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>
45 #include "transaction.h"
46 #include "btrfs_inode.h"
48 #include "print-tree.h"
53 #include "compression.h"
55 static const struct super_operations btrfs_super_ops
;
57 static void btrfs_put_super(struct super_block
*sb
)
59 struct btrfs_root
*root
= btrfs_sb(sb
);
62 ret
= close_ctree(root
);
67 Opt_degraded
, Opt_subvol
, Opt_subvolid
, Opt_device
, Opt_nodatasum
,
68 Opt_nodatacow
, Opt_max_inline
, Opt_alloc_start
, Opt_nobarrier
, Opt_ssd
,
69 Opt_nossd
, Opt_ssd_spread
, Opt_thread_pool
, Opt_noacl
, Opt_compress
,
70 Opt_compress_force
, Opt_notreelog
, Opt_ratio
, Opt_flushoncommit
,
71 Opt_discard
, Opt_space_cache
, Opt_err
,
74 static match_table_t tokens
= {
75 {Opt_degraded
, "degraded"},
76 {Opt_subvol
, "subvol=%s"},
77 {Opt_subvolid
, "subvolid=%d"},
78 {Opt_device
, "device=%s"},
79 {Opt_nodatasum
, "nodatasum"},
80 {Opt_nodatacow
, "nodatacow"},
81 {Opt_nobarrier
, "nobarrier"},
82 {Opt_max_inline
, "max_inline=%s"},
83 {Opt_alloc_start
, "alloc_start=%s"},
84 {Opt_thread_pool
, "thread_pool=%d"},
85 {Opt_compress
, "compress"},
86 {Opt_compress_force
, "compress-force"},
88 {Opt_ssd_spread
, "ssd_spread"},
91 {Opt_notreelog
, "notreelog"},
92 {Opt_flushoncommit
, "flushoncommit"},
93 {Opt_ratio
, "metadata_ratio=%d"},
94 {Opt_discard
, "discard"},
95 {Opt_space_cache
, "space_cache"},
100 * Regular mount options parser. Everything that is needed only when
101 * reading in a new superblock is parsed here.
103 int btrfs_parse_options(struct btrfs_root
*root
, char *options
)
105 struct btrfs_fs_info
*info
= root
->fs_info
;
106 substring_t args
[MAX_OPT_ARGS
];
107 char *p
, *num
, *orig
;
115 * strsep changes the string, duplicate it because parse_options
118 options
= kstrdup(options
, GFP_NOFS
);
124 while ((p
= strsep(&options
, ",")) != NULL
) {
129 token
= match_token(p
, tokens
, args
);
132 printk(KERN_INFO
"btrfs: allowing degraded mounts\n");
133 btrfs_set_opt(info
->mount_opt
, DEGRADED
);
139 * These are parsed by btrfs_parse_early_options
140 * and can be happily ignored here.
144 printk(KERN_INFO
"btrfs: setting nodatasum\n");
145 btrfs_set_opt(info
->mount_opt
, NODATASUM
);
148 printk(KERN_INFO
"btrfs: setting nodatacow\n");
149 btrfs_set_opt(info
->mount_opt
, NODATACOW
);
150 btrfs_set_opt(info
->mount_opt
, NODATASUM
);
153 printk(KERN_INFO
"btrfs: use compression\n");
154 btrfs_set_opt(info
->mount_opt
, COMPRESS
);
156 case Opt_compress_force
:
157 printk(KERN_INFO
"btrfs: forcing compression\n");
158 btrfs_set_opt(info
->mount_opt
, FORCE_COMPRESS
);
159 btrfs_set_opt(info
->mount_opt
, COMPRESS
);
162 printk(KERN_INFO
"btrfs: use ssd allocation scheme\n");
163 btrfs_set_opt(info
->mount_opt
, SSD
);
166 printk(KERN_INFO
"btrfs: use spread ssd "
167 "allocation scheme\n");
168 btrfs_set_opt(info
->mount_opt
, SSD
);
169 btrfs_set_opt(info
->mount_opt
, SSD_SPREAD
);
172 printk(KERN_INFO
"btrfs: not using ssd allocation "
174 btrfs_set_opt(info
->mount_opt
, NOSSD
);
175 btrfs_clear_opt(info
->mount_opt
, SSD
);
176 btrfs_clear_opt(info
->mount_opt
, SSD_SPREAD
);
179 printk(KERN_INFO
"btrfs: turning off barriers\n");
180 btrfs_set_opt(info
->mount_opt
, NOBARRIER
);
182 case Opt_thread_pool
:
184 match_int(&args
[0], &intarg
);
186 info
->thread_pool_size
= intarg
;
187 printk(KERN_INFO
"btrfs: thread pool %d\n",
188 info
->thread_pool_size
);
192 num
= match_strdup(&args
[0]);
194 info
->max_inline
= memparse(num
, NULL
);
197 if (info
->max_inline
) {
198 info
->max_inline
= max_t(u64
,
202 printk(KERN_INFO
"btrfs: max_inline at %llu\n",
203 (unsigned long long)info
->max_inline
);
206 case Opt_alloc_start
:
207 num
= match_strdup(&args
[0]);
209 info
->alloc_start
= memparse(num
, NULL
);
212 "btrfs: allocations start at %llu\n",
213 (unsigned long long)info
->alloc_start
);
217 root
->fs_info
->sb
->s_flags
&= ~MS_POSIXACL
;
220 printk(KERN_INFO
"btrfs: disabling tree log\n");
221 btrfs_set_opt(info
->mount_opt
, NOTREELOG
);
223 case Opt_flushoncommit
:
224 printk(KERN_INFO
"btrfs: turning on flush-on-commit\n");
225 btrfs_set_opt(info
->mount_opt
, FLUSHONCOMMIT
);
229 match_int(&args
[0], &intarg
);
231 info
->metadata_ratio
= intarg
;
232 printk(KERN_INFO
"btrfs: metadata ratio %d\n",
233 info
->metadata_ratio
);
237 btrfs_set_opt(info
->mount_opt
, DISCARD
);
239 case Opt_space_cache
:
240 printk(KERN_INFO
"btrfs: enabling disk space caching\n");
241 btrfs_set_opt(info
->mount_opt
, SPACE_CACHE
);
244 printk(KERN_INFO
"btrfs: unrecognized mount option "
258 * Parse mount options that are required early in the mount process.
260 * All other options will be parsed on much later in the mount process and
261 * only when we need to allocate a new super block.
263 static int btrfs_parse_early_options(const char *options
, fmode_t flags
,
264 void *holder
, char **subvol_name
, u64
*subvol_objectid
,
265 struct btrfs_fs_devices
**fs_devices
)
267 substring_t args
[MAX_OPT_ARGS
];
276 * strsep changes the string, duplicate it because parse_options
279 opts
= kstrdup(options
, GFP_KERNEL
);
283 while ((p
= strsep(&opts
, ",")) != NULL
) {
288 token
= match_token(p
, tokens
, args
);
291 *subvol_name
= match_strdup(&args
[0]);
295 error
= match_int(&args
[0], &intarg
);
297 /* we want the original fs_tree */
300 BTRFS_FS_TREE_OBJECTID
;
302 *subvol_objectid
= intarg
;
306 error
= btrfs_scan_one_device(match_strdup(&args
[0]),
307 flags
, holder
, fs_devices
);
320 * If no subvolume name is specified we use the default one. Allocate
321 * a copy of the string "." here so that code later in the
322 * mount path doesn't care if it's the default volume or another one.
325 *subvol_name
= kstrdup(".", GFP_KERNEL
);
332 static struct dentry
*get_default_root(struct super_block
*sb
,
335 struct btrfs_root
*root
= sb
->s_fs_info
;
336 struct btrfs_root
*new_root
;
337 struct btrfs_dir_item
*di
;
338 struct btrfs_path
*path
;
339 struct btrfs_key location
;
341 struct dentry
*dentry
;
346 * We have a specific subvol we want to mount, just setup location and
347 * go look up the root.
349 if (subvol_objectid
) {
350 location
.objectid
= subvol_objectid
;
351 location
.type
= BTRFS_ROOT_ITEM_KEY
;
352 location
.offset
= (u64
)-1;
356 path
= btrfs_alloc_path();
358 return ERR_PTR(-ENOMEM
);
359 path
->leave_spinning
= 1;
362 * Find the "default" dir item which points to the root item that we
363 * will mount by default if we haven't been given a specific subvolume
366 dir_id
= btrfs_super_root_dir(&root
->fs_info
->super_copy
);
367 di
= btrfs_lookup_dir_item(NULL
, root
, path
, dir_id
, "default", 7, 0);
372 * Ok the default dir item isn't there. This is weird since
373 * it's always been there, but don't freak out, just try and
374 * mount to root most subvolume.
376 btrfs_free_path(path
);
377 dir_id
= BTRFS_FIRST_FREE_OBJECTID
;
378 new_root
= root
->fs_info
->fs_root
;
382 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
383 btrfs_free_path(path
);
386 new_root
= btrfs_read_fs_root_no_name(root
->fs_info
, &location
);
387 if (IS_ERR(new_root
))
388 return ERR_PTR(PTR_ERR(new_root
));
390 if (btrfs_root_refs(&new_root
->root_item
) == 0)
391 return ERR_PTR(-ENOENT
);
393 dir_id
= btrfs_root_dirid(&new_root
->root_item
);
395 location
.objectid
= dir_id
;
396 location
.type
= BTRFS_INODE_ITEM_KEY
;
399 inode
= btrfs_iget(sb
, &location
, new_root
, &new);
401 return ERR_CAST(inode
);
404 * If we're just mounting the root most subvol put the inode and return
405 * a reference to the dentry. We will have already gotten a reference
406 * to the inode in btrfs_fill_super so we're good to go.
408 if (!new && sb
->s_root
->d_inode
== inode
) {
410 return dget(sb
->s_root
);
414 const struct qstr name
= { .name
= "/", .len
= 1 };
417 * New inode, we need to make the dentry a sibling of s_root so
418 * everything gets cleaned up properly on unmount.
420 dentry
= d_alloc(sb
->s_root
, &name
);
423 return ERR_PTR(-ENOMEM
);
425 d_splice_alias(inode
, dentry
);
428 * We found the inode in cache, just find a dentry for it and
429 * put the reference to the inode we just got.
431 dentry
= d_find_alias(inode
);
438 static int btrfs_fill_super(struct super_block
*sb
,
439 struct btrfs_fs_devices
*fs_devices
,
440 void *data
, int silent
)
443 struct dentry
*root_dentry
;
444 struct btrfs_super_block
*disk_super
;
445 struct btrfs_root
*tree_root
;
446 struct btrfs_key key
;
449 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
450 sb
->s_magic
= BTRFS_SUPER_MAGIC
;
451 sb
->s_op
= &btrfs_super_ops
;
452 sb
->s_export_op
= &btrfs_export_ops
;
453 sb
->s_xattr
= btrfs_xattr_handlers
;
455 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
456 sb
->s_flags
|= MS_POSIXACL
;
459 tree_root
= open_ctree(sb
, fs_devices
, (char *)data
);
461 if (IS_ERR(tree_root
)) {
462 printk("btrfs: open_ctree failed\n");
463 return PTR_ERR(tree_root
);
465 sb
->s_fs_info
= tree_root
;
466 disk_super
= &tree_root
->fs_info
->super_copy
;
468 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
469 key
.type
= BTRFS_INODE_ITEM_KEY
;
471 inode
= btrfs_iget(sb
, &key
, tree_root
->fs_info
->fs_root
, NULL
);
473 err
= PTR_ERR(inode
);
477 root_dentry
= d_alloc_root(inode
);
484 sb
->s_root
= root_dentry
;
486 save_mount_options(sb
, data
);
490 close_ctree(tree_root
);
494 int btrfs_sync_fs(struct super_block
*sb
, int wait
)
496 struct btrfs_trans_handle
*trans
;
497 struct btrfs_root
*root
= btrfs_sb(sb
);
501 filemap_flush(root
->fs_info
->btree_inode
->i_mapping
);
505 btrfs_start_delalloc_inodes(root
, 0);
506 btrfs_wait_ordered_extents(root
, 0, 0);
508 trans
= btrfs_start_transaction(root
, 0);
509 ret
= btrfs_commit_transaction(trans
, root
);
513 static int btrfs_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
515 struct btrfs_root
*root
= btrfs_sb(vfs
->mnt_sb
);
516 struct btrfs_fs_info
*info
= root
->fs_info
;
518 if (btrfs_test_opt(root
, DEGRADED
))
519 seq_puts(seq
, ",degraded");
520 if (btrfs_test_opt(root
, NODATASUM
))
521 seq_puts(seq
, ",nodatasum");
522 if (btrfs_test_opt(root
, NODATACOW
))
523 seq_puts(seq
, ",nodatacow");
524 if (btrfs_test_opt(root
, NOBARRIER
))
525 seq_puts(seq
, ",nobarrier");
526 if (info
->max_inline
!= 8192 * 1024)
527 seq_printf(seq
, ",max_inline=%llu",
528 (unsigned long long)info
->max_inline
);
529 if (info
->alloc_start
!= 0)
530 seq_printf(seq
, ",alloc_start=%llu",
531 (unsigned long long)info
->alloc_start
);
532 if (info
->thread_pool_size
!= min_t(unsigned long,
533 num_online_cpus() + 2, 8))
534 seq_printf(seq
, ",thread_pool=%d", info
->thread_pool_size
);
535 if (btrfs_test_opt(root
, COMPRESS
))
536 seq_puts(seq
, ",compress");
537 if (btrfs_test_opt(root
, NOSSD
))
538 seq_puts(seq
, ",nossd");
539 if (btrfs_test_opt(root
, SSD_SPREAD
))
540 seq_puts(seq
, ",ssd_spread");
541 else if (btrfs_test_opt(root
, SSD
))
542 seq_puts(seq
, ",ssd");
543 if (btrfs_test_opt(root
, NOTREELOG
))
544 seq_puts(seq
, ",notreelog");
545 if (btrfs_test_opt(root
, FLUSHONCOMMIT
))
546 seq_puts(seq
, ",flushoncommit");
547 if (btrfs_test_opt(root
, DISCARD
))
548 seq_puts(seq
, ",discard");
549 if (!(root
->fs_info
->sb
->s_flags
& MS_POSIXACL
))
550 seq_puts(seq
, ",noacl");
554 static int btrfs_test_super(struct super_block
*s
, void *data
)
556 struct btrfs_fs_devices
*test_fs_devices
= data
;
557 struct btrfs_root
*root
= btrfs_sb(s
);
559 return root
->fs_info
->fs_devices
== test_fs_devices
;
563 * Find a superblock for the given device / mount point.
565 * Note: This is based on get_sb_bdev from fs/super.c with a few additions
566 * for multiple device setup. Make sure to keep it in sync.
568 static int btrfs_get_sb(struct file_system_type
*fs_type
, int flags
,
569 const char *dev_name
, void *data
, struct vfsmount
*mnt
)
571 struct block_device
*bdev
= NULL
;
572 struct super_block
*s
;
574 struct btrfs_fs_devices
*fs_devices
= NULL
;
575 fmode_t mode
= FMODE_READ
;
576 char *subvol_name
= NULL
;
577 u64 subvol_objectid
= 0;
581 if (!(flags
& MS_RDONLY
))
584 error
= btrfs_parse_early_options(data
, mode
, fs_type
,
585 &subvol_name
, &subvol_objectid
,
590 error
= btrfs_scan_one_device(dev_name
, mode
, fs_type
, &fs_devices
);
592 goto error_free_subvol_name
;
594 error
= btrfs_open_devices(fs_devices
, mode
, fs_type
);
596 goto error_free_subvol_name
;
598 if (!(flags
& MS_RDONLY
) && fs_devices
->rw_devices
== 0) {
600 goto error_close_devices
;
603 bdev
= fs_devices
->latest_bdev
;
604 s
= sget(fs_type
, btrfs_test_super
, set_anon_super
, fs_devices
);
609 if ((flags
^ s
->s_flags
) & MS_RDONLY
) {
610 deactivate_locked_super(s
);
612 goto error_close_devices
;
616 btrfs_close_devices(fs_devices
);
618 char b
[BDEVNAME_SIZE
];
621 strlcpy(s
->s_id
, bdevname(bdev
, b
), sizeof(s
->s_id
));
622 error
= btrfs_fill_super(s
, fs_devices
, data
,
623 flags
& MS_SILENT
? 1 : 0);
625 deactivate_locked_super(s
);
626 goto error_free_subvol_name
;
629 btrfs_sb(s
)->fs_info
->bdev_holder
= fs_type
;
630 s
->s_flags
|= MS_ACTIVE
;
633 root
= get_default_root(s
, subvol_objectid
);
635 error
= PTR_ERR(root
);
636 deactivate_locked_super(s
);
639 /* if they gave us a subvolume name bind mount into that */
640 if (strcmp(subvol_name
, ".")) {
641 struct dentry
*new_root
;
642 mutex_lock(&root
->d_inode
->i_mutex
);
643 new_root
= lookup_one_len(subvol_name
, root
,
644 strlen(subvol_name
));
645 mutex_unlock(&root
->d_inode
->i_mutex
);
647 if (IS_ERR(new_root
)) {
648 deactivate_locked_super(s
);
649 error
= PTR_ERR(new_root
);
651 goto error_close_devices
;
653 if (!new_root
->d_inode
) {
656 deactivate_locked_super(s
);
658 goto error_close_devices
;
665 mnt
->mnt_root
= root
;
673 btrfs_close_devices(fs_devices
);
674 error_free_subvol_name
:
680 static int btrfs_remount(struct super_block
*sb
, int *flags
, char *data
)
682 struct btrfs_root
*root
= btrfs_sb(sb
);
685 ret
= btrfs_parse_options(root
, data
);
689 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
692 if (*flags
& MS_RDONLY
) {
693 sb
->s_flags
|= MS_RDONLY
;
695 ret
= btrfs_commit_super(root
);
698 if (root
->fs_info
->fs_devices
->rw_devices
== 0)
701 if (btrfs_super_log_root(&root
->fs_info
->super_copy
) != 0)
704 ret
= btrfs_cleanup_fs_roots(root
->fs_info
);
707 /* recover relocation */
708 ret
= btrfs_recover_relocation(root
);
711 sb
->s_flags
&= ~MS_RDONLY
;
717 static int btrfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
719 struct btrfs_root
*root
= btrfs_sb(dentry
->d_sb
);
720 struct btrfs_super_block
*disk_super
= &root
->fs_info
->super_copy
;
721 struct list_head
*head
= &root
->fs_info
->space_info
;
722 struct btrfs_space_info
*found
;
724 int bits
= dentry
->d_sb
->s_blocksize_bits
;
725 __be32
*fsid
= (__be32
*)root
->fs_info
->fsid
;
728 list_for_each_entry_rcu(found
, head
, list
)
729 total_used
+= found
->disk_used
;
732 buf
->f_namelen
= BTRFS_NAME_LEN
;
733 buf
->f_blocks
= btrfs_super_total_bytes(disk_super
) >> bits
;
734 buf
->f_bfree
= buf
->f_blocks
- (total_used
>> bits
);
735 buf
->f_bavail
= buf
->f_bfree
;
736 buf
->f_bsize
= dentry
->d_sb
->s_blocksize
;
737 buf
->f_type
= BTRFS_SUPER_MAGIC
;
739 /* We treat it as constant endianness (it doesn't matter _which_)
740 because we want the fsid to come out the same whether mounted
741 on a big-endian or little-endian host */
742 buf
->f_fsid
.val
[0] = be32_to_cpu(fsid
[0]) ^ be32_to_cpu(fsid
[2]);
743 buf
->f_fsid
.val
[1] = be32_to_cpu(fsid
[1]) ^ be32_to_cpu(fsid
[3]);
744 /* Mask in the root object ID too, to disambiguate subvols */
745 buf
->f_fsid
.val
[0] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
>> 32;
746 buf
->f_fsid
.val
[1] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
;
751 static struct file_system_type btrfs_fs_type
= {
752 .owner
= THIS_MODULE
,
754 .get_sb
= btrfs_get_sb
,
755 .kill_sb
= kill_anon_super
,
756 .fs_flags
= FS_REQUIRES_DEV
,
760 * used by btrfsctl to scan devices when no FS is mounted
762 static long btrfs_control_ioctl(struct file
*file
, unsigned int cmd
,
765 struct btrfs_ioctl_vol_args
*vol
;
766 struct btrfs_fs_devices
*fs_devices
;
769 if (!capable(CAP_SYS_ADMIN
))
772 vol
= memdup_user((void __user
*)arg
, sizeof(*vol
));
777 case BTRFS_IOC_SCAN_DEV
:
778 ret
= btrfs_scan_one_device(vol
->name
, FMODE_READ
,
779 &btrfs_fs_type
, &fs_devices
);
787 static int btrfs_freeze(struct super_block
*sb
)
789 struct btrfs_root
*root
= btrfs_sb(sb
);
790 mutex_lock(&root
->fs_info
->transaction_kthread_mutex
);
791 mutex_lock(&root
->fs_info
->cleaner_mutex
);
795 static int btrfs_unfreeze(struct super_block
*sb
)
797 struct btrfs_root
*root
= btrfs_sb(sb
);
798 mutex_unlock(&root
->fs_info
->cleaner_mutex
);
799 mutex_unlock(&root
->fs_info
->transaction_kthread_mutex
);
803 static const struct super_operations btrfs_super_ops
= {
804 .drop_inode
= btrfs_drop_inode
,
805 .evict_inode
= btrfs_evict_inode
,
806 .put_super
= btrfs_put_super
,
807 .sync_fs
= btrfs_sync_fs
,
808 .show_options
= btrfs_show_options
,
809 .write_inode
= btrfs_write_inode
,
810 .dirty_inode
= btrfs_dirty_inode
,
811 .alloc_inode
= btrfs_alloc_inode
,
812 .destroy_inode
= btrfs_destroy_inode
,
813 .statfs
= btrfs_statfs
,
814 .remount_fs
= btrfs_remount
,
815 .freeze_fs
= btrfs_freeze
,
816 .unfreeze_fs
= btrfs_unfreeze
,
819 static const struct file_operations btrfs_ctl_fops
= {
820 .unlocked_ioctl
= btrfs_control_ioctl
,
821 .compat_ioctl
= btrfs_control_ioctl
,
822 .owner
= THIS_MODULE
,
825 static struct miscdevice btrfs_misc
= {
826 .minor
= BTRFS_MINOR
,
827 .name
= "btrfs-control",
828 .fops
= &btrfs_ctl_fops
831 MODULE_ALIAS_MISCDEV(BTRFS_MINOR
);
832 MODULE_ALIAS("devname:btrfs-control");
834 static int btrfs_interface_init(void)
836 return misc_register(&btrfs_misc
);
839 static void btrfs_interface_exit(void)
841 if (misc_deregister(&btrfs_misc
) < 0)
842 printk(KERN_INFO
"misc_deregister failed for control device");
845 static int __init
init_btrfs_fs(void)
849 err
= btrfs_init_sysfs();
853 err
= btrfs_init_cachep();
857 err
= extent_io_init();
861 err
= extent_map_init();
865 err
= btrfs_interface_init();
867 goto free_extent_map
;
869 err
= register_filesystem(&btrfs_fs_type
);
871 goto unregister_ioctl
;
873 printk(KERN_INFO
"%s loaded\n", BTRFS_BUILD_VERSION
);
877 btrfs_interface_exit();
883 btrfs_destroy_cachep();
889 static void __exit
exit_btrfs_fs(void)
891 btrfs_destroy_cachep();
894 btrfs_interface_exit();
895 unregister_filesystem(&btrfs_fs_type
);
897 btrfs_cleanup_fs_uuids();
901 module_init(init_btrfs_fs
)
902 module_exit(exit_btrfs_fs
)
904 MODULE_LICENSE("GPL");