2 * Module to make use of awesome Btrfs features
4 * Copyright (C) David Disseldorp 2011-2013
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
21 #include "system/filesys.h"
22 #include <linux/ioctl.h>
24 #include <sys/ioctl.h>
29 #include "smbd/smbd.h"
30 #include "smbd/globals.h"
31 #include "librpc/gen_ndr/smbXsrv.h"
32 #include "librpc/gen_ndr/ioctl.h"
33 #include "lib/util/tevent_ntstatus.h"
34 #include "offload_token.h"
36 static uint32_t btrfs_fs_capabilities(struct vfs_handle_struct *handle,
37 enum timestamp_set_resolution *_ts_res)
39 uint32_t fs_capabilities;
40 enum timestamp_set_resolution ts_res;
42 /* inherit default capabilities, expose compression support */
43 fs_capabilities = SMB_VFS_NEXT_FS_CAPABILITIES(handle, &ts_res);
44 fs_capabilities |= (FILE_FILE_COMPRESSION
45 | FILE_SUPPORTS_BLOCK_REFCOUNTING);
48 return fs_capabilities;
51 #define SHADOW_COPY_PREFIX "@GMT-" /* vfs_shadow_copy format */
52 #define SHADOW_COPY_PATH_FORMAT "@GMT-%Y.%m.%d-%H.%M.%S"
54 #define BTRFS_SUBVOL_RDONLY (1ULL << 1)
55 #define BTRFS_SUBVOL_NAME_MAX 4039
56 #define BTRFS_PATH_NAME_MAX 4087
57 struct btrfs_ioctl_vol_args_v2 {
62 char name[BTRFS_SUBVOL_NAME_MAX + 1];
64 struct btrfs_ioctl_vol_args {
66 char name[BTRFS_PATH_NAME_MAX + 1];
69 struct btrfs_ioctl_clone_range_args {
76 #define BTRFS_IOCTL_MAGIC 0x94
77 #define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
78 struct btrfs_ioctl_clone_range_args)
79 #define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
80 struct btrfs_ioctl_vol_args)
81 #define BTRFS_IOC_SNAP_CREATE_V2 _IOW(BTRFS_IOCTL_MAGIC, 23, \
82 struct btrfs_ioctl_vol_args_v2)
84 static struct vfs_offload_ctx *btrfs_offload_ctx;
86 struct btrfs_offload_read_state {
87 struct vfs_handle_struct *handle;
94 static void btrfs_offload_read_done(struct tevent_req *subreq);
96 static struct tevent_req *btrfs_offload_read_send(
98 struct tevent_context *ev,
99 struct vfs_handle_struct *handle,
106 struct tevent_req *req = NULL;
107 struct tevent_req *subreq = NULL;
108 struct btrfs_offload_read_state *state = NULL;
111 req = tevent_req_create(mem_ctx, &state,
112 struct btrfs_offload_read_state);
116 *state = (struct btrfs_offload_read_state) {
121 status = vfs_offload_token_ctx_init(fsp->conn->sconn->client,
123 if (tevent_req_nterror(req, status)) {
124 return tevent_req_post(req, ev);
127 if (fsctl == FSCTL_DUP_EXTENTS_TO_FILE) {
128 status = vfs_offload_token_create_blob(state, fsp, fsctl,
130 if (tevent_req_nterror(req, status)) {
131 return tevent_req_post(req, ev);
134 status = vfs_offload_token_db_store_fsp(btrfs_offload_ctx, fsp,
136 if (tevent_req_nterror(req, status)) {
137 return tevent_req_post(req, ev);
139 tevent_req_done(req);
140 return tevent_req_post(req, ev);
143 subreq = SMB_VFS_NEXT_OFFLOAD_READ_SEND(mem_ctx, ev, handle, fsp,
144 fsctl, ttl, offset, to_copy);
145 if (tevent_req_nomem(subreq, req)) {
146 return tevent_req_post(req, ev);
148 tevent_req_set_callback(subreq, btrfs_offload_read_done, req);
152 static void btrfs_offload_read_done(struct tevent_req *subreq)
154 struct tevent_req *req = tevent_req_callback_data(
155 subreq, struct tevent_req);
156 struct btrfs_offload_read_state *state = tevent_req_data(
157 req, struct btrfs_offload_read_state);
160 status = SMB_VFS_NEXT_OFFLOAD_READ_RECV(subreq,
167 if (tevent_req_nterror(req, status)) {
171 status = vfs_offload_token_db_store_fsp(btrfs_offload_ctx,
174 if (tevent_req_nterror(req, status)) {
178 tevent_req_done(req);
182 static NTSTATUS btrfs_offload_read_recv(struct tevent_req *req,
183 struct vfs_handle_struct *handle,
189 struct btrfs_offload_read_state *state = tevent_req_data(
190 req, struct btrfs_offload_read_state);
193 if (tevent_req_is_nterror(req, &status)) {
194 tevent_req_received(req);
198 *flags = state->flags;
199 *xferlen = state->xferlen;
200 token->length = state->token.length;
201 token->data = talloc_move(mem_ctx, &state->token.data);
203 tevent_req_received(req);
207 struct btrfs_offload_write_state {
208 struct vfs_handle_struct *handle;
210 bool need_unbecome_user;
213 static void btrfs_offload_write_cleanup(struct tevent_req *req,
214 enum tevent_req_state req_state)
216 struct btrfs_offload_write_state *state =
218 struct btrfs_offload_write_state);
221 if (!state->need_unbecome_user) {
225 ok = unbecome_user_without_service();
227 state->need_unbecome_user = false;
230 static void btrfs_offload_write_done(struct tevent_req *subreq);
232 static struct tevent_req *btrfs_offload_write_send(struct vfs_handle_struct *handle,
234 struct tevent_context *ev,
237 off_t transfer_offset,
238 struct files_struct *dest_fsp,
242 struct tevent_req *req = NULL;
243 struct btrfs_offload_write_state *state = NULL;
244 struct tevent_req *subreq = NULL;
245 struct btrfs_ioctl_clone_range_args cr_args;
246 struct lock_struct src_lck;
247 struct lock_struct dest_lck;
248 off_t src_off = transfer_offset;
249 files_struct *src_fsp = NULL;
251 bool handle_offload_write = true;
252 bool do_locking = false;
256 req = tevent_req_create(mem_ctx, &state,
257 struct btrfs_offload_write_state);
262 state->handle = handle;
264 tevent_req_set_cleanup_fn(req, btrfs_offload_write_cleanup);
266 status = vfs_offload_token_db_fetch_fsp(btrfs_offload_ctx,
268 if (tevent_req_nterror(req, status)) {
269 return tevent_req_post(req, ev);
273 case FSCTL_SRV_COPYCHUNK:
274 case FSCTL_SRV_COPYCHUNK_WRITE:
278 case FSCTL_DUP_EXTENTS_TO_FILE:
279 /* dup extents does not use locking */
283 handle_offload_write = false;
289 * With a @src_length of zero, BTRFS_IOC_CLONE_RANGE clones
290 * all data from @src_offset->EOF! This is certainly not what
291 * the caller expects, and not what vfs_default does.
293 handle_offload_write = false;
296 if (!handle_offload_write) {
297 subreq = SMB_VFS_NEXT_OFFLOAD_WRITE_SEND(handle,
306 if (tevent_req_nomem(subreq, req)) {
307 return tevent_req_post(req, ev);
309 tevent_req_set_callback(subreq,
310 btrfs_offload_write_done,
315 status = vfs_offload_token_check_handles(
316 fsctl, src_fsp, dest_fsp);
317 if (!NT_STATUS_IS_OK(status)) {
318 tevent_req_nterror(req, status);
319 return tevent_req_post(req, ev);
322 ok = become_user_without_service_by_fsp(src_fsp);
324 tevent_req_nterror(req, NT_STATUS_ACCESS_DENIED);
325 return tevent_req_post(req, ev);
327 state->need_unbecome_user = true;
329 status = vfs_stat_fsp(src_fsp);
330 if (tevent_req_nterror(req, status)) {
331 return tevent_req_post(req, ev);
334 if (src_fsp->fsp_name->st.st_ex_size < src_off + num) {
335 /* [MS-SMB2] Handling a Server-Side Data Copy Request */
336 tevent_req_nterror(req, NT_STATUS_INVALID_VIEW_SIZE);
337 return tevent_req_post(req, ev);
341 init_strict_lock_struct(src_fsp,
342 src_fsp->op->global->open_persistent_id,
346 lp_posix_cifsu_locktype(src_fsp),
348 if (!SMB_VFS_STRICT_LOCK_CHECK(src_fsp->conn, src_fsp, &src_lck)) {
349 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
350 return tevent_req_post(req, ev);
354 ok = unbecome_user_without_service();
356 state->need_unbecome_user = false;
359 init_strict_lock_struct(dest_fsp,
360 dest_fsp->op->global->open_persistent_id,
364 lp_posix_cifsu_locktype(dest_fsp),
367 if (!SMB_VFS_STRICT_LOCK_CHECK(dest_fsp->conn, dest_fsp, &dest_lck)) {
368 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
369 return tevent_req_post(req, ev);
373 ZERO_STRUCT(cr_args);
374 cr_args.src_fd = fsp_get_io_fd(src_fsp);
375 cr_args.src_offset = (uint64_t)src_off;
376 cr_args.dest_offset = (uint64_t)dest_off;
377 cr_args.src_length = (uint64_t)num;
379 ret = ioctl(fsp_get_io_fd(dest_fsp), BTRFS_IOC_CLONE_RANGE, &cr_args);
382 * BTRFS_IOC_CLONE_RANGE only supports 'sectorsize' aligned
383 * cloning. Which is 4096 by default, therefore fall back to
384 * manual read/write on failure.
386 DEBUG(5, ("BTRFS_IOC_CLONE_RANGE failed: %s, length %llu, "
387 "src fd: %lld off: %llu, dest fd: %d off: %llu\n",
389 (unsigned long long)cr_args.src_length,
390 (long long)cr_args.src_fd,
391 (unsigned long long)cr_args.src_offset,
392 fsp_get_io_fd(dest_fsp),
393 (unsigned long long)cr_args.dest_offset));
394 subreq = SMB_VFS_NEXT_OFFLOAD_WRITE_SEND(handle,
403 if (tevent_req_nomem(subreq, req)) {
404 return tevent_req_post(req, ev);
406 /* wait for subreq completion */
407 tevent_req_set_callback(subreq,
408 btrfs_offload_write_done,
413 DEBUG(5, ("BTRFS_IOC_CLONE_RANGE returned %d\n", ret));
414 /* BTRFS_IOC_CLONE_RANGE is all or nothing */
416 tevent_req_done(req);
417 return tevent_req_post(req, ev);
420 /* only used if the request is passed through to next VFS module */
421 static void btrfs_offload_write_done(struct tevent_req *subreq)
423 struct tevent_req *req =
424 tevent_req_callback_data(subreq,
426 struct btrfs_offload_write_state *state =
428 struct btrfs_offload_write_state);
431 status = SMB_VFS_NEXT_OFFLOAD_WRITE_RECV(state->handle,
435 if (tevent_req_nterror(req, status)) {
438 tevent_req_done(req);
441 static NTSTATUS btrfs_offload_write_recv(struct vfs_handle_struct *handle,
442 struct tevent_req *req,
445 struct btrfs_offload_write_state *state =
447 struct btrfs_offload_write_state);
450 if (tevent_req_is_nterror(req, &status)) {
451 DEBUG(4, ("server side copy chunk failed: %s\n",
453 tevent_req_received(req);
457 DEBUG(10, ("server side copy chunk copied %llu\n",
458 (unsigned long long)state->copied));
459 *copied = state->copied;
460 tevent_req_received(req);
464 static NTSTATUS btrfs_fget_compression(struct vfs_handle_struct *handle,
466 struct files_struct *fsp,
467 uint16_t *_compression_fmt)
470 const char *p = NULL;
473 int fsp_fd = fsp_get_pathref_fd(fsp);
477 if (!fsp->fsp_flags.is_pathref) {
478 ret = ioctl(fsp_fd, FS_IOC_GETFLAGS, &flags);
480 DBG_WARNING("FS_IOC_GETFLAGS failed: %s, fd %lld\n",
481 strerror(errno), (long long)fd);
482 return map_nt_error_from_unix(errno);
484 if (flags & FS_COMPR_FL) {
485 *_compression_fmt = COMPRESSION_FORMAT_LZNT1;
487 *_compression_fmt = COMPRESSION_FORMAT_NONE;
492 if (!fsp->fsp_flags.have_proc_fds) {
493 return NT_STATUS_NOT_IMPLEMENTED;
496 p = sys_proc_fd_path(fsp_fd, buf, sizeof(buf));
498 return NT_STATUS_NO_MEMORY;
501 fd = open(p, O_RDONLY);
503 DBG_DEBUG("/proc open of %s failed: %s\n", p, strerror(errno));
504 return map_nt_error_from_unix(errno);
507 ret = ioctl(fd, FS_IOC_GETFLAGS, &flags);
509 DEBUG(1, ("FS_IOC_GETFLAGS failed: %s, fd %lld\n",
510 strerror(errno), (long long)fd));
511 status = map_nt_error_from_unix(errno);
514 if (flags & FS_COMPR_FL) {
515 *_compression_fmt = COMPRESSION_FORMAT_LZNT1;
517 *_compression_fmt = COMPRESSION_FORMAT_NONE;
519 status = NT_STATUS_OK;
529 static NTSTATUS btrfs_set_compression(struct vfs_handle_struct *handle,
531 struct files_struct *fsp,
532 uint16_t compression_fmt)
539 if ((fsp == NULL) || (fsp_get_io_fd(fsp) == -1)) {
540 status = NT_STATUS_INVALID_PARAMETER;
543 fd = fsp_get_io_fd(fsp);
545 ret = ioctl(fd, FS_IOC_GETFLAGS, &flags);
547 DEBUG(1, ("FS_IOC_GETFLAGS failed: %s, fd %d\n",
548 strerror(errno), fd));
549 status = map_nt_error_from_unix(errno);
553 if (compression_fmt == COMPRESSION_FORMAT_NONE) {
554 DEBUG(5, ("setting compression\n"));
555 flags &= (~FS_COMPR_FL);
556 } else if ((compression_fmt == COMPRESSION_FORMAT_DEFAULT)
557 || (compression_fmt == COMPRESSION_FORMAT_LZNT1)) {
558 DEBUG(5, ("clearing compression\n"));
559 flags |= FS_COMPR_FL;
561 DEBUG(1, ("invalid compression format 0x%x\n",
562 (int)compression_fmt));
563 status = NT_STATUS_INVALID_PARAMETER;
567 ret = ioctl(fd, FS_IOC_SETFLAGS, &flags);
569 DEBUG(1, ("FS_IOC_SETFLAGS failed: %s, fd %d\n",
570 strerror(errno), fd));
571 status = map_nt_error_from_unix(errno);
574 status = NT_STATUS_OK;
580 * Check whether a path can be shadow copied. Return the base volume, allowing
581 * the caller to determine if multiple paths lie on the same base volume.
583 #define BTRFS_INODE_SUBVOL 256
584 static NTSTATUS btrfs_snap_check_path(struct vfs_handle_struct *handle,
586 const char *service_path,
592 if (!lp_parm_bool(SNUM(handle->conn),
593 "btrfs", "manipulate snapshots", false)) {
594 DEBUG(2, ("Btrfs snapshot manipulation disabled, passing\n"));
595 return SMB_VFS_NEXT_SNAP_CHECK_PATH(handle, mem_ctx,
596 service_path, base_volume);
599 /* btrfs userspace uses this logic to confirm subvolume */
600 if (stat(service_path, &st) < 0) {
601 return NT_STATUS_NOT_SUPPORTED;
603 if ((st.st_ino != BTRFS_INODE_SUBVOL) || !S_ISDIR(st.st_mode)) {
604 DEBUG(0, ("%s not a btrfs subvolume, snapshots not available\n",
606 return NT_STATUS_NOT_SUPPORTED;
609 /* we "snapshot" the service path itself */
610 base = talloc_strdup(mem_ctx, service_path);
612 return NT_STATUS_NO_MEMORY;
619 static NTSTATUS btrfs_gen_snap_dest_path(TALLOC_CTX *mem_ctx,
620 const char *src_path,
622 char **dest_path, char **subvolume)
628 gmtime_r(tstamp, &t_gmt);
630 tlen = strftime(time_str, ARRAY_SIZE(time_str),
631 SHADOW_COPY_PATH_FORMAT, &t_gmt);
633 return NT_STATUS_UNSUCCESSFUL;
636 *dest_path = talloc_strdup(mem_ctx, src_path);
637 *subvolume = talloc_strdup(mem_ctx, time_str);
638 if ((*dest_path == NULL) || (*subvolume == NULL)) {
639 return NT_STATUS_NO_MEMORY;
645 static NTSTATUS btrfs_snap_create(struct vfs_handle_struct *handle,
647 const char *base_volume,
653 struct btrfs_ioctl_vol_args_v2 ioctl_arg;
658 char *dest_path = NULL;
659 char *dest_subvolume = NULL;
668 if (!lp_parm_bool(SNUM(handle->conn),
669 "btrfs", "manipulate snapshots", false)) {
670 DEBUG(2, ("Btrfs snapshot manipulation disabled, passing\n"));
671 return SMB_VFS_NEXT_SNAP_CREATE(handle, mem_ctx, base_volume,
672 tstamp, rw, _base_path,
676 tmp_ctx = talloc_new(mem_ctx);
677 if (tmp_ctx == NULL) {
678 return NT_STATUS_NO_MEMORY;
681 base_path = talloc_strdup(tmp_ctx, base_volume);
682 if (base_path == NULL) {
683 talloc_free(tmp_ctx);
684 return NT_STATUS_NO_MEMORY;
687 status = btrfs_gen_snap_dest_path(tmp_ctx, base_volume, tstamp,
688 &dest_path, &dest_subvolume);
689 if (!NT_STATUS_IS_OK(status)) {
690 talloc_free(tmp_ctx);
694 snap_path = talloc_asprintf(tmp_ctx, "%s/%s", dest_path,
696 if (snap_path == NULL) {
697 talloc_free(tmp_ctx);
698 return NT_STATUS_NO_MEMORY;
701 src_dir = opendir(base_volume);
702 if (src_dir == NULL) {
703 DEBUG(0, ("snap src %s open failed: %s\n",
704 base_volume, strerror(errno)));
705 status = map_nt_error_from_unix(errno);
706 talloc_free(tmp_ctx);
709 src_fd = dirfd(src_dir);
711 status = map_nt_error_from_unix(errno);
713 talloc_free(tmp_ctx);
717 dest_dir = opendir(dest_path);
718 if (dest_dir == NULL) {
719 DEBUG(0, ("snap dest %s open failed: %s\n",
720 dest_path, strerror(errno)));
721 status = map_nt_error_from_unix(errno);
723 talloc_free(tmp_ctx);
726 dest_fd = dirfd(dest_dir);
728 status = map_nt_error_from_unix(errno);
731 talloc_free(tmp_ctx);
735 /* avoid zeroing the entire struct here, name is 4k */
736 ioctl_arg.fd = src_fd;
737 ioctl_arg.transid = 0;
738 ioctl_arg.flags = (rw == false) ? BTRFS_SUBVOL_RDONLY : 0;
739 memset(ioctl_arg.unused, 0, sizeof(ioctl_arg.unused));
740 len = strlcpy(ioctl_arg.name, dest_subvolume,
741 ARRAY_SIZE(ioctl_arg.name));
742 if (len >= ARRAY_SIZE(ioctl_arg.name)) {
743 DEBUG(1, ("subvolume name too long for SNAP_CREATE ioctl\n"));
746 talloc_free(tmp_ctx);
747 return NT_STATUS_INVALID_PARAMETER;
751 ret = ioctl(dest_fd, BTRFS_IOC_SNAP_CREATE_V2, &ioctl_arg);
755 DEBUG(0, ("%s -> %s(%s) BTRFS_IOC_SNAP_CREATE_V2 failed: %s\n",
756 base_volume, dest_path, dest_subvolume,
757 strerror(saved_errno)));
758 status = map_nt_error_from_unix(saved_errno);
761 talloc_free(tmp_ctx);
764 DEBUG(5, ("%s -> %s(%s) BTRFS_IOC_SNAP_CREATE_V2 done\n",
765 base_volume, dest_path, dest_subvolume));
767 *_base_path = talloc_steal(mem_ctx, base_path);
768 *_snap_path = talloc_steal(mem_ctx, snap_path);
771 talloc_free(tmp_ctx);
776 static NTSTATUS btrfs_snap_delete(struct vfs_handle_struct *handle,
782 struct tm t_gmt = {};
785 struct btrfs_ioctl_vol_args ioctl_arg;
794 if (!lp_parm_bool(SNUM(handle->conn),
795 "btrfs", "manipulate snapshots", false)) {
796 DEBUG(2, ("Btrfs snapshot manipulation disabled, passing\n"));
797 return SMB_VFS_NEXT_SNAP_DELETE(handle, mem_ctx,
798 base_path, snap_path);
801 tmp_ctx = talloc_new(mem_ctx);
802 if (tmp_ctx == NULL) {
803 return NT_STATUS_NO_MEMORY;
806 dest_path = talloc_strdup(tmp_ctx, snap_path);
807 if (dest_path == NULL) {
808 talloc_free(tmp_ctx);
809 return NT_STATUS_NO_MEMORY;
811 subvolume = talloc_strdup(tmp_ctx, snap_path);
812 if (subvolume == NULL) {
813 talloc_free(tmp_ctx);
814 return NT_STATUS_NO_MEMORY;
816 dest_path = dirname(dest_path);
817 subvolume = basename(subvolume);
819 /* confirm snap_path matches creation format */
820 tstr = strptime(subvolume, SHADOW_COPY_PATH_FORMAT, &t_gmt);
821 if ((tstr == NULL) || (*tstr != '\0')) {
822 DEBUG(0, ("snapshot path %s does not match creation format\n",
824 talloc_free(tmp_ctx);
825 return NT_STATUS_UNSUCCESSFUL;
828 dest_dir = opendir(dest_path);
829 if (dest_dir == NULL) {
830 DEBUG(0, ("snap destroy dest %s open failed: %s\n",
831 dest_path, strerror(errno)));
832 status = map_nt_error_from_unix(errno);
833 talloc_free(tmp_ctx);
836 dest_fd = dirfd(dest_dir);
838 status = map_nt_error_from_unix(errno);
840 talloc_free(tmp_ctx);
844 ioctl_arg.fd = -1; /* not needed */
845 len = strlcpy(ioctl_arg.name, subvolume, ARRAY_SIZE(ioctl_arg.name));
846 if (len >= ARRAY_SIZE(ioctl_arg.name)) {
847 DEBUG(1, ("subvolume name too long for SNAP_DESTROY ioctl\n"));
849 talloc_free(tmp_ctx);
850 return NT_STATUS_INVALID_PARAMETER;
854 ret = ioctl(dest_fd, BTRFS_IOC_SNAP_DESTROY, &ioctl_arg);
858 DEBUG(0, ("%s(%s) BTRFS_IOC_SNAP_DESTROY failed: %s\n",
859 dest_path, subvolume, strerror(saved_errno)));
860 status = map_nt_error_from_unix(saved_errno);
862 talloc_free(tmp_ctx);
865 DEBUG(5, ("%s(%s) BTRFS_IOC_SNAP_DESTROY done\n",
866 dest_path, subvolume));
869 talloc_free(tmp_ctx);
873 static struct vfs_fn_pointers btrfs_fns = {
874 .fs_capabilities_fn = btrfs_fs_capabilities,
875 .offload_read_send_fn = btrfs_offload_read_send,
876 .offload_read_recv_fn = btrfs_offload_read_recv,
877 .offload_write_send_fn = btrfs_offload_write_send,
878 .offload_write_recv_fn = btrfs_offload_write_recv,
879 .fget_compression_fn = btrfs_fget_compression,
880 .set_compression_fn = btrfs_set_compression,
881 .snap_check_path_fn = btrfs_snap_check_path,
882 .snap_create_fn = btrfs_snap_create,
883 .snap_delete_fn = btrfs_snap_delete,
887 NTSTATUS vfs_btrfs_init(TALLOC_CTX *ctx)
889 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION,
890 "btrfs", &btrfs_fns);