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 | 28 | #include <linux/string.h> |
2e635a27 | 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> |
1bcbf313 | 40 | #include <linux/magic.h> |
5a0e3ad6 | 41 | #include <linux/slab.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 | |
1abe9b8a | 55 | #define CREATE_TRACE_POINTS |
56 | #include <trace/events/btrfs.h> | |
57 | ||
b87221de | 58 | static const struct super_operations btrfs_super_ops; |
75dfe396 | 59 | |
acce952b | 60 | static const char *btrfs_decode_error(struct btrfs_fs_info *fs_info, int errno, |
61 | char nbuf[16]) | |
62 | { | |
63 | char *errstr = NULL; | |
64 | ||
65 | switch (errno) { | |
66 | case -EIO: | |
67 | errstr = "IO failure"; | |
68 | break; | |
69 | case -ENOMEM: | |
70 | errstr = "Out of memory"; | |
71 | break; | |
72 | case -EROFS: | |
73 | errstr = "Readonly filesystem"; | |
74 | break; | |
75 | default: | |
76 | if (nbuf) { | |
77 | if (snprintf(nbuf, 16, "error %d", -errno) >= 0) | |
78 | errstr = nbuf; | |
79 | } | |
80 | break; | |
81 | } | |
82 | ||
83 | return errstr; | |
84 | } | |
85 | ||
86 | static void __save_error_info(struct btrfs_fs_info *fs_info) | |
87 | { | |
88 | /* | |
89 | * today we only save the error info into ram. Long term we'll | |
90 | * also send it down to the disk | |
91 | */ | |
92 | fs_info->fs_state = BTRFS_SUPER_FLAG_ERROR; | |
93 | } | |
94 | ||
95 | /* NOTE: | |
96 | * We move write_super stuff at umount in order to avoid deadlock | |
97 | * for umount hold all lock. | |
98 | */ | |
99 | static void save_error_info(struct btrfs_fs_info *fs_info) | |
100 | { | |
101 | __save_error_info(fs_info); | |
102 | } | |
103 | ||
104 | /* btrfs handle error by forcing the filesystem readonly */ | |
105 | static void btrfs_handle_error(struct btrfs_fs_info *fs_info) | |
106 | { | |
107 | struct super_block *sb = fs_info->sb; | |
108 | ||
109 | if (sb->s_flags & MS_RDONLY) | |
110 | return; | |
111 | ||
112 | if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) { | |
113 | sb->s_flags |= MS_RDONLY; | |
114 | printk(KERN_INFO "btrfs is forced readonly\n"); | |
115 | } | |
116 | } | |
117 | ||
118 | /* | |
119 | * __btrfs_std_error decodes expected errors from the caller and | |
120 | * invokes the approciate error response. | |
121 | */ | |
122 | void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function, | |
123 | unsigned int line, int errno) | |
124 | { | |
125 | struct super_block *sb = fs_info->sb; | |
126 | char nbuf[16]; | |
127 | const char *errstr; | |
128 | ||
129 | /* | |
130 | * Special case: if the error is EROFS, and we're already | |
131 | * under MS_RDONLY, then it is safe here. | |
132 | */ | |
133 | if (errno == -EROFS && (sb->s_flags & MS_RDONLY)) | |
134 | return; | |
135 | ||
136 | errstr = btrfs_decode_error(fs_info, errno, nbuf); | |
137 | printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s\n", | |
138 | sb->s_id, function, line, errstr); | |
139 | save_error_info(fs_info); | |
140 | ||
141 | btrfs_handle_error(fs_info); | |
142 | } | |
143 | ||
d397712b | 144 | static void btrfs_put_super(struct super_block *sb) |
b18c6685 | 145 | { |
39279cc3 | 146 | struct btrfs_root *root = btrfs_sb(sb); |
b18c6685 | 147 | int ret; |
b18c6685 | 148 | |
39279cc3 | 149 | ret = close_ctree(root); |
39279cc3 | 150 | sb->s_fs_info = NULL; |
559af821 AK |
151 | |
152 | (void)ret; /* FIXME: need to fix VFS to return error? */ | |
75dfe396 CM |
153 | } |
154 | ||
95e05289 | 155 | enum { |
73f73415 | 156 | Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, |
287a0ab9 JB |
157 | Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, |
158 | Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, | |
261507a0 LZ |
159 | Opt_compress_type, Opt_compress_force, Opt_compress_force_type, |
160 | Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, | |
91435650 CM |
161 | Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, |
162 | Opt_enospc_debug, Opt_err, | |
95e05289 CM |
163 | }; |
164 | ||
165 | static match_table_t tokens = { | |
dfe25020 | 166 | {Opt_degraded, "degraded"}, |
95e05289 | 167 | {Opt_subvol, "subvol=%s"}, |
73f73415 | 168 | {Opt_subvolid, "subvolid=%d"}, |
43e570b0 | 169 | {Opt_device, "device=%s"}, |
b6cda9bc | 170 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 171 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 172 | {Opt_nobarrier, "nobarrier"}, |
6f568d35 | 173 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 174 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 175 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 176 | {Opt_compress, "compress"}, |
261507a0 | 177 | {Opt_compress_type, "compress=%s"}, |
a555f810 | 178 | {Opt_compress_force, "compress-force"}, |
261507a0 | 179 | {Opt_compress_force_type, "compress-force=%s"}, |
e18e4809 | 180 | {Opt_ssd, "ssd"}, |
451d7585 | 181 | {Opt_ssd_spread, "ssd_spread"}, |
3b30c22f | 182 | {Opt_nossd, "nossd"}, |
33268eaf | 183 | {Opt_noacl, "noacl"}, |
3a5e1404 | 184 | {Opt_notreelog, "notreelog"}, |
dccae999 | 185 | {Opt_flushoncommit, "flushoncommit"}, |
97e728d4 | 186 | {Opt_ratio, "metadata_ratio=%d"}, |
e244a0ae | 187 | {Opt_discard, "discard"}, |
0af3d00b | 188 | {Opt_space_cache, "space_cache"}, |
88c2ba3b | 189 | {Opt_clear_cache, "clear_cache"}, |
4260f7c7 | 190 | {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, |
91435650 | 191 | {Opt_enospc_debug, "enospc_debug"}, |
33268eaf | 192 | {Opt_err, NULL}, |
95e05289 CM |
193 | }; |
194 | ||
edf24abe CH |
195 | /* |
196 | * Regular mount options parser. Everything that is needed only when | |
197 | * reading in a new superblock is parsed here. | |
198 | */ | |
199 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 200 | { |
edf24abe | 201 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 202 | substring_t args[MAX_OPT_ARGS]; |
da495ecc | 203 | char *p, *num, *orig; |
4543df7e | 204 | int intarg; |
a7a3f7ca | 205 | int ret = 0; |
261507a0 LZ |
206 | char *compress_type; |
207 | bool compress_force = false; | |
b6cda9bc | 208 | |
95e05289 | 209 | if (!options) |
edf24abe | 210 | return 0; |
95e05289 | 211 | |
be20aa9d CM |
212 | /* |
213 | * strsep changes the string, duplicate it because parse_options | |
214 | * gets called twice | |
215 | */ | |
216 | options = kstrdup(options, GFP_NOFS); | |
217 | if (!options) | |
218 | return -ENOMEM; | |
219 | ||
da495ecc | 220 | orig = options; |
be20aa9d | 221 | |
edf24abe | 222 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
223 | int token; |
224 | if (!*p) | |
225 | continue; | |
226 | ||
227 | token = match_token(p, tokens, args); | |
228 | switch (token) { | |
dfe25020 | 229 | case Opt_degraded: |
edf24abe CH |
230 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
231 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 232 | break; |
95e05289 | 233 | case Opt_subvol: |
73f73415 | 234 | case Opt_subvolid: |
43e570b0 | 235 | case Opt_device: |
edf24abe | 236 | /* |
43e570b0 | 237 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
238 | * and can be happily ignored here. |
239 | */ | |
b6cda9bc CM |
240 | break; |
241 | case Opt_nodatasum: | |
067c28ad | 242 | printk(KERN_INFO "btrfs: setting nodatasum\n"); |
edf24abe | 243 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
244 | break; |
245 | case Opt_nodatacow: | |
edf24abe CH |
246 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
247 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
248 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 249 | break; |
a555f810 | 250 | case Opt_compress_force: |
261507a0 LZ |
251 | case Opt_compress_force_type: |
252 | compress_force = true; | |
253 | case Opt_compress: | |
254 | case Opt_compress_type: | |
255 | if (token == Opt_compress || | |
256 | token == Opt_compress_force || | |
257 | strcmp(args[0].from, "zlib") == 0) { | |
258 | compress_type = "zlib"; | |
259 | info->compress_type = BTRFS_COMPRESS_ZLIB; | |
a6fa6fae LZ |
260 | } else if (strcmp(args[0].from, "lzo") == 0) { |
261 | compress_type = "lzo"; | |
262 | info->compress_type = BTRFS_COMPRESS_LZO; | |
261507a0 LZ |
263 | } else { |
264 | ret = -EINVAL; | |
265 | goto out; | |
266 | } | |
267 | ||
a555f810 | 268 | btrfs_set_opt(info->mount_opt, COMPRESS); |
261507a0 LZ |
269 | if (compress_force) { |
270 | btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); | |
271 | pr_info("btrfs: force %s compression\n", | |
272 | compress_type); | |
273 | } else | |
274 | pr_info("btrfs: use %s compression\n", | |
275 | compress_type); | |
a555f810 | 276 | break; |
e18e4809 | 277 | case Opt_ssd: |
edf24abe CH |
278 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
279 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 280 | break; |
451d7585 CM |
281 | case Opt_ssd_spread: |
282 | printk(KERN_INFO "btrfs: use spread ssd " | |
283 | "allocation scheme\n"); | |
284 | btrfs_set_opt(info->mount_opt, SSD); | |
285 | btrfs_set_opt(info->mount_opt, SSD_SPREAD); | |
286 | break; | |
3b30c22f | 287 | case Opt_nossd: |
451d7585 CM |
288 | printk(KERN_INFO "btrfs: not using ssd allocation " |
289 | "scheme\n"); | |
c289811c | 290 | btrfs_set_opt(info->mount_opt, NOSSD); |
3b30c22f | 291 | btrfs_clear_opt(info->mount_opt, SSD); |
451d7585 | 292 | btrfs_clear_opt(info->mount_opt, SSD_SPREAD); |
3b30c22f | 293 | break; |
21ad10cf | 294 | case Opt_nobarrier: |
edf24abe CH |
295 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
296 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 297 | break; |
4543df7e CM |
298 | case Opt_thread_pool: |
299 | intarg = 0; | |
300 | match_int(&args[0], &intarg); | |
301 | if (intarg) { | |
302 | info->thread_pool_size = intarg; | |
303 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
304 | info->thread_pool_size); | |
305 | } | |
306 | break; | |
6f568d35 | 307 | case Opt_max_inline: |
edf24abe CH |
308 | num = match_strdup(&args[0]); |
309 | if (num) { | |
91748467 | 310 | info->max_inline = memparse(num, NULL); |
edf24abe CH |
311 | kfree(num); |
312 | ||
15ada040 CM |
313 | if (info->max_inline) { |
314 | info->max_inline = max_t(u64, | |
315 | info->max_inline, | |
316 | root->sectorsize); | |
317 | } | |
edf24abe | 318 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
21380931 | 319 | (unsigned long long)info->max_inline); |
6f568d35 CM |
320 | } |
321 | break; | |
8f662a76 | 322 | case Opt_alloc_start: |
edf24abe CH |
323 | num = match_strdup(&args[0]); |
324 | if (num) { | |
91748467 | 325 | info->alloc_start = memparse(num, NULL); |
edf24abe CH |
326 | kfree(num); |
327 | printk(KERN_INFO | |
328 | "btrfs: allocations start at %llu\n", | |
21380931 | 329 | (unsigned long long)info->alloc_start); |
8f662a76 CM |
330 | } |
331 | break; | |
33268eaf JB |
332 | case Opt_noacl: |
333 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
334 | break; | |
3a5e1404 SW |
335 | case Opt_notreelog: |
336 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
337 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
338 | break; | |
dccae999 SW |
339 | case Opt_flushoncommit: |
340 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
341 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
342 | break; | |
97e728d4 JB |
343 | case Opt_ratio: |
344 | intarg = 0; | |
345 | match_int(&args[0], &intarg); | |
346 | if (intarg) { | |
347 | info->metadata_ratio = intarg; | |
348 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
349 | info->metadata_ratio); | |
350 | } | |
351 | break; | |
e244a0ae CH |
352 | case Opt_discard: |
353 | btrfs_set_opt(info->mount_opt, DISCARD); | |
354 | break; | |
0af3d00b JB |
355 | case Opt_space_cache: |
356 | printk(KERN_INFO "btrfs: enabling disk space caching\n"); | |
357 | btrfs_set_opt(info->mount_opt, SPACE_CACHE); | |
0de90876 | 358 | break; |
88c2ba3b JB |
359 | case Opt_clear_cache: |
360 | printk(KERN_INFO "btrfs: force clearing of disk cache\n"); | |
361 | btrfs_set_opt(info->mount_opt, CLEAR_CACHE); | |
0af3d00b | 362 | break; |
4260f7c7 SW |
363 | case Opt_user_subvol_rm_allowed: |
364 | btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); | |
365 | break; | |
91435650 CM |
366 | case Opt_enospc_debug: |
367 | btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); | |
368 | break; | |
a7a3f7ca SW |
369 | case Opt_err: |
370 | printk(KERN_INFO "btrfs: unrecognized mount option " | |
371 | "'%s'\n", p); | |
372 | ret = -EINVAL; | |
373 | goto out; | |
95e05289 | 374 | default: |
be20aa9d | 375 | break; |
95e05289 CM |
376 | } |
377 | } | |
a7a3f7ca | 378 | out: |
da495ecc | 379 | kfree(orig); |
a7a3f7ca | 380 | return ret; |
edf24abe CH |
381 | } |
382 | ||
383 | /* | |
384 | * Parse mount options that are required early in the mount process. | |
385 | * | |
386 | * All other options will be parsed on much later in the mount process and | |
387 | * only when we need to allocate a new super block. | |
388 | */ | |
97288f2c | 389 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
73f73415 | 390 | void *holder, char **subvol_name, u64 *subvol_objectid, |
43e570b0 | 391 | struct btrfs_fs_devices **fs_devices) |
edf24abe CH |
392 | { |
393 | substring_t args[MAX_OPT_ARGS]; | |
3f3d0bc0 | 394 | char *opts, *orig, *p; |
edf24abe | 395 | int error = 0; |
73f73415 | 396 | int intarg; |
edf24abe CH |
397 | |
398 | if (!options) | |
399 | goto out; | |
400 | ||
401 | /* | |
402 | * strsep changes the string, duplicate it because parse_options | |
403 | * gets called twice | |
404 | */ | |
405 | opts = kstrdup(options, GFP_KERNEL); | |
406 | if (!opts) | |
407 | return -ENOMEM; | |
3f3d0bc0 | 408 | orig = opts; |
edf24abe CH |
409 | |
410 | while ((p = strsep(&opts, ",")) != NULL) { | |
411 | int token; | |
412 | if (!*p) | |
413 | continue; | |
414 | ||
415 | token = match_token(p, tokens, args); | |
416 | switch (token) { | |
417 | case Opt_subvol: | |
418 | *subvol_name = match_strdup(&args[0]); | |
419 | break; | |
73f73415 JB |
420 | case Opt_subvolid: |
421 | intarg = 0; | |
4849f01d JB |
422 | error = match_int(&args[0], &intarg); |
423 | if (!error) { | |
424 | /* we want the original fs_tree */ | |
425 | if (!intarg) | |
426 | *subvol_objectid = | |
427 | BTRFS_FS_TREE_OBJECTID; | |
428 | else | |
429 | *subvol_objectid = intarg; | |
430 | } | |
73f73415 | 431 | break; |
43e570b0 CH |
432 | case Opt_device: |
433 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
434 | flags, holder, fs_devices); | |
435 | if (error) | |
436 | goto out_free_opts; | |
437 | break; | |
edf24abe CH |
438 | default: |
439 | break; | |
440 | } | |
441 | } | |
442 | ||
43e570b0 | 443 | out_free_opts: |
3f3d0bc0 | 444 | kfree(orig); |
edf24abe CH |
445 | out: |
446 | /* | |
447 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 448 | * a copy of the string "." here so that code later in the |
edf24abe CH |
449 | * mount path doesn't care if it's the default volume or another one. |
450 | */ | |
451 | if (!*subvol_name) { | |
3de4586c | 452 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
453 | if (!*subvol_name) |
454 | return -ENOMEM; | |
455 | } | |
456 | return error; | |
95e05289 CM |
457 | } |
458 | ||
73f73415 JB |
459 | static struct dentry *get_default_root(struct super_block *sb, |
460 | u64 subvol_objectid) | |
461 | { | |
462 | struct btrfs_root *root = sb->s_fs_info; | |
463 | struct btrfs_root *new_root; | |
464 | struct btrfs_dir_item *di; | |
465 | struct btrfs_path *path; | |
466 | struct btrfs_key location; | |
467 | struct inode *inode; | |
468 | struct dentry *dentry; | |
469 | u64 dir_id; | |
470 | int new = 0; | |
471 | ||
472 | /* | |
473 | * We have a specific subvol we want to mount, just setup location and | |
474 | * go look up the root. | |
475 | */ | |
476 | if (subvol_objectid) { | |
477 | location.objectid = subvol_objectid; | |
478 | location.type = BTRFS_ROOT_ITEM_KEY; | |
479 | location.offset = (u64)-1; | |
480 | goto find_root; | |
481 | } | |
482 | ||
483 | path = btrfs_alloc_path(); | |
484 | if (!path) | |
485 | return ERR_PTR(-ENOMEM); | |
486 | path->leave_spinning = 1; | |
487 | ||
488 | /* | |
489 | * Find the "default" dir item which points to the root item that we | |
490 | * will mount by default if we haven't been given a specific subvolume | |
491 | * to mount. | |
492 | */ | |
493 | dir_id = btrfs_super_root_dir(&root->fs_info->super_copy); | |
494 | di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); | |
fb4f6f91 DC |
495 | if (IS_ERR(di)) |
496 | return ERR_CAST(di); | |
73f73415 JB |
497 | if (!di) { |
498 | /* | |
499 | * Ok the default dir item isn't there. This is weird since | |
500 | * it's always been there, but don't freak out, just try and | |
501 | * mount to root most subvolume. | |
502 | */ | |
503 | btrfs_free_path(path); | |
504 | dir_id = BTRFS_FIRST_FREE_OBJECTID; | |
505 | new_root = root->fs_info->fs_root; | |
506 | goto setup_root; | |
507 | } | |
508 | ||
509 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); | |
510 | btrfs_free_path(path); | |
511 | ||
512 | find_root: | |
513 | new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); | |
514 | if (IS_ERR(new_root)) | |
d0b678cb | 515 | return ERR_CAST(new_root); |
73f73415 JB |
516 | |
517 | if (btrfs_root_refs(&new_root->root_item) == 0) | |
518 | return ERR_PTR(-ENOENT); | |
519 | ||
520 | dir_id = btrfs_root_dirid(&new_root->root_item); | |
521 | setup_root: | |
522 | location.objectid = dir_id; | |
523 | location.type = BTRFS_INODE_ITEM_KEY; | |
524 | location.offset = 0; | |
525 | ||
526 | inode = btrfs_iget(sb, &location, new_root, &new); | |
4cbd1149 DC |
527 | if (IS_ERR(inode)) |
528 | return ERR_CAST(inode); | |
73f73415 JB |
529 | |
530 | /* | |
531 | * If we're just mounting the root most subvol put the inode and return | |
532 | * a reference to the dentry. We will have already gotten a reference | |
533 | * to the inode in btrfs_fill_super so we're good to go. | |
534 | */ | |
535 | if (!new && sb->s_root->d_inode == inode) { | |
536 | iput(inode); | |
537 | return dget(sb->s_root); | |
538 | } | |
539 | ||
540 | if (new) { | |
541 | const struct qstr name = { .name = "/", .len = 1 }; | |
542 | ||
543 | /* | |
544 | * New inode, we need to make the dentry a sibling of s_root so | |
545 | * everything gets cleaned up properly on unmount. | |
546 | */ | |
547 | dentry = d_alloc(sb->s_root, &name); | |
548 | if (!dentry) { | |
549 | iput(inode); | |
550 | return ERR_PTR(-ENOMEM); | |
551 | } | |
552 | d_splice_alias(inode, dentry); | |
553 | } else { | |
554 | /* | |
555 | * We found the inode in cache, just find a dentry for it and | |
556 | * put the reference to the inode we just got. | |
557 | */ | |
558 | dentry = d_find_alias(inode); | |
559 | iput(inode); | |
560 | } | |
561 | ||
562 | return dentry; | |
563 | } | |
564 | ||
d397712b | 565 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 566 | struct btrfs_fs_devices *fs_devices, |
d397712b | 567 | void *data, int silent) |
75dfe396 | 568 | { |
d397712b CM |
569 | struct inode *inode; |
570 | struct dentry *root_dentry; | |
39279cc3 | 571 | struct btrfs_root *tree_root; |
5d4f98a2 | 572 | struct btrfs_key key; |
39279cc3 | 573 | int err; |
a429e513 | 574 | |
39279cc3 CM |
575 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
576 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
577 | sb->s_op = &btrfs_super_ops; | |
af53d29a | 578 | sb->s_d_op = &btrfs_dentry_operations; |
be6e8dc0 | 579 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 580 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 581 | sb->s_time_gran = 1; |
0eda294d | 582 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
33268eaf | 583 | sb->s_flags |= MS_POSIXACL; |
49cf6f45 | 584 | #endif |
a429e513 | 585 | |
dfe25020 | 586 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 587 | |
e58ca020 | 588 | if (IS_ERR(tree_root)) { |
39279cc3 | 589 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 590 | return PTR_ERR(tree_root); |
a429e513 | 591 | } |
39279cc3 | 592 | sb->s_fs_info = tree_root; |
a429e513 | 593 | |
5d4f98a2 YZ |
594 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
595 | key.type = BTRFS_INODE_ITEM_KEY; | |
596 | key.offset = 0; | |
73f73415 | 597 | inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root, NULL); |
5d4f98a2 YZ |
598 | if (IS_ERR(inode)) { |
599 | err = PTR_ERR(inode); | |
39279cc3 | 600 | goto fail_close; |
f254e52c | 601 | } |
f254e52c | 602 | |
39279cc3 CM |
603 | root_dentry = d_alloc_root(inode); |
604 | if (!root_dentry) { | |
605 | iput(inode); | |
606 | err = -ENOMEM; | |
607 | goto fail_close; | |
f254e52c | 608 | } |
58176a96 | 609 | |
39279cc3 | 610 | sb->s_root = root_dentry; |
6885f308 | 611 | |
6885f308 | 612 | save_mount_options(sb, data); |
2619ba1f | 613 | return 0; |
39279cc3 CM |
614 | |
615 | fail_close: | |
616 | close_ctree(tree_root); | |
617 | return err; | |
2619ba1f CM |
618 | } |
619 | ||
6bf13c0c | 620 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
621 | { |
622 | struct btrfs_trans_handle *trans; | |
dccae999 | 623 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 624 | int ret; |
2619ba1f | 625 | |
1abe9b8a | 626 | trace_btrfs_sync_fs(wait); |
627 | ||
39279cc3 CM |
628 | if (!wait) { |
629 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
630 | return 0; | |
631 | } | |
771ed689 | 632 | |
24bbcf04 YZ |
633 | btrfs_start_delalloc_inodes(root, 0); |
634 | btrfs_wait_ordered_extents(root, 0, 0); | |
771ed689 | 635 | |
a22285a6 | 636 | trans = btrfs_start_transaction(root, 0); |
98d5dc13 TI |
637 | if (IS_ERR(trans)) |
638 | return PTR_ERR(trans); | |
c5739bba | 639 | ret = btrfs_commit_transaction(trans, root); |
54aa1f4d | 640 | return ret; |
2c90e5d6 CM |
641 | } |
642 | ||
a9572a15 EP |
643 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
644 | { | |
645 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
646 | struct btrfs_fs_info *info = root->fs_info; | |
200da64e | 647 | char *compress_type; |
a9572a15 EP |
648 | |
649 | if (btrfs_test_opt(root, DEGRADED)) | |
650 | seq_puts(seq, ",degraded"); | |
651 | if (btrfs_test_opt(root, NODATASUM)) | |
652 | seq_puts(seq, ",nodatasum"); | |
653 | if (btrfs_test_opt(root, NODATACOW)) | |
654 | seq_puts(seq, ",nodatacow"); | |
655 | if (btrfs_test_opt(root, NOBARRIER)) | |
656 | seq_puts(seq, ",nobarrier"); | |
a9572a15 | 657 | if (info->max_inline != 8192 * 1024) |
21380931 JB |
658 | seq_printf(seq, ",max_inline=%llu", |
659 | (unsigned long long)info->max_inline); | |
a9572a15 | 660 | if (info->alloc_start != 0) |
21380931 JB |
661 | seq_printf(seq, ",alloc_start=%llu", |
662 | (unsigned long long)info->alloc_start); | |
a9572a15 EP |
663 | if (info->thread_pool_size != min_t(unsigned long, |
664 | num_online_cpus() + 2, 8)) | |
665 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
200da64e TI |
666 | if (btrfs_test_opt(root, COMPRESS)) { |
667 | if (info->compress_type == BTRFS_COMPRESS_ZLIB) | |
668 | compress_type = "zlib"; | |
669 | else | |
670 | compress_type = "lzo"; | |
671 | if (btrfs_test_opt(root, FORCE_COMPRESS)) | |
672 | seq_printf(seq, ",compress-force=%s", compress_type); | |
673 | else | |
674 | seq_printf(seq, ",compress=%s", compress_type); | |
675 | } | |
c289811c CM |
676 | if (btrfs_test_opt(root, NOSSD)) |
677 | seq_puts(seq, ",nossd"); | |
451d7585 CM |
678 | if (btrfs_test_opt(root, SSD_SPREAD)) |
679 | seq_puts(seq, ",ssd_spread"); | |
680 | else if (btrfs_test_opt(root, SSD)) | |
a9572a15 | 681 | seq_puts(seq, ",ssd"); |
3a5e1404 | 682 | if (btrfs_test_opt(root, NOTREELOG)) |
6b65c5c6 | 683 | seq_puts(seq, ",notreelog"); |
dccae999 | 684 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
6b65c5c6 | 685 | seq_puts(seq, ",flushoncommit"); |
20a5239a MW |
686 | if (btrfs_test_opt(root, DISCARD)) |
687 | seq_puts(seq, ",discard"); | |
a9572a15 EP |
688 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
689 | seq_puts(seq, ",noacl"); | |
200da64e TI |
690 | if (btrfs_test_opt(root, SPACE_CACHE)) |
691 | seq_puts(seq, ",space_cache"); | |
692 | if (btrfs_test_opt(root, CLEAR_CACHE)) | |
693 | seq_puts(seq, ",clear_cache"); | |
694 | if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) | |
695 | seq_puts(seq, ",user_subvol_rm_allowed"); | |
a9572a15 EP |
696 | return 0; |
697 | } | |
698 | ||
a061fc8d | 699 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 700 | { |
450ba0ea | 701 | struct btrfs_root *test_root = data; |
a061fc8d | 702 | struct btrfs_root *root = btrfs_sb(s); |
4b82d6e4 | 703 | |
619c8c76 IK |
704 | /* |
705 | * If this super block is going away, return false as it | |
706 | * can't match as an existing super block. | |
707 | */ | |
708 | if (!atomic_read(&s->s_active)) | |
709 | return 0; | |
450ba0ea | 710 | return root->fs_info->fs_devices == test_root->fs_info->fs_devices; |
4b82d6e4 Y |
711 | } |
712 | ||
450ba0ea JB |
713 | static int btrfs_set_super(struct super_block *s, void *data) |
714 | { | |
715 | s->s_fs_info = data; | |
716 | ||
717 | return set_anon_super(s, data); | |
4b82d6e4 Y |
718 | } |
719 | ||
450ba0ea | 720 | |
edf24abe CH |
721 | /* |
722 | * Find a superblock for the given device / mount point. | |
723 | * | |
724 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
725 | * for multiple device setup. Make sure to keep it in sync. | |
726 | */ | |
061dbc6b AV |
727 | static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, |
728 | const char *dev_name, void *data) | |
4b82d6e4 Y |
729 | { |
730 | struct block_device *bdev = NULL; | |
731 | struct super_block *s; | |
732 | struct dentry *root; | |
8a4b83cc | 733 | struct btrfs_fs_devices *fs_devices = NULL; |
450ba0ea JB |
734 | struct btrfs_root *tree_root = NULL; |
735 | struct btrfs_fs_info *fs_info = NULL; | |
97288f2c | 736 | fmode_t mode = FMODE_READ; |
73f73415 JB |
737 | char *subvol_name = NULL; |
738 | u64 subvol_objectid = 0; | |
4b82d6e4 Y |
739 | int error = 0; |
740 | ||
97288f2c CH |
741 | if (!(flags & MS_RDONLY)) |
742 | mode |= FMODE_WRITE; | |
743 | ||
744 | error = btrfs_parse_early_options(data, mode, fs_type, | |
73f73415 JB |
745 | &subvol_name, &subvol_objectid, |
746 | &fs_devices); | |
edf24abe | 747 | if (error) |
061dbc6b | 748 | return ERR_PTR(error); |
edf24abe | 749 | |
97288f2c | 750 | error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices); |
8a4b83cc | 751 | if (error) |
edf24abe | 752 | goto error_free_subvol_name; |
4b82d6e4 | 753 | |
97288f2c | 754 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 755 | if (error) |
edf24abe | 756 | goto error_free_subvol_name; |
8a4b83cc | 757 | |
2b82032c YZ |
758 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
759 | error = -EACCES; | |
760 | goto error_close_devices; | |
761 | } | |
762 | ||
450ba0ea JB |
763 | /* |
764 | * Setup a dummy root and fs_info for test/set super. This is because | |
765 | * we don't actually fill this stuff out until open_ctree, but we need | |
766 | * it for searching for existing supers, so this lets us do that and | |
767 | * then open_ctree will properly initialize everything later. | |
768 | */ | |
769 | fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS); | |
770 | tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS); | |
771 | if (!fs_info || !tree_root) { | |
772 | error = -ENOMEM; | |
773 | goto error_close_devices; | |
774 | } | |
775 | fs_info->tree_root = tree_root; | |
776 | fs_info->fs_devices = fs_devices; | |
777 | tree_root->fs_info = fs_info; | |
778 | ||
dfe25020 | 779 | bdev = fs_devices->latest_bdev; |
450ba0ea | 780 | s = sget(fs_type, btrfs_test_super, btrfs_set_super, tree_root); |
4b82d6e4 Y |
781 | if (IS_ERR(s)) |
782 | goto error_s; | |
783 | ||
784 | if (s->s_root) { | |
785 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
6f5bbff9 | 786 | deactivate_locked_super(s); |
4b82d6e4 | 787 | error = -EBUSY; |
c146afad | 788 | goto error_close_devices; |
4b82d6e4 Y |
789 | } |
790 | ||
2b82032c | 791 | btrfs_close_devices(fs_devices); |
bdc924bb IK |
792 | kfree(fs_info); |
793 | kfree(tree_root); | |
4b82d6e4 Y |
794 | } else { |
795 | char b[BDEVNAME_SIZE]; | |
796 | ||
797 | s->s_flags = flags; | |
798 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
799 | error = btrfs_fill_super(s, fs_devices, data, |
800 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 | 801 | if (error) { |
6f5bbff9 | 802 | deactivate_locked_super(s); |
1f483660 | 803 | goto error_free_subvol_name; |
4b82d6e4 Y |
804 | } |
805 | ||
788f20eb | 806 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
807 | s->s_flags |= MS_ACTIVE; |
808 | } | |
809 | ||
73f73415 JB |
810 | root = get_default_root(s, subvol_objectid); |
811 | if (IS_ERR(root)) { | |
812 | error = PTR_ERR(root); | |
813 | deactivate_locked_super(s); | |
0e78340f | 814 | goto error_free_subvol_name; |
73f73415 JB |
815 | } |
816 | /* if they gave us a subvolume name bind mount into that */ | |
817 | if (strcmp(subvol_name, ".")) { | |
818 | struct dentry *new_root; | |
819 | mutex_lock(&root->d_inode->i_mutex); | |
820 | new_root = lookup_one_len(subvol_name, root, | |
d397712b | 821 | strlen(subvol_name)); |
73f73415 | 822 | mutex_unlock(&root->d_inode->i_mutex); |
d397712b | 823 | |
73f73415 | 824 | if (IS_ERR(new_root)) { |
f106e82c | 825 | dput(root); |
6f5bbff9 | 826 | deactivate_locked_super(s); |
73f73415 | 827 | error = PTR_ERR(new_root); |
0e78340f | 828 | goto error_free_subvol_name; |
76fcef19 | 829 | } |
73f73415 | 830 | if (!new_root->d_inode) { |
76fcef19 | 831 | dput(root); |
73f73415 | 832 | dput(new_root); |
6f5bbff9 | 833 | deactivate_locked_super(s); |
76fcef19 | 834 | error = -ENXIO; |
0e78340f | 835 | goto error_free_subvol_name; |
76fcef19 | 836 | } |
73f73415 JB |
837 | dput(root); |
838 | root = new_root; | |
4b82d6e4 Y |
839 | } |
840 | ||
edf24abe | 841 | kfree(subvol_name); |
061dbc6b | 842 | return root; |
4b82d6e4 Y |
843 | |
844 | error_s: | |
845 | error = PTR_ERR(s); | |
c146afad | 846 | error_close_devices: |
8a4b83cc | 847 | btrfs_close_devices(fs_devices); |
450ba0ea JB |
848 | kfree(fs_info); |
849 | kfree(tree_root); | |
edf24abe CH |
850 | error_free_subvol_name: |
851 | kfree(subvol_name); | |
061dbc6b | 852 | return ERR_PTR(error); |
4b82d6e4 | 853 | } |
2e635a27 | 854 | |
c146afad YZ |
855 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
856 | { | |
857 | struct btrfs_root *root = btrfs_sb(sb); | |
858 | int ret; | |
859 | ||
b288052e CM |
860 | ret = btrfs_parse_options(root, data); |
861 | if (ret) | |
862 | return -EINVAL; | |
863 | ||
c146afad YZ |
864 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
865 | return 0; | |
866 | ||
867 | if (*flags & MS_RDONLY) { | |
868 | sb->s_flags |= MS_RDONLY; | |
869 | ||
870 | ret = btrfs_commit_super(root); | |
871 | WARN_ON(ret); | |
872 | } else { | |
2b82032c YZ |
873 | if (root->fs_info->fs_devices->rw_devices == 0) |
874 | return -EACCES; | |
875 | ||
c146afad YZ |
876 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
877 | return -EINVAL; | |
878 | ||
d68fc57b | 879 | ret = btrfs_cleanup_fs_roots(root->fs_info); |
c146afad YZ |
880 | WARN_ON(ret); |
881 | ||
d68fc57b YZ |
882 | /* recover relocation */ |
883 | ret = btrfs_recover_relocation(root); | |
c146afad YZ |
884 | WARN_ON(ret); |
885 | ||
886 | sb->s_flags &= ~MS_RDONLY; | |
887 | } | |
888 | ||
889 | return 0; | |
890 | } | |
891 | ||
6d07bcec MX |
892 | /* |
893 | * The helper to calc the free space on the devices that can be used to store | |
894 | * file data. | |
895 | */ | |
896 | static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes) | |
897 | { | |
898 | struct btrfs_fs_info *fs_info = root->fs_info; | |
899 | struct btrfs_device_info *devices_info; | |
900 | struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; | |
901 | struct btrfs_device *device; | |
902 | u64 skip_space; | |
903 | u64 type; | |
904 | u64 avail_space; | |
905 | u64 used_space; | |
906 | u64 min_stripe_size; | |
907 | int min_stripes = 1; | |
908 | int i = 0, nr_devices; | |
909 | int ret; | |
910 | ||
911 | nr_devices = fs_info->fs_devices->rw_devices; | |
912 | BUG_ON(!nr_devices); | |
913 | ||
914 | devices_info = kmalloc(sizeof(*devices_info) * nr_devices, | |
915 | GFP_NOFS); | |
916 | if (!devices_info) | |
917 | return -ENOMEM; | |
918 | ||
919 | /* calc min stripe number for data space alloction */ | |
920 | type = btrfs_get_alloc_profile(root, 1); | |
921 | if (type & BTRFS_BLOCK_GROUP_RAID0) | |
922 | min_stripes = 2; | |
923 | else if (type & BTRFS_BLOCK_GROUP_RAID1) | |
924 | min_stripes = 2; | |
925 | else if (type & BTRFS_BLOCK_GROUP_RAID10) | |
926 | min_stripes = 4; | |
927 | ||
928 | if (type & BTRFS_BLOCK_GROUP_DUP) | |
929 | min_stripe_size = 2 * BTRFS_STRIPE_LEN; | |
930 | else | |
931 | min_stripe_size = BTRFS_STRIPE_LEN; | |
932 | ||
933 | list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { | |
934 | if (!device->in_fs_metadata) | |
935 | continue; | |
936 | ||
937 | avail_space = device->total_bytes - device->bytes_used; | |
938 | ||
939 | /* align with stripe_len */ | |
940 | do_div(avail_space, BTRFS_STRIPE_LEN); | |
941 | avail_space *= BTRFS_STRIPE_LEN; | |
942 | ||
943 | /* | |
944 | * In order to avoid overwritting the superblock on the drive, | |
945 | * btrfs starts at an offset of at least 1MB when doing chunk | |
946 | * allocation. | |
947 | */ | |
948 | skip_space = 1024 * 1024; | |
949 | ||
950 | /* user can set the offset in fs_info->alloc_start. */ | |
951 | if (fs_info->alloc_start + BTRFS_STRIPE_LEN <= | |
952 | device->total_bytes) | |
953 | skip_space = max(fs_info->alloc_start, skip_space); | |
954 | ||
955 | /* | |
956 | * btrfs can not use the free space in [0, skip_space - 1], | |
957 | * we must subtract it from the total. In order to implement | |
958 | * it, we account the used space in this range first. | |
959 | */ | |
960 | ret = btrfs_account_dev_extents_size(device, 0, skip_space - 1, | |
961 | &used_space); | |
962 | if (ret) { | |
963 | kfree(devices_info); | |
964 | return ret; | |
965 | } | |
966 | ||
967 | /* calc the free space in [0, skip_space - 1] */ | |
968 | skip_space -= used_space; | |
969 | ||
970 | /* | |
971 | * we can use the free space in [0, skip_space - 1], subtract | |
972 | * it from the total. | |
973 | */ | |
974 | if (avail_space && avail_space >= skip_space) | |
975 | avail_space -= skip_space; | |
976 | else | |
977 | avail_space = 0; | |
978 | ||
979 | if (avail_space < min_stripe_size) | |
980 | continue; | |
981 | ||
982 | devices_info[i].dev = device; | |
983 | devices_info[i].max_avail = avail_space; | |
984 | ||
985 | i++; | |
986 | } | |
987 | ||
988 | nr_devices = i; | |
989 | ||
990 | btrfs_descending_sort_devices(devices_info, nr_devices); | |
991 | ||
992 | i = nr_devices - 1; | |
993 | avail_space = 0; | |
994 | while (nr_devices >= min_stripes) { | |
995 | if (devices_info[i].max_avail >= min_stripe_size) { | |
996 | int j; | |
997 | u64 alloc_size; | |
998 | ||
999 | avail_space += devices_info[i].max_avail * min_stripes; | |
1000 | alloc_size = devices_info[i].max_avail; | |
1001 | for (j = i + 1 - min_stripes; j <= i; j++) | |
1002 | devices_info[j].max_avail -= alloc_size; | |
1003 | } | |
1004 | i--; | |
1005 | nr_devices--; | |
1006 | } | |
1007 | ||
1008 | kfree(devices_info); | |
1009 | *free_bytes = avail_space; | |
1010 | return 0; | |
1011 | } | |
1012 | ||
8fd17795 CM |
1013 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1014 | { | |
1015 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 1016 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
bd4d1088 JB |
1017 | struct list_head *head = &root->fs_info->space_info; |
1018 | struct btrfs_space_info *found; | |
1019 | u64 total_used = 0; | |
6d07bcec | 1020 | u64 total_free_data = 0; |
db94535d | 1021 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 1022 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
6d07bcec | 1023 | int ret; |
8fd17795 | 1024 | |
6d07bcec MX |
1025 | /* holding chunk_muext to avoid allocating new chunks */ |
1026 | mutex_lock(&root->fs_info->chunk_mutex); | |
bd4d1088 | 1027 | rcu_read_lock(); |
89a55897 | 1028 | list_for_each_entry_rcu(found, head, list) { |
6d07bcec MX |
1029 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) { |
1030 | total_free_data += found->disk_total - found->disk_used; | |
1031 | total_free_data -= | |
1032 | btrfs_account_ro_block_groups_free_space(found); | |
1033 | } | |
1034 | ||
b742bb82 | 1035 | total_used += found->disk_used; |
89a55897 | 1036 | } |
bd4d1088 JB |
1037 | rcu_read_unlock(); |
1038 | ||
8fd17795 | 1039 | buf->f_namelen = BTRFS_NAME_LEN; |
db94535d | 1040 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
bd4d1088 | 1041 | buf->f_bfree = buf->f_blocks - (total_used >> bits); |
8fd17795 CM |
1042 | buf->f_bsize = dentry->d_sb->s_blocksize; |
1043 | buf->f_type = BTRFS_SUPER_MAGIC; | |
6d07bcec MX |
1044 | buf->f_bavail = total_free_data; |
1045 | ret = btrfs_calc_avail_data_space(root, &total_free_data); | |
1046 | if (ret) { | |
1047 | mutex_unlock(&root->fs_info->chunk_mutex); | |
1048 | return ret; | |
1049 | } | |
1050 | buf->f_bavail += total_free_data; | |
1051 | buf->f_bavail = buf->f_bavail >> bits; | |
1052 | mutex_unlock(&root->fs_info->chunk_mutex); | |
d397712b | 1053 | |
9d03632e | 1054 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 1055 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
1056 | on a big-endian or little-endian host */ |
1057 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
1058 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
1059 | /* Mask in the root object ID too, to disambiguate subvols */ |
1060 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
1061 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
1062 | ||
8fd17795 CM |
1063 | return 0; |
1064 | } | |
b5133862 | 1065 | |
2e635a27 CM |
1066 | static struct file_system_type btrfs_fs_type = { |
1067 | .owner = THIS_MODULE, | |
1068 | .name = "btrfs", | |
061dbc6b | 1069 | .mount = btrfs_mount, |
a061fc8d | 1070 | .kill_sb = kill_anon_super, |
2e635a27 CM |
1071 | .fs_flags = FS_REQUIRES_DEV, |
1072 | }; | |
a9218f6b | 1073 | |
d352ac68 CM |
1074 | /* |
1075 | * used by btrfsctl to scan devices when no FS is mounted | |
1076 | */ | |
8a4b83cc CM |
1077 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
1078 | unsigned long arg) | |
1079 | { | |
1080 | struct btrfs_ioctl_vol_args *vol; | |
1081 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 1082 | int ret = -ENOTTY; |
8a4b83cc | 1083 | |
e441d54d CM |
1084 | if (!capable(CAP_SYS_ADMIN)) |
1085 | return -EPERM; | |
1086 | ||
dae7b665 LZ |
1087 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
1088 | if (IS_ERR(vol)) | |
1089 | return PTR_ERR(vol); | |
c071fcfd | 1090 | |
8a4b83cc CM |
1091 | switch (cmd) { |
1092 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 1093 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
1094 | &btrfs_fs_type, &fs_devices); |
1095 | break; | |
1096 | } | |
dae7b665 | 1097 | |
8a4b83cc | 1098 | kfree(vol); |
f819d837 | 1099 | return ret; |
8a4b83cc CM |
1100 | } |
1101 | ||
0176260f | 1102 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
1103 | { |
1104 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
1105 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
1106 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 1107 | return 0; |
ed0dab6b Y |
1108 | } |
1109 | ||
0176260f | 1110 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
1111 | { |
1112 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
1113 | mutex_unlock(&root->fs_info->cleaner_mutex); |
1114 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 1115 | return 0; |
ed0dab6b | 1116 | } |
2e635a27 | 1117 | |
b87221de | 1118 | static const struct super_operations btrfs_super_ops = { |
76dda93c | 1119 | .drop_inode = btrfs_drop_inode, |
bd555975 | 1120 | .evict_inode = btrfs_evict_inode, |
e20d96d6 | 1121 | .put_super = btrfs_put_super, |
d5719762 | 1122 | .sync_fs = btrfs_sync_fs, |
a9572a15 | 1123 | .show_options = btrfs_show_options, |
4730a4bc | 1124 | .write_inode = btrfs_write_inode, |
b5133862 | 1125 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
1126 | .alloc_inode = btrfs_alloc_inode, |
1127 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 1128 | .statfs = btrfs_statfs, |
c146afad | 1129 | .remount_fs = btrfs_remount, |
0176260f LT |
1130 | .freeze_fs = btrfs_freeze, |
1131 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 1132 | }; |
a9218f6b CM |
1133 | |
1134 | static const struct file_operations btrfs_ctl_fops = { | |
1135 | .unlocked_ioctl = btrfs_control_ioctl, | |
1136 | .compat_ioctl = btrfs_control_ioctl, | |
1137 | .owner = THIS_MODULE, | |
6038f373 | 1138 | .llseek = noop_llseek, |
a9218f6b CM |
1139 | }; |
1140 | ||
1141 | static struct miscdevice btrfs_misc = { | |
578454ff | 1142 | .minor = BTRFS_MINOR, |
a9218f6b CM |
1143 | .name = "btrfs-control", |
1144 | .fops = &btrfs_ctl_fops | |
1145 | }; | |
1146 | ||
578454ff KS |
1147 | MODULE_ALIAS_MISCDEV(BTRFS_MINOR); |
1148 | MODULE_ALIAS("devname:btrfs-control"); | |
1149 | ||
a9218f6b CM |
1150 | static int btrfs_interface_init(void) |
1151 | { | |
1152 | return misc_register(&btrfs_misc); | |
1153 | } | |
1154 | ||
b2950863 | 1155 | static void btrfs_interface_exit(void) |
a9218f6b CM |
1156 | { |
1157 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 1158 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
1159 | } |
1160 | ||
2e635a27 CM |
1161 | static int __init init_btrfs_fs(void) |
1162 | { | |
2c90e5d6 | 1163 | int err; |
58176a96 JB |
1164 | |
1165 | err = btrfs_init_sysfs(); | |
1166 | if (err) | |
1167 | return err; | |
1168 | ||
261507a0 | 1169 | err = btrfs_init_compress(); |
2c90e5d6 | 1170 | if (err) |
a74a4b97 | 1171 | goto free_sysfs; |
d1310b2e | 1172 | |
261507a0 LZ |
1173 | err = btrfs_init_cachep(); |
1174 | if (err) | |
1175 | goto free_compress; | |
1176 | ||
d1310b2e | 1177 | err = extent_io_init(); |
2f4cbe64 WB |
1178 | if (err) |
1179 | goto free_cachep; | |
1180 | ||
d1310b2e CM |
1181 | err = extent_map_init(); |
1182 | if (err) | |
1183 | goto free_extent_io; | |
1184 | ||
a9218f6b | 1185 | err = btrfs_interface_init(); |
2f4cbe64 WB |
1186 | if (err) |
1187 | goto free_extent_map; | |
c8b97818 | 1188 | |
a9218f6b CM |
1189 | err = register_filesystem(&btrfs_fs_type); |
1190 | if (err) | |
1191 | goto unregister_ioctl; | |
b3c3da71 CM |
1192 | |
1193 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
1194 | return 0; |
1195 | ||
a9218f6b CM |
1196 | unregister_ioctl: |
1197 | btrfs_interface_exit(); | |
2f4cbe64 WB |
1198 | free_extent_map: |
1199 | extent_map_exit(); | |
d1310b2e CM |
1200 | free_extent_io: |
1201 | extent_io_exit(); | |
2f4cbe64 WB |
1202 | free_cachep: |
1203 | btrfs_destroy_cachep(); | |
261507a0 LZ |
1204 | free_compress: |
1205 | btrfs_exit_compress(); | |
a74a4b97 | 1206 | free_sysfs: |
2f4cbe64 WB |
1207 | btrfs_exit_sysfs(); |
1208 | return err; | |
2e635a27 CM |
1209 | } |
1210 | ||
1211 | static void __exit exit_btrfs_fs(void) | |
1212 | { | |
39279cc3 | 1213 | btrfs_destroy_cachep(); |
a52d9a80 | 1214 | extent_map_exit(); |
d1310b2e | 1215 | extent_io_exit(); |
a9218f6b | 1216 | btrfs_interface_exit(); |
2e635a27 | 1217 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 1218 | btrfs_exit_sysfs(); |
8a4b83cc | 1219 | btrfs_cleanup_fs_uuids(); |
261507a0 | 1220 | btrfs_exit_compress(); |
2e635a27 CM |
1221 | } |
1222 | ||
1223 | module_init(init_btrfs_fs) | |
1224 | module_exit(exit_btrfs_fs) | |
1225 | ||
1226 | MODULE_LICENSE("GPL"); |