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
;
104 * We move write_super stuff at umount in order to avoid deadlock
105 * for umount hold all lock.
107 static void save_error_info(struct btrfs_fs_info
*fs_info
)
109 __save_error_info(fs_info
);
112 /* btrfs handle error by forcing the filesystem readonly */
113 static void btrfs_handle_error(struct btrfs_fs_info
*fs_info
)
115 struct super_block
*sb
= fs_info
->sb
;
117 if (sb
->s_flags
& MS_RDONLY
)
120 if (fs_info
->fs_state
& BTRFS_SUPER_FLAG_ERROR
) {
121 sb
->s_flags
|= MS_RDONLY
;
122 printk(KERN_INFO
"btrfs is forced readonly\n");
123 __btrfs_scrub_cancel(fs_info
);
129 * __btrfs_std_error decodes expected errors from the caller and
130 * invokes the approciate error response.
132 void __btrfs_std_error(struct btrfs_fs_info
*fs_info
, const char *function
,
133 unsigned int line
, int errno
, const char *fmt
, ...)
135 struct super_block
*sb
= fs_info
->sb
;
142 * Special case: if the error is EROFS, and we're already
143 * under MS_RDONLY, then it is safe here.
145 if (errno
== -EROFS
&& (sb
->s_flags
& MS_RDONLY
))
148 errstr
= btrfs_decode_error(fs_info
, errno
, nbuf
);
150 struct va_format vaf
= {
155 printk(KERN_CRIT
"BTRFS error (device %s) in %s:%d: %s (%pV)\n",
156 sb
->s_id
, function
, line
, errstr
, &vaf
);
158 printk(KERN_CRIT
"BTRFS error (device %s) in %s:%d: %s\n",
159 sb
->s_id
, function
, line
, errstr
);
162 /* Don't go through full error handling during mount */
163 if (sb
->s_flags
& MS_BORN
) {
164 save_error_info(fs_info
);
165 btrfs_handle_error(fs_info
);
170 const char *logtypes
[] = {
181 void btrfs_printk(struct btrfs_fs_info
*fs_info
, const char *fmt
, ...)
183 struct super_block
*sb
= fs_info
->sb
;
185 struct va_format vaf
;
187 const char *type
= logtypes
[4];
191 if (fmt
[0] == '<' && isdigit(fmt
[1]) && fmt
[2] == '>') {
195 type
= logtypes
[fmt
[1] - '0'];
201 printk("%sBTRFS %s (device %s): %pV", lvl
, type
, sb
->s_id
, &vaf
);
205 * We only mark the transaction aborted and then set the file system read-only.
206 * This will prevent new transactions from starting or trying to join this
209 * This means that error recovery at the call site is limited to freeing
210 * any local memory allocations and passing the error code up without
211 * further cleanup. The transaction should complete as it normally would
212 * in the call path but will return -EIO.
214 * We'll complete the cleanup in btrfs_end_transaction and
215 * btrfs_commit_transaction.
217 void __btrfs_abort_transaction(struct btrfs_trans_handle
*trans
,
218 struct btrfs_root
*root
, const char *function
,
219 unsigned int line
, int errno
)
221 WARN_ONCE(1, KERN_DEBUG
"btrfs: Transaction aborted");
222 trans
->aborted
= errno
;
223 /* Nothing used. The other threads that have joined this
224 * transaction may be able to continue. */
225 if (!trans
->blocks_used
) {
226 btrfs_printk(root
->fs_info
, "Aborting unused transaction.\n");
229 trans
->transaction
->aborted
= errno
;
230 __btrfs_std_error(root
->fs_info
, function
, line
, errno
, NULL
);
233 * __btrfs_panic decodes unexpected, fatal errors from the caller,
234 * issues an alert, and either panics or BUGs, depending on mount options.
236 void __btrfs_panic(struct btrfs_fs_info
*fs_info
, const char *function
,
237 unsigned int line
, int errno
, const char *fmt
, ...)
240 char *s_id
= "<unknown>";
242 struct va_format vaf
= { .fmt
= fmt
};
246 s_id
= fs_info
->sb
->s_id
;
251 errstr
= btrfs_decode_error(fs_info
, errno
, nbuf
);
252 if (fs_info
->mount_opt
& BTRFS_MOUNT_PANIC_ON_FATAL_ERROR
)
253 panic(KERN_CRIT
"BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
254 s_id
, function
, line
, &vaf
, errstr
);
256 printk(KERN_CRIT
"BTRFS panic (device %s) in %s:%d: %pV (%s)\n",
257 s_id
, function
, line
, &vaf
, errstr
);
259 /* Caller calls BUG() */
262 static void btrfs_put_super(struct super_block
*sb
)
264 (void)close_ctree(btrfs_sb(sb
)->tree_root
);
265 /* FIXME: need to fix VFS to return error? */
266 /* AV: return it _where_? ->put_super() can be triggered by any number
267 * of async events, up to and including delivery of SIGKILL to the
268 * last process that kept it busy. Or segfault in the aforementioned
269 * process... Whom would you report that to?
274 Opt_degraded
, Opt_subvol
, Opt_subvolid
, Opt_device
, Opt_nodatasum
,
275 Opt_nodatacow
, Opt_max_inline
, Opt_alloc_start
, Opt_nobarrier
, Opt_ssd
,
276 Opt_nossd
, Opt_ssd_spread
, Opt_thread_pool
, Opt_noacl
, Opt_compress
,
277 Opt_compress_type
, Opt_compress_force
, Opt_compress_force_type
,
278 Opt_notreelog
, Opt_ratio
, Opt_flushoncommit
, Opt_discard
,
279 Opt_space_cache
, Opt_clear_cache
, Opt_user_subvol_rm_allowed
,
280 Opt_enospc_debug
, Opt_subvolrootid
, Opt_defrag
, Opt_inode_cache
,
281 Opt_no_space_cache
, Opt_recovery
, Opt_skip_balance
,
282 Opt_check_integrity
, Opt_check_integrity_including_extent_data
,
283 Opt_check_integrity_print_mask
, Opt_fatal_errors
,
287 static match_table_t tokens
= {
288 {Opt_degraded
, "degraded"},
289 {Opt_subvol
, "subvol=%s"},
290 {Opt_subvolid
, "subvolid=%d"},
291 {Opt_device
, "device=%s"},
292 {Opt_nodatasum
, "nodatasum"},
293 {Opt_nodatacow
, "nodatacow"},
294 {Opt_nobarrier
, "nobarrier"},
295 {Opt_max_inline
, "max_inline=%s"},
296 {Opt_alloc_start
, "alloc_start=%s"},
297 {Opt_thread_pool
, "thread_pool=%d"},
298 {Opt_compress
, "compress"},
299 {Opt_compress_type
, "compress=%s"},
300 {Opt_compress_force
, "compress-force"},
301 {Opt_compress_force_type
, "compress-force=%s"},
303 {Opt_ssd_spread
, "ssd_spread"},
304 {Opt_nossd
, "nossd"},
305 {Opt_noacl
, "noacl"},
306 {Opt_notreelog
, "notreelog"},
307 {Opt_flushoncommit
, "flushoncommit"},
308 {Opt_ratio
, "metadata_ratio=%d"},
309 {Opt_discard
, "discard"},
310 {Opt_space_cache
, "space_cache"},
311 {Opt_clear_cache
, "clear_cache"},
312 {Opt_user_subvol_rm_allowed
, "user_subvol_rm_allowed"},
313 {Opt_enospc_debug
, "enospc_debug"},
314 {Opt_subvolrootid
, "subvolrootid=%d"},
315 {Opt_defrag
, "autodefrag"},
316 {Opt_inode_cache
, "inode_cache"},
317 {Opt_no_space_cache
, "nospace_cache"},
318 {Opt_recovery
, "recovery"},
319 {Opt_skip_balance
, "skip_balance"},
320 {Opt_check_integrity
, "check_int"},
321 {Opt_check_integrity_including_extent_data
, "check_int_data"},
322 {Opt_check_integrity_print_mask
, "check_int_print_mask=%d"},
323 {Opt_fatal_errors
, "fatal_errors=%s"},
328 * Regular mount options parser. Everything that is needed only when
329 * reading in a new superblock is parsed here.
330 * XXX JDM: This needs to be cleaned up for remount.
332 int btrfs_parse_options(struct btrfs_root
*root
, char *options
)
334 struct btrfs_fs_info
*info
= root
->fs_info
;
335 substring_t args
[MAX_OPT_ARGS
];
336 char *p
, *num
, *orig
= NULL
;
341 bool compress_force
= false;
343 cache_gen
= btrfs_super_cache_generation(root
->fs_info
->super_copy
);
345 btrfs_set_opt(info
->mount_opt
, SPACE_CACHE
);
351 * strsep changes the string, duplicate it because parse_options
354 options
= kstrdup(options
, GFP_NOFS
);
360 while ((p
= strsep(&options
, ",")) != NULL
) {
365 token
= match_token(p
, tokens
, args
);
368 printk(KERN_INFO
"btrfs: allowing degraded mounts\n");
369 btrfs_set_opt(info
->mount_opt
, DEGRADED
);
373 case Opt_subvolrootid
:
376 * These are parsed by btrfs_parse_early_options
377 * and can be happily ignored here.
381 printk(KERN_INFO
"btrfs: setting nodatasum\n");
382 btrfs_set_opt(info
->mount_opt
, NODATASUM
);
385 printk(KERN_INFO
"btrfs: setting nodatacow\n");
386 btrfs_set_opt(info
->mount_opt
, NODATACOW
);
387 btrfs_set_opt(info
->mount_opt
, NODATASUM
);
389 case Opt_compress_force
:
390 case Opt_compress_force_type
:
391 compress_force
= true;
393 case Opt_compress_type
:
394 if (token
== Opt_compress
||
395 token
== Opt_compress_force
||
396 strcmp(args
[0].from
, "zlib") == 0) {
397 compress_type
= "zlib";
398 info
->compress_type
= BTRFS_COMPRESS_ZLIB
;
399 } else if (strcmp(args
[0].from
, "lzo") == 0) {
400 compress_type
= "lzo";
401 info
->compress_type
= BTRFS_COMPRESS_LZO
;
407 btrfs_set_opt(info
->mount_opt
, COMPRESS
);
408 if (compress_force
) {
409 btrfs_set_opt(info
->mount_opt
, FORCE_COMPRESS
);
410 pr_info("btrfs: force %s compression\n",
413 pr_info("btrfs: use %s compression\n",
417 printk(KERN_INFO
"btrfs: use ssd allocation scheme\n");
418 btrfs_set_opt(info
->mount_opt
, SSD
);
421 printk(KERN_INFO
"btrfs: use spread ssd "
422 "allocation scheme\n");
423 btrfs_set_opt(info
->mount_opt
, SSD
);
424 btrfs_set_opt(info
->mount_opt
, SSD_SPREAD
);
427 printk(KERN_INFO
"btrfs: not using ssd allocation "
429 btrfs_set_opt(info
->mount_opt
, NOSSD
);
430 btrfs_clear_opt(info
->mount_opt
, SSD
);
431 btrfs_clear_opt(info
->mount_opt
, SSD_SPREAD
);
434 printk(KERN_INFO
"btrfs: turning off barriers\n");
435 btrfs_set_opt(info
->mount_opt
, NOBARRIER
);
437 case Opt_thread_pool
:
439 match_int(&args
[0], &intarg
);
441 info
->thread_pool_size
= intarg
;
444 num
= match_strdup(&args
[0]);
446 info
->max_inline
= memparse(num
, NULL
);
449 if (info
->max_inline
) {
450 info
->max_inline
= max_t(u64
,
454 printk(KERN_INFO
"btrfs: max_inline at %llu\n",
455 (unsigned long long)info
->max_inline
);
458 case Opt_alloc_start
:
459 num
= match_strdup(&args
[0]);
461 info
->alloc_start
= memparse(num
, NULL
);
464 "btrfs: allocations start at %llu\n",
465 (unsigned long long)info
->alloc_start
);
469 root
->fs_info
->sb
->s_flags
&= ~MS_POSIXACL
;
472 printk(KERN_INFO
"btrfs: disabling tree log\n");
473 btrfs_set_opt(info
->mount_opt
, NOTREELOG
);
475 case Opt_flushoncommit
:
476 printk(KERN_INFO
"btrfs: turning on flush-on-commit\n");
477 btrfs_set_opt(info
->mount_opt
, FLUSHONCOMMIT
);
481 match_int(&args
[0], &intarg
);
483 info
->metadata_ratio
= intarg
;
484 printk(KERN_INFO
"btrfs: metadata ratio %d\n",
485 info
->metadata_ratio
);
489 btrfs_set_opt(info
->mount_opt
, DISCARD
);
491 case Opt_space_cache
:
492 btrfs_set_opt(info
->mount_opt
, SPACE_CACHE
);
494 case Opt_no_space_cache
:
495 printk(KERN_INFO
"btrfs: disabling disk space caching\n");
496 btrfs_clear_opt(info
->mount_opt
, SPACE_CACHE
);
498 case Opt_inode_cache
:
499 printk(KERN_INFO
"btrfs: enabling inode map caching\n");
500 btrfs_set_opt(info
->mount_opt
, INODE_MAP_CACHE
);
502 case Opt_clear_cache
:
503 printk(KERN_INFO
"btrfs: force clearing of disk cache\n");
504 btrfs_set_opt(info
->mount_opt
, CLEAR_CACHE
);
506 case Opt_user_subvol_rm_allowed
:
507 btrfs_set_opt(info
->mount_opt
, USER_SUBVOL_RM_ALLOWED
);
509 case Opt_enospc_debug
:
510 btrfs_set_opt(info
->mount_opt
, ENOSPC_DEBUG
);
513 printk(KERN_INFO
"btrfs: enabling auto defrag");
514 btrfs_set_opt(info
->mount_opt
, AUTO_DEFRAG
);
517 printk(KERN_INFO
"btrfs: enabling auto recovery");
518 btrfs_set_opt(info
->mount_opt
, RECOVERY
);
520 case Opt_skip_balance
:
521 btrfs_set_opt(info
->mount_opt
, SKIP_BALANCE
);
523 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
524 case Opt_check_integrity_including_extent_data
:
525 printk(KERN_INFO
"btrfs: enabling check integrity"
526 " including extent data\n");
527 btrfs_set_opt(info
->mount_opt
,
528 CHECK_INTEGRITY_INCLUDING_EXTENT_DATA
);
529 btrfs_set_opt(info
->mount_opt
, CHECK_INTEGRITY
);
531 case Opt_check_integrity
:
532 printk(KERN_INFO
"btrfs: enabling check integrity\n");
533 btrfs_set_opt(info
->mount_opt
, CHECK_INTEGRITY
);
535 case Opt_check_integrity_print_mask
:
537 match_int(&args
[0], &intarg
);
539 info
->check_integrity_print_mask
= intarg
;
540 printk(KERN_INFO
"btrfs:"
541 " check_integrity_print_mask 0x%x\n",
542 info
->check_integrity_print_mask
);
546 case Opt_check_integrity_including_extent_data
:
547 case Opt_check_integrity
:
548 case Opt_check_integrity_print_mask
:
549 printk(KERN_ERR
"btrfs: support for check_integrity*"
550 " not compiled in!\n");
554 case Opt_fatal_errors
:
555 if (strcmp(args
[0].from
, "panic") == 0)
556 btrfs_set_opt(info
->mount_opt
,
557 PANIC_ON_FATAL_ERROR
);
558 else if (strcmp(args
[0].from
, "bug") == 0)
559 btrfs_clear_opt(info
->mount_opt
,
560 PANIC_ON_FATAL_ERROR
);
567 printk(KERN_INFO
"btrfs: unrecognized mount option "
576 if (!ret
&& btrfs_test_opt(root
, SPACE_CACHE
))
577 printk(KERN_INFO
"btrfs: disk space caching is enabled\n");
583 * Parse mount options that are required early in the mount process.
585 * All other options will be parsed on much later in the mount process and
586 * only when we need to allocate a new super block.
588 static int btrfs_parse_early_options(const char *options
, fmode_t flags
,
589 void *holder
, char **subvol_name
, u64
*subvol_objectid
,
590 u64
*subvol_rootid
, struct btrfs_fs_devices
**fs_devices
)
592 substring_t args
[MAX_OPT_ARGS
];
593 char *device_name
, *opts
, *orig
, *p
;
601 * strsep changes the string, duplicate it because parse_options
604 opts
= kstrdup(options
, GFP_KERNEL
);
609 while ((p
= strsep(&opts
, ",")) != NULL
) {
614 token
= match_token(p
, tokens
, args
);
618 *subvol_name
= match_strdup(&args
[0]);
622 error
= match_int(&args
[0], &intarg
);
624 /* we want the original fs_tree */
627 BTRFS_FS_TREE_OBJECTID
;
629 *subvol_objectid
= intarg
;
632 case Opt_subvolrootid
:
634 error
= match_int(&args
[0], &intarg
);
636 /* we want the original fs_tree */
639 BTRFS_FS_TREE_OBJECTID
;
641 *subvol_rootid
= intarg
;
645 device_name
= match_strdup(&args
[0]);
650 error
= btrfs_scan_one_device(device_name
,
651 flags
, holder
, fs_devices
);
666 static struct dentry
*get_default_root(struct super_block
*sb
,
669 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
670 struct btrfs_root
*root
= fs_info
->tree_root
;
671 struct btrfs_root
*new_root
;
672 struct btrfs_dir_item
*di
;
673 struct btrfs_path
*path
;
674 struct btrfs_key location
;
680 * We have a specific subvol we want to mount, just setup location and
681 * go look up the root.
683 if (subvol_objectid
) {
684 location
.objectid
= subvol_objectid
;
685 location
.type
= BTRFS_ROOT_ITEM_KEY
;
686 location
.offset
= (u64
)-1;
690 path
= btrfs_alloc_path();
692 return ERR_PTR(-ENOMEM
);
693 path
->leave_spinning
= 1;
696 * Find the "default" dir item which points to the root item that we
697 * will mount by default if we haven't been given a specific subvolume
700 dir_id
= btrfs_super_root_dir(fs_info
->super_copy
);
701 di
= btrfs_lookup_dir_item(NULL
, root
, path
, dir_id
, "default", 7, 0);
703 btrfs_free_path(path
);
708 * Ok the default dir item isn't there. This is weird since
709 * it's always been there, but don't freak out, just try and
710 * mount to root most subvolume.
712 btrfs_free_path(path
);
713 dir_id
= BTRFS_FIRST_FREE_OBJECTID
;
714 new_root
= fs_info
->fs_root
;
718 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
719 btrfs_free_path(path
);
722 new_root
= btrfs_read_fs_root_no_name(fs_info
, &location
);
723 if (IS_ERR(new_root
))
724 return ERR_CAST(new_root
);
726 if (btrfs_root_refs(&new_root
->root_item
) == 0)
727 return ERR_PTR(-ENOENT
);
729 dir_id
= btrfs_root_dirid(&new_root
->root_item
);
731 location
.objectid
= dir_id
;
732 location
.type
= BTRFS_INODE_ITEM_KEY
;
735 inode
= btrfs_iget(sb
, &location
, new_root
, &new);
737 return ERR_CAST(inode
);
740 * If we're just mounting the root most subvol put the inode and return
741 * a reference to the dentry. We will have already gotten a reference
742 * to the inode in btrfs_fill_super so we're good to go.
744 if (!new && sb
->s_root
->d_inode
== inode
) {
746 return dget(sb
->s_root
);
749 return d_obtain_alias(inode
);
752 static int btrfs_fill_super(struct super_block
*sb
,
753 struct btrfs_fs_devices
*fs_devices
,
754 void *data
, int silent
)
757 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
758 struct btrfs_key key
;
761 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
762 sb
->s_magic
= BTRFS_SUPER_MAGIC
;
763 sb
->s_op
= &btrfs_super_ops
;
764 sb
->s_d_op
= &btrfs_dentry_operations
;
765 sb
->s_export_op
= &btrfs_export_ops
;
766 sb
->s_xattr
= btrfs_xattr_handlers
;
768 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
769 sb
->s_flags
|= MS_POSIXACL
;
771 sb
->s_flags
|= MS_I_VERSION
;
772 err
= open_ctree(sb
, fs_devices
, (char *)data
);
774 printk("btrfs: open_ctree failed\n");
778 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
779 key
.type
= BTRFS_INODE_ITEM_KEY
;
781 inode
= btrfs_iget(sb
, &key
, fs_info
->fs_root
, NULL
);
783 err
= PTR_ERR(inode
);
787 sb
->s_root
= d_make_root(inode
);
793 save_mount_options(sb
, data
);
794 cleancache_init_fs(sb
);
795 sb
->s_flags
|= MS_ACTIVE
;
799 close_ctree(fs_info
->tree_root
);
803 int btrfs_sync_fs(struct super_block
*sb
, int wait
)
805 struct btrfs_trans_handle
*trans
;
806 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
807 struct btrfs_root
*root
= fs_info
->tree_root
;
810 trace_btrfs_sync_fs(wait
);
813 filemap_flush(fs_info
->btree_inode
->i_mapping
);
817 btrfs_wait_ordered_extents(root
, 0, 0);
819 trans
= btrfs_start_transaction(root
, 0);
821 return PTR_ERR(trans
);
822 ret
= btrfs_commit_transaction(trans
, root
);
826 static int btrfs_show_options(struct seq_file
*seq
, struct dentry
*dentry
)
828 struct btrfs_fs_info
*info
= btrfs_sb(dentry
->d_sb
);
829 struct btrfs_root
*root
= info
->tree_root
;
832 if (btrfs_test_opt(root
, DEGRADED
))
833 seq_puts(seq
, ",degraded");
834 if (btrfs_test_opt(root
, NODATASUM
))
835 seq_puts(seq
, ",nodatasum");
836 if (btrfs_test_opt(root
, NODATACOW
))
837 seq_puts(seq
, ",nodatacow");
838 if (btrfs_test_opt(root
, NOBARRIER
))
839 seq_puts(seq
, ",nobarrier");
840 if (info
->max_inline
!= 8192 * 1024)
841 seq_printf(seq
, ",max_inline=%llu",
842 (unsigned long long)info
->max_inline
);
843 if (info
->alloc_start
!= 0)
844 seq_printf(seq
, ",alloc_start=%llu",
845 (unsigned long long)info
->alloc_start
);
846 if (info
->thread_pool_size
!= min_t(unsigned long,
847 num_online_cpus() + 2, 8))
848 seq_printf(seq
, ",thread_pool=%d", info
->thread_pool_size
);
849 if (btrfs_test_opt(root
, COMPRESS
)) {
850 if (info
->compress_type
== BTRFS_COMPRESS_ZLIB
)
851 compress_type
= "zlib";
853 compress_type
= "lzo";
854 if (btrfs_test_opt(root
, FORCE_COMPRESS
))
855 seq_printf(seq
, ",compress-force=%s", compress_type
);
857 seq_printf(seq
, ",compress=%s", compress_type
);
859 if (btrfs_test_opt(root
, NOSSD
))
860 seq_puts(seq
, ",nossd");
861 if (btrfs_test_opt(root
, SSD_SPREAD
))
862 seq_puts(seq
, ",ssd_spread");
863 else if (btrfs_test_opt(root
, SSD
))
864 seq_puts(seq
, ",ssd");
865 if (btrfs_test_opt(root
, NOTREELOG
))
866 seq_puts(seq
, ",notreelog");
867 if (btrfs_test_opt(root
, FLUSHONCOMMIT
))
868 seq_puts(seq
, ",flushoncommit");
869 if (btrfs_test_opt(root
, DISCARD
))
870 seq_puts(seq
, ",discard");
871 if (!(root
->fs_info
->sb
->s_flags
& MS_POSIXACL
))
872 seq_puts(seq
, ",noacl");
873 if (btrfs_test_opt(root
, SPACE_CACHE
))
874 seq_puts(seq
, ",space_cache");
876 seq_puts(seq
, ",nospace_cache");
877 if (btrfs_test_opt(root
, CLEAR_CACHE
))
878 seq_puts(seq
, ",clear_cache");
879 if (btrfs_test_opt(root
, USER_SUBVOL_RM_ALLOWED
))
880 seq_puts(seq
, ",user_subvol_rm_allowed");
881 if (btrfs_test_opt(root
, ENOSPC_DEBUG
))
882 seq_puts(seq
, ",enospc_debug");
883 if (btrfs_test_opt(root
, AUTO_DEFRAG
))
884 seq_puts(seq
, ",autodefrag");
885 if (btrfs_test_opt(root
, INODE_MAP_CACHE
))
886 seq_puts(seq
, ",inode_cache");
887 if (btrfs_test_opt(root
, SKIP_BALANCE
))
888 seq_puts(seq
, ",skip_balance");
889 if (btrfs_test_opt(root
, PANIC_ON_FATAL_ERROR
))
890 seq_puts(seq
, ",fatal_errors=panic");
894 static int btrfs_test_super(struct super_block
*s
, void *data
)
896 struct btrfs_fs_info
*p
= data
;
897 struct btrfs_fs_info
*fs_info
= btrfs_sb(s
);
899 return fs_info
->fs_devices
== p
->fs_devices
;
902 static int btrfs_set_super(struct super_block
*s
, void *data
)
904 int err
= set_anon_super(s
, data
);
911 * subvolumes are identified by ino 256
913 static inline int is_subvolume_inode(struct inode
*inode
)
915 if (inode
&& inode
->i_ino
== BTRFS_FIRST_FREE_OBJECTID
)
921 * This will strip out the subvol=%s argument for an argument string and add
922 * subvolid=0 to make sure we get the actual tree root for path walking to the
925 static char *setup_root_args(char *args
)
927 unsigned len
= strlen(args
) + 2 + 1;
928 char *src
, *dst
, *buf
;
931 * We need the same args as before, but with this substitution:
932 * s!subvol=[^,]+!subvolid=0!
934 * Since the replacement string is up to 2 bytes longer than the
935 * original, allocate strlen(args) + 2 + 1 bytes.
938 src
= strstr(args
, "subvol=");
939 /* This shouldn't happen, but just in case.. */
943 buf
= dst
= kmalloc(len
, GFP_NOFS
);
948 * If the subvol= arg is not at the start of the string,
949 * copy whatever precedes it into buf.
957 strcpy(dst
, "subvolid=0");
958 dst
+= strlen("subvolid=0");
961 * If there is a "," after the original subvol=... string,
962 * copy that suffix into our buffer. Otherwise, we're done.
964 src
= strchr(src
, ',');
971 static struct dentry
*mount_subvol(const char *subvol_name
, int flags
,
972 const char *device_name
, char *data
)
975 struct vfsmount
*mnt
;
978 newargs
= setup_root_args(data
);
980 return ERR_PTR(-ENOMEM
);
981 mnt
= vfs_kern_mount(&btrfs_fs_type
, flags
, device_name
,
985 return ERR_CAST(mnt
);
987 root
= mount_subtree(mnt
, subvol_name
);
989 if (!IS_ERR(root
) && !is_subvolume_inode(root
->d_inode
)) {
990 struct super_block
*s
= root
->d_sb
;
992 root
= ERR_PTR(-EINVAL
);
993 deactivate_locked_super(s
);
994 printk(KERN_ERR
"btrfs: '%s' is not a valid subvolume\n",
1002 * Find a superblock for the given device / mount point.
1004 * Note: This is based on get_sb_bdev from fs/super.c with a few additions
1005 * for multiple device setup. Make sure to keep it in sync.
1007 static struct dentry
*btrfs_mount(struct file_system_type
*fs_type
, int flags
,
1008 const char *device_name
, void *data
)
1010 struct block_device
*bdev
= NULL
;
1011 struct super_block
*s
;
1012 struct dentry
*root
;
1013 struct btrfs_fs_devices
*fs_devices
= NULL
;
1014 struct btrfs_fs_info
*fs_info
= NULL
;
1015 fmode_t mode
= FMODE_READ
;
1016 char *subvol_name
= NULL
;
1017 u64 subvol_objectid
= 0;
1018 u64 subvol_rootid
= 0;
1021 if (!(flags
& MS_RDONLY
))
1022 mode
|= FMODE_WRITE
;
1024 error
= btrfs_parse_early_options(data
, mode
, fs_type
,
1025 &subvol_name
, &subvol_objectid
,
1026 &subvol_rootid
, &fs_devices
);
1029 return ERR_PTR(error
);
1033 root
= mount_subvol(subvol_name
, flags
, device_name
, data
);
1038 error
= btrfs_scan_one_device(device_name
, mode
, fs_type
, &fs_devices
);
1040 return ERR_PTR(error
);
1043 * Setup a dummy root and fs_info for test/set super. This is because
1044 * we don't actually fill this stuff out until open_ctree, but we need
1045 * it for searching for existing supers, so this lets us do that and
1046 * then open_ctree will properly initialize everything later.
1048 fs_info
= kzalloc(sizeof(struct btrfs_fs_info
), GFP_NOFS
);
1050 return ERR_PTR(-ENOMEM
);
1052 fs_info
->fs_devices
= fs_devices
;
1054 fs_info
->super_copy
= kzalloc(BTRFS_SUPER_INFO_SIZE
, GFP_NOFS
);
1055 fs_info
->super_for_commit
= kzalloc(BTRFS_SUPER_INFO_SIZE
, GFP_NOFS
);
1056 if (!fs_info
->super_copy
|| !fs_info
->super_for_commit
) {
1061 error
= btrfs_open_devices(fs_devices
, mode
, fs_type
);
1065 if (!(flags
& MS_RDONLY
) && fs_devices
->rw_devices
== 0) {
1067 goto error_close_devices
;
1070 bdev
= fs_devices
->latest_bdev
;
1071 s
= sget(fs_type
, btrfs_test_super
, btrfs_set_super
, fs_info
);
1074 goto error_close_devices
;
1078 btrfs_close_devices(fs_devices
);
1079 free_fs_info(fs_info
);
1080 if ((flags
^ s
->s_flags
) & MS_RDONLY
)
1083 char b
[BDEVNAME_SIZE
];
1085 s
->s_flags
= flags
| MS_NOSEC
;
1086 strlcpy(s
->s_id
, bdevname(bdev
, b
), sizeof(s
->s_id
));
1087 btrfs_sb(s
)->bdev_holder
= fs_type
;
1088 error
= btrfs_fill_super(s
, fs_devices
, data
,
1089 flags
& MS_SILENT
? 1 : 0);
1092 root
= !error
? get_default_root(s
, subvol_objectid
) : ERR_PTR(error
);
1094 deactivate_locked_super(s
);
1098 error_close_devices
:
1099 btrfs_close_devices(fs_devices
);
1101 free_fs_info(fs_info
);
1102 return ERR_PTR(error
);
1105 static void btrfs_set_max_workers(struct btrfs_workers
*workers
, int new_limit
)
1107 spin_lock_irq(&workers
->lock
);
1108 workers
->max_workers
= new_limit
;
1109 spin_unlock_irq(&workers
->lock
);
1112 static void btrfs_resize_thread_pool(struct btrfs_fs_info
*fs_info
,
1113 int new_pool_size
, int old_pool_size
)
1115 if (new_pool_size
== old_pool_size
)
1118 fs_info
->thread_pool_size
= new_pool_size
;
1120 printk(KERN_INFO
"btrfs: resize thread pool %d -> %d\n",
1121 old_pool_size
, new_pool_size
);
1123 btrfs_set_max_workers(&fs_info
->generic_worker
, new_pool_size
);
1124 btrfs_set_max_workers(&fs_info
->workers
, new_pool_size
);
1125 btrfs_set_max_workers(&fs_info
->delalloc_workers
, new_pool_size
);
1126 btrfs_set_max_workers(&fs_info
->submit_workers
, new_pool_size
);
1127 btrfs_set_max_workers(&fs_info
->caching_workers
, new_pool_size
);
1128 btrfs_set_max_workers(&fs_info
->fixup_workers
, new_pool_size
);
1129 btrfs_set_max_workers(&fs_info
->endio_workers
, new_pool_size
);
1130 btrfs_set_max_workers(&fs_info
->endio_meta_workers
, new_pool_size
);
1131 btrfs_set_max_workers(&fs_info
->endio_meta_write_workers
, new_pool_size
);
1132 btrfs_set_max_workers(&fs_info
->endio_write_workers
, new_pool_size
);
1133 btrfs_set_max_workers(&fs_info
->endio_freespace_worker
, new_pool_size
);
1134 btrfs_set_max_workers(&fs_info
->delayed_workers
, new_pool_size
);
1135 btrfs_set_max_workers(&fs_info
->readahead_workers
, new_pool_size
);
1136 btrfs_set_max_workers(&fs_info
->scrub_workers
, new_pool_size
);
1139 static int btrfs_remount(struct super_block
*sb
, int *flags
, char *data
)
1141 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
1142 struct btrfs_root
*root
= fs_info
->tree_root
;
1143 unsigned old_flags
= sb
->s_flags
;
1144 unsigned long old_opts
= fs_info
->mount_opt
;
1145 unsigned long old_compress_type
= fs_info
->compress_type
;
1146 u64 old_max_inline
= fs_info
->max_inline
;
1147 u64 old_alloc_start
= fs_info
->alloc_start
;
1148 int old_thread_pool_size
= fs_info
->thread_pool_size
;
1149 unsigned int old_metadata_ratio
= fs_info
->metadata_ratio
;
1152 ret
= btrfs_parse_options(root
, data
);
1158 btrfs_resize_thread_pool(fs_info
,
1159 fs_info
->thread_pool_size
, old_thread_pool_size
);
1161 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
1164 if (*flags
& MS_RDONLY
) {
1165 sb
->s_flags
|= MS_RDONLY
;
1167 ret
= btrfs_commit_super(root
);
1171 if (fs_info
->fs_devices
->rw_devices
== 0) {
1176 if (btrfs_super_log_root(fs_info
->super_copy
) != 0) {
1181 ret
= btrfs_cleanup_fs_roots(fs_info
);
1185 /* recover relocation */
1186 ret
= btrfs_recover_relocation(root
);
1190 ret
= btrfs_resume_balance_async(fs_info
);
1194 sb
->s_flags
&= ~MS_RDONLY
;
1200 /* We've hit an error - don't reset MS_RDONLY */
1201 if (sb
->s_flags
& MS_RDONLY
)
1202 old_flags
|= MS_RDONLY
;
1203 sb
->s_flags
= old_flags
;
1204 fs_info
->mount_opt
= old_opts
;
1205 fs_info
->compress_type
= old_compress_type
;
1206 fs_info
->max_inline
= old_max_inline
;
1207 fs_info
->alloc_start
= old_alloc_start
;
1208 btrfs_resize_thread_pool(fs_info
,
1209 old_thread_pool_size
, fs_info
->thread_pool_size
);
1210 fs_info
->metadata_ratio
= old_metadata_ratio
;
1214 /* Used to sort the devices by max_avail(descending sort) */
1215 static int btrfs_cmp_device_free_bytes(const void *dev_info1
,
1216 const void *dev_info2
)
1218 if (((struct btrfs_device_info
*)dev_info1
)->max_avail
>
1219 ((struct btrfs_device_info
*)dev_info2
)->max_avail
)
1221 else if (((struct btrfs_device_info
*)dev_info1
)->max_avail
<
1222 ((struct btrfs_device_info
*)dev_info2
)->max_avail
)
1229 * sort the devices by max_avail, in which max free extent size of each device
1230 * is stored.(Descending Sort)
1232 static inline void btrfs_descending_sort_devices(
1233 struct btrfs_device_info
*devices
,
1236 sort(devices
, nr_devices
, sizeof(struct btrfs_device_info
),
1237 btrfs_cmp_device_free_bytes
, NULL
);
1241 * The helper to calc the free space on the devices that can be used to store
1244 static int btrfs_calc_avail_data_space(struct btrfs_root
*root
, u64
*free_bytes
)
1246 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1247 struct btrfs_device_info
*devices_info
;
1248 struct btrfs_fs_devices
*fs_devices
= fs_info
->fs_devices
;
1249 struct btrfs_device
*device
;
1254 u64 min_stripe_size
;
1255 int min_stripes
= 1, num_stripes
= 1;
1256 int i
= 0, nr_devices
;
1259 nr_devices
= fs_info
->fs_devices
->open_devices
;
1260 BUG_ON(!nr_devices
);
1262 devices_info
= kmalloc(sizeof(*devices_info
) * nr_devices
,
1267 /* calc min stripe number for data space alloction */
1268 type
= btrfs_get_alloc_profile(root
, 1);
1269 if (type
& BTRFS_BLOCK_GROUP_RAID0
) {
1271 num_stripes
= nr_devices
;
1272 } else if (type
& BTRFS_BLOCK_GROUP_RAID1
) {
1275 } else if (type
& BTRFS_BLOCK_GROUP_RAID10
) {
1280 if (type
& BTRFS_BLOCK_GROUP_DUP
)
1281 min_stripe_size
= 2 * BTRFS_STRIPE_LEN
;
1283 min_stripe_size
= BTRFS_STRIPE_LEN
;
1285 list_for_each_entry(device
, &fs_devices
->devices
, dev_list
) {
1286 if (!device
->in_fs_metadata
|| !device
->bdev
)
1289 avail_space
= device
->total_bytes
- device
->bytes_used
;
1291 /* align with stripe_len */
1292 do_div(avail_space
, BTRFS_STRIPE_LEN
);
1293 avail_space
*= BTRFS_STRIPE_LEN
;
1296 * In order to avoid overwritting the superblock on the drive,
1297 * btrfs starts at an offset of at least 1MB when doing chunk
1300 skip_space
= 1024 * 1024;
1302 /* user can set the offset in fs_info->alloc_start. */
1303 if (fs_info
->alloc_start
+ BTRFS_STRIPE_LEN
<=
1304 device
->total_bytes
)
1305 skip_space
= max(fs_info
->alloc_start
, skip_space
);
1308 * btrfs can not use the free space in [0, skip_space - 1],
1309 * we must subtract it from the total. In order to implement
1310 * it, we account the used space in this range first.
1312 ret
= btrfs_account_dev_extents_size(device
, 0, skip_space
- 1,
1315 kfree(devices_info
);
1319 /* calc the free space in [0, skip_space - 1] */
1320 skip_space
-= used_space
;
1323 * we can use the free space in [0, skip_space - 1], subtract
1324 * it from the total.
1326 if (avail_space
&& avail_space
>= skip_space
)
1327 avail_space
-= skip_space
;
1331 if (avail_space
< min_stripe_size
)
1334 devices_info
[i
].dev
= device
;
1335 devices_info
[i
].max_avail
= avail_space
;
1342 btrfs_descending_sort_devices(devices_info
, nr_devices
);
1346 while (nr_devices
>= min_stripes
) {
1347 if (num_stripes
> nr_devices
)
1348 num_stripes
= nr_devices
;
1350 if (devices_info
[i
].max_avail
>= min_stripe_size
) {
1354 avail_space
+= devices_info
[i
].max_avail
* num_stripes
;
1355 alloc_size
= devices_info
[i
].max_avail
;
1356 for (j
= i
+ 1 - num_stripes
; j
<= i
; j
++)
1357 devices_info
[j
].max_avail
-= alloc_size
;
1363 kfree(devices_info
);
1364 *free_bytes
= avail_space
;
1368 static int btrfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
1370 struct btrfs_fs_info
*fs_info
= btrfs_sb(dentry
->d_sb
);
1371 struct btrfs_super_block
*disk_super
= fs_info
->super_copy
;
1372 struct list_head
*head
= &fs_info
->space_info
;
1373 struct btrfs_space_info
*found
;
1375 u64 total_free_data
= 0;
1376 int bits
= dentry
->d_sb
->s_blocksize_bits
;
1377 __be32
*fsid
= (__be32
*)fs_info
->fsid
;
1380 /* holding chunk_muext to avoid allocating new chunks */
1381 mutex_lock(&fs_info
->chunk_mutex
);
1383 list_for_each_entry_rcu(found
, head
, list
) {
1384 if (found
->flags
& BTRFS_BLOCK_GROUP_DATA
) {
1385 total_free_data
+= found
->disk_total
- found
->disk_used
;
1387 btrfs_account_ro_block_groups_free_space(found
);
1390 total_used
+= found
->disk_used
;
1394 buf
->f_namelen
= BTRFS_NAME_LEN
;
1395 buf
->f_blocks
= btrfs_super_total_bytes(disk_super
) >> bits
;
1396 buf
->f_bfree
= buf
->f_blocks
- (total_used
>> bits
);
1397 buf
->f_bsize
= dentry
->d_sb
->s_blocksize
;
1398 buf
->f_type
= BTRFS_SUPER_MAGIC
;
1399 buf
->f_bavail
= total_free_data
;
1400 ret
= btrfs_calc_avail_data_space(fs_info
->tree_root
, &total_free_data
);
1402 mutex_unlock(&fs_info
->chunk_mutex
);
1405 buf
->f_bavail
+= total_free_data
;
1406 buf
->f_bavail
= buf
->f_bavail
>> bits
;
1407 mutex_unlock(&fs_info
->chunk_mutex
);
1409 /* We treat it as constant endianness (it doesn't matter _which_)
1410 because we want the fsid to come out the same whether mounted
1411 on a big-endian or little-endian host */
1412 buf
->f_fsid
.val
[0] = be32_to_cpu(fsid
[0]) ^ be32_to_cpu(fsid
[2]);
1413 buf
->f_fsid
.val
[1] = be32_to_cpu(fsid
[1]) ^ be32_to_cpu(fsid
[3]);
1414 /* Mask in the root object ID too, to disambiguate subvols */
1415 buf
->f_fsid
.val
[0] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
>> 32;
1416 buf
->f_fsid
.val
[1] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
;
1421 static void btrfs_kill_super(struct super_block
*sb
)
1423 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
1424 kill_anon_super(sb
);
1425 free_fs_info(fs_info
);
1428 static struct file_system_type btrfs_fs_type
= {
1429 .owner
= THIS_MODULE
,
1431 .mount
= btrfs_mount
,
1432 .kill_sb
= btrfs_kill_super
,
1433 .fs_flags
= FS_REQUIRES_DEV
,
1437 * used by btrfsctl to scan devices when no FS is mounted
1439 static long btrfs_control_ioctl(struct file
*file
, unsigned int cmd
,
1442 struct btrfs_ioctl_vol_args
*vol
;
1443 struct btrfs_fs_devices
*fs_devices
;
1446 if (!capable(CAP_SYS_ADMIN
))
1449 vol
= memdup_user((void __user
*)arg
, sizeof(*vol
));
1451 return PTR_ERR(vol
);
1454 case BTRFS_IOC_SCAN_DEV
:
1455 ret
= btrfs_scan_one_device(vol
->name
, FMODE_READ
,
1456 &btrfs_fs_type
, &fs_devices
);
1464 static int btrfs_freeze(struct super_block
*sb
)
1466 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
1467 mutex_lock(&fs_info
->transaction_kthread_mutex
);
1468 mutex_lock(&fs_info
->cleaner_mutex
);
1472 static int btrfs_unfreeze(struct super_block
*sb
)
1474 struct btrfs_fs_info
*fs_info
= btrfs_sb(sb
);
1475 mutex_unlock(&fs_info
->cleaner_mutex
);
1476 mutex_unlock(&fs_info
->transaction_kthread_mutex
);
1480 static void btrfs_fs_dirty_inode(struct inode
*inode
, int flags
)
1484 ret
= btrfs_dirty_inode(inode
);
1486 printk_ratelimited(KERN_ERR
"btrfs: fail to dirty inode %Lu "
1487 "error %d\n", btrfs_ino(inode
), ret
);
1490 static int btrfs_show_devname(struct seq_file
*m
, struct dentry
*root
)
1492 struct btrfs_fs_info
*fs_info
= btrfs_sb(root
->d_sb
);
1493 struct btrfs_fs_devices
*cur_devices
;
1494 struct btrfs_device
*dev
, *first_dev
= NULL
;
1495 struct list_head
*head
;
1496 struct rcu_string
*name
;
1498 mutex_lock(&fs_info
->fs_devices
->device_list_mutex
);
1499 cur_devices
= fs_info
->fs_devices
;
1500 while (cur_devices
) {
1501 head
= &cur_devices
->devices
;
1502 list_for_each_entry(dev
, head
, dev_list
) {
1503 if (!first_dev
|| dev
->devid
< first_dev
->devid
)
1506 cur_devices
= cur_devices
->seed
;
1511 name
= rcu_dereference(first_dev
->name
);
1512 seq_escape(m
, name
->str
, " \t\n\\");
1517 mutex_unlock(&fs_info
->fs_devices
->device_list_mutex
);
1521 static const struct super_operations btrfs_super_ops
= {
1522 .drop_inode
= btrfs_drop_inode
,
1523 .evict_inode
= btrfs_evict_inode
,
1524 .put_super
= btrfs_put_super
,
1525 .sync_fs
= btrfs_sync_fs
,
1526 .show_options
= btrfs_show_options
,
1527 .show_devname
= btrfs_show_devname
,
1528 .write_inode
= btrfs_write_inode
,
1529 .dirty_inode
= btrfs_fs_dirty_inode
,
1530 .alloc_inode
= btrfs_alloc_inode
,
1531 .destroy_inode
= btrfs_destroy_inode
,
1532 .statfs
= btrfs_statfs
,
1533 .remount_fs
= btrfs_remount
,
1534 .freeze_fs
= btrfs_freeze
,
1535 .unfreeze_fs
= btrfs_unfreeze
,
1538 static const struct file_operations btrfs_ctl_fops
= {
1539 .unlocked_ioctl
= btrfs_control_ioctl
,
1540 .compat_ioctl
= btrfs_control_ioctl
,
1541 .owner
= THIS_MODULE
,
1542 .llseek
= noop_llseek
,
1545 static struct miscdevice btrfs_misc
= {
1546 .minor
= BTRFS_MINOR
,
1547 .name
= "btrfs-control",
1548 .fops
= &btrfs_ctl_fops
1551 MODULE_ALIAS_MISCDEV(BTRFS_MINOR
);
1552 MODULE_ALIAS("devname:btrfs-control");
1554 static int btrfs_interface_init(void)
1556 return misc_register(&btrfs_misc
);
1559 static void btrfs_interface_exit(void)
1561 if (misc_deregister(&btrfs_misc
) < 0)
1562 printk(KERN_INFO
"misc_deregister failed for control device");
1565 static int __init
init_btrfs_fs(void)
1569 err
= btrfs_init_sysfs();
1573 btrfs_init_compress();
1575 err
= btrfs_init_cachep();
1579 err
= extent_io_init();
1583 err
= extent_map_init();
1585 goto free_extent_io
;
1587 err
= btrfs_delayed_inode_init();
1589 goto free_extent_map
;
1591 err
= btrfs_interface_init();
1593 goto free_delayed_inode
;
1595 err
= register_filesystem(&btrfs_fs_type
);
1597 goto unregister_ioctl
;
1599 btrfs_init_lockdep();
1601 printk(KERN_INFO
"%s loaded\n", BTRFS_BUILD_VERSION
);
1605 btrfs_interface_exit();
1607 btrfs_delayed_inode_exit();
1613 btrfs_destroy_cachep();
1615 btrfs_exit_compress();
1620 static void __exit
exit_btrfs_fs(void)
1622 btrfs_destroy_cachep();
1623 btrfs_delayed_inode_exit();
1626 btrfs_interface_exit();
1627 unregister_filesystem(&btrfs_fs_type
);
1629 btrfs_cleanup_fs_uuids();
1630 btrfs_exit_compress();
1633 module_init(init_btrfs_fs
)
1634 module_exit(exit_btrfs_fs
)
1636 MODULE_LICENSE("GPL");