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 | |
d397712b | 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 | 63 | ret = close_ctree(root); |
39279cc3 | 64 | sb->s_fs_info = NULL; |
75dfe396 CM |
65 | } |
66 | ||
95e05289 | 67 | enum { |
43e570b0 | 68 | Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow, |
dfe25020 | 69 | Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, |
c8b97818 | 70 | Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, 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 JB |
86 | {Opt_noacl, "noacl"}, |
87 | {Opt_err, NULL}, | |
95e05289 CM |
88 | }; |
89 | ||
edbd8d4e | 90 | u64 btrfs_parse_size(char *str) |
c59f8951 | 91 | { |
edbd8d4e | 92 | u64 res; |
c59f8951 CM |
93 | int mult = 1; |
94 | char *end; | |
95 | char last; | |
96 | ||
97 | res = simple_strtoul(str, &end, 10); | |
98 | ||
99 | last = end[0]; | |
100 | if (isalpha(last)) { | |
101 | last = tolower(last); | |
102 | switch (last) { | |
103 | case 'g': | |
104 | mult *= 1024; | |
105 | case 'm': | |
106 | mult *= 1024; | |
107 | case 'k': | |
108 | mult *= 1024; | |
109 | } | |
110 | res = res * mult; | |
111 | } | |
112 | return res; | |
113 | } | |
114 | ||
edf24abe CH |
115 | /* |
116 | * Regular mount options parser. Everything that is needed only when | |
117 | * reading in a new superblock is parsed here. | |
118 | */ | |
119 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 120 | { |
edf24abe | 121 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 122 | substring_t args[MAX_OPT_ARGS]; |
edf24abe | 123 | char *p, *num; |
4543df7e | 124 | int intarg; |
b6cda9bc | 125 | |
95e05289 | 126 | if (!options) |
edf24abe | 127 | return 0; |
95e05289 | 128 | |
be20aa9d CM |
129 | /* |
130 | * strsep changes the string, duplicate it because parse_options | |
131 | * gets called twice | |
132 | */ | |
133 | options = kstrdup(options, GFP_NOFS); | |
134 | if (!options) | |
135 | return -ENOMEM; | |
136 | ||
be20aa9d | 137 | |
edf24abe | 138 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
139 | int token; |
140 | if (!*p) | |
141 | continue; | |
142 | ||
143 | token = match_token(p, tokens, args); | |
144 | switch (token) { | |
dfe25020 | 145 | case Opt_degraded: |
edf24abe CH |
146 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
147 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 148 | break; |
95e05289 | 149 | case Opt_subvol: |
43e570b0 | 150 | case Opt_device: |
edf24abe | 151 | /* |
43e570b0 | 152 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
153 | * and can be happily ignored here. |
154 | */ | |
b6cda9bc CM |
155 | break; |
156 | case Opt_nodatasum: | |
edf24abe CH |
157 | printk(KERN_INFO "btrfs: setting nodatacsum\n"); |
158 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
be20aa9d CM |
159 | break; |
160 | case Opt_nodatacow: | |
edf24abe CH |
161 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
162 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
163 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 164 | break; |
c8b97818 CM |
165 | case Opt_compress: |
166 | printk(KERN_INFO "btrfs: use compression\n"); | |
167 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
168 | break; | |
e18e4809 | 169 | case Opt_ssd: |
edf24abe CH |
170 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
171 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 172 | break; |
21ad10cf | 173 | case Opt_nobarrier: |
edf24abe CH |
174 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
175 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 176 | break; |
4543df7e CM |
177 | case Opt_thread_pool: |
178 | intarg = 0; | |
179 | match_int(&args[0], &intarg); | |
180 | if (intarg) { | |
181 | info->thread_pool_size = intarg; | |
182 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
183 | info->thread_pool_size); | |
184 | } | |
185 | break; | |
c59f8951 | 186 | case Opt_max_extent: |
edf24abe CH |
187 | num = match_strdup(&args[0]); |
188 | if (num) { | |
189 | info->max_extent = btrfs_parse_size(num); | |
190 | kfree(num); | |
191 | ||
192 | info->max_extent = max_t(u64, | |
193 | info->max_extent, root->sectorsize); | |
194 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
195 | info->max_extent); | |
c59f8951 CM |
196 | } |
197 | break; | |
6f568d35 | 198 | case Opt_max_inline: |
edf24abe CH |
199 | num = match_strdup(&args[0]); |
200 | if (num) { | |
201 | info->max_inline = btrfs_parse_size(num); | |
202 | kfree(num); | |
203 | ||
15ada040 CM |
204 | if (info->max_inline) { |
205 | info->max_inline = max_t(u64, | |
206 | info->max_inline, | |
207 | root->sectorsize); | |
208 | } | |
edf24abe CH |
209 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
210 | info->max_inline); | |
6f568d35 CM |
211 | } |
212 | break; | |
8f662a76 | 213 | case Opt_alloc_start: |
edf24abe CH |
214 | num = match_strdup(&args[0]); |
215 | if (num) { | |
216 | info->alloc_start = btrfs_parse_size(num); | |
217 | kfree(num); | |
218 | printk(KERN_INFO | |
219 | "btrfs: allocations start at %llu\n", | |
220 | info->alloc_start); | |
8f662a76 CM |
221 | } |
222 | break; | |
33268eaf JB |
223 | case Opt_noacl: |
224 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
225 | break; | |
95e05289 | 226 | default: |
be20aa9d | 227 | break; |
95e05289 CM |
228 | } |
229 | } | |
be20aa9d | 230 | kfree(options); |
edf24abe CH |
231 | return 0; |
232 | } | |
233 | ||
234 | /* | |
235 | * Parse mount options that are required early in the mount process. | |
236 | * | |
237 | * All other options will be parsed on much later in the mount process and | |
238 | * only when we need to allocate a new super block. | |
239 | */ | |
97288f2c | 240 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
43e570b0 CH |
241 | void *holder, char **subvol_name, |
242 | struct btrfs_fs_devices **fs_devices) | |
edf24abe CH |
243 | { |
244 | substring_t args[MAX_OPT_ARGS]; | |
245 | char *opts, *p; | |
246 | int error = 0; | |
247 | ||
248 | if (!options) | |
249 | goto out; | |
250 | ||
251 | /* | |
252 | * strsep changes the string, duplicate it because parse_options | |
253 | * gets called twice | |
254 | */ | |
255 | opts = kstrdup(options, GFP_KERNEL); | |
256 | if (!opts) | |
257 | return -ENOMEM; | |
258 | ||
259 | while ((p = strsep(&opts, ",")) != NULL) { | |
260 | int token; | |
261 | if (!*p) | |
262 | continue; | |
263 | ||
264 | token = match_token(p, tokens, args); | |
265 | switch (token) { | |
266 | case Opt_subvol: | |
267 | *subvol_name = match_strdup(&args[0]); | |
268 | break; | |
43e570b0 CH |
269 | case Opt_device: |
270 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
271 | flags, holder, fs_devices); | |
272 | if (error) | |
273 | goto out_free_opts; | |
274 | break; | |
edf24abe CH |
275 | default: |
276 | break; | |
277 | } | |
278 | } | |
279 | ||
43e570b0 | 280 | out_free_opts: |
edf24abe CH |
281 | kfree(opts); |
282 | out: | |
283 | /* | |
284 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 285 | * a copy of the string "." here so that code later in the |
edf24abe CH |
286 | * mount path doesn't care if it's the default volume or another one. |
287 | */ | |
288 | if (!*subvol_name) { | |
3de4586c | 289 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
290 | if (!*subvol_name) |
291 | return -ENOMEM; | |
292 | } | |
293 | return error; | |
95e05289 CM |
294 | } |
295 | ||
d397712b | 296 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 297 | struct btrfs_fs_devices *fs_devices, |
d397712b | 298 | void *data, int silent) |
75dfe396 | 299 | { |
d397712b CM |
300 | struct inode *inode; |
301 | struct dentry *root_dentry; | |
39279cc3 CM |
302 | struct btrfs_super_block *disk_super; |
303 | struct btrfs_root *tree_root; | |
304 | struct btrfs_inode *bi; | |
305 | int err; | |
a429e513 | 306 | |
39279cc3 CM |
307 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
308 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
309 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 310 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 311 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 312 | sb->s_time_gran = 1; |
33268eaf | 313 | sb->s_flags |= MS_POSIXACL; |
a429e513 | 314 | |
dfe25020 | 315 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 316 | |
e58ca020 | 317 | if (IS_ERR(tree_root)) { |
39279cc3 | 318 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 319 | return PTR_ERR(tree_root); |
a429e513 | 320 | } |
39279cc3 | 321 | sb->s_fs_info = tree_root; |
5f39d397 | 322 | disk_super = &tree_root->fs_info->super_copy; |
3de4586c CM |
323 | inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID, |
324 | tree_root->fs_info->fs_root); | |
39279cc3 CM |
325 | bi = BTRFS_I(inode); |
326 | bi->location.objectid = inode->i_ino; | |
327 | bi->location.offset = 0; | |
3de4586c | 328 | bi->root = tree_root->fs_info->fs_root; |
b888db2b | 329 | |
39279cc3 | 330 | btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY); |
a429e513 | 331 | |
39279cc3 | 332 | if (!inode) { |
6567e837 | 333 | err = -ENOMEM; |
39279cc3 | 334 | goto fail_close; |
f254e52c | 335 | } |
39279cc3 CM |
336 | if (inode->i_state & I_NEW) { |
337 | btrfs_read_locked_inode(inode); | |
338 | unlock_new_inode(inode); | |
f254e52c | 339 | } |
f254e52c | 340 | |
39279cc3 CM |
341 | root_dentry = d_alloc_root(inode); |
342 | if (!root_dentry) { | |
343 | iput(inode); | |
344 | err = -ENOMEM; | |
345 | goto fail_close; | |
f254e52c | 346 | } |
e4404d6e | 347 | #if 0 |
58176a96 JB |
348 | /* this does the super kobj at the same time */ |
349 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
350 | if (err) | |
351 | goto fail_close; | |
e4404d6e | 352 | #endif |
58176a96 | 353 | |
39279cc3 | 354 | sb->s_root = root_dentry; |
6885f308 | 355 | |
6885f308 | 356 | save_mount_options(sb, data); |
2619ba1f | 357 | return 0; |
39279cc3 CM |
358 | |
359 | fail_close: | |
360 | close_ctree(tree_root); | |
361 | return err; | |
2619ba1f CM |
362 | } |
363 | ||
6bf13c0c | 364 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
365 | { |
366 | struct btrfs_trans_handle *trans; | |
39279cc3 | 367 | struct btrfs_root *root; |
c5739bba | 368 | int ret; |
39279cc3 | 369 | root = btrfs_sb(sb); |
2619ba1f | 370 | |
c146afad YZ |
371 | if (sb->s_flags & MS_RDONLY) |
372 | return 0; | |
373 | ||
39279cc3 CM |
374 | sb->s_dirt = 0; |
375 | if (!wait) { | |
376 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
377 | return 0; | |
378 | } | |
771ed689 CM |
379 | |
380 | btrfs_start_delalloc_inodes(root); | |
381 | btrfs_wait_ordered_extents(root, 0); | |
382 | ||
e9d0b13b | 383 | btrfs_clean_old_snapshots(root); |
c5739bba | 384 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 385 | ret = btrfs_commit_transaction(trans, root); |
39279cc3 | 386 | sb->s_dirt = 0; |
54aa1f4d | 387 | return ret; |
2c90e5d6 CM |
388 | } |
389 | ||
39279cc3 | 390 | static void btrfs_write_super(struct super_block *sb) |
2c90e5d6 | 391 | { |
39279cc3 | 392 | sb->s_dirt = 0; |
2c90e5d6 CM |
393 | } |
394 | ||
a061fc8d | 395 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 396 | { |
a061fc8d CM |
397 | struct btrfs_fs_devices *test_fs_devices = data; |
398 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 399 | |
a061fc8d | 400 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
401 | } |
402 | ||
edf24abe CH |
403 | /* |
404 | * Find a superblock for the given device / mount point. | |
405 | * | |
406 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
407 | * for multiple device setup. Make sure to keep it in sync. | |
408 | */ | |
409 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
410 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 411 | { |
edf24abe | 412 | char *subvol_name = NULL; |
4b82d6e4 Y |
413 | struct block_device *bdev = NULL; |
414 | struct super_block *s; | |
415 | struct dentry *root; | |
8a4b83cc | 416 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 417 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
418 | int error = 0; |
419 | ||
97288f2c CH |
420 | if (!(flags & MS_RDONLY)) |
421 | mode |= FMODE_WRITE; | |
422 | ||
423 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 424 | &subvol_name, &fs_devices); |
edf24abe | 425 | if (error) |
1f483660 | 426 | return error; |
edf24abe | 427 | |
97288f2c | 428 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 429 | if (error) |
edf24abe | 430 | goto error_free_subvol_name; |
4b82d6e4 | 431 | |
97288f2c | 432 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 433 | if (error) |
edf24abe | 434 | goto error_free_subvol_name; |
8a4b83cc | 435 | |
2b82032c YZ |
436 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
437 | error = -EACCES; | |
438 | goto error_close_devices; | |
439 | } | |
440 | ||
dfe25020 | 441 | bdev = fs_devices->latest_bdev; |
a061fc8d | 442 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
443 | if (IS_ERR(s)) |
444 | goto error_s; | |
445 | ||
446 | if (s->s_root) { | |
447 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
448 | up_write(&s->s_umount); | |
449 | deactivate_super(s); | |
450 | error = -EBUSY; | |
c146afad | 451 | goto error_close_devices; |
4b82d6e4 Y |
452 | } |
453 | ||
2b82032c | 454 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
455 | } else { |
456 | char b[BDEVNAME_SIZE]; | |
457 | ||
458 | s->s_flags = flags; | |
459 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
460 | error = btrfs_fill_super(s, fs_devices, data, |
461 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 Y |
462 | if (error) { |
463 | up_write(&s->s_umount); | |
464 | deactivate_super(s); | |
1f483660 | 465 | goto error_free_subvol_name; |
4b82d6e4 Y |
466 | } |
467 | ||
788f20eb | 468 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
469 | s->s_flags |= MS_ACTIVE; |
470 | } | |
471 | ||
76fcef19 DW |
472 | if (!strcmp(subvol_name, ".")) |
473 | root = dget(s->s_root); | |
474 | else { | |
475 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
d397712b CM |
476 | root = lookup_one_len(subvol_name, s->s_root, |
477 | strlen(subvol_name)); | |
76fcef19 | 478 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
d397712b | 479 | |
76fcef19 DW |
480 | if (IS_ERR(root)) { |
481 | up_write(&s->s_umount); | |
482 | deactivate_super(s); | |
483 | error = PTR_ERR(root); | |
1f483660 | 484 | goto error_free_subvol_name; |
76fcef19 DW |
485 | } |
486 | if (!root->d_inode) { | |
487 | dput(root); | |
488 | up_write(&s->s_umount); | |
489 | deactivate_super(s); | |
490 | error = -ENXIO; | |
1f483660 | 491 | goto error_free_subvol_name; |
76fcef19 | 492 | } |
4b82d6e4 Y |
493 | } |
494 | ||
495 | mnt->mnt_sb = s; | |
496 | mnt->mnt_root = root; | |
edf24abe CH |
497 | |
498 | kfree(subvol_name); | |
4b82d6e4 Y |
499 | return 0; |
500 | ||
501 | error_s: | |
502 | error = PTR_ERR(s); | |
c146afad | 503 | error_close_devices: |
8a4b83cc | 504 | btrfs_close_devices(fs_devices); |
edf24abe CH |
505 | error_free_subvol_name: |
506 | kfree(subvol_name); | |
4b82d6e4 Y |
507 | return error; |
508 | } | |
2e635a27 | 509 | |
c146afad YZ |
510 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
511 | { | |
512 | struct btrfs_root *root = btrfs_sb(sb); | |
513 | int ret; | |
514 | ||
515 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) | |
516 | return 0; | |
517 | ||
518 | if (*flags & MS_RDONLY) { | |
519 | sb->s_flags |= MS_RDONLY; | |
520 | ||
521 | ret = btrfs_commit_super(root); | |
522 | WARN_ON(ret); | |
523 | } else { | |
2b82032c YZ |
524 | if (root->fs_info->fs_devices->rw_devices == 0) |
525 | return -EACCES; | |
526 | ||
c146afad YZ |
527 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
528 | return -EINVAL; | |
529 | ||
530 | ret = btrfs_cleanup_reloc_trees(root); | |
531 | WARN_ON(ret); | |
532 | ||
533 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
534 | WARN_ON(ret); | |
535 | ||
536 | sb->s_flags &= ~MS_RDONLY; | |
537 | } | |
538 | ||
539 | return 0; | |
540 | } | |
541 | ||
8fd17795 CM |
542 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
543 | { | |
544 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 545 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 546 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 547 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
548 | |
549 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
550 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
551 | buf->f_bfree = buf->f_blocks - | |
552 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
553 | buf->f_bavail = buf->f_bfree; |
554 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
555 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 556 | |
9d03632e | 557 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 558 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
559 | on a big-endian or little-endian host */ |
560 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
561 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
562 | /* Mask in the root object ID too, to disambiguate subvols */ |
563 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
564 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
565 | ||
8fd17795 CM |
566 | return 0; |
567 | } | |
b5133862 | 568 | |
2e635a27 CM |
569 | static struct file_system_type btrfs_fs_type = { |
570 | .owner = THIS_MODULE, | |
571 | .name = "btrfs", | |
572 | .get_sb = btrfs_get_sb, | |
a061fc8d | 573 | .kill_sb = kill_anon_super, |
2e635a27 CM |
574 | .fs_flags = FS_REQUIRES_DEV, |
575 | }; | |
a9218f6b | 576 | |
d352ac68 CM |
577 | /* |
578 | * used by btrfsctl to scan devices when no FS is mounted | |
579 | */ | |
8a4b83cc CM |
580 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
581 | unsigned long arg) | |
582 | { | |
583 | struct btrfs_ioctl_vol_args *vol; | |
584 | struct btrfs_fs_devices *fs_devices; | |
f819d837 | 585 | int ret = 0; |
8a4b83cc CM |
586 | int len; |
587 | ||
e441d54d CM |
588 | if (!capable(CAP_SYS_ADMIN)) |
589 | return -EPERM; | |
590 | ||
8a4b83cc CM |
591 | vol = kmalloc(sizeof(*vol), GFP_KERNEL); |
592 | if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) { | |
593 | ret = -EFAULT; | |
594 | goto out; | |
595 | } | |
596 | len = strnlen(vol->name, BTRFS_PATH_NAME_MAX); | |
597 | switch (cmd) { | |
598 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 599 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
600 | &btrfs_fs_type, &fs_devices); |
601 | break; | |
602 | } | |
603 | out: | |
604 | kfree(vol); | |
f819d837 | 605 | return ret; |
8a4b83cc CM |
606 | } |
607 | ||
ed0dab6b Y |
608 | static void btrfs_write_super_lockfs(struct super_block *sb) |
609 | { | |
610 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
611 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
612 | mutex_lock(&root->fs_info->cleaner_mutex); | |
ed0dab6b Y |
613 | } |
614 | ||
615 | static void btrfs_unlockfs(struct super_block *sb) | |
616 | { | |
617 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
618 | mutex_unlock(&root->fs_info->cleaner_mutex); |
619 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
ed0dab6b | 620 | } |
2e635a27 | 621 | |
e20d96d6 | 622 | static struct super_operations btrfs_super_ops = { |
134e9731 | 623 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 624 | .put_super = btrfs_put_super, |
d5719762 CM |
625 | .write_super = btrfs_write_super, |
626 | .sync_fs = btrfs_sync_fs, | |
6885f308 | 627 | .show_options = generic_show_options, |
4730a4bc | 628 | .write_inode = btrfs_write_inode, |
b5133862 | 629 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
630 | .alloc_inode = btrfs_alloc_inode, |
631 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 632 | .statfs = btrfs_statfs, |
c146afad | 633 | .remount_fs = btrfs_remount, |
ed0dab6b Y |
634 | .write_super_lockfs = btrfs_write_super_lockfs, |
635 | .unlockfs = btrfs_unlockfs, | |
e20d96d6 | 636 | }; |
a9218f6b CM |
637 | |
638 | static const struct file_operations btrfs_ctl_fops = { | |
639 | .unlocked_ioctl = btrfs_control_ioctl, | |
640 | .compat_ioctl = btrfs_control_ioctl, | |
641 | .owner = THIS_MODULE, | |
642 | }; | |
643 | ||
644 | static struct miscdevice btrfs_misc = { | |
645 | .minor = MISC_DYNAMIC_MINOR, | |
646 | .name = "btrfs-control", | |
647 | .fops = &btrfs_ctl_fops | |
648 | }; | |
649 | ||
650 | static int btrfs_interface_init(void) | |
651 | { | |
652 | return misc_register(&btrfs_misc); | |
653 | } | |
654 | ||
b2950863 | 655 | static void btrfs_interface_exit(void) |
a9218f6b CM |
656 | { |
657 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 658 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
659 | } |
660 | ||
2e635a27 CM |
661 | static int __init init_btrfs_fs(void) |
662 | { | |
2c90e5d6 | 663 | int err; |
58176a96 JB |
664 | |
665 | err = btrfs_init_sysfs(); | |
666 | if (err) | |
667 | return err; | |
668 | ||
39279cc3 | 669 | err = btrfs_init_cachep(); |
2c90e5d6 | 670 | if (err) |
a74a4b97 | 671 | goto free_sysfs; |
d1310b2e CM |
672 | |
673 | err = extent_io_init(); | |
2f4cbe64 WB |
674 | if (err) |
675 | goto free_cachep; | |
676 | ||
d1310b2e CM |
677 | err = extent_map_init(); |
678 | if (err) | |
679 | goto free_extent_io; | |
680 | ||
a9218f6b | 681 | err = btrfs_interface_init(); |
2f4cbe64 WB |
682 | if (err) |
683 | goto free_extent_map; | |
c8b97818 | 684 | |
a9218f6b CM |
685 | err = register_filesystem(&btrfs_fs_type); |
686 | if (err) | |
687 | goto unregister_ioctl; | |
b3c3da71 CM |
688 | |
689 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
690 | return 0; |
691 | ||
a9218f6b CM |
692 | unregister_ioctl: |
693 | btrfs_interface_exit(); | |
2f4cbe64 WB |
694 | free_extent_map: |
695 | extent_map_exit(); | |
d1310b2e CM |
696 | free_extent_io: |
697 | extent_io_exit(); | |
2f4cbe64 WB |
698 | free_cachep: |
699 | btrfs_destroy_cachep(); | |
a74a4b97 | 700 | free_sysfs: |
2f4cbe64 WB |
701 | btrfs_exit_sysfs(); |
702 | return err; | |
2e635a27 CM |
703 | } |
704 | ||
705 | static void __exit exit_btrfs_fs(void) | |
706 | { | |
39279cc3 | 707 | btrfs_destroy_cachep(); |
a52d9a80 | 708 | extent_map_exit(); |
d1310b2e | 709 | extent_io_exit(); |
a9218f6b | 710 | btrfs_interface_exit(); |
2e635a27 | 711 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 712 | btrfs_exit_sysfs(); |
8a4b83cc | 713 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 714 | btrfs_zlib_exit(); |
2e635a27 CM |
715 | } |
716 | ||
717 | module_init(init_btrfs_fs) | |
718 | module_exit(exit_btrfs_fs) | |
719 | ||
720 | MODULE_LICENSE("GPL"); |