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