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 | |
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, |
3a5e1404 SW |
70 | Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog, |
71 | Opt_err, | |
95e05289 CM |
72 | }; |
73 | ||
74 | static match_table_t tokens = { | |
dfe25020 | 75 | {Opt_degraded, "degraded"}, |
95e05289 | 76 | {Opt_subvol, "subvol=%s"}, |
43e570b0 | 77 | {Opt_device, "device=%s"}, |
b6cda9bc | 78 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 79 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 80 | {Opt_nobarrier, "nobarrier"}, |
c59f8951 | 81 | {Opt_max_extent, "max_extent=%s"}, |
6f568d35 | 82 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 83 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 84 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 85 | {Opt_compress, "compress"}, |
e18e4809 | 86 | {Opt_ssd, "ssd"}, |
33268eaf | 87 | {Opt_noacl, "noacl"}, |
3a5e1404 | 88 | {Opt_notreelog, "notreelog"}, |
33268eaf | 89 | {Opt_err, NULL}, |
95e05289 CM |
90 | }; |
91 | ||
edbd8d4e | 92 | u64 btrfs_parse_size(char *str) |
c59f8951 | 93 | { |
edbd8d4e | 94 | u64 res; |
c59f8951 CM |
95 | int mult = 1; |
96 | char *end; | |
97 | char last; | |
98 | ||
99 | res = simple_strtoul(str, &end, 10); | |
100 | ||
101 | last = end[0]; | |
102 | if (isalpha(last)) { | |
103 | last = tolower(last); | |
104 | switch (last) { | |
105 | case 'g': | |
106 | mult *= 1024; | |
107 | case 'm': | |
108 | mult *= 1024; | |
109 | case 'k': | |
110 | mult *= 1024; | |
111 | } | |
112 | res = res * mult; | |
113 | } | |
114 | return res; | |
115 | } | |
116 | ||
edf24abe CH |
117 | /* |
118 | * Regular mount options parser. Everything that is needed only when | |
119 | * reading in a new superblock is parsed here. | |
120 | */ | |
121 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 122 | { |
edf24abe | 123 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 124 | substring_t args[MAX_OPT_ARGS]; |
edf24abe | 125 | char *p, *num; |
4543df7e | 126 | int intarg; |
b6cda9bc | 127 | |
95e05289 | 128 | if (!options) |
edf24abe | 129 | return 0; |
95e05289 | 130 | |
be20aa9d CM |
131 | /* |
132 | * strsep changes the string, duplicate it because parse_options | |
133 | * gets called twice | |
134 | */ | |
135 | options = kstrdup(options, GFP_NOFS); | |
136 | if (!options) | |
137 | return -ENOMEM; | |
138 | ||
be20aa9d | 139 | |
edf24abe | 140 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
141 | int token; |
142 | if (!*p) | |
143 | continue; | |
144 | ||
145 | token = match_token(p, tokens, args); | |
146 | switch (token) { | |
dfe25020 | 147 | case Opt_degraded: |
edf24abe CH |
148 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
149 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 150 | break; |
95e05289 | 151 | case Opt_subvol: |
43e570b0 | 152 | case Opt_device: |
edf24abe | 153 | /* |
43e570b0 | 154 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
155 | * and can be happily ignored here. |
156 | */ | |
b6cda9bc CM |
157 | break; |
158 | case Opt_nodatasum: | |
edf24abe CH |
159 | printk(KERN_INFO "btrfs: setting nodatacsum\n"); |
160 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
be20aa9d CM |
161 | break; |
162 | case Opt_nodatacow: | |
edf24abe CH |
163 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
164 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
165 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 166 | break; |
c8b97818 CM |
167 | case Opt_compress: |
168 | printk(KERN_INFO "btrfs: use compression\n"); | |
169 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
170 | break; | |
e18e4809 | 171 | case Opt_ssd: |
edf24abe CH |
172 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
173 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 174 | break; |
21ad10cf | 175 | case Opt_nobarrier: |
edf24abe CH |
176 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
177 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 178 | break; |
4543df7e CM |
179 | case Opt_thread_pool: |
180 | intarg = 0; | |
181 | match_int(&args[0], &intarg); | |
182 | if (intarg) { | |
183 | info->thread_pool_size = intarg; | |
184 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
185 | info->thread_pool_size); | |
186 | } | |
187 | break; | |
c59f8951 | 188 | case Opt_max_extent: |
edf24abe CH |
189 | num = match_strdup(&args[0]); |
190 | if (num) { | |
191 | info->max_extent = btrfs_parse_size(num); | |
192 | kfree(num); | |
193 | ||
194 | info->max_extent = max_t(u64, | |
195 | info->max_extent, root->sectorsize); | |
196 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
197 | info->max_extent); | |
c59f8951 CM |
198 | } |
199 | break; | |
6f568d35 | 200 | case Opt_max_inline: |
edf24abe CH |
201 | num = match_strdup(&args[0]); |
202 | if (num) { | |
203 | info->max_inline = btrfs_parse_size(num); | |
204 | kfree(num); | |
205 | ||
15ada040 CM |
206 | if (info->max_inline) { |
207 | info->max_inline = max_t(u64, | |
208 | info->max_inline, | |
209 | root->sectorsize); | |
210 | } | |
edf24abe CH |
211 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
212 | info->max_inline); | |
6f568d35 CM |
213 | } |
214 | break; | |
8f662a76 | 215 | case Opt_alloc_start: |
edf24abe CH |
216 | num = match_strdup(&args[0]); |
217 | if (num) { | |
218 | info->alloc_start = btrfs_parse_size(num); | |
219 | kfree(num); | |
220 | printk(KERN_INFO | |
221 | "btrfs: allocations start at %llu\n", | |
222 | info->alloc_start); | |
8f662a76 CM |
223 | } |
224 | break; | |
33268eaf JB |
225 | case Opt_noacl: |
226 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
227 | break; | |
3a5e1404 SW |
228 | case Opt_notreelog: |
229 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
230 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
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 | ||
d397712b | 302 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 303 | struct btrfs_fs_devices *fs_devices, |
d397712b | 304 | void *data, int silent) |
75dfe396 | 305 | { |
d397712b CM |
306 | struct inode *inode; |
307 | struct dentry *root_dentry; | |
39279cc3 CM |
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 | ||
c5739bba | 389 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 390 | ret = btrfs_commit_transaction(trans, root); |
39279cc3 | 391 | sb->s_dirt = 0; |
54aa1f4d | 392 | return ret; |
2c90e5d6 CM |
393 | } |
394 | ||
a9572a15 EP |
395 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
396 | { | |
397 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
398 | struct btrfs_fs_info *info = root->fs_info; | |
399 | ||
400 | if (btrfs_test_opt(root, DEGRADED)) | |
401 | seq_puts(seq, ",degraded"); | |
402 | if (btrfs_test_opt(root, NODATASUM)) | |
403 | seq_puts(seq, ",nodatasum"); | |
404 | if (btrfs_test_opt(root, NODATACOW)) | |
405 | seq_puts(seq, ",nodatacow"); | |
406 | if (btrfs_test_opt(root, NOBARRIER)) | |
407 | seq_puts(seq, ",nobarrier"); | |
408 | if (info->max_extent != (u64)-1) | |
409 | seq_printf(seq, ",max_extent=%llu", info->max_extent); | |
410 | if (info->max_inline != 8192 * 1024) | |
411 | seq_printf(seq, ",max_inline=%llu", info->max_inline); | |
412 | if (info->alloc_start != 0) | |
413 | seq_printf(seq, ",alloc_start=%llu", info->alloc_start); | |
414 | if (info->thread_pool_size != min_t(unsigned long, | |
415 | num_online_cpus() + 2, 8)) | |
416 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
417 | if (btrfs_test_opt(root, COMPRESS)) | |
418 | seq_puts(seq, ",compress"); | |
419 | if (btrfs_test_opt(root, SSD)) | |
420 | seq_puts(seq, ",ssd"); | |
3a5e1404 SW |
421 | if (btrfs_test_opt(root, NOTREELOG)) |
422 | seq_puts(seq, ",notreelog"); | |
a9572a15 EP |
423 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
424 | seq_puts(seq, ",noacl"); | |
425 | return 0; | |
426 | } | |
427 | ||
39279cc3 | 428 | static void btrfs_write_super(struct super_block *sb) |
2c90e5d6 | 429 | { |
39279cc3 | 430 | sb->s_dirt = 0; |
2c90e5d6 CM |
431 | } |
432 | ||
a061fc8d | 433 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 434 | { |
a061fc8d CM |
435 | struct btrfs_fs_devices *test_fs_devices = data; |
436 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 437 | |
a061fc8d | 438 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
439 | } |
440 | ||
edf24abe CH |
441 | /* |
442 | * Find a superblock for the given device / mount point. | |
443 | * | |
444 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
445 | * for multiple device setup. Make sure to keep it in sync. | |
446 | */ | |
447 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
448 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 449 | { |
edf24abe | 450 | char *subvol_name = NULL; |
4b82d6e4 Y |
451 | struct block_device *bdev = NULL; |
452 | struct super_block *s; | |
453 | struct dentry *root; | |
8a4b83cc | 454 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 455 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
456 | int error = 0; |
457 | ||
97288f2c CH |
458 | if (!(flags & MS_RDONLY)) |
459 | mode |= FMODE_WRITE; | |
460 | ||
461 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 462 | &subvol_name, &fs_devices); |
edf24abe | 463 | if (error) |
1f483660 | 464 | return error; |
edf24abe | 465 | |
97288f2c | 466 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 467 | if (error) |
edf24abe | 468 | goto error_free_subvol_name; |
4b82d6e4 | 469 | |
97288f2c | 470 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 471 | if (error) |
edf24abe | 472 | goto error_free_subvol_name; |
8a4b83cc | 473 | |
2b82032c YZ |
474 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
475 | error = -EACCES; | |
476 | goto error_close_devices; | |
477 | } | |
478 | ||
dfe25020 | 479 | bdev = fs_devices->latest_bdev; |
a061fc8d | 480 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
481 | if (IS_ERR(s)) |
482 | goto error_s; | |
483 | ||
484 | if (s->s_root) { | |
485 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
486 | up_write(&s->s_umount); | |
487 | deactivate_super(s); | |
488 | error = -EBUSY; | |
c146afad | 489 | goto error_close_devices; |
4b82d6e4 Y |
490 | } |
491 | ||
2b82032c | 492 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
493 | } else { |
494 | char b[BDEVNAME_SIZE]; | |
495 | ||
496 | s->s_flags = flags; | |
497 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
498 | error = btrfs_fill_super(s, fs_devices, data, |
499 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 Y |
500 | if (error) { |
501 | up_write(&s->s_umount); | |
502 | deactivate_super(s); | |
1f483660 | 503 | goto error_free_subvol_name; |
4b82d6e4 Y |
504 | } |
505 | ||
788f20eb | 506 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
507 | s->s_flags |= MS_ACTIVE; |
508 | } | |
509 | ||
76fcef19 DW |
510 | if (!strcmp(subvol_name, ".")) |
511 | root = dget(s->s_root); | |
512 | else { | |
513 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
d397712b CM |
514 | root = lookup_one_len(subvol_name, s->s_root, |
515 | strlen(subvol_name)); | |
76fcef19 | 516 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
d397712b | 517 | |
76fcef19 DW |
518 | if (IS_ERR(root)) { |
519 | up_write(&s->s_umount); | |
520 | deactivate_super(s); | |
521 | error = PTR_ERR(root); | |
1f483660 | 522 | goto error_free_subvol_name; |
76fcef19 DW |
523 | } |
524 | if (!root->d_inode) { | |
525 | dput(root); | |
526 | up_write(&s->s_umount); | |
527 | deactivate_super(s); | |
528 | error = -ENXIO; | |
1f483660 | 529 | goto error_free_subvol_name; |
76fcef19 | 530 | } |
4b82d6e4 Y |
531 | } |
532 | ||
533 | mnt->mnt_sb = s; | |
534 | mnt->mnt_root = root; | |
edf24abe CH |
535 | |
536 | kfree(subvol_name); | |
4b82d6e4 Y |
537 | return 0; |
538 | ||
539 | error_s: | |
540 | error = PTR_ERR(s); | |
c146afad | 541 | error_close_devices: |
8a4b83cc | 542 | btrfs_close_devices(fs_devices); |
edf24abe CH |
543 | error_free_subvol_name: |
544 | kfree(subvol_name); | |
4b82d6e4 Y |
545 | return error; |
546 | } | |
2e635a27 | 547 | |
c146afad YZ |
548 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
549 | { | |
550 | struct btrfs_root *root = btrfs_sb(sb); | |
551 | int ret; | |
552 | ||
b288052e CM |
553 | ret = btrfs_parse_options(root, data); |
554 | if (ret) | |
555 | return -EINVAL; | |
556 | ||
c146afad YZ |
557 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
558 | return 0; | |
559 | ||
560 | if (*flags & MS_RDONLY) { | |
561 | sb->s_flags |= MS_RDONLY; | |
562 | ||
563 | ret = btrfs_commit_super(root); | |
564 | WARN_ON(ret); | |
565 | } else { | |
2b82032c YZ |
566 | if (root->fs_info->fs_devices->rw_devices == 0) |
567 | return -EACCES; | |
568 | ||
c146afad YZ |
569 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
570 | return -EINVAL; | |
571 | ||
572 | ret = btrfs_cleanup_reloc_trees(root); | |
573 | WARN_ON(ret); | |
574 | ||
575 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
576 | WARN_ON(ret); | |
577 | ||
578 | sb->s_flags &= ~MS_RDONLY; | |
579 | } | |
580 | ||
581 | return 0; | |
582 | } | |
583 | ||
8fd17795 CM |
584 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
585 | { | |
586 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 587 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 588 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 589 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
590 | |
591 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
592 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
593 | buf->f_bfree = buf->f_blocks - | |
594 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
595 | buf->f_bavail = buf->f_bfree; |
596 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
597 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 598 | |
9d03632e | 599 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 600 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
601 | on a big-endian or little-endian host */ |
602 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
603 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
604 | /* Mask in the root object ID too, to disambiguate subvols */ |
605 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
606 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
607 | ||
8fd17795 CM |
608 | return 0; |
609 | } | |
b5133862 | 610 | |
2e635a27 CM |
611 | static struct file_system_type btrfs_fs_type = { |
612 | .owner = THIS_MODULE, | |
613 | .name = "btrfs", | |
614 | .get_sb = btrfs_get_sb, | |
a061fc8d | 615 | .kill_sb = kill_anon_super, |
2e635a27 CM |
616 | .fs_flags = FS_REQUIRES_DEV, |
617 | }; | |
a9218f6b | 618 | |
d352ac68 CM |
619 | /* |
620 | * used by btrfsctl to scan devices when no FS is mounted | |
621 | */ | |
8a4b83cc CM |
622 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
623 | unsigned long arg) | |
624 | { | |
625 | struct btrfs_ioctl_vol_args *vol; | |
626 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 627 | int ret = -ENOTTY; |
8a4b83cc | 628 | |
e441d54d CM |
629 | if (!capable(CAP_SYS_ADMIN)) |
630 | return -EPERM; | |
631 | ||
8a4b83cc | 632 | vol = kmalloc(sizeof(*vol), GFP_KERNEL); |
19d00cc1 WC |
633 | if (!vol) |
634 | return -ENOMEM; | |
635 | ||
8a4b83cc CM |
636 | if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) { |
637 | ret = -EFAULT; | |
638 | goto out; | |
639 | } | |
c071fcfd | 640 | |
8a4b83cc CM |
641 | switch (cmd) { |
642 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 643 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
644 | &btrfs_fs_type, &fs_devices); |
645 | break; | |
646 | } | |
647 | out: | |
648 | kfree(vol); | |
f819d837 | 649 | return ret; |
8a4b83cc CM |
650 | } |
651 | ||
0176260f | 652 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
653 | { |
654 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
655 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
656 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 657 | return 0; |
ed0dab6b Y |
658 | } |
659 | ||
0176260f | 660 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
661 | { |
662 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
663 | mutex_unlock(&root->fs_info->cleaner_mutex); |
664 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 665 | return 0; |
ed0dab6b | 666 | } |
2e635a27 | 667 | |
e20d96d6 | 668 | static struct super_operations btrfs_super_ops = { |
134e9731 | 669 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 670 | .put_super = btrfs_put_super, |
d5719762 CM |
671 | .write_super = btrfs_write_super, |
672 | .sync_fs = btrfs_sync_fs, | |
a9572a15 | 673 | .show_options = btrfs_show_options, |
4730a4bc | 674 | .write_inode = btrfs_write_inode, |
b5133862 | 675 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
676 | .alloc_inode = btrfs_alloc_inode, |
677 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 678 | .statfs = btrfs_statfs, |
c146afad | 679 | .remount_fs = btrfs_remount, |
0176260f LT |
680 | .freeze_fs = btrfs_freeze, |
681 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 682 | }; |
a9218f6b CM |
683 | |
684 | static const struct file_operations btrfs_ctl_fops = { | |
685 | .unlocked_ioctl = btrfs_control_ioctl, | |
686 | .compat_ioctl = btrfs_control_ioctl, | |
687 | .owner = THIS_MODULE, | |
688 | }; | |
689 | ||
690 | static struct miscdevice btrfs_misc = { | |
691 | .minor = MISC_DYNAMIC_MINOR, | |
692 | .name = "btrfs-control", | |
693 | .fops = &btrfs_ctl_fops | |
694 | }; | |
695 | ||
696 | static int btrfs_interface_init(void) | |
697 | { | |
698 | return misc_register(&btrfs_misc); | |
699 | } | |
700 | ||
b2950863 | 701 | static void btrfs_interface_exit(void) |
a9218f6b CM |
702 | { |
703 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 704 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
705 | } |
706 | ||
2e635a27 CM |
707 | static int __init init_btrfs_fs(void) |
708 | { | |
2c90e5d6 | 709 | int err; |
58176a96 JB |
710 | |
711 | err = btrfs_init_sysfs(); | |
712 | if (err) | |
713 | return err; | |
714 | ||
39279cc3 | 715 | err = btrfs_init_cachep(); |
2c90e5d6 | 716 | if (err) |
a74a4b97 | 717 | goto free_sysfs; |
d1310b2e CM |
718 | |
719 | err = extent_io_init(); | |
2f4cbe64 WB |
720 | if (err) |
721 | goto free_cachep; | |
722 | ||
d1310b2e CM |
723 | err = extent_map_init(); |
724 | if (err) | |
725 | goto free_extent_io; | |
726 | ||
a9218f6b | 727 | err = btrfs_interface_init(); |
2f4cbe64 WB |
728 | if (err) |
729 | goto free_extent_map; | |
c8b97818 | 730 | |
a9218f6b CM |
731 | err = register_filesystem(&btrfs_fs_type); |
732 | if (err) | |
733 | goto unregister_ioctl; | |
b3c3da71 CM |
734 | |
735 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
736 | return 0; |
737 | ||
a9218f6b CM |
738 | unregister_ioctl: |
739 | btrfs_interface_exit(); | |
2f4cbe64 WB |
740 | free_extent_map: |
741 | extent_map_exit(); | |
d1310b2e CM |
742 | free_extent_io: |
743 | extent_io_exit(); | |
2f4cbe64 WB |
744 | free_cachep: |
745 | btrfs_destroy_cachep(); | |
a74a4b97 | 746 | free_sysfs: |
2f4cbe64 WB |
747 | btrfs_exit_sysfs(); |
748 | return err; | |
2e635a27 CM |
749 | } |
750 | ||
751 | static void __exit exit_btrfs_fs(void) | |
752 | { | |
39279cc3 | 753 | btrfs_destroy_cachep(); |
a52d9a80 | 754 | extent_map_exit(); |
d1310b2e | 755 | extent_io_exit(); |
a9218f6b | 756 | btrfs_interface_exit(); |
2e635a27 | 757 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 758 | btrfs_exit_sysfs(); |
8a4b83cc | 759 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 760 | btrfs_zlib_exit(); |
2e635a27 CM |
761 | } |
762 | ||
763 | module_init(init_btrfs_fs) | |
764 | module_exit(exit_btrfs_fs) | |
765 | ||
766 | MODULE_LICENSE("GPL"); |