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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 | |
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 | 70 | Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog, |
97e728d4 | 71 | Opt_ratio, Opt_flushoncommit, 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"}, |
dccae999 | 89 | {Opt_flushoncommit, "flushoncommit"}, |
97e728d4 | 90 | {Opt_ratio, "metadata_ratio=%d"}, |
33268eaf | 91 | {Opt_err, NULL}, |
95e05289 CM |
92 | }; |
93 | ||
edbd8d4e | 94 | u64 btrfs_parse_size(char *str) |
c59f8951 | 95 | { |
edbd8d4e | 96 | u64 res; |
c59f8951 CM |
97 | int mult = 1; |
98 | char *end; | |
99 | char last; | |
100 | ||
101 | res = simple_strtoul(str, &end, 10); | |
102 | ||
103 | last = end[0]; | |
104 | if (isalpha(last)) { | |
105 | last = tolower(last); | |
106 | switch (last) { | |
107 | case 'g': | |
108 | mult *= 1024; | |
109 | case 'm': | |
110 | mult *= 1024; | |
111 | case 'k': | |
112 | mult *= 1024; | |
113 | } | |
114 | res = res * mult; | |
115 | } | |
116 | return res; | |
117 | } | |
118 | ||
edf24abe CH |
119 | /* |
120 | * Regular mount options parser. Everything that is needed only when | |
121 | * reading in a new superblock is parsed here. | |
122 | */ | |
123 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 124 | { |
edf24abe | 125 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 126 | substring_t args[MAX_OPT_ARGS]; |
edf24abe | 127 | char *p, *num; |
4543df7e | 128 | int intarg; |
b6cda9bc | 129 | |
95e05289 | 130 | if (!options) |
edf24abe | 131 | return 0; |
95e05289 | 132 | |
be20aa9d CM |
133 | /* |
134 | * strsep changes the string, duplicate it because parse_options | |
135 | * gets called twice | |
136 | */ | |
137 | options = kstrdup(options, GFP_NOFS); | |
138 | if (!options) | |
139 | return -ENOMEM; | |
140 | ||
be20aa9d | 141 | |
edf24abe | 142 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
143 | int token; |
144 | if (!*p) | |
145 | continue; | |
146 | ||
147 | token = match_token(p, tokens, args); | |
148 | switch (token) { | |
dfe25020 | 149 | case Opt_degraded: |
edf24abe CH |
150 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
151 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 152 | break; |
95e05289 | 153 | case Opt_subvol: |
43e570b0 | 154 | case Opt_device: |
edf24abe | 155 | /* |
43e570b0 | 156 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
157 | * and can be happily ignored here. |
158 | */ | |
b6cda9bc CM |
159 | break; |
160 | case Opt_nodatasum: | |
edf24abe CH |
161 | printk(KERN_INFO "btrfs: setting nodatacsum\n"); |
162 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
be20aa9d CM |
163 | break; |
164 | case Opt_nodatacow: | |
edf24abe CH |
165 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
166 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
167 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 168 | break; |
c8b97818 CM |
169 | case Opt_compress: |
170 | printk(KERN_INFO "btrfs: use compression\n"); | |
171 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
172 | break; | |
e18e4809 | 173 | case Opt_ssd: |
edf24abe CH |
174 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
175 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 176 | break; |
21ad10cf | 177 | case Opt_nobarrier: |
edf24abe CH |
178 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
179 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 180 | break; |
4543df7e CM |
181 | case Opt_thread_pool: |
182 | intarg = 0; | |
183 | match_int(&args[0], &intarg); | |
184 | if (intarg) { | |
185 | info->thread_pool_size = intarg; | |
186 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
187 | info->thread_pool_size); | |
188 | } | |
189 | break; | |
c59f8951 | 190 | case Opt_max_extent: |
edf24abe CH |
191 | num = match_strdup(&args[0]); |
192 | if (num) { | |
193 | info->max_extent = btrfs_parse_size(num); | |
194 | kfree(num); | |
195 | ||
196 | info->max_extent = max_t(u64, | |
197 | info->max_extent, root->sectorsize); | |
198 | printk(KERN_INFO "btrfs: max_extent at %llu\n", | |
199 | info->max_extent); | |
c59f8951 CM |
200 | } |
201 | break; | |
6f568d35 | 202 | case Opt_max_inline: |
edf24abe CH |
203 | num = match_strdup(&args[0]); |
204 | if (num) { | |
205 | info->max_inline = btrfs_parse_size(num); | |
206 | kfree(num); | |
207 | ||
15ada040 CM |
208 | if (info->max_inline) { |
209 | info->max_inline = max_t(u64, | |
210 | info->max_inline, | |
211 | root->sectorsize); | |
212 | } | |
edf24abe CH |
213 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
214 | info->max_inline); | |
6f568d35 CM |
215 | } |
216 | break; | |
8f662a76 | 217 | case Opt_alloc_start: |
edf24abe CH |
218 | num = match_strdup(&args[0]); |
219 | if (num) { | |
220 | info->alloc_start = btrfs_parse_size(num); | |
221 | kfree(num); | |
222 | printk(KERN_INFO | |
223 | "btrfs: allocations start at %llu\n", | |
224 | info->alloc_start); | |
8f662a76 CM |
225 | } |
226 | break; | |
33268eaf JB |
227 | case Opt_noacl: |
228 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
229 | break; | |
3a5e1404 SW |
230 | case Opt_notreelog: |
231 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
232 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
233 | break; | |
dccae999 SW |
234 | case Opt_flushoncommit: |
235 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
236 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
237 | break; | |
97e728d4 JB |
238 | case Opt_ratio: |
239 | intarg = 0; | |
240 | match_int(&args[0], &intarg); | |
241 | if (intarg) { | |
242 | info->metadata_ratio = intarg; | |
243 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
244 | info->metadata_ratio); | |
245 | } | |
246 | break; | |
95e05289 | 247 | default: |
be20aa9d | 248 | break; |
95e05289 CM |
249 | } |
250 | } | |
be20aa9d | 251 | kfree(options); |
edf24abe CH |
252 | return 0; |
253 | } | |
254 | ||
255 | /* | |
256 | * Parse mount options that are required early in the mount process. | |
257 | * | |
258 | * All other options will be parsed on much later in the mount process and | |
259 | * only when we need to allocate a new super block. | |
260 | */ | |
97288f2c | 261 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
43e570b0 CH |
262 | void *holder, char **subvol_name, |
263 | struct btrfs_fs_devices **fs_devices) | |
edf24abe CH |
264 | { |
265 | substring_t args[MAX_OPT_ARGS]; | |
266 | char *opts, *p; | |
267 | int error = 0; | |
268 | ||
269 | if (!options) | |
270 | goto out; | |
271 | ||
272 | /* | |
273 | * strsep changes the string, duplicate it because parse_options | |
274 | * gets called twice | |
275 | */ | |
276 | opts = kstrdup(options, GFP_KERNEL); | |
277 | if (!opts) | |
278 | return -ENOMEM; | |
279 | ||
280 | while ((p = strsep(&opts, ",")) != NULL) { | |
281 | int token; | |
282 | if (!*p) | |
283 | continue; | |
284 | ||
285 | token = match_token(p, tokens, args); | |
286 | switch (token) { | |
287 | case Opt_subvol: | |
288 | *subvol_name = match_strdup(&args[0]); | |
289 | break; | |
43e570b0 CH |
290 | case Opt_device: |
291 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
292 | flags, holder, fs_devices); | |
293 | if (error) | |
294 | goto out_free_opts; | |
295 | break; | |
edf24abe CH |
296 | default: |
297 | break; | |
298 | } | |
299 | } | |
300 | ||
43e570b0 | 301 | out_free_opts: |
edf24abe CH |
302 | kfree(opts); |
303 | out: | |
304 | /* | |
305 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 306 | * a copy of the string "." here so that code later in the |
edf24abe CH |
307 | * mount path doesn't care if it's the default volume or another one. |
308 | */ | |
309 | if (!*subvol_name) { | |
3de4586c | 310 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
311 | if (!*subvol_name) |
312 | return -ENOMEM; | |
313 | } | |
314 | return error; | |
95e05289 CM |
315 | } |
316 | ||
d397712b | 317 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 318 | struct btrfs_fs_devices *fs_devices, |
d397712b | 319 | void *data, int silent) |
75dfe396 | 320 | { |
d397712b CM |
321 | struct inode *inode; |
322 | struct dentry *root_dentry; | |
39279cc3 CM |
323 | struct btrfs_super_block *disk_super; |
324 | struct btrfs_root *tree_root; | |
325 | struct btrfs_inode *bi; | |
326 | int err; | |
a429e513 | 327 | |
39279cc3 CM |
328 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
329 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
330 | sb->s_op = &btrfs_super_ops; | |
be6e8dc0 | 331 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 332 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 333 | sb->s_time_gran = 1; |
33268eaf | 334 | sb->s_flags |= MS_POSIXACL; |
a429e513 | 335 | |
dfe25020 | 336 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 337 | |
e58ca020 | 338 | if (IS_ERR(tree_root)) { |
39279cc3 | 339 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 340 | return PTR_ERR(tree_root); |
a429e513 | 341 | } |
39279cc3 | 342 | sb->s_fs_info = tree_root; |
5f39d397 | 343 | disk_super = &tree_root->fs_info->super_copy; |
3de4586c CM |
344 | inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID, |
345 | tree_root->fs_info->fs_root); | |
39279cc3 CM |
346 | bi = BTRFS_I(inode); |
347 | bi->location.objectid = inode->i_ino; | |
348 | bi->location.offset = 0; | |
3de4586c | 349 | bi->root = tree_root->fs_info->fs_root; |
b888db2b | 350 | |
39279cc3 | 351 | btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY); |
a429e513 | 352 | |
39279cc3 | 353 | if (!inode) { |
6567e837 | 354 | err = -ENOMEM; |
39279cc3 | 355 | goto fail_close; |
f254e52c | 356 | } |
39279cc3 CM |
357 | if (inode->i_state & I_NEW) { |
358 | btrfs_read_locked_inode(inode); | |
359 | unlock_new_inode(inode); | |
f254e52c | 360 | } |
f254e52c | 361 | |
39279cc3 CM |
362 | root_dentry = d_alloc_root(inode); |
363 | if (!root_dentry) { | |
364 | iput(inode); | |
365 | err = -ENOMEM; | |
366 | goto fail_close; | |
f254e52c | 367 | } |
e4404d6e | 368 | #if 0 |
58176a96 JB |
369 | /* this does the super kobj at the same time */ |
370 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
371 | if (err) | |
372 | goto fail_close; | |
e4404d6e | 373 | #endif |
58176a96 | 374 | |
39279cc3 | 375 | sb->s_root = root_dentry; |
6885f308 | 376 | |
6885f308 | 377 | save_mount_options(sb, data); |
2619ba1f | 378 | return 0; |
39279cc3 CM |
379 | |
380 | fail_close: | |
381 | close_ctree(tree_root); | |
382 | return err; | |
2619ba1f CM |
383 | } |
384 | ||
6bf13c0c | 385 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
386 | { |
387 | struct btrfs_trans_handle *trans; | |
dccae999 | 388 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 389 | int ret; |
2619ba1f | 390 | |
c146afad YZ |
391 | if (sb->s_flags & MS_RDONLY) |
392 | return 0; | |
393 | ||
39279cc3 CM |
394 | sb->s_dirt = 0; |
395 | if (!wait) { | |
396 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
397 | return 0; | |
398 | } | |
771ed689 CM |
399 | |
400 | btrfs_start_delalloc_inodes(root); | |
401 | btrfs_wait_ordered_extents(root, 0); | |
402 | ||
c5739bba | 403 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 404 | ret = btrfs_commit_transaction(trans, root); |
39279cc3 | 405 | sb->s_dirt = 0; |
54aa1f4d | 406 | return ret; |
2c90e5d6 CM |
407 | } |
408 | ||
a9572a15 EP |
409 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
410 | { | |
411 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
412 | struct btrfs_fs_info *info = root->fs_info; | |
413 | ||
414 | if (btrfs_test_opt(root, DEGRADED)) | |
415 | seq_puts(seq, ",degraded"); | |
416 | if (btrfs_test_opt(root, NODATASUM)) | |
417 | seq_puts(seq, ",nodatasum"); | |
418 | if (btrfs_test_opt(root, NODATACOW)) | |
419 | seq_puts(seq, ",nodatacow"); | |
420 | if (btrfs_test_opt(root, NOBARRIER)) | |
421 | seq_puts(seq, ",nobarrier"); | |
422 | if (info->max_extent != (u64)-1) | |
423 | seq_printf(seq, ",max_extent=%llu", info->max_extent); | |
424 | if (info->max_inline != 8192 * 1024) | |
425 | seq_printf(seq, ",max_inline=%llu", info->max_inline); | |
426 | if (info->alloc_start != 0) | |
427 | seq_printf(seq, ",alloc_start=%llu", info->alloc_start); | |
428 | if (info->thread_pool_size != min_t(unsigned long, | |
429 | num_online_cpus() + 2, 8)) | |
430 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
431 | if (btrfs_test_opt(root, COMPRESS)) | |
432 | seq_puts(seq, ",compress"); | |
433 | if (btrfs_test_opt(root, SSD)) | |
434 | seq_puts(seq, ",ssd"); | |
3a5e1404 | 435 | if (btrfs_test_opt(root, NOTREELOG)) |
dccae999 SW |
436 | seq_puts(seq, ",no-treelog"); |
437 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) | |
438 | seq_puts(seq, ",flush-on-commit"); | |
a9572a15 EP |
439 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
440 | seq_puts(seq, ",noacl"); | |
441 | return 0; | |
442 | } | |
443 | ||
39279cc3 | 444 | static void btrfs_write_super(struct super_block *sb) |
2c90e5d6 | 445 | { |
39279cc3 | 446 | sb->s_dirt = 0; |
2c90e5d6 CM |
447 | } |
448 | ||
a061fc8d | 449 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 450 | { |
a061fc8d CM |
451 | struct btrfs_fs_devices *test_fs_devices = data; |
452 | struct btrfs_root *root = btrfs_sb(s); | |
4b82d6e4 | 453 | |
a061fc8d | 454 | return root->fs_info->fs_devices == test_fs_devices; |
4b82d6e4 Y |
455 | } |
456 | ||
edf24abe CH |
457 | /* |
458 | * Find a superblock for the given device / mount point. | |
459 | * | |
460 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
461 | * for multiple device setup. Make sure to keep it in sync. | |
462 | */ | |
463 | static int btrfs_get_sb(struct file_system_type *fs_type, int flags, | |
464 | const char *dev_name, void *data, struct vfsmount *mnt) | |
4b82d6e4 | 465 | { |
edf24abe | 466 | char *subvol_name = NULL; |
4b82d6e4 Y |
467 | struct block_device *bdev = NULL; |
468 | struct super_block *s; | |
469 | struct dentry *root; | |
8a4b83cc | 470 | struct btrfs_fs_devices *fs_devices = NULL; |
97288f2c | 471 | fmode_t mode = FMODE_READ; |
4b82d6e4 Y |
472 | int error = 0; |
473 | ||
97288f2c CH |
474 | if (!(flags & MS_RDONLY)) |
475 | mode |= FMODE_WRITE; | |
476 | ||
477 | error = btrfs_parse_early_options(data, mode, fs_type, | |
43e570b0 | 478 | &subvol_name, &fs_devices); |
edf24abe | 479 | if (error) |
1f483660 | 480 | return error; |
edf24abe | 481 | |
97288f2c | 482 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 483 | if (error) |
edf24abe | 484 | goto error_free_subvol_name; |
4b82d6e4 | 485 | |
97288f2c | 486 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 487 | if (error) |
edf24abe | 488 | goto error_free_subvol_name; |
8a4b83cc | 489 | |
2b82032c YZ |
490 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
491 | error = -EACCES; | |
492 | goto error_close_devices; | |
493 | } | |
494 | ||
dfe25020 | 495 | bdev = fs_devices->latest_bdev; |
a061fc8d | 496 | s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices); |
4b82d6e4 Y |
497 | if (IS_ERR(s)) |
498 | goto error_s; | |
499 | ||
500 | if (s->s_root) { | |
501 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
502 | up_write(&s->s_umount); | |
503 | deactivate_super(s); | |
504 | error = -EBUSY; | |
c146afad | 505 | goto error_close_devices; |
4b82d6e4 Y |
506 | } |
507 | ||
2b82032c | 508 | btrfs_close_devices(fs_devices); |
4b82d6e4 Y |
509 | } else { |
510 | char b[BDEVNAME_SIZE]; | |
511 | ||
512 | s->s_flags = flags; | |
513 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
514 | error = btrfs_fill_super(s, fs_devices, data, |
515 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 Y |
516 | if (error) { |
517 | up_write(&s->s_umount); | |
518 | deactivate_super(s); | |
1f483660 | 519 | goto error_free_subvol_name; |
4b82d6e4 Y |
520 | } |
521 | ||
788f20eb | 522 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
523 | s->s_flags |= MS_ACTIVE; |
524 | } | |
525 | ||
76fcef19 DW |
526 | if (!strcmp(subvol_name, ".")) |
527 | root = dget(s->s_root); | |
528 | else { | |
529 | mutex_lock(&s->s_root->d_inode->i_mutex); | |
d397712b CM |
530 | root = lookup_one_len(subvol_name, s->s_root, |
531 | strlen(subvol_name)); | |
76fcef19 | 532 | mutex_unlock(&s->s_root->d_inode->i_mutex); |
d397712b | 533 | |
76fcef19 DW |
534 | if (IS_ERR(root)) { |
535 | up_write(&s->s_umount); | |
536 | deactivate_super(s); | |
537 | error = PTR_ERR(root); | |
1f483660 | 538 | goto error_free_subvol_name; |
76fcef19 DW |
539 | } |
540 | if (!root->d_inode) { | |
541 | dput(root); | |
542 | up_write(&s->s_umount); | |
543 | deactivate_super(s); | |
544 | error = -ENXIO; | |
1f483660 | 545 | goto error_free_subvol_name; |
76fcef19 | 546 | } |
4b82d6e4 Y |
547 | } |
548 | ||
549 | mnt->mnt_sb = s; | |
550 | mnt->mnt_root = root; | |
edf24abe CH |
551 | |
552 | kfree(subvol_name); | |
4b82d6e4 Y |
553 | return 0; |
554 | ||
555 | error_s: | |
556 | error = PTR_ERR(s); | |
c146afad | 557 | error_close_devices: |
8a4b83cc | 558 | btrfs_close_devices(fs_devices); |
edf24abe CH |
559 | error_free_subvol_name: |
560 | kfree(subvol_name); | |
4b82d6e4 Y |
561 | return error; |
562 | } | |
2e635a27 | 563 | |
c146afad YZ |
564 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
565 | { | |
566 | struct btrfs_root *root = btrfs_sb(sb); | |
567 | int ret; | |
568 | ||
b288052e CM |
569 | ret = btrfs_parse_options(root, data); |
570 | if (ret) | |
571 | return -EINVAL; | |
572 | ||
c146afad YZ |
573 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
574 | return 0; | |
575 | ||
576 | if (*flags & MS_RDONLY) { | |
577 | sb->s_flags |= MS_RDONLY; | |
578 | ||
579 | ret = btrfs_commit_super(root); | |
580 | WARN_ON(ret); | |
581 | } else { | |
2b82032c YZ |
582 | if (root->fs_info->fs_devices->rw_devices == 0) |
583 | return -EACCES; | |
584 | ||
c146afad YZ |
585 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
586 | return -EINVAL; | |
587 | ||
588 | ret = btrfs_cleanup_reloc_trees(root); | |
589 | WARN_ON(ret); | |
590 | ||
591 | ret = btrfs_cleanup_fs_roots(root->fs_info); | |
592 | WARN_ON(ret); | |
593 | ||
594 | sb->s_flags &= ~MS_RDONLY; | |
595 | } | |
596 | ||
597 | return 0; | |
598 | } | |
599 | ||
8fd17795 CM |
600 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
601 | { | |
602 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 603 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 604 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 605 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
8fd17795 CM |
606 | |
607 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
608 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
609 | buf->f_bfree = buf->f_blocks - | |
610 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
611 | buf->f_bavail = buf->f_bfree; |
612 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
613 | buf->f_type = BTRFS_SUPER_MAGIC; | |
d397712b | 614 | |
9d03632e | 615 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 616 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
617 | on a big-endian or little-endian host */ |
618 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
619 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
620 | /* Mask in the root object ID too, to disambiguate subvols */ |
621 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
622 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
623 | ||
8fd17795 CM |
624 | return 0; |
625 | } | |
b5133862 | 626 | |
2e635a27 CM |
627 | static struct file_system_type btrfs_fs_type = { |
628 | .owner = THIS_MODULE, | |
629 | .name = "btrfs", | |
630 | .get_sb = btrfs_get_sb, | |
a061fc8d | 631 | .kill_sb = kill_anon_super, |
2e635a27 CM |
632 | .fs_flags = FS_REQUIRES_DEV, |
633 | }; | |
a9218f6b | 634 | |
d352ac68 CM |
635 | /* |
636 | * used by btrfsctl to scan devices when no FS is mounted | |
637 | */ | |
8a4b83cc CM |
638 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
639 | unsigned long arg) | |
640 | { | |
641 | struct btrfs_ioctl_vol_args *vol; | |
642 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 643 | int ret = -ENOTTY; |
8a4b83cc | 644 | |
e441d54d CM |
645 | if (!capable(CAP_SYS_ADMIN)) |
646 | return -EPERM; | |
647 | ||
8a4b83cc | 648 | vol = kmalloc(sizeof(*vol), GFP_KERNEL); |
19d00cc1 WC |
649 | if (!vol) |
650 | return -ENOMEM; | |
651 | ||
8a4b83cc CM |
652 | if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) { |
653 | ret = -EFAULT; | |
654 | goto out; | |
655 | } | |
c071fcfd | 656 | |
8a4b83cc CM |
657 | switch (cmd) { |
658 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 659 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
660 | &btrfs_fs_type, &fs_devices); |
661 | break; | |
662 | } | |
663 | out: | |
664 | kfree(vol); | |
f819d837 | 665 | return ret; |
8a4b83cc CM |
666 | } |
667 | ||
0176260f | 668 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
669 | { |
670 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
671 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
672 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 673 | return 0; |
ed0dab6b Y |
674 | } |
675 | ||
0176260f | 676 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
677 | { |
678 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
679 | mutex_unlock(&root->fs_info->cleaner_mutex); |
680 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 681 | return 0; |
ed0dab6b | 682 | } |
2e635a27 | 683 | |
e20d96d6 | 684 | static struct super_operations btrfs_super_ops = { |
134e9731 | 685 | .delete_inode = btrfs_delete_inode, |
e20d96d6 | 686 | .put_super = btrfs_put_super, |
d5719762 CM |
687 | .write_super = btrfs_write_super, |
688 | .sync_fs = btrfs_sync_fs, | |
a9572a15 | 689 | .show_options = btrfs_show_options, |
4730a4bc | 690 | .write_inode = btrfs_write_inode, |
b5133862 | 691 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
692 | .alloc_inode = btrfs_alloc_inode, |
693 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 694 | .statfs = btrfs_statfs, |
c146afad | 695 | .remount_fs = btrfs_remount, |
0176260f LT |
696 | .freeze_fs = btrfs_freeze, |
697 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 698 | }; |
a9218f6b CM |
699 | |
700 | static const struct file_operations btrfs_ctl_fops = { | |
701 | .unlocked_ioctl = btrfs_control_ioctl, | |
702 | .compat_ioctl = btrfs_control_ioctl, | |
703 | .owner = THIS_MODULE, | |
704 | }; | |
705 | ||
706 | static struct miscdevice btrfs_misc = { | |
707 | .minor = MISC_DYNAMIC_MINOR, | |
708 | .name = "btrfs-control", | |
709 | .fops = &btrfs_ctl_fops | |
710 | }; | |
711 | ||
712 | static int btrfs_interface_init(void) | |
713 | { | |
714 | return misc_register(&btrfs_misc); | |
715 | } | |
716 | ||
b2950863 | 717 | static void btrfs_interface_exit(void) |
a9218f6b CM |
718 | { |
719 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 720 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
721 | } |
722 | ||
2e635a27 CM |
723 | static int __init init_btrfs_fs(void) |
724 | { | |
2c90e5d6 | 725 | int err; |
58176a96 JB |
726 | |
727 | err = btrfs_init_sysfs(); | |
728 | if (err) | |
729 | return err; | |
730 | ||
39279cc3 | 731 | err = btrfs_init_cachep(); |
2c90e5d6 | 732 | if (err) |
a74a4b97 | 733 | goto free_sysfs; |
d1310b2e CM |
734 | |
735 | err = extent_io_init(); | |
2f4cbe64 WB |
736 | if (err) |
737 | goto free_cachep; | |
738 | ||
d1310b2e CM |
739 | err = extent_map_init(); |
740 | if (err) | |
741 | goto free_extent_io; | |
742 | ||
a9218f6b | 743 | err = btrfs_interface_init(); |
2f4cbe64 WB |
744 | if (err) |
745 | goto free_extent_map; | |
c8b97818 | 746 | |
a9218f6b CM |
747 | err = register_filesystem(&btrfs_fs_type); |
748 | if (err) | |
749 | goto unregister_ioctl; | |
b3c3da71 CM |
750 | |
751 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
752 | return 0; |
753 | ||
a9218f6b CM |
754 | unregister_ioctl: |
755 | btrfs_interface_exit(); | |
2f4cbe64 WB |
756 | free_extent_map: |
757 | extent_map_exit(); | |
d1310b2e CM |
758 | free_extent_io: |
759 | extent_io_exit(); | |
2f4cbe64 WB |
760 | free_cachep: |
761 | btrfs_destroy_cachep(); | |
a74a4b97 | 762 | free_sysfs: |
2f4cbe64 WB |
763 | btrfs_exit_sysfs(); |
764 | return err; | |
2e635a27 CM |
765 | } |
766 | ||
767 | static void __exit exit_btrfs_fs(void) | |
768 | { | |
39279cc3 | 769 | btrfs_destroy_cachep(); |
a52d9a80 | 770 | extent_map_exit(); |
d1310b2e | 771 | extent_io_exit(); |
a9218f6b | 772 | btrfs_interface_exit(); |
2e635a27 | 773 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 774 | btrfs_exit_sysfs(); |
8a4b83cc | 775 | btrfs_cleanup_fs_uuids(); |
c8b97818 | 776 | btrfs_zlib_exit(); |
2e635a27 CM |
777 | } |
778 | ||
779 | module_init(init_btrfs_fs) | |
780 | module_exit(exit_btrfs_fs) | |
781 | ||
782 | MODULE_LICENSE("GPL"); |