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6cbd5570 CM |
1 | /* |
2 | * Copyright (C) 2007 Oracle. All rights reserved. | |
3 | * | |
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. | |
7 | * | |
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. | |
12 | * | |
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. | |
17 | */ | |
18 | ||
4b82d6e4 | 19 | #include <linux/blkdev.h> |
2e635a27 | 20 | #include <linux/module.h> |
e20d96d6 | 21 | #include <linux/buffer_head.h> |
2e635a27 CM |
22 | #include <linux/fs.h> |
23 | #include <linux/pagemap.h> | |
24 | #include <linux/highmem.h> | |
25 | #include <linux/time.h> | |
26 | #include <linux/init.h> | |
a9572a15 | 27 | #include <linux/seq_file.h> |
2e635a27 | 28 | #include <linux/string.h> |
2e635a27 | 29 | #include <linux/backing-dev.h> |
4b82d6e4 | 30 | #include <linux/mount.h> |
dee26a9f | 31 | #include <linux/mpage.h> |
75dfe396 CM |
32 | #include <linux/swap.h> |
33 | #include <linux/writeback.h> | |
8fd17795 | 34 | #include <linux/statfs.h> |
08607c1b | 35 | #include <linux/compat.h> |
95e05289 | 36 | #include <linux/parser.h> |
c59f8951 | 37 | #include <linux/ctype.h> |
6da6abae | 38 | #include <linux/namei.h> |
a9218f6b | 39 | #include <linux/miscdevice.h> |
1bcbf313 | 40 | #include <linux/magic.h> |
5a0e3ad6 | 41 | #include <linux/slab.h> |
4b4e25f2 | 42 | #include "compat.h" |
2e635a27 | 43 | #include "ctree.h" |
e20d96d6 | 44 | #include "disk-io.h" |
d5719762 | 45 | #include "transaction.h" |
2c90e5d6 | 46 | #include "btrfs_inode.h" |
c5739bba | 47 | #include "ioctl.h" |
3a686375 | 48 | #include "print-tree.h" |
5103e947 | 49 | #include "xattr.h" |
8a4b83cc | 50 | #include "volumes.h" |
b3c3da71 | 51 | #include "version.h" |
be6e8dc0 | 52 | #include "export.h" |
c8b97818 | 53 | #include "compression.h" |
2e635a27 | 54 | |
b87221de | 55 | static const struct super_operations btrfs_super_ops; |
75dfe396 | 56 | |
d397712b | 57 | static void btrfs_put_super(struct super_block *sb) |
b18c6685 | 58 | { |
39279cc3 | 59 | struct btrfs_root *root = btrfs_sb(sb); |
b18c6685 | 60 | int ret; |
b18c6685 | 61 | |
39279cc3 | 62 | ret = close_ctree(root); |
39279cc3 | 63 | sb->s_fs_info = NULL; |
559af821 AK |
64 | |
65 | (void)ret; /* FIXME: need to fix VFS to return error? */ | |
75dfe396 CM |
66 | } |
67 | ||
95e05289 | 68 | enum { |
73f73415 | 69 | Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, |
287a0ab9 JB |
70 | Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, |
71 | Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, | |
261507a0 LZ |
72 | Opt_compress_type, Opt_compress_force, Opt_compress_force_type, |
73 | Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, | |
74 | Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, Opt_err, | |
95e05289 CM |
75 | }; |
76 | ||
77 | static match_table_t tokens = { | |
dfe25020 | 78 | {Opt_degraded, "degraded"}, |
95e05289 | 79 | {Opt_subvol, "subvol=%s"}, |
73f73415 | 80 | {Opt_subvolid, "subvolid=%d"}, |
43e570b0 | 81 | {Opt_device, "device=%s"}, |
b6cda9bc | 82 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 83 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 84 | {Opt_nobarrier, "nobarrier"}, |
6f568d35 | 85 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 86 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 87 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 88 | {Opt_compress, "compress"}, |
261507a0 | 89 | {Opt_compress_type, "compress=%s"}, |
a555f810 | 90 | {Opt_compress_force, "compress-force"}, |
261507a0 | 91 | {Opt_compress_force_type, "compress-force=%s"}, |
e18e4809 | 92 | {Opt_ssd, "ssd"}, |
451d7585 | 93 | {Opt_ssd_spread, "ssd_spread"}, |
3b30c22f | 94 | {Opt_nossd, "nossd"}, |
33268eaf | 95 | {Opt_noacl, "noacl"}, |
3a5e1404 | 96 | {Opt_notreelog, "notreelog"}, |
dccae999 | 97 | {Opt_flushoncommit, "flushoncommit"}, |
97e728d4 | 98 | {Opt_ratio, "metadata_ratio=%d"}, |
e244a0ae | 99 | {Opt_discard, "discard"}, |
0af3d00b | 100 | {Opt_space_cache, "space_cache"}, |
88c2ba3b | 101 | {Opt_clear_cache, "clear_cache"}, |
4260f7c7 | 102 | {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, |
33268eaf | 103 | {Opt_err, NULL}, |
95e05289 CM |
104 | }; |
105 | ||
edf24abe CH |
106 | /* |
107 | * Regular mount options parser. Everything that is needed only when | |
108 | * reading in a new superblock is parsed here. | |
109 | */ | |
110 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 111 | { |
edf24abe | 112 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 113 | substring_t args[MAX_OPT_ARGS]; |
da495ecc | 114 | char *p, *num, *orig; |
4543df7e | 115 | int intarg; |
a7a3f7ca | 116 | int ret = 0; |
261507a0 LZ |
117 | char *compress_type; |
118 | bool compress_force = false; | |
b6cda9bc | 119 | |
95e05289 | 120 | if (!options) |
edf24abe | 121 | return 0; |
95e05289 | 122 | |
be20aa9d CM |
123 | /* |
124 | * strsep changes the string, duplicate it because parse_options | |
125 | * gets called twice | |
126 | */ | |
127 | options = kstrdup(options, GFP_NOFS); | |
128 | if (!options) | |
129 | return -ENOMEM; | |
130 | ||
da495ecc | 131 | orig = options; |
be20aa9d | 132 | |
edf24abe | 133 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
134 | int token; |
135 | if (!*p) | |
136 | continue; | |
137 | ||
138 | token = match_token(p, tokens, args); | |
139 | switch (token) { | |
dfe25020 | 140 | case Opt_degraded: |
edf24abe CH |
141 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
142 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 143 | break; |
95e05289 | 144 | case Opt_subvol: |
73f73415 | 145 | case Opt_subvolid: |
43e570b0 | 146 | case Opt_device: |
edf24abe | 147 | /* |
43e570b0 | 148 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
149 | * and can be happily ignored here. |
150 | */ | |
b6cda9bc CM |
151 | break; |
152 | case Opt_nodatasum: | |
067c28ad | 153 | printk(KERN_INFO "btrfs: setting nodatasum\n"); |
edf24abe | 154 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
155 | break; |
156 | case Opt_nodatacow: | |
edf24abe CH |
157 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
158 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
159 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 160 | break; |
a555f810 | 161 | case Opt_compress_force: |
261507a0 LZ |
162 | case Opt_compress_force_type: |
163 | compress_force = true; | |
164 | case Opt_compress: | |
165 | case Opt_compress_type: | |
166 | if (token == Opt_compress || | |
167 | token == Opt_compress_force || | |
168 | strcmp(args[0].from, "zlib") == 0) { | |
169 | compress_type = "zlib"; | |
170 | info->compress_type = BTRFS_COMPRESS_ZLIB; | |
171 | } else { | |
172 | ret = -EINVAL; | |
173 | goto out; | |
174 | } | |
175 | ||
a555f810 | 176 | btrfs_set_opt(info->mount_opt, COMPRESS); |
261507a0 LZ |
177 | if (compress_force) { |
178 | btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); | |
179 | pr_info("btrfs: force %s compression\n", | |
180 | compress_type); | |
181 | } else | |
182 | pr_info("btrfs: use %s compression\n", | |
183 | compress_type); | |
a555f810 | 184 | break; |
e18e4809 | 185 | case Opt_ssd: |
edf24abe CH |
186 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
187 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 188 | break; |
451d7585 CM |
189 | case Opt_ssd_spread: |
190 | printk(KERN_INFO "btrfs: use spread ssd " | |
191 | "allocation scheme\n"); | |
192 | btrfs_set_opt(info->mount_opt, SSD); | |
193 | btrfs_set_opt(info->mount_opt, SSD_SPREAD); | |
194 | break; | |
3b30c22f | 195 | case Opt_nossd: |
451d7585 CM |
196 | printk(KERN_INFO "btrfs: not using ssd allocation " |
197 | "scheme\n"); | |
c289811c | 198 | btrfs_set_opt(info->mount_opt, NOSSD); |
3b30c22f | 199 | btrfs_clear_opt(info->mount_opt, SSD); |
451d7585 | 200 | btrfs_clear_opt(info->mount_opt, SSD_SPREAD); |
3b30c22f | 201 | break; |
21ad10cf | 202 | case Opt_nobarrier: |
edf24abe CH |
203 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
204 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 205 | break; |
4543df7e CM |
206 | case Opt_thread_pool: |
207 | intarg = 0; | |
208 | match_int(&args[0], &intarg); | |
209 | if (intarg) { | |
210 | info->thread_pool_size = intarg; | |
211 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
212 | info->thread_pool_size); | |
213 | } | |
214 | break; | |
6f568d35 | 215 | case Opt_max_inline: |
edf24abe CH |
216 | num = match_strdup(&args[0]); |
217 | if (num) { | |
91748467 | 218 | info->max_inline = memparse(num, NULL); |
edf24abe CH |
219 | kfree(num); |
220 | ||
15ada040 CM |
221 | if (info->max_inline) { |
222 | info->max_inline = max_t(u64, | |
223 | info->max_inline, | |
224 | root->sectorsize); | |
225 | } | |
edf24abe | 226 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
21380931 | 227 | (unsigned long long)info->max_inline); |
6f568d35 CM |
228 | } |
229 | break; | |
8f662a76 | 230 | case Opt_alloc_start: |
edf24abe CH |
231 | num = match_strdup(&args[0]); |
232 | if (num) { | |
91748467 | 233 | info->alloc_start = memparse(num, NULL); |
edf24abe CH |
234 | kfree(num); |
235 | printk(KERN_INFO | |
236 | "btrfs: allocations start at %llu\n", | |
21380931 | 237 | (unsigned long long)info->alloc_start); |
8f662a76 CM |
238 | } |
239 | break; | |
33268eaf JB |
240 | case Opt_noacl: |
241 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
242 | break; | |
3a5e1404 SW |
243 | case Opt_notreelog: |
244 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
245 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
246 | break; | |
dccae999 SW |
247 | case Opt_flushoncommit: |
248 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
249 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
250 | break; | |
97e728d4 JB |
251 | case Opt_ratio: |
252 | intarg = 0; | |
253 | match_int(&args[0], &intarg); | |
254 | if (intarg) { | |
255 | info->metadata_ratio = intarg; | |
256 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
257 | info->metadata_ratio); | |
258 | } | |
259 | break; | |
e244a0ae CH |
260 | case Opt_discard: |
261 | btrfs_set_opt(info->mount_opt, DISCARD); | |
262 | break; | |
0af3d00b JB |
263 | case Opt_space_cache: |
264 | printk(KERN_INFO "btrfs: enabling disk space caching\n"); | |
265 | btrfs_set_opt(info->mount_opt, SPACE_CACHE); | |
0de90876 | 266 | break; |
88c2ba3b JB |
267 | case Opt_clear_cache: |
268 | printk(KERN_INFO "btrfs: force clearing of disk cache\n"); | |
269 | btrfs_set_opt(info->mount_opt, CLEAR_CACHE); | |
0af3d00b | 270 | break; |
4260f7c7 SW |
271 | case Opt_user_subvol_rm_allowed: |
272 | btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); | |
273 | break; | |
a7a3f7ca SW |
274 | case Opt_err: |
275 | printk(KERN_INFO "btrfs: unrecognized mount option " | |
276 | "'%s'\n", p); | |
277 | ret = -EINVAL; | |
278 | goto out; | |
95e05289 | 279 | default: |
be20aa9d | 280 | break; |
95e05289 CM |
281 | } |
282 | } | |
a7a3f7ca | 283 | out: |
da495ecc | 284 | kfree(orig); |
a7a3f7ca | 285 | return ret; |
edf24abe CH |
286 | } |
287 | ||
288 | /* | |
289 | * Parse mount options that are required early in the mount process. | |
290 | * | |
291 | * All other options will be parsed on much later in the mount process and | |
292 | * only when we need to allocate a new super block. | |
293 | */ | |
97288f2c | 294 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
73f73415 | 295 | void *holder, char **subvol_name, u64 *subvol_objectid, |
43e570b0 | 296 | struct btrfs_fs_devices **fs_devices) |
edf24abe CH |
297 | { |
298 | substring_t args[MAX_OPT_ARGS]; | |
299 | char *opts, *p; | |
300 | int error = 0; | |
73f73415 | 301 | int intarg; |
edf24abe CH |
302 | |
303 | if (!options) | |
304 | goto out; | |
305 | ||
306 | /* | |
307 | * strsep changes the string, duplicate it because parse_options | |
308 | * gets called twice | |
309 | */ | |
310 | opts = kstrdup(options, GFP_KERNEL); | |
311 | if (!opts) | |
312 | return -ENOMEM; | |
313 | ||
314 | while ((p = strsep(&opts, ",")) != NULL) { | |
315 | int token; | |
316 | if (!*p) | |
317 | continue; | |
318 | ||
319 | token = match_token(p, tokens, args); | |
320 | switch (token) { | |
321 | case Opt_subvol: | |
322 | *subvol_name = match_strdup(&args[0]); | |
323 | break; | |
73f73415 JB |
324 | case Opt_subvolid: |
325 | intarg = 0; | |
4849f01d JB |
326 | error = match_int(&args[0], &intarg); |
327 | if (!error) { | |
328 | /* we want the original fs_tree */ | |
329 | if (!intarg) | |
330 | *subvol_objectid = | |
331 | BTRFS_FS_TREE_OBJECTID; | |
332 | else | |
333 | *subvol_objectid = intarg; | |
334 | } | |
73f73415 | 335 | break; |
43e570b0 CH |
336 | case Opt_device: |
337 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
338 | flags, holder, fs_devices); | |
339 | if (error) | |
340 | goto out_free_opts; | |
341 | break; | |
edf24abe CH |
342 | default: |
343 | break; | |
344 | } | |
345 | } | |
346 | ||
43e570b0 | 347 | out_free_opts: |
edf24abe CH |
348 | kfree(opts); |
349 | out: | |
350 | /* | |
351 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 352 | * a copy of the string "." here so that code later in the |
edf24abe CH |
353 | * mount path doesn't care if it's the default volume or another one. |
354 | */ | |
355 | if (!*subvol_name) { | |
3de4586c | 356 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
357 | if (!*subvol_name) |
358 | return -ENOMEM; | |
359 | } | |
360 | return error; | |
95e05289 CM |
361 | } |
362 | ||
73f73415 JB |
363 | static struct dentry *get_default_root(struct super_block *sb, |
364 | u64 subvol_objectid) | |
365 | { | |
366 | struct btrfs_root *root = sb->s_fs_info; | |
367 | struct btrfs_root *new_root; | |
368 | struct btrfs_dir_item *di; | |
369 | struct btrfs_path *path; | |
370 | struct btrfs_key location; | |
371 | struct inode *inode; | |
372 | struct dentry *dentry; | |
373 | u64 dir_id; | |
374 | int new = 0; | |
375 | ||
376 | /* | |
377 | * We have a specific subvol we want to mount, just setup location and | |
378 | * go look up the root. | |
379 | */ | |
380 | if (subvol_objectid) { | |
381 | location.objectid = subvol_objectid; | |
382 | location.type = BTRFS_ROOT_ITEM_KEY; | |
383 | location.offset = (u64)-1; | |
384 | goto find_root; | |
385 | } | |
386 | ||
387 | path = btrfs_alloc_path(); | |
388 | if (!path) | |
389 | return ERR_PTR(-ENOMEM); | |
390 | path->leave_spinning = 1; | |
391 | ||
392 | /* | |
393 | * Find the "default" dir item which points to the root item that we | |
394 | * will mount by default if we haven't been given a specific subvolume | |
395 | * to mount. | |
396 | */ | |
397 | dir_id = btrfs_super_root_dir(&root->fs_info->super_copy); | |
398 | di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); | |
fb4f6f91 DC |
399 | if (IS_ERR(di)) |
400 | return ERR_CAST(di); | |
73f73415 JB |
401 | if (!di) { |
402 | /* | |
403 | * Ok the default dir item isn't there. This is weird since | |
404 | * it's always been there, but don't freak out, just try and | |
405 | * mount to root most subvolume. | |
406 | */ | |
407 | btrfs_free_path(path); | |
408 | dir_id = BTRFS_FIRST_FREE_OBJECTID; | |
409 | new_root = root->fs_info->fs_root; | |
410 | goto setup_root; | |
411 | } | |
412 | ||
413 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); | |
414 | btrfs_free_path(path); | |
415 | ||
416 | find_root: | |
417 | new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); | |
418 | if (IS_ERR(new_root)) | |
d0b678cb | 419 | return ERR_CAST(new_root); |
73f73415 JB |
420 | |
421 | if (btrfs_root_refs(&new_root->root_item) == 0) | |
422 | return ERR_PTR(-ENOENT); | |
423 | ||
424 | dir_id = btrfs_root_dirid(&new_root->root_item); | |
425 | setup_root: | |
426 | location.objectid = dir_id; | |
427 | location.type = BTRFS_INODE_ITEM_KEY; | |
428 | location.offset = 0; | |
429 | ||
430 | inode = btrfs_iget(sb, &location, new_root, &new); | |
4cbd1149 DC |
431 | if (IS_ERR(inode)) |
432 | return ERR_CAST(inode); | |
73f73415 JB |
433 | |
434 | /* | |
435 | * If we're just mounting the root most subvol put the inode and return | |
436 | * a reference to the dentry. We will have already gotten a reference | |
437 | * to the inode in btrfs_fill_super so we're good to go. | |
438 | */ | |
439 | if (!new && sb->s_root->d_inode == inode) { | |
440 | iput(inode); | |
441 | return dget(sb->s_root); | |
442 | } | |
443 | ||
444 | if (new) { | |
445 | const struct qstr name = { .name = "/", .len = 1 }; | |
446 | ||
447 | /* | |
448 | * New inode, we need to make the dentry a sibling of s_root so | |
449 | * everything gets cleaned up properly on unmount. | |
450 | */ | |
451 | dentry = d_alloc(sb->s_root, &name); | |
452 | if (!dentry) { | |
453 | iput(inode); | |
454 | return ERR_PTR(-ENOMEM); | |
455 | } | |
456 | d_splice_alias(inode, dentry); | |
457 | } else { | |
458 | /* | |
459 | * We found the inode in cache, just find a dentry for it and | |
460 | * put the reference to the inode we just got. | |
461 | */ | |
462 | dentry = d_find_alias(inode); | |
463 | iput(inode); | |
464 | } | |
465 | ||
466 | return dentry; | |
467 | } | |
468 | ||
d397712b | 469 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 470 | struct btrfs_fs_devices *fs_devices, |
d397712b | 471 | void *data, int silent) |
75dfe396 | 472 | { |
d397712b CM |
473 | struct inode *inode; |
474 | struct dentry *root_dentry; | |
39279cc3 | 475 | struct btrfs_root *tree_root; |
5d4f98a2 | 476 | struct btrfs_key key; |
39279cc3 | 477 | int err; |
a429e513 | 478 | |
39279cc3 CM |
479 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
480 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
481 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 482 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 483 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 484 | sb->s_time_gran = 1; |
0eda294d | 485 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
33268eaf | 486 | sb->s_flags |= MS_POSIXACL; |
49cf6f45 | 487 | #endif |
a429e513 | 488 | |
dfe25020 | 489 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 490 | |
e58ca020 | 491 | if (IS_ERR(tree_root)) { |
39279cc3 | 492 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 493 | return PTR_ERR(tree_root); |
a429e513 | 494 | } |
39279cc3 | 495 | sb->s_fs_info = tree_root; |
a429e513 | 496 | |
5d4f98a2 YZ |
497 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
498 | key.type = BTRFS_INODE_ITEM_KEY; | |
499 | key.offset = 0; | |
73f73415 | 500 | inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root, NULL); |
5d4f98a2 YZ |
501 | if (IS_ERR(inode)) { |
502 | err = PTR_ERR(inode); | |
39279cc3 | 503 | goto fail_close; |
f254e52c | 504 | } |
f254e52c | 505 | |
39279cc3 CM |
506 | root_dentry = d_alloc_root(inode); |
507 | if (!root_dentry) { | |
508 | iput(inode); | |
509 | err = -ENOMEM; | |
510 | goto fail_close; | |
f254e52c | 511 | } |
58176a96 | 512 | |
39279cc3 | 513 | sb->s_root = root_dentry; |
6885f308 | 514 | |
6885f308 | 515 | save_mount_options(sb, data); |
2619ba1f | 516 | return 0; |
39279cc3 CM |
517 | |
518 | fail_close: | |
519 | close_ctree(tree_root); | |
520 | return err; | |
2619ba1f CM |
521 | } |
522 | ||
6bf13c0c | 523 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
524 | { |
525 | struct btrfs_trans_handle *trans; | |
dccae999 | 526 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 527 | int ret; |
2619ba1f | 528 | |
39279cc3 CM |
529 | if (!wait) { |
530 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
531 | return 0; | |
532 | } | |
771ed689 | 533 | |
24bbcf04 YZ |
534 | btrfs_start_delalloc_inodes(root, 0); |
535 | btrfs_wait_ordered_extents(root, 0, 0); | |
771ed689 | 536 | |
a22285a6 | 537 | trans = btrfs_start_transaction(root, 0); |
c5739bba | 538 | ret = btrfs_commit_transaction(trans, root); |
54aa1f4d | 539 | return ret; |
2c90e5d6 CM |
540 | } |
541 | ||
a9572a15 EP |
542 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
543 | { | |
544 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
545 | struct btrfs_fs_info *info = root->fs_info; | |
546 | ||
547 | if (btrfs_test_opt(root, DEGRADED)) | |
548 | seq_puts(seq, ",degraded"); | |
549 | if (btrfs_test_opt(root, NODATASUM)) | |
550 | seq_puts(seq, ",nodatasum"); | |
551 | if (btrfs_test_opt(root, NODATACOW)) | |
552 | seq_puts(seq, ",nodatacow"); | |
553 | if (btrfs_test_opt(root, NOBARRIER)) | |
554 | seq_puts(seq, ",nobarrier"); | |
a9572a15 | 555 | if (info->max_inline != 8192 * 1024) |
21380931 JB |
556 | seq_printf(seq, ",max_inline=%llu", |
557 | (unsigned long long)info->max_inline); | |
a9572a15 | 558 | if (info->alloc_start != 0) |
21380931 JB |
559 | seq_printf(seq, ",alloc_start=%llu", |
560 | (unsigned long long)info->alloc_start); | |
a9572a15 EP |
561 | if (info->thread_pool_size != min_t(unsigned long, |
562 | num_online_cpus() + 2, 8)) | |
563 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
564 | if (btrfs_test_opt(root, COMPRESS)) | |
565 | seq_puts(seq, ",compress"); | |
c289811c CM |
566 | if (btrfs_test_opt(root, NOSSD)) |
567 | seq_puts(seq, ",nossd"); | |
451d7585 CM |
568 | if (btrfs_test_opt(root, SSD_SPREAD)) |
569 | seq_puts(seq, ",ssd_spread"); | |
570 | else if (btrfs_test_opt(root, SSD)) | |
a9572a15 | 571 | seq_puts(seq, ",ssd"); |
3a5e1404 | 572 | if (btrfs_test_opt(root, NOTREELOG)) |
6b65c5c6 | 573 | seq_puts(seq, ",notreelog"); |
dccae999 | 574 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
6b65c5c6 | 575 | seq_puts(seq, ",flushoncommit"); |
20a5239a MW |
576 | if (btrfs_test_opt(root, DISCARD)) |
577 | seq_puts(seq, ",discard"); | |
a9572a15 EP |
578 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
579 | seq_puts(seq, ",noacl"); | |
580 | return 0; | |
581 | } | |
582 | ||
a061fc8d | 583 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 584 | { |
450ba0ea | 585 | struct btrfs_root *test_root = data; |
a061fc8d | 586 | struct btrfs_root *root = btrfs_sb(s); |
4b82d6e4 | 587 | |
619c8c76 IK |
588 | /* |
589 | * If this super block is going away, return false as it | |
590 | * can't match as an existing super block. | |
591 | */ | |
592 | if (!atomic_read(&s->s_active)) | |
593 | return 0; | |
450ba0ea | 594 | return root->fs_info->fs_devices == test_root->fs_info->fs_devices; |
4b82d6e4 Y |
595 | } |
596 | ||
450ba0ea JB |
597 | static int btrfs_set_super(struct super_block *s, void *data) |
598 | { | |
599 | s->s_fs_info = data; | |
600 | ||
601 | return set_anon_super(s, data); | |
602 | } | |
603 | ||
604 | ||
edf24abe CH |
605 | /* |
606 | * Find a superblock for the given device / mount point. | |
607 | * | |
608 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
609 | * for multiple device setup. Make sure to keep it in sync. | |
610 | */ | |
611 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
612 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 Y |
613 | { |
614 | struct block_device *bdev = NULL; | |
615 | struct super_block *s; | |
616 | struct dentry *root; | |
8a4b83cc | 617 | struct btrfs_fs_devices *fs_devices = NULL; |
450ba0ea JB |
618 | struct btrfs_root *tree_root = NULL; |
619 | struct btrfs_fs_info *fs_info = NULL; | |
97288f2c | 620 | fmode_t mode = FMODE_READ; |
73f73415 JB |
621 | char *subvol_name = NULL; |
622 | u64 subvol_objectid = 0; | |
4b82d6e4 Y |
623 | int error = 0; |
624 | ||
97288f2c CH |
625 | if (!(flags & MS_RDONLY)) |
626 | mode |= FMODE_WRITE; | |
627 | ||
628 | error = btrfs_parse_early_options(data, mode, fs_type, | |
73f73415 JB |
629 | &subvol_name, &subvol_objectid, |
630 | &fs_devices); | |
edf24abe | 631 | if (error) |
1f483660 | 632 | return error; |
edf24abe | 633 | |
97288f2c | 634 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 635 | if (error) |
edf24abe | 636 | goto error_free_subvol_name; |
4b82d6e4 | 637 | |
97288f2c | 638 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 639 | if (error) |
edf24abe | 640 | goto error_free_subvol_name; |
8a4b83cc | 641 | |
2b82032c YZ |
642 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
643 | error = -EACCES; | |
644 | goto error_close_devices; | |
645 | } | |
646 | ||
450ba0ea JB |
647 | /* |
648 | * Setup a dummy root and fs_info for test/set super. This is because | |
649 | * we don't actually fill this stuff out until open_ctree, but we need | |
650 | * it for searching for existing supers, so this lets us do that and | |
651 | * then open_ctree will properly initialize everything later. | |
652 | */ | |
653 | fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS); | |
654 | tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS); | |
655 | if (!fs_info || !tree_root) { | |
656 | error = -ENOMEM; | |
657 | goto error_close_devices; | |
658 | } | |
659 | fs_info->tree_root = tree_root; | |
660 | fs_info->fs_devices = fs_devices; | |
661 | tree_root->fs_info = fs_info; | |
662 | ||
dfe25020 | 663 | bdev = fs_devices->latest_bdev; |
450ba0ea | 664 | s = sget(fs_type, btrfs_test_super, btrfs_set_super, tree_root); |
4b82d6e4 Y |
665 | if (IS_ERR(s)) |
666 | goto error_s; | |
667 | ||
668 | if (s->s_root) { | |
669 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
6f5bbff9 | 670 | deactivate_locked_super(s); |
4b82d6e4 | 671 | error = -EBUSY; |
c146afad | 672 | goto error_close_devices; |
4b82d6e4 Y |
673 | } |
674 | ||
2b82032c | 675 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
676 | } else { |
677 | char b[BDEVNAME_SIZE]; | |
678 | ||
679 | s->s_flags = flags; | |
680 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
681 | error = btrfs_fill_super(s, fs_devices, data, |
682 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 | 683 | if (error) { |
6f5bbff9 | 684 | deactivate_locked_super(s); |
1f483660 | 685 | goto error_free_subvol_name; |
4b82d6e4 Y |
686 | } |
687 | ||
788f20eb | 688 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
689 | s->s_flags |= MS_ACTIVE; |
690 | } | |
691 | ||
73f73415 JB |
692 | root = get_default_root(s, subvol_objectid); |
693 | if (IS_ERR(root)) { | |
694 | error = PTR_ERR(root); | |
695 | deactivate_locked_super(s); | |
0e78340f | 696 | goto error_free_subvol_name; |
73f73415 JB |
697 | } |
698 | /* if they gave us a subvolume name bind mount into that */ | |
699 | if (strcmp(subvol_name, ".")) { | |
700 | struct dentry *new_root; | |
701 | mutex_lock(&root->d_inode->i_mutex); | |
702 | new_root = lookup_one_len(subvol_name, root, | |
d397712b | 703 | strlen(subvol_name)); |
73f73415 | 704 | mutex_unlock(&root->d_inode->i_mutex); |
d397712b | 705 | |
73f73415 | 706 | if (IS_ERR(new_root)) { |
f106e82c | 707 | dput(root); |
6f5bbff9 | 708 | deactivate_locked_super(s); |
73f73415 | 709 | error = PTR_ERR(new_root); |
0e78340f | 710 | goto error_free_subvol_name; |
76fcef19 | 711 | } |
73f73415 | 712 | if (!new_root->d_inode) { |
76fcef19 | 713 | dput(root); |
73f73415 | 714 | dput(new_root); |
6f5bbff9 | 715 | deactivate_locked_super(s); |
76fcef19 | 716 | error = -ENXIO; |
0e78340f | 717 | goto error_free_subvol_name; |
76fcef19 | 718 | } |
73f73415 JB |
719 | dput(root); |
720 | root = new_root; | |
4b82d6e4 Y |
721 | } |
722 | ||
723 | mnt->mnt_sb = s; | |
724 | mnt->mnt_root = root; | |
edf24abe CH |
725 | |
726 | kfree(subvol_name); | |
4b82d6e4 Y |
727 | return 0; |
728 | ||
729 | error_s: | |
730 | error = PTR_ERR(s); | |
c146afad | 731 | error_close_devices: |
8a4b83cc | 732 | btrfs_close_devices(fs_devices); |
450ba0ea JB |
733 | kfree(fs_info); |
734 | kfree(tree_root); | |
edf24abe CH |
735 | error_free_subvol_name: |
736 | kfree(subvol_name); | |
4b82d6e4 Y |
737 | return error; |
738 | } | |
2e635a27 | 739 | |
c146afad YZ |
740 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
741 | { | |
742 | struct btrfs_root *root = btrfs_sb(sb); | |
743 | int ret; | |
744 | ||
b288052e CM |
745 | ret = btrfs_parse_options(root, data); |
746 | if (ret) | |
747 | return -EINVAL; | |
748 | ||
c146afad YZ |
749 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
750 | return 0; | |
751 | ||
752 | if (*flags & MS_RDONLY) { | |
753 | sb->s_flags |= MS_RDONLY; | |
754 | ||
755 | ret = btrfs_commit_super(root); | |
756 | WARN_ON(ret); | |
757 | } else { | |
2b82032c YZ |
758 | if (root->fs_info->fs_devices->rw_devices == 0) |
759 | return -EACCES; | |
760 | ||
c146afad YZ |
761 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
762 | return -EINVAL; | |
763 | ||
d68fc57b | 764 | ret = btrfs_cleanup_fs_roots(root->fs_info); |
c146afad YZ |
765 | WARN_ON(ret); |
766 | ||
d68fc57b YZ |
767 | /* recover relocation */ |
768 | ret = btrfs_recover_relocation(root); | |
c146afad YZ |
769 | WARN_ON(ret); |
770 | ||
771 | sb->s_flags &= ~MS_RDONLY; | |
772 | } | |
773 | ||
774 | return 0; | |
775 | } | |
776 | ||
8fd17795 CM |
777 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
778 | { | |
779 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 780 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
bd4d1088 JB |
781 | struct list_head *head = &root->fs_info->space_info; |
782 | struct btrfs_space_info *found; | |
783 | u64 total_used = 0; | |
89a55897 | 784 | u64 total_used_data = 0; |
db94535d | 785 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 786 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 | 787 | |
bd4d1088 | 788 | rcu_read_lock(); |
89a55897 JB |
789 | list_for_each_entry_rcu(found, head, list) { |
790 | if (found->flags & (BTRFS_BLOCK_GROUP_METADATA | | |
791 | BTRFS_BLOCK_GROUP_SYSTEM)) | |
792 | total_used_data += found->disk_total; | |
793 | else | |
794 | total_used_data += found->disk_used; | |
b742bb82 | 795 | total_used += found->disk_used; |
89a55897 | 796 | } |
bd4d1088 JB |
797 | rcu_read_unlock(); |
798 | ||
8fd17795 | 799 | buf->f_namelen = BTRFS_NAME_LEN; |
db94535d | 800 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
bd4d1088 | 801 | buf->f_bfree = buf->f_blocks - (total_used >> bits); |
89a55897 | 802 | buf->f_bavail = buf->f_blocks - (total_used_data >> bits); |
8fd17795 CM |
803 | buf->f_bsize = dentry->d_sb->s_blocksize; |
804 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 805 | |
9d03632e | 806 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 807 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
808 | on a big-endian or little-endian host */ |
809 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
810 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
811 | /* Mask in the root object ID too, to disambiguate subvols */ |
812 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
813 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
814 | ||
8fd17795 CM |
815 | return 0; |
816 | } | |
b5133862 | 817 | |
2e635a27 CM |
818 | static struct file_system_type btrfs_fs_type = { |
819 | .owner = THIS_MODULE, | |
820 | .name = "btrfs", | |
821 | .get_sb = btrfs_get_sb, | |
a061fc8d | 822 | .kill_sb = kill_anon_super, |
2e635a27 CM |
823 | .fs_flags = FS_REQUIRES_DEV, |
824 | }; | |
a9218f6b | 825 | |
d352ac68 CM |
826 | /* |
827 | * used by btrfsctl to scan devices when no FS is mounted | |
828 | */ | |
8a4b83cc CM |
829 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
830 | unsigned long arg) | |
831 | { | |
832 | struct btrfs_ioctl_vol_args *vol; | |
833 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 834 | int ret = -ENOTTY; |
8a4b83cc | 835 | |
e441d54d CM |
836 | if (!capable(CAP_SYS_ADMIN)) |
837 | return -EPERM; | |
838 | ||
dae7b665 LZ |
839 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
840 | if (IS_ERR(vol)) | |
841 | return PTR_ERR(vol); | |
c071fcfd | 842 | |
8a4b83cc CM |
843 | switch (cmd) { |
844 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 845 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
846 | &btrfs_fs_type, &fs_devices); |
847 | break; | |
848 | } | |
dae7b665 | 849 | |
8a4b83cc | 850 | kfree(vol); |
f819d837 | 851 | return ret; |
8a4b83cc CM |
852 | } |
853 | ||
0176260f | 854 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
855 | { |
856 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
857 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
858 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 859 | return 0; |
ed0dab6b Y |
860 | } |
861 | ||
0176260f | 862 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
863 | { |
864 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
865 | mutex_unlock(&root->fs_info->cleaner_mutex); |
866 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 867 | return 0; |
ed0dab6b | 868 | } |
2e635a27 | 869 | |
b87221de | 870 | static const struct super_operations btrfs_super_ops = { |
76dda93c | 871 | .drop_inode = btrfs_drop_inode, |
bd555975 | 872 | .evict_inode = btrfs_evict_inode, |
e20d96d6 | 873 | .put_super = btrfs_put_super, |
d5719762 | 874 | .sync_fs = btrfs_sync_fs, |
a9572a15 | 875 | .show_options = btrfs_show_options, |
4730a4bc | 876 | .write_inode = btrfs_write_inode, |
b5133862 | 877 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
878 | .alloc_inode = btrfs_alloc_inode, |
879 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 880 | .statfs = btrfs_statfs, |
c146afad | 881 | .remount_fs = btrfs_remount, |
0176260f LT |
882 | .freeze_fs = btrfs_freeze, |
883 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 884 | }; |
a9218f6b CM |
885 | |
886 | static const struct file_operations btrfs_ctl_fops = { | |
887 | .unlocked_ioctl = btrfs_control_ioctl, | |
888 | .compat_ioctl = btrfs_control_ioctl, | |
889 | .owner = THIS_MODULE, | |
890 | }; | |
891 | ||
892 | static struct miscdevice btrfs_misc = { | |
578454ff | 893 | .minor = BTRFS_MINOR, |
a9218f6b CM |
894 | .name = "btrfs-control", |
895 | .fops = &btrfs_ctl_fops | |
896 | }; | |
897 | ||
578454ff KS |
898 | MODULE_ALIAS_MISCDEV(BTRFS_MINOR); |
899 | MODULE_ALIAS("devname:btrfs-control"); | |
900 | ||
a9218f6b CM |
901 | static int btrfs_interface_init(void) |
902 | { | |
903 | return misc_register(&btrfs_misc); | |
904 | } | |
905 | ||
b2950863 | 906 | static void btrfs_interface_exit(void) |
a9218f6b CM |
907 | { |
908 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 909 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
910 | } |
911 | ||
2e635a27 CM |
912 | static int __init init_btrfs_fs(void) |
913 | { | |
2c90e5d6 | 914 | int err; |
58176a96 JB |
915 | |
916 | err = btrfs_init_sysfs(); | |
917 | if (err) | |
918 | return err; | |
919 | ||
261507a0 | 920 | err = btrfs_init_compress(); |
2c90e5d6 | 921 | if (err) |
a74a4b97 | 922 | goto free_sysfs; |
d1310b2e | 923 | |
261507a0 LZ |
924 | err = btrfs_init_cachep(); |
925 | if (err) | |
926 | goto free_compress; | |
927 | ||
d1310b2e | 928 | err = extent_io_init(); |
2f4cbe64 WB |
929 | if (err) |
930 | goto free_cachep; | |
931 | ||
d1310b2e CM |
932 | err = extent_map_init(); |
933 | if (err) | |
934 | goto free_extent_io; | |
935 | ||
a9218f6b | 936 | err = btrfs_interface_init(); |
2f4cbe64 WB |
937 | if (err) |
938 | goto free_extent_map; | |
c8b97818 | 939 | |
a9218f6b CM |
940 | err = register_filesystem(&btrfs_fs_type); |
941 | if (err) | |
942 | goto unregister_ioctl; | |
b3c3da71 CM |
943 | |
944 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
945 | return 0; |
946 | ||
a9218f6b CM |
947 | unregister_ioctl: |
948 | btrfs_interface_exit(); | |
2f4cbe64 WB |
949 | free_extent_map: |
950 | extent_map_exit(); | |
d1310b2e CM |
951 | free_extent_io: |
952 | extent_io_exit(); | |
2f4cbe64 WB |
953 | free_cachep: |
954 | btrfs_destroy_cachep(); | |
261507a0 LZ |
955 | free_compress: |
956 | btrfs_exit_compress(); | |
a74a4b97 | 957 | free_sysfs: |
2f4cbe64 WB |
958 | btrfs_exit_sysfs(); |
959 | return err; | |
2e635a27 CM |
960 | } |
961 | ||
962 | static void __exit exit_btrfs_fs(void) | |
963 | { | |
39279cc3 | 964 | btrfs_destroy_cachep(); |
a52d9a80 | 965 | extent_map_exit(); |
d1310b2e | 966 | extent_io_exit(); |
a9218f6b | 967 | btrfs_interface_exit(); |
2e635a27 | 968 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 969 | btrfs_exit_sysfs(); |
8a4b83cc | 970 | btrfs_cleanup_fs_uuids(); |
261507a0 | 971 | btrfs_exit_compress(); |
2e635a27 CM |
972 | } |
973 | ||
974 | module_init(init_btrfs_fs) | |
975 | module_exit(exit_btrfs_fs) | |
976 | ||
977 | MODULE_LICENSE("GPL"); |