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 "sysfs.h"
47 #include "tests/btrfs-tests.h"
48 #include "block-group.h"
49 #include "discard.h"
50
51 #include "qgroup.h"
52 #define CREATE_TRACE_POINTS
53 #include <trace/events/btrfs.h>
54
55 static const struct super_operations btrfs_super_ops;
56
57 /*
58 * Types for mounting the default subvolume and a subvolume explicitly
59 * requested by subvol=/path. That way the callchain is straightforward and we
60 * don't have to play tricks with the mount options and recursive calls to
61 * btrfs_mount.
62 *
63 * The new btrfs_root_fs_type also servers as a tag for the bdev_holder.
64 */
65 static struct file_system_type btrfs_fs_type;
66 static struct file_system_type btrfs_root_fs_type;
67
68 static int btrfs_remount(struct super_block *sb, int *flags, char *data);
69
70 /*
71 * Generally the error codes correspond to their respective errors, but there
72 * are a few special cases.
73 *
74 * EUCLEAN: Any sort of corruption that we encounter. The tree-checker for
75 * instance will return EUCLEAN if any of the blocks are corrupted in
76 * a way that is problematic. We want to reserve EUCLEAN for these
77 * sort of corruptions.
78 *
79 * EROFS: If we check BTRFS_FS_STATE_ERROR and fail out with a return error, we
80 * need to use EROFS for this case. We will have no idea of the
81 * original failure, that will have been reported at the time we tripped
82 * over the error. Each subsequent error that doesn't have any context
83 * of the original error should use EROFS when handling BTRFS_FS_STATE_ERROR.
84 */
btrfs_decode_error(int errno)85 const char * __attribute_const__ btrfs_decode_error(int errno)
86 {
87 char *errstr = "unknown";
88
89 switch (errno) {
90 case -ENOENT: /* -2 */
91 errstr = "No such entry";
92 break;
93 case -EIO: /* -5 */
94 errstr = "IO failure";
95 break;
96 case -ENOMEM: /* -12*/
97 errstr = "Out of memory";
98 break;
99 case -EEXIST: /* -17 */
100 errstr = "Object already exists";
101 break;
102 case -ENOSPC: /* -28 */
103 errstr = "No space left";
104 break;
105 case -EROFS: /* -30 */
106 errstr = "Readonly filesystem";
107 break;
108 case -EOPNOTSUPP: /* -95 */
109 errstr = "Operation not supported";
110 break;
111 case -EUCLEAN: /* -117 */
112 errstr = "Filesystem corrupted";
113 break;
114 case -EDQUOT: /* -122 */
115 errstr = "Quota exceeded";
116 break;
117 }
118
119 return errstr;
120 }
121
122 /*
123 * __btrfs_handle_fs_error decodes expected errors from the caller and
124 * invokes the appropriate error response.
125 */
126 __cold
__btrfs_handle_fs_error(struct btrfs_fs_info * fs_info,const char * function,unsigned int line,int errno,const char * fmt,...)127 void __btrfs_handle_fs_error(struct btrfs_fs_info *fs_info, const char *function,
128 unsigned int line, int errno, const char *fmt, ...)
129 {
130 struct super_block *sb = fs_info->sb;
131 #ifdef CONFIG_PRINTK
132 const char *errstr;
133 #endif
134
135 /*
136 * Special case: if the error is EROFS, and we're already
137 * under SB_RDONLY, then it is safe here.
138 */
139 if (errno == -EROFS && sb_rdonly(sb))
140 return;
141
142 #ifdef CONFIG_PRINTK
143 errstr = btrfs_decode_error(errno);
144 if (fmt) {
145 struct va_format vaf;
146 va_list args;
147
148 va_start(args, fmt);
149 vaf.fmt = fmt;
150 vaf.va = &args;
151
152 pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s (%pV)\n",
153 sb->s_id, function, line, errno, errstr, &vaf);
154 va_end(args);
155 } else {
156 pr_crit("BTRFS: error (device %s) in %s:%d: errno=%d %s\n",
157 sb->s_id, function, line, errno, errstr);
158 }
159 #endif
160
161 /*
162 * Today we only save the error info to memory. Long term we'll
163 * also send it down to the disk
164 */
165 set_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state);
166
167 /* Don't go through full error handling during mount */
168 if (!(sb->s_flags & SB_BORN))
169 return;
170
171 if (sb_rdonly(sb))
172 return;
173
174 btrfs_discard_stop(fs_info);
175
176 /* btrfs handle error by forcing the filesystem readonly */
177 sb->s_flags |= SB_RDONLY;
178 btrfs_info(fs_info, "forced readonly");
179 /*
180 * Note that a running device replace operation is not canceled here
181 * although there is no way to update the progress. It would add the
182 * risk of a deadlock, therefore the canceling is omitted. The only
183 * penalty is that some I/O remains active until the procedure
184 * completes. The next time when the filesystem is mounted writable
185 * again, the device replace operation continues.
186 */
187 }
188
189 #ifdef CONFIG_PRINTK
190 static const char * const logtypes[] = {
191 "emergency",
192 "alert",
193 "critical",
194 "error",
195 "warning",
196 "notice",
197 "info",
198 "debug",
199 };
200
201
202 /*
203 * Use one ratelimit state per log level so that a flood of less important
204 * messages doesn't cause more important ones to be dropped.
205 */
206 static struct ratelimit_state printk_limits[] = {
207 RATELIMIT_STATE_INIT(printk_limits[0], DEFAULT_RATELIMIT_INTERVAL, 100),
208 RATELIMIT_STATE_INIT(printk_limits[1], DEFAULT_RATELIMIT_INTERVAL, 100),
209 RATELIMIT_STATE_INIT(printk_limits[2], DEFAULT_RATELIMIT_INTERVAL, 100),
210 RATELIMIT_STATE_INIT(printk_limits[3], DEFAULT_RATELIMIT_INTERVAL, 100),
211 RATELIMIT_STATE_INIT(printk_limits[4], DEFAULT_RATELIMIT_INTERVAL, 100),
212 RATELIMIT_STATE_INIT(printk_limits[5], DEFAULT_RATELIMIT_INTERVAL, 100),
213 RATELIMIT_STATE_INIT(printk_limits[6], DEFAULT_RATELIMIT_INTERVAL, 100),
214 RATELIMIT_STATE_INIT(printk_limits[7], DEFAULT_RATELIMIT_INTERVAL, 100),
215 };
216
btrfs_printk(const struct btrfs_fs_info * fs_info,const char * fmt,...)217 void __cold btrfs_printk(const struct btrfs_fs_info *fs_info, const char *fmt, ...)
218 {
219 char lvl[PRINTK_MAX_SINGLE_HEADER_LEN + 1] = "\0";
220 struct va_format vaf;
221 va_list args;
222 int kern_level;
223 const char *type = logtypes[4];
224 struct ratelimit_state *ratelimit = &printk_limits[4];
225
226 va_start(args, fmt);
227
228 while ((kern_level = printk_get_level(fmt)) != 0) {
229 size_t size = printk_skip_level(fmt) - fmt;
230
231 if (kern_level >= '0' && kern_level <= '7') {
232 memcpy(lvl, fmt, size);
233 lvl[size] = '\0';
234 type = logtypes[kern_level - '0'];
235 ratelimit = &printk_limits[kern_level - '0'];
236 }
237 fmt += size;
238 }
239
240 vaf.fmt = fmt;
241 vaf.va = &args;
242
243 if (__ratelimit(ratelimit))
244 printk("%sBTRFS %s (device %s): %pV\n", lvl, type,
245 fs_info ? fs_info->sb->s_id : "<unknown>", &vaf);
246
247 va_end(args);
248 }
249 #endif
250
251 /*
252 * We only mark the transaction aborted and then set the file system read-only.
253 * This will prevent new transactions from starting or trying to join this
254 * one.
255 *
256 * This means that error recovery at the call site is limited to freeing
257 * any local memory allocations and passing the error code up without
258 * further cleanup. The transaction should complete as it normally would
259 * in the call path but will return -EIO.
260 *
261 * We'll complete the cleanup in btrfs_end_transaction and
262 * btrfs_commit_transaction.
263 */
264 __cold
__btrfs_abort_transaction(struct btrfs_trans_handle * trans,const char * function,unsigned int line,int errno)265 void __btrfs_abort_transaction(struct btrfs_trans_handle *trans,
266 const char *function,
267 unsigned int line, int errno)
268 {
269 struct btrfs_fs_info *fs_info = trans->fs_info;
270
271 WRITE_ONCE(trans->aborted, errno);
272 /* Nothing used. The other threads that have joined this
273 * transaction may be able to continue. */
274 if (!trans->dirty && list_empty(&trans->new_bgs)) {
275 const char *errstr;
276
277 errstr = btrfs_decode_error(errno);
278 btrfs_warn(fs_info,
279 "%s:%d: Aborting unused transaction(%s).",
280 function, line, errstr);
281 return;
282 }
283 WRITE_ONCE(trans->transaction->aborted, errno);
284 /* Wake up anybody who may be waiting on this transaction */
285 wake_up(&fs_info->transaction_wait);
286 wake_up(&fs_info->transaction_blocked_wait);
287 __btrfs_handle_fs_error(fs_info, function, line, errno, NULL);
288 }
289 /*
290 * __btrfs_panic decodes unexpected, fatal errors from the caller,
291 * issues an alert, and either panics or BUGs, depending on mount options.
292 */
293 __cold
__btrfs_panic(struct btrfs_fs_info * fs_info,const char * function,unsigned int line,int errno,const char * fmt,...)294 void __btrfs_panic(struct btrfs_fs_info *fs_info, const char *function,
295 unsigned int line, int errno, const char *fmt, ...)
296 {
297 char *s_id = "<unknown>";
298 const char *errstr;
299 struct va_format vaf = { .fmt = fmt };
300 va_list args;
301
302 if (fs_info)
303 s_id = fs_info->sb->s_id;
304
305 va_start(args, fmt);
306 vaf.va = &args;
307
308 errstr = btrfs_decode_error(errno);
309 if (fs_info && (btrfs_test_opt(fs_info, PANIC_ON_FATAL_ERROR)))
310 panic(KERN_CRIT "BTRFS panic (device %s) in %s:%d: %pV (errno=%d %s)\n",
311 s_id, function, line, &vaf, errno, errstr);
312
313 btrfs_crit(fs_info, "panic in %s:%d: %pV (errno=%d %s)",
314 function, line, &vaf, errno, errstr);
315 va_end(args);
316 /* Caller calls BUG() */
317 }
318
btrfs_put_super(struct super_block * sb)319 static void btrfs_put_super(struct super_block *sb)
320 {
321 close_ctree(btrfs_sb(sb));
322 }
323
324 enum {
325 Opt_acl, Opt_noacl,
326 Opt_clear_cache,
327 Opt_commit_interval,
328 Opt_compress,
329 Opt_compress_force,
330 Opt_compress_force_type,
331 Opt_compress_type,
332 Opt_degraded,
333 Opt_device,
334 Opt_fatal_errors,
335 Opt_flushoncommit, Opt_noflushoncommit,
336 Opt_inode_cache, Opt_noinode_cache,
337 Opt_max_inline,
338 Opt_barrier, Opt_nobarrier,
339 Opt_datacow, Opt_nodatacow,
340 Opt_datasum, Opt_nodatasum,
341 Opt_defrag, Opt_nodefrag,
342 Opt_discard, Opt_nodiscard,
343 Opt_discard_mode,
344 Opt_norecovery,
345 Opt_ratio,
346 Opt_rescan_uuid_tree,
347 Opt_skip_balance,
348 Opt_space_cache, Opt_no_space_cache,
349 Opt_space_cache_version,
350 Opt_ssd, Opt_nossd,
351 Opt_ssd_spread, Opt_nossd_spread,
352 Opt_subvol,
353 Opt_subvol_empty,
354 Opt_subvolid,
355 Opt_thread_pool,
356 Opt_treelog, Opt_notreelog,
357 Opt_user_subvol_rm_allowed,
358
359 /* Rescue options */
360 Opt_rescue,
361 Opt_usebackuproot,
362 Opt_nologreplay,
363
364 /* Deprecated options */
365 Opt_recovery,
366
367 /* Debugging options */
368 Opt_check_integrity,
369 Opt_check_integrity_including_extent_data,
370 Opt_check_integrity_print_mask,
371 Opt_enospc_debug, Opt_noenospc_debug,
372 #ifdef CONFIG_BTRFS_DEBUG
373 Opt_fragment_data, Opt_fragment_metadata, Opt_fragment_all,
374 #endif
375 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
376 Opt_ref_verify,
377 #endif
378 Opt_err,
379 };
380
381 static const match_table_t tokens = {
382 {Opt_acl, "acl"},
383 {Opt_noacl, "noacl"},
384 {Opt_clear_cache, "clear_cache"},
385 {Opt_commit_interval, "commit=%u"},
386 {Opt_compress, "compress"},
387 {Opt_compress_type, "compress=%s"},
388 {Opt_compress_force, "compress-force"},
389 {Opt_compress_force_type, "compress-force=%s"},
390 {Opt_degraded, "degraded"},
391 {Opt_device, "device=%s"},
392 {Opt_fatal_errors, "fatal_errors=%s"},
393 {Opt_flushoncommit, "flushoncommit"},
394 {Opt_noflushoncommit, "noflushoncommit"},
395 {Opt_inode_cache, "inode_cache"},
396 {Opt_noinode_cache, "noinode_cache"},
397 {Opt_max_inline, "max_inline=%s"},
398 {Opt_barrier, "barrier"},
399 {Opt_nobarrier, "nobarrier"},
400 {Opt_datacow, "datacow"},
401 {Opt_nodatacow, "nodatacow"},
402 {Opt_datasum, "datasum"},
403 {Opt_nodatasum, "nodatasum"},
404 {Opt_defrag, "autodefrag"},
405 {Opt_nodefrag, "noautodefrag"},
406 {Opt_discard, "discard"},
407 {Opt_discard_mode, "discard=%s"},
408 {Opt_nodiscard, "nodiscard"},
409 {Opt_norecovery, "norecovery"},
410 {Opt_ratio, "metadata_ratio=%u"},
411 {Opt_rescan_uuid_tree, "rescan_uuid_tree"},
412 {Opt_skip_balance, "skip_balance"},
413 {Opt_space_cache, "space_cache"},
414 {Opt_no_space_cache, "nospace_cache"},
415 {Opt_space_cache_version, "space_cache=%s"},
416 {Opt_ssd, "ssd"},
417 {Opt_nossd, "nossd"},
418 {Opt_ssd_spread, "ssd_spread"},
419 {Opt_nossd_spread, "nossd_spread"},
420 {Opt_subvol, "subvol=%s"},
421 {Opt_subvol_empty, "subvol="},
422 {Opt_subvolid, "subvolid=%s"},
423 {Opt_thread_pool, "thread_pool=%u"},
424 {Opt_treelog, "treelog"},
425 {Opt_notreelog, "notreelog"},
426 {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"},
427
428 /* Rescue options */
429 {Opt_rescue, "rescue=%s"},
430 /* Deprecated, with alias rescue=nologreplay */
431 {Opt_nologreplay, "nologreplay"},
432 /* Deprecated, with alias rescue=usebackuproot */
433 {Opt_usebackuproot, "usebackuproot"},
434
435 /* Deprecated options */
436 {Opt_recovery, "recovery"},
437
438 /* Debugging options */
439 {Opt_check_integrity, "check_int"},
440 {Opt_check_integrity_including_extent_data, "check_int_data"},
441 {Opt_check_integrity_print_mask, "check_int_print_mask=%u"},
442 {Opt_enospc_debug, "enospc_debug"},
443 {Opt_noenospc_debug, "noenospc_debug"},
444 #ifdef CONFIG_BTRFS_DEBUG
445 {Opt_fragment_data, "fragment=data"},
446 {Opt_fragment_metadata, "fragment=metadata"},
447 {Opt_fragment_all, "fragment=all"},
448 #endif
449 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
450 {Opt_ref_verify, "ref_verify"},
451 #endif
452 {Opt_err, NULL},
453 };
454
455 static const match_table_t rescue_tokens = {
456 {Opt_usebackuproot, "usebackuproot"},
457 {Opt_nologreplay, "nologreplay"},
458 {Opt_err, NULL},
459 };
460
parse_rescue_options(struct btrfs_fs_info * info,const char * options)461 static int parse_rescue_options(struct btrfs_fs_info *info, const char *options)
462 {
463 char *opts;
464 char *orig;
465 char *p;
466 substring_t args[MAX_OPT_ARGS];
467 int ret = 0;
468
469 opts = kstrdup(options, GFP_KERNEL);
470 if (!opts)
471 return -ENOMEM;
472 orig = opts;
473
474 while ((p = strsep(&opts, ":")) != NULL) {
475 int token;
476
477 if (!*p)
478 continue;
479 token = match_token(p, rescue_tokens, args);
480 switch (token){
481 case Opt_usebackuproot:
482 btrfs_info(info,
483 "trying to use backup root at mount time");
484 btrfs_set_opt(info->mount_opt, USEBACKUPROOT);
485 break;
486 case Opt_nologreplay:
487 btrfs_set_and_info(info, NOLOGREPLAY,
488 "disabling log replay at mount time");
489 break;
490 case Opt_err:
491 btrfs_info(info, "unrecognized rescue option '%s'", p);
492 ret = -EINVAL;
493 goto out;
494 default:
495 break;
496 }
497
498 }
499 out:
500 kfree(orig);
501 return ret;
502 }
503
504 /*
505 * Regular mount options parser. Everything that is needed only when
506 * reading in a new superblock is parsed here.
507 * XXX JDM: This needs to be cleaned up for remount.
508 */
btrfs_parse_options(struct btrfs_fs_info * info,char * options,unsigned long new_flags)509 int btrfs_parse_options(struct btrfs_fs_info *info, char *options,
510 unsigned long new_flags)
511 {
512 substring_t args[MAX_OPT_ARGS];
513 char *p, *num;
514 u64 cache_gen;
515 int intarg;
516 int ret = 0;
517 char *compress_type;
518 bool compress_force = false;
519 enum btrfs_compression_type saved_compress_type;
520 int saved_compress_level;
521 bool saved_compress_force;
522 int no_compress = 0;
523
524 cache_gen = btrfs_super_cache_generation(info->super_copy);
525 if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE))
526 btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE);
527 else if (cache_gen)
528 btrfs_set_opt(info->mount_opt, SPACE_CACHE);
529
530 /*
531 * Even the options are empty, we still need to do extra check
532 * against new flags
533 */
534 if (!options)
535 goto check;
536
537 while ((p = strsep(&options, ",")) != NULL) {
538 int token;
539 if (!*p)
540 continue;
541
542 token = match_token(p, tokens, args);
543 switch (token) {
544 case Opt_degraded:
545 btrfs_info(info, "allowing degraded mounts");
546 btrfs_set_opt(info->mount_opt, DEGRADED);
547 break;
548 case Opt_subvol:
549 case Opt_subvol_empty:
550 case Opt_subvolid:
551 case Opt_device:
552 /*
553 * These are parsed by btrfs_parse_subvol_options or
554 * btrfs_parse_device_options and can be ignored here.
555 */
556 break;
557 case Opt_nodatasum:
558 btrfs_set_and_info(info, NODATASUM,
559 "setting nodatasum");
560 break;
561 case Opt_datasum:
562 if (btrfs_test_opt(info, NODATASUM)) {
563 if (btrfs_test_opt(info, NODATACOW))
564 btrfs_info(info,
565 "setting datasum, datacow enabled");
566 else
567 btrfs_info(info, "setting datasum");
568 }
569 btrfs_clear_opt(info->mount_opt, NODATACOW);
570 btrfs_clear_opt(info->mount_opt, NODATASUM);
571 break;
572 case Opt_nodatacow:
573 if (!btrfs_test_opt(info, NODATACOW)) {
574 if (!btrfs_test_opt(info, COMPRESS) ||
575 !btrfs_test_opt(info, FORCE_COMPRESS)) {
576 btrfs_info(info,
577 "setting nodatacow, compression disabled");
578 } else {
579 btrfs_info(info, "setting nodatacow");
580 }
581 }
582 btrfs_clear_opt(info->mount_opt, COMPRESS);
583 btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
584 btrfs_set_opt(info->mount_opt, NODATACOW);
585 btrfs_set_opt(info->mount_opt, NODATASUM);
586 break;
587 case Opt_datacow:
588 btrfs_clear_and_info(info, NODATACOW,
589 "setting datacow");
590 break;
591 case Opt_compress_force:
592 case Opt_compress_force_type:
593 compress_force = true;
594 fallthrough;
595 case Opt_compress:
596 case Opt_compress_type:
597 saved_compress_type = btrfs_test_opt(info,
598 COMPRESS) ?
599 info->compress_type : BTRFS_COMPRESS_NONE;
600 saved_compress_force =
601 btrfs_test_opt(info, FORCE_COMPRESS);
602 saved_compress_level = info->compress_level;
603 if (token == Opt_compress ||
604 token == Opt_compress_force ||
605 strncmp(args[0].from, "zlib", 4) == 0) {
606 compress_type = "zlib";
607
608 info->compress_type = BTRFS_COMPRESS_ZLIB;
609 info->compress_level = BTRFS_ZLIB_DEFAULT_LEVEL;
610 /*
611 * args[0] contains uninitialized data since
612 * for these tokens we don't expect any
613 * parameter.
614 */
615 if (token != Opt_compress &&
616 token != Opt_compress_force)
617 info->compress_level =
618 btrfs_compress_str2level(
619 BTRFS_COMPRESS_ZLIB,
620 args[0].from + 4);
621 btrfs_set_opt(info->mount_opt, COMPRESS);
622 btrfs_clear_opt(info->mount_opt, NODATACOW);
623 btrfs_clear_opt(info->mount_opt, NODATASUM);
624 no_compress = 0;
625 } else if (strncmp(args[0].from, "lzo", 3) == 0) {
626 compress_type = "lzo";
627 info->compress_type = BTRFS_COMPRESS_LZO;
628 info->compress_level = 0;
629 btrfs_set_opt(info->mount_opt, COMPRESS);
630 btrfs_clear_opt(info->mount_opt, NODATACOW);
631 btrfs_clear_opt(info->mount_opt, NODATASUM);
632 btrfs_set_fs_incompat(info, COMPRESS_LZO);
633 no_compress = 0;
634 } else if (strncmp(args[0].from, "zstd", 4) == 0) {
635 compress_type = "zstd";
636 info->compress_type = BTRFS_COMPRESS_ZSTD;
637 info->compress_level =
638 btrfs_compress_str2level(
639 BTRFS_COMPRESS_ZSTD,
640 args[0].from + 4);
641 btrfs_set_opt(info->mount_opt, COMPRESS);
642 btrfs_clear_opt(info->mount_opt, NODATACOW);
643 btrfs_clear_opt(info->mount_opt, NODATASUM);
644 btrfs_set_fs_incompat(info, COMPRESS_ZSTD);
645 no_compress = 0;
646 } else if (strncmp(args[0].from, "no", 2) == 0) {
647 compress_type = "no";
648 info->compress_level = 0;
649 info->compress_type = 0;
650 btrfs_clear_opt(info->mount_opt, COMPRESS);
651 btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
652 compress_force = false;
653 no_compress++;
654 } else {
655 btrfs_err(info, "unrecognized compression value %s",
656 args[0].from);
657 ret = -EINVAL;
658 goto out;
659 }
660
661 if (compress_force) {
662 btrfs_set_opt(info->mount_opt, FORCE_COMPRESS);
663 } else {
664 /*
665 * If we remount from compress-force=xxx to
666 * compress=xxx, we need clear FORCE_COMPRESS
667 * flag, otherwise, there is no way for users
668 * to disable forcible compression separately.
669 */
670 btrfs_clear_opt(info->mount_opt, FORCE_COMPRESS);
671 }
672 if (no_compress == 1) {
673 btrfs_info(info, "use no compression");
674 } else if ((info->compress_type != saved_compress_type) ||
675 (compress_force != saved_compress_force) ||
676 (info->compress_level != saved_compress_level)) {
677 btrfs_info(info, "%s %s compression, level %d",
678 (compress_force) ? "force" : "use",
679 compress_type, info->compress_level);
680 }
681 compress_force = false;
682 break;
683 case Opt_ssd:
684 btrfs_set_and_info(info, SSD,
685 "enabling ssd optimizations");
686 btrfs_clear_opt(info->mount_opt, NOSSD);
687 break;
688 case Opt_ssd_spread:
689 btrfs_set_and_info(info, SSD,
690 "enabling ssd optimizations");
691 btrfs_set_and_info(info, SSD_SPREAD,
692 "using spread ssd allocation scheme");
693 btrfs_clear_opt(info->mount_opt, NOSSD);
694 break;
695 case Opt_nossd:
696 btrfs_set_opt(info->mount_opt, NOSSD);
697 btrfs_clear_and_info(info, SSD,
698 "not using ssd optimizations");
699 fallthrough;
700 case Opt_nossd_spread:
701 btrfs_clear_and_info(info, SSD_SPREAD,
702 "not using spread ssd allocation scheme");
703 break;
704 case Opt_barrier:
705 btrfs_clear_and_info(info, NOBARRIER,
706 "turning on barriers");
707 break;
708 case Opt_nobarrier:
709 btrfs_set_and_info(info, NOBARRIER,
710 "turning off barriers");
711 break;
712 case Opt_thread_pool:
713 ret = match_int(&args[0], &intarg);
714 if (ret) {
715 btrfs_err(info, "unrecognized thread_pool value %s",
716 args[0].from);
717 goto out;
718 } else if (intarg == 0) {
719 btrfs_err(info, "invalid value 0 for thread_pool");
720 ret = -EINVAL;
721 goto out;
722 }
723 info->thread_pool_size = intarg;
724 break;
725 case Opt_max_inline:
726 num = match_strdup(&args[0]);
727 if (num) {
728 info->max_inline = memparse(num, NULL);
729 kfree(num);
730
731 if (info->max_inline) {
732 info->max_inline = min_t(u64,
733 info->max_inline,
734 info->sectorsize);
735 }
736 btrfs_info(info, "max_inline at %llu",
737 info->max_inline);
738 } else {
739 ret = -ENOMEM;
740 goto out;
741 }
742 break;
743 case Opt_acl:
744 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
745 info->sb->s_flags |= SB_POSIXACL;
746 break;
747 #else
748 btrfs_err(info, "support for ACL not compiled in!");
749 ret = -EINVAL;
750 goto out;
751 #endif
752 case Opt_noacl:
753 info->sb->s_flags &= ~SB_POSIXACL;
754 break;
755 case Opt_notreelog:
756 btrfs_set_and_info(info, NOTREELOG,
757 "disabling tree log");
758 break;
759 case Opt_treelog:
760 btrfs_clear_and_info(info, NOTREELOG,
761 "enabling tree log");
762 break;
763 case Opt_norecovery:
764 case Opt_nologreplay:
765 btrfs_warn(info,
766 "'nologreplay' is deprecated, use 'rescue=nologreplay' instead");
767 btrfs_set_and_info(info, NOLOGREPLAY,
768 "disabling log replay at mount time");
769 break;
770 case Opt_flushoncommit:
771 btrfs_set_and_info(info, FLUSHONCOMMIT,
772 "turning on flush-on-commit");
773 break;
774 case Opt_noflushoncommit:
775 btrfs_clear_and_info(info, FLUSHONCOMMIT,
776 "turning off flush-on-commit");
777 break;
778 case Opt_ratio:
779 ret = match_int(&args[0], &intarg);
780 if (ret) {
781 btrfs_err(info, "unrecognized metadata_ratio value %s",
782 args[0].from);
783 goto out;
784 }
785 info->metadata_ratio = intarg;
786 btrfs_info(info, "metadata ratio %u",
787 info->metadata_ratio);
788 break;
789 case Opt_discard:
790 case Opt_discard_mode:
791 if (token == Opt_discard ||
792 strcmp(args[0].from, "sync") == 0) {
793 btrfs_clear_opt(info->mount_opt, DISCARD_ASYNC);
794 btrfs_set_and_info(info, DISCARD_SYNC,
795 "turning on sync discard");
796 } else if (strcmp(args[0].from, "async") == 0) {
797 btrfs_clear_opt(info->mount_opt, DISCARD_SYNC);
798 btrfs_set_and_info(info, DISCARD_ASYNC,
799 "turning on async discard");
800 } else {
801 btrfs_err(info, "unrecognized discard mode value %s",
802 args[0].from);
803 ret = -EINVAL;
804 goto out;
805 }
806 break;
807 case Opt_nodiscard:
808 btrfs_clear_and_info(info, DISCARD_SYNC,
809 "turning off discard");
810 btrfs_clear_and_info(info, DISCARD_ASYNC,
811 "turning off async discard");
812 break;
813 case Opt_space_cache:
814 case Opt_space_cache_version:
815 if (token == Opt_space_cache ||
816 strcmp(args[0].from, "v1") == 0) {
817 btrfs_clear_opt(info->mount_opt,
818 FREE_SPACE_TREE);
819 btrfs_set_and_info(info, SPACE_CACHE,
820 "enabling disk space caching");
821 } else if (strcmp(args[0].from, "v2") == 0) {
822 btrfs_clear_opt(info->mount_opt,
823 SPACE_CACHE);
824 btrfs_set_and_info(info, FREE_SPACE_TREE,
825 "enabling free space tree");
826 } else {
827 btrfs_err(info, "unrecognized space_cache value %s",
828 args[0].from);
829 ret = -EINVAL;
830 goto out;
831 }
832 break;
833 case Opt_rescan_uuid_tree:
834 btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE);
835 break;
836 case Opt_no_space_cache:
837 if (btrfs_test_opt(info, SPACE_CACHE)) {
838 btrfs_clear_and_info(info, SPACE_CACHE,
839 "disabling disk space caching");
840 }
841 if (btrfs_test_opt(info, FREE_SPACE_TREE)) {
842 btrfs_clear_and_info(info, FREE_SPACE_TREE,
843 "disabling free space tree");
844 }
845 break;
846 case Opt_inode_cache:
847 btrfs_warn(info,
848 "the 'inode_cache' option is deprecated and will have no effect from 5.11");
849 btrfs_set_pending_and_info(info, INODE_MAP_CACHE,
850 "enabling inode map caching");
851 break;
852 case Opt_noinode_cache:
853 btrfs_clear_pending_and_info(info, INODE_MAP_CACHE,
854 "disabling inode map caching");
855 break;
856 case Opt_clear_cache:
857 btrfs_set_and_info(info, CLEAR_CACHE,
858 "force clearing of disk cache");
859 break;
860 case Opt_user_subvol_rm_allowed:
861 btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED);
862 break;
863 case Opt_enospc_debug:
864 btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG);
865 break;
866 case Opt_noenospc_debug:
867 btrfs_clear_opt(info->mount_opt, ENOSPC_DEBUG);
868 break;
869 case Opt_defrag:
870 btrfs_set_and_info(info, AUTO_DEFRAG,
871 "enabling auto defrag");
872 break;
873 case Opt_nodefrag:
874 btrfs_clear_and_info(info, AUTO_DEFRAG,
875 "disabling auto defrag");
876 break;
877 case Opt_recovery:
878 case Opt_usebackuproot:
879 btrfs_warn(info,
880 "'%s' is deprecated, use 'rescue=usebackuproot' instead",
881 token == Opt_recovery ? "recovery" :
882 "usebackuproot");
883 btrfs_info(info,
884 "trying to use backup root at mount time");
885 btrfs_set_opt(info->mount_opt, USEBACKUPROOT);
886 break;
887 case Opt_skip_balance:
888 btrfs_set_opt(info->mount_opt, SKIP_BALANCE);
889 break;
890 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
891 case Opt_check_integrity_including_extent_data:
892 btrfs_info(info,
893 "enabling check integrity including extent data");
894 btrfs_set_opt(info->mount_opt,
895 CHECK_INTEGRITY_INCLUDING_EXTENT_DATA);
896 btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
897 break;
898 case Opt_check_integrity:
899 btrfs_info(info, "enabling check integrity");
900 btrfs_set_opt(info->mount_opt, CHECK_INTEGRITY);
901 break;
902 case Opt_check_integrity_print_mask:
903 ret = match_int(&args[0], &intarg);
904 if (ret) {
905 btrfs_err(info,
906 "unrecognized check_integrity_print_mask value %s",
907 args[0].from);
908 goto out;
909 }
910 info->check_integrity_print_mask = intarg;
911 btrfs_info(info, "check_integrity_print_mask 0x%x",
912 info->check_integrity_print_mask);
913 break;
914 #else
915 case Opt_check_integrity_including_extent_data:
916 case Opt_check_integrity:
917 case Opt_check_integrity_print_mask:
918 btrfs_err(info,
919 "support for check_integrity* not compiled in!");
920 ret = -EINVAL;
921 goto out;
922 #endif
923 case Opt_fatal_errors:
924 if (strcmp(args[0].from, "panic") == 0) {
925 btrfs_set_opt(info->mount_opt,
926 PANIC_ON_FATAL_ERROR);
927 } else if (strcmp(args[0].from, "bug") == 0) {
928 btrfs_clear_opt(info->mount_opt,
929 PANIC_ON_FATAL_ERROR);
930 } else {
931 btrfs_err(info, "unrecognized fatal_errors value %s",
932 args[0].from);
933 ret = -EINVAL;
934 goto out;
935 }
936 break;
937 case Opt_commit_interval:
938 intarg = 0;
939 ret = match_int(&args[0], &intarg);
940 if (ret) {
941 btrfs_err(info, "unrecognized commit_interval value %s",
942 args[0].from);
943 ret = -EINVAL;
944 goto out;
945 }
946 if (intarg == 0) {
947 btrfs_info(info,
948 "using default commit interval %us",
949 BTRFS_DEFAULT_COMMIT_INTERVAL);
950 intarg = BTRFS_DEFAULT_COMMIT_INTERVAL;
951 } else if (intarg > 300) {
952 btrfs_warn(info, "excessive commit interval %d",
953 intarg);
954 }
955 info->commit_interval = intarg;
956 break;
957 case Opt_rescue:
958 ret = parse_rescue_options(info, args[0].from);
959 if (ret < 0) {
960 btrfs_err(info, "unrecognized rescue value %s",
961 args[0].from);
962 goto out;
963 }
964 break;
965 #ifdef CONFIG_BTRFS_DEBUG
966 case Opt_fragment_all:
967 btrfs_info(info, "fragmenting all space");
968 btrfs_set_opt(info->mount_opt, FRAGMENT_DATA);
969 btrfs_set_opt(info->mount_opt, FRAGMENT_METADATA);
970 break;
971 case Opt_fragment_metadata:
972 btrfs_info(info, "fragmenting metadata");
973 btrfs_set_opt(info->mount_opt,
974 FRAGMENT_METADATA);
975 break;
976 case Opt_fragment_data:
977 btrfs_info(info, "fragmenting data");
978 btrfs_set_opt(info->mount_opt, FRAGMENT_DATA);
979 break;
980 #endif
981 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
982 case Opt_ref_verify:
983 btrfs_info(info, "doing ref verification");
984 btrfs_set_opt(info->mount_opt, REF_VERIFY);
985 break;
986 #endif
987 case Opt_err:
988 btrfs_err(info, "unrecognized mount option '%s'", p);
989 ret = -EINVAL;
990 goto out;
991 default:
992 break;
993 }
994 }
995 check:
996 /*
997 * Extra check for current option against current flag
998 */
999 if (btrfs_test_opt(info, NOLOGREPLAY) && !(new_flags & SB_RDONLY)) {
1000 btrfs_err(info,
1001 "nologreplay must be used with ro mount option");
1002 ret = -EINVAL;
1003 }
1004 out:
1005 if (btrfs_fs_compat_ro(info, FREE_SPACE_TREE) &&
1006 !btrfs_test_opt(info, FREE_SPACE_TREE) &&
1007 !btrfs_test_opt(info, CLEAR_CACHE)) {
1008 btrfs_err(info, "cannot disable free space tree");
1009 ret = -EINVAL;
1010
1011 }
1012 if (!ret && btrfs_test_opt(info, SPACE_CACHE))
1013 btrfs_info(info, "disk space caching is enabled");
1014 if (!ret && btrfs_test_opt(info, FREE_SPACE_TREE))
1015 btrfs_info(info, "using free space tree");
1016 return ret;
1017 }
1018
1019 /*
1020 * Parse mount options that are required early in the mount process.
1021 *
1022 * All other options will be parsed on much later in the mount process and
1023 * only when we need to allocate a new super block.
1024 */
btrfs_parse_device_options(const char * options,fmode_t flags,void * holder)1025 static int btrfs_parse_device_options(const char *options, fmode_t flags,
1026 void *holder)
1027 {
1028 substring_t args[MAX_OPT_ARGS];
1029 char *device_name, *opts, *orig, *p;
1030 struct btrfs_device *device = NULL;
1031 int error = 0;
1032
1033 lockdep_assert_held(&uuid_mutex);
1034
1035 if (!options)
1036 return 0;
1037
1038 /*
1039 * strsep changes the string, duplicate it because btrfs_parse_options
1040 * gets called later
1041 */
1042 opts = kstrdup(options, GFP_KERNEL);
1043 if (!opts)
1044 return -ENOMEM;
1045 orig = opts;
1046
1047 while ((p = strsep(&opts, ",")) != NULL) {
1048 int token;
1049
1050 if (!*p)
1051 continue;
1052
1053 token = match_token(p, tokens, args);
1054 if (token == Opt_device) {
1055 device_name = match_strdup(&args[0]);
1056 if (!device_name) {
1057 error = -ENOMEM;
1058 goto out;
1059 }
1060 device = btrfs_scan_one_device(device_name, flags,
1061 holder);
1062 kfree(device_name);
1063 if (IS_ERR(device)) {
1064 error = PTR_ERR(device);
1065 goto out;
1066 }
1067 }
1068 }
1069
1070 out:
1071 kfree(orig);
1072 return error;
1073 }
1074
1075 /*
1076 * Parse mount options that are related to subvolume id
1077 *
1078 * The value is later passed to mount_subvol()
1079 */
btrfs_parse_subvol_options(const char * options,char ** subvol_name,u64 * subvol_objectid)1080 static int btrfs_parse_subvol_options(const char *options, char **subvol_name,
1081 u64 *subvol_objectid)
1082 {
1083 substring_t args[MAX_OPT_ARGS];
1084 char *opts, *orig, *p;
1085 int error = 0;
1086 u64 subvolid;
1087
1088 if (!options)
1089 return 0;
1090
1091 /*
1092 * strsep changes the string, duplicate it because
1093 * btrfs_parse_device_options gets called later
1094 */
1095 opts = kstrdup(options, GFP_KERNEL);
1096 if (!opts)
1097 return -ENOMEM;
1098 orig = opts;
1099
1100 while ((p = strsep(&opts, ",")) != NULL) {
1101 int token;
1102 if (!*p)
1103 continue;
1104
1105 token = match_token(p, tokens, args);
1106 switch (token) {
1107 case Opt_subvol:
1108 kfree(*subvol_name);
1109 *subvol_name = match_strdup(&args[0]);
1110 if (!*subvol_name) {
1111 error = -ENOMEM;
1112 goto out;
1113 }
1114 break;
1115 case Opt_subvolid:
1116 error = match_u64(&args[0], &subvolid);
1117 if (error)
1118 goto out;
1119
1120 /* we want the original fs_tree */
1121 if (subvolid == 0)
1122 subvolid = BTRFS_FS_TREE_OBJECTID;
1123
1124 *subvol_objectid = subvolid;
1125 break;
1126 default:
1127 break;
1128 }
1129 }
1130
1131 out:
1132 kfree(orig);
1133 return error;
1134 }
1135
btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info * fs_info,u64 subvol_objectid)1136 char *btrfs_get_subvol_name_from_objectid(struct btrfs_fs_info *fs_info,
1137 u64 subvol_objectid)
1138 {
1139 struct btrfs_root *root = fs_info->tree_root;
1140 struct btrfs_root *fs_root = NULL;
1141 struct btrfs_root_ref *root_ref;
1142 struct btrfs_inode_ref *inode_ref;
1143 struct btrfs_key key;
1144 struct btrfs_path *path = NULL;
1145 char *name = NULL, *ptr;
1146 u64 dirid;
1147 int len;
1148 int ret;
1149
1150 path = btrfs_alloc_path();
1151 if (!path) {
1152 ret = -ENOMEM;
1153 goto err;
1154 }
1155 path->leave_spinning = 1;
1156
1157 name = kmalloc(PATH_MAX, GFP_KERNEL);
1158 if (!name) {
1159 ret = -ENOMEM;
1160 goto err;
1161 }
1162 ptr = name + PATH_MAX - 1;
1163 ptr[0] = '\0';
1164
1165 /*
1166 * Walk up the subvolume trees in the tree of tree roots by root
1167 * backrefs until we hit the top-level subvolume.
1168 */
1169 while (subvol_objectid != BTRFS_FS_TREE_OBJECTID) {
1170 key.objectid = subvol_objectid;
1171 key.type = BTRFS_ROOT_BACKREF_KEY;
1172 key.offset = (u64)-1;
1173
1174 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1175 if (ret < 0) {
1176 goto err;
1177 } else if (ret > 0) {
1178 ret = btrfs_previous_item(root, path, subvol_objectid,
1179 BTRFS_ROOT_BACKREF_KEY);
1180 if (ret < 0) {
1181 goto err;
1182 } else if (ret > 0) {
1183 ret = -ENOENT;
1184 goto err;
1185 }
1186 }
1187
1188 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1189 subvol_objectid = key.offset;
1190
1191 root_ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
1192 struct btrfs_root_ref);
1193 len = btrfs_root_ref_name_len(path->nodes[0], root_ref);
1194 ptr -= len + 1;
1195 if (ptr < name) {
1196 ret = -ENAMETOOLONG;
1197 goto err;
1198 }
1199 read_extent_buffer(path->nodes[0], ptr + 1,
1200 (unsigned long)(root_ref + 1), len);
1201 ptr[0] = '/';
1202 dirid = btrfs_root_ref_dirid(path->nodes[0], root_ref);
1203 btrfs_release_path(path);
1204
1205 fs_root = btrfs_get_fs_root(fs_info, subvol_objectid, true);
1206 if (IS_ERR(fs_root)) {
1207 ret = PTR_ERR(fs_root);
1208 fs_root = NULL;
1209 goto err;
1210 }
1211
1212 /*
1213 * Walk up the filesystem tree by inode refs until we hit the
1214 * root directory.
1215 */
1216 while (dirid != BTRFS_FIRST_FREE_OBJECTID) {
1217 key.objectid = dirid;
1218 key.type = BTRFS_INODE_REF_KEY;
1219 key.offset = (u64)-1;
1220
1221 ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
1222 if (ret < 0) {
1223 goto err;
1224 } else if (ret > 0) {
1225 ret = btrfs_previous_item(fs_root, path, dirid,
1226 BTRFS_INODE_REF_KEY);
1227 if (ret < 0) {
1228 goto err;
1229 } else if (ret > 0) {
1230 ret = -ENOENT;
1231 goto err;
1232 }
1233 }
1234
1235 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1236 dirid = key.offset;
1237
1238 inode_ref = btrfs_item_ptr(path->nodes[0],
1239 path->slots[0],
1240 struct btrfs_inode_ref);
1241 len = btrfs_inode_ref_name_len(path->nodes[0],
1242 inode_ref);
1243 ptr -= len + 1;
1244 if (ptr < name) {
1245 ret = -ENAMETOOLONG;
1246 goto err;
1247 }
1248 read_extent_buffer(path->nodes[0], ptr + 1,
1249 (unsigned long)(inode_ref + 1), len);
1250 ptr[0] = '/';
1251 btrfs_release_path(path);
1252 }
1253 btrfs_put_root(fs_root);
1254 fs_root = NULL;
1255 }
1256
1257 btrfs_free_path(path);
1258 if (ptr == name + PATH_MAX - 1) {
1259 name[0] = '/';
1260 name[1] = '\0';
1261 } else {
1262 memmove(name, ptr, name + PATH_MAX - ptr);
1263 }
1264 return name;
1265
1266 err:
1267 btrfs_put_root(fs_root);
1268 btrfs_free_path(path);
1269 kfree(name);
1270 return ERR_PTR(ret);
1271 }
1272
get_default_subvol_objectid(struct btrfs_fs_info * fs_info,u64 * objectid)1273 static int get_default_subvol_objectid(struct btrfs_fs_info *fs_info, u64 *objectid)
1274 {
1275 struct btrfs_root *root = fs_info->tree_root;
1276 struct btrfs_dir_item *di;
1277 struct btrfs_path *path;
1278 struct btrfs_key location;
1279 u64 dir_id;
1280
1281 path = btrfs_alloc_path();
1282 if (!path)
1283 return -ENOMEM;
1284 path->leave_spinning = 1;
1285
1286 /*
1287 * Find the "default" dir item which points to the root item that we
1288 * will mount by default if we haven't been given a specific subvolume
1289 * to mount.
1290 */
1291 dir_id = btrfs_super_root_dir(fs_info->super_copy);
1292 di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0);
1293 if (IS_ERR(di)) {
1294 btrfs_free_path(path);
1295 return PTR_ERR(di);
1296 }
1297 if (!di) {
1298 /*
1299 * Ok the default dir item isn't there. This is weird since
1300 * it's always been there, but don't freak out, just try and
1301 * mount the top-level subvolume.
1302 */
1303 btrfs_free_path(path);
1304 *objectid = BTRFS_FS_TREE_OBJECTID;
1305 return 0;
1306 }
1307
1308 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
1309 btrfs_free_path(path);
1310 *objectid = location.objectid;
1311 return 0;
1312 }
1313
btrfs_fill_super(struct super_block * sb,struct btrfs_fs_devices * fs_devices,void * data)1314 static int btrfs_fill_super(struct super_block *sb,
1315 struct btrfs_fs_devices *fs_devices,
1316 void *data)
1317 {
1318 struct inode *inode;
1319 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1320 int err;
1321
1322 sb->s_maxbytes = MAX_LFS_FILESIZE;
1323 sb->s_magic = BTRFS_SUPER_MAGIC;
1324 sb->s_op = &btrfs_super_ops;
1325 sb->s_d_op = &btrfs_dentry_operations;
1326 sb->s_export_op = &btrfs_export_ops;
1327 sb->s_xattr = btrfs_xattr_handlers;
1328 sb->s_time_gran = 1;
1329 #ifdef CONFIG_BTRFS_FS_POSIX_ACL
1330 sb->s_flags |= SB_POSIXACL;
1331 #endif
1332 sb->s_flags |= SB_I_VERSION;
1333 sb->s_iflags |= SB_I_CGROUPWB;
1334
1335 err = super_setup_bdi(sb);
1336 if (err) {
1337 btrfs_err(fs_info, "super_setup_bdi failed");
1338 return err;
1339 }
1340
1341 err = open_ctree(sb, fs_devices, (char *)data);
1342 if (err) {
1343 btrfs_err(fs_info, "open_ctree failed");
1344 return err;
1345 }
1346
1347 inode = btrfs_iget(sb, BTRFS_FIRST_FREE_OBJECTID, fs_info->fs_root);
1348 if (IS_ERR(inode)) {
1349 err = PTR_ERR(inode);
1350 goto fail_close;
1351 }
1352
1353 sb->s_root = d_make_root(inode);
1354 if (!sb->s_root) {
1355 err = -ENOMEM;
1356 goto fail_close;
1357 }
1358
1359 cleancache_init_fs(sb);
1360 sb->s_flags |= SB_ACTIVE;
1361 return 0;
1362
1363 fail_close:
1364 close_ctree(fs_info);
1365 return err;
1366 }
1367
btrfs_sync_fs(struct super_block * sb,int wait)1368 int btrfs_sync_fs(struct super_block *sb, int wait)
1369 {
1370 struct btrfs_trans_handle *trans;
1371 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1372 struct btrfs_root *root = fs_info->tree_root;
1373
1374 trace_btrfs_sync_fs(fs_info, wait);
1375
1376 if (!wait) {
1377 filemap_flush(fs_info->btree_inode->i_mapping);
1378 return 0;
1379 }
1380
1381 btrfs_wait_ordered_roots(fs_info, U64_MAX, 0, (u64)-1);
1382
1383 trans = btrfs_attach_transaction_barrier(root);
1384 if (IS_ERR(trans)) {
1385 /* no transaction, don't bother */
1386 if (PTR_ERR(trans) == -ENOENT) {
1387 /*
1388 * Exit unless we have some pending changes
1389 * that need to go through commit
1390 */
1391 if (fs_info->pending_changes == 0)
1392 return 0;
1393 /*
1394 * A non-blocking test if the fs is frozen. We must not
1395 * start a new transaction here otherwise a deadlock
1396 * happens. The pending operations are delayed to the
1397 * next commit after thawing.
1398 */
1399 if (sb_start_write_trylock(sb))
1400 sb_end_write(sb);
1401 else
1402 return 0;
1403 trans = btrfs_start_transaction(root, 0);
1404 }
1405 if (IS_ERR(trans))
1406 return PTR_ERR(trans);
1407 }
1408 return btrfs_commit_transaction(trans);
1409 }
1410
btrfs_show_options(struct seq_file * seq,struct dentry * dentry)1411 static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry)
1412 {
1413 struct btrfs_fs_info *info = btrfs_sb(dentry->d_sb);
1414 const char *compress_type;
1415 const char *subvol_name;
1416
1417 if (btrfs_test_opt(info, DEGRADED))
1418 seq_puts(seq, ",degraded");
1419 if (btrfs_test_opt(info, NODATASUM))
1420 seq_puts(seq, ",nodatasum");
1421 if (btrfs_test_opt(info, NODATACOW))
1422 seq_puts(seq, ",nodatacow");
1423 if (btrfs_test_opt(info, NOBARRIER))
1424 seq_puts(seq, ",nobarrier");
1425 if (info->max_inline != BTRFS_DEFAULT_MAX_INLINE)
1426 seq_printf(seq, ",max_inline=%llu", info->max_inline);
1427 if (info->thread_pool_size != min_t(unsigned long,
1428 num_online_cpus() + 2, 8))
1429 seq_printf(seq, ",thread_pool=%u", info->thread_pool_size);
1430 if (btrfs_test_opt(info, COMPRESS)) {
1431 compress_type = btrfs_compress_type2str(info->compress_type);
1432 if (btrfs_test_opt(info, FORCE_COMPRESS))
1433 seq_printf(seq, ",compress-force=%s", compress_type);
1434 else
1435 seq_printf(seq, ",compress=%s", compress_type);
1436 if (info->compress_level)
1437 seq_printf(seq, ":%d", info->compress_level);
1438 }
1439 if (btrfs_test_opt(info, NOSSD))
1440 seq_puts(seq, ",nossd");
1441 if (btrfs_test_opt(info, SSD_SPREAD))
1442 seq_puts(seq, ",ssd_spread");
1443 else if (btrfs_test_opt(info, SSD))
1444 seq_puts(seq, ",ssd");
1445 if (btrfs_test_opt(info, NOTREELOG))
1446 seq_puts(seq, ",notreelog");
1447 if (btrfs_test_opt(info, NOLOGREPLAY))
1448 seq_puts(seq, ",rescue=nologreplay");
1449 if (btrfs_test_opt(info, FLUSHONCOMMIT))
1450 seq_puts(seq, ",flushoncommit");
1451 if (btrfs_test_opt(info, DISCARD_SYNC))
1452 seq_puts(seq, ",discard");
1453 if (btrfs_test_opt(info, DISCARD_ASYNC))
1454 seq_puts(seq, ",discard=async");
1455 if (!(info->sb->s_flags & SB_POSIXACL))
1456 seq_puts(seq, ",noacl");
1457 if (btrfs_test_opt(info, SPACE_CACHE))
1458 seq_puts(seq, ",space_cache");
1459 else if (btrfs_test_opt(info, FREE_SPACE_TREE))
1460 seq_puts(seq, ",space_cache=v2");
1461 else
1462 seq_puts(seq, ",nospace_cache");
1463 if (btrfs_test_opt(info, RESCAN_UUID_TREE))
1464 seq_puts(seq, ",rescan_uuid_tree");
1465 if (btrfs_test_opt(info, CLEAR_CACHE))
1466 seq_puts(seq, ",clear_cache");
1467 if (btrfs_test_opt(info, USER_SUBVOL_RM_ALLOWED))
1468 seq_puts(seq, ",user_subvol_rm_allowed");
1469 if (btrfs_test_opt(info, ENOSPC_DEBUG))
1470 seq_puts(seq, ",enospc_debug");
1471 if (btrfs_test_opt(info, AUTO_DEFRAG))
1472 seq_puts(seq, ",autodefrag");
1473 if (btrfs_test_opt(info, INODE_MAP_CACHE))
1474 seq_puts(seq, ",inode_cache");
1475 if (btrfs_test_opt(info, SKIP_BALANCE))
1476 seq_puts(seq, ",skip_balance");
1477 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
1478 if (btrfs_test_opt(info, CHECK_INTEGRITY_INCLUDING_EXTENT_DATA))
1479 seq_puts(seq, ",check_int_data");
1480 else if (btrfs_test_opt(info, CHECK_INTEGRITY))
1481 seq_puts(seq, ",check_int");
1482 if (info->check_integrity_print_mask)
1483 seq_printf(seq, ",check_int_print_mask=%d",
1484 info->check_integrity_print_mask);
1485 #endif
1486 if (info->metadata_ratio)
1487 seq_printf(seq, ",metadata_ratio=%u", info->metadata_ratio);
1488 if (btrfs_test_opt(info, PANIC_ON_FATAL_ERROR))
1489 seq_puts(seq, ",fatal_errors=panic");
1490 if (info->commit_interval != BTRFS_DEFAULT_COMMIT_INTERVAL)
1491 seq_printf(seq, ",commit=%u", info->commit_interval);
1492 #ifdef CONFIG_BTRFS_DEBUG
1493 if (btrfs_test_opt(info, FRAGMENT_DATA))
1494 seq_puts(seq, ",fragment=data");
1495 if (btrfs_test_opt(info, FRAGMENT_METADATA))
1496 seq_puts(seq, ",fragment=metadata");
1497 #endif
1498 if (btrfs_test_opt(info, REF_VERIFY))
1499 seq_puts(seq, ",ref_verify");
1500 seq_printf(seq, ",subvolid=%llu",
1501 BTRFS_I(d_inode(dentry))->root->root_key.objectid);
1502 subvol_name = btrfs_get_subvol_name_from_objectid(info,
1503 BTRFS_I(d_inode(dentry))->root->root_key.objectid);
1504 if (!IS_ERR(subvol_name)) {
1505 seq_puts(seq, ",subvol=");
1506 seq_escape(seq, subvol_name, " \t\n\\");
1507 kfree(subvol_name);
1508 }
1509 return 0;
1510 }
1511
btrfs_test_super(struct super_block * s,void * data)1512 static int btrfs_test_super(struct super_block *s, void *data)
1513 {
1514 struct btrfs_fs_info *p = data;
1515 struct btrfs_fs_info *fs_info = btrfs_sb(s);
1516
1517 return fs_info->fs_devices == p->fs_devices;
1518 }
1519
btrfs_set_super(struct super_block * s,void * data)1520 static int btrfs_set_super(struct super_block *s, void *data)
1521 {
1522 int err = set_anon_super(s, data);
1523 if (!err)
1524 s->s_fs_info = data;
1525 return err;
1526 }
1527
1528 /*
1529 * subvolumes are identified by ino 256
1530 */
is_subvolume_inode(struct inode * inode)1531 static inline int is_subvolume_inode(struct inode *inode)
1532 {
1533 if (inode && inode->i_ino == BTRFS_FIRST_FREE_OBJECTID)
1534 return 1;
1535 return 0;
1536 }
1537
mount_subvol(const char * subvol_name,u64 subvol_objectid,struct vfsmount * mnt)1538 static struct dentry *mount_subvol(const char *subvol_name, u64 subvol_objectid,
1539 struct vfsmount *mnt)
1540 {
1541 struct dentry *root;
1542 int ret;
1543
1544 if (!subvol_name) {
1545 if (!subvol_objectid) {
1546 ret = get_default_subvol_objectid(btrfs_sb(mnt->mnt_sb),
1547 &subvol_objectid);
1548 if (ret) {
1549 root = ERR_PTR(ret);
1550 goto out;
1551 }
1552 }
1553 subvol_name = btrfs_get_subvol_name_from_objectid(
1554 btrfs_sb(mnt->mnt_sb), subvol_objectid);
1555 if (IS_ERR(subvol_name)) {
1556 root = ERR_CAST(subvol_name);
1557 subvol_name = NULL;
1558 goto out;
1559 }
1560
1561 }
1562
1563 root = mount_subtree(mnt, subvol_name);
1564 /* mount_subtree() drops our reference on the vfsmount. */
1565 mnt = NULL;
1566
1567 if (!IS_ERR(root)) {
1568 struct super_block *s = root->d_sb;
1569 struct btrfs_fs_info *fs_info = btrfs_sb(s);
1570 struct inode *root_inode = d_inode(root);
1571 u64 root_objectid = BTRFS_I(root_inode)->root->root_key.objectid;
1572
1573 ret = 0;
1574 if (!is_subvolume_inode(root_inode)) {
1575 btrfs_err(fs_info, "'%s' is not a valid subvolume",
1576 subvol_name);
1577 ret = -EINVAL;
1578 }
1579 if (subvol_objectid && root_objectid != subvol_objectid) {
1580 /*
1581 * This will also catch a race condition where a
1582 * subvolume which was passed by ID is renamed and
1583 * another subvolume is renamed over the old location.
1584 */
1585 btrfs_err(fs_info,
1586 "subvol '%s' does not match subvolid %llu",
1587 subvol_name, subvol_objectid);
1588 ret = -EINVAL;
1589 }
1590 if (ret) {
1591 dput(root);
1592 root = ERR_PTR(ret);
1593 deactivate_locked_super(s);
1594 }
1595 }
1596
1597 out:
1598 mntput(mnt);
1599 kfree(subvol_name);
1600 return root;
1601 }
1602
1603 /*
1604 * Find a superblock for the given device / mount point.
1605 *
1606 * Note: This is based on mount_bdev from fs/super.c with a few additions
1607 * for multiple device setup. Make sure to keep it in sync.
1608 */
btrfs_mount_root(struct file_system_type * fs_type,int flags,const char * device_name,void * data)1609 static struct dentry *btrfs_mount_root(struct file_system_type *fs_type,
1610 int flags, const char *device_name, void *data)
1611 {
1612 struct block_device *bdev = NULL;
1613 struct super_block *s;
1614 struct btrfs_device *device = NULL;
1615 struct btrfs_fs_devices *fs_devices = NULL;
1616 struct btrfs_fs_info *fs_info = NULL;
1617 void *new_sec_opts = NULL;
1618 fmode_t mode = FMODE_READ;
1619 int error = 0;
1620
1621 if (!(flags & SB_RDONLY))
1622 mode |= FMODE_WRITE;
1623
1624 if (data) {
1625 error = security_sb_eat_lsm_opts(data, &new_sec_opts);
1626 if (error)
1627 return ERR_PTR(error);
1628 }
1629
1630 /*
1631 * Setup a dummy root and fs_info for test/set super. This is because
1632 * we don't actually fill this stuff out until open_ctree, but we need
1633 * then open_ctree will properly initialize the file system specific
1634 * settings later. btrfs_init_fs_info initializes the static elements
1635 * of the fs_info (locks and such) to make cleanup easier if we find a
1636 * superblock with our given fs_devices later on at sget() time.
1637 */
1638 fs_info = kvzalloc(sizeof(struct btrfs_fs_info), GFP_KERNEL);
1639 if (!fs_info) {
1640 error = -ENOMEM;
1641 goto error_sec_opts;
1642 }
1643 btrfs_init_fs_info(fs_info);
1644
1645 fs_info->super_copy = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
1646 fs_info->super_for_commit = kzalloc(BTRFS_SUPER_INFO_SIZE, GFP_KERNEL);
1647 if (!fs_info->super_copy || !fs_info->super_for_commit) {
1648 error = -ENOMEM;
1649 goto error_fs_info;
1650 }
1651
1652 mutex_lock(&uuid_mutex);
1653 error = btrfs_parse_device_options(data, mode, fs_type);
1654 if (error) {
1655 mutex_unlock(&uuid_mutex);
1656 goto error_fs_info;
1657 }
1658
1659 device = btrfs_scan_one_device(device_name, mode, fs_type);
1660 if (IS_ERR(device)) {
1661 mutex_unlock(&uuid_mutex);
1662 error = PTR_ERR(device);
1663 goto error_fs_info;
1664 }
1665
1666 fs_devices = device->fs_devices;
1667 fs_info->fs_devices = fs_devices;
1668
1669 error = btrfs_open_devices(fs_devices, mode, fs_type);
1670 mutex_unlock(&uuid_mutex);
1671 if (error)
1672 goto error_fs_info;
1673
1674 if (!(flags & SB_RDONLY) && fs_devices->rw_devices == 0) {
1675 error = -EACCES;
1676 goto error_close_devices;
1677 }
1678
1679 bdev = fs_devices->latest_bdev;
1680 s = sget(fs_type, btrfs_test_super, btrfs_set_super, flags | SB_NOSEC,
1681 fs_info);
1682 if (IS_ERR(s)) {
1683 error = PTR_ERR(s);
1684 goto error_close_devices;
1685 }
1686
1687 if (s->s_root) {
1688 btrfs_close_devices(fs_devices);
1689 btrfs_free_fs_info(fs_info);
1690 if ((flags ^ s->s_flags) & SB_RDONLY)
1691 error = -EBUSY;
1692 } else {
1693 snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
1694 btrfs_sb(s)->bdev_holder = fs_type;
1695 error = btrfs_fill_super(s, fs_devices, data);
1696 }
1697 if (!error)
1698 error = security_sb_set_mnt_opts(s, new_sec_opts, 0, NULL);
1699 security_free_mnt_opts(&new_sec_opts);
1700 if (error) {
1701 deactivate_locked_super(s);
1702 return ERR_PTR(error);
1703 }
1704
1705 return dget(s->s_root);
1706
1707 error_close_devices:
1708 btrfs_close_devices(fs_devices);
1709 error_fs_info:
1710 btrfs_free_fs_info(fs_info);
1711 error_sec_opts:
1712 security_free_mnt_opts(&new_sec_opts);
1713 return ERR_PTR(error);
1714 }
1715
1716 /*
1717 * Mount function which is called by VFS layer.
1718 *
1719 * In order to allow mounting a subvolume directly, btrfs uses mount_subtree()
1720 * which needs vfsmount* of device's root (/). This means device's root has to
1721 * be mounted internally in any case.
1722 *
1723 * Operation flow:
1724 * 1. Parse subvol id related options for later use in mount_subvol().
1725 *
1726 * 2. Mount device's root (/) by calling vfs_kern_mount().
1727 *
1728 * NOTE: vfs_kern_mount() is used by VFS to call btrfs_mount() in the
1729 * first place. In order to avoid calling btrfs_mount() again, we use
1730 * different file_system_type which is not registered to VFS by
1731 * register_filesystem() (btrfs_root_fs_type). As a result,
1732 * btrfs_mount_root() is called. The return value will be used by
1733 * mount_subtree() in mount_subvol().
1734 *
1735 * 3. Call mount_subvol() to get the dentry of subvolume. Since there is
1736 * "btrfs subvolume set-default", mount_subvol() is called always.
1737 */
btrfs_mount(struct file_system_type * fs_type,int flags,const char * device_name,void * data)1738 static struct dentry *btrfs_mount(struct file_system_type *fs_type, int flags,
1739 const char *device_name, void *data)
1740 {
1741 struct vfsmount *mnt_root;
1742 struct dentry *root;
1743 char *subvol_name = NULL;
1744 u64 subvol_objectid = 0;
1745 int error = 0;
1746
1747 error = btrfs_parse_subvol_options(data, &subvol_name,
1748 &subvol_objectid);
1749 if (error) {
1750 kfree(subvol_name);
1751 return ERR_PTR(error);
1752 }
1753
1754 /* mount device's root (/) */
1755 mnt_root = vfs_kern_mount(&btrfs_root_fs_type, flags, device_name, data);
1756 if (PTR_ERR_OR_ZERO(mnt_root) == -EBUSY) {
1757 if (flags & SB_RDONLY) {
1758 mnt_root = vfs_kern_mount(&btrfs_root_fs_type,
1759 flags & ~SB_RDONLY, device_name, data);
1760 } else {
1761 mnt_root = vfs_kern_mount(&btrfs_root_fs_type,
1762 flags | SB_RDONLY, device_name, data);
1763 if (IS_ERR(mnt_root)) {
1764 root = ERR_CAST(mnt_root);
1765 kfree(subvol_name);
1766 goto out;
1767 }
1768
1769 down_write(&mnt_root->mnt_sb->s_umount);
1770 error = btrfs_remount(mnt_root->mnt_sb, &flags, NULL);
1771 up_write(&mnt_root->mnt_sb->s_umount);
1772 if (error < 0) {
1773 root = ERR_PTR(error);
1774 mntput(mnt_root);
1775 kfree(subvol_name);
1776 goto out;
1777 }
1778 }
1779 }
1780 if (IS_ERR(mnt_root)) {
1781 root = ERR_CAST(mnt_root);
1782 kfree(subvol_name);
1783 goto out;
1784 }
1785
1786 /* mount_subvol() will free subvol_name and mnt_root */
1787 root = mount_subvol(subvol_name, subvol_objectid, mnt_root);
1788
1789 out:
1790 return root;
1791 }
1792
btrfs_resize_thread_pool(struct btrfs_fs_info * fs_info,u32 new_pool_size,u32 old_pool_size)1793 static void btrfs_resize_thread_pool(struct btrfs_fs_info *fs_info,
1794 u32 new_pool_size, u32 old_pool_size)
1795 {
1796 if (new_pool_size == old_pool_size)
1797 return;
1798
1799 fs_info->thread_pool_size = new_pool_size;
1800
1801 btrfs_info(fs_info, "resize thread pool %d -> %d",
1802 old_pool_size, new_pool_size);
1803
1804 btrfs_workqueue_set_max(fs_info->workers, new_pool_size);
1805 btrfs_workqueue_set_max(fs_info->delalloc_workers, new_pool_size);
1806 btrfs_workqueue_set_max(fs_info->caching_workers, new_pool_size);
1807 btrfs_workqueue_set_max(fs_info->endio_workers, new_pool_size);
1808 btrfs_workqueue_set_max(fs_info->endio_meta_workers, new_pool_size);
1809 btrfs_workqueue_set_max(fs_info->endio_meta_write_workers,
1810 new_pool_size);
1811 btrfs_workqueue_set_max(fs_info->endio_write_workers, new_pool_size);
1812 btrfs_workqueue_set_max(fs_info->endio_freespace_worker, new_pool_size);
1813 btrfs_workqueue_set_max(fs_info->delayed_workers, new_pool_size);
1814 btrfs_workqueue_set_max(fs_info->readahead_workers, new_pool_size);
1815 btrfs_workqueue_set_max(fs_info->scrub_wr_completion_workers,
1816 new_pool_size);
1817 }
1818
btrfs_remount_begin(struct btrfs_fs_info * fs_info,unsigned long old_opts,int flags)1819 static inline void btrfs_remount_begin(struct btrfs_fs_info *fs_info,
1820 unsigned long old_opts, int flags)
1821 {
1822 if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) &&
1823 (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) ||
1824 (flags & SB_RDONLY))) {
1825 /* wait for any defraggers to finish */
1826 wait_event(fs_info->transaction_wait,
1827 (atomic_read(&fs_info->defrag_running) == 0));
1828 if (flags & SB_RDONLY)
1829 sync_filesystem(fs_info->sb);
1830 }
1831 }
1832
btrfs_remount_cleanup(struct btrfs_fs_info * fs_info,unsigned long old_opts)1833 static inline void btrfs_remount_cleanup(struct btrfs_fs_info *fs_info,
1834 unsigned long old_opts)
1835 {
1836 /*
1837 * We need to cleanup all defragable inodes if the autodefragment is
1838 * close or the filesystem is read only.
1839 */
1840 if (btrfs_raw_test_opt(old_opts, AUTO_DEFRAG) &&
1841 (!btrfs_raw_test_opt(fs_info->mount_opt, AUTO_DEFRAG) || sb_rdonly(fs_info->sb))) {
1842 btrfs_cleanup_defrag_inodes(fs_info);
1843 }
1844
1845 /* If we toggled discard async */
1846 if (!btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) &&
1847 btrfs_test_opt(fs_info, DISCARD_ASYNC))
1848 btrfs_discard_resume(fs_info);
1849 else if (btrfs_raw_test_opt(old_opts, DISCARD_ASYNC) &&
1850 !btrfs_test_opt(fs_info, DISCARD_ASYNC))
1851 btrfs_discard_cleanup(fs_info);
1852 }
1853
btrfs_remount(struct super_block * sb,int * flags,char * data)1854 static int btrfs_remount(struct super_block *sb, int *flags, char *data)
1855 {
1856 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
1857 struct btrfs_root *root = fs_info->tree_root;
1858 unsigned old_flags = sb->s_flags;
1859 unsigned long old_opts = fs_info->mount_opt;
1860 unsigned long old_compress_type = fs_info->compress_type;
1861 u64 old_max_inline = fs_info->max_inline;
1862 u32 old_thread_pool_size = fs_info->thread_pool_size;
1863 u32 old_metadata_ratio = fs_info->metadata_ratio;
1864 int ret;
1865
1866 sync_filesystem(sb);
1867 set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state);
1868
1869 if (data) {
1870 void *new_sec_opts = NULL;
1871
1872 ret = security_sb_eat_lsm_opts(data, &new_sec_opts);
1873 if (!ret)
1874 ret = security_sb_remount(sb, new_sec_opts);
1875 security_free_mnt_opts(&new_sec_opts);
1876 if (ret)
1877 goto restore;
1878 }
1879
1880 ret = btrfs_parse_options(fs_info, data, *flags);
1881 if (ret)
1882 goto restore;
1883
1884 btrfs_remount_begin(fs_info, old_opts, *flags);
1885 btrfs_resize_thread_pool(fs_info,
1886 fs_info->thread_pool_size, old_thread_pool_size);
1887
1888 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))
1889 goto out;
1890
1891 if (*flags & SB_RDONLY) {
1892 /*
1893 * this also happens on 'umount -rf' or on shutdown, when
1894 * the filesystem is busy.
1895 */
1896 cancel_work_sync(&fs_info->async_reclaim_work);
1897 cancel_work_sync(&fs_info->async_data_reclaim_work);
1898
1899 btrfs_discard_cleanup(fs_info);
1900
1901 /* wait for the uuid_scan task to finish */
1902 down(&fs_info->uuid_tree_rescan_sem);
1903 /* avoid complains from lockdep et al. */
1904 up(&fs_info->uuid_tree_rescan_sem);
1905
1906 sb->s_flags |= SB_RDONLY;
1907
1908 /*
1909 * Setting SB_RDONLY will put the cleaner thread to
1910 * sleep at the next loop if it's already active.
1911 * If it's already asleep, we'll leave unused block
1912 * groups on disk until we're mounted read-write again
1913 * unless we clean them up here.
1914 */
1915 btrfs_delete_unused_bgs(fs_info);
1916
1917 btrfs_dev_replace_suspend_for_unmount(fs_info);
1918 btrfs_scrub_cancel(fs_info);
1919 btrfs_pause_balance(fs_info);
1920
1921 /*
1922 * Pause the qgroup rescan worker if it is running. We don't want
1923 * it to be still running after we are in RO mode, as after that,
1924 * by the time we unmount, it might have left a transaction open,
1925 * so we would leak the transaction and/or crash.
1926 */
1927 btrfs_qgroup_wait_for_completion(fs_info, false);
1928
1929 ret = btrfs_commit_super(fs_info);
1930 if (ret)
1931 goto restore;
1932 } else {
1933 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) {
1934 btrfs_err(fs_info,
1935 "Remounting read-write after error is not allowed");
1936 ret = -EINVAL;
1937 goto restore;
1938 }
1939 if (fs_info->fs_devices->rw_devices == 0) {
1940 ret = -EACCES;
1941 goto restore;
1942 }
1943
1944 if (!btrfs_check_rw_degradable(fs_info, NULL)) {
1945 btrfs_warn(fs_info,
1946 "too many missing devices, writable remount is not allowed");
1947 ret = -EACCES;
1948 goto restore;
1949 }
1950
1951 if (btrfs_super_log_root(fs_info->super_copy) != 0) {
1952 btrfs_warn(fs_info,
1953 "mount required to replay tree-log, cannot remount read-write");
1954 ret = -EINVAL;
1955 goto restore;
1956 }
1957
1958 ret = btrfs_cleanup_fs_roots(fs_info);
1959 if (ret)
1960 goto restore;
1961
1962 /* recover relocation */
1963 mutex_lock(&fs_info->cleaner_mutex);
1964 ret = btrfs_recover_relocation(root);
1965 mutex_unlock(&fs_info->cleaner_mutex);
1966 if (ret)
1967 goto restore;
1968
1969 ret = btrfs_resume_balance_async(fs_info);
1970 if (ret)
1971 goto restore;
1972
1973 ret = btrfs_resume_dev_replace_async(fs_info);
1974 if (ret) {
1975 btrfs_warn(fs_info, "failed to resume dev_replace");
1976 goto restore;
1977 }
1978
1979 btrfs_qgroup_rescan_resume(fs_info);
1980
1981 if (!fs_info->uuid_root) {
1982 btrfs_info(fs_info, "creating UUID tree");
1983 ret = btrfs_create_uuid_tree(fs_info);
1984 if (ret) {
1985 btrfs_warn(fs_info,
1986 "failed to create the UUID tree %d",
1987 ret);
1988 goto restore;
1989 }
1990 }
1991 sb->s_flags &= ~SB_RDONLY;
1992
1993 set_bit(BTRFS_FS_OPEN, &fs_info->flags);
1994 }
1995 out:
1996 /*
1997 * We need to set SB_I_VERSION here otherwise it'll get cleared by VFS,
1998 * since the absence of the flag means it can be toggled off by remount.
1999 */
2000 *flags |= SB_I_VERSION;
2001
2002 wake_up_process(fs_info->transaction_kthread);
2003 btrfs_remount_cleanup(fs_info, old_opts);
2004 clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state);
2005
2006 return 0;
2007
2008 restore:
2009 /* We've hit an error - don't reset SB_RDONLY */
2010 if (sb_rdonly(sb))
2011 old_flags |= SB_RDONLY;
2012 sb->s_flags = old_flags;
2013 fs_info->mount_opt = old_opts;
2014 fs_info->compress_type = old_compress_type;
2015 fs_info->max_inline = old_max_inline;
2016 btrfs_resize_thread_pool(fs_info,
2017 old_thread_pool_size, fs_info->thread_pool_size);
2018 fs_info->metadata_ratio = old_metadata_ratio;
2019 btrfs_remount_cleanup(fs_info, old_opts);
2020 clear_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state);
2021
2022 return ret;
2023 }
2024
2025 /* Used to sort the devices by max_avail(descending sort) */
btrfs_cmp_device_free_bytes(const void * dev_info1,const void * dev_info2)2026 static inline int btrfs_cmp_device_free_bytes(const void *dev_info1,
2027 const void *dev_info2)
2028 {
2029 if (((struct btrfs_device_info *)dev_info1)->max_avail >
2030 ((struct btrfs_device_info *)dev_info2)->max_avail)
2031 return -1;
2032 else if (((struct btrfs_device_info *)dev_info1)->max_avail <
2033 ((struct btrfs_device_info *)dev_info2)->max_avail)
2034 return 1;
2035 else
2036 return 0;
2037 }
2038
2039 /*
2040 * sort the devices by max_avail, in which max free extent size of each device
2041 * is stored.(Descending Sort)
2042 */
btrfs_descending_sort_devices(struct btrfs_device_info * devices,size_t nr_devices)2043 static inline void btrfs_descending_sort_devices(
2044 struct btrfs_device_info *devices,
2045 size_t nr_devices)
2046 {
2047 sort(devices, nr_devices, sizeof(struct btrfs_device_info),
2048 btrfs_cmp_device_free_bytes, NULL);
2049 }
2050
2051 /*
2052 * The helper to calc the free space on the devices that can be used to store
2053 * file data.
2054 */
btrfs_calc_avail_data_space(struct btrfs_fs_info * fs_info,u64 * free_bytes)2055 static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info,
2056 u64 *free_bytes)
2057 {
2058 struct btrfs_device_info *devices_info;
2059 struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2060 struct btrfs_device *device;
2061 u64 type;
2062 u64 avail_space;
2063 u64 min_stripe_size;
2064 int num_stripes = 1;
2065 int i = 0, nr_devices;
2066 const struct btrfs_raid_attr *rattr;
2067
2068 /*
2069 * We aren't under the device list lock, so this is racy-ish, but good
2070 * enough for our purposes.
2071 */
2072 nr_devices = fs_info->fs_devices->open_devices;
2073 if (!nr_devices) {
2074 smp_mb();
2075 nr_devices = fs_info->fs_devices->open_devices;
2076 ASSERT(nr_devices);
2077 if (!nr_devices) {
2078 *free_bytes = 0;
2079 return 0;
2080 }
2081 }
2082
2083 devices_info = kmalloc_array(nr_devices, sizeof(*devices_info),
2084 GFP_KERNEL);
2085 if (!devices_info)
2086 return -ENOMEM;
2087
2088 /* calc min stripe number for data space allocation */
2089 type = btrfs_data_alloc_profile(fs_info);
2090 rattr = &btrfs_raid_array[btrfs_bg_flags_to_raid_index(type)];
2091
2092 if (type & BTRFS_BLOCK_GROUP_RAID0)
2093 num_stripes = nr_devices;
2094 else if (type & BTRFS_BLOCK_GROUP_RAID1)
2095 num_stripes = 2;
2096 else if (type & BTRFS_BLOCK_GROUP_RAID1C3)
2097 num_stripes = 3;
2098 else if (type & BTRFS_BLOCK_GROUP_RAID1C4)
2099 num_stripes = 4;
2100 else if (type & BTRFS_BLOCK_GROUP_RAID10)
2101 num_stripes = 4;
2102
2103 /* Adjust for more than 1 stripe per device */
2104 min_stripe_size = rattr->dev_stripes * BTRFS_STRIPE_LEN;
2105
2106 rcu_read_lock();
2107 list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
2108 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA,
2109 &device->dev_state) ||
2110 !device->bdev ||
2111 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state))
2112 continue;
2113
2114 if (i >= nr_devices)
2115 break;
2116
2117 avail_space = device->total_bytes - device->bytes_used;
2118
2119 /* align with stripe_len */
2120 avail_space = rounddown(avail_space, BTRFS_STRIPE_LEN);
2121
2122 /*
2123 * In order to avoid overwriting the superblock on the drive,
2124 * btrfs starts at an offset of at least 1MB when doing chunk
2125 * allocation.
2126 *
2127 * This ensures we have at least min_stripe_size free space
2128 * after excluding 1MB.
2129 */
2130 if (avail_space <= SZ_1M + min_stripe_size)
2131 continue;
2132
2133 avail_space -= SZ_1M;
2134
2135 devices_info[i].dev = device;
2136 devices_info[i].max_avail = avail_space;
2137
2138 i++;
2139 }
2140 rcu_read_unlock();
2141
2142 nr_devices = i;
2143
2144 btrfs_descending_sort_devices(devices_info, nr_devices);
2145
2146 i = nr_devices - 1;
2147 avail_space = 0;
2148 while (nr_devices >= rattr->devs_min) {
2149 num_stripes = min(num_stripes, nr_devices);
2150
2151 if (devices_info[i].max_avail >= min_stripe_size) {
2152 int j;
2153 u64 alloc_size;
2154
2155 avail_space += devices_info[i].max_avail * num_stripes;
2156 alloc_size = devices_info[i].max_avail;
2157 for (j = i + 1 - num_stripes; j <= i; j++)
2158 devices_info[j].max_avail -= alloc_size;
2159 }
2160 i--;
2161 nr_devices--;
2162 }
2163
2164 kfree(devices_info);
2165 *free_bytes = avail_space;
2166 return 0;
2167 }
2168
2169 /*
2170 * Calculate numbers for 'df', pessimistic in case of mixed raid profiles.
2171 *
2172 * If there's a redundant raid level at DATA block groups, use the respective
2173 * multiplier to scale the sizes.
2174 *
2175 * Unused device space usage is based on simulating the chunk allocator
2176 * algorithm that respects the device sizes and order of allocations. This is
2177 * a close approximation of the actual use but there are other factors that may
2178 * change the result (like a new metadata chunk).
2179 *
2180 * If metadata is exhausted, f_bavail will be 0.
2181 */
btrfs_statfs(struct dentry * dentry,struct kstatfs * buf)2182 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
2183 {
2184 struct btrfs_fs_info *fs_info = btrfs_sb(dentry->d_sb);
2185 struct btrfs_super_block *disk_super = fs_info->super_copy;
2186 struct btrfs_space_info *found;
2187 u64 total_used = 0;
2188 u64 total_free_data = 0;
2189 u64 total_free_meta = 0;
2190 int bits = dentry->d_sb->s_blocksize_bits;
2191 __be32 *fsid = (__be32 *)fs_info->fs_devices->fsid;
2192 unsigned factor = 1;
2193 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
2194 int ret;
2195 u64 thresh = 0;
2196 int mixed = 0;
2197
2198 list_for_each_entry(found, &fs_info->space_info, list) {
2199 if (found->flags & BTRFS_BLOCK_GROUP_DATA) {
2200 int i;
2201
2202 total_free_data += found->disk_total - found->disk_used;
2203 total_free_data -=
2204 btrfs_account_ro_block_groups_free_space(found);
2205
2206 for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
2207 if (!list_empty(&found->block_groups[i]))
2208 factor = btrfs_bg_type_to_factor(
2209 btrfs_raid_array[i].bg_flag);
2210 }
2211 }
2212
2213 /*
2214 * Metadata in mixed block goup profiles are accounted in data
2215 */
2216 if (!mixed && found->flags & BTRFS_BLOCK_GROUP_METADATA) {
2217 if (found->flags & BTRFS_BLOCK_GROUP_DATA)
2218 mixed = 1;
2219 else
2220 total_free_meta += found->disk_total -
2221 found->disk_used;
2222 }
2223
2224 total_used += found->disk_used;
2225 }
2226
2227 buf->f_blocks = div_u64(btrfs_super_total_bytes(disk_super), factor);
2228 buf->f_blocks >>= bits;
2229 buf->f_bfree = buf->f_blocks - (div_u64(total_used, factor) >> bits);
2230
2231 /* Account global block reserve as used, it's in logical size already */
2232 spin_lock(&block_rsv->lock);
2233 /* Mixed block groups accounting is not byte-accurate, avoid overflow */
2234 if (buf->f_bfree >= block_rsv->size >> bits)
2235 buf->f_bfree -= block_rsv->size >> bits;
2236 else
2237 buf->f_bfree = 0;
2238 spin_unlock(&block_rsv->lock);
2239
2240 buf->f_bavail = div_u64(total_free_data, factor);
2241 ret = btrfs_calc_avail_data_space(fs_info, &total_free_data);
2242 if (ret)
2243 return ret;
2244 buf->f_bavail += div_u64(total_free_data, factor);
2245 buf->f_bavail = buf->f_bavail >> bits;
2246
2247 /*
2248 * We calculate the remaining metadata space minus global reserve. If
2249 * this is (supposedly) smaller than zero, there's no space. But this
2250 * does not hold in practice, the exhausted state happens where's still
2251 * some positive delta. So we apply some guesswork and compare the
2252 * delta to a 4M threshold. (Practically observed delta was ~2M.)
2253 *
2254 * We probably cannot calculate the exact threshold value because this
2255 * depends on the internal reservations requested by various
2256 * operations, so some operations that consume a few metadata will
2257 * succeed even if the Avail is zero. But this is better than the other
2258 * way around.
2259 */
2260 thresh = SZ_4M;
2261
2262 /*
2263 * We only want to claim there's no available space if we can no longer
2264 * allocate chunks for our metadata profile and our global reserve will
2265 * not fit in the free metadata space. If we aren't ->full then we
2266 * still can allocate chunks and thus are fine using the currently
2267 * calculated f_bavail.
2268 */
2269 if (!mixed && block_rsv->space_info->full &&
2270 (total_free_meta < thresh || total_free_meta - thresh < block_rsv->size))
2271 buf->f_bavail = 0;
2272
2273 buf->f_type = BTRFS_SUPER_MAGIC;
2274 buf->f_bsize = dentry->d_sb->s_blocksize;
2275 buf->f_namelen = BTRFS_NAME_LEN;
2276
2277 /* We treat it as constant endianness (it doesn't matter _which_)
2278 because we want the fsid to come out the same whether mounted
2279 on a big-endian or little-endian host */
2280 buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
2281 buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
2282 /* Mask in the root object ID too, to disambiguate subvols */
2283 buf->f_fsid.val[0] ^=
2284 BTRFS_I(d_inode(dentry))->root->root_key.objectid >> 32;
2285 buf->f_fsid.val[1] ^=
2286 BTRFS_I(d_inode(dentry))->root->root_key.objectid;
2287
2288 return 0;
2289 }
2290
btrfs_kill_super(struct super_block * sb)2291 static void btrfs_kill_super(struct super_block *sb)
2292 {
2293 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2294 kill_anon_super(sb);
2295 btrfs_free_fs_info(fs_info);
2296 }
2297
2298 static struct file_system_type btrfs_fs_type = {
2299 .owner = THIS_MODULE,
2300 .name = "btrfs",
2301 .mount = btrfs_mount,
2302 .kill_sb = btrfs_kill_super,
2303 .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA,
2304 };
2305
2306 static struct file_system_type btrfs_root_fs_type = {
2307 .owner = THIS_MODULE,
2308 .name = "btrfs",
2309 .mount = btrfs_mount_root,
2310 .kill_sb = btrfs_kill_super,
2311 .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA,
2312 };
2313
2314 MODULE_ALIAS_FS("btrfs");
2315
btrfs_control_open(struct inode * inode,struct file * file)2316 static int btrfs_control_open(struct inode *inode, struct file *file)
2317 {
2318 /*
2319 * The control file's private_data is used to hold the
2320 * transaction when it is started and is used to keep
2321 * track of whether a transaction is already in progress.
2322 */
2323 file->private_data = NULL;
2324 return 0;
2325 }
2326
2327 /*
2328 * Used by /dev/btrfs-control for devices ioctls.
2329 */
btrfs_control_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2330 static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
2331 unsigned long arg)
2332 {
2333 struct btrfs_ioctl_vol_args *vol;
2334 struct btrfs_device *device = NULL;
2335 int ret = -ENOTTY;
2336
2337 if (!capable(CAP_SYS_ADMIN))
2338 return -EPERM;
2339
2340 vol = memdup_user((void __user *)arg, sizeof(*vol));
2341 if (IS_ERR(vol))
2342 return PTR_ERR(vol);
2343 vol->name[BTRFS_PATH_NAME_MAX] = '\0';
2344
2345 switch (cmd) {
2346 case BTRFS_IOC_SCAN_DEV:
2347 mutex_lock(&uuid_mutex);
2348 device = btrfs_scan_one_device(vol->name, FMODE_READ,
2349 &btrfs_root_fs_type);
2350 ret = PTR_ERR_OR_ZERO(device);
2351 mutex_unlock(&uuid_mutex);
2352 break;
2353 case BTRFS_IOC_FORGET_DEV:
2354 ret = btrfs_forget_devices(vol->name);
2355 break;
2356 case BTRFS_IOC_DEVICES_READY:
2357 mutex_lock(&uuid_mutex);
2358 device = btrfs_scan_one_device(vol->name, FMODE_READ,
2359 &btrfs_root_fs_type);
2360 if (IS_ERR(device)) {
2361 mutex_unlock(&uuid_mutex);
2362 ret = PTR_ERR(device);
2363 break;
2364 }
2365 ret = !(device->fs_devices->num_devices ==
2366 device->fs_devices->total_devices);
2367 mutex_unlock(&uuid_mutex);
2368 break;
2369 case BTRFS_IOC_GET_SUPPORTED_FEATURES:
2370 ret = btrfs_ioctl_get_supported_features((void __user*)arg);
2371 break;
2372 }
2373
2374 kfree(vol);
2375 return ret;
2376 }
2377
btrfs_freeze(struct super_block * sb)2378 static int btrfs_freeze(struct super_block *sb)
2379 {
2380 struct btrfs_trans_handle *trans;
2381 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2382 struct btrfs_root *root = fs_info->tree_root;
2383
2384 set_bit(BTRFS_FS_FROZEN, &fs_info->flags);
2385 /*
2386 * We don't need a barrier here, we'll wait for any transaction that
2387 * could be in progress on other threads (and do delayed iputs that
2388 * we want to avoid on a frozen filesystem), or do the commit
2389 * ourselves.
2390 */
2391 trans = btrfs_attach_transaction_barrier(root);
2392 if (IS_ERR(trans)) {
2393 /* no transaction, don't bother */
2394 if (PTR_ERR(trans) == -ENOENT)
2395 return 0;
2396 return PTR_ERR(trans);
2397 }
2398 return btrfs_commit_transaction(trans);
2399 }
2400
btrfs_unfreeze(struct super_block * sb)2401 static int btrfs_unfreeze(struct super_block *sb)
2402 {
2403 struct btrfs_fs_info *fs_info = btrfs_sb(sb);
2404
2405 clear_bit(BTRFS_FS_FROZEN, &fs_info->flags);
2406 return 0;
2407 }
2408
btrfs_show_devname(struct seq_file * m,struct dentry * root)2409 static int btrfs_show_devname(struct seq_file *m, struct dentry *root)
2410 {
2411 struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb);
2412 struct btrfs_device *dev, *first_dev = NULL;
2413
2414 /*
2415 * Lightweight locking of the devices. We should not need
2416 * device_list_mutex here as we only read the device data and the list
2417 * is protected by RCU. Even if a device is deleted during the list
2418 * traversals, we'll get valid data, the freeing callback will wait at
2419 * least until the rcu_read_unlock.
2420 */
2421 rcu_read_lock();
2422 list_for_each_entry_rcu(dev, &fs_info->fs_devices->devices, dev_list) {
2423 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state))
2424 continue;
2425 if (!dev->name)
2426 continue;
2427 if (!first_dev || dev->devid < first_dev->devid)
2428 first_dev = dev;
2429 }
2430
2431 if (first_dev)
2432 seq_escape(m, rcu_str_deref(first_dev->name), " \t\n\\");
2433 else
2434 WARN_ON(1);
2435 rcu_read_unlock();
2436 return 0;
2437 }
2438
2439 static const struct super_operations btrfs_super_ops = {
2440 .drop_inode = btrfs_drop_inode,
2441 .evict_inode = btrfs_evict_inode,
2442 .put_super = btrfs_put_super,
2443 .sync_fs = btrfs_sync_fs,
2444 .show_options = btrfs_show_options,
2445 .show_devname = btrfs_show_devname,
2446 .alloc_inode = btrfs_alloc_inode,
2447 .destroy_inode = btrfs_destroy_inode,
2448 .free_inode = btrfs_free_inode,
2449 .statfs = btrfs_statfs,
2450 .remount_fs = btrfs_remount,
2451 .freeze_fs = btrfs_freeze,
2452 .unfreeze_fs = btrfs_unfreeze,
2453 };
2454
2455 static const struct file_operations btrfs_ctl_fops = {
2456 .open = btrfs_control_open,
2457 .unlocked_ioctl = btrfs_control_ioctl,
2458 .compat_ioctl = compat_ptr_ioctl,
2459 .owner = THIS_MODULE,
2460 .llseek = noop_llseek,
2461 };
2462
2463 static struct miscdevice btrfs_misc = {
2464 .minor = BTRFS_MINOR,
2465 .name = "btrfs-control",
2466 .fops = &btrfs_ctl_fops
2467 };
2468
2469 MODULE_ALIAS_MISCDEV(BTRFS_MINOR);
2470 MODULE_ALIAS("devname:btrfs-control");
2471
btrfs_interface_init(void)2472 static int __init btrfs_interface_init(void)
2473 {
2474 return misc_register(&btrfs_misc);
2475 }
2476
btrfs_interface_exit(void)2477 static __cold void btrfs_interface_exit(void)
2478 {
2479 misc_deregister(&btrfs_misc);
2480 }
2481
btrfs_print_mod_info(void)2482 static void __init btrfs_print_mod_info(void)
2483 {
2484 static const char options[] = ""
2485 #ifdef CONFIG_BTRFS_DEBUG
2486 ", debug=on"
2487 #endif
2488 #ifdef CONFIG_BTRFS_ASSERT
2489 ", assert=on"
2490 #endif
2491 #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY
2492 ", integrity-checker=on"
2493 #endif
2494 #ifdef CONFIG_BTRFS_FS_REF_VERIFY
2495 ", ref-verify=on"
2496 #endif
2497 ;
2498 pr_info("Btrfs loaded, crc32c=%s%s\n", crc32c_impl(), options);
2499 }
2500
init_btrfs_fs(void)2501 static int __init init_btrfs_fs(void)
2502 {
2503 int err;
2504
2505 btrfs_props_init();
2506
2507 err = btrfs_init_sysfs();
2508 if (err)
2509 return err;
2510
2511 btrfs_init_compress();
2512
2513 err = btrfs_init_cachep();
2514 if (err)
2515 goto free_compress;
2516
2517 err = extent_io_init();
2518 if (err)
2519 goto free_cachep;
2520
2521 err = extent_state_cache_init();
2522 if (err)
2523 goto free_extent_io;
2524
2525 err = extent_map_init();
2526 if (err)
2527 goto free_extent_state_cache;
2528
2529 err = ordered_data_init();
2530 if (err)
2531 goto free_extent_map;
2532
2533 err = btrfs_delayed_inode_init();
2534 if (err)
2535 goto free_ordered_data;
2536
2537 err = btrfs_auto_defrag_init();
2538 if (err)
2539 goto free_delayed_inode;
2540
2541 err = btrfs_delayed_ref_init();
2542 if (err)
2543 goto free_auto_defrag;
2544
2545 err = btrfs_prelim_ref_init();
2546 if (err)
2547 goto free_delayed_ref;
2548
2549 err = btrfs_end_io_wq_init();
2550 if (err)
2551 goto free_prelim_ref;
2552
2553 err = btrfs_interface_init();
2554 if (err)
2555 goto free_end_io_wq;
2556
2557 btrfs_init_lockdep();
2558
2559 btrfs_print_mod_info();
2560
2561 err = btrfs_run_sanity_tests();
2562 if (err)
2563 goto unregister_ioctl;
2564
2565 err = register_filesystem(&btrfs_fs_type);
2566 if (err)
2567 goto unregister_ioctl;
2568
2569 return 0;
2570
2571 unregister_ioctl:
2572 btrfs_interface_exit();
2573 free_end_io_wq:
2574 btrfs_end_io_wq_exit();
2575 free_prelim_ref:
2576 btrfs_prelim_ref_exit();
2577 free_delayed_ref:
2578 btrfs_delayed_ref_exit();
2579 free_auto_defrag:
2580 btrfs_auto_defrag_exit();
2581 free_delayed_inode:
2582 btrfs_delayed_inode_exit();
2583 free_ordered_data:
2584 ordered_data_exit();
2585 free_extent_map:
2586 extent_map_exit();
2587 free_extent_state_cache:
2588 extent_state_cache_exit();
2589 free_extent_io:
2590 extent_io_exit();
2591 free_cachep:
2592 btrfs_destroy_cachep();
2593 free_compress:
2594 btrfs_exit_compress();
2595 btrfs_exit_sysfs();
2596
2597 return err;
2598 }
2599
exit_btrfs_fs(void)2600 static void __exit exit_btrfs_fs(void)
2601 {
2602 btrfs_destroy_cachep();
2603 btrfs_delayed_ref_exit();
2604 btrfs_auto_defrag_exit();
2605 btrfs_delayed_inode_exit();
2606 btrfs_prelim_ref_exit();
2607 ordered_data_exit();
2608 extent_map_exit();
2609 extent_state_cache_exit();
2610 extent_io_exit();
2611 btrfs_interface_exit();
2612 btrfs_end_io_wq_exit();
2613 unregister_filesystem(&btrfs_fs_type);
2614 btrfs_exit_sysfs();
2615 btrfs_cleanup_fs_uuids();
2616 btrfs_exit_compress();
2617 }
2618
2619 late_initcall(init_btrfs_fs);
2620 module_exit(exit_btrfs_fs)
2621
2622 MODULE_LICENSE("GPL");
2623 MODULE_IMPORT_NS(ANDROID_GKI_VFS_EXPORT_ONLY);
2624 MODULE_SOFTDEP("pre: crc32c");
2625 MODULE_SOFTDEP("pre: xxhash64");
2626 MODULE_SOFTDEP("pre: sha256");
2627 MODULE_SOFTDEP("pre: blake2b-256");
2628