_fd_get(fsp->fh->fd), data, n, 0);
+}
+
+static ssize_t vfs_gluster_pwrite(struct vfs_handle_struct *handle,
+				  files_struct *fsp, const void *data,
+				  size_t n, off_t offset)
+{
+	return glfs_pwrite(glfd_fd_get(fsp->fh->fd), data, n, offset, 0);
+}
+
+static struct tevent_req *vfs_gluster_pwrite_send(struct vfs_handle_struct
+						  *handle, TALLOC_CTX *mem_ctx,
+						  struct tevent_context *ev,
+						  files_struct *fsp,
+						  const void *data, size_t n,
+						  off_t offset)
+{
+	errno = ENOTSUP;
+	return NULL;
+}
+
+static ssize_t vfs_gluster_pwrite_recv(struct tevent_req *req, int *err)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static off_t vfs_gluster_lseek(struct vfs_handle_struct *handle,
+			       files_struct *fsp, off_t offset, int whence)
+{
+	return glfs_lseek(glfd_fd_get(fsp->fh->fd), offset, whence);
+}
+
+static ssize_t vfs_gluster_sendfile(struct vfs_handle_struct *handle, int tofd,
+				    files_struct *fromfsp,
+				    const DATA_BLOB *hdr,
+				    off_t offset, size_t n)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static ssize_t vfs_gluster_recvfile(struct vfs_handle_struct *handle,
+				    int fromfd, files_struct *tofsp,
+				    off_t offset, size_t n)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static int vfs_gluster_rename(struct vfs_handle_struct *handle,
+			      const struct smb_filename *smb_fname_src,
+			      const struct smb_filename *smb_fname_dst)
+{
+	return glfs_rename(handle->data, smb_fname_src->base_name,
+			   smb_fname_dst->base_name);
+}
+
+static int vfs_gluster_fsync(struct vfs_handle_struct *handle,
+			     files_struct *fsp)
+{
+	return glfs_fsync(glfd_fd_get(fsp->fh->fd));
+}
+
+static struct tevent_req *vfs_gluster_fsync_send(struct vfs_handle_struct
+						 *handle, TALLOC_CTX *mem_ctx,
+						 struct tevent_context *ev,
+						 files_struct *fsp)
+{
+	errno = ENOTSUP;
+	return NULL;
+}
+
+static int vfs_gluster_fsync_recv(struct tevent_req *req, int *err)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static int vfs_gluster_stat(struct vfs_handle_struct *handle,
+			    struct smb_filename *smb_fname)
+{
+	struct stat st;
+	int ret;
+
+	ret = glfs_stat(handle->data, smb_fname->base_name, &st);
+	if (ret == 0) {
+		smb_stat_ex_from_stat(&smb_fname->st, &st);
+	}
+	if (ret < 0 && errno != ENOENT) {
+		DEBUG(0, ("glfs_stat(%s) failed: %s\n",
+			  smb_fname->base_name, strerror(errno)));
+	}
+	return ret;
+}
+
+static int vfs_gluster_fstat(struct vfs_handle_struct *handle,
+			     files_struct *fsp, SMB_STRUCT_STAT *sbuf)
+{
+	struct stat st;
+	int ret;
+
+	ret = glfs_fstat(glfd_fd_get(fsp->fh->fd), &st);
+	if (ret == 0) {
+		smb_stat_ex_from_stat(sbuf, &st);
+	}
+	if (ret < 0) {
+		DEBUG(0, ("glfs_fstat(%d) failed: %s\n",
+			  fsp->fh->fd, strerror(errno)));
+	}
+	return ret;
+}
+
+static int vfs_gluster_lstat(struct vfs_handle_struct *handle,
+			     struct smb_filename *smb_fname)
+{
+	struct stat st;
+	int ret;
+
+	ret = glfs_lstat(handle->data, smb_fname->base_name, &st);
+	if (ret == 0) {
+		smb_stat_ex_from_stat(&smb_fname->st, &st);
+	}
+	if (ret < 0 && errno != ENOENT) {
+		DEBUG(0, ("glfs_lstat(%s) failed: %s\n",
+			  smb_fname->base_name, strerror(errno)));
+	}
+	return ret;
+}
+
+static uint64_t vfs_gluster_get_alloc_size(struct vfs_handle_struct *handle,
+					   files_struct *fsp,
+					   const SMB_STRUCT_STAT *sbuf)
+{
+	return sbuf->st_ex_blocks * 512;
+}
+
+static int vfs_gluster_unlink(struct vfs_handle_struct *handle,
+			      const struct smb_filename *smb_fname)
+{
+	return glfs_unlink(handle->data, smb_fname->base_name);
+}
+
+static int vfs_gluster_chmod(struct vfs_handle_struct *handle,
+			     const char *path, mode_t mode)
+{
+	return glfs_chmod(handle->data, path, mode);
+}
+
+static int vfs_gluster_fchmod(struct vfs_handle_struct *handle,
+			      files_struct *fsp, mode_t mode)
+{
+	return glfs_fchmod(glfd_fd_get(fsp->fh->fd), mode);
+}
+
+static int vfs_gluster_chown(struct vfs_handle_struct *handle,
+			     const char *path, uid_t uid, gid_t gid)
+{
+	return glfs_chown(handle->data, path, uid, gid);
+}
+
+static int vfs_gluster_fchown(struct vfs_handle_struct *handle,
+			      files_struct *fsp, uid_t uid, gid_t gid)
+{
+	return glfs_fchown(glfd_fd_get(fsp->fh->fd), uid, gid);
+}
+
+static int vfs_gluster_lchown(struct vfs_handle_struct *handle,
+			      const char *path, uid_t uid, gid_t gid)
+{
+	return glfs_lchown(handle->data, path, uid, gid);
+}
+
+static int vfs_gluster_chdir(struct vfs_handle_struct *handle, const char *path)
+{
+	return glfs_chdir(handle->data, path);
+}
+
+static char *vfs_gluster_getwd(struct vfs_handle_struct *handle)
+{
+	char *cwd;
+	char *ret;
+
+	cwd = calloc(1, PATH_MAX + 1);
+	if (cwd == NULL) {
+		return NULL;
+	}
+
+	ret = glfs_getcwd(handle->data, cwd, PATH_MAX);
+	if (ret == 0) {
+		free(cwd);
+	}
+	return ret;
+}
+
+static int vfs_gluster_ntimes(struct vfs_handle_struct *handle,
+			      const struct smb_filename *smb_fname,
+			      struct smb_file_time *ft)
+{
+	struct timespec times[2];
+
+	times[0].tv_sec = ft->atime.tv_sec;
+	times[0].tv_nsec = ft->atime.tv_nsec;
+	times[1].tv_sec = ft->mtime.tv_sec;
+	times[1].tv_nsec = ft->mtime.tv_nsec;
+
+	return glfs_utimens(handle->data, smb_fname->base_name, times);
+}
+
+static int vfs_gluster_ftruncate(struct vfs_handle_struct *handle,
+				 files_struct *fsp, off_t offset)
+{
+	return glfs_ftruncate(glfd_fd_get(fsp->fh->fd), offset);
+}
+
+static int vfs_gluster_fallocate(struct vfs_handle_struct *handle,
+				 struct files_struct *fsp,
+				 enum vfs_fallocate_mode mode,
+				 off_t offset, off_t len)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+static char *vfs_gluster_realpath(struct vfs_handle_struct *handle,
+				  const char *path)
+{
+	return glfs_realpath(handle->data, path, 0);
+}
+
+static bool vfs_gluster_lock(struct vfs_handle_struct *handle,
+			     files_struct *fsp, int op, off_t offset,
+			     off_t count, int type)
+{
+	struct flock flock = { 0, };
+	int ret;
+
+	flock.l_type = type;
+	flock.l_whence = SEEK_SET;
+	flock.l_start = offset;
+	flock.l_len = count;
+	flock.l_pid = 0;
+
+	ret = glfs_posix_lock(glfd_fd_get(fsp->fh->fd), op, &flock);
+
+	if (op == F_GETLK) {
+		/* lock query, true if someone else has locked */
+		if ((ret != -1) &&
+		    (flock.l_type != F_UNLCK) &&
+		    (flock.l_pid != 0) && (flock.l_pid != getpid()))
+			return true;
+		/* not me */
+		return false;
+	}
+
+	if (ret == -1) {
+		return false;
+	}
+
+	return true;
+}
+
+static int vfs_gluster_kernel_flock(struct vfs_handle_struct *handle,
+				    files_struct *fsp, uint32 share_mode,
+				    uint32_t access_mask)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+static int vfs_gluster_linux_setlease(struct vfs_handle_struct *handle,
+				      files_struct *fsp, int leasetype)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+static bool vfs_gluster_getlock(struct vfs_handle_struct *handle,
+				files_struct *fsp, off_t *poffset,
+				off_t *pcount, int *ptype, pid_t *ppid)
+{
+	struct flock flock = { 0, };
+	int ret;
+
+	flock.l_type = *ptype;
+	flock.l_whence = SEEK_SET;
+	flock.l_start = *poffset;
+	flock.l_len = *pcount;
+	flock.l_pid = 0;
+
+	ret = glfs_posix_lock(glfd_fd_get(fsp->fh->fd), F_GETLK, &flock);
+
+	if (ret == -1) {
+		return false;
+	}
+
+	*ptype = flock.l_type;
+	*poffset = flock.l_start;
+	*pcount = flock.l_len;
+	*ppid = flock.l_pid;
+
+	return true;
+}
+
+static int vfs_gluster_symlink(struct vfs_handle_struct *handle,
+			       const char *oldpath, const char *newpath)
+{
+	return glfs_symlink(handle->data, oldpath, newpath);
+}
+
+static int vfs_gluster_readlink(struct vfs_handle_struct *handle,
+				const char *path, char *buf, size_t bufsiz)
+{
+	return glfs_readlink(handle->data, path, buf, bufsiz);
+}
+
+static int vfs_gluster_link(struct vfs_handle_struct *handle,
+			    const char *oldpath, const char *newpath)
+{
+	return glfs_link(handle->data, oldpath, newpath);
+}
+
+static int vfs_gluster_mknod(struct vfs_handle_struct *handle, const char *path,
+			     mode_t mode, SMB_DEV_T dev)
+{
+	return glfs_mknod(handle->data, path, mode, dev);
+}
+
+static NTSTATUS vfs_gluster_notify_watch(struct vfs_handle_struct *handle,
+					 struct sys_notify_context *ctx,
+					 const char *path, uint32_t *filter,
+					 uint32_t *subdir_filter,
+					 void (*callback) (struct sys_notify_context *ctx,
+							   void *private_data,
+							   struct notify_event *ev),
+					 void *private_data, void *handle_p)
+{
+	return NT_STATUS_NOT_IMPLEMENTED;
+}
+
+static int vfs_gluster_chflags(struct vfs_handle_struct *handle,
+			       const char *path, unsigned int flags)
+{
+	errno = ENOSYS;
+	return -1;
+}
+
+static int vfs_gluster_get_real_filename(struct vfs_handle_struct *handle,
+					 const char *path, const char *name,
+					 TALLOC_CTX *mem_ctx, char **found_name)
+{
+	int ret;
+	char key_buf[NAME_MAX + 64];
+	char val_buf[NAME_MAX + 1];
+
+	if (strlen(name) >= NAME_MAX) {
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	snprintf(key_buf, NAME_MAX + 64,
+		 "user.glusterfs.get_real_filename:%s", name);
+
+	ret = glfs_getxattr(handle->data, path, key_buf, val_buf, NAME_MAX + 1);
+	if (ret == -1 && errno == ENODATA) {
+		errno = EOPNOTSUPP;
+		return -1;
+	}
+
+	*found_name = talloc_strdup(mem_ctx, val_buf);
+	if (found_name[0] == NULL) {
+		errno = ENOMEM;
+		return -1;
+	}
+	return 0;
+}
+
+static const char *vfs_gluster_connectpath(struct vfs_handle_struct *handle,
+					   const char *filename)
+{
+	return handle->conn->connectpath;
+}
+
+/* EA Operations */
+
+static ssize_t vfs_gluster_getxattr(struct vfs_handle_struct *handle,
+				    const char *path, const char *name,
+				    void *value, size_t size)
+{
+	return glfs_getxattr(handle->data, path, name, value, size);
+}
+
+static ssize_t vfs_gluster_fgetxattr(struct vfs_handle_struct *handle,
+				     files_struct *fsp, const char *name,
+				     void *value, size_t size)
+{
+	return glfs_fgetxattr(glfd_fd_get(fsp->fh->fd), name, value, size);
+}
+
+static ssize_t vfs_gluster_listxattr(struct vfs_handle_struct *handle,
+				     const char *path, char *list, size_t size)
+{
+	return glfs_listxattr(handle->data, path, list, size);
+}
+
+static ssize_t vfs_gluster_flistxattr(struct vfs_handle_struct *handle,
+				      files_struct *fsp, char *list,
+				      size_t size)
+{
+	return glfs_flistxattr(glfd_fd_get(fsp->fh->fd), list, size);
+}
+
+static int vfs_gluster_removexattr(struct vfs_handle_struct *handle,
+				   const char *path, const char *name)
+{
+	return glfs_removexattr(handle->data, path, name);
+}
+
+static int vfs_gluster_fremovexattr(struct vfs_handle_struct *handle,
+				    files_struct *fsp, const char *name)
+{
+	return glfs_fremovexattr(glfd_fd_get(fsp->fh->fd), name);
+}
+
+static int vfs_gluster_setxattr(struct vfs_handle_struct *handle,
+				const char *path, const char *name,
+				const void *value, size_t size, int flags)
+{
+	return glfs_setxattr(handle->data, path, name, value, size, flags);
+}
+
+static int vfs_gluster_fsetxattr(struct vfs_handle_struct *handle,
+				 files_struct *fsp, const char *name,
+				 const void *value, size_t size, int flags)
+{
+	return glfs_fsetxattr(glfd_fd_get(fsp->fh->fd), name, value, size,
+			      flags);
+}
+
+/* AIO Operations */
+
+static bool vfs_gluster_aio_force(struct vfs_handle_struct *handle,
+				  files_struct *fsp)
+{
+	return false;
+}
+
+/* Offline Operations */
+
+static bool vfs_gluster_is_offline(struct vfs_handle_struct *handle,
+				   const struct smb_filename *fname,
+				   SMB_STRUCT_STAT *sbuf)
+{
+	return false;
+}
+
+static int vfs_gluster_set_offline(struct vfs_handle_struct *handle,
+				   const struct smb_filename *fname)
+{
+	errno = ENOTSUP;
+	return -1;
+}
+
+/* Posix ACL Operations */
+
+#define GLUSTER_ACL_VERSION 2
+#define GLUSTER_ACL_READ    0x04
+#define GLUSTER_ACL_WRITE   0x02
+#define GLUSTER_ACL_EXECUTE 0x01
+
+#define GLUSTER_ACL_UNDEFINED_TAG  0x00
+#define GLUSTER_ACL_USER_OBJ       0x01
+#define GLUSTER_ACL_USER           0x02
+#define GLUSTER_ACL_GROUP_OBJ      0x04
+#define GLUSTER_ACL_GROUP          0x08
+#define GLUSTER_ACL_MASK           0x10
+#define GLUSTER_ACL_OTHER          0x20
+
+#define GLUSTER_ACL_UNDEFINED_ID  (-1)
+
+struct gluster_ace {
+	uint16_t tag;
+	uint16_t perm;
+	uint32_t id;
+};
+
+struct gluster_acl_header {
+	uint32_t version;
+	struct gluster_ace entries[];
+};
+
+static SMB_ACL_T gluster_to_smb_acl(const char *buf, size_t xattr_size,
+				    TALLOC_CTX *mem_ctx)
+{
+	int count;
+	size_t size;
+	struct gluster_ace *ace;
+	struct smb_acl_entry *smb_ace;
+	struct gluster_acl_header *hdr;
+	struct smb_acl_t *result;
+	int i;
+	uint16_t tag;
+	uint16_t perm;
+	uint32_t id;
+
+	size = xattr_size;
+
+	if (size < sizeof(*hdr)) {
+		/* ACL should be at least as big as the header */
+		errno = EINVAL;
+		return NULL;
+	}
+
+	size -= sizeof(*hdr);
+
+	if (size % sizeof(*ace)) {
+		/* Size of entries must strictly be a multiple of
+		   size of an ACE
+		*/
+		errno = EINVAL;
+		return NULL;
+	}
+
+	count = size / sizeof(*ace);
+
+	hdr = (void *)buf;
+
+	if (ntohl(hdr->version) != GLUSTER_ACL_VERSION) {
+		DEBUG(0, ("Unknown gluster ACL version: %d\n",
+			  ntohl(hdr->version)));
+		return NULL;
+	}
+
+	result = sys_acl_init(mem_ctx);
+	if (!result) {
+		errno = ENOMEM;
+		return NULL;
+	}
+
+	result->acl = talloc_array(result, struct smb_acl_entry, count);
+	if (!result->acl) {
+		errno = ENOMEM;
+		talloc_free(result);
+		return NULL;
+	}
+
+	result->count = count;
+
+	smb_ace = result->acl;
+	ace = hdr->entries;
+
+	for (i = 0; i < count; i++) {
+		tag = ntohs(ace->tag);
+
+		switch(tag) {
+		case GLUSTER_ACL_USER:
+			smb_ace->a_type = SMB_ACL_USER;
+			break;
+		case GLUSTER_ACL_USER_OBJ:
+			smb_ace->a_type = SMB_ACL_USER_OBJ;
+			break;
+		case GLUSTER_ACL_GROUP:
+			smb_ace->a_type = SMB_ACL_GROUP;
+			break;
+		case GLUSTER_ACL_GROUP_OBJ:
+			smb_ace->a_type = SMB_ACL_GROUP_OBJ;
+			break;
+		case GLUSTER_ACL_OTHER:
+			smb_ace->a_type = SMB_ACL_OTHER;
+			break;
+		case GLUSTER_ACL_MASK:
+			smb_ace->a_type = SMB_ACL_MASK;
+			break;
+		default:
+			DEBUG(0, ("unknown tag type %d\n", (unsigned int) tag));
+			return NULL;
+		}
+
+		id = ntohl(ace->id);
+
+		switch(smb_ace->a_type) {
+		case SMB_ACL_USER:
+			smb_ace->info.user.uid = id;
+			break;
+		case SMB_ACL_GROUP:
+			smb_ace->info.group.gid = id;
+			break;
+		default:
+			break;
+		}
+
+		perm = ntohs(ace->perm);
+
+		smb_ace->a_perm = 0;
+		smb_ace->a_perm |=
+			((perm & GLUSTER_ACL_READ) ? SMB_ACL_READ : 0);
+		smb_ace->a_perm |=
+			((perm & GLUSTER_ACL_WRITE) ? SMB_ACL_WRITE : 0);
+		smb_ace->a_perm |=
+			((perm & GLUSTER_ACL_EXECUTE) ? SMB_ACL_EXECUTE : 0);
+
+		ace++;
+		smb_ace++;
+	}
+
+	return result;
+}
+
+
+static ssize_t smb_to_gluster_acl(SMB_ACL_T theacl, char *buf, size_t len)
+{
+	ssize_t size;
+	struct gluster_ace *ace;
+	struct smb_acl_entry *smb_ace;
+	struct gluster_acl_header *hdr;
+	int i;
+	int count;
+	uint16_t tag;
+	uint16_t perm;
+	uint32_t id;
+
+	count = theacl->count;
+
+	size = sizeof(*hdr) + (count * sizeof(*ace));
+	if (!buf) {
+		return size;
+	}
+
+	if (len < size) {
+		errno = ERANGE;
+		return -1;
+	}
+
+	hdr = (void *)buf;
+	ace = hdr->entries;
+	smb_ace = theacl->acl;
+
+	hdr->version = htonl(GLUSTER_ACL_VERSION);
+
+	for (i = 0; i < count; i++) {
+		switch(smb_ace->a_type) {
+		case SMB_ACL_USER:
+			tag = GLUSTER_ACL_USER;
+			break;
+		case SMB_ACL_USER_OBJ:
+			tag = GLUSTER_ACL_USER_OBJ;
+			break;
+		case SMB_ACL_GROUP:
+			tag = GLUSTER_ACL_GROUP;
+			break;
+		case SMB_ACL_GROUP_OBJ:
+			tag = GLUSTER_ACL_GROUP_OBJ;
+			break;
+		case SMB_ACL_OTHER:
+			tag = GLUSTER_ACL_OTHER;
+			break;
+		case SMB_ACL_MASK:
+			tag = GLUSTER_ACL_MASK;
+			break;
+		default:
+			DEBUG(0, ("Unknown tag value %d\n",
+				  smb_ace->a_type));
+			errno = EINVAL;
+			return -1;
+		}
+
+		ace->tag = ntohs(tag);
+
+		switch(smb_ace->a_type) {
+		case SMB_ACL_USER:
+			id = smb_ace->info.user.uid;
+			break;
+		case SMB_ACL_GROUP:
+			id = smb_ace->info.group.gid;
+			break;
+		default:
+			id = GLUSTER_ACL_UNDEFINED_ID;
+			break;
+		}
+
+		ace->id = ntohl(id);
+
+		ace->perm = 0;
+		ace->perm |=
+			((smb_ace->a_perm & SMB_ACL_READ) ? GLUSTER_ACL_READ : 0);
+		ace->perm |=
+			((smb_ace->a_perm & SMB_ACL_WRITE) ? GLUSTER_ACL_WRITE : 0);
+		ace->perm |=
+			((smb_ace->a_perm & SMB_ACL_EXECUTE) ? GLUSTER_ACL_EXECUTE : 0);
+
+		ace++;
+		smb_ace++;
+	}
+
+	return size;
+}
+
+
+static SMB_ACL_T vfs_gluster_sys_acl_get_file(struct vfs_handle_struct *handle,
+					      const char *path_p,
+					      SMB_ACL_TYPE_T type,
+					      TALLOC_CTX *mem_ctx)
+{
+	struct smb_acl_t *result;
+	char *buf;
+	char *key;
+	ssize_t ret;
+
+	switch (type) {
+	case SMB_ACL_TYPE_ACCESS:
+		key = "system.posix_acl_access";
+		break;
+	case SMB_ACL_TYPE_DEFAULT:
+		key = "system.posix_acl_default";
+		break;
+	default:
+		errno = EINVAL;
+		return NULL;
+	}
+
+	ret = glfs_getxattr(handle->data, path_p, key, 0, 0);
+	if (ret <= 0) {
+		return NULL;
+	}
+
+	buf = alloca(ret);
+	ret = glfs_getxattr(handle->data, path_p, key, buf, ret);
+	if (ret <= 0) {
+		return NULL;
+	}
+
+	result = gluster_to_smb_acl(buf, ret, mem_ctx);
+
+	return result;
+}
+
+static SMB_ACL_T vfs_gluster_sys_acl_get_fd(struct vfs_handle_struct *handle,
+					    struct files_struct *fsp,
+					    TALLOC_CTX *mem_ctx)
+{
+	struct smb_acl_t *result;
+	int ret;
+	char *buf;
+
+	ret = glfs_fgetxattr(glfd_fd_get(fsp->fh->fd),
+			     "system.posix_acl_access", 0, 0);
+	if (ret <= 0) {
+		return NULL;
+	}
+
+	buf = alloca(ret);
+	ret = glfs_fgetxattr(glfd_fd_get(fsp->fh->fd),
+			     "system.posix_acl_access", buf, ret);
+	if (ret <= 0) {
+		return NULL;
+	}
+
+	result = gluster_to_smb_acl(buf, ret, mem_ctx);
+
+	return result;
+}
+
+static int vfs_gluster_sys_acl_set_file(struct vfs_handle_struct *handle,
+					const char *name,
+					SMB_ACL_TYPE_T acltype,
+					SMB_ACL_T theacl)
+{
+	int ret;
+	char *key;
+	char *buf;
+	ssize_t size;
+
+	switch (acltype) {
+	case SMB_ACL_TYPE_ACCESS:
+		key = "system.posix_acl_access";
+		break;
+	case SMB_ACL_TYPE_DEFAULT:
+		key = "system.posix_acl_default";
+		break;
+	default:
+		errno = EINVAL;
+		return -1;
+	}
+
+	size = smb_to_gluster_acl(theacl, 0, 0);
+	buf = alloca(size);
+
+	size = smb_to_gluster_acl(theacl, buf, size);
+	if (size == -1) {
+		return -1;
+	}
+
+	ret = glfs_setxattr(handle->data, name, key, buf, size, 0);
+
+	return ret;
+}
+
+static int vfs_gluster_sys_acl_set_fd(struct vfs_handle_struct *handle,
+				      struct files_struct *fsp,
+				      SMB_ACL_T theacl)
+{
+	int ret;
+	char *key;
+	char *buf;
+	ssize_t size;
+
+	size = smb_to_gluster_acl(theacl, 0, 0);
+	buf = alloca(size);
+
+	size = smb_to_gluster_acl(theacl, buf, size);
+	if (size == -1) {
+		return -1;
+	}
+
+	ret = glfs_fsetxattr(glfd_fd_get(fsp->fh->fd),
+			     "system.posix_acl_access", buf, size, 0);
+	return ret;
+}
+
+static int vfs_gluster_sys_acl_delete_def_file(struct vfs_handle_struct *handle,
+					       const char *path)
+{
+	return glfs_removexattr(handle->data, path, "system.posix_acl_default");
+}
+
+static struct vfs_fn_pointers glusterfs_fns = {
+
+	/* Disk Operations */
+
+	.connect_fn = vfs_gluster_connect,
+	.disconnect_fn = vfs_gluster_disconnect,
+	.disk_free_fn = vfs_gluster_disk_free,
+	.get_quota_fn = vfs_gluster_get_quota,
+	.set_quota_fn = vfs_gluster_set_quota,
+	.statvfs_fn = vfs_gluster_statvfs,
+	.fs_capabilities_fn = vfs_gluster_fs_capabilities,
+
+	.get_dfs_referrals_fn = NULL,
+
+	/* Directory Operations */
+
+	.opendir_fn = vfs_gluster_opendir,
+	.fdopendir_fn = vfs_gluster_fdopendir,
+	.readdir_fn = vfs_gluster_readdir,
+	.seekdir_fn = vfs_gluster_seekdir,
+	.telldir_fn = vfs_gluster_telldir,
+	.rewind_dir_fn = vfs_gluster_rewinddir,
+	.mkdir_fn = vfs_gluster_mkdir,
+	.rmdir_fn = vfs_gluster_rmdir,
+	.closedir_fn = vfs_gluster_closedir,
+	.init_search_op_fn = vfs_gluster_init_search_op,
+
+	/* File Operations */
+
+	.open_fn = vfs_gluster_open,
+	.create_file_fn = NULL,
+	.close_fn = vfs_gluster_close,
+	.read_fn = vfs_gluster_read,
+	.pread_fn = vfs_gluster_pread,
+	.pread_send_fn = vfs_gluster_pread_send,
+	.pread_recv_fn = vfs_gluster_pread_recv,
+	.write_fn = vfs_gluster_write,
+	.pwrite_fn = vfs_gluster_pwrite,
+	.pwrite_send_fn = vfs_gluster_pwrite_send,
+	.pwrite_recv_fn = vfs_gluster_pwrite_recv,
+	.lseek_fn = vfs_gluster_lseek,
+	.sendfile_fn = vfs_gluster_sendfile,
+	.recvfile_fn = vfs_gluster_recvfile,
+	.rename_fn = vfs_gluster_rename,
+	.fsync_fn = vfs_gluster_fsync,
+	.fsync_send_fn = vfs_gluster_fsync_send,
+	.fsync_recv_fn = vfs_gluster_fsync_recv,
+
+	.stat_fn = vfs_gluster_stat,
+	.fstat_fn = vfs_gluster_fstat,
+	.lstat_fn = vfs_gluster_lstat,
+	.get_alloc_size_fn = vfs_gluster_get_alloc_size,
+	.unlink_fn = vfs_gluster_unlink,
+
+	.chmod_fn = vfs_gluster_chmod,
+	.fchmod_fn = vfs_gluster_fchmod,
+	.chown_fn = vfs_gluster_chown,
+	.fchown_fn = vfs_gluster_fchown,
+	.lchown_fn = vfs_gluster_lchown,
+	.chdir_fn = vfs_gluster_chdir,
+	.getwd_fn = vfs_gluster_getwd,
+	.ntimes_fn = vfs_gluster_ntimes,
+	.ftruncate_fn = vfs_gluster_ftruncate,
+	.fallocate_fn = vfs_gluster_fallocate,
+	.lock_fn = vfs_gluster_lock,
+	.kernel_flock_fn = vfs_gluster_kernel_flock,
+	.linux_setlease_fn = vfs_gluster_linux_setlease,
+	.getlock_fn = vfs_gluster_getlock,
+	.symlink_fn = vfs_gluster_symlink,
+	.readlink_fn = vfs_gluster_readlink,
+	.link_fn = vfs_gluster_link,
+	.mknod_fn = vfs_gluster_mknod,
+	.realpath_fn = vfs_gluster_realpath,
+	.notify_watch_fn = vfs_gluster_notify_watch,
+	.chflags_fn = vfs_gluster_chflags,
+	.file_id_create_fn = NULL,
+	.copy_chunk_send_fn = NULL,
+	.copy_chunk_recv_fn = NULL,
+	.streaminfo_fn = NULL,
+	.get_real_filename_fn = vfs_gluster_get_real_filename,
+	.connectpath_fn = vfs_gluster_connectpath,
+
+	.brl_lock_windows_fn = NULL,
+	.brl_unlock_windows_fn = NULL,
+	.brl_cancel_windows_fn = NULL,
+	.strict_lock_fn = NULL,
+	.strict_unlock_fn = NULL,
+	.translate_name_fn = NULL,
+	.fsctl_fn = NULL,
+
+	/* NT ACL Operations */
+	.fget_nt_acl_fn = NULL,
+	.get_nt_acl_fn = NULL,
+	.fset_nt_acl_fn = NULL,
+	.audit_file_fn = NULL,
+
+	/* Posix ACL Operations */
+	.chmod_acl_fn = NULL,	/* passthrough to default */
+	.fchmod_acl_fn = NULL,	/* passthrough to default */
+	.sys_acl_get_file_fn = vfs_gluster_sys_acl_get_file,
+	.sys_acl_get_fd_fn = vfs_gluster_sys_acl_get_fd,
+	.sys_acl_blob_get_file_fn = posix_sys_acl_blob_get_file,
+	.sys_acl_blob_get_fd_fn = posix_sys_acl_blob_get_fd,
+	.sys_acl_set_file_fn = vfs_gluster_sys_acl_set_file,
+	.sys_acl_set_fd_fn = vfs_gluster_sys_acl_set_fd,
+	.sys_acl_delete_def_file_fn = vfs_gluster_sys_acl_delete_def_file,
+
+	/* EA Operations */
+	.getxattr_fn = vfs_gluster_getxattr,
+	.fgetxattr_fn = vfs_gluster_fgetxattr,
+	.listxattr_fn = vfs_gluster_listxattr,
+	.flistxattr_fn = vfs_gluster_flistxattr,
+	.removexattr_fn = vfs_gluster_removexattr,
+	.fremovexattr_fn = vfs_gluster_fremovexattr,
+	.setxattr_fn = vfs_gluster_setxattr,
+	.fsetxattr_fn = vfs_gluster_fsetxattr,
+
+	/* AIO Operations */
+	.aio_force_fn = vfs_gluster_aio_force,
+
+	/* Offline Operations */
+	.is_offline_fn = vfs_gluster_is_offline,
+	.set_offline_fn = vfs_gluster_set_offline,
+
+	/* Durable handle Operations */
+	.durable_cookie_fn = NULL,
+	.durable_disconnect_fn = NULL,
+	.durable_reconnect_fn = NULL,
+};
+
+NTSTATUS vfs_glusterfs_init(void);
+NTSTATUS vfs_glusterfs_init(void)
+{
+	return smb_register_vfs(SMB_VFS_INTERFACE_VERSION,
+				"glusterfs", &glusterfs_fns);
+}
diff --git a/source3/modules/wscript_build b/source3/modules/wscript_build
index 937dbdec15..469b2f365c 100644
--- a/source3/modules/wscript_build
+++ b/source3/modules/wscript_build
@@ -52,6 +52,7 @@ VFS_TIME_AUDIT_SRC = 'vfs_time_audit.c'
 VFS_MEDIA_HARMONY_SRC = 'vfs_media_harmony.c'
 VFS_BTRFS_SRC = 'vfs_btrfs.c'
 VFS_CEPH_SRC = 'vfs_ceph.c'
+VFS_GLUSTERFS_SRC = 'vfs_glusterfs.c'
 
 
 bld.SAMBA3_SUBSYSTEM('NFS4_ACLS',
@@ -522,3 +523,12 @@ bld.SAMBA3_MODULE('vfs_ceph',
                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('vfs_ceph'),
                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('vfs_ceph'),
                  cflags=bld.CONFIG_GET('CCFLAGS_CEPHFS'))
+
+bld.SAMBA3_MODULE('vfs_glusterfs',
+                  subsystem='vfs',
+                  source=VFS_GLUSTERFS_SRC,
+                  deps='samba-util gfapi',
+                  init_function='',
+                  internal_module=bld.SAMBA3_IS_STATIC_MODULE('vfs_glusterfs'),
+                  enabled=bld.SAMBA3_IS_ENABLED_MODULE('vfs_glusterfs'),
+                  allow_undefined_symbols=False)
diff --git a/source3/wscript b/source3/wscript
index dba6cdc869..98a486f4c7 100644
--- a/source3/wscript
+++ b/source3/wscript
@@ -59,6 +59,7 @@ def set_options(opt):
                    help=("Directory under which libcephfs is installed"),
                    action="store", dest='libcephfs_dir', default=None)
 
+    opt.SAMBA3_ADD_OPTION('glusterfs', with_name="enable", without_name="disable", default=True)
 
 
 def configure(conf):
@@ -1709,6 +1710,21 @@ main() {
     if conf.CHECK_HEADERS('cephfs/libcephfs.h', False, False, 'cephfs') and conf.CHECK_LIB('cephfs'):
         conf.DEFINE('HAVE_CEPH', '1')
 
+    if Options.options.with_glusterfs:
+        conf.check_cfg(package='glusterfs-api', args='"glusterfs-api >= 4" --cflags --libs',
+                       msg='Checking for glusterfs-api >= 4', uselib_store="GFAPI")
+        conf.CHECK_HEADERS('api/glfs.h', lib='gfapi')
+        conf.CHECK_LIB('gfapi', shlib=True)
+
+        if conf.CONFIG_SET('HAVE_API_GLFS_H'):
+            conf.DEFINE('HAVE_GLUSTERFS', '1')
+        else:
+            conf.SET_TARGET_TYPE('gfapi', 'EMPTY')
+            conf.undefine('HAVE_GLUSTERFS')
+    else:
+        conf.SET_TARGET_TYPE('gfapi', 'EMPTY')
+        conf.undefine('HAVE_GLUSTERFS')
+
     conf.env.build_regedit = False
     if not Options.options.with_regedit == False:
         conf.PROCESS_SEPARATE_RULE('system_ncurses')
@@ -1797,6 +1813,9 @@ main() {
     if conf.CONFIG_SET("HAVE_CEPH"):
         default_shared_modules.extend(TO_LIST('vfs_ceph'))
 
+    if conf.CONFIG_SET('HAVE_GLUSTERFS'):
+        default_shared_modules.extend(TO_LIST('vfs_glusterfs'))
+
     explicit_shared_modules = TO_LIST(Options.options.shared_modules, delimiter=',')
     explicit_static_modules = TO_LIST(Options.options.static_modules, delimiter=',')