2 * Copyright (C) 2007 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/blkdev.h>
20 #include <linux/module.h>
21 #include <linux/buffer_head.h>
23 #include <linux/pagemap.h>
24 #include <linux/highmem.h>
25 #include <linux/time.h>
26 #include <linux/init.h>
27 #include <linux/seq_file.h>
28 #include <linux/string.h>
29 #include <linux/backing-dev.h>
30 #include <linux/mount.h>
31 #include <linux/mpage.h>
32 #include <linux/swap.h>
33 #include <linux/writeback.h>
34 #include <linux/statfs.h>
35 #include <linux/compat.h>
36 #include <linux/parser.h>
37 #include <linux/ctype.h>
38 #include <linux/namei.h>
39 #include <linux/miscdevice.h>
40 #include <linux/magic.h>
41 #include <linux/slab.h>
42 #include <linux/cleancache.h>
43 #include <linux/ratelimit.h>
45 #include "delayed-inode.h"
48 #include "transaction.h"
49 #include "btrfs_inode.h"
51 #include "print-tree.h"
56 #include "compression.h"
57 #include "rcu-string.h"
59 #define CREATE_TRACE_POINTS
60 #include <trace/events/btrfs.h>
62 static const struct super_operations btrfs_super_ops;
63 static struct file_system_type btrfs_fs_type;
65 static const char *btrfs_decode_error(struct btrfs_fs_info *fs_info, int errno,
72 errstr = "IO failure";
75 errstr = "Out of memory";
78 errstr = "Readonly filesystem";
81 errstr = "Object already exists";
85 if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
94 static void __save_error_info(struct btrfs_fs_info *fs_info)
97 * today we only save the error info into ram. Long term we'll
98 * also send it down to the disk
100 fs_info->fs_state = BTRFS_SUPER_FLAG_ERROR;
103 static void save_error_info(struct btrfs_fs_info *fs_info)
105 __save_error_info(fs_info);
108 /* btrfs handle error by forcing the filesystem readonly */
109 static void btrfs_handle_error(struct btrfs_fs_info *fs_info)
111 struct super_block *sb = fs_info->sb;
113 if (sb->s_flags & MS_RDONLY)
116 if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
117 sb->s_flags |= MS_RDONLY;
118 printk(KERN_INFO "btrfs is forced readonly\n");
120 * Note that a running device replace operation is not
121 * canceled here although there is no way to update
122 * the progress. It would add the risk of a deadlock,
123 * therefore the canceling is ommited. The only penalty
124 * is that some I/O remains active until the procedure
125 * completes. The next time when the filesystem is
126 * mounted writeable again, the device replace
127 * operation continues.
135 * __btrfs_std_error decodes expected errors from the caller and
136 * invokes the approciate error response.
138 void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
139 unsigned int line, int errno, const char *fmt, ...)
141 struct super_block *sb = fs_info->sb;
148 * Special case: if the error is EROFS, and we're already
149 * under MS_RDONLY, then it is safe here.
151 if (errno == -EROFS && (sb->s_flags & MS_RDONLY))
154 errstr = btrfs_decode_error(fs_info, errno, nbuf);
156 struct va_format vaf = {
161 printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s (%pV)\n",
162 sb->s_id, function, line, errstr, &vaf);
164 printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s\n",
165 sb->s_id, function, line, errstr);
168 /* Don't go through full error handling during mount */
169 if (sb->s_flags & MS_BORN) {
170 save_error_info(fs_info);
171 btrfs_handle_error(fs_info);
176 static const char * const logtypes[] = {
187 void btrfs_printk(struct btrfs_fs_info *fs_info, const char *fmt, ...)
189 struct super_block *sb = fs_info->sb;
191 struct va_format vaf;
193 const char *type = logtypes[4];
198 kern_level = printk_get_level(fmt);
200 size_t size = printk_skip_level(fmt) - fmt;
201 memcpy(lvl, fmt, size);
204 type = logtypes[kern_level - '0'];
211 printk("%sBTRFS %s (device %s): %pV", lvl, type, sb->s_id, &vaf);
218 void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function,
219 unsigned int line, int errno, const char *fmt, ...)
221 struct super_block *sb = fs_info->sb;
224 * Special case: if the error is EROFS, and we're already
225 * under MS_RDONLY, then it is safe here.
227 if (errno == -EROFS && (sb->s_flags & MS_RDONLY))
230 /* Don't go through full error handling during mount */
231 if (sb->s_flags & MS_BORN) {
232 save_error_info(fs_info);
233 btrfs_handle_error(fs_info);
239 * We only mark the transaction aborted and then set the file system read-only.
240 * This will prevent new transactions from starting or trying to join this
243 * This means that error recovery at the call site is limited to freeing
244 * any local memory allocations and passing the error code up without
245 * further cleanup. The transaction should complete as it normally would
246 * in the call path but will return -EIO.
248 * We'll complete the cleanup in btrfs_end_transaction and
249 * btrfs_commit_transaction.
251 void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
252 struct btrfs_root *root, const char *function,
253 unsigned int line, int errno)
255 WARN_ONCE(1, KERN_DEBUG "btrfs: Transaction aborted\n");
256 trans->aborted = errno;
257 /* Nothing used. The other threads that have joined this
258 * transaction may be able to continue. */
259 if (!trans->blocks_used) {
263 errstr = btrfs_decode_error(root->fs_info, errno, nbuf);
264 btrfs_printk(root->fs_info,
265 "%s:%d: Aborting unused transaction(%s).\n",
266 function, line, errstr);
269 trans->transaction->aborted = errno;
270 __btrfs_std_error(root->fs_info, function, line, errno, NULL);
273 * __btrfs_panic decodes unexpected, fatal errors from the caller,
274 * issues an alert, and either panics or BUGs, depending on mount options.
276 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
277 unsigned int line, int errno, const char *fmt, ...)
280 char *s_id = "<unknown>";
282 struct va_format vaf = { .fmt = fmt };
286 s_id = fs_info->sb->s_id;
291 errstr = btrfs_decode_error(fs_info, errno, nbuf);
292 if (fs_info->mount_opt & BTRFS_MOUNT_PANIC_ON_FATAL_ERROR)
293 panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
294 s_id, function, line, &vaf, errstr);
296 printk(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
297 s_id, function, line, &vaf, errstr);
299 /* Caller calls BUG() */
302 static void btrfs_put_super(struct super_block *sb)
304 (void)close_ctree(btrfs_sb(sb)->tree_root);
305 /* FIXME: need to fix VFS to return error? */
306 /* AV: return it _where_? ->put_super() can be triggered by any number
307 * of async events, up to and including delivery of SIGKILL to the
308 * last process that kept it busy. Or segfault in the aforementioned
309 * process... Whom would you report that to?
314 Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum,
315 Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd,
316 Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress,
317 Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
318 Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
319 Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
320 Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache,
321 Opt_no_space_cache, Opt_recovery, Opt_skip_balance,
322 Opt_check_integrity, Opt_check_integrity_including_extent_data,
323 Opt_check_integrity_print_mask, Opt_fatal_errors,
327 static match_table_t tokens = {
328 {Opt_degraded, "degraded"},
329 {Opt_subvol, "subvol=%s"},
330 {Opt_subvolid, "subvolid=%d"},
331 {Opt_device, "device=%s"},
332 {Opt_nodatasum, "nodatasum"},
333 {Opt_nodatacow, "nodatacow"},
334 {Opt_nobarrier, "nobarrier"},
335 {Opt_max_inline, "max_inline=%s"},
336 {Opt_alloc_start, "alloc_start=%s"},
337 {Opt_thread_pool, "thread_pool=%d"},
338 {Opt_compress, "compress"},
339 {Opt_compress_type, "compress=%s"},
340 {Opt_compress_force, "compress-force"},
341 {Opt_compress_force_type, "compress-force=%s"},
343 {Opt_ssd_spread, "ssd_spread"},
344 {Opt_nossd, "nossd"},
345 {Opt_noacl, "noacl"},
346 {Opt_notreelog, "notreelog"},
347 {Opt_flushoncommit, "flushoncommit"},
348 {Opt_ratio, "metadata_ratio=%d"},
349 {Opt_discard, "discard"},
350 {Opt_space_cache, "space_cache"},
351 {Opt_clear_cache, "clear_cache"},
352 {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"},
353 {Opt_enospc_debug, "enospc_debug"},
354 {Opt_subvolrootid, "subvolrootid=%d"},
355 {Opt_defrag, "autodefrag"},
356 {Opt_inode_cache, "inode_cache"},
357 {Opt_no_space_cache, "nospace_cache"},
358 {Opt_recovery, "recovery"},
359 {Opt_skip_balance, "skip_balance"},
360 {Opt_check_integrity, "check_int"},
361 {Opt_check_integrity_including_extent_data, "check_int_data"},
362 {Opt_check_integrity_print_mask, "check_int_print_mask=%d"},
363 {Opt_fatal_errors, "fatal_errors=%s"},
368 * Regular mount options parser. Everything that is needed only when
369 * reading in a new superblock is parsed here.
370 * XXX JDM: This needs to be cleaned up for remount.
372 int btrfs_parse_options(struct btrfs_root *root, char *options)
374 struct btrfs_fs_info *info = root->fs_info;
375 substring_t args[MAX_OPT_ARGS];
376 char *p, *num, *orig = NULL;
381 bool compress_force = false;
383 cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy);
385 btrfs_set_opt(info->mount_opt, SPACE_CACHE);
391 * strsep changes the string, duplicate it because parse_options
394 options = kstrdup(options, GFP_NOFS);
400 while ((p = strsep(&options, ",")) != NULL) {
405 token = match_token(p, tokens, args);
408 printk(KERN_INFO "btrfs: allowing degraded mounts\n");
409 btrfs_set_opt(info->mount_opt, DEGRADED);
413 case Opt_subvolrootid:
416 * These are parsed by btrfs_parse_early_options
417 * and can be happily ignored here.
421 printk(KERN_INFO "btrfs: setting nodatasum\n");
422 btrfs_set_opt(info->mount_opt, NODATASUM);
425 if (!btrfs_test_opt(root, COMPRESS) ||
426 !btrfs_test_opt(root, FORCE_COMPRESS)) {
427 printk(KERN_INFO "btrfs: setting nodatacow, compression disabled\n");
429 printk(KERN_INFO "btrfs: setting nodatacow\n");
431 info->compress_type = BTRFS_COMPRESS_NONE;
432 btrfs_clear_opt(info->mount_opt, COMPRESS);
433 btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
434 btrfs_set_opt(info->mount_opt, NODATACOW);
435 btrfs_set_opt(info->mount_opt, NODATASUM);
437 case Opt_compress_force:
438 case Opt_compress_force_type:
439 compress_force = true;
441 case Opt_compress_type:
442 if (token == Opt_compress ||
443 token == Opt_compress_force ||
444 strcmp(args[0].from, "zlib") == 0) {
445 compress_type = "zlib";
446 info->compress_type = BTRFS_COMPRESS_ZLIB;
447 btrfs_set_opt(info->mount_opt, COMPRESS);
448 btrfs_clear_opt(info->mount_opt, NODATACOW);
449 btrfs_clear_opt(info->mount_opt, NODATASUM);
450 } else if (strcmp(args[0].from, "lzo") == 0) {
451 compress_type = "lzo";
452 info->compress_type = BTRFS_COMPRESS_LZO;
453 btrfs_set_opt(info->mount_opt, COMPRESS);
454 btrfs_clear_opt(info->mount_opt, NODATACOW);
455 btrfs_clear_opt(info->mount_opt, NODATASUM);
456 btrfs_set_fs_incompat(info, COMPRESS_LZO);
457 } else if (strncmp(args[0].from, "no", 2) == 0) {
458 compress_type = "no";
459 info->compress_type = BTRFS_COMPRESS_NONE;
460 btrfs_clear_opt(info->mount_opt, COMPRESS);
461 btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
462 compress_force = false;
468 if (compress_force) {
469 btrfs_set_opt(info->mount_opt, FORCE_COMPRESS);
470 pr_info("btrfs: force %s compression\n",
473 pr_info("btrfs: use %s compression\n",
477 printk(KERN_INFO "btrfs: use ssd allocation scheme\n");
478 btrfs_set_opt(info->mount_opt, SSD);
481 printk(KERN_INFO "btrfs: use spread ssd "
482 "allocation scheme\n");
483 btrfs_set_opt(info->mount_opt, SSD);
484 btrfs_set_opt(info->mount_opt, SSD_SPREAD);
487 printk(KERN_INFO "btrfs: not using ssd allocation "
489 btrfs_set_opt(info->mount_opt, NOSSD);
490 btrfs_clear_opt(info->mount_opt, SSD);
491 btrfs_clear_opt(info->mount_opt, SSD_SPREAD);
494 printk(KERN_INFO "btrfs: turning off barriers\n");
495 btrfs_set_opt(info->mount_opt, NOBARRIER);
497 case Opt_thread_pool:
499 match_int(&args[0], &intarg);
501 info->thread_pool_size = intarg;
504 num = match_strdup(&args[0]);
506 info->max_inline = memparse(num, NULL);
509 if (info->max_inline) {
510 info->max_inline = max_t(u64,
514 printk(KERN_INFO "btrfs: max_inline at %llu\n",
515 (unsigned long long)info->max_inline);
518 case Opt_alloc_start:
519 num = match_strdup(&args[0]);
521 info->alloc_start = memparse(num, NULL);
524 "btrfs: allocations start at %llu\n",
525 (unsigned long long)info->alloc_start);
529 root->fs_info->sb->s_flags &= ~MS_POSIXACL;
532 printk(KERN_INFO "btrfs: disabling tree log\n");
533 btrfs_set_opt(info->mount_opt, NOTREELOG);
535 case Opt_flushoncommit:
536 printk(KERN_INFO "btrfs: turning on flush-on-commit\n");
537 btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT);
541 match_int(&args[0], &intarg);
543 info->metadata_ratio = intarg;
544 printk(KERN_INFO "btrfs: metadata ratio %d\n",
545 info->metadata_ratio);
549 btrfs_set_opt(info->mount_opt, DISCARD);
551 case Opt_space_cache:
552 btrfs_set_opt(info->mount_opt, SPACE_CACHE);
554 case Opt_no_space_cache:
555 printk(KERN_INFO "btrfs: disabling disk space caching\n");
556 btrfs_clear_opt(info->mount_opt, SPACE_CACHE);
558 case Opt_inode_cache:
559 printk(KERN_INFO "btrfs: enabling inode map caching\n");
560 btrfs_set_opt(info->mount_opt, INODE_MAP_CACHE);
562 case Opt_clear_cache:
563 printk(KERN_INFO "btrfs: force clearing of disk cache\n");
564 btrfs_set_opt(info->mount_opt, CLEAR_CACHE);
566 case Opt_user_subvol_rm_allowed:
567 btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED);
569 case Opt_enospc_debug:
570 btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG);
573 printk(KERN_INFO "btrfs: enabling auto defrag\n");
574 btrfs_set_opt(info->mount_opt, AUTO_DEFRAG);
577 printk(KERN_INFO "btrfs: enabling auto recovery\n");
578 btrfs_set_opt(info->mount_opt, RECOVERY);
580 case Opt_skip_balance:
581 btrfs_set_opt(info->mount_opt, SKIP_BALANCE);
583 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
584 case Opt_check_integrity_including_extent_data:
585 printk(KERN_INFO "btrfs: enabling check integrity"
586 " including extent data\n");
587 btrfs_set_opt(info->mount_opt,
588 CHECK_INTEGRITY_INCLUDING_EXTENT_DATA);
589 btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
591 case Opt_check_integrity:
592 printk(KERN_INFO "btrfs: enabling check integrity\n");
593 btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
595 case Opt_check_integrity_print_mask:
597 match_int(&args[0], &intarg);
599 info->check_integrity_print_mask = intarg;
600 printk(KERN_INFO "btrfs:"
601 " check_integrity_print_mask 0x%x\n",
602 info->check_integrity_print_mask);
606 case Opt_check_integrity_including_extent_data:
607 case Opt_check_integrity:
608 case Opt_check_integrity_print_mask:
609 printk(KERN_ERR "btrfs: support for check_integrity*"
610 " not compiled in!\n");
614 case Opt_fatal_errors:
615 if (strcmp(args[0].from, "panic") == 0)
616 btrfs_set_opt(info->mount_opt,
617 PANIC_ON_FATAL_ERROR);
618 else if (strcmp(args[0].from, "bug") == 0)
619 btrfs_clear_opt(info->mount_opt,
620 PANIC_ON_FATAL_ERROR);
627 printk(KERN_INFO "btrfs: unrecognized mount option "
636 if (!ret && btrfs_test_opt(root, SPACE_CACHE))
637 printk(KERN_INFO "btrfs: disk space caching is enabled\n");
643 * Parse mount options that are required early in the mount process.
645 * All other options will be parsed on much later in the mount process and
646 * only when we need to allocate a new super block.
648 static int btrfs_parse_early_options(const char *options, fmode_t flags,
649 void *holder, char **subvol_name, u64 *subvol_objectid,
650 u64 *subvol_rootid, struct btrfs_fs_devices **fs_devices)
652 substring_t args[MAX_OPT_ARGS];
653 char *device_name, *opts, *orig, *p;
661 * strsep changes the string, duplicate it because parse_options
664 opts = kstrdup(options, GFP_KERNEL);
669 while ((p = strsep(&opts, ",")) != NULL) {
674 token = match_token(p, tokens, args);
678 *subvol_name = match_strdup(&args[0]);
682 error = match_int(&args[0], &intarg);
684 /* we want the original fs_tree */
687 BTRFS_FS_TREE_OBJECTID;
689 *subvol_objectid = intarg;
692 case Opt_subvolrootid:
694 error = match_int(&args[0], &intarg);
696 /* we want the original fs_tree */
699 BTRFS_FS_TREE_OBJECTID;
701 *subvol_rootid = intarg;
705 device_name = match_strdup(&args[0]);
710 error = btrfs_scan_one_device(device_name,
711 flags, holder, fs_devices);
726 static struct dentry *get_default_root(struct super_block *sb,
729 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
730 struct btrfs_root *root = fs_info->tree_root;
731 struct btrfs_root *new_root;
732 struct btrfs_dir_item *di;
733 struct btrfs_path *path;
734 struct btrfs_key location;
740 * We have a specific subvol we want to mount, just setup location and
741 * go look up the root.
743 if (subvol_objectid) {
744 location.objectid = subvol_objectid;
745 location.type = BTRFS_ROOT_ITEM_KEY;
746 location.offset = (u64)-1;
750 path = btrfs_alloc_path();
752 return ERR_PTR(-ENOMEM);
753 path->leave_spinning = 1;
756 * Find the "default" dir item which points to the root item that we
757 * will mount by default if we haven't been given a specific subvolume
760 dir_id = btrfs_super_root_dir(fs_info->super_copy);
761 di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0);
763 btrfs_free_path(path);
768 * Ok the default dir item isn't there. This is weird since
769 * it's always been there, but don't freak out, just try and
770 * mount to root most subvolume.
772 btrfs_free_path(path);
773 dir_id = BTRFS_FIRST_FREE_OBJECTID;
774 new_root = fs_info->fs_root;
778 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
779 btrfs_free_path(path);
782 new_root = btrfs_read_fs_root_no_name(fs_info, &location);
783 if (IS_ERR(new_root))
784 return ERR_CAST(new_root);
786 if (btrfs_root_refs(&new_root->root_item) == 0)
787 return ERR_PTR(-ENOENT);
789 dir_id = btrfs_root_dirid(&new_root->root_item);
791 location.objectid = dir_id;
792 location.type = BTRFS_INODE_ITEM_KEY;
795 inode = btrfs_iget(sb, &location, new_root, &new);
797 return ERR_CAST(inode);
800 * If we're just mounting the root most subvol put the inode and return
801 * a reference to the dentry. We will have already gotten a reference
802 * to the inode in btrfs_fill_super so we're good to go.
804 if (!new && sb->s_root->d_inode == inode) {
806 return dget(sb->s_root);
809 return d_obtain_alias(inode);
812 static int btrfs_fill_super(struct super_block *sb,
813 struct btrfs_fs_devices *fs_devices,
814 void *data, int silent)
817 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
818 struct btrfs_key key;
821 sb->s_maxbytes = MAX_LFS_FILESIZE;
822 sb->s_magic = BTRFS_SUPER_MAGIC;
823 sb->s_op = &btrfs_super_ops;
824 sb->s_d_op = &btrfs_dentry_operations;
825 sb->s_export_op = &btrfs_export_ops;
826 sb->s_xattr = btrfs_xattr_handlers;
828 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
829 sb->s_flags |= MS_POSIXACL;
831 sb->s_flags |= MS_I_VERSION;
832 err = open_ctree(sb, fs_devices, (char *)data);
834 printk("btrfs: open_ctree failed\n");
838 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
839 key.type = BTRFS_INODE_ITEM_KEY;
841 inode = btrfs_iget(sb, &key, fs_info->fs_root, NULL);
843 err = PTR_ERR(inode);
847 sb->s_root = d_make_root(inode);
853 save_mount_options(sb, data);
854 cleancache_init_fs(sb);
855 sb->s_flags |= MS_ACTIVE;
859 close_ctree(fs_info->tree_root);
863 int btrfs_sync_fs(struct super_block *sb, int wait)
865 struct btrfs_trans_handle *trans;
866 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
867 struct btrfs_root *root = fs_info->tree_root;
869 trace_btrfs_sync_fs(wait);
872 filemap_flush(fs_info->btree_inode->i_mapping);
876 btrfs_wait_ordered_extents(root, 0);
878 trans = btrfs_attach_transaction(root);
880 /* no transaction, don't bother */
881 if (PTR_ERR(trans) == -ENOENT)
883 return PTR_ERR(trans);
885 return btrfs_commit_transaction(trans, root);
888 static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry)
890 struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb);
891 struct btrfs_root *root = info->tree_root;
894 if (btrfs_test_opt(root, DEGRADED))
895 seq_puts(seq, ",degraded");
896 if (btrfs_test_opt(root, NODATASUM))
897 seq_puts(seq, ",nodatasum");
898 if (btrfs_test_opt(root, NODATACOW))
899 seq_puts(seq, ",nodatacow");
900 if (btrfs_test_opt(root, NOBARRIER))
901 seq_puts(seq, ",nobarrier");
902 if (info->max_inline != 8192 * 1024)
903 seq_printf(seq, ",max_inline=%llu",
904 (unsigned long long)info->max_inline);
905 if (info->alloc_start != 0)
906 seq_printf(seq, ",alloc_start=%llu",
907 (unsigned long long)info->alloc_start);
908 if (info->thread_pool_size != min_t(unsigned long,
909 num_online_cpus() + 2, 8))
910 seq_printf(seq, ",thread_pool=%d", info->thread_pool_size);
911 if (btrfs_test_opt(root, COMPRESS)) {
912 if (info->compress_type == BTRFS_COMPRESS_ZLIB)
913 compress_type = "zlib";
915 compress_type = "lzo";
916 if (btrfs_test_opt(root, FORCE_COMPRESS))
917 seq_printf(seq, ",compress-force=%s", compress_type);
919 seq_printf(seq, ",compress=%s", compress_type);
921 if (btrfs_test_opt(root, NOSSD))
922 seq_puts(seq, ",nossd");
923 if (btrfs_test_opt(root, SSD_SPREAD))
924 seq_puts(seq, ",ssd_spread");
925 else if (btrfs_test_opt(root, SSD))
926 seq_puts(seq, ",ssd");
927 if (btrfs_test_opt(root, NOTREELOG))
928 seq_puts(seq, ",notreelog");
929 if (btrfs_test_opt(root, FLUSHONCOMMIT))
930 seq_puts(seq, ",flushoncommit");
931 if (btrfs_test_opt(root, DISCARD))
932 seq_puts(seq, ",discard");
933 if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
934 seq_puts(seq, ",noacl");
935 if (btrfs_test_opt(root, SPACE_CACHE))
936 seq_puts(seq, ",space_cache");
938 seq_puts(seq, ",nospace_cache");
939 if (btrfs_test_opt(root, CLEAR_CACHE))
940 seq_puts(seq, ",clear_cache");
941 if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
942 seq_puts(seq, ",user_subvol_rm_allowed");
943 if (btrfs_test_opt(root, ENOSPC_DEBUG))
944 seq_puts(seq, ",enospc_debug");
945 if (btrfs_test_opt(root, AUTO_DEFRAG))
946 seq_puts(seq, ",autodefrag");
947 if (btrfs_test_opt(root, INODE_MAP_CACHE))
948 seq_puts(seq, ",inode_cache");
949 if (btrfs_test_opt(root, SKIP_BALANCE))
950 seq_puts(seq, ",skip_balance");
951 if (btrfs_test_opt(root, PANIC_ON_FATAL_ERROR))
952 seq_puts(seq, ",fatal_errors=panic");
956 static int btrfs_test_super(struct super_block *s, void *data)
958 struct btrfs_fs_info *p = data;
959 struct btrfs_fs_info *fs_info = btrfs_sb(s);
961 return fs_info->fs_devices == p->fs_devices;
964 static int btrfs_set_super(struct super_block *s, void *data)
966 int err = set_anon_super(s, data);
973 * subvolumes are identified by ino 256
975 static inline int is_subvolume_inode(struct inode *inode)
977 if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
983 * This will strip out the subvol=%s argument for an argument string and add
984 * subvolid=0 to make sure we get the actual tree root for path walking to the
987 static char *setup_root_args(char *args)
989 unsigned len = strlen(args) + 2 + 1;
990 char *src, *dst, *buf;
993 * We need the same args as before, but with this substitution:
994 * s!subvol=[^,]+!subvolid=0!
996 * Since the replacement string is up to 2 bytes longer than the
997 * original, allocate strlen(args) + 2 + 1 bytes.
1000 src = strstr(args, "subvol=");
1001 /* This shouldn't happen, but just in case.. */
1005 buf = dst = kmalloc(len, GFP_NOFS);
1010 * If the subvol= arg is not at the start of the string,
1011 * copy whatever precedes it into buf.
1016 dst += strlen(args);
1019 strcpy(dst, "subvolid=0");
1020 dst += strlen("subvolid=0");
1023 * If there is a "," after the original subvol=... string,
1024 * copy that suffix into our buffer. Otherwise, we're done.
1026 src = strchr(src, ',');
1033 static struct dentry *mount_subvol(const char *subvol_name, int flags,
1034 const char *device_name, char *data)
1036 struct dentry *root;
1037 struct vfsmount *mnt;
1040 newargs = setup_root_args(data);
1042 return ERR_PTR(-ENOMEM);
1043 mnt = vfs_kern_mount(&btrfs_fs_type, flags, device_name,
1047 return ERR_CAST(mnt);
1049 root = mount_subtree(mnt, subvol_name);
1051 if (!IS_ERR(root) && !is_subvolume_inode(root->d_inode)) {
1052 struct super_block *s = root->d_sb;
1054 root = ERR_PTR(-EINVAL);
1055 deactivate_locked_super(s);
1056 printk(KERN_ERR "btrfs: '%s' is not a valid subvolume\n",
1064 * Find a superblock for the given device / mount point.
1066 * Note: This is based on get_sb_bdev from fs/super.c with a few additions
1067 * for multiple device setup. Make sure to keep it in sync.
1069 static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
1070 const char *device_name, void *data)
1072 struct block_device *bdev = NULL;
1073 struct super_block *s;
1074 struct dentry *root;
1075 struct btrfs_fs_devices *fs_devices = NULL;
1076 struct btrfs_fs_info *fs_info = NULL;
1077 fmode_t mode = FMODE_READ;
1078 char *subvol_name = NULL;
1079 u64 subvol_objectid = 0;
1080 u64 subvol_rootid = 0;
1083 if (!(flags & MS_RDONLY))
1084 mode |= FMODE_WRITE;
1086 error = btrfs_parse_early_options(data, mode, fs_type,
1087 &subvol_name, &subvol_objectid,
1088 &subvol_rootid, &fs_devices);
1091 return ERR_PTR(error);
1095 root = mount_subvol(subvol_name, flags, device_name, data);
1100 error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices);
1102 return ERR_PTR(error);
1105 * Setup a dummy root and fs_info for test/set super. This is because
1106 * we don't actually fill this stuff out until open_ctree, but we need
1107 * it for searching for existing supers, so this lets us do that and
1108 * then open_ctree will properly initialize everything later.
1110 fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS);
1112 return ERR_PTR(-ENOMEM);
1114 fs_info->fs_devices = fs_devices;
1116 fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS);
1117 fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_NOFS);
1118 if (!fs_info->super_copy || !fs_info->super_for_commit) {
1123 error = btrfs_open_devices(fs_devices, mode, fs_type);
1127 if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) {
1129 goto error_close_devices;
1132 bdev = fs_devices->latest_bdev;
1133 s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | MS_NOSEC,
1137 goto error_close_devices;
1141 btrfs_close_devices(fs_devices);
1142 free_fs_info(fs_info);
1143 if ((flags ^ s->s_flags) & MS_RDONLY)
1146 char b[BDEVNAME_SIZE];
1148 strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
1149 btrfs_sb(s)->bdev_holder = fs_type;
1150 error = btrfs_fill_super(s, fs_devices, data,
1151 flags & MS_SILENT ? 1 : 0);
1154 root = !error ? get_default_root(s, subvol_objectid) : ERR_PTR(error);
1156 deactivate_locked_super(s);
1160 error_close_devices:
1161 btrfs_close_devices(fs_devices);
1163 free_fs_info(fs_info);
1164 return ERR_PTR(error);
1167 static void btrfs_set_max_workers(struct btrfs_workers *workers, int new_limit)
1169 spin_lock_irq(&workers->lock);
1170 workers->max_workers = new_limit;
1171 spin_unlock_irq(&workers->lock);
1174 static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info,
1175 int new_pool_size, int old_pool_size)
1177 if (new_pool_size == old_pool_size)
1180 fs_info->thread_pool_size = new_pool_size;
1182 printk(KERN_INFO "btrfs: resize thread pool %d -> %d\n",
1183 old_pool_size, new_pool_size);
1185 btrfs_set_max_workers(&fs_info->generic_worker, new_pool_size);
1186 btrfs_set_max_workers(&fs_info->workers, new_pool_size);
1187 btrfs_set_max_workers(&fs_info->delalloc_workers, new_pool_size);
1188 btrfs_set_max_workers(&fs_info->submit_workers, new_pool_size);
1189 btrfs_set_max_workers(&fs_info->caching_workers, new_pool_size);
1190 btrfs_set_max_workers(&fs_info->fixup_workers, new_pool_size);
1191 btrfs_set_max_workers(&fs_info->endio_workers, new_pool_size);
1192 btrfs_set_max_workers(&fs_info->endio_meta_workers, new_pool_size);
1193 btrfs_set_max_workers(&fs_info->endio_meta_write_workers, new_pool_size);
1194 btrfs_set_max_workers(&fs_info->endio_write_workers, new_pool_size);
1195 btrfs_set_max_workers(&fs_info->endio_freespace_worker, new_pool_size);
1196 btrfs_set_max_workers(&fs_info->delayed_workers, new_pool_size);
1197 btrfs_set_max_workers(&fs_info->readahead_workers, new_pool_size);
1198 btrfs_set_max_workers(&fs_info->scrub_workers, new_pool_size);
1201 static int btrfs_remount(struct super_block *sb, int *flags, char *data)
1203 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1204 struct btrfs_root *root = fs_info->tree_root;
1205 unsigned old_flags = sb->s_flags;
1206 unsigned long old_opts = fs_info->mount_opt;
1207 unsigned long old_compress_type = fs_info->compress_type;
1208 u64 old_max_inline = fs_info->max_inline;
1209 u64 old_alloc_start = fs_info->alloc_start;
1210 int old_thread_pool_size = fs_info->thread_pool_size;
1211 unsigned int old_metadata_ratio = fs_info->metadata_ratio;
1214 ret = btrfs_parse_options(root, data);
1220 btrfs_resize_thread_pool(fs_info,
1221 fs_info->thread_pool_size, old_thread_pool_size);
1223 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1226 if (*flags & MS_RDONLY) {
1227 sb->s_flags |= MS_RDONLY;
1229 ret = btrfs_commit_super(root);
1233 if (fs_info->fs_devices->rw_devices == 0) {
1238 if (fs_info->fs_devices->missing_devices >
1239 fs_info->num_tolerated_disk_barrier_failures &&
1240 !(*flags & MS_RDONLY)) {
1242 "Btrfs: too many missing devices, writeable remount is not allowed\n");
1247 if (btrfs_super_log_root(fs_info->super_copy) != 0) {
1252 ret = btrfs_cleanup_fs_roots(fs_info);
1256 /* recover relocation */
1257 ret = btrfs_recover_relocation(root);
1261 ret = btrfs_resume_balance_async(fs_info);
1265 sb->s_flags &= ~MS_RDONLY;
1271 /* We've hit an error - don't reset MS_RDONLY */
1272 if (sb->s_flags & MS_RDONLY)
1273 old_flags |= MS_RDONLY;
1274 sb->s_flags = old_flags;
1275 fs_info->mount_opt = old_opts;
1276 fs_info->compress_type = old_compress_type;
1277 fs_info->max_inline = old_max_inline;
1278 fs_info->alloc_start = old_alloc_start;
1279 btrfs_resize_thread_pool(fs_info,
1280 old_thread_pool_size, fs_info->thread_pool_size);
1281 fs_info->metadata_ratio = old_metadata_ratio;
1285 /* Used to sort the devices by max_avail(descending sort) */
1286 static int btrfs_cmp_device_free_bytes(const void *dev_info1,
1287 const void *dev_info2)
1289 if (((struct btrfs_device_info *)dev_info1)->max_avail >
1290 ((struct btrfs_device_info *)dev_info2)->max_avail)
1292 else if (((struct btrfs_device_info *)dev_info1)->max_avail <
1293 ((struct btrfs_device_info *)dev_info2)->max_avail)
1300 * sort the devices by max_avail, in which max free extent size of each device
1301 * is stored.(Descending Sort)
1303 static inline void btrfs_descending_sort_devices(
1304 struct btrfs_device_info *devices,
1307 sort(devices, nr_devices, sizeof(struct btrfs_device_info),
1308 btrfs_cmp_device_free_bytes, NULL);
1312 * The helper to calc the free space on the devices that can be used to store
1315 static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes)
1317 struct btrfs_fs_info *fs_info = root->fs_info;
1318 struct btrfs_device_info *devices_info;
1319 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
1320 struct btrfs_device *device;
1325 u64 min_stripe_size;
1326 int min_stripes = 1, num_stripes = 1;
1327 int i = 0, nr_devices;
1330 nr_devices = fs_info->fs_devices->open_devices;
1331 BUG_ON(!nr_devices);
1333 devices_info = kmalloc(sizeof(*devices_info) * nr_devices,
1338 /* calc min stripe number for data space alloction */
1339 type = btrfs_get_alloc_profile(root, 1);
1340 if (type & BTRFS_BLOCK_GROUP_RAID0) {
1342 num_stripes = nr_devices;
1343 } else if (type & BTRFS_BLOCK_GROUP_RAID1) {
1346 } else if (type & BTRFS_BLOCK_GROUP_RAID10) {
1351 if (type & BTRFS_BLOCK_GROUP_DUP)
1352 min_stripe_size = 2 * BTRFS_STRIPE_LEN;
1354 min_stripe_size = BTRFS_STRIPE_LEN;
1356 list_for_each_entry(device, &fs_devices->devices, dev_list) {
1357 if (!device->in_fs_metadata || !device->bdev)
1360 avail_space = device->total_bytes - device->bytes_used;
1362 /* align with stripe_len */
1363 do_div(avail_space, BTRFS_STRIPE_LEN);
1364 avail_space *= BTRFS_STRIPE_LEN;
1367 * In order to avoid overwritting the superblock on the drive,
1368 * btrfs starts at an offset of at least 1MB when doing chunk
1371 skip_space = 1024 * 1024;
1373 /* user can set the offset in fs_info->alloc_start. */
1374 if (fs_info->alloc_start + BTRFS_STRIPE_LEN <=
1375 device->total_bytes)
1376 skip_space = max(fs_info->alloc_start, skip_space);
1379 * btrfs can not use the free space in [0, skip_space - 1],
1380 * we must subtract it from the total. In order to implement
1381 * it, we account the used space in this range first.
1383 ret = btrfs_account_dev_extents_size(device, 0, skip_space - 1,
1386 kfree(devices_info);
1390 /* calc the free space in [0, skip_space - 1] */
1391 skip_space -= used_space;
1394 * we can use the free space in [0, skip_space - 1], subtract
1395 * it from the total.
1397 if (avail_space && avail_space >= skip_space)
1398 avail_space -= skip_space;
1402 if (avail_space < min_stripe_size)
1405 devices_info[i].dev = device;
1406 devices_info[i].max_avail = avail_space;
1413 btrfs_descending_sort_devices(devices_info, nr_devices);
1417 while (nr_devices >= min_stripes) {
1418 if (num_stripes > nr_devices)
1419 num_stripes = nr_devices;
1421 if (devices_info[i].max_avail >= min_stripe_size) {
1425 avail_space += devices_info[i].max_avail * num_stripes;
1426 alloc_size = devices_info[i].max_avail;
1427 for (j = i + 1 - num_stripes; j <= i; j++)
1428 devices_info[j].max_avail -= alloc_size;
1434 kfree(devices_info);
1435 *free_bytes = avail_space;
1439 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
1441 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
1442 struct btrfs_super_block *disk_super = fs_info->super_copy;
1443 struct list_head *head = &fs_info->space_info;
1444 struct btrfs_space_info *found;
1446 u64 total_free_data = 0;
1447 int bits = dentry->d_sb->s_blocksize_bits;
1448 __be32 *fsid = (__be32 *)fs_info->fsid;
1451 /* holding chunk_muext to avoid allocating new chunks */
1452 mutex_lock(&fs_info->chunk_mutex);
1454 list_for_each_entry_rcu(found, head, list) {
1455 if (found->flags & BTRFS_BLOCK_GROUP_DATA) {
1456 total_free_data += found->disk_total - found->disk_used;
1458 btrfs_account_ro_block_groups_free_space(found);
1461 total_used += found->disk_used;
1465 buf->f_namelen = BTRFS_NAME_LEN;
1466 buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
1467 buf->f_bfree = buf->f_blocks - (total_used >> bits);
1468 buf->f_bsize = dentry->d_sb->s_blocksize;
1469 buf->f_type = BTRFS_SUPER_MAGIC;
1470 buf->f_bavail = total_free_data;
1471 ret = btrfs_calc_avail_data_space(fs_info->tree_root, &total_free_data);
1473 mutex_unlock(&fs_info->chunk_mutex);
1476 buf->f_bavail += total_free_data;
1477 buf->f_bavail = buf->f_bavail >> bits;
1478 mutex_unlock(&fs_info->chunk_mutex);
1480 /* We treat it as constant endianness (it doesn't matter _which_)
1481 because we want the fsid to come out the same whether mounted
1482 on a big-endian or little-endian host */
1483 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
1484 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
1485 /* Mask in the root object ID too, to disambiguate subvols */
1486 buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32;
1487 buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid;
1492 static void btrfs_kill_super(struct super_block *sb)
1494 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1495 kill_anon_super(sb);
1496 free_fs_info(fs_info);
1499 static struct file_system_type btrfs_fs_type = {
1500 .owner = THIS_MODULE,
1502 .mount = btrfs_mount,
1503 .kill_sb = btrfs_kill_super,
1504 .fs_flags = FS_REQUIRES_DEV,
1508 * used by btrfsctl to scan devices when no FS is mounted
1510 static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
1513 struct btrfs_ioctl_vol_args *vol;
1514 struct btrfs_fs_devices *fs_devices;
1517 if (!capable(CAP_SYS_ADMIN))
1520 vol = memdup_user((void __user *)arg, sizeof(*vol));
1522 return PTR_ERR(vol);
1525 case BTRFS_IOC_SCAN_DEV:
1526 ret = btrfs_scan_one_device(vol->name, FMODE_READ,
1527 &btrfs_fs_type, &fs_devices);
1529 case BTRFS_IOC_DEVICES_READY:
1530 ret = btrfs_scan_one_device(vol->name, FMODE_READ,
1531 &btrfs_fs_type, &fs_devices);
1534 ret = !(fs_devices->num_devices == fs_devices->total_devices);
1542 static int btrfs_freeze(struct super_block *sb)
1544 struct btrfs_trans_handle *trans;
1545 struct btrfs_root *root = btrfs_sb(sb)->tree_root;
1547 trans = btrfs_attach_transaction(root);
1548 if (IS_ERR(trans)) {
1549 /* no transaction, don't bother */
1550 if (PTR_ERR(trans) == -ENOENT)
1552 return PTR_ERR(trans);
1554 return btrfs_commit_transaction(trans, root);
1557 static int btrfs_unfreeze(struct super_block *sb)
1562 static int btrfs_show_devname(struct seq_file *m, struct dentry *root)
1564 struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb);
1565 struct btrfs_fs_devices *cur_devices;
1566 struct btrfs_device *dev, *first_dev = NULL;
1567 struct list_head *head;
1568 struct rcu_string *name;
1570 mutex_lock(&fs_info->fs_devices->device_list_mutex);
1571 cur_devices = fs_info->fs_devices;
1572 while (cur_devices) {
1573 head = &cur_devices->devices;
1574 list_for_each_entry(dev, head, dev_list) {
1577 if (!first_dev || dev->devid < first_dev->devid)
1580 cur_devices = cur_devices->seed;
1585 name = rcu_dereference(first_dev->name);
1586 seq_escape(m, name->str, " \t\n\\");
1591 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
1595 static const struct super_operations btrfs_super_ops = {
1596 .drop_inode = btrfs_drop_inode,
1597 .evict_inode = btrfs_evict_inode,
1598 .put_super = btrfs_put_super,
1599 .sync_fs = btrfs_sync_fs,
1600 .show_options = btrfs_show_options,
1601 .show_devname = btrfs_show_devname,
1602 .write_inode = btrfs_write_inode,
1603 .alloc_inode = btrfs_alloc_inode,
1604 .destroy_inode = btrfs_destroy_inode,
1605 .statfs = btrfs_statfs,
1606 .remount_fs = btrfs_remount,
1607 .freeze_fs = btrfs_freeze,
1608 .unfreeze_fs = btrfs_unfreeze,
1611 static const struct file_operations btrfs_ctl_fops = {
1612 .unlocked_ioctl = btrfs_control_ioctl,
1613 .compat_ioctl = btrfs_control_ioctl,
1614 .owner = THIS_MODULE,
1615 .llseek = noop_llseek,
1618 static struct miscdevice btrfs_misc = {
1619 .minor = BTRFS_MINOR,
1620 .name = "btrfs-control",
1621 .fops = &btrfs_ctl_fops
1624 MODULE_ALIAS_MISCDEV(BTRFS_MINOR);
1625 MODULE_ALIAS("devname:btrfs-control");
1627 static int btrfs_interface_init(void)
1629 return misc_register(&btrfs_misc);
1632 static void btrfs_interface_exit(void)
1634 if (misc_deregister(&btrfs_misc) < 0)
1635 printk(KERN_INFO "btrfs: misc_deregister failed for control device\n");
1638 static int __init init_btrfs_fs(void)
1642 err = btrfs_init_sysfs();
1646 btrfs_init_compress();
1648 err = btrfs_init_cachep();
1652 err = extent_io_init();
1656 err = extent_map_init();
1658 goto free_extent_io;
1660 err = ordered_data_init();
1662 goto free_extent_map;
1664 err = btrfs_delayed_inode_init();
1666 goto free_ordered_data;
1668 err = btrfs_interface_init();
1670 goto free_delayed_inode;
1672 err = register_filesystem(&btrfs_fs_type);
1674 goto unregister_ioctl;
1676 btrfs_init_lockdep();
1678 printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION);
1682 btrfs_interface_exit();
1684 btrfs_delayed_inode_exit();
1686 ordered_data_exit();
1692 btrfs_destroy_cachep();
1694 btrfs_exit_compress();
1699 static void __exit exit_btrfs_fs(void)
1701 btrfs_destroy_cachep();
1702 btrfs_delayed_inode_exit();
1703 ordered_data_exit();
1706 btrfs_interface_exit();
1707 unregister_filesystem(&btrfs_fs_type);
1709 btrfs_cleanup_fs_uuids();
1710 btrfs_exit_compress();
1713 module_init(init_btrfs_fs)
1714 module_exit(exit_btrfs_fs)
1716 MODULE_LICENSE("GPL");