Commit | Line | Data |
---|---|---|
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> |
2e635a27 | 39 | #include "ctree.h" |
e20d96d6 | 40 | #include "disk-io.h" |
d5719762 | 41 | #include "transaction.h" |
2c90e5d6 | 42 | #include "btrfs_inode.h" |
c5739bba | 43 | #include "ioctl.h" |
3a686375 | 44 | #include "print-tree.h" |
5103e947 | 45 | #include "xattr.h" |
2e635a27 | 46 | |
5f39d397 | 47 | #define BTRFS_SUPER_MAGIC 0x9123683E |
f254e52c | 48 | |
39279cc3 | 49 | static struct super_operations btrfs_super_ops; |
75dfe396 | 50 | |
39279cc3 | 51 | static void btrfs_put_super (struct super_block * sb) |
b18c6685 | 52 | { |
39279cc3 | 53 | struct btrfs_root *root = btrfs_sb(sb); |
58176a96 | 54 | struct btrfs_fs_info *fs = root->fs_info; |
b18c6685 | 55 | int ret; |
b18c6685 | 56 | |
39279cc3 CM |
57 | ret = close_ctree(root); |
58 | if (ret) { | |
59 | printk("close ctree returns %d\n", ret); | |
75dfe396 | 60 | } |
58176a96 | 61 | btrfs_sysfs_del_super(fs); |
39279cc3 | 62 | sb->s_fs_info = NULL; |
75dfe396 CM |
63 | } |
64 | ||
95e05289 | 65 | enum { |
8f662a76 | 66 | Opt_subvol, Opt_nodatasum, Opt_nodatacow, Opt_max_extent, |
e18e4809 | 67 | Opt_alloc_start, Opt_nobarrier, Opt_ssd, Opt_err, |
95e05289 CM |
68 | }; |
69 | ||
70 | static match_table_t tokens = { | |
71 | {Opt_subvol, "subvol=%s"}, | |
b6cda9bc | 72 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 73 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 74 | {Opt_nobarrier, "nobarrier"}, |
c59f8951 | 75 | {Opt_max_extent, "max_extent=%s"}, |
8f662a76 | 76 | {Opt_alloc_start, "alloc_start=%s"}, |
e18e4809 | 77 | {Opt_ssd, "ssd"}, |
95e05289 CM |
78 | {Opt_err, NULL} |
79 | }; | |
80 | ||
edbd8d4e | 81 | u64 btrfs_parse_size(char *str) |
c59f8951 | 82 | { |
edbd8d4e | 83 | u64 res; |
c59f8951 CM |
84 | int mult = 1; |
85 | char *end; | |
86 | char last; | |
87 | ||
88 | res = simple_strtoul(str, &end, 10); | |
89 | ||
90 | last = end[0]; | |
91 | if (isalpha(last)) { | |
92 | last = tolower(last); | |
93 | switch (last) { | |
94 | case 'g': | |
95 | mult *= 1024; | |
96 | case 'm': | |
97 | mult *= 1024; | |
98 | case 'k': | |
99 | mult *= 1024; | |
100 | } | |
101 | res = res * mult; | |
102 | } | |
103 | return res; | |
104 | } | |
105 | ||
95e05289 CM |
106 | static int parse_options (char * options, |
107 | struct btrfs_root *root, | |
108 | char **subvol_name) | |
109 | { | |
110 | char * p; | |
b6cda9bc | 111 | struct btrfs_fs_info *info = NULL; |
95e05289 | 112 | substring_t args[MAX_OPT_ARGS]; |
b6cda9bc | 113 | |
95e05289 CM |
114 | if (!options) |
115 | return 1; | |
116 | ||
be20aa9d CM |
117 | /* |
118 | * strsep changes the string, duplicate it because parse_options | |
119 | * gets called twice | |
120 | */ | |
121 | options = kstrdup(options, GFP_NOFS); | |
122 | if (!options) | |
123 | return -ENOMEM; | |
124 | ||
125 | if (root) | |
126 | info = root->fs_info; | |
127 | ||
95e05289 CM |
128 | while ((p = strsep (&options, ",")) != NULL) { |
129 | int token; | |
130 | if (!*p) | |
131 | continue; | |
132 | ||
133 | token = match_token(p, tokens, args); | |
134 | switch (token) { | |
135 | case Opt_subvol: | |
be20aa9d | 136 | if (subvol_name) { |
b6cda9bc | 137 | *subvol_name = match_strdup(&args[0]); |
be20aa9d | 138 | } |
b6cda9bc CM |
139 | break; |
140 | case Opt_nodatasum: | |
be20aa9d CM |
141 | if (info) { |
142 | printk("btrfs: setting nodatacsum\n"); | |
b6cda9bc | 143 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
144 | } |
145 | break; | |
146 | case Opt_nodatacow: | |
147 | if (info) { | |
148 | printk("btrfs: setting nodatacow\n"); | |
149 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
150 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
151 | } | |
95e05289 | 152 | break; |
e18e4809 CM |
153 | case Opt_ssd: |
154 | if (info) { | |
155 | printk("btrfs: use ssd allocation scheme\n"); | |
156 | btrfs_set_opt(info->mount_opt, SSD); | |
157 | } | |
158 | break; | |
21ad10cf CM |
159 | case Opt_nobarrier: |
160 | if (info) { | |
161 | printk("btrfs: turning off barriers\n"); | |
162 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
163 | } | |
164 | break; | |
c59f8951 CM |
165 | case Opt_max_extent: |
166 | if (info) { | |
167 | char *num = match_strdup(&args[0]); | |
168 | if (num) { | |
edbd8d4e CM |
169 | info->max_extent = |
170 | btrfs_parse_size(num); | |
c59f8951 CM |
171 | kfree(num); |
172 | ||
173 | info->max_extent = max_t(u64, | |
174 | info->max_extent, | |
175 | root->sectorsize); | |
176 | printk("btrfs: max_extent at %Lu\n", | |
177 | info->max_extent); | |
178 | } | |
179 | } | |
180 | break; | |
8f662a76 CM |
181 | case Opt_alloc_start: |
182 | if (info) { | |
183 | char *num = match_strdup(&args[0]); | |
184 | if (num) { | |
185 | info->alloc_start = | |
186 | btrfs_parse_size(num); | |
187 | kfree(num); | |
188 | printk("btrfs: allocations start at " | |
189 | "%Lu\n", info->alloc_start); | |
190 | } | |
191 | } | |
192 | break; | |
95e05289 | 193 | default: |
be20aa9d | 194 | break; |
95e05289 CM |
195 | } |
196 | } | |
be20aa9d | 197 | kfree(options); |
95e05289 CM |
198 | return 1; |
199 | } | |
200 | ||
39279cc3 | 201 | static int btrfs_fill_super(struct super_block * sb, void * data, int silent) |
75dfe396 | 202 | { |
39279cc3 CM |
203 | struct inode * inode; |
204 | struct dentry * root_dentry; | |
205 | struct btrfs_super_block *disk_super; | |
206 | struct btrfs_root *tree_root; | |
207 | struct btrfs_inode *bi; | |
208 | int err; | |
a429e513 | 209 | |
39279cc3 CM |
210 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
211 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
212 | sb->s_op = &btrfs_super_ops; | |
5103e947 | 213 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 214 | sb->s_time_gran = 1; |
a429e513 | 215 | |
39279cc3 | 216 | tree_root = open_ctree(sb); |
6567e837 | 217 | |
39279cc3 CM |
218 | if (!tree_root || IS_ERR(tree_root)) { |
219 | printk("btrfs: open_ctree failed\n"); | |
220 | return -EIO; | |
a429e513 | 221 | } |
39279cc3 | 222 | sb->s_fs_info = tree_root; |
5f39d397 | 223 | disk_super = &tree_root->fs_info->super_copy; |
39279cc3 CM |
224 | inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super), |
225 | tree_root); | |
226 | bi = BTRFS_I(inode); | |
227 | bi->location.objectid = inode->i_ino; | |
228 | bi->location.offset = 0; | |
39279cc3 | 229 | bi->root = tree_root; |
b888db2b | 230 | |
39279cc3 | 231 | btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY); |
a429e513 | 232 | |
39279cc3 | 233 | if (!inode) { |
6567e837 | 234 | err = -ENOMEM; |
39279cc3 | 235 | goto fail_close; |
f254e52c | 236 | } |
39279cc3 CM |
237 | if (inode->i_state & I_NEW) { |
238 | btrfs_read_locked_inode(inode); | |
239 | unlock_new_inode(inode); | |
f254e52c | 240 | } |
f254e52c | 241 | |
39279cc3 CM |
242 | root_dentry = d_alloc_root(inode); |
243 | if (!root_dentry) { | |
244 | iput(inode); | |
245 | err = -ENOMEM; | |
246 | goto fail_close; | |
f254e52c | 247 | } |
58176a96 | 248 | |
b6cda9bc CM |
249 | parse_options((char *)data, tree_root, NULL); |
250 | ||
58176a96 JB |
251 | /* this does the super kobj at the same time */ |
252 | err = btrfs_sysfs_add_super(tree_root->fs_info); | |
253 | if (err) | |
254 | goto fail_close; | |
255 | ||
39279cc3 CM |
256 | sb->s_root = root_dentry; |
257 | btrfs_transaction_queue_work(tree_root, HZ * 30); | |
2619ba1f | 258 | return 0; |
39279cc3 CM |
259 | |
260 | fail_close: | |
261 | close_ctree(tree_root); | |
262 | return err; | |
2619ba1f CM |
263 | } |
264 | ||
39279cc3 | 265 | static int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
266 | { |
267 | struct btrfs_trans_handle *trans; | |
39279cc3 | 268 | struct btrfs_root *root; |
c5739bba | 269 | int ret; |
39279cc3 | 270 | root = btrfs_sb(sb); |
2619ba1f | 271 | |
39279cc3 CM |
272 | sb->s_dirt = 0; |
273 | if (!wait) { | |
274 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
275 | return 0; | |
276 | } | |
e9d0b13b | 277 | btrfs_clean_old_snapshots(root); |
c5739bba | 278 | mutex_lock(&root->fs_info->fs_mutex); |
e9d0b13b | 279 | btrfs_defrag_dirty_roots(root->fs_info); |
c5739bba | 280 | trans = btrfs_start_transaction(root, 1); |
c5739bba | 281 | ret = btrfs_commit_transaction(trans, root); |
39279cc3 | 282 | sb->s_dirt = 0; |
c5739bba | 283 | mutex_unlock(&root->fs_info->fs_mutex); |
54aa1f4d | 284 | return ret; |
2c90e5d6 CM |
285 | } |
286 | ||
39279cc3 | 287 | static void btrfs_write_super(struct super_block *sb) |
2c90e5d6 | 288 | { |
39279cc3 | 289 | sb->s_dirt = 0; |
2c90e5d6 CM |
290 | } |
291 | ||
4b82d6e4 Y |
292 | /* |
293 | * This is almost a copy of get_sb_bdev in fs/super.c. | |
294 | * We need the local copy to allow direct mounting of | |
295 | * subvolumes, but this could be easily integrated back | |
296 | * into the generic version. --hch | |
297 | */ | |
298 | ||
299 | /* start copy & paste */ | |
300 | static int set_bdev_super(struct super_block *s, void *data) | |
301 | { | |
302 | s->s_bdev = data; | |
303 | s->s_dev = s->s_bdev->bd_dev; | |
304 | return 0; | |
305 | } | |
306 | ||
307 | static int test_bdev_super(struct super_block *s, void *data) | |
308 | { | |
309 | return (void *)s->s_bdev == data; | |
310 | } | |
311 | ||
312 | int btrfs_get_sb_bdev(struct file_system_type *fs_type, | |
313 | int flags, const char *dev_name, void *data, | |
314 | int (*fill_super)(struct super_block *, void *, int), | |
315 | struct vfsmount *mnt, const char *subvol) | |
316 | { | |
317 | struct block_device *bdev = NULL; | |
318 | struct super_block *s; | |
319 | struct dentry *root; | |
320 | int error = 0; | |
321 | ||
322 | bdev = open_bdev_excl(dev_name, flags, fs_type); | |
323 | if (IS_ERR(bdev)) | |
324 | return PTR_ERR(bdev); | |
325 | ||
326 | /* | |
327 | * once the super is inserted into the list by sget, s_umount | |
328 | * will protect the lockfs code from trying to start a snapshot | |
329 | * while we are mounting | |
330 | */ | |
331 | down(&bdev->bd_mount_sem); | |
332 | s = sget(fs_type, test_bdev_super, set_bdev_super, bdev); | |
333 | up(&bdev->bd_mount_sem); | |
334 | if (IS_ERR(s)) | |
335 | goto error_s; | |
336 | ||
337 | if (s->s_root) { | |
338 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
339 | up_write(&s->s_umount); | |
340 | deactivate_super(s); | |
341 | error = -EBUSY; | |
342 | goto error_bdev; | |
343 | } | |
344 | ||
345 | close_bdev_excl(bdev); | |
346 | } else { | |
347 | char b[BDEVNAME_SIZE]; | |
348 | ||
349 | s->s_flags = flags; | |
350 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
351 | sb_set_blocksize(s, block_size(bdev)); | |
352 | error = fill_super(s, data, flags & MS_SILENT ? 1 : 0); | |
353 | if (error) { | |
354 | up_write(&s->s_umount); | |
355 | deactivate_super(s); | |
356 | goto error; | |
357 | } | |
358 | ||
359 | s->s_flags |= MS_ACTIVE; | |
360 | } | |
361 | ||
362 | if (subvol) { | |
363 | root = lookup_one_len(subvol, s->s_root, strlen(subvol)); | |
364 | if (IS_ERR(root)) { | |
365 | up_write(&s->s_umount); | |
366 | deactivate_super(s); | |
367 | error = PTR_ERR(root); | |
368 | goto error; | |
369 | } | |
370 | if (!root->d_inode) { | |
371 | dput(root); | |
372 | up_write(&s->s_umount); | |
373 | deactivate_super(s); | |
374 | error = -ENXIO; | |
375 | goto error; | |
376 | } | |
377 | } else { | |
378 | root = dget(s->s_root); | |
379 | } | |
380 | ||
381 | mnt->mnt_sb = s; | |
382 | mnt->mnt_root = root; | |
383 | return 0; | |
384 | ||
385 | error_s: | |
386 | error = PTR_ERR(s); | |
387 | error_bdev: | |
388 | close_bdev_excl(bdev); | |
389 | error: | |
390 | return error; | |
391 | } | |
392 | /* end copy & paste */ | |
393 | ||
2e635a27 | 394 | static int btrfs_get_sb(struct file_system_type *fs_type, |
95e05289 | 395 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) |
2e635a27 | 396 | { |
4b82d6e4 | 397 | int ret; |
95e05289 | 398 | char *subvol_name = NULL; |
4b82d6e4 | 399 | |
95e05289 | 400 | parse_options((char *)data, NULL, &subvol_name); |
4b82d6e4 Y |
401 | ret = btrfs_get_sb_bdev(fs_type, flags, dev_name, data, |
402 | btrfs_fill_super, mnt, | |
403 | subvol_name ? subvol_name : "default"); | |
c59f8951 CM |
404 | if (subvol_name) |
405 | kfree(subvol_name); | |
4b82d6e4 | 406 | return ret; |
2e635a27 CM |
407 | } |
408 | ||
8fd17795 CM |
409 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
410 | { | |
411 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 412 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
db94535d | 413 | int bits = dentry->d_sb->s_blocksize_bits; |
8fd17795 CM |
414 | |
415 | buf->f_namelen = BTRFS_NAME_LEN; | |
db94535d CM |
416 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
417 | buf->f_bfree = buf->f_blocks - | |
418 | (btrfs_super_bytes_used(disk_super) >> bits); | |
8fd17795 CM |
419 | buf->f_bavail = buf->f_bfree; |
420 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
421 | buf->f_type = BTRFS_SUPER_MAGIC; | |
422 | return 0; | |
423 | } | |
b5133862 | 424 | |
2e635a27 CM |
425 | static struct file_system_type btrfs_fs_type = { |
426 | .owner = THIS_MODULE, | |
427 | .name = "btrfs", | |
428 | .get_sb = btrfs_get_sb, | |
429 | .kill_sb = kill_block_super, | |
430 | .fs_flags = FS_REQUIRES_DEV, | |
431 | }; | |
432 | ||
e20d96d6 | 433 | static struct super_operations btrfs_super_ops = { |
134e9731 | 434 | .delete_inode = btrfs_delete_inode, |
2da98f00 | 435 | .put_inode = btrfs_put_inode, |
e20d96d6 CM |
436 | .put_super = btrfs_put_super, |
437 | .read_inode = btrfs_read_locked_inode, | |
d5719762 CM |
438 | .write_super = btrfs_write_super, |
439 | .sync_fs = btrfs_sync_fs, | |
4730a4bc | 440 | .write_inode = btrfs_write_inode, |
b5133862 | 441 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
442 | .alloc_inode = btrfs_alloc_inode, |
443 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 444 | .statfs = btrfs_statfs, |
e20d96d6 CM |
445 | }; |
446 | ||
2e635a27 CM |
447 | static int __init init_btrfs_fs(void) |
448 | { | |
2c90e5d6 | 449 | int err; |
58176a96 JB |
450 | |
451 | err = btrfs_init_sysfs(); | |
452 | if (err) | |
453 | return err; | |
454 | ||
08607c1b | 455 | btrfs_init_transaction_sys(); |
39279cc3 | 456 | err = btrfs_init_cachep(); |
2c90e5d6 | 457 | if (err) |
2f4cbe64 WB |
458 | goto free_transaction_sys; |
459 | err = extent_map_init(); | |
460 | if (err) | |
461 | goto free_cachep; | |
462 | ||
463 | err = register_filesystem(&btrfs_fs_type); | |
464 | if (err) | |
465 | goto free_extent_map; | |
466 | return 0; | |
467 | ||
468 | free_extent_map: | |
469 | extent_map_exit(); | |
470 | free_cachep: | |
471 | btrfs_destroy_cachep(); | |
472 | free_transaction_sys: | |
473 | btrfs_exit_transaction_sys(); | |
474 | btrfs_exit_sysfs(); | |
475 | return err; | |
2e635a27 CM |
476 | } |
477 | ||
478 | static void __exit exit_btrfs_fs(void) | |
479 | { | |
08607c1b | 480 | btrfs_exit_transaction_sys(); |
39279cc3 | 481 | btrfs_destroy_cachep(); |
a52d9a80 | 482 | extent_map_exit(); |
2e635a27 | 483 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 484 | btrfs_exit_sysfs(); |
2e635a27 CM |
485 | } |
486 | ||
487 | module_init(init_btrfs_fs) | |
488 | module_exit(exit_btrfs_fs) | |
489 | ||
490 | MODULE_LICENSE("GPL"); |