Commit | Line | Data |
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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> |
4b4e25f2 | 41 | #include "compat.h" |
2e635a27 | 42 | #include "ctree.h" |
e20d96d6 | 43 | #include "disk-io.h" |
d5719762 | 44 | #include "transaction.h" |
2c90e5d6 | 45 | #include "btrfs_inode.h" |
c5739bba | 46 | #include "ioctl.h" |
3a686375 | 47 | #include "print-tree.h" |
5103e947 | 48 | #include "xattr.h" |
8a4b83cc | 49 | #include "volumes.h" |
b3c3da71 | 50 | #include "version.h" |
be6e8dc0 | 51 | #include "export.h" |
c8b97818 | 52 | #include "compression.h" |
2e635a27 | 53 | |
b87221de | 54 | static const struct super_operations btrfs_super_ops; |
75dfe396 | 55 | |
d397712b | 56 | static void btrfs_put_super(struct super_block *sb) |
b18c6685 | 57 | { |
39279cc3 | 58 | struct btrfs_root *root = btrfs_sb(sb); |
b18c6685 | 59 | int ret; |
b18c6685 | 60 | |
39279cc3 | 61 | ret = close_ctree(root); |
39279cc3 | 62 | sb->s_fs_info = NULL; |
75dfe396 CM |
63 | } |
64 | ||
95e05289 | 65 | enum { |
43e570b0 | 66 | Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, |
dfe25020 | 67 | Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, |
451d7585 | 68 | Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, |
e244a0ae CH |
69 | Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit, |
70 | Opt_discard, Opt_err, | |
95e05289 CM |
71 | }; |
72 | ||
73 | static match_table_t tokens = { | |
dfe25020 | 74 | {Opt_degraded, "degraded"}, |
95e05289 | 75 | {Opt_subvol, "subvol=%s"}, |
43e570b0 | 76 | {Opt_device, "device=%s"}, |
b6cda9bc | 77 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 78 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 79 | {Opt_nobarrier, "nobarrier"}, |
c59f8951 | 80 | {Opt_max_extent, "max_extent=%s"}, |
6f568d35 | 81 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 82 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 83 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 84 | {Opt_compress, "compress"}, |
e18e4809 | 85 | {Opt_ssd, "ssd"}, |
451d7585 | 86 | {Opt_ssd_spread, "ssd_spread"}, |
3b30c22f | 87 | {Opt_nossd, "nossd"}, |
33268eaf | 88 | {Opt_noacl, "noacl"}, |
3a5e1404 | 89 | {Opt_notreelog, "notreelog"}, |
dccae999 | 90 | {Opt_flushoncommit, "flushoncommit"}, |
97e728d4 | 91 | {Opt_ratio, "metadata_ratio=%d"}, |
e244a0ae | 92 | {Opt_discard, "discard"}, |
33268eaf | 93 | {Opt_err, NULL}, |
95e05289 CM |
94 | }; |
95 | ||
edbd8d4e | 96 | u64 btrfs_parse_size(char *str) |
c59f8951 | 97 | { |
edbd8d4e | 98 | u64 res; |
c59f8951 CM |
99 | int mult = 1; |
100 | char *end; | |
101 | char last; | |
102 | ||
103 | res = simple_strtoul(str, &end, 10); | |
104 | ||
105 | last = end[0]; | |
106 | if (isalpha(last)) { | |
107 | last = tolower(last); | |
108 | switch (last) { | |
109 | case 'g': | |
110 | mult *= 1024; | |
111 | case 'm': | |
112 | mult *= 1024; | |
113 | case 'k': | |
114 | mult *= 1024; | |
115 | } | |
116 | res = res * mult; | |
117 | } | |
118 | return res; | |
119 | } | |
120 | ||
edf24abe CH |
121 | /* |
122 | * Regular mount options parser. Everything that is needed only when | |
123 | * reading in a new superblock is parsed here. | |
124 | */ | |
125 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 126 | { |
edf24abe | 127 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 128 | substring_t args[MAX_OPT_ARGS]; |
edf24abe | 129 | char *p, *num; |
4543df7e | 130 | int intarg; |
b6cda9bc | 131 | |
95e05289 | 132 | if (!options) |
edf24abe | 133 | return 0; |
95e05289 | 134 | |
be20aa9d CM |
135 | /* |
136 | * strsep changes the string, duplicate it because parse_options | |
137 | * gets called twice | |
138 | */ | |
139 | options = kstrdup(options, GFP_NOFS); | |
140 | if (!options) | |
141 | return -ENOMEM; | |
142 | ||
be20aa9d | 143 | |
edf24abe | 144 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
145 | int token; |
146 | if (!*p) | |
147 | continue; | |
148 | ||
149 | token = match_token(p, tokens, args); | |
150 | switch (token) { | |
dfe25020 | 151 | case Opt_degraded: |
edf24abe CH |
152 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
153 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 154 | break; |
95e05289 | 155 | case Opt_subvol: |
43e570b0 | 156 | case Opt_device: |
edf24abe | 157 | /* |
43e570b0 | 158 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
159 | * and can be happily ignored here. |
160 | */ | |
b6cda9bc CM |
161 | break; |
162 | case Opt_nodatasum: | |
067c28ad | 163 | printk(KERN_INFO "btrfs: setting nodatasum\n"); |
edf24abe | 164 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
165 | break; |
166 | case Opt_nodatacow: | |
edf24abe CH |
167 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
168 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
169 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 170 | break; |
c8b97818 CM |
171 | case Opt_compress: |
172 | printk(KERN_INFO "btrfs: use compression\n"); | |
173 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
174 | break; | |
e18e4809 | 175 | case Opt_ssd: |
edf24abe CH |
176 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
177 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 178 | break; |
451d7585 CM |
179 | case Opt_ssd_spread: |
180 | printk(KERN_INFO "btrfs: use spread ssd " | |
181 | "allocation scheme\n"); | |
182 | btrfs_set_opt(info->mount_opt, SSD); | |
183 | btrfs_set_opt(info->mount_opt, SSD_SPREAD); | |
184 | break; | |
3b30c22f | 185 | case Opt_nossd: |
451d7585 CM |
186 | printk(KERN_INFO "btrfs: not using ssd allocation " |
187 | "scheme\n"); | |
c289811c | 188 | btrfs_set_opt(info->mount_opt, NOSSD); |
3b30c22f | 189 | btrfs_clear_opt(info->mount_opt, SSD); |
451d7585 | 190 | btrfs_clear_opt(info->mount_opt, SSD_SPREAD); |
3b30c22f | 191 | break; |
21ad10cf | 192 | case Opt_nobarrier: |
edf24abe CH |
193 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
194 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 195 | break; |
4543df7e CM |
196 | case Opt_thread_pool: |
197 | intarg = 0; | |
198 | match_int(&args[0], &intarg); | |
199 | if (intarg) { | |
200 | info->thread_pool_size = intarg; | |
201 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
202 | info->thread_pool_size); | |
203 | } | |
204 | break; | |
c59f8951 | 205 | case Opt_max_extent: |
edf24abe CH |
206 | num = match_strdup(&args[0]); |
207 | if (num) { | |
208 | info->max_extent = btrfs_parse_size(num); | |
209 | kfree(num); | |
210 | ||
211 | info->max_extent = max_t(u64, | |
212 | info->max_extent, root->sectorsize); | |
213 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
21380931 | 214 | (unsigned long long)info->max_extent); |
c59f8951 CM |
215 | } |
216 | break; | |
6f568d35 | 217 | case Opt_max_inline: |
edf24abe CH |
218 | num = match_strdup(&args[0]); |
219 | if (num) { | |
220 | info->max_inline = btrfs_parse_size(num); | |
221 | kfree(num); | |
222 | ||
15ada040 CM |
223 | if (info->max_inline) { |
224 | info->max_inline = max_t(u64, | |
225 | info->max_inline, | |
226 | root->sectorsize); | |
227 | } | |
edf24abe | 228 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
21380931 | 229 | (unsigned long long)info->max_inline); |
6f568d35 CM |
230 | } |
231 | break; | |
8f662a76 | 232 | case Opt_alloc_start: |
edf24abe CH |
233 | num = match_strdup(&args[0]); |
234 | if (num) { | |
235 | info->alloc_start = btrfs_parse_size(num); | |
236 | kfree(num); | |
237 | printk(KERN_INFO | |
238 | "btrfs: allocations start at %llu\n", | |
21380931 | 239 | (unsigned long long)info->alloc_start); |
8f662a76 CM |
240 | } |
241 | break; | |
33268eaf JB |
242 | case Opt_noacl: |
243 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
244 | break; | |
3a5e1404 SW |
245 | case Opt_notreelog: |
246 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
247 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
248 | break; | |
dccae999 SW |
249 | case Opt_flushoncommit: |
250 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
251 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
252 | break; | |
97e728d4 JB |
253 | case Opt_ratio: |
254 | intarg = 0; | |
255 | match_int(&args[0], &intarg); | |
256 | if (intarg) { | |
257 | info->metadata_ratio = intarg; | |
258 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
259 | info->metadata_ratio); | |
260 | } | |
261 | break; | |
e244a0ae CH |
262 | case Opt_discard: |
263 | btrfs_set_opt(info->mount_opt, DISCARD); | |
264 | break; | |
95e05289 | 265 | default: |
be20aa9d | 266 | break; |
95e05289 CM |
267 | } |
268 | } | |
be20aa9d | 269 | kfree(options); |
edf24abe CH |
270 | return 0; |
271 | } | |
272 | ||
273 | /* | |
274 | * Parse mount options that are required early in the mount process. | |
275 | * | |
276 | * All other options will be parsed on much later in the mount process and | |
277 | * only when we need to allocate a new super block. | |
278 | */ | |
97288f2c | 279 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
43e570b0 CH |
280 | void *holder, char **subvol_name, |
281 | struct btrfs_fs_devices **fs_devices) | |
edf24abe CH |
282 | { |
283 | substring_t args[MAX_OPT_ARGS]; | |
284 | char *opts, *p; | |
285 | int error = 0; | |
286 | ||
287 | if (!options) | |
288 | goto out; | |
289 | ||
290 | /* | |
291 | * strsep changes the string, duplicate it because parse_options | |
292 | * gets called twice | |
293 | */ | |
294 | opts = kstrdup(options, GFP_KERNEL); | |
295 | if (!opts) | |
296 | return -ENOMEM; | |
297 | ||
298 | while ((p = strsep(&opts, ",")) != NULL) { | |
299 | int token; | |
300 | if (!*p) | |
301 | continue; | |
302 | ||
303 | token = match_token(p, tokens, args); | |
304 | switch (token) { | |
305 | case Opt_subvol: | |
306 | *subvol_name = match_strdup(&args[0]); | |
307 | break; | |
43e570b0 CH |
308 | case Opt_device: |
309 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
310 | flags, holder, fs_devices); | |
311 | if (error) | |
312 | goto out_free_opts; | |
313 | break; | |
edf24abe CH |
314 | default: |
315 | break; | |
316 | } | |
317 | } | |
318 | ||
43e570b0 | 319 | out_free_opts: |
edf24abe CH |
320 | kfree(opts); |
321 | out: | |
322 | /* | |
323 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 324 | * a copy of the string "." here so that code later in the |
edf24abe CH |
325 | * mount path doesn't care if it's the default volume or another one. |
326 | */ | |
327 | if (!*subvol_name) { | |
3de4586c | 328 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
329 | if (!*subvol_name) |
330 | return -ENOMEM; | |
331 | } | |
332 | return error; | |
95e05289 CM |
333 | } |
334 | ||
d397712b | 335 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 336 | struct btrfs_fs_devices *fs_devices, |
d397712b | 337 | void *data, int silent) |
75dfe396 | 338 | { |
d397712b CM |
339 | struct inode *inode; |
340 | struct dentry *root_dentry; | |
39279cc3 CM |
341 | struct btrfs_super_block *disk_super; |
342 | struct btrfs_root *tree_root; | |
5d4f98a2 | 343 | struct btrfs_key key; |
39279cc3 | 344 | int err; |
a429e513 | 345 | |
39279cc3 CM |
346 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
347 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
348 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 349 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 350 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 351 | sb->s_time_gran = 1; |
0eda294d | 352 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
33268eaf | 353 | sb->s_flags |= MS_POSIXACL; |
49cf6f45 | 354 | #endif |
a429e513 | 355 | |
dfe25020 | 356 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 357 | |
e58ca020 | 358 | if (IS_ERR(tree_root)) { |
39279cc3 | 359 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 360 | return PTR_ERR(tree_root); |
a429e513 | 361 | } |
39279cc3 | 362 | sb->s_fs_info = tree_root; |
5f39d397 | 363 | disk_super = &tree_root->fs_info->super_copy; |
a429e513 | 364 | |
5d4f98a2 YZ |
365 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
366 | key.type = BTRFS_INODE_ITEM_KEY; | |
367 | key.offset = 0; | |
368 | inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root); | |
369 | if (IS_ERR(inode)) { | |
370 | err = PTR_ERR(inode); | |
39279cc3 | 371 | goto fail_close; |
f254e52c | 372 | } |
f254e52c | 373 | |
39279cc3 CM |
374 | root_dentry = d_alloc_root(inode); |
375 | if (!root_dentry) { | |
376 | iput(inode); | |
377 | err = -ENOMEM; | |
378 | goto fail_close; | |
f254e52c | 379 | } |
e4404d6e | 380 | #if 0 |
58176a96 JB |
381 | /* this does the super kobj at the same time */ |
382 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
383 | if (err) | |
384 | goto fail_close; | |
e4404d6e | 385 | #endif |
58176a96 | 386 | |
39279cc3 | 387 | sb->s_root = root_dentry; |
6885f308 | 388 | |
6885f308 | 389 | save_mount_options(sb, data); |
2619ba1f | 390 | return 0; |
39279cc3 CM |
391 | |
392 | fail_close: | |
393 | close_ctree(tree_root); | |
394 | return err; | |
2619ba1f CM |
395 | } |
396 | ||
6bf13c0c | 397 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
398 | { |
399 | struct btrfs_trans_handle *trans; | |
dccae999 | 400 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 401 | int ret; |
2619ba1f | 402 | |
39279cc3 CM |
403 | if (!wait) { |
404 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
405 | return 0; | |
406 | } | |
771ed689 | 407 | |
24bbcf04 YZ |
408 | btrfs_start_delalloc_inodes(root, 0); |
409 | btrfs_wait_ordered_extents(root, 0, 0); | |
771ed689 | 410 | |
c5739bba | 411 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 412 | ret = btrfs_commit_transaction(trans, root); |
54aa1f4d | 413 | return ret; |
2c90e5d6 CM |
414 | } |
415 | ||
a9572a15 EP |
416 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
417 | { | |
418 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
419 | struct btrfs_fs_info *info = root->fs_info; | |
420 | ||
421 | if (btrfs_test_opt(root, DEGRADED)) | |
422 | seq_puts(seq, ",degraded"); | |
423 | if (btrfs_test_opt(root, NODATASUM)) | |
424 | seq_puts(seq, ",nodatasum"); | |
425 | if (btrfs_test_opt(root, NODATACOW)) | |
426 | seq_puts(seq, ",nodatacow"); | |
427 | if (btrfs_test_opt(root, NOBARRIER)) | |
428 | seq_puts(seq, ",nobarrier"); | |
429 | if (info->max_extent != (u64)-1) | |
21380931 JB |
430 | seq_printf(seq, ",max_extent=%llu", |
431 | (unsigned long long)info->max_extent); | |
a9572a15 | 432 | if (info->max_inline != 8192 * 1024) |
21380931 JB |
433 | seq_printf(seq, ",max_inline=%llu", |
434 | (unsigned long long)info->max_inline); | |
a9572a15 | 435 | if (info->alloc_start != 0) |
21380931 JB |
436 | seq_printf(seq, ",alloc_start=%llu", |
437 | (unsigned long long)info->alloc_start); | |
a9572a15 EP |
438 | if (info->thread_pool_size != min_t(unsigned long, |
439 | num_online_cpus() + 2, 8)) | |
440 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
441 | if (btrfs_test_opt(root, COMPRESS)) | |
442 | seq_puts(seq, ",compress"); | |
c289811c CM |
443 | if (btrfs_test_opt(root, NOSSD)) |
444 | seq_puts(seq, ",nossd"); | |
451d7585 CM |
445 | if (btrfs_test_opt(root, SSD_SPREAD)) |
446 | seq_puts(seq, ",ssd_spread"); | |
447 | else if (btrfs_test_opt(root, SSD)) | |
a9572a15 | 448 | seq_puts(seq, ",ssd"); |
3a5e1404 | 449 | if (btrfs_test_opt(root, NOTREELOG)) |
6b65c5c6 | 450 | seq_puts(seq, ",notreelog"); |
dccae999 | 451 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
6b65c5c6 | 452 | seq_puts(seq, ",flushoncommit"); |
a9572a15 EP |
453 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
454 | seq_puts(seq, ",noacl"); | |
455 | return 0; | |
456 | } | |
457 | ||
a061fc8d | 458 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 459 | { |
a061fc8d CM |
460 | struct btrfs_fs_devices *test_fs_devices = data; |
461 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 462 | |
a061fc8d | 463 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
464 | } |
465 | ||
edf24abe CH |
466 | /* |
467 | * Find a superblock for the given device / mount point. | |
468 | * | |
469 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
470 | * for multiple device setup. Make sure to keep it in sync. | |
471 | */ | |
472 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
473 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 474 | { |
edf24abe | 475 | char *subvol_name = NULL; |
4b82d6e4 Y |
476 | struct block_device *bdev = NULL; |
477 | struct super_block *s; | |
478 | struct dentry *root; | |
8a4b83cc | 479 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 480 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
481 | int error = 0; |
482 | ||
97288f2c CH |
483 | if (!(flags & MS_RDONLY)) |
484 | mode |= FMODE_WRITE; | |
485 | ||
486 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 487 | &subvol_name, &fs_devices); |
edf24abe | 488 | if (error) |
1f483660 | 489 | return error; |
edf24abe | 490 | |
97288f2c | 491 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 492 | if (error) |
edf24abe | 493 | goto error_free_subvol_name; |
4b82d6e4 | 494 | |
97288f2c | 495 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 496 | if (error) |
edf24abe | 497 | goto error_free_subvol_name; |
8a4b83cc | 498 | |
2b82032c YZ |
499 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
500 | error = -EACCES; | |
501 | goto error_close_devices; | |
502 | } | |
503 | ||
dfe25020 | 504 | bdev = fs_devices->latest_bdev; |
a061fc8d | 505 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
506 | if (IS_ERR(s)) |
507 | goto error_s; | |
508 | ||
509 | if (s->s_root) { | |
510 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
6f5bbff9 | 511 | deactivate_locked_super(s); |
4b82d6e4 | 512 | error = -EBUSY; |
c146afad | 513 | goto error_close_devices; |
4b82d6e4 Y |
514 | } |
515 | ||
2b82032c | 516 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
517 | } else { |
518 | char b[BDEVNAME_SIZE]; | |
519 | ||
520 | s->s_flags = flags; | |
521 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
522 | error = btrfs_fill_super(s, fs_devices, data, |
523 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 | 524 | if (error) { |
6f5bbff9 | 525 | deactivate_locked_super(s); |
1f483660 | 526 | goto error_free_subvol_name; |
4b82d6e4 Y |
527 | } |
528 | ||
788f20eb | 529 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
530 | s->s_flags |= MS_ACTIVE; |
531 | } | |
532 | ||
76fcef19 DW |
533 | if (!strcmp(subvol_name, ".")) |
534 | root = dget(s->s_root); | |
535 | else { | |
536 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
d397712b CM |
537 | root = lookup_one_len(subvol_name, s->s_root, |
538 | strlen(subvol_name)); | |
76fcef19 | 539 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
d397712b | 540 | |
76fcef19 | 541 | if (IS_ERR(root)) { |
6f5bbff9 | 542 | deactivate_locked_super(s); |
76fcef19 | 543 | error = PTR_ERR(root); |
1f483660 | 544 | goto error_free_subvol_name; |
76fcef19 DW |
545 | } |
546 | if (!root->d_inode) { | |
547 | dput(root); | |
6f5bbff9 | 548 | deactivate_locked_super(s); |
76fcef19 | 549 | error = -ENXIO; |
1f483660 | 550 | goto error_free_subvol_name; |
76fcef19 | 551 | } |
4b82d6e4 Y |
552 | } |
553 | ||
554 | mnt->mnt_sb = s; | |
555 | mnt->mnt_root = root; | |
edf24abe CH |
556 | |
557 | kfree(subvol_name); | |
4b82d6e4 Y |
558 | return 0; |
559 | ||
560 | error_s: | |
561 | error = PTR_ERR(s); | |
c146afad | 562 | error_close_devices: |
8a4b83cc | 563 | btrfs_close_devices(fs_devices); |
edf24abe CH |
564 | error_free_subvol_name: |
565 | kfree(subvol_name); | |
4b82d6e4 Y |
566 | return error; |
567 | } | |
2e635a27 | 568 | |
c146afad YZ |
569 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
570 | { | |
571 | struct btrfs_root *root = btrfs_sb(sb); | |
572 | int ret; | |
573 | ||
b288052e CM |
574 | ret = btrfs_parse_options(root, data); |
575 | if (ret) | |
576 | return -EINVAL; | |
577 | ||
c146afad YZ |
578 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
579 | return 0; | |
580 | ||
581 | if (*flags & MS_RDONLY) { | |
582 | sb->s_flags |= MS_RDONLY; | |
583 | ||
584 | ret = btrfs_commit_super(root); | |
585 | WARN_ON(ret); | |
586 | } else { | |
2b82032c YZ |
587 | if (root->fs_info->fs_devices->rw_devices == 0) |
588 | return -EACCES; | |
589 | ||
c146afad YZ |
590 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
591 | return -EINVAL; | |
592 | ||
5d4f98a2 YZ |
593 | /* recover relocation */ |
594 | ret = btrfs_recover_relocation(root); | |
c146afad YZ |
595 | WARN_ON(ret); |
596 | ||
597 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
598 | WARN_ON(ret); | |
599 | ||
600 | sb->s_flags &= ~MS_RDONLY; | |
601 | } | |
602 | ||
603 | return 0; | |
604 | } | |
605 | ||
8fd17795 CM |
606 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
607 | { | |
608 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 609 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 610 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 611 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
612 | |
613 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
614 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
615 | buf->f_bfree = buf->f_blocks - | |
616 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
617 | buf->f_bavail = buf->f_bfree; |
618 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
619 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 620 | |
9d03632e | 621 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 622 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
623 | on a big-endian or little-endian host */ |
624 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
625 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
626 | /* Mask in the root object ID too, to disambiguate subvols */ |
627 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
628 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
629 | ||
8fd17795 CM |
630 | return 0; |
631 | } | |
b5133862 | 632 | |
2e635a27 CM |
633 | static struct file_system_type btrfs_fs_type = { |
634 | .owner = THIS_MODULE, | |
635 | .name = "btrfs", | |
636 | .get_sb = btrfs_get_sb, | |
a061fc8d | 637 | .kill_sb = kill_anon_super, |
2e635a27 CM |
638 | .fs_flags = FS_REQUIRES_DEV, |
639 | }; | |
a9218f6b | 640 | |
d352ac68 CM |
641 | /* |
642 | * used by btrfsctl to scan devices when no FS is mounted | |
643 | */ | |
8a4b83cc CM |
644 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
645 | unsigned long arg) | |
646 | { | |
647 | struct btrfs_ioctl_vol_args *vol; | |
648 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 649 | int ret = -ENOTTY; |
8a4b83cc | 650 | |
e441d54d CM |
651 | if (!capable(CAP_SYS_ADMIN)) |
652 | return -EPERM; | |
653 | ||
dae7b665 LZ |
654 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
655 | if (IS_ERR(vol)) | |
656 | return PTR_ERR(vol); | |
c071fcfd | 657 | |
8a4b83cc CM |
658 | switch (cmd) { |
659 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 660 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
661 | &btrfs_fs_type, &fs_devices); |
662 | break; | |
663 | } | |
dae7b665 | 664 | |
8a4b83cc | 665 | kfree(vol); |
f819d837 | 666 | return ret; |
8a4b83cc CM |
667 | } |
668 | ||
0176260f | 669 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
670 | { |
671 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
672 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
673 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 674 | return 0; |
ed0dab6b Y |
675 | } |
676 | ||
0176260f | 677 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
678 | { |
679 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
680 | mutex_unlock(&root->fs_info->cleaner_mutex); |
681 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 682 | return 0; |
ed0dab6b | 683 | } |
2e635a27 | 684 | |
b87221de | 685 | static const struct super_operations btrfs_super_ops = { |
76dda93c | 686 | .drop_inode = btrfs_drop_inode, |
134e9731 | 687 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 688 | .put_super = btrfs_put_super, |
d5719762 | 689 | .sync_fs = btrfs_sync_fs, |
a9572a15 | 690 | .show_options = btrfs_show_options, |
4730a4bc | 691 | .write_inode = btrfs_write_inode, |
b5133862 | 692 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
693 | .alloc_inode = btrfs_alloc_inode, |
694 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 695 | .statfs = btrfs_statfs, |
c146afad | 696 | .remount_fs = btrfs_remount, |
0176260f LT |
697 | .freeze_fs = btrfs_freeze, |
698 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 699 | }; |
a9218f6b CM |
700 | |
701 | static const struct file_operations btrfs_ctl_fops = { | |
702 | .unlocked_ioctl = btrfs_control_ioctl, | |
703 | .compat_ioctl = btrfs_control_ioctl, | |
704 | .owner = THIS_MODULE, | |
705 | }; | |
706 | ||
707 | static struct miscdevice btrfs_misc = { | |
708 | .minor = MISC_DYNAMIC_MINOR, | |
709 | .name = "btrfs-control", | |
710 | .fops = &btrfs_ctl_fops | |
711 | }; | |
712 | ||
713 | static int btrfs_interface_init(void) | |
714 | { | |
715 | return misc_register(&btrfs_misc); | |
716 | } | |
717 | ||
b2950863 | 718 | static void btrfs_interface_exit(void) |
a9218f6b CM |
719 | { |
720 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 721 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
722 | } |
723 | ||
2e635a27 CM |
724 | static int __init init_btrfs_fs(void) |
725 | { | |
2c90e5d6 | 726 | int err; |
58176a96 JB |
727 | |
728 | err = btrfs_init_sysfs(); | |
729 | if (err) | |
730 | return err; | |
731 | ||
39279cc3 | 732 | err = btrfs_init_cachep(); |
2c90e5d6 | 733 | if (err) |
a74a4b97 | 734 | goto free_sysfs; |
d1310b2e CM |
735 | |
736 | err = extent_io_init(); | |
2f4cbe64 WB |
737 | if (err) |
738 | goto free_cachep; | |
739 | ||
d1310b2e CM |
740 | err = extent_map_init(); |
741 | if (err) | |
742 | goto free_extent_io; | |
743 | ||
a9218f6b | 744 | err = btrfs_interface_init(); |
2f4cbe64 WB |
745 | if (err) |
746 | goto free_extent_map; | |
c8b97818 | 747 | |
a9218f6b CM |
748 | err = register_filesystem(&btrfs_fs_type); |
749 | if (err) | |
750 | goto unregister_ioctl; | |
b3c3da71 CM |
751 | |
752 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
753 | return 0; |
754 | ||
a9218f6b CM |
755 | unregister_ioctl: |
756 | btrfs_interface_exit(); | |
2f4cbe64 WB |
757 | free_extent_map: |
758 | extent_map_exit(); | |
d1310b2e CM |
759 | free_extent_io: |
760 | extent_io_exit(); | |
2f4cbe64 WB |
761 | free_cachep: |
762 | btrfs_destroy_cachep(); | |
a74a4b97 | 763 | free_sysfs: |
2f4cbe64 WB |
764 | btrfs_exit_sysfs(); |
765 | return err; | |
2e635a27 CM |
766 | } |
767 | ||
768 | static void __exit exit_btrfs_fs(void) | |
769 | { | |
39279cc3 | 770 | btrfs_destroy_cachep(); |
a52d9a80 | 771 | extent_map_exit(); |
d1310b2e | 772 | extent_io_exit(); |
a9218f6b | 773 | btrfs_interface_exit(); |
2e635a27 | 774 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 775 | btrfs_exit_sysfs(); |
8a4b83cc | 776 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 777 | btrfs_zlib_exit(); |
2e635a27 CM |
778 | } |
779 | ||
780 | module_init(init_btrfs_fs) | |
781 | module_exit(exit_btrfs_fs) | |
782 | ||
783 | MODULE_LICENSE("GPL"); |