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>
44 #include "transaction.h"
45 #include "btrfs_inode.h"
47 #include "print-tree.h"
52 #include "compression.h"
54 static const struct super_operations btrfs_super_ops
;
56 static void btrfs_put_super(struct super_block
*sb
)
58 struct btrfs_root
*root
= btrfs_sb(sb
);
61 ret
= close_ctree(root
);
66 Opt_degraded
, Opt_subvol
, Opt_subvolid
, Opt_device
, Opt_nodatasum
,
67 Opt_nodatacow
, Opt_max_extent
, Opt_max_inline
, Opt_alloc_start
,
68 Opt_nobarrier
, Opt_ssd
, Opt_nossd
, Opt_ssd_spread
, Opt_thread_pool
,
69 Opt_noacl
, Opt_compress
, Opt_compress_force
, Opt_notreelog
, Opt_ratio
,
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_extent
, "max_extent=%s"},
83 {Opt_max_inline
, "max_inline=%s"},
84 {Opt_alloc_start
, "alloc_start=%s"},
85 {Opt_thread_pool
, "thread_pool=%d"},
86 {Opt_compress
, "compress"},
87 {Opt_compress_force
, "compress-force"},
89 {Opt_ssd_spread
, "ssd_spread"},
92 {Opt_notreelog
, "notreelog"},
93 {Opt_flushoncommit
, "flushoncommit"},
94 {Opt_ratio
, "metadata_ratio=%d"},
95 {Opt_discard
, "discard"},
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_extent
= memparse(num
, NULL
);
197 info
->max_extent
= max_t(u64
,
198 info
->max_extent
, root
->sectorsize
);
199 printk(KERN_INFO
"btrfs: max_extent at %llu\n",
200 (unsigned long long)info
->max_extent
);
204 num
= match_strdup(&args
[0]);
206 info
->max_inline
= memparse(num
, NULL
);
209 if (info
->max_inline
) {
210 info
->max_inline
= max_t(u64
,
214 printk(KERN_INFO
"btrfs: max_inline at %llu\n",
215 (unsigned long long)info
->max_inline
);
218 case Opt_alloc_start
:
219 num
= match_strdup(&args
[0]);
221 info
->alloc_start
= memparse(num
, NULL
);
224 "btrfs: allocations start at %llu\n",
225 (unsigned long long)info
->alloc_start
);
229 root
->fs_info
->sb
->s_flags
&= ~MS_POSIXACL
;
232 printk(KERN_INFO
"btrfs: disabling tree log\n");
233 btrfs_set_opt(info
->mount_opt
, NOTREELOG
);
235 case Opt_flushoncommit
:
236 printk(KERN_INFO
"btrfs: turning on flush-on-commit\n");
237 btrfs_set_opt(info
->mount_opt
, FLUSHONCOMMIT
);
241 match_int(&args
[0], &intarg
);
243 info
->metadata_ratio
= intarg
;
244 printk(KERN_INFO
"btrfs: metadata ratio %d\n",
245 info
->metadata_ratio
);
249 btrfs_set_opt(info
->mount_opt
, DISCARD
);
252 printk(KERN_INFO
"btrfs: unrecognized mount option "
266 * Parse mount options that are required early in the mount process.
268 * All other options will be parsed on much later in the mount process and
269 * only when we need to allocate a new super block.
271 static int btrfs_parse_early_options(const char *options
, fmode_t flags
,
272 void *holder
, char **subvol_name
, u64
*subvol_objectid
,
273 struct btrfs_fs_devices
**fs_devices
)
275 substring_t args
[MAX_OPT_ARGS
];
284 * strsep changes the string, duplicate it because parse_options
287 opts
= kstrdup(options
, GFP_KERNEL
);
291 while ((p
= strsep(&opts
, ",")) != NULL
) {
296 token
= match_token(p
, tokens
, args
);
299 *subvol_name
= match_strdup(&args
[0]);
303 error
= match_int(&args
[0], &intarg
);
305 /* we want the original fs_tree */
308 BTRFS_FS_TREE_OBJECTID
;
310 *subvol_objectid
= intarg
;
314 error
= btrfs_scan_one_device(match_strdup(&args
[0]),
315 flags
, holder
, fs_devices
);
328 * If no subvolume name is specified we use the default one. Allocate
329 * a copy of the string "." here so that code later in the
330 * mount path doesn't care if it's the default volume or another one.
333 *subvol_name
= kstrdup(".", GFP_KERNEL
);
340 static struct dentry
*get_default_root(struct super_block
*sb
,
343 struct btrfs_root
*root
= sb
->s_fs_info
;
344 struct btrfs_root
*new_root
;
345 struct btrfs_dir_item
*di
;
346 struct btrfs_path
*path
;
347 struct btrfs_key location
;
349 struct dentry
*dentry
;
354 * We have a specific subvol we want to mount, just setup location and
355 * go look up the root.
357 if (subvol_objectid
) {
358 location
.objectid
= subvol_objectid
;
359 location
.type
= BTRFS_ROOT_ITEM_KEY
;
360 location
.offset
= (u64
)-1;
364 path
= btrfs_alloc_path();
366 return ERR_PTR(-ENOMEM
);
367 path
->leave_spinning
= 1;
370 * Find the "default" dir item which points to the root item that we
371 * will mount by default if we haven't been given a specific subvolume
374 dir_id
= btrfs_super_root_dir(&root
->fs_info
->super_copy
);
375 di
= btrfs_lookup_dir_item(NULL
, root
, path
, dir_id
, "default", 7, 0);
378 * Ok the default dir item isn't there. This is weird since
379 * it's always been there, but don't freak out, just try and
380 * mount to root most subvolume.
382 btrfs_free_path(path
);
383 dir_id
= BTRFS_FIRST_FREE_OBJECTID
;
384 new_root
= root
->fs_info
->fs_root
;
388 btrfs_dir_item_key_to_cpu(path
->nodes
[0], di
, &location
);
389 btrfs_free_path(path
);
392 new_root
= btrfs_read_fs_root_no_name(root
->fs_info
, &location
);
393 if (IS_ERR(new_root
))
394 return ERR_PTR(PTR_ERR(new_root
));
396 if (btrfs_root_refs(&new_root
->root_item
) == 0)
397 return ERR_PTR(-ENOENT
);
399 dir_id
= btrfs_root_dirid(&new_root
->root_item
);
401 location
.objectid
= dir_id
;
402 location
.type
= BTRFS_INODE_ITEM_KEY
;
405 inode
= btrfs_iget(sb
, &location
, new_root
, &new);
407 return ERR_PTR(-ENOMEM
);
410 * If we're just mounting the root most subvol put the inode and return
411 * a reference to the dentry. We will have already gotten a reference
412 * to the inode in btrfs_fill_super so we're good to go.
414 if (!new && sb
->s_root
->d_inode
== inode
) {
416 return dget(sb
->s_root
);
420 const struct qstr name
= { .name
= "/", .len
= 1 };
423 * New inode, we need to make the dentry a sibling of s_root so
424 * everything gets cleaned up properly on unmount.
426 dentry
= d_alloc(sb
->s_root
, &name
);
429 return ERR_PTR(-ENOMEM
);
431 d_splice_alias(inode
, dentry
);
434 * We found the inode in cache, just find a dentry for it and
435 * put the reference to the inode we just got.
437 dentry
= d_find_alias(inode
);
444 static int btrfs_fill_super(struct super_block
*sb
,
445 struct btrfs_fs_devices
*fs_devices
,
446 void *data
, int silent
)
449 struct dentry
*root_dentry
;
450 struct btrfs_super_block
*disk_super
;
451 struct btrfs_root
*tree_root
;
452 struct btrfs_key key
;
455 sb
->s_maxbytes
= MAX_LFS_FILESIZE
;
456 sb
->s_magic
= BTRFS_SUPER_MAGIC
;
457 sb
->s_op
= &btrfs_super_ops
;
458 sb
->s_export_op
= &btrfs_export_ops
;
459 sb
->s_xattr
= btrfs_xattr_handlers
;
461 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
462 sb
->s_flags
|= MS_POSIXACL
;
465 tree_root
= open_ctree(sb
, fs_devices
, (char *)data
);
467 if (IS_ERR(tree_root
)) {
468 printk("btrfs: open_ctree failed\n");
469 return PTR_ERR(tree_root
);
471 sb
->s_fs_info
= tree_root
;
472 disk_super
= &tree_root
->fs_info
->super_copy
;
474 key
.objectid
= BTRFS_FIRST_FREE_OBJECTID
;
475 key
.type
= BTRFS_INODE_ITEM_KEY
;
477 inode
= btrfs_iget(sb
, &key
, tree_root
->fs_info
->fs_root
, NULL
);
479 err
= PTR_ERR(inode
);
483 root_dentry
= d_alloc_root(inode
);
490 sb
->s_root
= root_dentry
;
492 save_mount_options(sb
, data
);
496 close_ctree(tree_root
);
500 int btrfs_sync_fs(struct super_block
*sb
, int wait
)
502 struct btrfs_trans_handle
*trans
;
503 struct btrfs_root
*root
= btrfs_sb(sb
);
507 filemap_flush(root
->fs_info
->btree_inode
->i_mapping
);
511 btrfs_start_delalloc_inodes(root
, 0);
512 btrfs_wait_ordered_extents(root
, 0, 0);
514 trans
= btrfs_start_transaction(root
, 1);
515 ret
= btrfs_commit_transaction(trans
, root
);
519 static int btrfs_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
521 struct btrfs_root
*root
= btrfs_sb(vfs
->mnt_sb
);
522 struct btrfs_fs_info
*info
= root
->fs_info
;
524 if (btrfs_test_opt(root
, DEGRADED
))
525 seq_puts(seq
, ",degraded");
526 if (btrfs_test_opt(root
, NODATASUM
))
527 seq_puts(seq
, ",nodatasum");
528 if (btrfs_test_opt(root
, NODATACOW
))
529 seq_puts(seq
, ",nodatacow");
530 if (btrfs_test_opt(root
, NOBARRIER
))
531 seq_puts(seq
, ",nobarrier");
532 if (info
->max_extent
!= (u64
)-1)
533 seq_printf(seq
, ",max_extent=%llu",
534 (unsigned long long)info
->max_extent
);
535 if (info
->max_inline
!= 8192 * 1024)
536 seq_printf(seq
, ",max_inline=%llu",
537 (unsigned long long)info
->max_inline
);
538 if (info
->alloc_start
!= 0)
539 seq_printf(seq
, ",alloc_start=%llu",
540 (unsigned long long)info
->alloc_start
);
541 if (info
->thread_pool_size
!= min_t(unsigned long,
542 num_online_cpus() + 2, 8))
543 seq_printf(seq
, ",thread_pool=%d", info
->thread_pool_size
);
544 if (btrfs_test_opt(root
, COMPRESS
))
545 seq_puts(seq
, ",compress");
546 if (btrfs_test_opt(root
, NOSSD
))
547 seq_puts(seq
, ",nossd");
548 if (btrfs_test_opt(root
, SSD_SPREAD
))
549 seq_puts(seq
, ",ssd_spread");
550 else if (btrfs_test_opt(root
, SSD
))
551 seq_puts(seq
, ",ssd");
552 if (btrfs_test_opt(root
, NOTREELOG
))
553 seq_puts(seq
, ",notreelog");
554 if (btrfs_test_opt(root
, FLUSHONCOMMIT
))
555 seq_puts(seq
, ",flushoncommit");
556 if (btrfs_test_opt(root
, DISCARD
))
557 seq_puts(seq
, ",discard");
558 if (!(root
->fs_info
->sb
->s_flags
& MS_POSIXACL
))
559 seq_puts(seq
, ",noacl");
563 static int btrfs_test_super(struct super_block
*s
, void *data
)
565 struct btrfs_fs_devices
*test_fs_devices
= data
;
566 struct btrfs_root
*root
= btrfs_sb(s
);
568 return root
->fs_info
->fs_devices
== test_fs_devices
;
572 * Find a superblock for the given device / mount point.
574 * Note: This is based on get_sb_bdev from fs/super.c with a few additions
575 * for multiple device setup. Make sure to keep it in sync.
577 static int btrfs_get_sb(struct file_system_type
*fs_type
, int flags
,
578 const char *dev_name
, void *data
, struct vfsmount
*mnt
)
580 struct block_device
*bdev
= NULL
;
581 struct super_block
*s
;
583 struct btrfs_fs_devices
*fs_devices
= NULL
;
584 fmode_t mode
= FMODE_READ
;
585 char *subvol_name
= NULL
;
586 u64 subvol_objectid
= 0;
590 if (!(flags
& MS_RDONLY
))
593 error
= btrfs_parse_early_options(data
, mode
, fs_type
,
594 &subvol_name
, &subvol_objectid
,
599 error
= btrfs_scan_one_device(dev_name
, mode
, fs_type
, &fs_devices
);
601 goto error_free_subvol_name
;
603 error
= btrfs_open_devices(fs_devices
, mode
, fs_type
);
605 goto error_free_subvol_name
;
607 if (!(flags
& MS_RDONLY
) && fs_devices
->rw_devices
== 0) {
609 goto error_close_devices
;
612 bdev
= fs_devices
->latest_bdev
;
613 s
= sget(fs_type
, btrfs_test_super
, set_anon_super
, fs_devices
);
618 if ((flags
^ s
->s_flags
) & MS_RDONLY
) {
619 deactivate_locked_super(s
);
621 goto error_close_devices
;
625 btrfs_close_devices(fs_devices
);
627 char b
[BDEVNAME_SIZE
];
630 strlcpy(s
->s_id
, bdevname(bdev
, b
), sizeof(s
->s_id
));
631 error
= btrfs_fill_super(s
, fs_devices
, data
,
632 flags
& MS_SILENT
? 1 : 0);
634 deactivate_locked_super(s
);
635 goto error_free_subvol_name
;
638 btrfs_sb(s
)->fs_info
->bdev_holder
= fs_type
;
639 s
->s_flags
|= MS_ACTIVE
;
642 root
= get_default_root(s
, subvol_objectid
);
644 error
= PTR_ERR(root
);
645 deactivate_locked_super(s
);
648 /* if they gave us a subvolume name bind mount into that */
649 if (strcmp(subvol_name
, ".")) {
650 struct dentry
*new_root
;
651 mutex_lock(&root
->d_inode
->i_mutex
);
652 new_root
= lookup_one_len(subvol_name
, root
,
653 strlen(subvol_name
));
654 mutex_unlock(&root
->d_inode
->i_mutex
);
656 if (IS_ERR(new_root
)) {
657 deactivate_locked_super(s
);
658 error
= PTR_ERR(new_root
);
660 goto error_close_devices
;
662 if (!new_root
->d_inode
) {
665 deactivate_locked_super(s
);
667 goto error_close_devices
;
674 mnt
->mnt_root
= root
;
682 btrfs_close_devices(fs_devices
);
683 error_free_subvol_name
:
689 static int btrfs_remount(struct super_block
*sb
, int *flags
, char *data
)
691 struct btrfs_root
*root
= btrfs_sb(sb
);
694 ret
= btrfs_parse_options(root
, data
);
698 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
))
701 if (*flags
& MS_RDONLY
) {
702 sb
->s_flags
|= MS_RDONLY
;
704 ret
= btrfs_commit_super(root
);
707 if (root
->fs_info
->fs_devices
->rw_devices
== 0)
710 if (btrfs_super_log_root(&root
->fs_info
->super_copy
) != 0)
713 /* recover relocation */
714 ret
= btrfs_recover_relocation(root
);
717 ret
= btrfs_cleanup_fs_roots(root
->fs_info
);
720 sb
->s_flags
&= ~MS_RDONLY
;
726 static int btrfs_statfs(struct dentry
*dentry
, struct kstatfs
*buf
)
728 struct btrfs_root
*root
= btrfs_sb(dentry
->d_sb
);
729 struct btrfs_super_block
*disk_super
= &root
->fs_info
->super_copy
;
730 struct list_head
*head
= &root
->fs_info
->space_info
;
731 struct btrfs_space_info
*found
;
734 int bits
= dentry
->d_sb
->s_blocksize_bits
;
735 __be32
*fsid
= (__be32
*)root
->fs_info
->fsid
;
738 list_for_each_entry_rcu(found
, head
, list
) {
739 if (found
->flags
& (BTRFS_BLOCK_GROUP_DUP
|
740 BTRFS_BLOCK_GROUP_RAID10
|
741 BTRFS_BLOCK_GROUP_RAID1
)) {
742 total_used
+= found
->bytes_used
;
743 if (found
->flags
& BTRFS_BLOCK_GROUP_DATA
)
744 data_used
+= found
->bytes_used
;
746 data_used
+= found
->total_bytes
;
749 total_used
+= found
->bytes_used
;
750 if (found
->flags
& BTRFS_BLOCK_GROUP_DATA
)
751 data_used
+= found
->bytes_used
;
753 data_used
+= found
->total_bytes
;
757 buf
->f_namelen
= BTRFS_NAME_LEN
;
758 buf
->f_blocks
= btrfs_super_total_bytes(disk_super
) >> bits
;
759 buf
->f_bfree
= buf
->f_blocks
- (total_used
>> bits
);
760 buf
->f_bavail
= buf
->f_blocks
- (data_used
>> bits
);
761 buf
->f_bsize
= dentry
->d_sb
->s_blocksize
;
762 buf
->f_type
= BTRFS_SUPER_MAGIC
;
764 /* We treat it as constant endianness (it doesn't matter _which_)
765 because we want the fsid to come out the same whether mounted
766 on a big-endian or little-endian host */
767 buf
->f_fsid
.val
[0] = be32_to_cpu(fsid
[0]) ^ be32_to_cpu(fsid
[2]);
768 buf
->f_fsid
.val
[1] = be32_to_cpu(fsid
[1]) ^ be32_to_cpu(fsid
[3]);
769 /* Mask in the root object ID too, to disambiguate subvols */
770 buf
->f_fsid
.val
[0] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
>> 32;
771 buf
->f_fsid
.val
[1] ^= BTRFS_I(dentry
->d_inode
)->root
->objectid
;
776 static struct file_system_type btrfs_fs_type
= {
777 .owner
= THIS_MODULE
,
779 .get_sb
= btrfs_get_sb
,
780 .kill_sb
= kill_anon_super
,
781 .fs_flags
= FS_REQUIRES_DEV
,
785 * used by btrfsctl to scan devices when no FS is mounted
787 static long btrfs_control_ioctl(struct file
*file
, unsigned int cmd
,
790 struct btrfs_ioctl_vol_args
*vol
;
791 struct btrfs_fs_devices
*fs_devices
;
794 if (!capable(CAP_SYS_ADMIN
))
797 vol
= memdup_user((void __user
*)arg
, sizeof(*vol
));
802 case BTRFS_IOC_SCAN_DEV
:
803 ret
= btrfs_scan_one_device(vol
->name
, FMODE_READ
,
804 &btrfs_fs_type
, &fs_devices
);
812 static int btrfs_freeze(struct super_block
*sb
)
814 struct btrfs_root
*root
= btrfs_sb(sb
);
815 mutex_lock(&root
->fs_info
->transaction_kthread_mutex
);
816 mutex_lock(&root
->fs_info
->cleaner_mutex
);
820 static int btrfs_unfreeze(struct super_block
*sb
)
822 struct btrfs_root
*root
= btrfs_sb(sb
);
823 mutex_unlock(&root
->fs_info
->cleaner_mutex
);
824 mutex_unlock(&root
->fs_info
->transaction_kthread_mutex
);
828 static const struct super_operations btrfs_super_ops
= {
829 .drop_inode
= btrfs_drop_inode
,
830 .delete_inode
= btrfs_delete_inode
,
831 .put_super
= btrfs_put_super
,
832 .sync_fs
= btrfs_sync_fs
,
833 .show_options
= btrfs_show_options
,
834 .write_inode
= btrfs_write_inode
,
835 .dirty_inode
= btrfs_dirty_inode
,
836 .alloc_inode
= btrfs_alloc_inode
,
837 .destroy_inode
= btrfs_destroy_inode
,
838 .statfs
= btrfs_statfs
,
839 .remount_fs
= btrfs_remount
,
840 .freeze_fs
= btrfs_freeze
,
841 .unfreeze_fs
= btrfs_unfreeze
,
844 static const struct file_operations btrfs_ctl_fops
= {
845 .unlocked_ioctl
= btrfs_control_ioctl
,
846 .compat_ioctl
= btrfs_control_ioctl
,
847 .owner
= THIS_MODULE
,
850 static struct miscdevice btrfs_misc
= {
851 .minor
= MISC_DYNAMIC_MINOR
,
852 .name
= "btrfs-control",
853 .fops
= &btrfs_ctl_fops
856 static int btrfs_interface_init(void)
858 return misc_register(&btrfs_misc
);
861 static void btrfs_interface_exit(void)
863 if (misc_deregister(&btrfs_misc
) < 0)
864 printk(KERN_INFO
"misc_deregister failed for control device");
867 static int __init
init_btrfs_fs(void)
871 err
= btrfs_init_sysfs();
875 err
= btrfs_init_cachep();
879 err
= extent_io_init();
883 err
= extent_map_init();
887 err
= btrfs_interface_init();
889 goto free_extent_map
;
891 err
= register_filesystem(&btrfs_fs_type
);
893 goto unregister_ioctl
;
895 printk(KERN_INFO
"%s loaded\n", BTRFS_BUILD_VERSION
);
899 btrfs_interface_exit();
905 btrfs_destroy_cachep();
911 static void __exit
exit_btrfs_fs(void)
913 btrfs_destroy_cachep();
916 btrfs_interface_exit();
917 unregister_filesystem(&btrfs_fs_type
);
919 btrfs_cleanup_fs_uuids();
923 module_init(init_btrfs_fs
)
924 module_exit(exit_btrfs_fs
)
926 MODULE_LICENSE("GPL");