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" |
16cdcec7 | 43 | #include "delayed-inode.h" |
2e635a27 | 44 | #include "ctree.h" |
e20d96d6 | 45 | #include "disk-io.h" |
d5719762 | 46 | #include "transaction.h" |
2c90e5d6 | 47 | #include "btrfs_inode.h" |
c5739bba | 48 | #include "ioctl.h" |
3a686375 | 49 | #include "print-tree.h" |
5103e947 | 50 | #include "xattr.h" |
8a4b83cc | 51 | #include "volumes.h" |
b3c3da71 | 52 | #include "version.h" |
be6e8dc0 | 53 | #include "export.h" |
c8b97818 | 54 | #include "compression.h" |
2e635a27 | 55 | |
1abe9b8a | 56 | #define CREATE_TRACE_POINTS |
57 | #include <trace/events/btrfs.h> | |
58 | ||
b87221de | 59 | static const struct super_operations btrfs_super_ops; |
75dfe396 | 60 | |
acce952b | 61 | static const char *btrfs_decode_error(struct btrfs_fs_info *fs_info, int errno, |
62 | char nbuf[16]) | |
63 | { | |
64 | char *errstr = NULL; | |
65 | ||
66 | switch (errno) { | |
67 | case -EIO: | |
68 | errstr = "IO failure"; | |
69 | break; | |
70 | case -ENOMEM: | |
71 | errstr = "Out of memory"; | |
72 | break; | |
73 | case -EROFS: | |
74 | errstr = "Readonly filesystem"; | |
75 | break; | |
76 | default: | |
77 | if (nbuf) { | |
78 | if (snprintf(nbuf, 16, "error %d", -errno) >= 0) | |
79 | errstr = nbuf; | |
80 | } | |
81 | break; | |
82 | } | |
83 | ||
84 | return errstr; | |
85 | } | |
86 | ||
87 | static void __save_error_info(struct btrfs_fs_info *fs_info) | |
88 | { | |
89 | /* | |
90 | * today we only save the error info into ram. Long term we'll | |
91 | * also send it down to the disk | |
92 | */ | |
93 | fs_info->fs_state = BTRFS_SUPER_FLAG_ERROR; | |
94 | } | |
95 | ||
96 | /* NOTE: | |
97 | * We move write_super stuff at umount in order to avoid deadlock | |
98 | * for umount hold all lock. | |
99 | */ | |
100 | static void save_error_info(struct btrfs_fs_info *fs_info) | |
101 | { | |
102 | __save_error_info(fs_info); | |
103 | } | |
104 | ||
105 | /* btrfs handle error by forcing the filesystem readonly */ | |
106 | static void btrfs_handle_error(struct btrfs_fs_info *fs_info) | |
107 | { | |
108 | struct super_block *sb = fs_info->sb; | |
109 | ||
110 | if (sb->s_flags & MS_RDONLY) | |
111 | return; | |
112 | ||
113 | if (fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) { | |
114 | sb->s_flags |= MS_RDONLY; | |
115 | printk(KERN_INFO "btrfs is forced readonly\n"); | |
116 | } | |
117 | } | |
118 | ||
119 | /* | |
120 | * __btrfs_std_error decodes expected errors from the caller and | |
121 | * invokes the approciate error response. | |
122 | */ | |
123 | void __btrfs_std_error(struct btrfs_fs_info *fs_info, const char *function, | |
124 | unsigned int line, int errno) | |
125 | { | |
126 | struct super_block *sb = fs_info->sb; | |
127 | char nbuf[16]; | |
128 | const char *errstr; | |
129 | ||
130 | /* | |
131 | * Special case: if the error is EROFS, and we're already | |
132 | * under MS_RDONLY, then it is safe here. | |
133 | */ | |
134 | if (errno == -EROFS && (sb->s_flags & MS_RDONLY)) | |
135 | return; | |
136 | ||
137 | errstr = btrfs_decode_error(fs_info, errno, nbuf); | |
138 | printk(KERN_CRIT "BTRFS error (device %s) in %s:%d: %s\n", | |
139 | sb->s_id, function, line, errstr); | |
140 | save_error_info(fs_info); | |
141 | ||
142 | btrfs_handle_error(fs_info); | |
143 | } | |
144 | ||
d397712b | 145 | static void btrfs_put_super(struct super_block *sb) |
b18c6685 | 146 | { |
39279cc3 | 147 | struct btrfs_root *root = btrfs_sb(sb); |
b18c6685 | 148 | int ret; |
b18c6685 | 149 | |
39279cc3 | 150 | ret = close_ctree(root); |
39279cc3 | 151 | sb->s_fs_info = NULL; |
559af821 AK |
152 | |
153 | (void)ret; /* FIXME: need to fix VFS to return error? */ | |
75dfe396 CM |
154 | } |
155 | ||
95e05289 | 156 | enum { |
73f73415 | 157 | Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum, |
287a0ab9 JB |
158 | Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, |
159 | Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, | |
261507a0 LZ |
160 | Opt_compress_type, Opt_compress_force, Opt_compress_force_type, |
161 | Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, | |
91435650 | 162 | Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, |
4b9465cb CM |
163 | Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, |
164 | Opt_inode_cache, Opt_err, | |
95e05289 CM |
165 | }; |
166 | ||
167 | static match_table_t tokens = { | |
dfe25020 | 168 | {Opt_degraded, "degraded"}, |
95e05289 | 169 | {Opt_subvol, "subvol=%s"}, |
73f73415 | 170 | {Opt_subvolid, "subvolid=%d"}, |
43e570b0 | 171 | {Opt_device, "device=%s"}, |
b6cda9bc | 172 | {Opt_nodatasum, "nodatasum"}, |
be20aa9d | 173 | {Opt_nodatacow, "nodatacow"}, |
21ad10cf | 174 | {Opt_nobarrier, "nobarrier"}, |
6f568d35 | 175 | {Opt_max_inline, "max_inline=%s"}, |
8f662a76 | 176 | {Opt_alloc_start, "alloc_start=%s"}, |
4543df7e | 177 | {Opt_thread_pool, "thread_pool=%d"}, |
c8b97818 | 178 | {Opt_compress, "compress"}, |
261507a0 | 179 | {Opt_compress_type, "compress=%s"}, |
a555f810 | 180 | {Opt_compress_force, "compress-force"}, |
261507a0 | 181 | {Opt_compress_force_type, "compress-force=%s"}, |
e18e4809 | 182 | {Opt_ssd, "ssd"}, |
451d7585 | 183 | {Opt_ssd_spread, "ssd_spread"}, |
3b30c22f | 184 | {Opt_nossd, "nossd"}, |
33268eaf | 185 | {Opt_noacl, "noacl"}, |
3a5e1404 | 186 | {Opt_notreelog, "notreelog"}, |
dccae999 | 187 | {Opt_flushoncommit, "flushoncommit"}, |
97e728d4 | 188 | {Opt_ratio, "metadata_ratio=%d"}, |
e244a0ae | 189 | {Opt_discard, "discard"}, |
0af3d00b | 190 | {Opt_space_cache, "space_cache"}, |
88c2ba3b | 191 | {Opt_clear_cache, "clear_cache"}, |
4260f7c7 | 192 | {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, |
91435650 | 193 | {Opt_enospc_debug, "enospc_debug"}, |
e15d0542 | 194 | {Opt_subvolrootid, "subvolrootid=%d"}, |
4cb5300b | 195 | {Opt_defrag, "autodefrag"}, |
4b9465cb | 196 | {Opt_inode_cache, "inode_cache"}, |
33268eaf | 197 | {Opt_err, NULL}, |
95e05289 CM |
198 | }; |
199 | ||
edf24abe CH |
200 | /* |
201 | * Regular mount options parser. Everything that is needed only when | |
202 | * reading in a new superblock is parsed here. | |
203 | */ | |
204 | int btrfs_parse_options(struct btrfs_root *root, char *options) | |
95e05289 | 205 | { |
edf24abe | 206 | struct btrfs_fs_info *info = root->fs_info; |
95e05289 | 207 | substring_t args[MAX_OPT_ARGS]; |
da495ecc | 208 | char *p, *num, *orig; |
4543df7e | 209 | int intarg; |
a7a3f7ca | 210 | int ret = 0; |
261507a0 LZ |
211 | char *compress_type; |
212 | bool compress_force = false; | |
b6cda9bc | 213 | |
95e05289 | 214 | if (!options) |
edf24abe | 215 | return 0; |
95e05289 | 216 | |
be20aa9d CM |
217 | /* |
218 | * strsep changes the string, duplicate it because parse_options | |
219 | * gets called twice | |
220 | */ | |
221 | options = kstrdup(options, GFP_NOFS); | |
222 | if (!options) | |
223 | return -ENOMEM; | |
224 | ||
da495ecc | 225 | orig = options; |
be20aa9d | 226 | |
edf24abe | 227 | while ((p = strsep(&options, ",")) != NULL) { |
95e05289 CM |
228 | int token; |
229 | if (!*p) | |
230 | continue; | |
231 | ||
232 | token = match_token(p, tokens, args); | |
233 | switch (token) { | |
dfe25020 | 234 | case Opt_degraded: |
edf24abe CH |
235 | printk(KERN_INFO "btrfs: allowing degraded mounts\n"); |
236 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
dfe25020 | 237 | break; |
95e05289 | 238 | case Opt_subvol: |
73f73415 | 239 | case Opt_subvolid: |
e15d0542 | 240 | case Opt_subvolrootid: |
43e570b0 | 241 | case Opt_device: |
edf24abe | 242 | /* |
43e570b0 | 243 | * These are parsed by btrfs_parse_early_options |
edf24abe CH |
244 | * and can be happily ignored here. |
245 | */ | |
b6cda9bc CM |
246 | break; |
247 | case Opt_nodatasum: | |
067c28ad | 248 | printk(KERN_INFO "btrfs: setting nodatasum\n"); |
edf24abe | 249 | btrfs_set_opt(info->mount_opt, NODATASUM); |
be20aa9d CM |
250 | break; |
251 | case Opt_nodatacow: | |
edf24abe CH |
252 | printk(KERN_INFO "btrfs: setting nodatacow\n"); |
253 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
254 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
95e05289 | 255 | break; |
a555f810 | 256 | case Opt_compress_force: |
261507a0 LZ |
257 | case Opt_compress_force_type: |
258 | compress_force = true; | |
259 | case Opt_compress: | |
260 | case Opt_compress_type: | |
261 | if (token == Opt_compress || | |
262 | token == Opt_compress_force || | |
263 | strcmp(args[0].from, "zlib") == 0) { | |
264 | compress_type = "zlib"; | |
265 | info->compress_type = BTRFS_COMPRESS_ZLIB; | |
a6fa6fae LZ |
266 | } else if (strcmp(args[0].from, "lzo") == 0) { |
267 | compress_type = "lzo"; | |
268 | info->compress_type = BTRFS_COMPRESS_LZO; | |
261507a0 LZ |
269 | } else { |
270 | ret = -EINVAL; | |
271 | goto out; | |
272 | } | |
273 | ||
a555f810 | 274 | btrfs_set_opt(info->mount_opt, COMPRESS); |
261507a0 LZ |
275 | if (compress_force) { |
276 | btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); | |
277 | pr_info("btrfs: force %s compression\n", | |
278 | compress_type); | |
279 | } else | |
280 | pr_info("btrfs: use %s compression\n", | |
281 | compress_type); | |
a555f810 | 282 | break; |
e18e4809 | 283 | case Opt_ssd: |
edf24abe CH |
284 | printk(KERN_INFO "btrfs: use ssd allocation scheme\n"); |
285 | btrfs_set_opt(info->mount_opt, SSD); | |
e18e4809 | 286 | break; |
451d7585 CM |
287 | case Opt_ssd_spread: |
288 | printk(KERN_INFO "btrfs: use spread ssd " | |
289 | "allocation scheme\n"); | |
290 | btrfs_set_opt(info->mount_opt, SSD); | |
291 | btrfs_set_opt(info->mount_opt, SSD_SPREAD); | |
292 | break; | |
3b30c22f | 293 | case Opt_nossd: |
451d7585 CM |
294 | printk(KERN_INFO "btrfs: not using ssd allocation " |
295 | "scheme\n"); | |
c289811c | 296 | btrfs_set_opt(info->mount_opt, NOSSD); |
3b30c22f | 297 | btrfs_clear_opt(info->mount_opt, SSD); |
451d7585 | 298 | btrfs_clear_opt(info->mount_opt, SSD_SPREAD); |
3b30c22f | 299 | break; |
21ad10cf | 300 | case Opt_nobarrier: |
edf24abe CH |
301 | printk(KERN_INFO "btrfs: turning off barriers\n"); |
302 | btrfs_set_opt(info->mount_opt, NOBARRIER); | |
21ad10cf | 303 | break; |
4543df7e CM |
304 | case Opt_thread_pool: |
305 | intarg = 0; | |
306 | match_int(&args[0], &intarg); | |
307 | if (intarg) { | |
308 | info->thread_pool_size = intarg; | |
309 | printk(KERN_INFO "btrfs: thread pool %d\n", | |
310 | info->thread_pool_size); | |
311 | } | |
312 | break; | |
6f568d35 | 313 | case Opt_max_inline: |
edf24abe CH |
314 | num = match_strdup(&args[0]); |
315 | if (num) { | |
91748467 | 316 | info->max_inline = memparse(num, NULL); |
edf24abe CH |
317 | kfree(num); |
318 | ||
15ada040 CM |
319 | if (info->max_inline) { |
320 | info->max_inline = max_t(u64, | |
321 | info->max_inline, | |
322 | root->sectorsize); | |
323 | } | |
edf24abe | 324 | printk(KERN_INFO "btrfs: max_inline at %llu\n", |
21380931 | 325 | (unsigned long long)info->max_inline); |
6f568d35 CM |
326 | } |
327 | break; | |
8f662a76 | 328 | case Opt_alloc_start: |
edf24abe CH |
329 | num = match_strdup(&args[0]); |
330 | if (num) { | |
91748467 | 331 | info->alloc_start = memparse(num, NULL); |
edf24abe CH |
332 | kfree(num); |
333 | printk(KERN_INFO | |
334 | "btrfs: allocations start at %llu\n", | |
21380931 | 335 | (unsigned long long)info->alloc_start); |
8f662a76 CM |
336 | } |
337 | break; | |
33268eaf JB |
338 | case Opt_noacl: |
339 | root->fs_info->sb->s_flags &= ~MS_POSIXACL; | |
340 | break; | |
3a5e1404 SW |
341 | case Opt_notreelog: |
342 | printk(KERN_INFO "btrfs: disabling tree log\n"); | |
343 | btrfs_set_opt(info->mount_opt, NOTREELOG); | |
344 | break; | |
dccae999 SW |
345 | case Opt_flushoncommit: |
346 | printk(KERN_INFO "btrfs: turning on flush-on-commit\n"); | |
347 | btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT); | |
348 | break; | |
97e728d4 JB |
349 | case Opt_ratio: |
350 | intarg = 0; | |
351 | match_int(&args[0], &intarg); | |
352 | if (intarg) { | |
353 | info->metadata_ratio = intarg; | |
354 | printk(KERN_INFO "btrfs: metadata ratio %d\n", | |
355 | info->metadata_ratio); | |
356 | } | |
357 | break; | |
e244a0ae CH |
358 | case Opt_discard: |
359 | btrfs_set_opt(info->mount_opt, DISCARD); | |
360 | break; | |
0af3d00b JB |
361 | case Opt_space_cache: |
362 | printk(KERN_INFO "btrfs: enabling disk space caching\n"); | |
363 | btrfs_set_opt(info->mount_opt, SPACE_CACHE); | |
0de90876 | 364 | break; |
4b9465cb CM |
365 | case Opt_inode_cache: |
366 | printk(KERN_INFO "btrfs: enabling inode map caching\n"); | |
367 | btrfs_set_opt(info->mount_opt, INODE_MAP_CACHE); | |
368 | break; | |
88c2ba3b JB |
369 | case Opt_clear_cache: |
370 | printk(KERN_INFO "btrfs: force clearing of disk cache\n"); | |
371 | btrfs_set_opt(info->mount_opt, CLEAR_CACHE); | |
0af3d00b | 372 | break; |
4260f7c7 SW |
373 | case Opt_user_subvol_rm_allowed: |
374 | btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); | |
375 | break; | |
91435650 CM |
376 | case Opt_enospc_debug: |
377 | btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); | |
378 | break; | |
4cb5300b CM |
379 | case Opt_defrag: |
380 | printk(KERN_INFO "btrfs: enabling auto defrag"); | |
381 | btrfs_set_opt(info->mount_opt, AUTO_DEFRAG); | |
382 | break; | |
a7a3f7ca SW |
383 | case Opt_err: |
384 | printk(KERN_INFO "btrfs: unrecognized mount option " | |
385 | "'%s'\n", p); | |
386 | ret = -EINVAL; | |
387 | goto out; | |
95e05289 | 388 | default: |
be20aa9d | 389 | break; |
95e05289 CM |
390 | } |
391 | } | |
a7a3f7ca | 392 | out: |
da495ecc | 393 | kfree(orig); |
a7a3f7ca | 394 | return ret; |
edf24abe CH |
395 | } |
396 | ||
397 | /* | |
398 | * Parse mount options that are required early in the mount process. | |
399 | * | |
400 | * All other options will be parsed on much later in the mount process and | |
401 | * only when we need to allocate a new super block. | |
402 | */ | |
97288f2c | 403 | static int btrfs_parse_early_options(const char *options, fmode_t flags, |
73f73415 | 404 | void *holder, char **subvol_name, u64 *subvol_objectid, |
e15d0542 | 405 | u64 *subvol_rootid, struct btrfs_fs_devices **fs_devices) |
edf24abe CH |
406 | { |
407 | substring_t args[MAX_OPT_ARGS]; | |
3f3d0bc0 | 408 | char *opts, *orig, *p; |
edf24abe | 409 | int error = 0; |
73f73415 | 410 | int intarg; |
edf24abe CH |
411 | |
412 | if (!options) | |
413 | goto out; | |
414 | ||
415 | /* | |
416 | * strsep changes the string, duplicate it because parse_options | |
417 | * gets called twice | |
418 | */ | |
419 | opts = kstrdup(options, GFP_KERNEL); | |
420 | if (!opts) | |
421 | return -ENOMEM; | |
3f3d0bc0 | 422 | orig = opts; |
edf24abe CH |
423 | |
424 | while ((p = strsep(&opts, ",")) != NULL) { | |
425 | int token; | |
426 | if (!*p) | |
427 | continue; | |
428 | ||
429 | token = match_token(p, tokens, args); | |
430 | switch (token) { | |
431 | case Opt_subvol: | |
432 | *subvol_name = match_strdup(&args[0]); | |
433 | break; | |
73f73415 JB |
434 | case Opt_subvolid: |
435 | intarg = 0; | |
4849f01d JB |
436 | error = match_int(&args[0], &intarg); |
437 | if (!error) { | |
438 | /* we want the original fs_tree */ | |
439 | if (!intarg) | |
440 | *subvol_objectid = | |
441 | BTRFS_FS_TREE_OBJECTID; | |
442 | else | |
443 | *subvol_objectid = intarg; | |
444 | } | |
73f73415 | 445 | break; |
e15d0542 XZ |
446 | case Opt_subvolrootid: |
447 | intarg = 0; | |
448 | error = match_int(&args[0], &intarg); | |
449 | if (!error) { | |
450 | /* we want the original fs_tree */ | |
451 | if (!intarg) | |
452 | *subvol_rootid = | |
453 | BTRFS_FS_TREE_OBJECTID; | |
454 | else | |
455 | *subvol_rootid = intarg; | |
456 | } | |
457 | break; | |
43e570b0 CH |
458 | case Opt_device: |
459 | error = btrfs_scan_one_device(match_strdup(&args[0]), | |
460 | flags, holder, fs_devices); | |
461 | if (error) | |
462 | goto out_free_opts; | |
463 | break; | |
edf24abe CH |
464 | default: |
465 | break; | |
466 | } | |
467 | } | |
468 | ||
43e570b0 | 469 | out_free_opts: |
3f3d0bc0 | 470 | kfree(orig); |
edf24abe CH |
471 | out: |
472 | /* | |
473 | * If no subvolume name is specified we use the default one. Allocate | |
3de4586c | 474 | * a copy of the string "." here so that code later in the |
edf24abe CH |
475 | * mount path doesn't care if it's the default volume or another one. |
476 | */ | |
477 | if (!*subvol_name) { | |
3de4586c | 478 | *subvol_name = kstrdup(".", GFP_KERNEL); |
edf24abe CH |
479 | if (!*subvol_name) |
480 | return -ENOMEM; | |
481 | } | |
482 | return error; | |
95e05289 CM |
483 | } |
484 | ||
73f73415 JB |
485 | static struct dentry *get_default_root(struct super_block *sb, |
486 | u64 subvol_objectid) | |
487 | { | |
488 | struct btrfs_root *root = sb->s_fs_info; | |
489 | struct btrfs_root *new_root; | |
490 | struct btrfs_dir_item *di; | |
491 | struct btrfs_path *path; | |
492 | struct btrfs_key location; | |
493 | struct inode *inode; | |
494 | struct dentry *dentry; | |
495 | u64 dir_id; | |
496 | int new = 0; | |
497 | ||
498 | /* | |
499 | * We have a specific subvol we want to mount, just setup location and | |
500 | * go look up the root. | |
501 | */ | |
502 | if (subvol_objectid) { | |
503 | location.objectid = subvol_objectid; | |
504 | location.type = BTRFS_ROOT_ITEM_KEY; | |
505 | location.offset = (u64)-1; | |
506 | goto find_root; | |
507 | } | |
508 | ||
509 | path = btrfs_alloc_path(); | |
510 | if (!path) | |
511 | return ERR_PTR(-ENOMEM); | |
512 | path->leave_spinning = 1; | |
513 | ||
514 | /* | |
515 | * Find the "default" dir item which points to the root item that we | |
516 | * will mount by default if we haven't been given a specific subvolume | |
517 | * to mount. | |
518 | */ | |
519 | dir_id = btrfs_super_root_dir(&root->fs_info->super_copy); | |
520 | di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); | |
b0839166 JL |
521 | if (IS_ERR(di)) { |
522 | btrfs_free_path(path); | |
fb4f6f91 | 523 | return ERR_CAST(di); |
b0839166 | 524 | } |
73f73415 JB |
525 | if (!di) { |
526 | /* | |
527 | * Ok the default dir item isn't there. This is weird since | |
528 | * it's always been there, but don't freak out, just try and | |
529 | * mount to root most subvolume. | |
530 | */ | |
531 | btrfs_free_path(path); | |
532 | dir_id = BTRFS_FIRST_FREE_OBJECTID; | |
533 | new_root = root->fs_info->fs_root; | |
534 | goto setup_root; | |
535 | } | |
536 | ||
537 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); | |
538 | btrfs_free_path(path); | |
539 | ||
540 | find_root: | |
541 | new_root = btrfs_read_fs_root_no_name(root->fs_info, &location); | |
542 | if (IS_ERR(new_root)) | |
d0b678cb | 543 | return ERR_CAST(new_root); |
73f73415 JB |
544 | |
545 | if (btrfs_root_refs(&new_root->root_item) == 0) | |
546 | return ERR_PTR(-ENOENT); | |
547 | ||
548 | dir_id = btrfs_root_dirid(&new_root->root_item); | |
549 | setup_root: | |
550 | location.objectid = dir_id; | |
551 | location.type = BTRFS_INODE_ITEM_KEY; | |
552 | location.offset = 0; | |
553 | ||
554 | inode = btrfs_iget(sb, &location, new_root, &new); | |
4cbd1149 DC |
555 | if (IS_ERR(inode)) |
556 | return ERR_CAST(inode); | |
73f73415 JB |
557 | |
558 | /* | |
559 | * If we're just mounting the root most subvol put the inode and return | |
560 | * a reference to the dentry. We will have already gotten a reference | |
561 | * to the inode in btrfs_fill_super so we're good to go. | |
562 | */ | |
563 | if (!new && sb->s_root->d_inode == inode) { | |
564 | iput(inode); | |
565 | return dget(sb->s_root); | |
566 | } | |
567 | ||
568 | if (new) { | |
569 | const struct qstr name = { .name = "/", .len = 1 }; | |
570 | ||
571 | /* | |
572 | * New inode, we need to make the dentry a sibling of s_root so | |
573 | * everything gets cleaned up properly on unmount. | |
574 | */ | |
575 | dentry = d_alloc(sb->s_root, &name); | |
576 | if (!dentry) { | |
577 | iput(inode); | |
578 | return ERR_PTR(-ENOMEM); | |
579 | } | |
580 | d_splice_alias(inode, dentry); | |
581 | } else { | |
582 | /* | |
583 | * We found the inode in cache, just find a dentry for it and | |
584 | * put the reference to the inode we just got. | |
585 | */ | |
586 | dentry = d_find_alias(inode); | |
587 | iput(inode); | |
588 | } | |
589 | ||
590 | return dentry; | |
591 | } | |
592 | ||
d397712b | 593 | static int btrfs_fill_super(struct super_block *sb, |
8a4b83cc | 594 | struct btrfs_fs_devices *fs_devices, |
d397712b | 595 | void *data, int silent) |
75dfe396 | 596 | { |
d397712b CM |
597 | struct inode *inode; |
598 | struct dentry *root_dentry; | |
39279cc3 | 599 | struct btrfs_root *tree_root; |
5d4f98a2 | 600 | struct btrfs_key key; |
39279cc3 | 601 | int err; |
a429e513 | 602 | |
39279cc3 CM |
603 | sb->s_maxbytes = MAX_LFS_FILESIZE; |
604 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
605 | sb->s_op = &btrfs_super_ops; | |
af53d29a | 606 | sb->s_d_op = &btrfs_dentry_operations; |
be6e8dc0 | 607 | sb->s_export_op = &btrfs_export_ops; |
5103e947 | 608 | sb->s_xattr = btrfs_xattr_handlers; |
39279cc3 | 609 | sb->s_time_gran = 1; |
0eda294d | 610 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL |
33268eaf | 611 | sb->s_flags |= MS_POSIXACL; |
49cf6f45 | 612 | #endif |
a429e513 | 613 | |
dfe25020 | 614 | tree_root = open_ctree(sb, fs_devices, (char *)data); |
6567e837 | 615 | |
e58ca020 | 616 | if (IS_ERR(tree_root)) { |
39279cc3 | 617 | printk("btrfs: open_ctree failed\n"); |
e58ca020 | 618 | return PTR_ERR(tree_root); |
a429e513 | 619 | } |
39279cc3 | 620 | sb->s_fs_info = tree_root; |
a429e513 | 621 | |
5d4f98a2 YZ |
622 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; |
623 | key.type = BTRFS_INODE_ITEM_KEY; | |
624 | key.offset = 0; | |
73f73415 | 625 | inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root, NULL); |
5d4f98a2 YZ |
626 | if (IS_ERR(inode)) { |
627 | err = PTR_ERR(inode); | |
39279cc3 | 628 | goto fail_close; |
f254e52c | 629 | } |
f254e52c | 630 | |
39279cc3 CM |
631 | root_dentry = d_alloc_root(inode); |
632 | if (!root_dentry) { | |
633 | iput(inode); | |
634 | err = -ENOMEM; | |
635 | goto fail_close; | |
f254e52c | 636 | } |
58176a96 | 637 | |
39279cc3 | 638 | sb->s_root = root_dentry; |
6885f308 | 639 | |
6885f308 | 640 | save_mount_options(sb, data); |
2619ba1f | 641 | return 0; |
39279cc3 CM |
642 | |
643 | fail_close: | |
644 | close_ctree(tree_root); | |
645 | return err; | |
2619ba1f CM |
646 | } |
647 | ||
6bf13c0c | 648 | int btrfs_sync_fs(struct super_block *sb, int wait) |
c5739bba CM |
649 | { |
650 | struct btrfs_trans_handle *trans; | |
dccae999 | 651 | struct btrfs_root *root = btrfs_sb(sb); |
c5739bba | 652 | int ret; |
2619ba1f | 653 | |
1abe9b8a | 654 | trace_btrfs_sync_fs(wait); |
655 | ||
39279cc3 CM |
656 | if (!wait) { |
657 | filemap_flush(root->fs_info->btree_inode->i_mapping); | |
658 | return 0; | |
659 | } | |
771ed689 | 660 | |
24bbcf04 YZ |
661 | btrfs_start_delalloc_inodes(root, 0); |
662 | btrfs_wait_ordered_extents(root, 0, 0); | |
771ed689 | 663 | |
a22285a6 | 664 | trans = btrfs_start_transaction(root, 0); |
98d5dc13 TI |
665 | if (IS_ERR(trans)) |
666 | return PTR_ERR(trans); | |
c5739bba | 667 | ret = btrfs_commit_transaction(trans, root); |
54aa1f4d | 668 | return ret; |
2c90e5d6 CM |
669 | } |
670 | ||
a9572a15 EP |
671 | static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs) |
672 | { | |
673 | struct btrfs_root *root = btrfs_sb(vfs->mnt_sb); | |
674 | struct btrfs_fs_info *info = root->fs_info; | |
200da64e | 675 | char *compress_type; |
a9572a15 EP |
676 | |
677 | if (btrfs_test_opt(root, DEGRADED)) | |
678 | seq_puts(seq, ",degraded"); | |
679 | if (btrfs_test_opt(root, NODATASUM)) | |
680 | seq_puts(seq, ",nodatasum"); | |
681 | if (btrfs_test_opt(root, NODATACOW)) | |
682 | seq_puts(seq, ",nodatacow"); | |
683 | if (btrfs_test_opt(root, NOBARRIER)) | |
684 | seq_puts(seq, ",nobarrier"); | |
a9572a15 | 685 | if (info->max_inline != 8192 * 1024) |
21380931 JB |
686 | seq_printf(seq, ",max_inline=%llu", |
687 | (unsigned long long)info->max_inline); | |
a9572a15 | 688 | if (info->alloc_start != 0) |
21380931 JB |
689 | seq_printf(seq, ",alloc_start=%llu", |
690 | (unsigned long long)info->alloc_start); | |
a9572a15 EP |
691 | if (info->thread_pool_size != min_t(unsigned long, |
692 | num_online_cpus() + 2, 8)) | |
693 | seq_printf(seq, ",thread_pool=%d", info->thread_pool_size); | |
200da64e TI |
694 | if (btrfs_test_opt(root, COMPRESS)) { |
695 | if (info->compress_type == BTRFS_COMPRESS_ZLIB) | |
696 | compress_type = "zlib"; | |
697 | else | |
698 | compress_type = "lzo"; | |
699 | if (btrfs_test_opt(root, FORCE_COMPRESS)) | |
700 | seq_printf(seq, ",compress-force=%s", compress_type); | |
701 | else | |
702 | seq_printf(seq, ",compress=%s", compress_type); | |
703 | } | |
c289811c CM |
704 | if (btrfs_test_opt(root, NOSSD)) |
705 | seq_puts(seq, ",nossd"); | |
451d7585 CM |
706 | if (btrfs_test_opt(root, SSD_SPREAD)) |
707 | seq_puts(seq, ",ssd_spread"); | |
708 | else if (btrfs_test_opt(root, SSD)) | |
a9572a15 | 709 | seq_puts(seq, ",ssd"); |
3a5e1404 | 710 | if (btrfs_test_opt(root, NOTREELOG)) |
6b65c5c6 | 711 | seq_puts(seq, ",notreelog"); |
dccae999 | 712 | if (btrfs_test_opt(root, FLUSHONCOMMIT)) |
6b65c5c6 | 713 | seq_puts(seq, ",flushoncommit"); |
20a5239a MW |
714 | if (btrfs_test_opt(root, DISCARD)) |
715 | seq_puts(seq, ",discard"); | |
a9572a15 EP |
716 | if (!(root->fs_info->sb->s_flags & MS_POSIXACL)) |
717 | seq_puts(seq, ",noacl"); | |
200da64e TI |
718 | if (btrfs_test_opt(root, SPACE_CACHE)) |
719 | seq_puts(seq, ",space_cache"); | |
720 | if (btrfs_test_opt(root, CLEAR_CACHE)) | |
721 | seq_puts(seq, ",clear_cache"); | |
722 | if (btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED)) | |
723 | seq_puts(seq, ",user_subvol_rm_allowed"); | |
0942caa3 DS |
724 | if (btrfs_test_opt(root, ENOSPC_DEBUG)) |
725 | seq_puts(seq, ",enospc_debug"); | |
726 | if (btrfs_test_opt(root, AUTO_DEFRAG)) | |
727 | seq_puts(seq, ",autodefrag"); | |
728 | if (btrfs_test_opt(root, INODE_MAP_CACHE)) | |
729 | seq_puts(seq, ",inode_cache"); | |
a9572a15 EP |
730 | return 0; |
731 | } | |
732 | ||
a061fc8d | 733 | static int btrfs_test_super(struct super_block *s, void *data) |
4b82d6e4 | 734 | { |
450ba0ea | 735 | struct btrfs_root *test_root = data; |
a061fc8d | 736 | struct btrfs_root *root = btrfs_sb(s); |
4b82d6e4 | 737 | |
619c8c76 IK |
738 | /* |
739 | * If this super block is going away, return false as it | |
740 | * can't match as an existing super block. | |
741 | */ | |
742 | if (!atomic_read(&s->s_active)) | |
743 | return 0; | |
450ba0ea | 744 | return root->fs_info->fs_devices == test_root->fs_info->fs_devices; |
4b82d6e4 Y |
745 | } |
746 | ||
450ba0ea JB |
747 | static int btrfs_set_super(struct super_block *s, void *data) |
748 | { | |
749 | s->s_fs_info = data; | |
750 | ||
751 | return set_anon_super(s, data); | |
4b82d6e4 Y |
752 | } |
753 | ||
450ba0ea | 754 | |
edf24abe CH |
755 | /* |
756 | * Find a superblock for the given device / mount point. | |
757 | * | |
758 | * Note: This is based on get_sb_bdev from fs/super.c with a few additions | |
759 | * for multiple device setup. Make sure to keep it in sync. | |
760 | */ | |
061dbc6b | 761 | static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, |
306e16ce | 762 | const char *device_name, void *data) |
4b82d6e4 Y |
763 | { |
764 | struct block_device *bdev = NULL; | |
765 | struct super_block *s; | |
766 | struct dentry *root; | |
8a4b83cc | 767 | struct btrfs_fs_devices *fs_devices = NULL; |
450ba0ea JB |
768 | struct btrfs_root *tree_root = NULL; |
769 | struct btrfs_fs_info *fs_info = NULL; | |
97288f2c | 770 | fmode_t mode = FMODE_READ; |
73f73415 JB |
771 | char *subvol_name = NULL; |
772 | u64 subvol_objectid = 0; | |
e15d0542 | 773 | u64 subvol_rootid = 0; |
4b82d6e4 Y |
774 | int error = 0; |
775 | ||
97288f2c CH |
776 | if (!(flags & MS_RDONLY)) |
777 | mode |= FMODE_WRITE; | |
778 | ||
779 | error = btrfs_parse_early_options(data, mode, fs_type, | |
73f73415 | 780 | &subvol_name, &subvol_objectid, |
e15d0542 | 781 | &subvol_rootid, &fs_devices); |
edf24abe | 782 | if (error) |
061dbc6b | 783 | return ERR_PTR(error); |
edf24abe | 784 | |
306e16ce | 785 | error = btrfs_scan_one_device(device_name, mode, fs_type, &fs_devices); |
8a4b83cc | 786 | if (error) |
edf24abe | 787 | goto error_free_subvol_name; |
4b82d6e4 | 788 | |
97288f2c | 789 | error = btrfs_open_devices(fs_devices, mode, fs_type); |
8a4b83cc | 790 | if (error) |
edf24abe | 791 | goto error_free_subvol_name; |
8a4b83cc | 792 | |
2b82032c YZ |
793 | if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) { |
794 | error = -EACCES; | |
795 | goto error_close_devices; | |
796 | } | |
797 | ||
450ba0ea JB |
798 | /* |
799 | * Setup a dummy root and fs_info for test/set super. This is because | |
800 | * we don't actually fill this stuff out until open_ctree, but we need | |
801 | * it for searching for existing supers, so this lets us do that and | |
802 | * then open_ctree will properly initialize everything later. | |
803 | */ | |
804 | fs_info = kzalloc(sizeof(struct btrfs_fs_info), GFP_NOFS); | |
805 | tree_root = kzalloc(sizeof(struct btrfs_root), GFP_NOFS); | |
806 | if (!fs_info || !tree_root) { | |
807 | error = -ENOMEM; | |
808 | goto error_close_devices; | |
809 | } | |
810 | fs_info->tree_root = tree_root; | |
811 | fs_info->fs_devices = fs_devices; | |
812 | tree_root->fs_info = fs_info; | |
813 | ||
dfe25020 | 814 | bdev = fs_devices->latest_bdev; |
450ba0ea | 815 | s = sget(fs_type, btrfs_test_super, btrfs_set_super, tree_root); |
4b82d6e4 Y |
816 | if (IS_ERR(s)) |
817 | goto error_s; | |
818 | ||
819 | if (s->s_root) { | |
820 | if ((flags ^ s->s_flags) & MS_RDONLY) { | |
6f5bbff9 | 821 | deactivate_locked_super(s); |
4b82d6e4 | 822 | error = -EBUSY; |
c146afad | 823 | goto error_close_devices; |
4b82d6e4 Y |
824 | } |
825 | ||
2b82032c | 826 | btrfs_close_devices(fs_devices); |
bdc924bb IK |
827 | kfree(fs_info); |
828 | kfree(tree_root); | |
4b82d6e4 Y |
829 | } else { |
830 | char b[BDEVNAME_SIZE]; | |
831 | ||
832 | s->s_flags = flags; | |
833 | strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); | |
8a4b83cc CM |
834 | error = btrfs_fill_super(s, fs_devices, data, |
835 | flags & MS_SILENT ? 1 : 0); | |
4b82d6e4 | 836 | if (error) { |
6f5bbff9 | 837 | deactivate_locked_super(s); |
1f483660 | 838 | goto error_free_subvol_name; |
4b82d6e4 Y |
839 | } |
840 | ||
788f20eb | 841 | btrfs_sb(s)->fs_info->bdev_holder = fs_type; |
4b82d6e4 Y |
842 | s->s_flags |= MS_ACTIVE; |
843 | } | |
844 | ||
73f73415 JB |
845 | /* if they gave us a subvolume name bind mount into that */ |
846 | if (strcmp(subvol_name, ".")) { | |
847 | struct dentry *new_root; | |
e15d0542 XZ |
848 | |
849 | root = get_default_root(s, subvol_rootid); | |
850 | if (IS_ERR(root)) { | |
851 | error = PTR_ERR(root); | |
852 | deactivate_locked_super(s); | |
853 | goto error_free_subvol_name; | |
854 | } | |
855 | ||
73f73415 JB |
856 | mutex_lock(&root->d_inode->i_mutex); |
857 | new_root = lookup_one_len(subvol_name, root, | |
d397712b | 858 | strlen(subvol_name)); |
73f73415 | 859 | mutex_unlock(&root->d_inode->i_mutex); |
d397712b | 860 | |
73f73415 | 861 | if (IS_ERR(new_root)) { |
f106e82c | 862 | dput(root); |
6f5bbff9 | 863 | deactivate_locked_super(s); |
73f73415 | 864 | error = PTR_ERR(new_root); |
0e78340f | 865 | goto error_free_subvol_name; |
76fcef19 | 866 | } |
73f73415 | 867 | if (!new_root->d_inode) { |
76fcef19 | 868 | dput(root); |
73f73415 | 869 | dput(new_root); |
6f5bbff9 | 870 | deactivate_locked_super(s); |
76fcef19 | 871 | error = -ENXIO; |
0e78340f | 872 | goto error_free_subvol_name; |
76fcef19 | 873 | } |
73f73415 JB |
874 | dput(root); |
875 | root = new_root; | |
e15d0542 XZ |
876 | } else { |
877 | root = get_default_root(s, subvol_objectid); | |
878 | if (IS_ERR(root)) { | |
879 | error = PTR_ERR(root); | |
880 | deactivate_locked_super(s); | |
881 | goto error_free_subvol_name; | |
882 | } | |
4b82d6e4 Y |
883 | } |
884 | ||
edf24abe | 885 | kfree(subvol_name); |
061dbc6b | 886 | return root; |
4b82d6e4 Y |
887 | |
888 | error_s: | |
889 | error = PTR_ERR(s); | |
c146afad | 890 | error_close_devices: |
8a4b83cc | 891 | btrfs_close_devices(fs_devices); |
450ba0ea JB |
892 | kfree(fs_info); |
893 | kfree(tree_root); | |
edf24abe CH |
894 | error_free_subvol_name: |
895 | kfree(subvol_name); | |
061dbc6b | 896 | return ERR_PTR(error); |
4b82d6e4 | 897 | } |
2e635a27 | 898 | |
c146afad YZ |
899 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) |
900 | { | |
901 | struct btrfs_root *root = btrfs_sb(sb); | |
902 | int ret; | |
903 | ||
b288052e CM |
904 | ret = btrfs_parse_options(root, data); |
905 | if (ret) | |
906 | return -EINVAL; | |
907 | ||
c146afad YZ |
908 | if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) |
909 | return 0; | |
910 | ||
911 | if (*flags & MS_RDONLY) { | |
912 | sb->s_flags |= MS_RDONLY; | |
913 | ||
914 | ret = btrfs_commit_super(root); | |
915 | WARN_ON(ret); | |
916 | } else { | |
2b82032c YZ |
917 | if (root->fs_info->fs_devices->rw_devices == 0) |
918 | return -EACCES; | |
919 | ||
c146afad YZ |
920 | if (btrfs_super_log_root(&root->fs_info->super_copy) != 0) |
921 | return -EINVAL; | |
922 | ||
d68fc57b | 923 | ret = btrfs_cleanup_fs_roots(root->fs_info); |
c146afad YZ |
924 | WARN_ON(ret); |
925 | ||
d68fc57b YZ |
926 | /* recover relocation */ |
927 | ret = btrfs_recover_relocation(root); | |
c146afad YZ |
928 | WARN_ON(ret); |
929 | ||
930 | sb->s_flags &= ~MS_RDONLY; | |
931 | } | |
932 | ||
933 | return 0; | |
934 | } | |
935 | ||
bcd53741 AJ |
936 | /* Used to sort the devices by max_avail(descending sort) */ |
937 | static int btrfs_cmp_device_free_bytes(const void *dev_info1, | |
938 | const void *dev_info2) | |
939 | { | |
940 | if (((struct btrfs_device_info *)dev_info1)->max_avail > | |
941 | ((struct btrfs_device_info *)dev_info2)->max_avail) | |
942 | return -1; | |
943 | else if (((struct btrfs_device_info *)dev_info1)->max_avail < | |
944 | ((struct btrfs_device_info *)dev_info2)->max_avail) | |
945 | return 1; | |
946 | else | |
947 | return 0; | |
948 | } | |
949 | ||
950 | /* | |
951 | * sort the devices by max_avail, in which max free extent size of each device | |
952 | * is stored.(Descending Sort) | |
953 | */ | |
954 | static inline void btrfs_descending_sort_devices( | |
955 | struct btrfs_device_info *devices, | |
956 | size_t nr_devices) | |
957 | { | |
958 | sort(devices, nr_devices, sizeof(struct btrfs_device_info), | |
959 | btrfs_cmp_device_free_bytes, NULL); | |
960 | } | |
961 | ||
6d07bcec MX |
962 | /* |
963 | * The helper to calc the free space on the devices that can be used to store | |
964 | * file data. | |
965 | */ | |
966 | static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes) | |
967 | { | |
968 | struct btrfs_fs_info *fs_info = root->fs_info; | |
969 | struct btrfs_device_info *devices_info; | |
970 | struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; | |
971 | struct btrfs_device *device; | |
972 | u64 skip_space; | |
973 | u64 type; | |
974 | u64 avail_space; | |
975 | u64 used_space; | |
976 | u64 min_stripe_size; | |
977 | int min_stripes = 1; | |
978 | int i = 0, nr_devices; | |
979 | int ret; | |
980 | ||
981 | nr_devices = fs_info->fs_devices->rw_devices; | |
982 | BUG_ON(!nr_devices); | |
983 | ||
984 | devices_info = kmalloc(sizeof(*devices_info) * nr_devices, | |
985 | GFP_NOFS); | |
986 | if (!devices_info) | |
987 | return -ENOMEM; | |
988 | ||
989 | /* calc min stripe number for data space alloction */ | |
990 | type = btrfs_get_alloc_profile(root, 1); | |
991 | if (type & BTRFS_BLOCK_GROUP_RAID0) | |
992 | min_stripes = 2; | |
993 | else if (type & BTRFS_BLOCK_GROUP_RAID1) | |
994 | min_stripes = 2; | |
995 | else if (type & BTRFS_BLOCK_GROUP_RAID10) | |
996 | min_stripes = 4; | |
997 | ||
998 | if (type & BTRFS_BLOCK_GROUP_DUP) | |
999 | min_stripe_size = 2 * BTRFS_STRIPE_LEN; | |
1000 | else | |
1001 | min_stripe_size = BTRFS_STRIPE_LEN; | |
1002 | ||
1003 | list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) { | |
1004 | if (!device->in_fs_metadata) | |
1005 | continue; | |
1006 | ||
1007 | avail_space = device->total_bytes - device->bytes_used; | |
1008 | ||
1009 | /* align with stripe_len */ | |
1010 | do_div(avail_space, BTRFS_STRIPE_LEN); | |
1011 | avail_space *= BTRFS_STRIPE_LEN; | |
1012 | ||
1013 | /* | |
1014 | * In order to avoid overwritting the superblock on the drive, | |
1015 | * btrfs starts at an offset of at least 1MB when doing chunk | |
1016 | * allocation. | |
1017 | */ | |
1018 | skip_space = 1024 * 1024; | |
1019 | ||
1020 | /* user can set the offset in fs_info->alloc_start. */ | |
1021 | if (fs_info->alloc_start + BTRFS_STRIPE_LEN <= | |
1022 | device->total_bytes) | |
1023 | skip_space = max(fs_info->alloc_start, skip_space); | |
1024 | ||
1025 | /* | |
1026 | * btrfs can not use the free space in [0, skip_space - 1], | |
1027 | * we must subtract it from the total. In order to implement | |
1028 | * it, we account the used space in this range first. | |
1029 | */ | |
1030 | ret = btrfs_account_dev_extents_size(device, 0, skip_space - 1, | |
1031 | &used_space); | |
1032 | if (ret) { | |
1033 | kfree(devices_info); | |
1034 | return ret; | |
1035 | } | |
1036 | ||
1037 | /* calc the free space in [0, skip_space - 1] */ | |
1038 | skip_space -= used_space; | |
1039 | ||
1040 | /* | |
1041 | * we can use the free space in [0, skip_space - 1], subtract | |
1042 | * it from the total. | |
1043 | */ | |
1044 | if (avail_space && avail_space >= skip_space) | |
1045 | avail_space -= skip_space; | |
1046 | else | |
1047 | avail_space = 0; | |
1048 | ||
1049 | if (avail_space < min_stripe_size) | |
1050 | continue; | |
1051 | ||
1052 | devices_info[i].dev = device; | |
1053 | devices_info[i].max_avail = avail_space; | |
1054 | ||
1055 | i++; | |
1056 | } | |
1057 | ||
1058 | nr_devices = i; | |
1059 | ||
1060 | btrfs_descending_sort_devices(devices_info, nr_devices); | |
1061 | ||
1062 | i = nr_devices - 1; | |
1063 | avail_space = 0; | |
1064 | while (nr_devices >= min_stripes) { | |
1065 | if (devices_info[i].max_avail >= min_stripe_size) { | |
1066 | int j; | |
1067 | u64 alloc_size; | |
1068 | ||
1069 | avail_space += devices_info[i].max_avail * min_stripes; | |
1070 | alloc_size = devices_info[i].max_avail; | |
1071 | for (j = i + 1 - min_stripes; j <= i; j++) | |
1072 | devices_info[j].max_avail -= alloc_size; | |
1073 | } | |
1074 | i--; | |
1075 | nr_devices--; | |
1076 | } | |
1077 | ||
1078 | kfree(devices_info); | |
1079 | *free_bytes = avail_space; | |
1080 | return 0; | |
1081 | } | |
1082 | ||
8fd17795 CM |
1083 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
1084 | { | |
1085 | struct btrfs_root *root = btrfs_sb(dentry->d_sb); | |
4b52dff6 | 1086 | struct btrfs_super_block *disk_super = &root->fs_info->super_copy; |
bd4d1088 JB |
1087 | struct list_head *head = &root->fs_info->space_info; |
1088 | struct btrfs_space_info *found; | |
1089 | u64 total_used = 0; | |
6d07bcec | 1090 | u64 total_free_data = 0; |
db94535d | 1091 | int bits = dentry->d_sb->s_blocksize_bits; |
9d03632e | 1092 | __be32 *fsid = (__be32 *)root->fs_info->fsid; |
6d07bcec | 1093 | int ret; |
8fd17795 | 1094 | |
6d07bcec MX |
1095 | /* holding chunk_muext to avoid allocating new chunks */ |
1096 | mutex_lock(&root->fs_info->chunk_mutex); | |
bd4d1088 | 1097 | rcu_read_lock(); |
89a55897 | 1098 | list_for_each_entry_rcu(found, head, list) { |
6d07bcec MX |
1099 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) { |
1100 | total_free_data += found->disk_total - found->disk_used; | |
1101 | total_free_data -= | |
1102 | btrfs_account_ro_block_groups_free_space(found); | |
1103 | } | |
1104 | ||
b742bb82 | 1105 | total_used += found->disk_used; |
89a55897 | 1106 | } |
bd4d1088 JB |
1107 | rcu_read_unlock(); |
1108 | ||
8fd17795 | 1109 | buf->f_namelen = BTRFS_NAME_LEN; |
db94535d | 1110 | buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits; |
bd4d1088 | 1111 | buf->f_bfree = buf->f_blocks - (total_used >> bits); |
8fd17795 CM |
1112 | buf->f_bsize = dentry->d_sb->s_blocksize; |
1113 | buf->f_type = BTRFS_SUPER_MAGIC; | |
6d07bcec MX |
1114 | buf->f_bavail = total_free_data; |
1115 | ret = btrfs_calc_avail_data_space(root, &total_free_data); | |
1116 | if (ret) { | |
1117 | mutex_unlock(&root->fs_info->chunk_mutex); | |
1118 | return ret; | |
1119 | } | |
1120 | buf->f_bavail += total_free_data; | |
1121 | buf->f_bavail = buf->f_bavail >> bits; | |
1122 | mutex_unlock(&root->fs_info->chunk_mutex); | |
d397712b | 1123 | |
9d03632e | 1124 | /* We treat it as constant endianness (it doesn't matter _which_) |
d397712b | 1125 | because we want the fsid to come out the same whether mounted |
9d03632e DW |
1126 | on a big-endian or little-endian host */ |
1127 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
1128 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
32d48fa1 DW |
1129 | /* Mask in the root object ID too, to disambiguate subvols */ |
1130 | buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32; | |
1131 | buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid; | |
1132 | ||
8fd17795 CM |
1133 | return 0; |
1134 | } | |
b5133862 | 1135 | |
2e635a27 CM |
1136 | static struct file_system_type btrfs_fs_type = { |
1137 | .owner = THIS_MODULE, | |
1138 | .name = "btrfs", | |
061dbc6b | 1139 | .mount = btrfs_mount, |
a061fc8d | 1140 | .kill_sb = kill_anon_super, |
2e635a27 CM |
1141 | .fs_flags = FS_REQUIRES_DEV, |
1142 | }; | |
a9218f6b | 1143 | |
d352ac68 CM |
1144 | /* |
1145 | * used by btrfsctl to scan devices when no FS is mounted | |
1146 | */ | |
8a4b83cc CM |
1147 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, |
1148 | unsigned long arg) | |
1149 | { | |
1150 | struct btrfs_ioctl_vol_args *vol; | |
1151 | struct btrfs_fs_devices *fs_devices; | |
c071fcfd | 1152 | int ret = -ENOTTY; |
8a4b83cc | 1153 | |
e441d54d CM |
1154 | if (!capable(CAP_SYS_ADMIN)) |
1155 | return -EPERM; | |
1156 | ||
dae7b665 LZ |
1157 | vol = memdup_user((void __user *)arg, sizeof(*vol)); |
1158 | if (IS_ERR(vol)) | |
1159 | return PTR_ERR(vol); | |
c071fcfd | 1160 | |
8a4b83cc CM |
1161 | switch (cmd) { |
1162 | case BTRFS_IOC_SCAN_DEV: | |
97288f2c | 1163 | ret = btrfs_scan_one_device(vol->name, FMODE_READ, |
8a4b83cc CM |
1164 | &btrfs_fs_type, &fs_devices); |
1165 | break; | |
1166 | } | |
dae7b665 | 1167 | |
8a4b83cc | 1168 | kfree(vol); |
f819d837 | 1169 | return ret; |
8a4b83cc CM |
1170 | } |
1171 | ||
0176260f | 1172 | static int btrfs_freeze(struct super_block *sb) |
ed0dab6b Y |
1173 | { |
1174 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
1175 | mutex_lock(&root->fs_info->transaction_kthread_mutex); |
1176 | mutex_lock(&root->fs_info->cleaner_mutex); | |
0176260f | 1177 | return 0; |
ed0dab6b Y |
1178 | } |
1179 | ||
0176260f | 1180 | static int btrfs_unfreeze(struct super_block *sb) |
ed0dab6b Y |
1181 | { |
1182 | struct btrfs_root *root = btrfs_sb(sb); | |
a74a4b97 CM |
1183 | mutex_unlock(&root->fs_info->cleaner_mutex); |
1184 | mutex_unlock(&root->fs_info->transaction_kthread_mutex); | |
0176260f | 1185 | return 0; |
ed0dab6b | 1186 | } |
2e635a27 | 1187 | |
b87221de | 1188 | static const struct super_operations btrfs_super_ops = { |
76dda93c | 1189 | .drop_inode = btrfs_drop_inode, |
bd555975 | 1190 | .evict_inode = btrfs_evict_inode, |
e20d96d6 | 1191 | .put_super = btrfs_put_super, |
d5719762 | 1192 | .sync_fs = btrfs_sync_fs, |
a9572a15 | 1193 | .show_options = btrfs_show_options, |
4730a4bc | 1194 | .write_inode = btrfs_write_inode, |
b5133862 | 1195 | .dirty_inode = btrfs_dirty_inode, |
2c90e5d6 CM |
1196 | .alloc_inode = btrfs_alloc_inode, |
1197 | .destroy_inode = btrfs_destroy_inode, | |
8fd17795 | 1198 | .statfs = btrfs_statfs, |
c146afad | 1199 | .remount_fs = btrfs_remount, |
0176260f LT |
1200 | .freeze_fs = btrfs_freeze, |
1201 | .unfreeze_fs = btrfs_unfreeze, | |
e20d96d6 | 1202 | }; |
a9218f6b CM |
1203 | |
1204 | static const struct file_operations btrfs_ctl_fops = { | |
1205 | .unlocked_ioctl = btrfs_control_ioctl, | |
1206 | .compat_ioctl = btrfs_control_ioctl, | |
1207 | .owner = THIS_MODULE, | |
6038f373 | 1208 | .llseek = noop_llseek, |
a9218f6b CM |
1209 | }; |
1210 | ||
1211 | static struct miscdevice btrfs_misc = { | |
578454ff | 1212 | .minor = BTRFS_MINOR, |
a9218f6b CM |
1213 | .name = "btrfs-control", |
1214 | .fops = &btrfs_ctl_fops | |
1215 | }; | |
1216 | ||
578454ff KS |
1217 | MODULE_ALIAS_MISCDEV(BTRFS_MINOR); |
1218 | MODULE_ALIAS("devname:btrfs-control"); | |
1219 | ||
a9218f6b CM |
1220 | static int btrfs_interface_init(void) |
1221 | { | |
1222 | return misc_register(&btrfs_misc); | |
1223 | } | |
1224 | ||
b2950863 | 1225 | static void btrfs_interface_exit(void) |
a9218f6b CM |
1226 | { |
1227 | if (misc_deregister(&btrfs_misc) < 0) | |
d397712b | 1228 | printk(KERN_INFO "misc_deregister failed for control device"); |
a9218f6b CM |
1229 | } |
1230 | ||
2e635a27 CM |
1231 | static int __init init_btrfs_fs(void) |
1232 | { | |
2c90e5d6 | 1233 | int err; |
58176a96 JB |
1234 | |
1235 | err = btrfs_init_sysfs(); | |
1236 | if (err) | |
1237 | return err; | |
1238 | ||
261507a0 | 1239 | err = btrfs_init_compress(); |
2c90e5d6 | 1240 | if (err) |
a74a4b97 | 1241 | goto free_sysfs; |
d1310b2e | 1242 | |
261507a0 LZ |
1243 | err = btrfs_init_cachep(); |
1244 | if (err) | |
1245 | goto free_compress; | |
1246 | ||
d1310b2e | 1247 | err = extent_io_init(); |
2f4cbe64 WB |
1248 | if (err) |
1249 | goto free_cachep; | |
1250 | ||
d1310b2e CM |
1251 | err = extent_map_init(); |
1252 | if (err) | |
1253 | goto free_extent_io; | |
1254 | ||
16cdcec7 | 1255 | err = btrfs_delayed_inode_init(); |
2f4cbe64 WB |
1256 | if (err) |
1257 | goto free_extent_map; | |
c8b97818 | 1258 | |
16cdcec7 MX |
1259 | err = btrfs_interface_init(); |
1260 | if (err) | |
1261 | goto free_delayed_inode; | |
1262 | ||
a9218f6b CM |
1263 | err = register_filesystem(&btrfs_fs_type); |
1264 | if (err) | |
1265 | goto unregister_ioctl; | |
b3c3da71 CM |
1266 | |
1267 | printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION); | |
2f4cbe64 WB |
1268 | return 0; |
1269 | ||
a9218f6b CM |
1270 | unregister_ioctl: |
1271 | btrfs_interface_exit(); | |
16cdcec7 MX |
1272 | free_delayed_inode: |
1273 | btrfs_delayed_inode_exit(); | |
2f4cbe64 WB |
1274 | free_extent_map: |
1275 | extent_map_exit(); | |
d1310b2e CM |
1276 | free_extent_io: |
1277 | extent_io_exit(); | |
2f4cbe64 WB |
1278 | free_cachep: |
1279 | btrfs_destroy_cachep(); | |
261507a0 LZ |
1280 | free_compress: |
1281 | btrfs_exit_compress(); | |
a74a4b97 | 1282 | free_sysfs: |
2f4cbe64 WB |
1283 | btrfs_exit_sysfs(); |
1284 | return err; | |
2e635a27 CM |
1285 | } |
1286 | ||
1287 | static void __exit exit_btrfs_fs(void) | |
1288 | { | |
39279cc3 | 1289 | btrfs_destroy_cachep(); |
16cdcec7 | 1290 | btrfs_delayed_inode_exit(); |
a52d9a80 | 1291 | extent_map_exit(); |
d1310b2e | 1292 | extent_io_exit(); |
a9218f6b | 1293 | btrfs_interface_exit(); |
2e635a27 | 1294 | unregister_filesystem(&btrfs_fs_type); |
58176a96 | 1295 | btrfs_exit_sysfs(); |
8a4b83cc | 1296 | btrfs_cleanup_fs_uuids(); |
261507a0 | 1297 | btrfs_exit_compress(); |
2e635a27 CM |
1298 | } |
1299 | ||
1300 | module_init(init_btrfs_fs) | |
1301 | module_exit(exit_btrfs_fs) | |
1302 | ||
1303 | MODULE_LICENSE("GPL"); |