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