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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> | |
27 | #include <linux/string.h> | |
28 | #include <linux/smp_lock.h> | |
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> |
4b4e25f2 CM |
40 | #include <linux/version.h> |
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 | |
5f39d397 | 54 | #define BTRFS_SUPER_MAGIC 0x9123683E |
f254e52c | 55 | |
39279cc3 | 56 | static struct super_operations btrfs_super_ops; |
75dfe396 | 57 | |
39279cc3 | 58 | static void btrfs_put_super (struct super_block * sb) |
b18c6685 | 59 | { |
39279cc3 | 60 | struct btrfs_root *root = btrfs_sb(sb); |
b18c6685 | 61 | int ret; |
b18c6685 | 62 | |
39279cc3 CM |
63 | ret = close_ctree(root); |
64 | if (ret) { | |
65 | printk("close ctree returns %d\n", ret); | |
75dfe396 | 66 | } |
e4404d6e YZ |
67 | #if 0 |
68 | btrfs_sysfs_del_super(root->fs_info); | |
69 | #endif | |
39279cc3 | 70 | sb->s_fs_info = NULL; |
75dfe396 CM |
71 | } |
72 | ||
95e05289 | 73 | enum { |
43e570b0 | 74 | Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, |
dfe25020 | 75 | Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, |
c8b97818 | 76 | Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_err, |
95e05289 CM |
77 | }; |
78 | ||
79 | static match_table_t tokens = { | |
dfe25020 | 80 | {Opt_degraded, "degraded"}, |
95e05289 | 81 | {Opt_subvol, "subvol=%s"}, |
43e570b0 | 82 | {Opt_device, "device=%s"}, |
b6cda9bc | 83 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 84 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 85 | {Opt_nobarrier, "nobarrier"}, |
c59f8951 | 86 | {Opt_max_extent, "max_extent=%s"}, |
6f568d35 | 87 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 88 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 89 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 90 | {Opt_compress, "compress"}, |
e18e4809 | 91 | {Opt_ssd, "ssd"}, |
33268eaf JB |
92 | {Opt_noacl, "noacl"}, |
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: | |
edf24abe CH |
163 | printk(KERN_INFO "btrfs: setting nodatacsum\n"); |
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; |
21ad10cf | 179 | case Opt_nobarrier: |
edf24abe CH |
180 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
181 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 182 | break; |
4543df7e CM |
183 | case Opt_thread_pool: |
184 | intarg = 0; | |
185 | match_int(&args[0], &intarg); | |
186 | if (intarg) { | |
187 | info->thread_pool_size = intarg; | |
188 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
189 | info->thread_pool_size); | |
190 | } | |
191 | break; | |
c59f8951 | 192 | case Opt_max_extent: |
edf24abe CH |
193 | num = match_strdup(&args[0]); |
194 | if (num) { | |
195 | info->max_extent = btrfs_parse_size(num); | |
196 | kfree(num); | |
197 | ||
198 | info->max_extent = max_t(u64, | |
199 | info->max_extent, root->sectorsize); | |
200 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
201 | info->max_extent); | |
c59f8951 CM |
202 | } |
203 | break; | |
6f568d35 | 204 | case Opt_max_inline: |
edf24abe CH |
205 | num = match_strdup(&args[0]); |
206 | if (num) { | |
207 | info->max_inline = btrfs_parse_size(num); | |
208 | kfree(num); | |
209 | ||
15ada040 CM |
210 | if (info->max_inline) { |
211 | info->max_inline = max_t(u64, | |
212 | info->max_inline, | |
213 | root->sectorsize); | |
214 | } | |
edf24abe CH |
215 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
216 | info->max_inline); | |
6f568d35 CM |
217 | } |
218 | break; | |
8f662a76 | 219 | case Opt_alloc_start: |
edf24abe CH |
220 | num = match_strdup(&args[0]); |
221 | if (num) { | |
222 | info->alloc_start = btrfs_parse_size(num); | |
223 | kfree(num); | |
224 | printk(KERN_INFO | |
225 | "btrfs: allocations start at %llu\n", | |
226 | info->alloc_start); | |
8f662a76 CM |
227 | } |
228 | break; | |
33268eaf JB |
229 | case Opt_noacl: |
230 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
231 | break; | |
95e05289 | 232 | default: |
be20aa9d | 233 | break; |
95e05289 CM |
234 | } |
235 | } | |
be20aa9d | 236 | kfree(options); |
edf24abe CH |
237 | return 0; |
238 | } | |
239 | ||
240 | /* | |
241 | * Parse mount options that are required early in the mount process. | |
242 | * | |
243 | * All other options will be parsed on much later in the mount process and | |
244 | * only when we need to allocate a new super block. | |
245 | */ | |
97288f2c | 246 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
43e570b0 CH |
247 | void *holder, char **subvol_name, |
248 | struct btrfs_fs_devices **fs_devices) | |
edf24abe CH |
249 | { |
250 | substring_t args[MAX_OPT_ARGS]; | |
251 | char *opts, *p; | |
252 | int error = 0; | |
253 | ||
254 | if (!options) | |
255 | goto out; | |
256 | ||
257 | /* | |
258 | * strsep changes the string, duplicate it because parse_options | |
259 | * gets called twice | |
260 | */ | |
261 | opts = kstrdup(options, GFP_KERNEL); | |
262 | if (!opts) | |
263 | return -ENOMEM; | |
264 | ||
265 | while ((p = strsep(&opts, ",")) != NULL) { | |
266 | int token; | |
267 | if (!*p) | |
268 | continue; | |
269 | ||
270 | token = match_token(p, tokens, args); | |
271 | switch (token) { | |
272 | case Opt_subvol: | |
273 | *subvol_name = match_strdup(&args[0]); | |
274 | break; | |
43e570b0 CH |
275 | case Opt_device: |
276 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
277 | flags, holder, fs_devices); | |
278 | if (error) | |
279 | goto out_free_opts; | |
280 | break; | |
edf24abe CH |
281 | default: |
282 | break; | |
283 | } | |
284 | } | |
285 | ||
43e570b0 | 286 | out_free_opts: |
edf24abe CH |
287 | kfree(opts); |
288 | out: | |
289 | /* | |
290 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 291 | * a copy of the string "." here so that code later in the |
edf24abe CH |
292 | * mount path doesn't care if it's the default volume or another one. |
293 | */ | |
294 | if (!*subvol_name) { | |
3de4586c | 295 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
296 | if (!*subvol_name) |
297 | return -ENOMEM; | |
298 | } | |
299 | return error; | |
95e05289 CM |
300 | } |
301 | ||
8a4b83cc CM |
302 | static int btrfs_fill_super(struct super_block * sb, |
303 | struct btrfs_fs_devices *fs_devices, | |
304 | void * data, int silent) | |
75dfe396 | 305 | { |
39279cc3 CM |
306 | struct inode * inode; |
307 | struct dentry * root_dentry; | |
308 | struct btrfs_super_block *disk_super; | |
309 | struct btrfs_root *tree_root; | |
310 | struct btrfs_inode *bi; | |
311 | int err; | |
a429e513 | 312 | |
39279cc3 CM |
313 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
314 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
315 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 316 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 317 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 318 | sb->s_time_gran = 1; |
33268eaf | 319 | sb->s_flags |= MS_POSIXACL; |
a429e513 | 320 | |
dfe25020 | 321 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 322 | |
e58ca020 | 323 | if (IS_ERR(tree_root)) { |
39279cc3 | 324 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 325 | return PTR_ERR(tree_root); |
a429e513 | 326 | } |
39279cc3 | 327 | sb->s_fs_info = tree_root; |
5f39d397 | 328 | disk_super = &tree_root->fs_info->super_copy; |
3de4586c CM |
329 | inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID, |
330 | tree_root->fs_info->fs_root); | |
39279cc3 CM |
331 | bi = BTRFS_I(inode); |
332 | bi->location.objectid = inode->i_ino; | |
333 | bi->location.offset = 0; | |
3de4586c | 334 | bi->root = tree_root->fs_info->fs_root; |
b888db2b | 335 | |
39279cc3 | 336 | btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY); |
a429e513 | 337 | |
39279cc3 | 338 | if (!inode) { |
6567e837 | 339 | err = -ENOMEM; |
39279cc3 | 340 | goto fail_close; |
f254e52c | 341 | } |
39279cc3 CM |
342 | if (inode->i_state & I_NEW) { |
343 | btrfs_read_locked_inode(inode); | |
344 | unlock_new_inode(inode); | |
f254e52c | 345 | } |
f254e52c | 346 | |
39279cc3 CM |
347 | root_dentry = d_alloc_root(inode); |
348 | if (!root_dentry) { | |
349 | iput(inode); | |
350 | err = -ENOMEM; | |
351 | goto fail_close; | |
f254e52c | 352 | } |
e4404d6e | 353 | #if 0 |
58176a96 JB |
354 | /* this does the super kobj at the same time */ |
355 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
356 | if (err) | |
357 | goto fail_close; | |
e4404d6e | 358 | #endif |
58176a96 | 359 | |
39279cc3 | 360 | sb->s_root = root_dentry; |
6885f308 | 361 | |
6885f308 | 362 | save_mount_options(sb, data); |
2619ba1f | 363 | return 0; |
39279cc3 CM |
364 | |
365 | fail_close: | |
366 | close_ctree(tree_root); | |
367 | return err; | |
2619ba1f CM |
368 | } |
369 | ||
6bf13c0c | 370 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
371 | { |
372 | struct btrfs_trans_handle *trans; | |
39279cc3 | 373 | struct btrfs_root *root; |
c5739bba | 374 | int ret; |
39279cc3 | 375 | root = btrfs_sb(sb); |
2619ba1f | 376 | |
c146afad YZ |
377 | if (sb->s_flags & MS_RDONLY) |
378 | return 0; | |
379 | ||
39279cc3 CM |
380 | sb->s_dirt = 0; |
381 | if (!wait) { | |
382 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
383 | return 0; | |
384 | } | |
771ed689 CM |
385 | |
386 | btrfs_start_delalloc_inodes(root); | |
387 | btrfs_wait_ordered_extents(root, 0); | |
388 | ||
e9d0b13b | 389 | btrfs_clean_old_snapshots(root); |
c5739bba | 390 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 391 | ret = btrfs_commit_transaction(trans, root); |
39279cc3 | 392 | sb->s_dirt = 0; |
54aa1f4d | 393 | return ret; |
2c90e5d6 CM |
394 | } |
395 | ||
39279cc3 | 396 | static void btrfs_write_super(struct super_block *sb) |
2c90e5d6 | 397 | { |
39279cc3 | 398 | sb->s_dirt = 0; |
2c90e5d6 CM |
399 | } |
400 | ||
a061fc8d | 401 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 402 | { |
a061fc8d CM |
403 | struct btrfs_fs_devices *test_fs_devices = data; |
404 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 405 | |
a061fc8d | 406 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
407 | } |
408 | ||
edf24abe CH |
409 | /* |
410 | * Find a superblock for the given device / mount point. | |
411 | * | |
412 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
413 | * for multiple device setup. Make sure to keep it in sync. | |
414 | */ | |
415 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
416 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 417 | { |
edf24abe | 418 | char *subvol_name = NULL; |
4b82d6e4 Y |
419 | struct block_device *bdev = NULL; |
420 | struct super_block *s; | |
421 | struct dentry *root; | |
8a4b83cc | 422 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 423 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
424 | int error = 0; |
425 | ||
97288f2c CH |
426 | if (!(flags & MS_RDONLY)) |
427 | mode |= FMODE_WRITE; | |
428 | ||
429 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 430 | &subvol_name, &fs_devices); |
edf24abe | 431 | if (error) |
1f483660 | 432 | return error; |
edf24abe | 433 | |
97288f2c | 434 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 435 | if (error) |
edf24abe | 436 | goto error_free_subvol_name; |
4b82d6e4 | 437 | |
97288f2c | 438 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 439 | if (error) |
edf24abe | 440 | goto error_free_subvol_name; |
8a4b83cc | 441 | |
2b82032c YZ |
442 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
443 | error = -EACCES; | |
444 | goto error_close_devices; | |
445 | } | |
446 | ||
dfe25020 | 447 | bdev = fs_devices->latest_bdev; |
a061fc8d | 448 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
449 | if (IS_ERR(s)) |
450 | goto error_s; | |
451 | ||
452 | if (s->s_root) { | |
453 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
454 | up_write(&s->s_umount); | |
455 | deactivate_super(s); | |
456 | error = -EBUSY; | |
c146afad | 457 | goto error_close_devices; |
4b82d6e4 Y |
458 | } |
459 | ||
2b82032c | 460 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
461 | } else { |
462 | char b[BDEVNAME_SIZE]; | |
463 | ||
464 | s->s_flags = flags; | |
465 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
466 | error = btrfs_fill_super(s, fs_devices, data, |
467 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 Y |
468 | if (error) { |
469 | up_write(&s->s_umount); | |
470 | deactivate_super(s); | |
1f483660 | 471 | goto error_free_subvol_name; |
4b82d6e4 Y |
472 | } |
473 | ||
788f20eb | 474 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
475 | s->s_flags |= MS_ACTIVE; |
476 | } | |
477 | ||
76fcef19 DW |
478 | if (!strcmp(subvol_name, ".")) |
479 | root = dget(s->s_root); | |
480 | else { | |
481 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
482 | root = lookup_one_len(subvol_name, s->s_root, strlen(subvol_name)); | |
483 | mutex_unlock(&s->s_root->d_inode->i_mutex); | |
484 | if (IS_ERR(root)) { | |
485 | up_write(&s->s_umount); | |
486 | deactivate_super(s); | |
487 | error = PTR_ERR(root); | |
1f483660 | 488 | goto error_free_subvol_name; |
76fcef19 DW |
489 | } |
490 | if (!root->d_inode) { | |
491 | dput(root); | |
492 | up_write(&s->s_umount); | |
493 | deactivate_super(s); | |
494 | error = -ENXIO; | |
1f483660 | 495 | goto error_free_subvol_name; |
76fcef19 | 496 | } |
4b82d6e4 Y |
497 | } |
498 | ||
499 | mnt->mnt_sb = s; | |
500 | mnt->mnt_root = root; | |
edf24abe CH |
501 | |
502 | kfree(subvol_name); | |
4b82d6e4 Y |
503 | return 0; |
504 | ||
505 | error_s: | |
506 | error = PTR_ERR(s); | |
c146afad | 507 | error_close_devices: |
8a4b83cc | 508 | btrfs_close_devices(fs_devices); |
edf24abe CH |
509 | error_free_subvol_name: |
510 | kfree(subvol_name); | |
4b82d6e4 Y |
511 | return error; |
512 | } | |
2e635a27 | 513 | |
c146afad YZ |
514 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
515 | { | |
516 | struct btrfs_root *root = btrfs_sb(sb); | |
517 | int ret; | |
518 | ||
519 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) | |
520 | return 0; | |
521 | ||
522 | if (*flags & MS_RDONLY) { | |
523 | sb->s_flags |= MS_RDONLY; | |
524 | ||
525 | ret = btrfs_commit_super(root); | |
526 | WARN_ON(ret); | |
527 | } else { | |
2b82032c YZ |
528 | if (root->fs_info->fs_devices->rw_devices == 0) |
529 | return -EACCES; | |
530 | ||
c146afad YZ |
531 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
532 | return -EINVAL; | |
533 | ||
534 | ret = btrfs_cleanup_reloc_trees(root); | |
535 | WARN_ON(ret); | |
536 | ||
537 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
538 | WARN_ON(ret); | |
539 | ||
540 | sb->s_flags &= ~MS_RDONLY; | |
541 | } | |
542 | ||
543 | return 0; | |
544 | } | |
545 | ||
8fd17795 CM |
546 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
547 | { | |
548 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 549 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 550 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 551 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
552 | |
553 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
554 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
555 | buf->f_bfree = buf->f_blocks - | |
556 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
557 | buf->f_bavail = buf->f_bfree; |
558 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
559 | buf->f_type = BTRFS_SUPER_MAGIC; | |
9d03632e DW |
560 | /* We treat it as constant endianness (it doesn't matter _which_) |
561 | because we want the fsid to come out the same whether mounted | |
562 | on a big-endian or little-endian host */ | |
563 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
564 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
565 | /* Mask in the root object ID too, to disambiguate subvols */ |
566 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
567 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
568 | ||
8fd17795 CM |
569 | return 0; |
570 | } | |
b5133862 | 571 | |
2e635a27 CM |
572 | static struct file_system_type btrfs_fs_type = { |
573 | .owner = THIS_MODULE, | |
574 | .name = "btrfs", | |
575 | .get_sb = btrfs_get_sb, | |
a061fc8d | 576 | .kill_sb = kill_anon_super, |
2e635a27 CM |
577 | .fs_flags = FS_REQUIRES_DEV, |
578 | }; | |
a9218f6b | 579 | |
d352ac68 CM |
580 | /* |
581 | * used by btrfsctl to scan devices when no FS is mounted | |
582 | */ | |
8a4b83cc CM |
583 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
584 | unsigned long arg) | |
585 | { | |
586 | struct btrfs_ioctl_vol_args *vol; | |
587 | struct btrfs_fs_devices *fs_devices; | |
f819d837 | 588 | int ret = 0; |
8a4b83cc CM |
589 | int len; |
590 | ||
e441d54d CM |
591 | if (!capable(CAP_SYS_ADMIN)) |
592 | return -EPERM; | |
593 | ||
8a4b83cc CM |
594 | vol = kmalloc(sizeof(*vol), GFP_KERNEL); |
595 | if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) { | |
596 | ret = -EFAULT; | |
597 | goto out; | |
598 | } | |
599 | len = strnlen(vol->name, BTRFS_PATH_NAME_MAX); | |
600 | switch (cmd) { | |
601 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 602 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
603 | &btrfs_fs_type, &fs_devices); |
604 | break; | |
605 | } | |
606 | out: | |
607 | kfree(vol); | |
f819d837 | 608 | return ret; |
8a4b83cc CM |
609 | } |
610 | ||
ed0dab6b Y |
611 | static void btrfs_write_super_lockfs(struct super_block *sb) |
612 | { | |
613 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
614 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
615 | mutex_lock(&root->fs_info->cleaner_mutex); | |
ed0dab6b Y |
616 | } |
617 | ||
618 | static void btrfs_unlockfs(struct super_block *sb) | |
619 | { | |
620 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
621 | mutex_unlock(&root->fs_info->cleaner_mutex); |
622 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
ed0dab6b | 623 | } |
2e635a27 | 624 | |
e20d96d6 | 625 | static struct super_operations btrfs_super_ops = { |
134e9731 | 626 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 627 | .put_super = btrfs_put_super, |
d5719762 CM |
628 | .write_super = btrfs_write_super, |
629 | .sync_fs = btrfs_sync_fs, | |
6885f308 | 630 | .show_options = generic_show_options, |
4730a4bc | 631 | .write_inode = btrfs_write_inode, |
b5133862 | 632 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
633 | .alloc_inode = btrfs_alloc_inode, |
634 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 635 | .statfs = btrfs_statfs, |
c146afad | 636 | .remount_fs = btrfs_remount, |
ed0dab6b Y |
637 | .write_super_lockfs = btrfs_write_super_lockfs, |
638 | .unlockfs = btrfs_unlockfs, | |
e20d96d6 | 639 | }; |
a9218f6b CM |
640 | |
641 | static const struct file_operations btrfs_ctl_fops = { | |
642 | .unlocked_ioctl = btrfs_control_ioctl, | |
643 | .compat_ioctl = btrfs_control_ioctl, | |
644 | .owner = THIS_MODULE, | |
645 | }; | |
646 | ||
647 | static struct miscdevice btrfs_misc = { | |
648 | .minor = MISC_DYNAMIC_MINOR, | |
649 | .name = "btrfs-control", | |
650 | .fops = &btrfs_ctl_fops | |
651 | }; | |
652 | ||
653 | static int btrfs_interface_init(void) | |
654 | { | |
655 | return misc_register(&btrfs_misc); | |
656 | } | |
657 | ||
b2950863 | 658 | static void btrfs_interface_exit(void) |
a9218f6b CM |
659 | { |
660 | if (misc_deregister(&btrfs_misc) < 0) | |
661 | printk("misc_deregister failed for control device"); | |
662 | } | |
663 | ||
2e635a27 CM |
664 | static int __init init_btrfs_fs(void) |
665 | { | |
2c90e5d6 | 666 | int err; |
58176a96 JB |
667 | |
668 | err = btrfs_init_sysfs(); | |
669 | if (err) | |
670 | return err; | |
671 | ||
39279cc3 | 672 | err = btrfs_init_cachep(); |
2c90e5d6 | 673 | if (err) |
a74a4b97 | 674 | goto free_sysfs; |
d1310b2e CM |
675 | |
676 | err = extent_io_init(); | |
2f4cbe64 WB |
677 | if (err) |
678 | goto free_cachep; | |
679 | ||
d1310b2e CM |
680 | err = extent_map_init(); |
681 | if (err) | |
682 | goto free_extent_io; | |
683 | ||
a9218f6b | 684 | err = btrfs_interface_init(); |
2f4cbe64 WB |
685 | if (err) |
686 | goto free_extent_map; | |
c8b97818 | 687 | |
a9218f6b CM |
688 | err = register_filesystem(&btrfs_fs_type); |
689 | if (err) | |
690 | goto unregister_ioctl; | |
b3c3da71 CM |
691 | |
692 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
693 | return 0; |
694 | ||
a9218f6b CM |
695 | unregister_ioctl: |
696 | btrfs_interface_exit(); | |
2f4cbe64 WB |
697 | free_extent_map: |
698 | extent_map_exit(); | |
d1310b2e CM |
699 | free_extent_io: |
700 | extent_io_exit(); | |
2f4cbe64 WB |
701 | free_cachep: |
702 | btrfs_destroy_cachep(); | |
a74a4b97 | 703 | free_sysfs: |
2f4cbe64 WB |
704 | btrfs_exit_sysfs(); |
705 | return err; | |
2e635a27 CM |
706 | } |
707 | ||
708 | static void __exit exit_btrfs_fs(void) | |
709 | { | |
39279cc3 | 710 | btrfs_destroy_cachep(); |
a52d9a80 | 711 | extent_map_exit(); |
d1310b2e | 712 | extent_io_exit(); |
a9218f6b | 713 | btrfs_interface_exit(); |
2e635a27 | 714 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 715 | btrfs_exit_sysfs(); |
8a4b83cc | 716 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 717 | btrfs_zlib_exit(); |
2e635a27 CM |
718 | } |
719 | ||
720 | module_init(init_btrfs_fs) | |
721 | module_exit(exit_btrfs_fs) | |
722 | ||
723 | MODULE_LICENSE("GPL"); |