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 CM |
28 | #include <linux/string.h> |
29 | #include <linux/smp_lock.h> | |
30 | #include <linux/backing-dev.h> | |
4b82d6e4 | 31 | #include <linux/mount.h> |
dee26a9f | 32 | #include <linux/mpage.h> |
75dfe396 CM |
33 | #include <linux/swap.h> |
34 | #include <linux/writeback.h> | |
8fd17795 | 35 | #include <linux/statfs.h> |
08607c1b | 36 | #include <linux/compat.h> |
95e05289 | 37 | #include <linux/parser.h> |
c59f8951 | 38 | #include <linux/ctype.h> |
6da6abae | 39 | #include <linux/namei.h> |
a9218f6b | 40 | #include <linux/miscdevice.h> |
1bcbf313 | 41 | #include <linux/magic.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 | |
39279cc3 | 55 | static 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; |
75dfe396 CM |
64 | } |
65 | ||
95e05289 | 66 | enum { |
43e570b0 | 67 | Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, |
dfe25020 | 68 | Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, |
451d7585 CM |
69 | Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, |
70 | Opt_compress, Opt_notreelog, Opt_ratio, Opt_flushoncommit, 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"}, |
33268eaf | 92 | {Opt_err, NULL}, |
95e05289 CM |
93 | }; |
94 | ||
edbd8d4e | 95 | u64 btrfs_parse_size(char *str) |
c59f8951 | 96 | { |
edbd8d4e | 97 | u64 res; |
c59f8951 CM |
98 | int mult = 1; |
99 | char *end; | |
100 | char last; | |
101 | ||
102 | res = simple_strtoul(str, &end, 10); | |
103 | ||
104 | last = end[0]; | |
105 | if (isalpha(last)) { | |
106 | last = tolower(last); | |
107 | switch (last) { | |
108 | case 'g': | |
109 | mult *= 1024; | |
110 | case 'm': | |
111 | mult *= 1024; | |
112 | case 'k': | |
113 | mult *= 1024; | |
114 | } | |
115 | res = res * mult; | |
116 | } | |
117 | return res; | |
118 | } | |
119 | ||
edf24abe CH |
120 | /* |
121 | * Regular mount options parser. Everything that is needed only when | |
122 | * reading in a new superblock is parsed here. | |
123 | */ | |
124 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 125 | { |
edf24abe | 126 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 127 | substring_t args[MAX_OPT_ARGS]; |
edf24abe | 128 | char *p, *num; |
4543df7e | 129 | int intarg; |
b6cda9bc | 130 | |
95e05289 | 131 | if (!options) |
edf24abe | 132 | return 0; |
95e05289 | 133 | |
be20aa9d CM |
134 | /* |
135 | * strsep changes the string, duplicate it because parse_options | |
136 | * gets called twice | |
137 | */ | |
138 | options = kstrdup(options, GFP_NOFS); | |
139 | if (!options) | |
140 | return -ENOMEM; | |
141 | ||
be20aa9d | 142 | |
edf24abe | 143 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
144 | int token; |
145 | if (!*p) | |
146 | continue; | |
147 | ||
148 | token = match_token(p, tokens, args); | |
149 | switch (token) { | |
dfe25020 | 150 | case Opt_degraded: |
edf24abe CH |
151 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
152 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 153 | break; |
95e05289 | 154 | case Opt_subvol: |
43e570b0 | 155 | case Opt_device: |
edf24abe | 156 | /* |
43e570b0 | 157 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
158 | * and can be happily ignored here. |
159 | */ | |
b6cda9bc CM |
160 | break; |
161 | case Opt_nodatasum: | |
067c28ad | 162 | printk(KERN_INFO "btrfs: setting nodatasum\n"); |
edf24abe | 163 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
164 | break; |
165 | case Opt_nodatacow: | |
edf24abe CH |
166 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
167 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
168 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 169 | break; |
c8b97818 CM |
170 | case Opt_compress: |
171 | printk(KERN_INFO "btrfs: use compression\n"); | |
172 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
173 | break; | |
e18e4809 | 174 | case Opt_ssd: |
edf24abe CH |
175 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
176 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 177 | break; |
451d7585 CM |
178 | case Opt_ssd_spread: |
179 | printk(KERN_INFO "btrfs: use spread ssd " | |
180 | "allocation scheme\n"); | |
181 | btrfs_set_opt(info->mount_opt, SSD); | |
182 | btrfs_set_opt(info->mount_opt, SSD_SPREAD); | |
183 | break; | |
3b30c22f | 184 | case Opt_nossd: |
451d7585 CM |
185 | printk(KERN_INFO "btrfs: not using ssd allocation " |
186 | "scheme\n"); | |
c289811c | 187 | btrfs_set_opt(info->mount_opt, NOSSD); |
3b30c22f | 188 | btrfs_clear_opt(info->mount_opt, SSD); |
451d7585 | 189 | btrfs_clear_opt(info->mount_opt, SSD_SPREAD); |
3b30c22f | 190 | break; |
21ad10cf | 191 | case Opt_nobarrier: |
edf24abe CH |
192 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
193 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 194 | break; |
4543df7e CM |
195 | case Opt_thread_pool: |
196 | intarg = 0; | |
197 | match_int(&args[0], &intarg); | |
198 | if (intarg) { | |
199 | info->thread_pool_size = intarg; | |
200 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
201 | info->thread_pool_size); | |
202 | } | |
203 | break; | |
c59f8951 | 204 | case Opt_max_extent: |
edf24abe CH |
205 | num = match_strdup(&args[0]); |
206 | if (num) { | |
207 | info->max_extent = btrfs_parse_size(num); | |
208 | kfree(num); | |
209 | ||
210 | info->max_extent = max_t(u64, | |
211 | info->max_extent, root->sectorsize); | |
212 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
21380931 | 213 | (unsigned long long)info->max_extent); |
c59f8951 CM |
214 | } |
215 | break; | |
6f568d35 | 216 | case Opt_max_inline: |
edf24abe CH |
217 | num = match_strdup(&args[0]); |
218 | if (num) { | |
219 | info->max_inline = btrfs_parse_size(num); | |
220 | kfree(num); | |
221 | ||
15ada040 CM |
222 | if (info->max_inline) { |
223 | info->max_inline = max_t(u64, | |
224 | info->max_inline, | |
225 | root->sectorsize); | |
226 | } | |
edf24abe | 227 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
21380931 | 228 | (unsigned long long)info->max_inline); |
6f568d35 CM |
229 | } |
230 | break; | |
8f662a76 | 231 | case Opt_alloc_start: |
edf24abe CH |
232 | num = match_strdup(&args[0]); |
233 | if (num) { | |
234 | info->alloc_start = btrfs_parse_size(num); | |
235 | kfree(num); | |
236 | printk(KERN_INFO | |
237 | "btrfs: allocations start at %llu\n", | |
21380931 | 238 | (unsigned long long)info->alloc_start); |
8f662a76 CM |
239 | } |
240 | break; | |
33268eaf JB |
241 | case Opt_noacl: |
242 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
243 | break; | |
3a5e1404 SW |
244 | case Opt_notreelog: |
245 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
246 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
247 | break; | |
dccae999 SW |
248 | case Opt_flushoncommit: |
249 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
250 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
251 | break; | |
97e728d4 JB |
252 | case Opt_ratio: |
253 | intarg = 0; | |
254 | match_int(&args[0], &intarg); | |
255 | if (intarg) { | |
256 | info->metadata_ratio = intarg; | |
257 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
258 | info->metadata_ratio); | |
259 | } | |
260 | break; | |
95e05289 | 261 | default: |
be20aa9d | 262 | break; |
95e05289 CM |
263 | } |
264 | } | |
be20aa9d | 265 | kfree(options); |
edf24abe CH |
266 | return 0; |
267 | } | |
268 | ||
269 | /* | |
270 | * Parse mount options that are required early in the mount process. | |
271 | * | |
272 | * All other options will be parsed on much later in the mount process and | |
273 | * only when we need to allocate a new super block. | |
274 | */ | |
97288f2c | 275 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
43e570b0 CH |
276 | void *holder, char **subvol_name, |
277 | struct btrfs_fs_devices **fs_devices) | |
edf24abe CH |
278 | { |
279 | substring_t args[MAX_OPT_ARGS]; | |
280 | char *opts, *p; | |
281 | int error = 0; | |
282 | ||
283 | if (!options) | |
284 | goto out; | |
285 | ||
286 | /* | |
287 | * strsep changes the string, duplicate it because parse_options | |
288 | * gets called twice | |
289 | */ | |
290 | opts = kstrdup(options, GFP_KERNEL); | |
291 | if (!opts) | |
292 | return -ENOMEM; | |
293 | ||
294 | while ((p = strsep(&opts, ",")) != NULL) { | |
295 | int token; | |
296 | if (!*p) | |
297 | continue; | |
298 | ||
299 | token = match_token(p, tokens, args); | |
300 | switch (token) { | |
301 | case Opt_subvol: | |
302 | *subvol_name = match_strdup(&args[0]); | |
303 | break; | |
43e570b0 CH |
304 | case Opt_device: |
305 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
306 | flags, holder, fs_devices); | |
307 | if (error) | |
308 | goto out_free_opts; | |
309 | break; | |
edf24abe CH |
310 | default: |
311 | break; | |
312 | } | |
313 | } | |
314 | ||
43e570b0 | 315 | out_free_opts: |
edf24abe CH |
316 | kfree(opts); |
317 | out: | |
318 | /* | |
319 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 320 | * a copy of the string "." here so that code later in the |
edf24abe CH |
321 | * mount path doesn't care if it's the default volume or another one. |
322 | */ | |
323 | if (!*subvol_name) { | |
3de4586c | 324 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
325 | if (!*subvol_name) |
326 | return -ENOMEM; | |
327 | } | |
328 | return error; | |
95e05289 CM |
329 | } |
330 | ||
d397712b | 331 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 332 | struct btrfs_fs_devices *fs_devices, |
d397712b | 333 | void *data, int silent) |
75dfe396 | 334 | { |
d397712b CM |
335 | struct inode *inode; |
336 | struct dentry *root_dentry; | |
39279cc3 CM |
337 | struct btrfs_super_block *disk_super; |
338 | struct btrfs_root *tree_root; | |
5d4f98a2 | 339 | struct btrfs_key key; |
39279cc3 | 340 | int err; |
a429e513 | 341 | |
39279cc3 CM |
342 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
343 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
344 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 345 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 346 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 347 | sb->s_time_gran = 1; |
33268eaf | 348 | sb->s_flags |= MS_POSIXACL; |
a429e513 | 349 | |
dfe25020 | 350 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 351 | |
e58ca020 | 352 | if (IS_ERR(tree_root)) { |
39279cc3 | 353 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 354 | return PTR_ERR(tree_root); |
a429e513 | 355 | } |
39279cc3 | 356 | sb->s_fs_info = tree_root; |
5f39d397 | 357 | disk_super = &tree_root->fs_info->super_copy; |
a429e513 | 358 | |
5d4f98a2 YZ |
359 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
360 | key.type = BTRFS_INODE_ITEM_KEY; | |
361 | key.offset = 0; | |
362 | inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root); | |
363 | if (IS_ERR(inode)) { | |
364 | err = PTR_ERR(inode); | |
39279cc3 | 365 | goto fail_close; |
f254e52c | 366 | } |
f254e52c | 367 | |
39279cc3 CM |
368 | root_dentry = d_alloc_root(inode); |
369 | if (!root_dentry) { | |
370 | iput(inode); | |
371 | err = -ENOMEM; | |
372 | goto fail_close; | |
f254e52c | 373 | } |
e4404d6e | 374 | #if 0 |
58176a96 JB |
375 | /* this does the super kobj at the same time */ |
376 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
377 | if (err) | |
378 | goto fail_close; | |
e4404d6e | 379 | #endif |
58176a96 | 380 | |
39279cc3 | 381 | sb->s_root = root_dentry; |
6885f308 | 382 | |
6885f308 | 383 | save_mount_options(sb, data); |
2619ba1f | 384 | return 0; |
39279cc3 CM |
385 | |
386 | fail_close: | |
387 | close_ctree(tree_root); | |
388 | return err; | |
2619ba1f CM |
389 | } |
390 | ||
6bf13c0c | 391 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
392 | { |
393 | struct btrfs_trans_handle *trans; | |
dccae999 | 394 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 395 | int ret; |
2619ba1f | 396 | |
39279cc3 CM |
397 | if (!wait) { |
398 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
399 | return 0; | |
400 | } | |
771ed689 CM |
401 | |
402 | btrfs_start_delalloc_inodes(root); | |
403 | btrfs_wait_ordered_extents(root, 0); | |
404 | ||
c5739bba | 405 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 406 | ret = btrfs_commit_transaction(trans, root); |
54aa1f4d | 407 | return ret; |
2c90e5d6 CM |
408 | } |
409 | ||
a9572a15 EP |
410 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
411 | { | |
412 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
413 | struct btrfs_fs_info *info = root->fs_info; | |
414 | ||
415 | if (btrfs_test_opt(root, DEGRADED)) | |
416 | seq_puts(seq, ",degraded"); | |
417 | if (btrfs_test_opt(root, NODATASUM)) | |
418 | seq_puts(seq, ",nodatasum"); | |
419 | if (btrfs_test_opt(root, NODATACOW)) | |
420 | seq_puts(seq, ",nodatacow"); | |
421 | if (btrfs_test_opt(root, NOBARRIER)) | |
422 | seq_puts(seq, ",nobarrier"); | |
423 | if (info->max_extent != (u64)-1) | |
21380931 JB |
424 | seq_printf(seq, ",max_extent=%llu", |
425 | (unsigned long long)info->max_extent); | |
a9572a15 | 426 | if (info->max_inline != 8192 * 1024) |
21380931 JB |
427 | seq_printf(seq, ",max_inline=%llu", |
428 | (unsigned long long)info->max_inline); | |
a9572a15 | 429 | if (info->alloc_start != 0) |
21380931 JB |
430 | seq_printf(seq, ",alloc_start=%llu", |
431 | (unsigned long long)info->alloc_start); | |
a9572a15 EP |
432 | if (info->thread_pool_size != min_t(unsigned long, |
433 | num_online_cpus() + 2, 8)) | |
434 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
435 | if (btrfs_test_opt(root, COMPRESS)) | |
436 | seq_puts(seq, ",compress"); | |
c289811c CM |
437 | if (btrfs_test_opt(root, NOSSD)) |
438 | seq_puts(seq, ",nossd"); | |
451d7585 CM |
439 | if (btrfs_test_opt(root, SSD_SPREAD)) |
440 | seq_puts(seq, ",ssd_spread"); | |
441 | else if (btrfs_test_opt(root, SSD)) | |
a9572a15 | 442 | seq_puts(seq, ",ssd"); |
3a5e1404 | 443 | if (btrfs_test_opt(root, NOTREELOG)) |
6b65c5c6 | 444 | seq_puts(seq, ",notreelog"); |
dccae999 | 445 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
6b65c5c6 | 446 | seq_puts(seq, ",flushoncommit"); |
a9572a15 EP |
447 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
448 | seq_puts(seq, ",noacl"); | |
449 | return 0; | |
450 | } | |
451 | ||
a061fc8d | 452 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 453 | { |
a061fc8d CM |
454 | struct btrfs_fs_devices *test_fs_devices = data; |
455 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 456 | |
a061fc8d | 457 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
458 | } |
459 | ||
edf24abe CH |
460 | /* |
461 | * Find a superblock for the given device / mount point. | |
462 | * | |
463 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
464 | * for multiple device setup. Make sure to keep it in sync. | |
465 | */ | |
466 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
467 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 468 | { |
edf24abe | 469 | char *subvol_name = NULL; |
4b82d6e4 Y |
470 | struct block_device *bdev = NULL; |
471 | struct super_block *s; | |
472 | struct dentry *root; | |
8a4b83cc | 473 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 474 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
475 | int error = 0; |
476 | ||
97288f2c CH |
477 | if (!(flags & MS_RDONLY)) |
478 | mode |= FMODE_WRITE; | |
479 | ||
480 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 481 | &subvol_name, &fs_devices); |
edf24abe | 482 | if (error) |
1f483660 | 483 | return error; |
edf24abe | 484 | |
97288f2c | 485 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 486 | if (error) |
edf24abe | 487 | goto error_free_subvol_name; |
4b82d6e4 | 488 | |
97288f2c | 489 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 490 | if (error) |
edf24abe | 491 | goto error_free_subvol_name; |
8a4b83cc | 492 | |
2b82032c YZ |
493 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
494 | error = -EACCES; | |
495 | goto error_close_devices; | |
496 | } | |
497 | ||
dfe25020 | 498 | bdev = fs_devices->latest_bdev; |
a061fc8d | 499 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
500 | if (IS_ERR(s)) |
501 | goto error_s; | |
502 | ||
503 | if (s->s_root) { | |
504 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
6f5bbff9 | 505 | deactivate_locked_super(s); |
4b82d6e4 | 506 | error = -EBUSY; |
c146afad | 507 | goto error_close_devices; |
4b82d6e4 Y |
508 | } |
509 | ||
2b82032c | 510 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
511 | } else { |
512 | char b[BDEVNAME_SIZE]; | |
513 | ||
514 | s->s_flags = flags; | |
515 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
516 | error = btrfs_fill_super(s, fs_devices, data, |
517 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 | 518 | if (error) { |
6f5bbff9 | 519 | deactivate_locked_super(s); |
1f483660 | 520 | goto error_free_subvol_name; |
4b82d6e4 Y |
521 | } |
522 | ||
788f20eb | 523 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
524 | s->s_flags |= MS_ACTIVE; |
525 | } | |
526 | ||
76fcef19 DW |
527 | if (!strcmp(subvol_name, ".")) |
528 | root = dget(s->s_root); | |
529 | else { | |
530 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
d397712b CM |
531 | root = lookup_one_len(subvol_name, s->s_root, |
532 | strlen(subvol_name)); | |
76fcef19 | 533 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
d397712b | 534 | |
76fcef19 | 535 | if (IS_ERR(root)) { |
6f5bbff9 | 536 | deactivate_locked_super(s); |
76fcef19 | 537 | error = PTR_ERR(root); |
1f483660 | 538 | goto error_free_subvol_name; |
76fcef19 DW |
539 | } |
540 | if (!root->d_inode) { | |
541 | dput(root); | |
6f5bbff9 | 542 | deactivate_locked_super(s); |
76fcef19 | 543 | error = -ENXIO; |
1f483660 | 544 | goto error_free_subvol_name; |
76fcef19 | 545 | } |
4b82d6e4 Y |
546 | } |
547 | ||
548 | mnt->mnt_sb = s; | |
549 | mnt->mnt_root = root; | |
edf24abe CH |
550 | |
551 | kfree(subvol_name); | |
4b82d6e4 Y |
552 | return 0; |
553 | ||
554 | error_s: | |
555 | error = PTR_ERR(s); | |
c146afad | 556 | error_close_devices: |
8a4b83cc | 557 | btrfs_close_devices(fs_devices); |
edf24abe CH |
558 | error_free_subvol_name: |
559 | kfree(subvol_name); | |
4b82d6e4 Y |
560 | return error; |
561 | } | |
2e635a27 | 562 | |
c146afad YZ |
563 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
564 | { | |
565 | struct btrfs_root *root = btrfs_sb(sb); | |
566 | int ret; | |
567 | ||
b288052e CM |
568 | ret = btrfs_parse_options(root, data); |
569 | if (ret) | |
570 | return -EINVAL; | |
571 | ||
c146afad YZ |
572 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
573 | return 0; | |
574 | ||
575 | if (*flags & MS_RDONLY) { | |
576 | sb->s_flags |= MS_RDONLY; | |
577 | ||
578 | ret = btrfs_commit_super(root); | |
579 | WARN_ON(ret); | |
580 | } else { | |
2b82032c YZ |
581 | if (root->fs_info->fs_devices->rw_devices == 0) |
582 | return -EACCES; | |
583 | ||
c146afad YZ |
584 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
585 | return -EINVAL; | |
586 | ||
5d4f98a2 YZ |
587 | /* recover relocation */ |
588 | ret = btrfs_recover_relocation(root); | |
c146afad YZ |
589 | WARN_ON(ret); |
590 | ||
591 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
592 | WARN_ON(ret); | |
593 | ||
594 | sb->s_flags &= ~MS_RDONLY; | |
595 | } | |
596 | ||
597 | return 0; | |
598 | } | |
599 | ||
8fd17795 CM |
600 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
601 | { | |
602 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 603 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 604 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 605 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
606 | |
607 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
608 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
609 | buf->f_bfree = buf->f_blocks - | |
610 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
611 | buf->f_bavail = buf->f_bfree; |
612 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
613 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 614 | |
9d03632e | 615 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 616 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
617 | on a big-endian or little-endian host */ |
618 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
619 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
620 | /* Mask in the root object ID too, to disambiguate subvols */ |
621 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
622 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
623 | ||
8fd17795 CM |
624 | return 0; |
625 | } | |
b5133862 | 626 | |
2e635a27 CM |
627 | static struct file_system_type btrfs_fs_type = { |
628 | .owner = THIS_MODULE, | |
629 | .name = "btrfs", | |
630 | .get_sb = btrfs_get_sb, | |
a061fc8d | 631 | .kill_sb = kill_anon_super, |
2e635a27 CM |
632 | .fs_flags = FS_REQUIRES_DEV, |
633 | }; | |
a9218f6b | 634 | |
d352ac68 CM |
635 | /* |
636 | * used by btrfsctl to scan devices when no FS is mounted | |
637 | */ | |
8a4b83cc CM |
638 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
639 | unsigned long arg) | |
640 | { | |
641 | struct btrfs_ioctl_vol_args *vol; | |
642 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 643 | int ret = -ENOTTY; |
8a4b83cc | 644 | |
e441d54d CM |
645 | if (!capable(CAP_SYS_ADMIN)) |
646 | return -EPERM; | |
647 | ||
dae7b665 LZ |
648 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
649 | if (IS_ERR(vol)) | |
650 | return PTR_ERR(vol); | |
c071fcfd | 651 | |
8a4b83cc CM |
652 | switch (cmd) { |
653 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 654 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
655 | &btrfs_fs_type, &fs_devices); |
656 | break; | |
657 | } | |
dae7b665 | 658 | |
8a4b83cc | 659 | kfree(vol); |
f819d837 | 660 | return ret; |
8a4b83cc CM |
661 | } |
662 | ||
0176260f | 663 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
664 | { |
665 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
666 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
667 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 668 | return 0; |
ed0dab6b Y |
669 | } |
670 | ||
0176260f | 671 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
672 | { |
673 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
674 | mutex_unlock(&root->fs_info->cleaner_mutex); |
675 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 676 | return 0; |
ed0dab6b | 677 | } |
2e635a27 | 678 | |
e20d96d6 | 679 | static struct super_operations btrfs_super_ops = { |
134e9731 | 680 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 681 | .put_super = btrfs_put_super, |
d5719762 | 682 | .sync_fs = btrfs_sync_fs, |
a9572a15 | 683 | .show_options = btrfs_show_options, |
4730a4bc | 684 | .write_inode = btrfs_write_inode, |
b5133862 | 685 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
686 | .alloc_inode = btrfs_alloc_inode, |
687 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 688 | .statfs = btrfs_statfs, |
c146afad | 689 | .remount_fs = btrfs_remount, |
0176260f LT |
690 | .freeze_fs = btrfs_freeze, |
691 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 692 | }; |
a9218f6b CM |
693 | |
694 | static const struct file_operations btrfs_ctl_fops = { | |
695 | .unlocked_ioctl = btrfs_control_ioctl, | |
696 | .compat_ioctl = btrfs_control_ioctl, | |
697 | .owner = THIS_MODULE, | |
698 | }; | |
699 | ||
700 | static struct miscdevice btrfs_misc = { | |
701 | .minor = MISC_DYNAMIC_MINOR, | |
702 | .name = "btrfs-control", | |
703 | .fops = &btrfs_ctl_fops | |
704 | }; | |
705 | ||
706 | static int btrfs_interface_init(void) | |
707 | { | |
708 | return misc_register(&btrfs_misc); | |
709 | } | |
710 | ||
b2950863 | 711 | static void btrfs_interface_exit(void) |
a9218f6b CM |
712 | { |
713 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 714 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
715 | } |
716 | ||
2e635a27 CM |
717 | static int __init init_btrfs_fs(void) |
718 | { | |
2c90e5d6 | 719 | int err; |
58176a96 JB |
720 | |
721 | err = btrfs_init_sysfs(); | |
722 | if (err) | |
723 | return err; | |
724 | ||
39279cc3 | 725 | err = btrfs_init_cachep(); |
2c90e5d6 | 726 | if (err) |
a74a4b97 | 727 | goto free_sysfs; |
d1310b2e CM |
728 | |
729 | err = extent_io_init(); | |
2f4cbe64 WB |
730 | if (err) |
731 | goto free_cachep; | |
732 | ||
d1310b2e CM |
733 | err = extent_map_init(); |
734 | if (err) | |
735 | goto free_extent_io; | |
736 | ||
a9218f6b | 737 | err = btrfs_interface_init(); |
2f4cbe64 WB |
738 | if (err) |
739 | goto free_extent_map; | |
c8b97818 | 740 | |
a9218f6b CM |
741 | err = register_filesystem(&btrfs_fs_type); |
742 | if (err) | |
743 | goto unregister_ioctl; | |
b3c3da71 CM |
744 | |
745 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
746 | return 0; |
747 | ||
a9218f6b CM |
748 | unregister_ioctl: |
749 | btrfs_interface_exit(); | |
2f4cbe64 WB |
750 | free_extent_map: |
751 | extent_map_exit(); | |
d1310b2e CM |
752 | free_extent_io: |
753 | extent_io_exit(); | |
2f4cbe64 WB |
754 | free_cachep: |
755 | btrfs_destroy_cachep(); | |
a74a4b97 | 756 | free_sysfs: |
2f4cbe64 WB |
757 | btrfs_exit_sysfs(); |
758 | return err; | |
2e635a27 CM |
759 | } |
760 | ||
761 | static void __exit exit_btrfs_fs(void) | |
762 | { | |
39279cc3 | 763 | btrfs_destroy_cachep(); |
a52d9a80 | 764 | extent_map_exit(); |
d1310b2e | 765 | extent_io_exit(); |
a9218f6b | 766 | btrfs_interface_exit(); |
2e635a27 | 767 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 768 | btrfs_exit_sysfs(); |
8a4b83cc | 769 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 770 | btrfs_zlib_exit(); |
2e635a27 CM |
771 | } |
772 | ||
773 | module_init(init_btrfs_fs) | |
774 | module_exit(exit_btrfs_fs) | |
775 | ||
776 | MODULE_LICENSE("GPL"); |