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1 | // SPDX-License-Identifier: GPL-2.0 | |
2 | /* | |
3 | * Copyright (C) 2007 Oracle. All rights reserved. | |
4 | */ | |
5 | ||
6 | #include <linux/blkdev.h> | |
7 | #include <linux/module.h> | |
8 | #include <linux/fs.h> | |
9 | #include <linux/pagemap.h> | |
10 | #include <linux/highmem.h> | |
11 | #include <linux/time.h> | |
12 | #include <linux/init.h> | |
13 | #include <linux/seq_file.h> | |
14 | #include <linux/string.h> | |
15 | #include <linux/backing-dev.h> | |
16 | #include <linux/mount.h> | |
17 | #include <linux/writeback.h> | |
18 | #include <linux/statfs.h> | |
19 | #include <linux/compat.h> | |
20 | #include <linux/parser.h> | |
21 | #include <linux/ctype.h> | |
22 | #include <linux/namei.h> | |
23 | #include <linux/miscdevice.h> | |
24 | #include <linux/magic.h> | |
25 | #include <linux/slab.h> | |
26 | #include <linux/cleancache.h> | |
27 | #include <linux/ratelimit.h> | |
28 | #include <linux/crc32c.h> | |
29 | #include <linux/btrfs.h> | |
30 | #include "delayed-inode.h" | |
31 | #include "ctree.h" | |
32 | #include "disk-io.h" | |
33 | #include "transaction.h" | |
34 | #include "btrfs_inode.h" | |
35 | #include "print-tree.h" | |
36 | #include "props.h" | |
37 | #include "xattr.h" | |
38 | #include "volumes.h" | |
39 | #include "export.h" | |
40 | #include "compression.h" | |
41 | #include "rcu-string.h" | |
42 | #include "dev-replace.h" | |
43 | #include "free-space-cache.h" | |
44 | #include "backref.h" | |
45 | #include "space-info.h" | |
46 | #include "tests/btrfs-tests.h" | |
47 | ||
48 | #include "qgroup.h" | |
49 | #define CREATE_TRACE_POINTS | |
50 | #include <trace/events/btrfs.h> | |
51 | ||
52 | static const struct super_operations btrfs_super_ops; | |
53 | ||
54 | /* | |
55 | * Types for mounting the default subvolume and a subvolume explicitly | |
56 | * requested by subvol=/path. That way the callchain is straightforward and we | |
57 | * don't have to play tricks with the mount options and recursive calls to | |
58 | * btrfs_mount. | |
59 | * | |
60 | * The new btrfs_root_fs_type also servers as a tag for the bdev_holder. | |
61 | */ | |
62 | static struct file_system_type btrfs_fs_type; | |
63 | static struct file_system_type btrfs_root_fs_type; | |
64 | ||
65 | static int btrfs_remount(struct super_block *sb, int *flags, char *data); | |
66 | ||
67 | const char *btrfs_decode_error(int errno) | |
68 | { | |
69 | char *errstr = "unknown"; | |
70 | ||
71 | switch (errno) { | |
72 | case -EIO: | |
73 | errstr = "IO failure"; | |
74 | break; | |
75 | case -ENOMEM: | |
76 | errstr = "Out of memory"; | |
77 | break; | |
78 | case -EROFS: | |
79 | errstr = "Readonly filesystem"; | |
80 | break; | |
81 | case -EEXIST: | |
82 | errstr = "Object already exists"; | |
83 | break; | |
84 | case -ENOSPC: | |
85 | errstr = "No space left"; | |
86 | break; | |
87 | case -ENOENT: | |
88 | errstr = "No such entry"; | |
89 | break; | |
90 | } | |
91 | ||
92 | return errstr; | |
93 | } | |
94 | ||
95 | /* | |
96 | * __btrfs_handle_fs_error decodes expected errors from the caller and | |
97 | * invokes the appropriate error response. | |
98 | */ | |
99 | __cold | |
100 | void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function, | |
101 | unsigned int line, int errno, const char *fmt, ...) | |
102 | { | |
103 | struct super_block *sb = fs_info->sb; | |
104 | #ifdef CONFIG_PRINTK | |
105 | const char *errstr; | |
106 | #endif | |
107 | ||
108 | /* | |
109 | * Special case: if the error is EROFS, and we're already | |
110 | * under SB_RDONLY, then it is safe here. | |
111 | */ | |
112 | if (errno == -EROFS && sb_rdonly(sb)) | |
113 | return; | |
114 | ||
115 | #ifdef CONFIG_PRINTK | |
116 | errstr = btrfs_decode_error(errno); | |
117 | if (fmt) { | |
118 | struct va_format vaf; | |
119 | va_list args; | |
120 | ||
121 | va_start(args, fmt); | |
122 | vaf.fmt = fmt; | |
123 | vaf.va = &args; | |
124 | ||
125 | pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n", | |
126 | sb->s_id, function, line, errno, errstr, &vaf); | |
127 | va_end(args); | |
128 | } else { | |
129 | pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n", | |
130 | sb->s_id, function, line, errno, errstr); | |
131 | } | |
132 | #endif | |
133 | ||
134 | /* | |
135 | * Today we only save the error info to memory. Long term we'll | |
136 | * also send it down to the disk | |
137 | */ | |
138 | set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state); | |
139 | ||
140 | /* Don't go through full error handling during mount */ | |
141 | if (!(sb->s_flags & SB_BORN)) | |
142 | return; | |
143 | ||
144 | if (sb_rdonly(sb)) | |
145 | return; | |
146 | ||
147 | /* btrfs handle error by forcing the filesystem readonly */ | |
148 | sb->s_flags |= SB_RDONLY; | |
149 | btrfs_info(fs_info, "forced readonly"); | |
150 | /* | |
151 | * Note that a running device replace operation is not canceled here | |
152 | * although there is no way to update the progress. It would add the | |
153 | * risk of a deadlock, therefore the canceling is omitted. The only | |
154 | * penalty is that some I/O remains active until the procedure | |
155 | * completes. The next time when the filesystem is mounted writable | |
156 | * again, the device replace operation continues. | |
157 | */ | |
158 | } | |
159 | ||
160 | #ifdef CONFIG_PRINTK | |
161 | static const char * const logtypes[] = { | |
162 | "emergency", | |
163 | "alert", | |
164 | "critical", | |
165 | "error", | |
166 | "warning", | |
167 | "notice", | |
168 | "info", | |
169 | "debug", | |
170 | }; | |
171 | ||
172 | ||
173 | /* | |
174 | * Use one ratelimit state per log level so that a flood of less important | |
175 | * messages doesn't cause more important ones to be dropped. | |
176 | */ | |
177 | static struct ratelimit_state printk_limits[] = { | |
178 | RATELIMIT_STATE_INIT(printk_limits[0], DEFAULT_RATELIMIT_INTERVAL, 100), | |
179 | RATELIMIT_STATE_INIT(printk_limits[1], DEFAULT_RATELIMIT_INTERVAL, 100), | |
180 | RATELIMIT_STATE_INIT(printk_limits[2], DEFAULT_RATELIMIT_INTERVAL, 100), | |
181 | RATELIMIT_STATE_INIT(printk_limits[3], DEFAULT_RATELIMIT_INTERVAL, 100), | |
182 | RATELIMIT_STATE_INIT(printk_limits[4], DEFAULT_RATELIMIT_INTERVAL, 100), | |
183 | RATELIMIT_STATE_INIT(printk_limits[5], DEFAULT_RATELIMIT_INTERVAL, 100), | |
184 | RATELIMIT_STATE_INIT(printk_limits[6], DEFAULT_RATELIMIT_INTERVAL, 100), | |
185 | RATELIMIT_STATE_INIT(printk_limits[7], DEFAULT_RATELIMIT_INTERVAL, 100), | |
186 | }; | |
187 | ||
188 | void btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...) | |
189 | { | |
190 | char lvl[PRINTK_MAX_SINGLE_HEADER_LEN + 1] = "\0"; | |
191 | struct va_format vaf; | |
192 | va_list args; | |
193 | int kern_level; | |
194 | const char *type = logtypes[4]; | |
195 | struct ratelimit_state *ratelimit = &printk_limits[4]; | |
196 | ||
197 | va_start(args, fmt); | |
198 | ||
199 | while ((kern_level = printk_get_level(fmt)) != 0) { | |
200 | size_t size = printk_skip_level(fmt) - fmt; | |
201 | ||
202 | if (kern_level >= '0' && kern_level <= '7') { | |
203 | memcpy(lvl, fmt, size); | |
204 | lvl[size] = '\0'; | |
205 | type = logtypes[kern_level - '0']; | |
206 | ratelimit = &printk_limits[kern_level - '0']; | |
207 | } | |
208 | fmt += size; | |
209 | } | |
210 | ||
211 | vaf.fmt = fmt; | |
212 | vaf.va = &args; | |
213 | ||
214 | if (__ratelimit(ratelimit)) | |
215 | printk("%sBTRFS %s (device %s): %pV\n", lvl, type, | |
216 | fs_info ? fs_info->sb->s_id : "<unknown>", &vaf); | |
217 | ||
218 | va_end(args); | |
219 | } | |
220 | #endif | |
221 | ||
222 | /* | |
223 | * We only mark the transaction aborted and then set the file system read-only. | |
224 | * This will prevent new transactions from starting or trying to join this | |
225 | * one. | |
226 | * | |
227 | * This means that error recovery at the call site is limited to freeing | |
228 | * any local memory allocations and passing the error code up without | |
229 | * further cleanup. The transaction should complete as it normally would | |
230 | * in the call path but will return -EIO. | |
231 | * | |
232 | * We'll complete the cleanup in btrfs_end_transaction and | |
233 | * btrfs_commit_transaction. | |
234 | */ | |
235 | __cold | |
236 | void __btrfs_abort_transaction(struct btrfs_trans_handle *trans, | |
237 | const char *function, | |
238 | unsigned int line, int errno) | |
239 | { | |
240 | struct btrfs_fs_info *fs_info = trans->fs_info; | |
241 | ||
242 | trans->aborted = errno; | |
243 | /* Nothing used. The other threads that have joined this | |
244 | * transaction may be able to continue. */ | |
245 | if (!trans->dirty && list_empty(&trans->new_bgs)) { | |
246 | const char *errstr; | |
247 | ||
248 | errstr = btrfs_decode_error(errno); | |
249 | btrfs_warn(fs_info, | |
250 | "%s:%d: Aborting unused transaction(%s).", | |
251 | function, line, errstr); | |
252 | return; | |
253 | } | |
254 | WRITE_ONCE(trans->transaction->aborted, errno); | |
255 | /* Wake up anybody who may be waiting on this transaction */ | |
256 | wake_up(&fs_info->transaction_wait); | |
257 | wake_up(&fs_info->transaction_blocked_wait); | |
258 | __btrfs_handle_fs_error(fs_info, function, line, errno, NULL); | |
259 | } | |
260 | /* | |
261 | * __btrfs_panic decodes unexpected, fatal errors from the caller, | |
262 | * issues an alert, and either panics or BUGs, depending on mount options. | |
263 | */ | |
264 | __cold | |
265 | void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function, | |
266 | unsigned int line, int errno, const char *fmt, ...) | |
267 | { | |
268 | char *s_id = "<unknown>"; | |
269 | const char *errstr; | |
270 | struct va_format vaf = { .fmt = fmt }; | |
271 | va_list args; | |
272 | ||
273 | if (fs_info) | |
274 | s_id = fs_info->sb->s_id; | |
275 | ||
276 | va_start(args, fmt); | |
277 | vaf.va = &args; | |
278 | ||
279 | errstr = btrfs_decode_error(errno); | |
280 | if (fs_info && (btrfs_test_opt(fs_info, PANIC_ON_FATAL_ERROR))) | |
281 | panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n", | |
282 | s_id, function, line, &vaf, errno, errstr); | |
283 | ||
284 | btrfs_crit(fs_info, "panic in %s:%d: %pV (errno=%d %s)", | |
285 | function, line, &vaf, errno, errstr); | |
286 | va_end(args); | |
287 | /* Caller calls BUG() */ | |
288 | } | |
289 | ||
290 | static void btrfs_put_super(struct super_block *sb) | |
291 | { | |
292 | close_ctree(btrfs_sb(sb)); | |
293 | } | |
294 | ||
295 | enum { | |
296 | Opt_acl, Opt_noacl, | |
297 | Opt_clear_cache, | |
298 | Opt_commit_interval, | |
299 | Opt_compress, | |
300 | Opt_compress_force, | |
301 | Opt_compress_force_type, | |
302 | Opt_compress_type, | |
303 | Opt_degraded, | |
304 | Opt_device, | |
305 | Opt_fatal_errors, | |
306 | Opt_flushoncommit, Opt_noflushoncommit, | |
307 | Opt_inode_cache, Opt_noinode_cache, | |
308 | Opt_max_inline, | |
309 | Opt_barrier, Opt_nobarrier, | |
310 | Opt_datacow, Opt_nodatacow, | |
311 | Opt_datasum, Opt_nodatasum, | |
312 | Opt_defrag, Opt_nodefrag, | |
313 | Opt_discard, Opt_nodiscard, | |
314 | Opt_nologreplay, | |
315 | Opt_norecovery, | |
316 | Opt_ratio, | |
317 | Opt_rescan_uuid_tree, | |
318 | Opt_skip_balance, | |
319 | Opt_space_cache, Opt_no_space_cache, | |
320 | Opt_space_cache_version, | |
321 | Opt_ssd, Opt_nossd, | |
322 | Opt_ssd_spread, Opt_nossd_spread, | |
323 | Opt_subvol, | |
324 | Opt_subvol_empty, | |
325 | Opt_subvolid, | |
326 | Opt_thread_pool, | |
327 | Opt_treelog, Opt_notreelog, | |
328 | Opt_usebackuproot, | |
329 | Opt_user_subvol_rm_allowed, | |
330 | ||
331 | /* Deprecated options */ | |
332 | Opt_alloc_start, | |
333 | Opt_recovery, | |
334 | Opt_subvolrootid, | |
335 | ||
336 | /* Debugging options */ | |
337 | Opt_check_integrity, | |
338 | Opt_check_integrity_including_extent_data, | |
339 | Opt_check_integrity_print_mask, | |
340 | Opt_enospc_debug, Opt_noenospc_debug, | |
341 | #ifdef CONFIG_BTRFS_DEBUG | |
342 | Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all, | |
343 | #endif | |
344 | #ifdef CONFIG_BTRFS_FS_REF_VERIFY | |
345 | Opt_ref_verify, | |
346 | #endif | |
347 | Opt_err, | |
348 | }; | |
349 | ||
350 | static const match_table_t tokens = { | |
351 | {Opt_acl, "acl"}, | |
352 | {Opt_noacl, "noacl"}, | |
353 | {Opt_clear_cache, "clear_cache"}, | |
354 | {Opt_commit_interval, "commit=%u"}, | |
355 | {Opt_compress, "compress"}, | |
356 | {Opt_compress_type, "compress=%s"}, | |
357 | {Opt_compress_force, "compress-force"}, | |
358 | {Opt_compress_force_type, "compress-force=%s"}, | |
359 | {Opt_degraded, "degraded"}, | |
360 | {Opt_device, "device=%s"}, | |
361 | {Opt_fatal_errors, "fatal_errors=%s"}, | |
362 | {Opt_flushoncommit, "flushoncommit"}, | |
363 | {Opt_noflushoncommit, "noflushoncommit"}, | |
364 | {Opt_inode_cache, "inode_cache"}, | |
365 | {Opt_noinode_cache, "noinode_cache"}, | |
366 | {Opt_max_inline, "max_inline=%s"}, | |
367 | {Opt_barrier, "barrier"}, | |
368 | {Opt_nobarrier, "nobarrier"}, | |
369 | {Opt_datacow, "datacow"}, | |
370 | {Opt_nodatacow, "nodatacow"}, | |
371 | {Opt_datasum, "datasum"}, | |
372 | {Opt_nodatasum, "nodatasum"}, | |
373 | {Opt_defrag, "autodefrag"}, | |
374 | {Opt_nodefrag, "noautodefrag"}, | |
375 | {Opt_discard, "discard"}, | |
376 | {Opt_nodiscard, "nodiscard"}, | |
377 | {Opt_nologreplay, "nologreplay"}, | |
378 | {Opt_norecovery, "norecovery"}, | |
379 | {Opt_ratio, "metadata_ratio=%u"}, | |
380 | {Opt_rescan_uuid_tree, "rescan_uuid_tree"}, | |
381 | {Opt_skip_balance, "skip_balance"}, | |
382 | {Opt_space_cache, "space_cache"}, | |
383 | {Opt_no_space_cache, "nospace_cache"}, | |
384 | {Opt_space_cache_version, "space_cache=%s"}, | |
385 | {Opt_ssd, "ssd"}, | |
386 | {Opt_nossd, "nossd"}, | |
387 | {Opt_ssd_spread, "ssd_spread"}, | |
388 | {Opt_nossd_spread, "nossd_spread"}, | |
389 | {Opt_subvol, "subvol=%s"}, | |
390 | {Opt_subvol_empty, "subvol="}, | |
391 | {Opt_subvolid, "subvolid=%s"}, | |
392 | {Opt_thread_pool, "thread_pool=%u"}, | |
393 | {Opt_treelog, "treelog"}, | |
394 | {Opt_notreelog, "notreelog"}, | |
395 | {Opt_usebackuproot, "usebackuproot"}, | |
396 | {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, | |
397 | ||
398 | /* Deprecated options */ | |
399 | {Opt_alloc_start, "alloc_start=%s"}, | |
400 | {Opt_recovery, "recovery"}, | |
401 | {Opt_subvolrootid, "subvolrootid=%d"}, | |
402 | ||
403 | /* Debugging options */ | |
404 | {Opt_check_integrity, "check_int"}, | |
405 | {Opt_check_integrity_including_extent_data, "check_int_data"}, | |
406 | {Opt_check_integrity_print_mask, "check_int_print_mask=%u"}, | |
407 | {Opt_enospc_debug, "enospc_debug"}, | |
408 | {Opt_noenospc_debug, "noenospc_debug"}, | |
409 | #ifdef CONFIG_BTRFS_DEBUG | |
410 | {Opt_fragment_data, "fragment=data"}, | |
411 | {Opt_fragment_metadata, "fragment=metadata"}, | |
412 | {Opt_fragment_all, "fragment=all"}, | |
413 | #endif | |
414 | #ifdef CONFIG_BTRFS_FS_REF_VERIFY | |
415 | {Opt_ref_verify, "ref_verify"}, | |
416 | #endif | |
417 | {Opt_err, NULL}, | |
418 | }; | |
419 | ||
420 | /* | |
421 | * Regular mount options parser. Everything that is needed only when | |
422 | * reading in a new superblock is parsed here. | |
423 | * XXX JDM: This needs to be cleaned up for remount. | |
424 | */ | |
425 | int btrfs_parse_options(struct btrfs_fs_info *info, char *options, | |
426 | unsigned long new_flags) | |
427 | { | |
428 | substring_t args[MAX_OPT_ARGS]; | |
429 | char *p, *num; | |
430 | u64 cache_gen; | |
431 | int intarg; | |
432 | int ret = 0; | |
433 | char *compress_type; | |
434 | bool compress_force = false; | |
435 | enum btrfs_compression_type saved_compress_type; | |
436 | bool saved_compress_force; | |
437 | int no_compress = 0; | |
438 | ||
439 | cache_gen = btrfs_super_cache_generation(info->super_copy); | |
440 | if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE)) | |
441 | btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); | |
442 | else if (cache_gen) | |
443 | btrfs_set_opt(info->mount_opt, SPACE_CACHE); | |
444 | ||
445 | /* | |
446 | * Even the options are empty, we still need to do extra check | |
447 | * against new flags | |
448 | */ | |
449 | if (!options) | |
450 | goto check; | |
451 | ||
452 | while ((p = strsep(&options, ",")) != NULL) { | |
453 | int token; | |
454 | if (!*p) | |
455 | continue; | |
456 | ||
457 | token = match_token(p, tokens, args); | |
458 | switch (token) { | |
459 | case Opt_degraded: | |
460 | btrfs_info(info, "allowing degraded mounts"); | |
461 | btrfs_set_opt(info->mount_opt, DEGRADED); | |
462 | break; | |
463 | case Opt_subvol: | |
464 | case Opt_subvol_empty: | |
465 | case Opt_subvolid: | |
466 | case Opt_subvolrootid: | |
467 | case Opt_device: | |
468 | /* | |
469 | * These are parsed by btrfs_parse_subvol_options or | |
470 | * btrfs_parse_device_options and can be ignored here. | |
471 | */ | |
472 | break; | |
473 | case Opt_nodatasum: | |
474 | btrfs_set_and_info(info, NODATASUM, | |
475 | "setting nodatasum"); | |
476 | break; | |
477 | case Opt_datasum: | |
478 | if (btrfs_test_opt(info, NODATASUM)) { | |
479 | if (btrfs_test_opt(info, NODATACOW)) | |
480 | btrfs_info(info, | |
481 | "setting datasum, datacow enabled"); | |
482 | else | |
483 | btrfs_info(info, "setting datasum"); | |
484 | } | |
485 | btrfs_clear_opt(info->mount_opt, NODATACOW); | |
486 | btrfs_clear_opt(info->mount_opt, NODATASUM); | |
487 | break; | |
488 | case Opt_nodatacow: | |
489 | if (!btrfs_test_opt(info, NODATACOW)) { | |
490 | if (!btrfs_test_opt(info, COMPRESS) || | |
491 | !btrfs_test_opt(info, FORCE_COMPRESS)) { | |
492 | btrfs_info(info, | |
493 | "setting nodatacow, compression disabled"); | |
494 | } else { | |
495 | btrfs_info(info, "setting nodatacow"); | |
496 | } | |
497 | } | |
498 | btrfs_clear_opt(info->mount_opt, COMPRESS); | |
499 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); | |
500 | btrfs_set_opt(info->mount_opt, NODATACOW); | |
501 | btrfs_set_opt(info->mount_opt, NODATASUM); | |
502 | break; | |
503 | case Opt_datacow: | |
504 | btrfs_clear_and_info(info, NODATACOW, | |
505 | "setting datacow"); | |
506 | break; | |
507 | case Opt_compress_force: | |
508 | case Opt_compress_force_type: | |
509 | compress_force = true; | |
510 | /* Fallthrough */ | |
511 | case Opt_compress: | |
512 | case Opt_compress_type: | |
513 | saved_compress_type = btrfs_test_opt(info, | |
514 | COMPRESS) ? | |
515 | info->compress_type : BTRFS_COMPRESS_NONE; | |
516 | saved_compress_force = | |
517 | btrfs_test_opt(info, FORCE_COMPRESS); | |
518 | if (token == Opt_compress || | |
519 | token == Opt_compress_force || | |
520 | strncmp(args[0].from, "zlib", 4) == 0) { | |
521 | compress_type = "zlib"; | |
522 | ||
523 | info->compress_type = BTRFS_COMPRESS_ZLIB; | |
524 | info->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL; | |
525 | /* | |
526 | * args[0] contains uninitialized data since | |
527 | * for these tokens we don't expect any | |
528 | * parameter. | |
529 | */ | |
530 | if (token != Opt_compress && | |
531 | token != Opt_compress_force) | |
532 | info->compress_level = | |
533 | btrfs_compress_str2level( | |
534 | BTRFS_COMPRESS_ZLIB, | |
535 | args[0].from + 4); | |
536 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
537 | btrfs_clear_opt(info->mount_opt, NODATACOW); | |
538 | btrfs_clear_opt(info->mount_opt, NODATASUM); | |
539 | no_compress = 0; | |
540 | } else if (strncmp(args[0].from, "lzo", 3) == 0) { | |
541 | compress_type = "lzo"; | |
542 | info->compress_type = BTRFS_COMPRESS_LZO; | |
543 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
544 | btrfs_clear_opt(info->mount_opt, NODATACOW); | |
545 | btrfs_clear_opt(info->mount_opt, NODATASUM); | |
546 | btrfs_set_fs_incompat(info, COMPRESS_LZO); | |
547 | no_compress = 0; | |
548 | } else if (strncmp(args[0].from, "zstd", 4) == 0) { | |
549 | compress_type = "zstd"; | |
550 | info->compress_type = BTRFS_COMPRESS_ZSTD; | |
551 | info->compress_level = | |
552 | btrfs_compress_str2level( | |
553 | BTRFS_COMPRESS_ZSTD, | |
554 | args[0].from + 4); | |
555 | btrfs_set_opt(info->mount_opt, COMPRESS); | |
556 | btrfs_clear_opt(info->mount_opt, NODATACOW); | |
557 | btrfs_clear_opt(info->mount_opt, NODATASUM); | |
558 | btrfs_set_fs_incompat(info, COMPRESS_ZSTD); | |
559 | no_compress = 0; | |
560 | } else if (strncmp(args[0].from, "no", 2) == 0) { | |
561 | compress_type = "no"; | |
562 | btrfs_clear_opt(info->mount_opt, COMPRESS); | |
563 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); | |
564 | compress_force = false; | |
565 | no_compress++; | |
566 | } else { | |
567 | ret = -EINVAL; | |
568 | goto out; | |
569 | } | |
570 | ||
571 | if (compress_force) { | |
572 | btrfs_set_opt(info->mount_opt, FORCE_COMPRESS); | |
573 | } else { | |
574 | /* | |
575 | * If we remount from compress-force=xxx to | |
576 | * compress=xxx, we need clear FORCE_COMPRESS | |
577 | * flag, otherwise, there is no way for users | |
578 | * to disable forcible compression separately. | |
579 | */ | |
580 | btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS); | |
581 | } | |
582 | if ((btrfs_test_opt(info, COMPRESS) && | |
583 | (info->compress_type != saved_compress_type || | |
584 | compress_force != saved_compress_force)) || | |
585 | (!btrfs_test_opt(info, COMPRESS) && | |
586 | no_compress == 1)) { | |
587 | btrfs_info(info, "%s %s compression, level %d", | |
588 | (compress_force) ? "force" : "use", | |
589 | compress_type, info->compress_level); | |
590 | } | |
591 | compress_force = false; | |
592 | break; | |
593 | case Opt_ssd: | |
594 | btrfs_set_and_info(info, SSD, | |
595 | "enabling ssd optimizations"); | |
596 | btrfs_clear_opt(info->mount_opt, NOSSD); | |
597 | break; | |
598 | case Opt_ssd_spread: | |
599 | btrfs_set_and_info(info, SSD, | |
600 | "enabling ssd optimizations"); | |
601 | btrfs_set_and_info(info, SSD_SPREAD, | |
602 | "using spread ssd allocation scheme"); | |
603 | btrfs_clear_opt(info->mount_opt, NOSSD); | |
604 | break; | |
605 | case Opt_nossd: | |
606 | btrfs_set_opt(info->mount_opt, NOSSD); | |
607 | btrfs_clear_and_info(info, SSD, | |
608 | "not using ssd optimizations"); | |
609 | /* Fallthrough */ | |
610 | case Opt_nossd_spread: | |
611 | btrfs_clear_and_info(info, SSD_SPREAD, | |
612 | "not using spread ssd allocation scheme"); | |
613 | break; | |
614 | case Opt_barrier: | |
615 | btrfs_clear_and_info(info, NOBARRIER, | |
616 | "turning on barriers"); | |
617 | break; | |
618 | case Opt_nobarrier: | |
619 | btrfs_set_and_info(info, NOBARRIER, | |
620 | "turning off barriers"); | |
621 | break; | |
622 | case Opt_thread_pool: | |
623 | ret = match_int(&args[0], &intarg); | |
624 | if (ret) { | |
625 | goto out; | |
626 | } else if (intarg == 0) { | |
627 | ret = -EINVAL; | |
628 | goto out; | |
629 | } | |
630 | info->thread_pool_size = intarg; | |
631 | break; | |
632 | case Opt_max_inline: | |
633 | num = match_strdup(&args[0]); | |
634 | if (num) { | |
635 | info->max_inline = memparse(num, NULL); | |
636 | kfree(num); | |
637 | ||
638 | if (info->max_inline) { | |
639 | info->max_inline = min_t(u64, | |
640 | info->max_inline, | |
641 | info->sectorsize); | |
642 | } | |
643 | btrfs_info(info, "max_inline at %llu", | |
644 | info->max_inline); | |
645 | } else { | |
646 | ret = -ENOMEM; | |
647 | goto out; | |
648 | } | |
649 | break; | |
650 | case Opt_alloc_start: | |
651 | btrfs_info(info, | |
652 | "option alloc_start is obsolete, ignored"); | |
653 | break; | |
654 | case Opt_acl: | |
655 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL | |
656 | info->sb->s_flags |= SB_POSIXACL; | |
657 | break; | |
658 | #else | |
659 | btrfs_err(info, "support for ACL not compiled in!"); | |
660 | ret = -EINVAL; | |
661 | goto out; | |
662 | #endif | |
663 | case Opt_noacl: | |
664 | info->sb->s_flags &= ~SB_POSIXACL; | |
665 | break; | |
666 | case Opt_notreelog: | |
667 | btrfs_set_and_info(info, NOTREELOG, | |
668 | "disabling tree log"); | |
669 | break; | |
670 | case Opt_treelog: | |
671 | btrfs_clear_and_info(info, NOTREELOG, | |
672 | "enabling tree log"); | |
673 | break; | |
674 | case Opt_norecovery: | |
675 | case Opt_nologreplay: | |
676 | btrfs_set_and_info(info, NOLOGREPLAY, | |
677 | "disabling log replay at mount time"); | |
678 | break; | |
679 | case Opt_flushoncommit: | |
680 | btrfs_set_and_info(info, FLUSHONCOMMIT, | |
681 | "turning on flush-on-commit"); | |
682 | break; | |
683 | case Opt_noflushoncommit: | |
684 | btrfs_clear_and_info(info, FLUSHONCOMMIT, | |
685 | "turning off flush-on-commit"); | |
686 | break; | |
687 | case Opt_ratio: | |
688 | ret = match_int(&args[0], &intarg); | |
689 | if (ret) | |
690 | goto out; | |
691 | info->metadata_ratio = intarg; | |
692 | btrfs_info(info, "metadata ratio %u", | |
693 | info->metadata_ratio); | |
694 | break; | |
695 | case Opt_discard: | |
696 | btrfs_set_and_info(info, DISCARD, | |
697 | "turning on discard"); | |
698 | break; | |
699 | case Opt_nodiscard: | |
700 | btrfs_clear_and_info(info, DISCARD, | |
701 | "turning off discard"); | |
702 | break; | |
703 | case Opt_space_cache: | |
704 | case Opt_space_cache_version: | |
705 | if (token == Opt_space_cache || | |
706 | strcmp(args[0].from, "v1") == 0) { | |
707 | btrfs_clear_opt(info->mount_opt, | |
708 | FREE_SPACE_TREE); | |
709 | btrfs_set_and_info(info, SPACE_CACHE, | |
710 | "enabling disk space caching"); | |
711 | } else if (strcmp(args[0].from, "v2") == 0) { | |
712 | btrfs_clear_opt(info->mount_opt, | |
713 | SPACE_CACHE); | |
714 | btrfs_set_and_info(info, FREE_SPACE_TREE, | |
715 | "enabling free space tree"); | |
716 | } else { | |
717 | ret = -EINVAL; | |
718 | goto out; | |
719 | } | |
720 | break; | |
721 | case Opt_rescan_uuid_tree: | |
722 | btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE); | |
723 | break; | |
724 | case Opt_no_space_cache: | |
725 | if (btrfs_test_opt(info, SPACE_CACHE)) { | |
726 | btrfs_clear_and_info(info, SPACE_CACHE, | |
727 | "disabling disk space caching"); | |
728 | } | |
729 | if (btrfs_test_opt(info, FREE_SPACE_TREE)) { | |
730 | btrfs_clear_and_info(info, FREE_SPACE_TREE, | |
731 | "disabling free space tree"); | |
732 | } | |
733 | break; | |
734 | case Opt_inode_cache: | |
735 | btrfs_set_pending_and_info(info, INODE_MAP_CACHE, | |
736 | "enabling inode map caching"); | |
737 | break; | |
738 | case Opt_noinode_cache: | |
739 | btrfs_clear_pending_and_info(info, INODE_MAP_CACHE, | |
740 | "disabling inode map caching"); | |
741 | break; | |
742 | case Opt_clear_cache: | |
743 | btrfs_set_and_info(info, CLEAR_CACHE, | |
744 | "force clearing of disk cache"); | |
745 | break; | |
746 | case Opt_user_subvol_rm_allowed: | |
747 | btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED); | |
748 | break; | |
749 | case Opt_enospc_debug: | |
750 | btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG); | |
751 | break; | |
752 | case Opt_noenospc_debug: | |
753 | btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG); | |
754 | break; | |
755 | case Opt_defrag: | |
756 | btrfs_set_and_info(info, AUTO_DEFRAG, | |
757 | "enabling auto defrag"); | |
758 | break; | |
759 | case Opt_nodefrag: | |
760 | btrfs_clear_and_info(info, AUTO_DEFRAG, | |
761 | "disabling auto defrag"); | |
762 | break; | |
763 | case Opt_recovery: | |
764 | btrfs_warn(info, | |
765 | "'recovery' is deprecated, use 'usebackuproot' instead"); | |
766 | /* fall through */ | |
767 | case Opt_usebackuproot: | |
768 | btrfs_info(info, | |
769 | "trying to use backup root at mount time"); | |
770 | btrfs_set_opt(info->mount_opt, USEBACKUPROOT); | |
771 | break; | |
772 | case Opt_skip_balance: | |
773 | btrfs_set_opt(info->mount_opt, SKIP_BALANCE); | |
774 | break; | |
775 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY | |
776 | case Opt_check_integrity_including_extent_data: | |
777 | btrfs_info(info, | |
778 | "enabling check integrity including extent data"); | |
779 | btrfs_set_opt(info->mount_opt, | |
780 | CHECK_INTEGRITY_INCLUDING_EXTENT_DATA); | |
781 | btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); | |
782 | break; | |
783 | case Opt_check_integrity: | |
784 | btrfs_info(info, "enabling check integrity"); | |
785 | btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY); | |
786 | break; | |
787 | case Opt_check_integrity_print_mask: | |
788 | ret = match_int(&args[0], &intarg); | |
789 | if (ret) | |
790 | goto out; | |
791 | info->check_integrity_print_mask = intarg; | |
792 | btrfs_info(info, "check_integrity_print_mask 0x%x", | |
793 | info->check_integrity_print_mask); | |
794 | break; | |
795 | #else | |
796 | case Opt_check_integrity_including_extent_data: | |
797 | case Opt_check_integrity: | |
798 | case Opt_check_integrity_print_mask: | |
799 | btrfs_err(info, | |
800 | "support for check_integrity* not compiled in!"); | |
801 | ret = -EINVAL; | |
802 | goto out; | |
803 | #endif | |
804 | case Opt_fatal_errors: | |
805 | if (strcmp(args[0].from, "panic") == 0) | |
806 | btrfs_set_opt(info->mount_opt, | |
807 | PANIC_ON_FATAL_ERROR); | |
808 | else if (strcmp(args[0].from, "bug") == 0) | |
809 | btrfs_clear_opt(info->mount_opt, | |
810 | PANIC_ON_FATAL_ERROR); | |
811 | else { | |
812 | ret = -EINVAL; | |
813 | goto out; | |
814 | } | |
815 | break; | |
816 | case Opt_commit_interval: | |
817 | intarg = 0; | |
818 | ret = match_int(&args[0], &intarg); | |
819 | if (ret) | |
820 | goto out; | |
821 | if (intarg == 0) { | |
822 | btrfs_info(info, | |
823 | "using default commit interval %us", | |
824 | BTRFS_DEFAULT_COMMIT_INTERVAL); | |
825 | intarg = BTRFS_DEFAULT_COMMIT_INTERVAL; | |
826 | } else if (intarg > 300) { | |
827 | btrfs_warn(info, "excessive commit interval %d", | |
828 | intarg); | |
829 | } | |
830 | info->commit_interval = intarg; | |
831 | break; | |
832 | #ifdef CONFIG_BTRFS_DEBUG | |
833 | case Opt_fragment_all: | |
834 | btrfs_info(info, "fragmenting all space"); | |
835 | btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); | |
836 | btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA); | |
837 | break; | |
838 | case Opt_fragment_metadata: | |
839 | btrfs_info(info, "fragmenting metadata"); | |
840 | btrfs_set_opt(info->mount_opt, | |
841 | FRAGMENT_METADATA); | |
842 | break; | |
843 | case Opt_fragment_data: | |
844 | btrfs_info(info, "fragmenting data"); | |
845 | btrfs_set_opt(info->mount_opt, FRAGMENT_DATA); | |
846 | break; | |
847 | #endif | |
848 | #ifdef CONFIG_BTRFS_FS_REF_VERIFY | |
849 | case Opt_ref_verify: | |
850 | btrfs_info(info, "doing ref verification"); | |
851 | btrfs_set_opt(info->mount_opt, REF_VERIFY); | |
852 | break; | |
853 | #endif | |
854 | case Opt_err: | |
855 | btrfs_info(info, "unrecognized mount option '%s'", p); | |
856 | ret = -EINVAL; | |
857 | goto out; | |
858 | default: | |
859 | break; | |
860 | } | |
861 | } | |
862 | check: | |
863 | /* | |
864 | * Extra check for current option against current flag | |
865 | */ | |
866 | if (btrfs_test_opt(info, NOLOGREPLAY) && !(new_flags & SB_RDONLY)) { | |
867 | btrfs_err(info, | |
868 | "nologreplay must be used with ro mount option"); | |
869 | ret = -EINVAL; | |
870 | } | |
871 | out: | |
872 | if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) && | |
873 | !btrfs_test_opt(info, FREE_SPACE_TREE) && | |
874 | !btrfs_test_opt(info, CLEAR_CACHE)) { | |
875 | btrfs_err(info, "cannot disable free space tree"); | |
876 | ret = -EINVAL; | |
877 | ||
878 | } | |
879 | if (!ret && btrfs_test_opt(info, SPACE_CACHE)) | |
880 | btrfs_info(info, "disk space caching is enabled"); | |
881 | if (!ret && btrfs_test_opt(info, FREE_SPACE_TREE)) | |
882 | btrfs_info(info, "using free space tree"); | |
883 | return ret; | |
884 | } | |
885 | ||
886 | /* | |
887 | * Parse mount options that are required early in the mount process. | |
888 | * | |
889 | * All other options will be parsed on much later in the mount process and | |
890 | * only when we need to allocate a new super block. | |
891 | */ | |
892 | static int btrfs_parse_device_options(const char *options, fmode_t flags, | |
893 | void *holder) | |
894 | { | |
895 | substring_t args[MAX_OPT_ARGS]; | |
896 | char *device_name, *opts, *orig, *p; | |
897 | struct btrfs_device *device = NULL; | |
898 | int error = 0; | |
899 | ||
900 | lockdep_assert_held(&uuid_mutex); | |
901 | ||
902 | if (!options) | |
903 | return 0; | |
904 | ||
905 | /* | |
906 | * strsep changes the string, duplicate it because btrfs_parse_options | |
907 | * gets called later | |
908 | */ | |
909 | opts = kstrdup(options, GFP_KERNEL); | |
910 | if (!opts) | |
911 | return -ENOMEM; | |
912 | orig = opts; | |
913 | ||
914 | while ((p = strsep(&opts, ",")) != NULL) { | |
915 | int token; | |
916 | ||
917 | if (!*p) | |
918 | continue; | |
919 | ||
920 | token = match_token(p, tokens, args); | |
921 | if (token == Opt_device) { | |
922 | device_name = match_strdup(&args[0]); | |
923 | if (!device_name) { | |
924 | error = -ENOMEM; | |
925 | goto out; | |
926 | } | |
927 | device = btrfs_scan_one_device(device_name, flags, | |
928 | holder); | |
929 | kfree(device_name); | |
930 | if (IS_ERR(device)) { | |
931 | error = PTR_ERR(device); | |
932 | goto out; | |
933 | } | |
934 | } | |
935 | } | |
936 | ||
937 | out: | |
938 | kfree(orig); | |
939 | return error; | |
940 | } | |
941 | ||
942 | /* | |
943 | * Parse mount options that are related to subvolume id | |
944 | * | |
945 | * The value is later passed to mount_subvol() | |
946 | */ | |
947 | static int btrfs_parse_subvol_options(const char *options, char **subvol_name, | |
948 | u64 *subvol_objectid) | |
949 | { | |
950 | substring_t args[MAX_OPT_ARGS]; | |
951 | char *opts, *orig, *p; | |
952 | int error = 0; | |
953 | u64 subvolid; | |
954 | ||
955 | if (!options) | |
956 | return 0; | |
957 | ||
958 | /* | |
959 | * strsep changes the string, duplicate it because | |
960 | * btrfs_parse_device_options gets called later | |
961 | */ | |
962 | opts = kstrdup(options, GFP_KERNEL); | |
963 | if (!opts) | |
964 | return -ENOMEM; | |
965 | orig = opts; | |
966 | ||
967 | while ((p = strsep(&opts, ",")) != NULL) { | |
968 | int token; | |
969 | if (!*p) | |
970 | continue; | |
971 | ||
972 | token = match_token(p, tokens, args); | |
973 | switch (token) { | |
974 | case Opt_subvol: | |
975 | kfree(*subvol_name); | |
976 | *subvol_name = match_strdup(&args[0]); | |
977 | if (!*subvol_name) { | |
978 | error = -ENOMEM; | |
979 | goto out; | |
980 | } | |
981 | break; | |
982 | case Opt_subvolid: | |
983 | error = match_u64(&args[0], &subvolid); | |
984 | if (error) | |
985 | goto out; | |
986 | ||
987 | /* we want the original fs_tree */ | |
988 | if (subvolid == 0) | |
989 | subvolid = BTRFS_FS_TREE_OBJECTID; | |
990 | ||
991 | *subvol_objectid = subvolid; | |
992 | break; | |
993 | case Opt_subvolrootid: | |
994 | pr_warn("BTRFS: 'subvolrootid' mount option is deprecated and has no effect\n"); | |
995 | break; | |
996 | default: | |
997 | break; | |
998 | } | |
999 | } | |
1000 | ||
1001 | out: | |
1002 | kfree(orig); | |
1003 | return error; | |
1004 | } | |
1005 | ||
1006 | static char *get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info, | |
1007 | u64 subvol_objectid) | |
1008 | { | |
1009 | struct btrfs_root *root = fs_info->tree_root; | |
1010 | struct btrfs_root *fs_root; | |
1011 | struct btrfs_root_ref *root_ref; | |
1012 | struct btrfs_inode_ref *inode_ref; | |
1013 | struct btrfs_key key; | |
1014 | struct btrfs_path *path = NULL; | |
1015 | char *name = NULL, *ptr; | |
1016 | u64 dirid; | |
1017 | int len; | |
1018 | int ret; | |
1019 | ||
1020 | path = btrfs_alloc_path(); | |
1021 | if (!path) { | |
1022 | ret = -ENOMEM; | |
1023 | goto err; | |
1024 | } | |
1025 | path->leave_spinning = 1; | |
1026 | ||
1027 | name = kmalloc(PATH_MAX, GFP_KERNEL); | |
1028 | if (!name) { | |
1029 | ret = -ENOMEM; | |
1030 | goto err; | |
1031 | } | |
1032 | ptr = name + PATH_MAX - 1; | |
1033 | ptr[0] = '\0'; | |
1034 | ||
1035 | /* | |
1036 | * Walk up the subvolume trees in the tree of tree roots by root | |
1037 | * backrefs until we hit the top-level subvolume. | |
1038 | */ | |
1039 | while (subvol_objectid != BTRFS_FS_TREE_OBJECTID) { | |
1040 | key.objectid = subvol_objectid; | |
1041 | key.type = BTRFS_ROOT_BACKREF_KEY; | |
1042 | key.offset = (u64)-1; | |
1043 | ||
1044 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
1045 | if (ret < 0) { | |
1046 | goto err; | |
1047 | } else if (ret > 0) { | |
1048 | ret = btrfs_previous_item(root, path, subvol_objectid, | |
1049 | BTRFS_ROOT_BACKREF_KEY); | |
1050 | if (ret < 0) { | |
1051 | goto err; | |
1052 | } else if (ret > 0) { | |
1053 | ret = -ENOENT; | |
1054 | goto err; | |
1055 | } | |
1056 | } | |
1057 | ||
1058 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1059 | subvol_objectid = key.offset; | |
1060 | ||
1061 | root_ref = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
1062 | struct btrfs_root_ref); | |
1063 | len = btrfs_root_ref_name_len(path->nodes[0], root_ref); | |
1064 | ptr -= len + 1; | |
1065 | if (ptr < name) { | |
1066 | ret = -ENAMETOOLONG; | |
1067 | goto err; | |
1068 | } | |
1069 | read_extent_buffer(path->nodes[0], ptr + 1, | |
1070 | (unsigned long)(root_ref + 1), len); | |
1071 | ptr[0] = '/'; | |
1072 | dirid = btrfs_root_ref_dirid(path->nodes[0], root_ref); | |
1073 | btrfs_release_path(path); | |
1074 | ||
1075 | key.objectid = subvol_objectid; | |
1076 | key.type = BTRFS_ROOT_ITEM_KEY; | |
1077 | key.offset = (u64)-1; | |
1078 | fs_root = btrfs_read_fs_root_no_name(fs_info, &key); | |
1079 | if (IS_ERR(fs_root)) { | |
1080 | ret = PTR_ERR(fs_root); | |
1081 | goto err; | |
1082 | } | |
1083 | ||
1084 | /* | |
1085 | * Walk up the filesystem tree by inode refs until we hit the | |
1086 | * root directory. | |
1087 | */ | |
1088 | while (dirid != BTRFS_FIRST_FREE_OBJECTID) { | |
1089 | key.objectid = dirid; | |
1090 | key.type = BTRFS_INODE_REF_KEY; | |
1091 | key.offset = (u64)-1; | |
1092 | ||
1093 | ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0); | |
1094 | if (ret < 0) { | |
1095 | goto err; | |
1096 | } else if (ret > 0) { | |
1097 | ret = btrfs_previous_item(fs_root, path, dirid, | |
1098 | BTRFS_INODE_REF_KEY); | |
1099 | if (ret < 0) { | |
1100 | goto err; | |
1101 | } else if (ret > 0) { | |
1102 | ret = -ENOENT; | |
1103 | goto err; | |
1104 | } | |
1105 | } | |
1106 | ||
1107 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1108 | dirid = key.offset; | |
1109 | ||
1110 | inode_ref = btrfs_item_ptr(path->nodes[0], | |
1111 | path->slots[0], | |
1112 | struct btrfs_inode_ref); | |
1113 | len = btrfs_inode_ref_name_len(path->nodes[0], | |
1114 | inode_ref); | |
1115 | ptr -= len + 1; | |
1116 | if (ptr < name) { | |
1117 | ret = -ENAMETOOLONG; | |
1118 | goto err; | |
1119 | } | |
1120 | read_extent_buffer(path->nodes[0], ptr + 1, | |
1121 | (unsigned long)(inode_ref + 1), len); | |
1122 | ptr[0] = '/'; | |
1123 | btrfs_release_path(path); | |
1124 | } | |
1125 | } | |
1126 | ||
1127 | btrfs_free_path(path); | |
1128 | if (ptr == name + PATH_MAX - 1) { | |
1129 | name[0] = '/'; | |
1130 | name[1] = '\0'; | |
1131 | } else { | |
1132 | memmove(name, ptr, name + PATH_MAX - ptr); | |
1133 | } | |
1134 | return name; | |
1135 | ||
1136 | err: | |
1137 | btrfs_free_path(path); | |
1138 | kfree(name); | |
1139 | return ERR_PTR(ret); | |
1140 | } | |
1141 | ||
1142 | static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid) | |
1143 | { | |
1144 | struct btrfs_root *root = fs_info->tree_root; | |
1145 | struct btrfs_dir_item *di; | |
1146 | struct btrfs_path *path; | |
1147 | struct btrfs_key location; | |
1148 | u64 dir_id; | |
1149 | ||
1150 | path = btrfs_alloc_path(); | |
1151 | if (!path) | |
1152 | return -ENOMEM; | |
1153 | path->leave_spinning = 1; | |
1154 | ||
1155 | /* | |
1156 | * Find the "default" dir item which points to the root item that we | |
1157 | * will mount by default if we haven't been given a specific subvolume | |
1158 | * to mount. | |
1159 | */ | |
1160 | dir_id = btrfs_super_root_dir(fs_info->super_copy); | |
1161 | di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0); | |
1162 | if (IS_ERR(di)) { | |
1163 | btrfs_free_path(path); | |
1164 | return PTR_ERR(di); | |
1165 | } | |
1166 | if (!di) { | |
1167 | /* | |
1168 | * Ok the default dir item isn't there. This is weird since | |
1169 | * it's always been there, but don't freak out, just try and | |
1170 | * mount the top-level subvolume. | |
1171 | */ | |
1172 | btrfs_free_path(path); | |
1173 | *objectid = BTRFS_FS_TREE_OBJECTID; | |
1174 | return 0; | |
1175 | } | |
1176 | ||
1177 | btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location); | |
1178 | btrfs_free_path(path); | |
1179 | *objectid = location.objectid; | |
1180 | return 0; | |
1181 | } | |
1182 | ||
1183 | static int btrfs_fill_super(struct super_block *sb, | |
1184 | struct btrfs_fs_devices *fs_devices, | |
1185 | void *data) | |
1186 | { | |
1187 | struct inode *inode; | |
1188 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
1189 | struct btrfs_key key; | |
1190 | int err; | |
1191 | ||
1192 | sb->s_maxbytes = MAX_LFS_FILESIZE; | |
1193 | sb->s_magic = BTRFS_SUPER_MAGIC; | |
1194 | sb->s_op = &btrfs_super_ops; | |
1195 | sb->s_d_op = &btrfs_dentry_operations; | |
1196 | sb->s_export_op = &btrfs_export_ops; | |
1197 | sb->s_xattr = btrfs_xattr_handlers; | |
1198 | sb->s_time_gran = 1; | |
1199 | #ifdef CONFIG_BTRFS_FS_POSIX_ACL | |
1200 | sb->s_flags |= SB_POSIXACL; | |
1201 | #endif | |
1202 | sb->s_flags |= SB_I_VERSION; | |
1203 | sb->s_iflags |= SB_I_CGROUPWB; | |
1204 | ||
1205 | err = super_setup_bdi(sb); | |
1206 | if (err) { | |
1207 | btrfs_err(fs_info, "super_setup_bdi failed"); | |
1208 | return err; | |
1209 | } | |
1210 | ||
1211 | err = open_ctree(sb, fs_devices, (char *)data); | |
1212 | if (err) { | |
1213 | btrfs_err(fs_info, "open_ctree failed"); | |
1214 | return err; | |
1215 | } | |
1216 | ||
1217 | key.objectid = BTRFS_FIRST_FREE_OBJECTID; | |
1218 | key.type = BTRFS_INODE_ITEM_KEY; | |
1219 | key.offset = 0; | |
1220 | inode = btrfs_iget(sb, &key, fs_info->fs_root, NULL); | |
1221 | if (IS_ERR(inode)) { | |
1222 | err = PTR_ERR(inode); | |
1223 | goto fail_close; | |
1224 | } | |
1225 | ||
1226 | sb->s_root = d_make_root(inode); | |
1227 | if (!sb->s_root) { | |
1228 | err = -ENOMEM; | |
1229 | goto fail_close; | |
1230 | } | |
1231 | ||
1232 | cleancache_init_fs(sb); | |
1233 | sb->s_flags |= SB_ACTIVE; | |
1234 | return 0; | |
1235 | ||
1236 | fail_close: | |
1237 | close_ctree(fs_info); | |
1238 | return err; | |
1239 | } | |
1240 | ||
1241 | int btrfs_sync_fs(struct super_block *sb, int wait) | |
1242 | { | |
1243 | struct btrfs_trans_handle *trans; | |
1244 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
1245 | struct btrfs_root *root = fs_info->tree_root; | |
1246 | ||
1247 | trace_btrfs_sync_fs(fs_info, wait); | |
1248 | ||
1249 | if (!wait) { | |
1250 | filemap_flush(fs_info->btree_inode->i_mapping); | |
1251 | return 0; | |
1252 | } | |
1253 | ||
1254 | btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1); | |
1255 | ||
1256 | trans = btrfs_attach_transaction_barrier(root); | |
1257 | if (IS_ERR(trans)) { | |
1258 | /* no transaction, don't bother */ | |
1259 | if (PTR_ERR(trans) == -ENOENT) { | |
1260 | /* | |
1261 | * Exit unless we have some pending changes | |
1262 | * that need to go through commit | |
1263 | */ | |
1264 | if (fs_info->pending_changes == 0) | |
1265 | return 0; | |
1266 | /* | |
1267 | * A non-blocking test if the fs is frozen. We must not | |
1268 | * start a new transaction here otherwise a deadlock | |
1269 | * happens. The pending operations are delayed to the | |
1270 | * next commit after thawing. | |
1271 | */ | |
1272 | if (sb_start_write_trylock(sb)) | |
1273 | sb_end_write(sb); | |
1274 | else | |
1275 | return 0; | |
1276 | trans = btrfs_start_transaction(root, 0); | |
1277 | } | |
1278 | if (IS_ERR(trans)) | |
1279 | return PTR_ERR(trans); | |
1280 | } | |
1281 | return btrfs_commit_transaction(trans); | |
1282 | } | |
1283 | ||
1284 | static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) | |
1285 | { | |
1286 | struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb); | |
1287 | const char *compress_type; | |
1288 | ||
1289 | if (btrfs_test_opt(info, DEGRADED)) | |
1290 | seq_puts(seq, ",degraded"); | |
1291 | if (btrfs_test_opt(info, NODATASUM)) | |
1292 | seq_puts(seq, ",nodatasum"); | |
1293 | if (btrfs_test_opt(info, NODATACOW)) | |
1294 | seq_puts(seq, ",nodatacow"); | |
1295 | if (btrfs_test_opt(info, NOBARRIER)) | |
1296 | seq_puts(seq, ",nobarrier"); | |
1297 | if (info->max_inline != BTRFS_DEFAULT_MAX_INLINE) | |
1298 | seq_printf(seq, ",max_inline=%llu", info->max_inline); | |
1299 | if (info->thread_pool_size != min_t(unsigned long, | |
1300 | num_online_cpus() + 2, 8)) | |
1301 | seq_printf(seq, ",thread_pool=%u", info->thread_pool_size); | |
1302 | if (btrfs_test_opt(info, COMPRESS)) { | |
1303 | compress_type = btrfs_compress_type2str(info->compress_type); | |
1304 | if (btrfs_test_opt(info, FORCE_COMPRESS)) | |
1305 | seq_printf(seq, ",compress-force=%s", compress_type); | |
1306 | else | |
1307 | seq_printf(seq, ",compress=%s", compress_type); | |
1308 | if (info->compress_level) | |
1309 | seq_printf(seq, ":%d", info->compress_level); | |
1310 | } | |
1311 | if (btrfs_test_opt(info, NOSSD)) | |
1312 | seq_puts(seq, ",nossd"); | |
1313 | if (btrfs_test_opt(info, SSD_SPREAD)) | |
1314 | seq_puts(seq, ",ssd_spread"); | |
1315 | else if (btrfs_test_opt(info, SSD)) | |
1316 | seq_puts(seq, ",ssd"); | |
1317 | if (btrfs_test_opt(info, NOTREELOG)) | |
1318 | seq_puts(seq, ",notreelog"); | |
1319 | if (btrfs_test_opt(info, NOLOGREPLAY)) | |
1320 | seq_puts(seq, ",nologreplay"); | |
1321 | if (btrfs_test_opt(info, FLUSHONCOMMIT)) | |
1322 | seq_puts(seq, ",flushoncommit"); | |
1323 | if (btrfs_test_opt(info, DISCARD)) | |
1324 | seq_puts(seq, ",discard"); | |
1325 | if (!(info->sb->s_flags & SB_POSIXACL)) | |
1326 | seq_puts(seq, ",noacl"); | |
1327 | if (btrfs_test_opt(info, SPACE_CACHE)) | |
1328 | seq_puts(seq, ",space_cache"); | |
1329 | else if (btrfs_test_opt(info, FREE_SPACE_TREE)) | |
1330 | seq_puts(seq, ",space_cache=v2"); | |
1331 | else | |
1332 | seq_puts(seq, ",nospace_cache"); | |
1333 | if (btrfs_test_opt(info, RESCAN_UUID_TREE)) | |
1334 | seq_puts(seq, ",rescan_uuid_tree"); | |
1335 | if (btrfs_test_opt(info, CLEAR_CACHE)) | |
1336 | seq_puts(seq, ",clear_cache"); | |
1337 | if (btrfs_test_opt(info, USER_SUBVOL_RM_ALLOWED)) | |
1338 | seq_puts(seq, ",user_subvol_rm_allowed"); | |
1339 | if (btrfs_test_opt(info, ENOSPC_DEBUG)) | |
1340 | seq_puts(seq, ",enospc_debug"); | |
1341 | if (btrfs_test_opt(info, AUTO_DEFRAG)) | |
1342 | seq_puts(seq, ",autodefrag"); | |
1343 | if (btrfs_test_opt(info, INODE_MAP_CACHE)) | |
1344 | seq_puts(seq, ",inode_cache"); | |
1345 | if (btrfs_test_opt(info, SKIP_BALANCE)) | |
1346 | seq_puts(seq, ",skip_balance"); | |
1347 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY | |
1348 | if (btrfs_test_opt(info, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA)) | |
1349 | seq_puts(seq, ",check_int_data"); | |
1350 | else if (btrfs_test_opt(info, CHECK_INTEGRITY)) | |
1351 | seq_puts(seq, ",check_int"); | |
1352 | if (info->check_integrity_print_mask) | |
1353 | seq_printf(seq, ",check_int_print_mask=%d", | |
1354 | info->check_integrity_print_mask); | |
1355 | #endif | |
1356 | if (info->metadata_ratio) | |
1357 | seq_printf(seq, ",metadata_ratio=%u", info->metadata_ratio); | |
1358 | if (btrfs_test_opt(info, PANIC_ON_FATAL_ERROR)) | |
1359 | seq_puts(seq, ",fatal_errors=panic"); | |
1360 | if (info->commit_interval != BTRFS_DEFAULT_COMMIT_INTERVAL) | |
1361 | seq_printf(seq, ",commit=%u", info->commit_interval); | |
1362 | #ifdef CONFIG_BTRFS_DEBUG | |
1363 | if (btrfs_test_opt(info, FRAGMENT_DATA)) | |
1364 | seq_puts(seq, ",fragment=data"); | |
1365 | if (btrfs_test_opt(info, FRAGMENT_METADATA)) | |
1366 | seq_puts(seq, ",fragment=metadata"); | |
1367 | #endif | |
1368 | if (btrfs_test_opt(info, REF_VERIFY)) | |
1369 | seq_puts(seq, ",ref_verify"); | |
1370 | seq_printf(seq, ",subvolid=%llu", | |
1371 | BTRFS_I(d_inode(dentry))->root->root_key.objectid); | |
1372 | seq_puts(seq, ",subvol="); | |
1373 | seq_dentry(seq, dentry, " \t\n\\"); | |
1374 | return 0; | |
1375 | } | |
1376 | ||
1377 | static int btrfs_test_super(struct super_block *s, void *data) | |
1378 | { | |
1379 | struct btrfs_fs_info *p = data; | |
1380 | struct btrfs_fs_info *fs_info = btrfs_sb(s); | |
1381 | ||
1382 | return fs_info->fs_devices == p->fs_devices; | |
1383 | } | |
1384 | ||
1385 | static int btrfs_set_super(struct super_block *s, void *data) | |
1386 | { | |
1387 | int err = set_anon_super(s, data); | |
1388 | if (!err) | |
1389 | s->s_fs_info = data; | |
1390 | return err; | |
1391 | } | |
1392 | ||
1393 | /* | |
1394 | * subvolumes are identified by ino 256 | |
1395 | */ | |
1396 | static inline int is_subvolume_inode(struct inode *inode) | |
1397 | { | |
1398 | if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID) | |
1399 | return 1; | |
1400 | return 0; | |
1401 | } | |
1402 | ||
1403 | static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid, | |
1404 | struct vfsmount *mnt) | |
1405 | { | |
1406 | struct dentry *root; | |
1407 | int ret; | |
1408 | ||
1409 | if (!subvol_name) { | |
1410 | if (!subvol_objectid) { | |
1411 | ret = get_default_subvol_objectid(btrfs_sb(mnt->mnt_sb), | |
1412 | &subvol_objectid); | |
1413 | if (ret) { | |
1414 | root = ERR_PTR(ret); | |
1415 | goto out; | |
1416 | } | |
1417 | } | |
1418 | subvol_name = get_subvol_name_from_objectid(btrfs_sb(mnt->mnt_sb), | |
1419 | subvol_objectid); | |
1420 | if (IS_ERR(subvol_name)) { | |
1421 | root = ERR_CAST(subvol_name); | |
1422 | subvol_name = NULL; | |
1423 | goto out; | |
1424 | } | |
1425 | ||
1426 | } | |
1427 | ||
1428 | root = mount_subtree(mnt, subvol_name); | |
1429 | /* mount_subtree() drops our reference on the vfsmount. */ | |
1430 | mnt = NULL; | |
1431 | ||
1432 | if (!IS_ERR(root)) { | |
1433 | struct super_block *s = root->d_sb; | |
1434 | struct btrfs_fs_info *fs_info = btrfs_sb(s); | |
1435 | struct inode *root_inode = d_inode(root); | |
1436 | u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid; | |
1437 | ||
1438 | ret = 0; | |
1439 | if (!is_subvolume_inode(root_inode)) { | |
1440 | btrfs_err(fs_info, "'%s' is not a valid subvolume", | |
1441 | subvol_name); | |
1442 | ret = -EINVAL; | |
1443 | } | |
1444 | if (subvol_objectid && root_objectid != subvol_objectid) { | |
1445 | /* | |
1446 | * This will also catch a race condition where a | |
1447 | * subvolume which was passed by ID is renamed and | |
1448 | * another subvolume is renamed over the old location. | |
1449 | */ | |
1450 | btrfs_err(fs_info, | |
1451 | "subvol '%s' does not match subvolid %llu", | |
1452 | subvol_name, subvol_objectid); | |
1453 | ret = -EINVAL; | |
1454 | } | |
1455 | if (ret) { | |
1456 | dput(root); | |
1457 | root = ERR_PTR(ret); | |
1458 | deactivate_locked_super(s); | |
1459 | } | |
1460 | } | |
1461 | ||
1462 | out: | |
1463 | mntput(mnt); | |
1464 | kfree(subvol_name); | |
1465 | return root; | |
1466 | } | |
1467 | ||
1468 | /* | |
1469 | * Find a superblock for the given device / mount point. | |
1470 | * | |
1471 | * Note: This is based on mount_bdev from fs/super.c with a few additions | |
1472 | * for multiple device setup. Make sure to keep it in sync. | |
1473 | */ | |
1474 | static struct dentry *btrfs_mount_root(struct file_system_type *fs_type, | |
1475 | int flags, const char *device_name, void *data) | |
1476 | { | |
1477 | struct block_device *bdev = NULL; | |
1478 | struct super_block *s; | |
1479 | struct btrfs_device *device = NULL; | |
1480 | struct btrfs_fs_devices *fs_devices = NULL; | |
1481 | struct btrfs_fs_info *fs_info = NULL; | |
1482 | void *new_sec_opts = NULL; | |
1483 | fmode_t mode = FMODE_READ; | |
1484 | int error = 0; | |
1485 | ||
1486 | if (!(flags & SB_RDONLY)) | |
1487 | mode |= FMODE_WRITE; | |
1488 | ||
1489 | if (data) { | |
1490 | error = security_sb_eat_lsm_opts(data, &new_sec_opts); | |
1491 | if (error) | |
1492 | return ERR_PTR(error); | |
1493 | } | |
1494 | ||
1495 | /* | |
1496 | * Setup a dummy root and fs_info for test/set super. This is because | |
1497 | * we don't actually fill this stuff out until open_ctree, but we need | |
1498 | * it for searching for existing supers, so this lets us do that and | |
1499 | * then open_ctree will properly initialize everything later. | |
1500 | */ | |
1501 | fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL); | |
1502 | if (!fs_info) { | |
1503 | error = -ENOMEM; | |
1504 | goto error_sec_opts; | |
1505 | } | |
1506 | ||
1507 | fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); | |
1508 | fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL); | |
1509 | if (!fs_info->super_copy || !fs_info->super_for_commit) { | |
1510 | error = -ENOMEM; | |
1511 | goto error_fs_info; | |
1512 | } | |
1513 | ||
1514 | mutex_lock(&uuid_mutex); | |
1515 | error = btrfs_parse_device_options(data, mode, fs_type); | |
1516 | if (error) { | |
1517 | mutex_unlock(&uuid_mutex); | |
1518 | goto error_fs_info; | |
1519 | } | |
1520 | ||
1521 | device = btrfs_scan_one_device(device_name, mode, fs_type); | |
1522 | if (IS_ERR(device)) { | |
1523 | mutex_unlock(&uuid_mutex); | |
1524 | error = PTR_ERR(device); | |
1525 | goto error_fs_info; | |
1526 | } | |
1527 | ||
1528 | fs_devices = device->fs_devices; | |
1529 | fs_info->fs_devices = fs_devices; | |
1530 | ||
1531 | error = btrfs_open_devices(fs_devices, mode, fs_type); | |
1532 | mutex_unlock(&uuid_mutex); | |
1533 | if (error) | |
1534 | goto error_fs_info; | |
1535 | ||
1536 | if (!(flags & SB_RDONLY) && fs_devices->rw_devices == 0) { | |
1537 | error = -EACCES; | |
1538 | goto error_close_devices; | |
1539 | } | |
1540 | ||
1541 | bdev = fs_devices->latest_bdev; | |
1542 | s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | SB_NOSEC, | |
1543 | fs_info); | |
1544 | if (IS_ERR(s)) { | |
1545 | error = PTR_ERR(s); | |
1546 | goto error_close_devices; | |
1547 | } | |
1548 | ||
1549 | if (s->s_root) { | |
1550 | btrfs_close_devices(fs_devices); | |
1551 | free_fs_info(fs_info); | |
1552 | if ((flags ^ s->s_flags) & SB_RDONLY) | |
1553 | error = -EBUSY; | |
1554 | } else { | |
1555 | snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev); | |
1556 | btrfs_sb(s)->bdev_holder = fs_type; | |
1557 | if (!strstr(crc32c_impl(), "generic")) | |
1558 | set_bit(BTRFS_FS_CSUM_IMPL_FAST, &fs_info->flags); | |
1559 | error = btrfs_fill_super(s, fs_devices, data); | |
1560 | } | |
1561 | if (!error) | |
1562 | error = security_sb_set_mnt_opts(s, new_sec_opts, 0, NULL); | |
1563 | security_free_mnt_opts(&new_sec_opts); | |
1564 | if (error) { | |
1565 | deactivate_locked_super(s); | |
1566 | return ERR_PTR(error); | |
1567 | } | |
1568 | ||
1569 | return dget(s->s_root); | |
1570 | ||
1571 | error_close_devices: | |
1572 | btrfs_close_devices(fs_devices); | |
1573 | error_fs_info: | |
1574 | free_fs_info(fs_info); | |
1575 | error_sec_opts: | |
1576 | security_free_mnt_opts(&new_sec_opts); | |
1577 | return ERR_PTR(error); | |
1578 | } | |
1579 | ||
1580 | /* | |
1581 | * Mount function which is called by VFS layer. | |
1582 | * | |
1583 | * In order to allow mounting a subvolume directly, btrfs uses mount_subtree() | |
1584 | * which needs vfsmount* of device's root (/). This means device's root has to | |
1585 | * be mounted internally in any case. | |
1586 | * | |
1587 | * Operation flow: | |
1588 | * 1. Parse subvol id related options for later use in mount_subvol(). | |
1589 | * | |
1590 | * 2. Mount device's root (/) by calling vfs_kern_mount(). | |
1591 | * | |
1592 | * NOTE: vfs_kern_mount() is used by VFS to call btrfs_mount() in the | |
1593 | * first place. In order to avoid calling btrfs_mount() again, we use | |
1594 | * different file_system_type which is not registered to VFS by | |
1595 | * register_filesystem() (btrfs_root_fs_type). As a result, | |
1596 | * btrfs_mount_root() is called. The return value will be used by | |
1597 | * mount_subtree() in mount_subvol(). | |
1598 | * | |
1599 | * 3. Call mount_subvol() to get the dentry of subvolume. Since there is | |
1600 | * "btrfs subvolume set-default", mount_subvol() is called always. | |
1601 | */ | |
1602 | static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags, | |
1603 | const char *device_name, void *data) | |
1604 | { | |
1605 | struct vfsmount *mnt_root; | |
1606 | struct dentry *root; | |
1607 | char *subvol_name = NULL; | |
1608 | u64 subvol_objectid = 0; | |
1609 | int error = 0; | |
1610 | ||
1611 | error = btrfs_parse_subvol_options(data, &subvol_name, | |
1612 | &subvol_objectid); | |
1613 | if (error) { | |
1614 | kfree(subvol_name); | |
1615 | return ERR_PTR(error); | |
1616 | } | |
1617 | ||
1618 | /* mount device's root (/) */ | |
1619 | mnt_root = vfs_kern_mount(&btrfs_root_fs_type, flags, device_name, data); | |
1620 | if (PTR_ERR_OR_ZERO(mnt_root) == -EBUSY) { | |
1621 | if (flags & SB_RDONLY) { | |
1622 | mnt_root = vfs_kern_mount(&btrfs_root_fs_type, | |
1623 | flags & ~SB_RDONLY, device_name, data); | |
1624 | } else { | |
1625 | mnt_root = vfs_kern_mount(&btrfs_root_fs_type, | |
1626 | flags | SB_RDONLY, device_name, data); | |
1627 | if (IS_ERR(mnt_root)) { | |
1628 | root = ERR_CAST(mnt_root); | |
1629 | kfree(subvol_name); | |
1630 | goto out; | |
1631 | } | |
1632 | ||
1633 | down_write(&mnt_root->mnt_sb->s_umount); | |
1634 | error = btrfs_remount(mnt_root->mnt_sb, &flags, NULL); | |
1635 | up_write(&mnt_root->mnt_sb->s_umount); | |
1636 | if (error < 0) { | |
1637 | root = ERR_PTR(error); | |
1638 | mntput(mnt_root); | |
1639 | kfree(subvol_name); | |
1640 | goto out; | |
1641 | } | |
1642 | } | |
1643 | } | |
1644 | if (IS_ERR(mnt_root)) { | |
1645 | root = ERR_CAST(mnt_root); | |
1646 | kfree(subvol_name); | |
1647 | goto out; | |
1648 | } | |
1649 | ||
1650 | /* mount_subvol() will free subvol_name and mnt_root */ | |
1651 | root = mount_subvol(subvol_name, subvol_objectid, mnt_root); | |
1652 | ||
1653 | out: | |
1654 | return root; | |
1655 | } | |
1656 | ||
1657 | static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info, | |
1658 | u32 new_pool_size, u32 old_pool_size) | |
1659 | { | |
1660 | if (new_pool_size == old_pool_size) | |
1661 | return; | |
1662 | ||
1663 | fs_info->thread_pool_size = new_pool_size; | |
1664 | ||
1665 | btrfs_info(fs_info, "resize thread pool %d -> %d", | |
1666 | old_pool_size, new_pool_size); | |
1667 | ||
1668 | btrfs_workqueue_set_max(fs_info->workers, new_pool_size); | |
1669 | btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size); | |
1670 | btrfs_workqueue_set_max(fs_info->submit_workers, new_pool_size); | |
1671 | btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size); | |
1672 | btrfs_workqueue_set_max(fs_info->endio_workers, new_pool_size); | |
1673 | btrfs_workqueue_set_max(fs_info->endio_meta_workers, new_pool_size); | |
1674 | btrfs_workqueue_set_max(fs_info->endio_meta_write_workers, | |
1675 | new_pool_size); | |
1676 | btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size); | |
1677 | btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size); | |
1678 | btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size); | |
1679 | btrfs_workqueue_set_max(fs_info->readahead_workers, new_pool_size); | |
1680 | btrfs_workqueue_set_max(fs_info->scrub_wr_completion_workers, | |
1681 | new_pool_size); | |
1682 | } | |
1683 | ||
1684 | static inline void btrfs_remount_prepare(struct btrfs_fs_info *fs_info) | |
1685 | { | |
1686 | set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); | |
1687 | } | |
1688 | ||
1689 | static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info, | |
1690 | unsigned long old_opts, int flags) | |
1691 | { | |
1692 | if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && | |
1693 | (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || | |
1694 | (flags & SB_RDONLY))) { | |
1695 | /* wait for any defraggers to finish */ | |
1696 | wait_event(fs_info->transaction_wait, | |
1697 | (atomic_read(&fs_info->defrag_running) == 0)); | |
1698 | if (flags & SB_RDONLY) | |
1699 | sync_filesystem(fs_info->sb); | |
1700 | } | |
1701 | } | |
1702 | ||
1703 | static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info, | |
1704 | unsigned long old_opts) | |
1705 | { | |
1706 | /* | |
1707 | * We need to cleanup all defragable inodes if the autodefragment is | |
1708 | * close or the filesystem is read only. | |
1709 | */ | |
1710 | if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) && | |
1711 | (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || sb_rdonly(fs_info->sb))) { | |
1712 | btrfs_cleanup_defrag_inodes(fs_info); | |
1713 | } | |
1714 | ||
1715 | clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state); | |
1716 | } | |
1717 | ||
1718 | static int btrfs_remount(struct super_block *sb, int *flags, char *data) | |
1719 | { | |
1720 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
1721 | struct btrfs_root *root = fs_info->tree_root; | |
1722 | unsigned old_flags = sb->s_flags; | |
1723 | unsigned long old_opts = fs_info->mount_opt; | |
1724 | unsigned long old_compress_type = fs_info->compress_type; | |
1725 | u64 old_max_inline = fs_info->max_inline; | |
1726 | u32 old_thread_pool_size = fs_info->thread_pool_size; | |
1727 | u32 old_metadata_ratio = fs_info->metadata_ratio; | |
1728 | int ret; | |
1729 | ||
1730 | sync_filesystem(sb); | |
1731 | btrfs_remount_prepare(fs_info); | |
1732 | ||
1733 | if (data) { | |
1734 | void *new_sec_opts = NULL; | |
1735 | ||
1736 | ret = security_sb_eat_lsm_opts(data, &new_sec_opts); | |
1737 | if (!ret) | |
1738 | ret = security_sb_remount(sb, new_sec_opts); | |
1739 | security_free_mnt_opts(&new_sec_opts); | |
1740 | if (ret) | |
1741 | goto restore; | |
1742 | } | |
1743 | ||
1744 | ret = btrfs_parse_options(fs_info, data, *flags); | |
1745 | if (ret) | |
1746 | goto restore; | |
1747 | ||
1748 | btrfs_remount_begin(fs_info, old_opts, *flags); | |
1749 | btrfs_resize_thread_pool(fs_info, | |
1750 | fs_info->thread_pool_size, old_thread_pool_size); | |
1751 | ||
1752 | if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb)) | |
1753 | goto out; | |
1754 | ||
1755 | if (*flags & SB_RDONLY) { | |
1756 | /* | |
1757 | * this also happens on 'umount -rf' or on shutdown, when | |
1758 | * the filesystem is busy. | |
1759 | */ | |
1760 | cancel_work_sync(&fs_info->async_reclaim_work); | |
1761 | ||
1762 | /* wait for the uuid_scan task to finish */ | |
1763 | down(&fs_info->uuid_tree_rescan_sem); | |
1764 | /* avoid complains from lockdep et al. */ | |
1765 | up(&fs_info->uuid_tree_rescan_sem); | |
1766 | ||
1767 | sb->s_flags |= SB_RDONLY; | |
1768 | ||
1769 | /* | |
1770 | * Setting SB_RDONLY will put the cleaner thread to | |
1771 | * sleep at the next loop if it's already active. | |
1772 | * If it's already asleep, we'll leave unused block | |
1773 | * groups on disk until we're mounted read-write again | |
1774 | * unless we clean them up here. | |
1775 | */ | |
1776 | btrfs_delete_unused_bgs(fs_info); | |
1777 | ||
1778 | btrfs_dev_replace_suspend_for_unmount(fs_info); | |
1779 | btrfs_scrub_cancel(fs_info); | |
1780 | btrfs_pause_balance(fs_info); | |
1781 | ||
1782 | ret = btrfs_commit_super(fs_info); | |
1783 | if (ret) | |
1784 | goto restore; | |
1785 | } else { | |
1786 | if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) { | |
1787 | btrfs_err(fs_info, | |
1788 | "Remounting read-write after error is not allowed"); | |
1789 | ret = -EINVAL; | |
1790 | goto restore; | |
1791 | } | |
1792 | if (fs_info->fs_devices->rw_devices == 0) { | |
1793 | ret = -EACCES; | |
1794 | goto restore; | |
1795 | } | |
1796 | ||
1797 | if (!btrfs_check_rw_degradable(fs_info, NULL)) { | |
1798 | btrfs_warn(fs_info, | |
1799 | "too many missing devices, writable remount is not allowed"); | |
1800 | ret = -EACCES; | |
1801 | goto restore; | |
1802 | } | |
1803 | ||
1804 | if (btrfs_super_log_root(fs_info->super_copy) != 0) { | |
1805 | ret = -EINVAL; | |
1806 | goto restore; | |
1807 | } | |
1808 | ||
1809 | ret = btrfs_cleanup_fs_roots(fs_info); | |
1810 | if (ret) | |
1811 | goto restore; | |
1812 | ||
1813 | /* recover relocation */ | |
1814 | mutex_lock(&fs_info->cleaner_mutex); | |
1815 | ret = btrfs_recover_relocation(root); | |
1816 | mutex_unlock(&fs_info->cleaner_mutex); | |
1817 | if (ret) | |
1818 | goto restore; | |
1819 | ||
1820 | ret = btrfs_resume_balance_async(fs_info); | |
1821 | if (ret) | |
1822 | goto restore; | |
1823 | ||
1824 | ret = btrfs_resume_dev_replace_async(fs_info); | |
1825 | if (ret) { | |
1826 | btrfs_warn(fs_info, "failed to resume dev_replace"); | |
1827 | goto restore; | |
1828 | } | |
1829 | ||
1830 | btrfs_qgroup_rescan_resume(fs_info); | |
1831 | ||
1832 | if (!fs_info->uuid_root) { | |
1833 | btrfs_info(fs_info, "creating UUID tree"); | |
1834 | ret = btrfs_create_uuid_tree(fs_info); | |
1835 | if (ret) { | |
1836 | btrfs_warn(fs_info, | |
1837 | "failed to create the UUID tree %d", | |
1838 | ret); | |
1839 | goto restore; | |
1840 | } | |
1841 | } | |
1842 | sb->s_flags &= ~SB_RDONLY; | |
1843 | ||
1844 | set_bit(BTRFS_FS_OPEN, &fs_info->flags); | |
1845 | } | |
1846 | out: | |
1847 | wake_up_process(fs_info->transaction_kthread); | |
1848 | btrfs_remount_cleanup(fs_info, old_opts); | |
1849 | return 0; | |
1850 | ||
1851 | restore: | |
1852 | /* We've hit an error - don't reset SB_RDONLY */ | |
1853 | if (sb_rdonly(sb)) | |
1854 | old_flags |= SB_RDONLY; | |
1855 | sb->s_flags = old_flags; | |
1856 | fs_info->mount_opt = old_opts; | |
1857 | fs_info->compress_type = old_compress_type; | |
1858 | fs_info->max_inline = old_max_inline; | |
1859 | btrfs_resize_thread_pool(fs_info, | |
1860 | old_thread_pool_size, fs_info->thread_pool_size); | |
1861 | fs_info->metadata_ratio = old_metadata_ratio; | |
1862 | btrfs_remount_cleanup(fs_info, old_opts); | |
1863 | return ret; | |
1864 | } | |
1865 | ||
1866 | /* Used to sort the devices by max_avail(descending sort) */ | |
1867 | static inline int btrfs_cmp_device_free_bytes(const void *dev_info1, | |
1868 | const void *dev_info2) | |
1869 | { | |
1870 | if (((struct btrfs_device_info *)dev_info1)->max_avail > | |
1871 | ((struct btrfs_device_info *)dev_info2)->max_avail) | |
1872 | return -1; | |
1873 | else if (((struct btrfs_device_info *)dev_info1)->max_avail < | |
1874 | ((struct btrfs_device_info *)dev_info2)->max_avail) | |
1875 | return 1; | |
1876 | else | |
1877 | return 0; | |
1878 | } | |
1879 | ||
1880 | /* | |
1881 | * sort the devices by max_avail, in which max free extent size of each device | |
1882 | * is stored.(Descending Sort) | |
1883 | */ | |
1884 | static inline void btrfs_descending_sort_devices( | |
1885 | struct btrfs_device_info *devices, | |
1886 | size_t nr_devices) | |
1887 | { | |
1888 | sort(devices, nr_devices, sizeof(struct btrfs_device_info), | |
1889 | btrfs_cmp_device_free_bytes, NULL); | |
1890 | } | |
1891 | ||
1892 | /* | |
1893 | * The helper to calc the free space on the devices that can be used to store | |
1894 | * file data. | |
1895 | */ | |
1896 | static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info, | |
1897 | u64 *free_bytes) | |
1898 | { | |
1899 | struct btrfs_device_info *devices_info; | |
1900 | struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; | |
1901 | struct btrfs_device *device; | |
1902 | u64 skip_space; | |
1903 | u64 type; | |
1904 | u64 avail_space; | |
1905 | u64 min_stripe_size; | |
1906 | int min_stripes, num_stripes = 1; | |
1907 | int i = 0, nr_devices; | |
1908 | const struct btrfs_raid_attr *rattr; | |
1909 | ||
1910 | /* | |
1911 | * We aren't under the device list lock, so this is racy-ish, but good | |
1912 | * enough for our purposes. | |
1913 | */ | |
1914 | nr_devices = fs_info->fs_devices->open_devices; | |
1915 | if (!nr_devices) { | |
1916 | smp_mb(); | |
1917 | nr_devices = fs_info->fs_devices->open_devices; | |
1918 | ASSERT(nr_devices); | |
1919 | if (!nr_devices) { | |
1920 | *free_bytes = 0; | |
1921 | return 0; | |
1922 | } | |
1923 | } | |
1924 | ||
1925 | devices_info = kmalloc_array(nr_devices, sizeof(*devices_info), | |
1926 | GFP_KERNEL); | |
1927 | if (!devices_info) | |
1928 | return -ENOMEM; | |
1929 | ||
1930 | /* calc min stripe number for data space allocation */ | |
1931 | type = btrfs_data_alloc_profile(fs_info); | |
1932 | rattr = &btrfs_raid_array[btrfs_bg_flags_to_raid_index(type)]; | |
1933 | min_stripes = rattr->devs_min; | |
1934 | ||
1935 | if (type & BTRFS_BLOCK_GROUP_RAID0) | |
1936 | num_stripes = nr_devices; | |
1937 | else if (type & BTRFS_BLOCK_GROUP_RAID1) | |
1938 | num_stripes = 2; | |
1939 | else if (type & BTRFS_BLOCK_GROUP_RAID10) | |
1940 | num_stripes = 4; | |
1941 | ||
1942 | /* Adjust for more than 1 stripe per device */ | |
1943 | min_stripe_size = rattr->dev_stripes * BTRFS_STRIPE_LEN; | |
1944 | ||
1945 | rcu_read_lock(); | |
1946 | list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) { | |
1947 | if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, | |
1948 | &device->dev_state) || | |
1949 | !device->bdev || | |
1950 | test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) | |
1951 | continue; | |
1952 | ||
1953 | if (i >= nr_devices) | |
1954 | break; | |
1955 | ||
1956 | avail_space = device->total_bytes - device->bytes_used; | |
1957 | ||
1958 | /* align with stripe_len */ | |
1959 | avail_space = div_u64(avail_space, BTRFS_STRIPE_LEN); | |
1960 | avail_space *= BTRFS_STRIPE_LEN; | |
1961 | ||
1962 | /* | |
1963 | * In order to avoid overwriting the superblock on the drive, | |
1964 | * btrfs starts at an offset of at least 1MB when doing chunk | |
1965 | * allocation. | |
1966 | */ | |
1967 | skip_space = SZ_1M; | |
1968 | ||
1969 | /* | |
1970 | * we can use the free space in [0, skip_space - 1], subtract | |
1971 | * it from the total. | |
1972 | */ | |
1973 | if (avail_space && avail_space >= skip_space) | |
1974 | avail_space -= skip_space; | |
1975 | else | |
1976 | avail_space = 0; | |
1977 | ||
1978 | if (avail_space < min_stripe_size) | |
1979 | continue; | |
1980 | ||
1981 | devices_info[i].dev = device; | |
1982 | devices_info[i].max_avail = avail_space; | |
1983 | ||
1984 | i++; | |
1985 | } | |
1986 | rcu_read_unlock(); | |
1987 | ||
1988 | nr_devices = i; | |
1989 | ||
1990 | btrfs_descending_sort_devices(devices_info, nr_devices); | |
1991 | ||
1992 | i = nr_devices - 1; | |
1993 | avail_space = 0; | |
1994 | while (nr_devices >= min_stripes) { | |
1995 | if (num_stripes > nr_devices) | |
1996 | num_stripes = nr_devices; | |
1997 | ||
1998 | if (devices_info[i].max_avail >= min_stripe_size) { | |
1999 | int j; | |
2000 | u64 alloc_size; | |
2001 | ||
2002 | avail_space += devices_info[i].max_avail * num_stripes; | |
2003 | alloc_size = devices_info[i].max_avail; | |
2004 | for (j = i + 1 - num_stripes; j <= i; j++) | |
2005 | devices_info[j].max_avail -= alloc_size; | |
2006 | } | |
2007 | i--; | |
2008 | nr_devices--; | |
2009 | } | |
2010 | ||
2011 | kfree(devices_info); | |
2012 | *free_bytes = avail_space; | |
2013 | return 0; | |
2014 | } | |
2015 | ||
2016 | /* | |
2017 | * Calculate numbers for 'df', pessimistic in case of mixed raid profiles. | |
2018 | * | |
2019 | * If there's a redundant raid level at DATA block groups, use the respective | |
2020 | * multiplier to scale the sizes. | |
2021 | * | |
2022 | * Unused device space usage is based on simulating the chunk allocator | |
2023 | * algorithm that respects the device sizes and order of allocations. This is | |
2024 | * a close approximation of the actual use but there are other factors that may | |
2025 | * change the result (like a new metadata chunk). | |
2026 | * | |
2027 | * If metadata is exhausted, f_bavail will be 0. | |
2028 | */ | |
2029 | static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf) | |
2030 | { | |
2031 | struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb); | |
2032 | struct btrfs_super_block *disk_super = fs_info->super_copy; | |
2033 | struct list_head *head = &fs_info->space_info; | |
2034 | struct btrfs_space_info *found; | |
2035 | u64 total_used = 0; | |
2036 | u64 total_free_data = 0; | |
2037 | u64 total_free_meta = 0; | |
2038 | int bits = dentry->d_sb->s_blocksize_bits; | |
2039 | __be32 *fsid = (__be32 *)fs_info->fs_devices->fsid; | |
2040 | unsigned factor = 1; | |
2041 | struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv; | |
2042 | int ret; | |
2043 | u64 thresh = 0; | |
2044 | int mixed = 0; | |
2045 | ||
2046 | rcu_read_lock(); | |
2047 | list_for_each_entry_rcu(found, head, list) { | |
2048 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) { | |
2049 | int i; | |
2050 | ||
2051 | total_free_data += found->disk_total - found->disk_used; | |
2052 | total_free_data -= | |
2053 | btrfs_account_ro_block_groups_free_space(found); | |
2054 | ||
2055 | for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) { | |
2056 | if (!list_empty(&found->block_groups[i])) | |
2057 | factor = btrfs_bg_type_to_factor( | |
2058 | btrfs_raid_array[i].bg_flag); | |
2059 | } | |
2060 | } | |
2061 | ||
2062 | /* | |
2063 | * Metadata in mixed block goup profiles are accounted in data | |
2064 | */ | |
2065 | if (!mixed && found->flags & BTRFS_BLOCK_GROUP_METADATA) { | |
2066 | if (found->flags & BTRFS_BLOCK_GROUP_DATA) | |
2067 | mixed = 1; | |
2068 | else | |
2069 | total_free_meta += found->disk_total - | |
2070 | found->disk_used; | |
2071 | } | |
2072 | ||
2073 | total_used += found->disk_used; | |
2074 | } | |
2075 | ||
2076 | rcu_read_unlock(); | |
2077 | ||
2078 | buf->f_blocks = div_u64(btrfs_super_total_bytes(disk_super), factor); | |
2079 | buf->f_blocks >>= bits; | |
2080 | buf->f_bfree = buf->f_blocks - (div_u64(total_used, factor) >> bits); | |
2081 | ||
2082 | /* Account global block reserve as used, it's in logical size already */ | |
2083 | spin_lock(&block_rsv->lock); | |
2084 | /* Mixed block groups accounting is not byte-accurate, avoid overflow */ | |
2085 | if (buf->f_bfree >= block_rsv->size >> bits) | |
2086 | buf->f_bfree -= block_rsv->size >> bits; | |
2087 | else | |
2088 | buf->f_bfree = 0; | |
2089 | spin_unlock(&block_rsv->lock); | |
2090 | ||
2091 | buf->f_bavail = div_u64(total_free_data, factor); | |
2092 | ret = btrfs_calc_avail_data_space(fs_info, &total_free_data); | |
2093 | if (ret) | |
2094 | return ret; | |
2095 | buf->f_bavail += div_u64(total_free_data, factor); | |
2096 | buf->f_bavail = buf->f_bavail >> bits; | |
2097 | ||
2098 | /* | |
2099 | * We calculate the remaining metadata space minus global reserve. If | |
2100 | * this is (supposedly) smaller than zero, there's no space. But this | |
2101 | * does not hold in practice, the exhausted state happens where's still | |
2102 | * some positive delta. So we apply some guesswork and compare the | |
2103 | * delta to a 4M threshold. (Practically observed delta was ~2M.) | |
2104 | * | |
2105 | * We probably cannot calculate the exact threshold value because this | |
2106 | * depends on the internal reservations requested by various | |
2107 | * operations, so some operations that consume a few metadata will | |
2108 | * succeed even if the Avail is zero. But this is better than the other | |
2109 | * way around. | |
2110 | */ | |
2111 | thresh = SZ_4M; | |
2112 | ||
2113 | if (!mixed && total_free_meta - thresh < block_rsv->size) | |
2114 | buf->f_bavail = 0; | |
2115 | ||
2116 | buf->f_type = BTRFS_SUPER_MAGIC; | |
2117 | buf->f_bsize = dentry->d_sb->s_blocksize; | |
2118 | buf->f_namelen = BTRFS_NAME_LEN; | |
2119 | ||
2120 | /* We treat it as constant endianness (it doesn't matter _which_) | |
2121 | because we want the fsid to come out the same whether mounted | |
2122 | on a big-endian or little-endian host */ | |
2123 | buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]); | |
2124 | buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]); | |
2125 | /* Mask in the root object ID too, to disambiguate subvols */ | |
2126 | buf->f_fsid.val[0] ^= | |
2127 | BTRFS_I(d_inode(dentry))->root->root_key.objectid >> 32; | |
2128 | buf->f_fsid.val[1] ^= | |
2129 | BTRFS_I(d_inode(dentry))->root->root_key.objectid; | |
2130 | ||
2131 | return 0; | |
2132 | } | |
2133 | ||
2134 | static void btrfs_kill_super(struct super_block *sb) | |
2135 | { | |
2136 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
2137 | kill_anon_super(sb); | |
2138 | free_fs_info(fs_info); | |
2139 | } | |
2140 | ||
2141 | static struct file_system_type btrfs_fs_type = { | |
2142 | .owner = THIS_MODULE, | |
2143 | .name = "btrfs", | |
2144 | .mount = btrfs_mount, | |
2145 | .kill_sb = btrfs_kill_super, | |
2146 | .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA, | |
2147 | }; | |
2148 | ||
2149 | static struct file_system_type btrfs_root_fs_type = { | |
2150 | .owner = THIS_MODULE, | |
2151 | .name = "btrfs", | |
2152 | .mount = btrfs_mount_root, | |
2153 | .kill_sb = btrfs_kill_super, | |
2154 | .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA, | |
2155 | }; | |
2156 | ||
2157 | MODULE_ALIAS_FS("btrfs"); | |
2158 | ||
2159 | static int btrfs_control_open(struct inode *inode, struct file *file) | |
2160 | { | |
2161 | /* | |
2162 | * The control file's private_data is used to hold the | |
2163 | * transaction when it is started and is used to keep | |
2164 | * track of whether a transaction is already in progress. | |
2165 | */ | |
2166 | file->private_data = NULL; | |
2167 | return 0; | |
2168 | } | |
2169 | ||
2170 | /* | |
2171 | * used by btrfsctl to scan devices when no FS is mounted | |
2172 | */ | |
2173 | static long btrfs_control_ioctl(struct file *file, unsigned int cmd, | |
2174 | unsigned long arg) | |
2175 | { | |
2176 | struct btrfs_ioctl_vol_args *vol; | |
2177 | struct btrfs_device *device = NULL; | |
2178 | int ret = -ENOTTY; | |
2179 | ||
2180 | if (!capable(CAP_SYS_ADMIN)) | |
2181 | return -EPERM; | |
2182 | ||
2183 | vol = memdup_user((void __user *)arg, sizeof(*vol)); | |
2184 | if (IS_ERR(vol)) | |
2185 | return PTR_ERR(vol); | |
2186 | vol->name[BTRFS_PATH_NAME_MAX] = '\0'; | |
2187 | ||
2188 | switch (cmd) { | |
2189 | case BTRFS_IOC_SCAN_DEV: | |
2190 | mutex_lock(&uuid_mutex); | |
2191 | device = btrfs_scan_one_device(vol->name, FMODE_READ, | |
2192 | &btrfs_root_fs_type); | |
2193 | ret = PTR_ERR_OR_ZERO(device); | |
2194 | mutex_unlock(&uuid_mutex); | |
2195 | break; | |
2196 | case BTRFS_IOC_FORGET_DEV: | |
2197 | ret = btrfs_forget_devices(vol->name); | |
2198 | break; | |
2199 | case BTRFS_IOC_DEVICES_READY: | |
2200 | mutex_lock(&uuid_mutex); | |
2201 | device = btrfs_scan_one_device(vol->name, FMODE_READ, | |
2202 | &btrfs_root_fs_type); | |
2203 | if (IS_ERR(device)) { | |
2204 | mutex_unlock(&uuid_mutex); | |
2205 | ret = PTR_ERR(device); | |
2206 | break; | |
2207 | } | |
2208 | ret = !(device->fs_devices->num_devices == | |
2209 | device->fs_devices->total_devices); | |
2210 | mutex_unlock(&uuid_mutex); | |
2211 | break; | |
2212 | case BTRFS_IOC_GET_SUPPORTED_FEATURES: | |
2213 | ret = btrfs_ioctl_get_supported_features((void __user*)arg); | |
2214 | break; | |
2215 | } | |
2216 | ||
2217 | kfree(vol); | |
2218 | return ret; | |
2219 | } | |
2220 | ||
2221 | static int btrfs_freeze(struct super_block *sb) | |
2222 | { | |
2223 | struct btrfs_trans_handle *trans; | |
2224 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
2225 | struct btrfs_root *root = fs_info->tree_root; | |
2226 | ||
2227 | set_bit(BTRFS_FS_FROZEN, &fs_info->flags); | |
2228 | /* | |
2229 | * We don't need a barrier here, we'll wait for any transaction that | |
2230 | * could be in progress on other threads (and do delayed iputs that | |
2231 | * we want to avoid on a frozen filesystem), or do the commit | |
2232 | * ourselves. | |
2233 | */ | |
2234 | trans = btrfs_attach_transaction_barrier(root); | |
2235 | if (IS_ERR(trans)) { | |
2236 | /* no transaction, don't bother */ | |
2237 | if (PTR_ERR(trans) == -ENOENT) | |
2238 | return 0; | |
2239 | return PTR_ERR(trans); | |
2240 | } | |
2241 | return btrfs_commit_transaction(trans); | |
2242 | } | |
2243 | ||
2244 | static int btrfs_unfreeze(struct super_block *sb) | |
2245 | { | |
2246 | struct btrfs_fs_info *fs_info = btrfs_sb(sb); | |
2247 | ||
2248 | clear_bit(BTRFS_FS_FROZEN, &fs_info->flags); | |
2249 | return 0; | |
2250 | } | |
2251 | ||
2252 | static int btrfs_show_devname(struct seq_file *m, struct dentry *root) | |
2253 | { | |
2254 | struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb); | |
2255 | struct btrfs_fs_devices *cur_devices; | |
2256 | struct btrfs_device *dev, *first_dev = NULL; | |
2257 | struct list_head *head; | |
2258 | ||
2259 | /* | |
2260 | * Lightweight locking of the devices. We should not need | |
2261 | * device_list_mutex here as we only read the device data and the list | |
2262 | * is protected by RCU. Even if a device is deleted during the list | |
2263 | * traversals, we'll get valid data, the freeing callback will wait at | |
2264 | * least until the rcu_read_unlock. | |
2265 | */ | |
2266 | rcu_read_lock(); | |
2267 | cur_devices = fs_info->fs_devices; | |
2268 | while (cur_devices) { | |
2269 | head = &cur_devices->devices; | |
2270 | list_for_each_entry_rcu(dev, head, dev_list) { | |
2271 | if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) | |
2272 | continue; | |
2273 | if (!dev->name) | |
2274 | continue; | |
2275 | if (!first_dev || dev->devid < first_dev->devid) | |
2276 | first_dev = dev; | |
2277 | } | |
2278 | cur_devices = cur_devices->seed; | |
2279 | } | |
2280 | ||
2281 | if (first_dev) | |
2282 | seq_escape(m, rcu_str_deref(first_dev->name), " \t\n\\"); | |
2283 | else | |
2284 | WARN_ON(1); | |
2285 | rcu_read_unlock(); | |
2286 | return 0; | |
2287 | } | |
2288 | ||
2289 | static const struct super_operations btrfs_super_ops = { | |
2290 | .drop_inode = btrfs_drop_inode, | |
2291 | .evict_inode = btrfs_evict_inode, | |
2292 | .put_super = btrfs_put_super, | |
2293 | .sync_fs = btrfs_sync_fs, | |
2294 | .show_options = btrfs_show_options, | |
2295 | .show_devname = btrfs_show_devname, | |
2296 | .alloc_inode = btrfs_alloc_inode, | |
2297 | .destroy_inode = btrfs_destroy_inode, | |
2298 | .free_inode = btrfs_free_inode, | |
2299 | .statfs = btrfs_statfs, | |
2300 | .remount_fs = btrfs_remount, | |
2301 | .freeze_fs = btrfs_freeze, | |
2302 | .unfreeze_fs = btrfs_unfreeze, | |
2303 | }; | |
2304 | ||
2305 | static const struct file_operations btrfs_ctl_fops = { | |
2306 | .open = btrfs_control_open, | |
2307 | .unlocked_ioctl = btrfs_control_ioctl, | |
2308 | .compat_ioctl = btrfs_control_ioctl, | |
2309 | .owner = THIS_MODULE, | |
2310 | .llseek = noop_llseek, | |
2311 | }; | |
2312 | ||
2313 | static struct miscdevice btrfs_misc = { | |
2314 | .minor = BTRFS_MINOR, | |
2315 | .name = "btrfs-control", | |
2316 | .fops = &btrfs_ctl_fops | |
2317 | }; | |
2318 | ||
2319 | MODULE_ALIAS_MISCDEV(BTRFS_MINOR); | |
2320 | MODULE_ALIAS("devname:btrfs-control"); | |
2321 | ||
2322 | static int __init btrfs_interface_init(void) | |
2323 | { | |
2324 | return misc_register(&btrfs_misc); | |
2325 | } | |
2326 | ||
2327 | static __cold void btrfs_interface_exit(void) | |
2328 | { | |
2329 | misc_deregister(&btrfs_misc); | |
2330 | } | |
2331 | ||
2332 | static void __init btrfs_print_mod_info(void) | |
2333 | { | |
2334 | static const char options[] = "" | |
2335 | #ifdef CONFIG_BTRFS_DEBUG | |
2336 | ", debug=on" | |
2337 | #endif | |
2338 | #ifdef CONFIG_BTRFS_ASSERT | |
2339 | ", assert=on" | |
2340 | #endif | |
2341 | #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY | |
2342 | ", integrity-checker=on" | |
2343 | #endif | |
2344 | #ifdef CONFIG_BTRFS_FS_REF_VERIFY | |
2345 | ", ref-verify=on" | |
2346 | #endif | |
2347 | ; | |
2348 | pr_info("Btrfs loaded, crc32c=%s%s\n", crc32c_impl(), options); | |
2349 | } | |
2350 | ||
2351 | static int __init init_btrfs_fs(void) | |
2352 | { | |
2353 | int err; | |
2354 | ||
2355 | btrfs_props_init(); | |
2356 | ||
2357 | err = btrfs_init_sysfs(); | |
2358 | if (err) | |
2359 | return err; | |
2360 | ||
2361 | btrfs_init_compress(); | |
2362 | ||
2363 | err = btrfs_init_cachep(); | |
2364 | if (err) | |
2365 | goto free_compress; | |
2366 | ||
2367 | err = extent_io_init(); | |
2368 | if (err) | |
2369 | goto free_cachep; | |
2370 | ||
2371 | err = extent_map_init(); | |
2372 | if (err) | |
2373 | goto free_extent_io; | |
2374 | ||
2375 | err = ordered_data_init(); | |
2376 | if (err) | |
2377 | goto free_extent_map; | |
2378 | ||
2379 | err = btrfs_delayed_inode_init(); | |
2380 | if (err) | |
2381 | goto free_ordered_data; | |
2382 | ||
2383 | err = btrfs_auto_defrag_init(); | |
2384 | if (err) | |
2385 | goto free_delayed_inode; | |
2386 | ||
2387 | err = btrfs_delayed_ref_init(); | |
2388 | if (err) | |
2389 | goto free_auto_defrag; | |
2390 | ||
2391 | err = btrfs_prelim_ref_init(); | |
2392 | if (err) | |
2393 | goto free_delayed_ref; | |
2394 | ||
2395 | err = btrfs_end_io_wq_init(); | |
2396 | if (err) | |
2397 | goto free_prelim_ref; | |
2398 | ||
2399 | err = btrfs_interface_init(); | |
2400 | if (err) | |
2401 | goto free_end_io_wq; | |
2402 | ||
2403 | btrfs_init_lockdep(); | |
2404 | ||
2405 | btrfs_print_mod_info(); | |
2406 | ||
2407 | err = btrfs_run_sanity_tests(); | |
2408 | if (err) | |
2409 | goto unregister_ioctl; | |
2410 | ||
2411 | err = register_filesystem(&btrfs_fs_type); | |
2412 | if (err) | |
2413 | goto unregister_ioctl; | |
2414 | ||
2415 | return 0; | |
2416 | ||
2417 | unregister_ioctl: | |
2418 | btrfs_interface_exit(); | |
2419 | free_end_io_wq: | |
2420 | btrfs_end_io_wq_exit(); | |
2421 | free_prelim_ref: | |
2422 | btrfs_prelim_ref_exit(); | |
2423 | free_delayed_ref: | |
2424 | btrfs_delayed_ref_exit(); | |
2425 | free_auto_defrag: | |
2426 | btrfs_auto_defrag_exit(); | |
2427 | free_delayed_inode: | |
2428 | btrfs_delayed_inode_exit(); | |
2429 | free_ordered_data: | |
2430 | ordered_data_exit(); | |
2431 | free_extent_map: | |
2432 | extent_map_exit(); | |
2433 | free_extent_io: | |
2434 | extent_io_exit(); | |
2435 | free_cachep: | |
2436 | btrfs_destroy_cachep(); | |
2437 | free_compress: | |
2438 | btrfs_exit_compress(); | |
2439 | btrfs_exit_sysfs(); | |
2440 | ||
2441 | return err; | |
2442 | } | |
2443 | ||
2444 | static void __exit exit_btrfs_fs(void) | |
2445 | { | |
2446 | btrfs_destroy_cachep(); | |
2447 | btrfs_delayed_ref_exit(); | |
2448 | btrfs_auto_defrag_exit(); | |
2449 | btrfs_delayed_inode_exit(); | |
2450 | btrfs_prelim_ref_exit(); | |
2451 | ordered_data_exit(); | |
2452 | extent_map_exit(); | |
2453 | extent_io_exit(); | |
2454 | btrfs_interface_exit(); | |
2455 | btrfs_end_io_wq_exit(); | |
2456 | unregister_filesystem(&btrfs_fs_type); | |
2457 | btrfs_exit_sysfs(); | |
2458 | btrfs_cleanup_fs_uuids(); | |
2459 | btrfs_exit_compress(); | |
2460 | } | |
2461 | ||
2462 | late_initcall(init_btrfs_fs); | |
2463 | module_exit(exit_btrfs_fs) | |
2464 | ||
2465 | MODULE_LICENSE("GPL"); | |
2466 | MODULE_SOFTDEP("pre: crc32c"); |