?  search:
summary | log | graphiclog1 | graphiclog2 | commit | commitdiff | tree | refs | edit | fork
blame | history | raw | HEAD
Linux 4.19.133
[linux/fpc-iii.git] / fs / btrfs / scrub.c
blobfee8995c9a0c4fe2b3b5440cd77d008c07490df2
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2011, 2012 STRATO. All rights reserved.
4 */
5
6 #include <linux/blkdev.h>
7 #include <linux/ratelimit.h>
8 #include <linux/sched/mm.h>
9 #include "ctree.h"
10 #include "volumes.h"
11 #include "disk-io.h"
12 #include "ordered-data.h"
13 #include "transaction.h"
14 #include "backref.h"
15 #include "extent_io.h"
16 #include "dev-replace.h"
17 #include "check-integrity.h"
18 #include "rcu-string.h"
19 #include "raid56.h"
20
21 /*
22 * This is only the first step towards a full-features scrub. It reads all
23 * extent and super block and verifies the checksums. In case a bad checksum
24 * is found or the extent cannot be read, good data will be written back if
25 * any can be found.
26 *
27 * Future enhancements:
28 * - In case an unrepairable extent is encountered, track which files are
29 * affected and report them
30 * - track and record media errors, throw out bad devices
31 * - add a mode to also read unallocated space
32 */
33
34 struct scrub_block;
35 struct scrub_ctx;
36
37 /*
38 * the following three values only influence the performance.
39 * The last one configures the number of parallel and outstanding I/O
40 * operations. The first two values configure an upper limit for the number
41 * of (dynamically allocated) pages that are added to a bio.
42 */
43 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */
44 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */
45 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */
46
47 /*
48 * the following value times PAGE_SIZE needs to be large enough to match the
49 * largest node/leaf/sector size that shall be supported.
50 * Values larger than BTRFS_STRIPE_LEN are not supported.
51 */
52 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
53
54 struct scrub_recover {
55 refcount_t refs;
56 struct btrfs_bio *bbio;
57 u64 map_length;
58 };
59
60 struct scrub_page {
61 struct scrub_block *sblock;
62 struct page *page;
63 struct btrfs_device *dev;
64 struct list_head list;
65 u64 flags; /* extent flags */
66 u64 generation;
67 u64 logical;
68 u64 physical;
69 u64 physical_for_dev_replace;
70 atomic_t refs;
71 struct {
72 unsigned int mirror_num:8;
73 unsigned int have_csum:1;
74 unsigned int io_error:1;
75 };
76 u8 csum[BTRFS_CSUM_SIZE];
77
78 struct scrub_recover *recover;
79 };
80
81 struct scrub_bio {
82 int index;
83 struct scrub_ctx *sctx;
84 struct btrfs_device *dev;
85 struct bio *bio;
86 blk_status_t status;
87 u64 logical;
88 u64 physical;
89 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO
90 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO];
91 #else
92 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO];
93 #endif
94 int page_count;
95 int next_free;
96 struct btrfs_work work;
97 };
98
99 struct scrub_block {
100 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK];
101 int page_count;
102 atomic_t outstanding_pages;
103 refcount_t refs; /* free mem on transition to zero */
104 struct scrub_ctx *sctx;
105 struct scrub_parity *sparity;
106 struct {
107 unsigned int header_error:1;
108 unsigned int checksum_error:1;
109 unsigned int no_io_error_seen:1;
110 unsigned int generation_error:1; /* also sets header_error */
111
112 /* The following is for the data used to check parity */
113 /* It is for the data with checksum */
114 unsigned int data_corrected:1;
115 };
116 struct btrfs_work work;
117 };
118
119 /* Used for the chunks with parity stripe such RAID5/6 */
120 struct scrub_parity {
121 struct scrub_ctx *sctx;
122
123 struct btrfs_device *scrub_dev;
124
125 u64 logic_start;
126
127 u64 logic_end;
128
129 int nsectors;
130
131 u64 stripe_len;
132
133 refcount_t refs;
134
135 struct list_head spages;
136
137 /* Work of parity check and repair */
138 struct btrfs_work work;
139
140 /* Mark the parity blocks which have data */
141 unsigned long *dbitmap;
142
143 /*
144 * Mark the parity blocks which have data, but errors happen when
145 * read data or check data
146 */
147 unsigned long *ebitmap;
148
149 unsigned long bitmap[0];
150 };
151
152 struct scrub_ctx {
153 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX];
154 struct btrfs_fs_info *fs_info;
155 int first_free;
156 int curr;
157 atomic_t bios_in_flight;
158 atomic_t workers_pending;
159 spinlock_t list_lock;
160 wait_queue_head_t list_wait;
161 u16 csum_size;
162 struct list_head csum_list;
163 atomic_t cancel_req;
164 int readonly;
165 int pages_per_rd_bio;
166
167 int is_dev_replace;
168
169 struct scrub_bio *wr_curr_bio;
170 struct mutex wr_lock;
171 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
172 struct btrfs_device *wr_tgtdev;
173 bool flush_all_writes;
174
175 /*
176 * statistics
177 */
178 struct btrfs_scrub_progress stat;
179 spinlock_t stat_lock;
180
181 /*
182 * Use a ref counter to avoid use-after-free issues. Scrub workers
183 * decrement bios_in_flight and workers_pending and then do a wakeup
184 * on the list_wait wait queue. We must ensure the main scrub task
185 * doesn't free the scrub context before or while the workers are
186 * doing the wakeup() call.
187 */
188 refcount_t refs;
189 };
190
191 struct scrub_warning {
192 struct btrfs_path *path;
193 u64 extent_item_size;
194 const char *errstr;
195 u64 physical;
196 u64 logical;
197 struct btrfs_device *dev;
198 };
199
200 struct full_stripe_lock {
201 struct rb_node node;
202 u64 logical;
203 u64 refs;
204 struct mutex mutex;
205 };
206
207 static void scrub_pending_bio_inc(struct scrub_ctx *sctx);
208 static void scrub_pending_bio_dec(struct scrub_ctx *sctx);
209 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
210 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
211 struct scrub_block *sblocks_for_recheck);
212 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
213 struct scrub_block *sblock,
214 int retry_failed_mirror);
215 static void scrub_recheck_block_checksum(struct scrub_block *sblock);
216 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
217 struct scrub_block *sblock_good);
218 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
219 struct scrub_block *sblock_good,
220 int page_num, int force_write);
221 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock);
222 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
223 int page_num);
224 static int scrub_checksum_data(struct scrub_block *sblock);
225 static int scrub_checksum_tree_block(struct scrub_block *sblock);
226 static int scrub_checksum_super(struct scrub_block *sblock);
227 static void scrub_block_get(struct scrub_block *sblock);
228 static void scrub_block_put(struct scrub_block *sblock);
229 static void scrub_page_get(struct scrub_page *spage);
230 static void scrub_page_put(struct scrub_page *spage);
231 static void scrub_parity_get(struct scrub_parity *sparity);
232 static void scrub_parity_put(struct scrub_parity *sparity);
233 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
234 struct scrub_page *spage);
235 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
236 u64 physical, struct btrfs_device *dev, u64 flags,
237 u64 gen, int mirror_num, u8 *csum, int force,
238 u64 physical_for_dev_replace);
239 static void scrub_bio_end_io(struct bio *bio);
240 static void scrub_bio_end_io_worker(struct btrfs_work *work);
241 static void scrub_block_complete(struct scrub_block *sblock);
242 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
243 u64 extent_logical, u64 extent_len,
244 u64 *extent_physical,
245 struct btrfs_device **extent_dev,
246 int *extent_mirror_num);
247 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
248 struct scrub_page *spage);
249 static void scrub_wr_submit(struct scrub_ctx *sctx);
250 static void scrub_wr_bio_end_io(struct bio *bio);
251 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work);
252 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
253 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
254 static void scrub_put_ctx(struct scrub_ctx *sctx);
255
256 static inline int scrub_is_page_on_raid56(struct scrub_page *page)
257 {
258 return page->recover &&
259 (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
260 }
261
262 static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
263 {
264 refcount_inc(&sctx->refs);
265 atomic_inc(&sctx->bios_in_flight);
266 }
267
268 static void scrub_pending_bio_dec(struct scrub_ctx *sctx)
269 {
270 atomic_dec(&sctx->bios_in_flight);
271 wake_up(&sctx->list_wait);
272 scrub_put_ctx(sctx);
273 }
274
275 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
276 {
277 while (atomic_read(&fs_info->scrub_pause_req)) {
278 mutex_unlock(&fs_info->scrub_lock);
279 wait_event(fs_info->scrub_pause_wait,
280 atomic_read(&fs_info->scrub_pause_req) == 0);
281 mutex_lock(&fs_info->scrub_lock);
282 }
283 }
284
285 static void scrub_pause_on(struct btrfs_fs_info *fs_info)
286 {
287 atomic_inc(&fs_info->scrubs_paused);
288 wake_up(&fs_info->scrub_pause_wait);
289 }
290
291 static void scrub_pause_off(struct btrfs_fs_info *fs_info)
292 {
293 mutex_lock(&fs_info->scrub_lock);
294 __scrub_blocked_if_needed(fs_info);
295 atomic_dec(&fs_info->scrubs_paused);
296 mutex_unlock(&fs_info->scrub_lock);
297
298 wake_up(&fs_info->scrub_pause_wait);
299 }
300
301 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
302 {
303 scrub_pause_on(fs_info);
304 scrub_pause_off(fs_info);
305 }
306
307 /*
308 * Insert new full stripe lock into full stripe locks tree
309 *
310 * Return pointer to existing or newly inserted full_stripe_lock structure if
311 * everything works well.
312 * Return ERR_PTR(-ENOMEM) if we failed to allocate memory
313 *
314 * NOTE: caller must hold full_stripe_locks_root->lock before calling this
315 * function
316 */
317 static struct full_stripe_lock *insert_full_stripe_lock(
318 struct btrfs_full_stripe_locks_tree *locks_root,
319 u64 fstripe_logical)
320 {
321 struct rb_node **p;
322 struct rb_node *parent = NULL;
323 struct full_stripe_lock *entry;
324 struct full_stripe_lock *ret;
325 unsigned int nofs_flag;
326
327 lockdep_assert_held(&locks_root->lock);
328
329 p = &locks_root->root.rb_node;
330 while (*p) {
331 parent = *p;
332 entry = rb_entry(parent, struct full_stripe_lock, node);
333 if (fstripe_logical < entry->logical) {
334 p = &(*p)->rb_left;
335 } else if (fstripe_logical > entry->logical) {
336 p = &(*p)->rb_right;
337 } else {
338 entry->refs++;
339 return entry;
340 }
341 }
342
343 /*
344 * Insert new lock.
345 *
346 * We must use GFP_NOFS because the scrub task might be waiting for a
347 * worker task executing this function and in turn a transaction commit
348 * might be waiting the scrub task to pause (which needs to wait for all
349 * the worker tasks to complete before pausing).
350 */
351 nofs_flag = memalloc_nofs_save();
352 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
353 memalloc_nofs_restore(nofs_flag);
354 if (!ret)
355 return ERR_PTR(-ENOMEM);
356 ret->logical = fstripe_logical;
357 ret->refs = 1;
358 mutex_init(&ret->mutex);
359
360 rb_link_node(&ret->node, parent, p);
361 rb_insert_color(&ret->node, &locks_root->root);
362 return ret;
363 }
364
365 /*
366 * Search for a full stripe lock of a block group
367 *
368 * Return pointer to existing full stripe lock if found
369 * Return NULL if not found
370 */
371 static struct full_stripe_lock *search_full_stripe_lock(
372 struct btrfs_full_stripe_locks_tree *locks_root,
373 u64 fstripe_logical)
374 {
375 struct rb_node *node;
376 struct full_stripe_lock *entry;
377
378 lockdep_assert_held(&locks_root->lock);
379
380 node = locks_root->root.rb_node;
381 while (node) {
382 entry = rb_entry(node, struct full_stripe_lock, node);
383 if (fstripe_logical < entry->logical)
384 node = node->rb_left;
385 else if (fstripe_logical > entry->logical)
386 node = node->rb_right;
387 else
388 return entry;
389 }
390 return NULL;
391 }
392
393 /*
394 * Helper to get full stripe logical from a normal bytenr.
395 *
396 * Caller must ensure @cache is a RAID56 block group.
397 */
398 static u64 get_full_stripe_logical(struct btrfs_block_group_cache *cache,
399 u64 bytenr)
400 {
401 u64 ret;
402
403 /*
404 * Due to chunk item size limit, full stripe length should not be
405 * larger than U32_MAX. Just a sanity check here.
406 */
407 WARN_ON_ONCE(cache->full_stripe_len >= U32_MAX);
408
409 /*
410 * round_down() can only handle power of 2, while RAID56 full
411 * stripe length can be 64KiB * n, so we need to manually round down.
412 */
413 ret = div64_u64(bytenr - cache->key.objectid, cache->full_stripe_len) *
414 cache->full_stripe_len + cache->key.objectid;
415 return ret;
416 }
417
418 /*
419 * Lock a full stripe to avoid concurrency of recovery and read
420 *
421 * It's only used for profiles with parities (RAID5/6), for other profiles it
422 * does nothing.
423 *
424 * Return 0 if we locked full stripe covering @bytenr, with a mutex held.
425 * So caller must call unlock_full_stripe() at the same context.
426 *
427 * Return <0 if encounters error.
428 */
429 static int lock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
430 bool *locked_ret)
431 {
432 struct btrfs_block_group_cache *bg_cache;
433 struct btrfs_full_stripe_locks_tree *locks_root;
434 struct full_stripe_lock *existing;
435 u64 fstripe_start;
436 int ret = 0;
437
438 *locked_ret = false;
439 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
440 if (!bg_cache) {
441 ASSERT(0);
442 return -ENOENT;
443 }
444
445 /* Profiles not based on parity don't need full stripe lock */
446 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
447 goto out;
448 locks_root = &bg_cache->full_stripe_locks_root;
449
450 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
451
452 /* Now insert the full stripe lock */
453 mutex_lock(&locks_root->lock);
454 existing = insert_full_stripe_lock(locks_root, fstripe_start);
455 mutex_unlock(&locks_root->lock);
456 if (IS_ERR(existing)) {
457 ret = PTR_ERR(existing);
458 goto out;
459 }
460 mutex_lock(&existing->mutex);
461 *locked_ret = true;
462 out:
463 btrfs_put_block_group(bg_cache);
464 return ret;
465 }
466
467 /*
468 * Unlock a full stripe.
469 *
470 * NOTE: Caller must ensure it's the same context calling corresponding
471 * lock_full_stripe().
472 *
473 * Return 0 if we unlock full stripe without problem.
474 * Return <0 for error
475 */
476 static int unlock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
477 bool locked)
478 {
479 struct btrfs_block_group_cache *bg_cache;
480 struct btrfs_full_stripe_locks_tree *locks_root;
481 struct full_stripe_lock *fstripe_lock;
482 u64 fstripe_start;
483 bool freeit = false;
484 int ret = 0;
485
486 /* If we didn't acquire full stripe lock, no need to continue */
487 if (!locked)
488 return 0;
489
490 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
491 if (!bg_cache) {
492 ASSERT(0);
493 return -ENOENT;
494 }
495 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
496 goto out;
497
498 locks_root = &bg_cache->full_stripe_locks_root;
499 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
500
501 mutex_lock(&locks_root->lock);
502 fstripe_lock = search_full_stripe_lock(locks_root, fstripe_start);
503 /* Unpaired unlock_full_stripe() detected */
504 if (!fstripe_lock) {
505 WARN_ON(1);
506 ret = -ENOENT;
507 mutex_unlock(&locks_root->lock);
508 goto out;
509 }
510
511 if (fstripe_lock->refs == 0) {
512 WARN_ON(1);
513 btrfs_warn(fs_info, "full stripe lock at %llu refcount underflow",
514 fstripe_lock->logical);
515 } else {
516 fstripe_lock->refs--;
517 }
518
519 if (fstripe_lock->refs == 0) {
520 rb_erase(&fstripe_lock->node, &locks_root->root);
521 freeit = true;
522 }
523 mutex_unlock(&locks_root->lock);
524
525 mutex_unlock(&fstripe_lock->mutex);
526 if (freeit)
527 kfree(fstripe_lock);
528 out:
529 btrfs_put_block_group(bg_cache);
530 return ret;
531 }
532
533 static void scrub_free_csums(struct scrub_ctx *sctx)
534 {
535 while (!list_empty(&sctx->csum_list)) {
536 struct btrfs_ordered_sum *sum;
537 sum = list_first_entry(&sctx->csum_list,
538 struct btrfs_ordered_sum, list);
539 list_del(&sum->list);
540 kfree(sum);
541 }
542 }
543
544 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
545 {
546 int i;
547
548 if (!sctx)
549 return;
550
551 /* this can happen when scrub is cancelled */
552 if (sctx->curr != -1) {
553 struct scrub_bio *sbio = sctx->bios[sctx->curr];
554
555 for (i = 0; i < sbio->page_count; i++) {
556 WARN_ON(!sbio->pagev[i]->page);
557 scrub_block_put(sbio->pagev[i]->sblock);
558 }
559 bio_put(sbio->bio);
560 }
561
562 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
563 struct scrub_bio *sbio = sctx->bios[i];
564
565 if (!sbio)
566 break;
567 kfree(sbio);
568 }
569
570 kfree(sctx->wr_curr_bio);
571 scrub_free_csums(sctx);
572 kfree(sctx);
573 }
574
575 static void scrub_put_ctx(struct scrub_ctx *sctx)
576 {
577 if (refcount_dec_and_test(&sctx->refs))
578 scrub_free_ctx(sctx);
579 }
580
581 static noinline_for_stack struct scrub_ctx *scrub_setup_ctx(
582 struct btrfs_fs_info *fs_info, int is_dev_replace)
583 {
584 struct scrub_ctx *sctx;
585 int i;
586
587 sctx = kzalloc(sizeof(*sctx), GFP_KERNEL);
588 if (!sctx)
589 goto nomem;
590 refcount_set(&sctx->refs, 1);
591 sctx->is_dev_replace = is_dev_replace;
592 sctx->pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
593 sctx->curr = -1;
594 sctx->fs_info = fs_info;
595 INIT_LIST_HEAD(&sctx->csum_list);
596 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
597 struct scrub_bio *sbio;
598
599 sbio = kzalloc(sizeof(*sbio), GFP_KERNEL);
600 if (!sbio)
601 goto nomem;
602 sctx->bios[i] = sbio;
603
604 sbio->index = i;
605 sbio->sctx = sctx;
606 sbio->page_count = 0;
607 btrfs_init_work(&sbio->work, btrfs_scrub_helper,
608 scrub_bio_end_io_worker, NULL, NULL);
609
610 if (i != SCRUB_BIOS_PER_SCTX - 1)
611 sctx->bios[i]->next_free = i + 1;
612 else
613 sctx->bios[i]->next_free = -1;
614 }
615 sctx->first_free = 0;
616 atomic_set(&sctx->bios_in_flight, 0);
617 atomic_set(&sctx->workers_pending, 0);
618 atomic_set(&sctx->cancel_req, 0);
619 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
620
621 spin_lock_init(&sctx->list_lock);
622 spin_lock_init(&sctx->stat_lock);
623 init_waitqueue_head(&sctx->list_wait);
624
625 WARN_ON(sctx->wr_curr_bio != NULL);
626 mutex_init(&sctx->wr_lock);
627 sctx->wr_curr_bio = NULL;
628 if (is_dev_replace) {
629 WARN_ON(!fs_info->dev_replace.tgtdev);
630 sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
631 sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
632 sctx->flush_all_writes = false;
633 }
634
635 return sctx;
636
637 nomem:
638 scrub_free_ctx(sctx);
639 return ERR_PTR(-ENOMEM);
640 }
641
642 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root,
643 void *warn_ctx)
644 {
645 u64 isize;
646 u32 nlink;
647 int ret;
648 int i;
649 unsigned nofs_flag;
650 struct extent_buffer *eb;
651 struct btrfs_inode_item *inode_item;
652 struct scrub_warning *swarn = warn_ctx;
653 struct btrfs_fs_info *fs_info = swarn->dev->fs_info;
654 struct inode_fs_paths *ipath = NULL;
655 struct btrfs_root *local_root;
656 struct btrfs_key root_key;
657 struct btrfs_key key;
658
659 root_key.objectid = root;
660 root_key.type = BTRFS_ROOT_ITEM_KEY;
661 root_key.offset = (u64)-1;
662 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
663 if (IS_ERR(local_root)) {
664 ret = PTR_ERR(local_root);
665 goto err;
666 }
667
668 /*
669 * this makes the path point to (inum INODE_ITEM ioff)
670 */
671 key.objectid = inum;
672 key.type = BTRFS_INODE_ITEM_KEY;
673 key.offset = 0;
674
675 ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0);
676 if (ret) {
677 btrfs_release_path(swarn->path);
678 goto err;
679 }
680
681 eb = swarn->path->nodes[0];
682 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
683 struct btrfs_inode_item);
684 isize = btrfs_inode_size(eb, inode_item);
685 nlink = btrfs_inode_nlink(eb, inode_item);
686 btrfs_release_path(swarn->path);
687
688 /*
689 * init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub
690 * uses GFP_NOFS in this context, so we keep it consistent but it does
691 * not seem to be strictly necessary.
692 */
693 nofs_flag = memalloc_nofs_save();
694 ipath = init_ipath(4096, local_root, swarn->path);
695 memalloc_nofs_restore(nofs_flag);
696 if (IS_ERR(ipath)) {
697 ret = PTR_ERR(ipath);
698 ipath = NULL;
699 goto err;
700 }
701 ret = paths_from_inode(inum, ipath);
702
703 if (ret < 0)
704 goto err;
705
706 /*
707 * we deliberately ignore the bit ipath might have been too small to
708 * hold all of the paths here
709 */
710 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
711 btrfs_warn_in_rcu(fs_info,
712 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %llu, links %u (path: %s)",
713 swarn->errstr, swarn->logical,
714 rcu_str_deref(swarn->dev->name),
715 swarn->physical,
716 root, inum, offset,
717 min(isize - offset, (u64)PAGE_SIZE), nlink,
718 (char *)(unsigned long)ipath->fspath->val[i]);
719
720 free_ipath(ipath);
721 return 0;
722
723 err:
724 btrfs_warn_in_rcu(fs_info,
725 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d",
726 swarn->errstr, swarn->logical,
727 rcu_str_deref(swarn->dev->name),
728 swarn->physical,
729 root, inum, offset, ret);
730
731 free_ipath(ipath);
732 return 0;
733 }
734
735 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
736 {
737 struct btrfs_device *dev;
738 struct btrfs_fs_info *fs_info;
739 struct btrfs_path *path;
740 struct btrfs_key found_key;
741 struct extent_buffer *eb;
742 struct btrfs_extent_item *ei;
743 struct scrub_warning swarn;
744 unsigned long ptr = 0;
745 u64 extent_item_pos;
746 u64 flags = 0;
747 u64 ref_root;
748 u32 item_size;
749 u8 ref_level = 0;
750 int ret;
751
752 WARN_ON(sblock->page_count < 1);
753 dev = sblock->pagev[0]->dev;
754 fs_info = sblock->sctx->fs_info;
755
756 path = btrfs_alloc_path();
757 if (!path)
758 return;
759
760 swarn.physical = sblock->pagev[0]->physical;
761 swarn.logical = sblock->pagev[0]->logical;
762 swarn.errstr = errstr;
763 swarn.dev = NULL;
764
765 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
766 &flags);
767 if (ret < 0)
768 goto out;
769
770 extent_item_pos = swarn.logical - found_key.objectid;
771 swarn.extent_item_size = found_key.offset;
772
773 eb = path->nodes[0];
774 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
775 item_size = btrfs_item_size_nr(eb, path->slots[0]);
776
777 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
778 do {
779 ret = tree_backref_for_extent(&ptr, eb, &found_key, ei,
780 item_size, &ref_root,
781 &ref_level);
782 btrfs_warn_in_rcu(fs_info,
783 "%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu",
784 errstr, swarn.logical,
785 rcu_str_deref(dev->name),
786 swarn.physical,
787 ref_level ? "node" : "leaf",
788 ret < 0 ? -1 : ref_level,
789 ret < 0 ? -1 : ref_root);
790 } while (ret != 1);
791 btrfs_release_path(path);
792 } else {
793 btrfs_release_path(path);
794 swarn.path = path;
795 swarn.dev = dev;
796 iterate_extent_inodes(fs_info, found_key.objectid,
797 extent_item_pos, 1,
798 scrub_print_warning_inode, &swarn, false);
799 }
800
801 out:
802 btrfs_free_path(path);
803 }
804
805 static inline void scrub_get_recover(struct scrub_recover *recover)
806 {
807 refcount_inc(&recover->refs);
808 }
809
810 static inline void scrub_put_recover(struct btrfs_fs_info *fs_info,
811 struct scrub_recover *recover)
812 {
813 if (refcount_dec_and_test(&recover->refs)) {
814 btrfs_bio_counter_dec(fs_info);
815 btrfs_put_bbio(recover->bbio);
816 kfree(recover);
817 }
818 }
819
820 /*
821 * scrub_handle_errored_block gets called when either verification of the
822 * pages failed or the bio failed to read, e.g. with EIO. In the latter
823 * case, this function handles all pages in the bio, even though only one
824 * may be bad.
825 * The goal of this function is to repair the errored block by using the
826 * contents of one of the mirrors.
827 */
828 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
829 {
830 struct scrub_ctx *sctx = sblock_to_check->sctx;
831 struct btrfs_device *dev;
832 struct btrfs_fs_info *fs_info;
833 u64 logical;
834 unsigned int failed_mirror_index;
835 unsigned int is_metadata;
836 unsigned int have_csum;
837 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
838 struct scrub_block *sblock_bad;
839 int ret;
840 int mirror_index;
841 int page_num;
842 int success;
843 bool full_stripe_locked;
844 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
845 DEFAULT_RATELIMIT_BURST);
846
847 BUG_ON(sblock_to_check->page_count < 1);
848 fs_info = sctx->fs_info;
849 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) {
850 /*
851 * if we find an error in a super block, we just report it.
852 * They will get written with the next transaction commit
853 * anyway
854 */
855 spin_lock(&sctx->stat_lock);
856 ++sctx->stat.super_errors;
857 spin_unlock(&sctx->stat_lock);
858 return 0;
859 }
860 logical = sblock_to_check->pagev[0]->logical;
861 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1);
862 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1;
863 is_metadata = !(sblock_to_check->pagev[0]->flags &
864 BTRFS_EXTENT_FLAG_DATA);
865 have_csum = sblock_to_check->pagev[0]->have_csum;
866 dev = sblock_to_check->pagev[0]->dev;
867
868 /*
869 * For RAID5/6, race can happen for a different device scrub thread.
870 * For data corruption, Parity and Data threads will both try
871 * to recovery the data.
872 * Race can lead to doubly added csum error, or even unrecoverable
873 * error.
874 */
875 ret = lock_full_stripe(fs_info, logical, &full_stripe_locked);
876 if (ret < 0) {
877 spin_lock(&sctx->stat_lock);
878 if (ret == -ENOMEM)
879 sctx->stat.malloc_errors++;
880 sctx->stat.read_errors++;
881 sctx->stat.uncorrectable_errors++;
882 spin_unlock(&sctx->stat_lock);
883 return ret;
884 }
885
886 /*
887 * read all mirrors one after the other. This includes to
888 * re-read the extent or metadata block that failed (that was
889 * the cause that this fixup code is called) another time,
890 * page by page this time in order to know which pages
891 * caused I/O errors and which ones are good (for all mirrors).
892 * It is the goal to handle the situation when more than one
893 * mirror contains I/O errors, but the errors do not
894 * overlap, i.e. the data can be repaired by selecting the
895 * pages from those mirrors without I/O error on the
896 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
897 * would be that mirror #1 has an I/O error on the first page,
898 * the second page is good, and mirror #2 has an I/O error on
899 * the second page, but the first page is good.
900 * Then the first page of the first mirror can be repaired by
901 * taking the first page of the second mirror, and the
902 * second page of the second mirror can be repaired by
903 * copying the contents of the 2nd page of the 1st mirror.
904 * One more note: if the pages of one mirror contain I/O
905 * errors, the checksum cannot be verified. In order to get
906 * the best data for repairing, the first attempt is to find
907 * a mirror without I/O errors and with a validated checksum.
908 * Only if this is not possible, the pages are picked from
909 * mirrors with I/O errors without considering the checksum.
910 * If the latter is the case, at the end, the checksum of the
911 * repaired area is verified in order to correctly maintain
912 * the statistics.
913 */
914
915 sblocks_for_recheck = kcalloc(BTRFS_MAX_MIRRORS,
916 sizeof(*sblocks_for_recheck), GFP_NOFS);
917 if (!sblocks_for_recheck) {
918 spin_lock(&sctx->stat_lock);
919 sctx->stat.malloc_errors++;
920 sctx->stat.read_errors++;
921 sctx->stat.uncorrectable_errors++;
922 spin_unlock(&sctx->stat_lock);
923 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
924 goto out;
925 }
926
927 /* setup the context, map the logical blocks and alloc the pages */
928 ret = scrub_setup_recheck_block(sblock_to_check, sblocks_for_recheck);
929 if (ret) {
930 spin_lock(&sctx->stat_lock);
931 sctx->stat.read_errors++;
932 sctx->stat.uncorrectable_errors++;
933 spin_unlock(&sctx->stat_lock);
934 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
935 goto out;
936 }
937 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
938 sblock_bad = sblocks_for_recheck + failed_mirror_index;
939
940 /* build and submit the bios for the failed mirror, check checksums */
941 scrub_recheck_block(fs_info, sblock_bad, 1);
942
943 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
944 sblock_bad->no_io_error_seen) {
945 /*
946 * the error disappeared after reading page by page, or
947 * the area was part of a huge bio and other parts of the
948 * bio caused I/O errors, or the block layer merged several
949 * read requests into one and the error is caused by a
950 * different bio (usually one of the two latter cases is
951 * the cause)
952 */
953 spin_lock(&sctx->stat_lock);
954 sctx->stat.unverified_errors++;
955 sblock_to_check->data_corrected = 1;
956 spin_unlock(&sctx->stat_lock);
957
958 if (sctx->is_dev_replace)
959 scrub_write_block_to_dev_replace(sblock_bad);
960 goto out;
961 }
962
963 if (!sblock_bad->no_io_error_seen) {
964 spin_lock(&sctx->stat_lock);
965 sctx->stat.read_errors++;
966 spin_unlock(&sctx->stat_lock);
967 if (__ratelimit(&_rs))
968 scrub_print_warning("i/o error", sblock_to_check);
969 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
970 } else if (sblock_bad->checksum_error) {
971 spin_lock(&sctx->stat_lock);
972 sctx->stat.csum_errors++;
973 spin_unlock(&sctx->stat_lock);
974 if (__ratelimit(&_rs))
975 scrub_print_warning("checksum error", sblock_to_check);
976 btrfs_dev_stat_inc_and_print(dev,
977 BTRFS_DEV_STAT_CORRUPTION_ERRS);
978 } else if (sblock_bad->header_error) {
979 spin_lock(&sctx->stat_lock);
980 sctx->stat.verify_errors++;
981 spin_unlock(&sctx->stat_lock);
982 if (__ratelimit(&_rs))
983 scrub_print_warning("checksum/header error",
984 sblock_to_check);
985 if (sblock_bad->generation_error)
986 btrfs_dev_stat_inc_and_print(dev,
987 BTRFS_DEV_STAT_GENERATION_ERRS);
988 else
989 btrfs_dev_stat_inc_and_print(dev,
990 BTRFS_DEV_STAT_CORRUPTION_ERRS);
991 }
992
993 if (sctx->readonly) {
994 ASSERT(!sctx->is_dev_replace);
995 goto out;
996 }
997
998 /*
999 * now build and submit the bios for the other mirrors, check
1000 * checksums.
1001 * First try to pick the mirror which is completely without I/O
1002 * errors and also does not have a checksum error.
1003 * If one is found, and if a checksum is present, the full block
1004 * that is known to contain an error is rewritten. Afterwards
1005 * the block is known to be corrected.
1006 * If a mirror is found which is completely correct, and no
1007 * checksum is present, only those pages are rewritten that had
1008 * an I/O error in the block to be repaired, since it cannot be
1009 * determined, which copy of the other pages is better (and it
1010 * could happen otherwise that a correct page would be
1011 * overwritten by a bad one).
1012 */
1013 for (mirror_index = 0; ;mirror_index++) {
1014 struct scrub_block *sblock_other;
1015
1016 if (mirror_index == failed_mirror_index)
1017 continue;
1018
1019 /* raid56's mirror can be more than BTRFS_MAX_MIRRORS */
1020 if (!scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1021 if (mirror_index >= BTRFS_MAX_MIRRORS)
1022 break;
1023 if (!sblocks_for_recheck[mirror_index].page_count)
1024 break;
1025
1026 sblock_other = sblocks_for_recheck + mirror_index;
1027 } else {
1028 struct scrub_recover *r = sblock_bad->pagev[0]->recover;
1029 int max_allowed = r->bbio->num_stripes -
1030 r->bbio->num_tgtdevs;
1031
1032 if (mirror_index >= max_allowed)
1033 break;
1034 if (!sblocks_for_recheck[1].page_count)
1035 break;
1036
1037 ASSERT(failed_mirror_index == 0);
1038 sblock_other = sblocks_for_recheck + 1;
1039 sblock_other->pagev[0]->mirror_num = 1 + mirror_index;
1040 }
1041
1042 /* build and submit the bios, check checksums */
1043 scrub_recheck_block(fs_info, sblock_other, 0);
1044
1045 if (!sblock_other->header_error &&
1046 !sblock_other->checksum_error &&
1047 sblock_other->no_io_error_seen) {
1048 if (sctx->is_dev_replace) {
1049 scrub_write_block_to_dev_replace(sblock_other);
1050 goto corrected_error;
1051 } else {
1052 ret = scrub_repair_block_from_good_copy(
1053 sblock_bad, sblock_other);
1054 if (!ret)
1055 goto corrected_error;
1056 }
1057 }
1058 }
1059
1060 if (sblock_bad->no_io_error_seen && !sctx->is_dev_replace)
1061 goto did_not_correct_error;
1062
1063 /*
1064 * In case of I/O errors in the area that is supposed to be
1065 * repaired, continue by picking good copies of those pages.
1066 * Select the good pages from mirrors to rewrite bad pages from
1067 * the area to fix. Afterwards verify the checksum of the block
1068 * that is supposed to be repaired. This verification step is
1069 * only done for the purpose of statistic counting and for the
1070 * final scrub report, whether errors remain.
1071 * A perfect algorithm could make use of the checksum and try
1072 * all possible combinations of pages from the different mirrors
1073 * until the checksum verification succeeds. For example, when
1074 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
1075 * of mirror #2 is readable but the final checksum test fails,
1076 * then the 2nd page of mirror #3 could be tried, whether now
1077 * the final checksum succeeds. But this would be a rare
1078 * exception and is therefore not implemented. At least it is
1079 * avoided that the good copy is overwritten.
1080 * A more useful improvement would be to pick the sectors
1081 * without I/O error based on sector sizes (512 bytes on legacy
1082 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
1083 * mirror could be repaired by taking 512 byte of a different
1084 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
1085 * area are unreadable.
1086 */
1087 success = 1;
1088 for (page_num = 0; page_num < sblock_bad->page_count;
1089 page_num++) {
1090 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1091 struct scrub_block *sblock_other = NULL;
1092
1093 /* skip no-io-error page in scrub */
1094 if (!page_bad->io_error && !sctx->is_dev_replace)
1095 continue;
1096
1097 if (scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1098 /*
1099 * In case of dev replace, if raid56 rebuild process
1100 * didn't work out correct data, then copy the content
1101 * in sblock_bad to make sure target device is identical
1102 * to source device, instead of writing garbage data in
1103 * sblock_for_recheck array to target device.
1104 */
1105 sblock_other = NULL;
1106 } else if (page_bad->io_error) {
1107 /* try to find no-io-error page in mirrors */
1108 for (mirror_index = 0;
1109 mirror_index < BTRFS_MAX_MIRRORS &&
1110 sblocks_for_recheck[mirror_index].page_count > 0;
1111 mirror_index++) {
1112 if (!sblocks_for_recheck[mirror_index].
1113 pagev[page_num]->io_error) {
1114 sblock_other = sblocks_for_recheck +
1115 mirror_index;
1116 break;
1117 }
1118 }
1119 if (!sblock_other)
1120 success = 0;
1121 }
1122
1123 if (sctx->is_dev_replace) {
1124 /*
1125 * did not find a mirror to fetch the page
1126 * from. scrub_write_page_to_dev_replace()
1127 * handles this case (page->io_error), by
1128 * filling the block with zeros before
1129 * submitting the write request
1130 */
1131 if (!sblock_other)
1132 sblock_other = sblock_bad;
1133
1134 if (scrub_write_page_to_dev_replace(sblock_other,
1135 page_num) != 0) {
1136 btrfs_dev_replace_stats_inc(
1137 &fs_info->dev_replace.num_write_errors);
1138 success = 0;
1139 }
1140 } else if (sblock_other) {
1141 ret = scrub_repair_page_from_good_copy(sblock_bad,
1142 sblock_other,
1143 page_num, 0);
1144 if (0 == ret)
1145 page_bad->io_error = 0;
1146 else
1147 success = 0;
1148 }
1149 }
1150
1151 if (success && !sctx->is_dev_replace) {
1152 if (is_metadata || have_csum) {
1153 /*
1154 * need to verify the checksum now that all
1155 * sectors on disk are repaired (the write
1156 * request for data to be repaired is on its way).
1157 * Just be lazy and use scrub_recheck_block()
1158 * which re-reads the data before the checksum
1159 * is verified, but most likely the data comes out
1160 * of the page cache.
1161 */
1162 scrub_recheck_block(fs_info, sblock_bad, 1);
1163 if (!sblock_bad->header_error &&
1164 !sblock_bad->checksum_error &&
1165 sblock_bad->no_io_error_seen)
1166 goto corrected_error;
1167 else
1168 goto did_not_correct_error;
1169 } else {
1170 corrected_error:
1171 spin_lock(&sctx->stat_lock);
1172 sctx->stat.corrected_errors++;
1173 sblock_to_check->data_corrected = 1;
1174 spin_unlock(&sctx->stat_lock);
1175 btrfs_err_rl_in_rcu(fs_info,
1176 "fixed up error at logical %llu on dev %s",
1177 logical, rcu_str_deref(dev->name));
1178 }
1179 } else {
1180 did_not_correct_error:
1181 spin_lock(&sctx->stat_lock);
1182 sctx->stat.uncorrectable_errors++;
1183 spin_unlock(&sctx->stat_lock);
1184 btrfs_err_rl_in_rcu(fs_info,
1185 "unable to fixup (regular) error at logical %llu on dev %s",
1186 logical, rcu_str_deref(dev->name));
1187 }
1188
1189 out:
1190 if (sblocks_for_recheck) {
1191 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
1192 mirror_index++) {
1193 struct scrub_block *sblock = sblocks_for_recheck +
1194 mirror_index;
1195 struct scrub_recover *recover;
1196 int page_index;
1197
1198 for (page_index = 0; page_index < sblock->page_count;
1199 page_index++) {
1200 sblock->pagev[page_index]->sblock = NULL;
1201 recover = sblock->pagev[page_index]->recover;
1202 if (recover) {
1203 scrub_put_recover(fs_info, recover);
1204 sblock->pagev[page_index]->recover =
1205 NULL;
1206 }
1207 scrub_page_put(sblock->pagev[page_index]);
1208 }
1209 }
1210 kfree(sblocks_for_recheck);
1211 }
1212
1213 ret = unlock_full_stripe(fs_info, logical, full_stripe_locked);
1214 if (ret < 0)
1215 return ret;
1216 return 0;
1217 }
1218
1219 static inline int scrub_nr_raid_mirrors(struct btrfs_bio *bbio)
1220 {
1221 if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID5)
1222 return 2;
1223 else if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID6)
1224 return 3;
1225 else
1226 return (int)bbio->num_stripes;
1227 }
1228
1229 static inline void scrub_stripe_index_and_offset(u64 logical, u64 map_type,
1230 u64 *raid_map,
1231 u64 mapped_length,
1232 int nstripes, int mirror,
1233 int *stripe_index,
1234 u64 *stripe_offset)
1235 {
1236 int i;
1237
1238 if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
1239 /* RAID5/6 */
1240 for (i = 0; i < nstripes; i++) {
1241 if (raid_map[i] == RAID6_Q_STRIPE ||
1242 raid_map[i] == RAID5_P_STRIPE)
1243 continue;
1244
1245 if (logical >= raid_map[i] &&
1246 logical < raid_map[i] + mapped_length)
1247 break;
1248 }
1249
1250 *stripe_index = i;
1251 *stripe_offset = logical - raid_map[i];
1252 } else {
1253 /* The other RAID type */
1254 *stripe_index = mirror;
1255 *stripe_offset = 0;
1256 }
1257 }
1258
1259 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
1260 struct scrub_block *sblocks_for_recheck)
1261 {
1262 struct scrub_ctx *sctx = original_sblock->sctx;
1263 struct btrfs_fs_info *fs_info = sctx->fs_info;
1264 u64 length = original_sblock->page_count * PAGE_SIZE;
1265 u64 logical = original_sblock->pagev[0]->logical;
1266 u64 generation = original_sblock->pagev[0]->generation;
1267 u64 flags = original_sblock->pagev[0]->flags;
1268 u64 have_csum = original_sblock->pagev[0]->have_csum;
1269 struct scrub_recover *recover;
1270 struct btrfs_bio *bbio;
1271 u64 sublen;
1272 u64 mapped_length;
1273 u64 stripe_offset;
1274 int stripe_index;
1275 int page_index = 0;
1276 int mirror_index;
1277 int nmirrors;
1278 int ret;
1279
1280 /*
1281 * note: the two members refs and outstanding_pages
1282 * are not used (and not set) in the blocks that are used for
1283 * the recheck procedure
1284 */
1285
1286 while (length > 0) {
1287 sublen = min_t(u64, length, PAGE_SIZE);
1288 mapped_length = sublen;
1289 bbio = NULL;
1290
1291 /*
1292 * with a length of PAGE_SIZE, each returned stripe
1293 * represents one mirror
1294 */
1295 btrfs_bio_counter_inc_blocked(fs_info);
1296 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS,
1297 logical, &mapped_length, &bbio);
1298 if (ret || !bbio || mapped_length < sublen) {
1299 btrfs_put_bbio(bbio);
1300 btrfs_bio_counter_dec(fs_info);
1301 return -EIO;
1302 }
1303
1304 recover = kzalloc(sizeof(struct scrub_recover), GFP_NOFS);
1305 if (!recover) {
1306 btrfs_put_bbio(bbio);
1307 btrfs_bio_counter_dec(fs_info);
1308 return -ENOMEM;
1309 }
1310
1311 refcount_set(&recover->refs, 1);
1312 recover->bbio = bbio;
1313 recover->map_length = mapped_length;
1314
1315 BUG_ON(page_index >= SCRUB_MAX_PAGES_PER_BLOCK);
1316
1317 nmirrors = min(scrub_nr_raid_mirrors(bbio), BTRFS_MAX_MIRRORS);
1318
1319 for (mirror_index = 0; mirror_index < nmirrors;
1320 mirror_index++) {
1321 struct scrub_block *sblock;
1322 struct scrub_page *page;
1323
1324 sblock = sblocks_for_recheck + mirror_index;
1325 sblock->sctx = sctx;
1326
1327 page = kzalloc(sizeof(*page), GFP_NOFS);
1328 if (!page) {
1329 leave_nomem:
1330 spin_lock(&sctx->stat_lock);
1331 sctx->stat.malloc_errors++;
1332 spin_unlock(&sctx->stat_lock);
1333 scrub_put_recover(fs_info, recover);
1334 return -ENOMEM;
1335 }
1336 scrub_page_get(page);
1337 sblock->pagev[page_index] = page;
1338 page->sblock = sblock;
1339 page->flags = flags;
1340 page->generation = generation;
1341 page->logical = logical;
1342 page->have_csum = have_csum;
1343 if (have_csum)
1344 memcpy(page->csum,
1345 original_sblock->pagev[0]->csum,
1346 sctx->csum_size);
1347
1348 scrub_stripe_index_and_offset(logical,
1349 bbio->map_type,
1350 bbio->raid_map,
1351 mapped_length,
1352 bbio->num_stripes -
1353 bbio->num_tgtdevs,
1354 mirror_index,
1355 &stripe_index,
1356 &stripe_offset);
1357 page->physical = bbio->stripes[stripe_index].physical +
1358 stripe_offset;
1359 page->dev = bbio->stripes[stripe_index].dev;
1360
1361 BUG_ON(page_index >= original_sblock->page_count);
1362 page->physical_for_dev_replace =
1363 original_sblock->pagev[page_index]->
1364 physical_for_dev_replace;
1365 /* for missing devices, dev->bdev is NULL */
1366 page->mirror_num = mirror_index + 1;
1367 sblock->page_count++;
1368 page->page = alloc_page(GFP_NOFS);
1369 if (!page->page)
1370 goto leave_nomem;
1371
1372 scrub_get_recover(recover);
1373 page->recover = recover;
1374 }
1375 scrub_put_recover(fs_info, recover);
1376 length -= sublen;
1377 logical += sublen;
1378 page_index++;
1379 }
1380
1381 return 0;
1382 }
1383
1384 static void scrub_bio_wait_endio(struct bio *bio)
1385 {
1386 complete(bio->bi_private);
1387 }
1388
1389 static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
1390 struct bio *bio,
1391 struct scrub_page *page)
1392 {
1393 DECLARE_COMPLETION_ONSTACK(done);
1394 int ret;
1395 int mirror_num;
1396
1397 bio->bi_iter.bi_sector = page->logical >> 9;
1398 bio->bi_private = &done;
1399 bio->bi_end_io = scrub_bio_wait_endio;
1400
1401 mirror_num = page->sblock->pagev[0]->mirror_num;
1402 ret = raid56_parity_recover(fs_info, bio, page->recover->bbio,
1403 page->recover->map_length,
1404 mirror_num, 0);
1405 if (ret)
1406 return ret;
1407
1408 wait_for_completion_io(&done);
1409 return blk_status_to_errno(bio->bi_status);
1410 }
1411
1412 static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info,
1413 struct scrub_block *sblock)
1414 {
1415 struct scrub_page *first_page = sblock->pagev[0];
1416 struct bio *bio;
1417 int page_num;
1418
1419 /* All pages in sblock belong to the same stripe on the same device. */
1420 ASSERT(first_page->dev);
1421 if (!first_page->dev->bdev)
1422 goto out;
1423
1424 bio = btrfs_io_bio_alloc(BIO_MAX_PAGES);
1425 bio_set_dev(bio, first_page->dev->bdev);
1426
1427 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1428 struct scrub_page *page = sblock->pagev[page_num];
1429
1430 WARN_ON(!page->page);
1431 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1432 }
1433
1434 if (scrub_submit_raid56_bio_wait(fs_info, bio, first_page)) {
1435 bio_put(bio);
1436 goto out;
1437 }
1438
1439 bio_put(bio);
1440
1441 scrub_recheck_block_checksum(sblock);
1442
1443 return;
1444 out:
1445 for (page_num = 0; page_num < sblock->page_count; page_num++)
1446 sblock->pagev[page_num]->io_error = 1;
1447
1448 sblock->no_io_error_seen = 0;
1449 }
1450
1451 /*
1452 * this function will check the on disk data for checksum errors, header
1453 * errors and read I/O errors. If any I/O errors happen, the exact pages
1454 * which are errored are marked as being bad. The goal is to enable scrub
1455 * to take those pages that are not errored from all the mirrors so that
1456 * the pages that are errored in the just handled mirror can be repaired.
1457 */
1458 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
1459 struct scrub_block *sblock,
1460 int retry_failed_mirror)
1461 {
1462 int page_num;
1463
1464 sblock->no_io_error_seen = 1;
1465
1466 /* short cut for raid56 */
1467 if (!retry_failed_mirror && scrub_is_page_on_raid56(sblock->pagev[0]))
1468 return scrub_recheck_block_on_raid56(fs_info, sblock);
1469
1470 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1471 struct bio *bio;
1472 struct scrub_page *page = sblock->pagev[page_num];
1473
1474 if (page->dev->bdev == NULL) {
1475 page->io_error = 1;
1476 sblock->no_io_error_seen = 0;
1477 continue;
1478 }
1479
1480 WARN_ON(!page->page);
1481 bio = btrfs_io_bio_alloc(1);
1482 bio_set_dev(bio, page->dev->bdev);
1483
1484 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1485 bio->bi_iter.bi_sector = page->physical >> 9;
1486 bio->bi_opf = REQ_OP_READ;
1487
1488 if (btrfsic_submit_bio_wait(bio)) {
1489 page->io_error = 1;
1490 sblock->no_io_error_seen = 0;
1491 }
1492
1493 bio_put(bio);
1494 }
1495
1496 if (sblock->no_io_error_seen)
1497 scrub_recheck_block_checksum(sblock);
1498 }
1499
1500 static inline int scrub_check_fsid(u8 fsid[],
1501 struct scrub_page *spage)
1502 {
1503 struct btrfs_fs_devices *fs_devices = spage->dev->fs_devices;
1504 int ret;
1505
1506 ret = memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1507 return !ret;
1508 }
1509
1510 static void scrub_recheck_block_checksum(struct scrub_block *sblock)
1511 {
1512 sblock->header_error = 0;
1513 sblock->checksum_error = 0;
1514 sblock->generation_error = 0;
1515
1516 if (sblock->pagev[0]->flags & BTRFS_EXTENT_FLAG_DATA)
1517 scrub_checksum_data(sblock);
1518 else
1519 scrub_checksum_tree_block(sblock);
1520 }
1521
1522 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1523 struct scrub_block *sblock_good)
1524 {
1525 int page_num;
1526 int ret = 0;
1527
1528 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1529 int ret_sub;
1530
1531 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1532 sblock_good,
1533 page_num, 1);
1534 if (ret_sub)
1535 ret = ret_sub;
1536 }
1537
1538 return ret;
1539 }
1540
1541 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1542 struct scrub_block *sblock_good,
1543 int page_num, int force_write)
1544 {
1545 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1546 struct scrub_page *page_good = sblock_good->pagev[page_num];
1547 struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info;
1548
1549 BUG_ON(page_bad->page == NULL);
1550 BUG_ON(page_good->page == NULL);
1551 if (force_write || sblock_bad->header_error ||
1552 sblock_bad->checksum_error || page_bad->io_error) {
1553 struct bio *bio;
1554 int ret;
1555
1556 if (!page_bad->dev->bdev) {
1557 btrfs_warn_rl(fs_info,
1558 "scrub_repair_page_from_good_copy(bdev == NULL) is unexpected");
1559 return -EIO;
1560 }
1561
1562 bio = btrfs_io_bio_alloc(1);
1563 bio_set_dev(bio, page_bad->dev->bdev);
1564 bio->bi_iter.bi_sector = page_bad->physical >> 9;
1565 bio->bi_opf = REQ_OP_WRITE;
1566
1567 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1568 if (PAGE_SIZE != ret) {
1569 bio_put(bio);
1570 return -EIO;
1571 }
1572
1573 if (btrfsic_submit_bio_wait(bio)) {
1574 btrfs_dev_stat_inc_and_print(page_bad->dev,
1575 BTRFS_DEV_STAT_WRITE_ERRS);
1576 btrfs_dev_replace_stats_inc(
1577 &fs_info->dev_replace.num_write_errors);
1578 bio_put(bio);
1579 return -EIO;
1580 }
1581 bio_put(bio);
1582 }
1583
1584 return 0;
1585 }
1586
1587 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
1588 {
1589 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
1590 int page_num;
1591
1592 /*
1593 * This block is used for the check of the parity on the source device,
1594 * so the data needn't be written into the destination device.
1595 */
1596 if (sblock->sparity)
1597 return;
1598
1599 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1600 int ret;
1601
1602 ret = scrub_write_page_to_dev_replace(sblock, page_num);
1603 if (ret)
1604 btrfs_dev_replace_stats_inc(
1605 &fs_info->dev_replace.num_write_errors);
1606 }
1607 }
1608
1609 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
1610 int page_num)
1611 {
1612 struct scrub_page *spage = sblock->pagev[page_num];
1613
1614 BUG_ON(spage->page == NULL);
1615 if (spage->io_error) {
1616 void *mapped_buffer = kmap_atomic(spage->page);
1617
1618 clear_page(mapped_buffer);
1619 flush_dcache_page(spage->page);
1620 kunmap_atomic(mapped_buffer);
1621 }
1622 return scrub_add_page_to_wr_bio(sblock->sctx, spage);
1623 }
1624
1625 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
1626 struct scrub_page *spage)
1627 {
1628 struct scrub_bio *sbio;
1629 int ret;
1630
1631 mutex_lock(&sctx->wr_lock);
1632 again:
1633 if (!sctx->wr_curr_bio) {
1634 unsigned int nofs_flag;
1635
1636 /*
1637 * We must use GFP_NOFS because the scrub task might be waiting
1638 * for a worker task executing this function and in turn a
1639 * transaction commit might be waiting the scrub task to pause
1640 * (which needs to wait for all the worker tasks to complete
1641 * before pausing).
1642 */
1643 nofs_flag = memalloc_nofs_save();
1644 sctx->wr_curr_bio = kzalloc(sizeof(*sctx->wr_curr_bio),
1645 GFP_KERNEL);
1646 memalloc_nofs_restore(nofs_flag);
1647 if (!sctx->wr_curr_bio) {
1648 mutex_unlock(&sctx->wr_lock);
1649 return -ENOMEM;
1650 }
1651 sctx->wr_curr_bio->sctx = sctx;
1652 sctx->wr_curr_bio->page_count = 0;
1653 }
1654 sbio = sctx->wr_curr_bio;
1655 if (sbio->page_count == 0) {
1656 struct bio *bio;
1657
1658 sbio->physical = spage->physical_for_dev_replace;
1659 sbio->logical = spage->logical;
1660 sbio->dev = sctx->wr_tgtdev;
1661 bio = sbio->bio;
1662 if (!bio) {
1663 bio = btrfs_io_bio_alloc(sctx->pages_per_wr_bio);
1664 sbio->bio = bio;
1665 }
1666
1667 bio->bi_private = sbio;
1668 bio->bi_end_io = scrub_wr_bio_end_io;
1669 bio_set_dev(bio, sbio->dev->bdev);
1670 bio->bi_iter.bi_sector = sbio->physical >> 9;
1671 bio->bi_opf = REQ_OP_WRITE;
1672 sbio->status = 0;
1673 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1674 spage->physical_for_dev_replace ||
1675 sbio->logical + sbio->page_count * PAGE_SIZE !=
1676 spage->logical) {
1677 scrub_wr_submit(sctx);
1678 goto again;
1679 }
1680
1681 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1682 if (ret != PAGE_SIZE) {
1683 if (sbio->page_count < 1) {
1684 bio_put(sbio->bio);
1685 sbio->bio = NULL;
1686 mutex_unlock(&sctx->wr_lock);
1687 return -EIO;
1688 }
1689 scrub_wr_submit(sctx);
1690 goto again;
1691 }
1692
1693 sbio->pagev[sbio->page_count] = spage;
1694 scrub_page_get(spage);
1695 sbio->page_count++;
1696 if (sbio->page_count == sctx->pages_per_wr_bio)
1697 scrub_wr_submit(sctx);
1698 mutex_unlock(&sctx->wr_lock);
1699
1700 return 0;
1701 }
1702
1703 static void scrub_wr_submit(struct scrub_ctx *sctx)
1704 {
1705 struct scrub_bio *sbio;
1706
1707 if (!sctx->wr_curr_bio)
1708 return;
1709
1710 sbio = sctx->wr_curr_bio;
1711 sctx->wr_curr_bio = NULL;
1712 WARN_ON(!sbio->bio->bi_disk);
1713 scrub_pending_bio_inc(sctx);
1714 /* process all writes in a single worker thread. Then the block layer
1715 * orders the requests before sending them to the driver which
1716 * doubled the write performance on spinning disks when measured
1717 * with Linux 3.5 */
1718 btrfsic_submit_bio(sbio->bio);
1719 }
1720
1721 static void scrub_wr_bio_end_io(struct bio *bio)
1722 {
1723 struct scrub_bio *sbio = bio->bi_private;
1724 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
1725
1726 sbio->status = bio->bi_status;
1727 sbio->bio = bio;
1728
1729 btrfs_init_work(&sbio->work, btrfs_scrubwrc_helper,
1730 scrub_wr_bio_end_io_worker, NULL, NULL);
1731 btrfs_queue_work(fs_info->scrub_wr_completion_workers, &sbio->work);
1732 }
1733
1734 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work)
1735 {
1736 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1737 struct scrub_ctx *sctx = sbio->sctx;
1738 int i;
1739
1740 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO);
1741 if (sbio->status) {
1742 struct btrfs_dev_replace *dev_replace =
1743 &sbio->sctx->fs_info->dev_replace;
1744
1745 for (i = 0; i < sbio->page_count; i++) {
1746 struct scrub_page *spage = sbio->pagev[i];
1747
1748 spage->io_error = 1;
1749 btrfs_dev_replace_stats_inc(&dev_replace->
1750 num_write_errors);
1751 }
1752 }
1753
1754 for (i = 0; i < sbio->page_count; i++)
1755 scrub_page_put(sbio->pagev[i]);
1756
1757 bio_put(sbio->bio);
1758 kfree(sbio);
1759 scrub_pending_bio_dec(sctx);
1760 }
1761
1762 static int scrub_checksum(struct scrub_block *sblock)
1763 {
1764 u64 flags;
1765 int ret;
1766
1767 /*
1768 * No need to initialize these stats currently,
1769 * because this function only use return value
1770 * instead of these stats value.
1771 *
1772 * Todo:
1773 * always use stats
1774 */
1775 sblock->header_error = 0;
1776 sblock->generation_error = 0;
1777 sblock->checksum_error = 0;
1778
1779 WARN_ON(sblock->page_count < 1);
1780 flags = sblock->pagev[0]->flags;
1781 ret = 0;
1782 if (flags & BTRFS_EXTENT_FLAG_DATA)
1783 ret = scrub_checksum_data(sblock);
1784 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1785 ret = scrub_checksum_tree_block(sblock);
1786 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1787 (void)scrub_checksum_super(sblock);
1788 else
1789 WARN_ON(1);
1790 if (ret)
1791 scrub_handle_errored_block(sblock);
1792
1793 return ret;
1794 }
1795
1796 static int scrub_checksum_data(struct scrub_block *sblock)
1797 {
1798 struct scrub_ctx *sctx = sblock->sctx;
1799 u8 csum[BTRFS_CSUM_SIZE];
1800 u8 *on_disk_csum;
1801 struct page *page;
1802 void *buffer;
1803 u32 crc = ~(u32)0;
1804 u64 len;
1805 int index;
1806
1807 BUG_ON(sblock->page_count < 1);
1808 if (!sblock->pagev[0]->have_csum)
1809 return 0;
1810
1811 on_disk_csum = sblock->pagev[0]->csum;
1812 page = sblock->pagev[0]->page;
1813 buffer = kmap_atomic(page);
1814
1815 len = sctx->fs_info->sectorsize;
1816 index = 0;
1817 for (;;) {
1818 u64 l = min_t(u64, len, PAGE_SIZE);
1819
1820 crc = btrfs_csum_data(buffer, crc, l);
1821 kunmap_atomic(buffer);
1822 len -= l;
1823 if (len == 0)
1824 break;
1825 index++;
1826 BUG_ON(index >= sblock->page_count);
1827 BUG_ON(!sblock->pagev[index]->page);
1828 page = sblock->pagev[index]->page;
1829 buffer = kmap_atomic(page);
1830 }
1831
1832 btrfs_csum_final(crc, csum);
1833 if (memcmp(csum, on_disk_csum, sctx->csum_size))
1834 sblock->checksum_error = 1;
1835
1836 return sblock->checksum_error;
1837 }
1838
1839 static int scrub_checksum_tree_block(struct scrub_block *sblock)
1840 {
1841 struct scrub_ctx *sctx = sblock->sctx;
1842 struct btrfs_header *h;
1843 struct btrfs_fs_info *fs_info = sctx->fs_info;
1844 u8 calculated_csum[BTRFS_CSUM_SIZE];
1845 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1846 struct page *page;
1847 void *mapped_buffer;
1848 u64 mapped_size;
1849 void *p;
1850 u32 crc = ~(u32)0;
1851 u64 len;
1852 int index;
1853
1854 BUG_ON(sblock->page_count < 1);
1855 page = sblock->pagev[0]->page;
1856 mapped_buffer = kmap_atomic(page);
1857 h = (struct btrfs_header *)mapped_buffer;
1858 memcpy(on_disk_csum, h->csum, sctx->csum_size);
1859
1860 /*
1861 * we don't use the getter functions here, as we
1862 * a) don't have an extent buffer and
1863 * b) the page is already kmapped
1864 */
1865 if (sblock->pagev[0]->logical != btrfs_stack_header_bytenr(h))
1866 sblock->header_error = 1;
1867
1868 if (sblock->pagev[0]->generation != btrfs_stack_header_generation(h)) {
1869 sblock->header_error = 1;
1870 sblock->generation_error = 1;
1871 }
1872
1873 if (!scrub_check_fsid(h->fsid, sblock->pagev[0]))
1874 sblock->header_error = 1;
1875
1876 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1877 BTRFS_UUID_SIZE))
1878 sblock->header_error = 1;
1879
1880 len = sctx->fs_info->nodesize - BTRFS_CSUM_SIZE;
1881 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1882 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1883 index = 0;
1884 for (;;) {
1885 u64 l = min_t(u64, len, mapped_size);
1886
1887 crc = btrfs_csum_data(p, crc, l);
1888 kunmap_atomic(mapped_buffer);
1889 len -= l;
1890 if (len == 0)
1891 break;
1892 index++;
1893 BUG_ON(index >= sblock->page_count);
1894 BUG_ON(!sblock->pagev[index]->page);
1895 page = sblock->pagev[index]->page;
1896 mapped_buffer = kmap_atomic(page);
1897 mapped_size = PAGE_SIZE;
1898 p = mapped_buffer;
1899 }
1900
1901 btrfs_csum_final(crc, calculated_csum);
1902 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1903 sblock->checksum_error = 1;
1904
1905 return sblock->header_error || sblock->checksum_error;
1906 }
1907
1908 static int scrub_checksum_super(struct scrub_block *sblock)
1909 {
1910 struct btrfs_super_block *s;
1911 struct scrub_ctx *sctx = sblock->sctx;
1912 u8 calculated_csum[BTRFS_CSUM_SIZE];
1913 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1914 struct page *page;
1915 void *mapped_buffer;
1916 u64 mapped_size;
1917 void *p;
1918 u32 crc = ~(u32)0;
1919 int fail_gen = 0;
1920 int fail_cor = 0;
1921 u64 len;
1922 int index;
1923
1924 BUG_ON(sblock->page_count < 1);
1925 page = sblock->pagev[0]->page;
1926 mapped_buffer = kmap_atomic(page);
1927 s = (struct btrfs_super_block *)mapped_buffer;
1928 memcpy(on_disk_csum, s->csum, sctx->csum_size);
1929
1930 if (sblock->pagev[0]->logical != btrfs_super_bytenr(s))
1931 ++fail_cor;
1932
1933 if (sblock->pagev[0]->generation != btrfs_super_generation(s))
1934 ++fail_gen;
1935
1936 if (!scrub_check_fsid(s->fsid, sblock->pagev[0]))
1937 ++fail_cor;
1938
1939 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1940 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1941 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1942 index = 0;
1943 for (;;) {
1944 u64 l = min_t(u64, len, mapped_size);
1945
1946 crc = btrfs_csum_data(p, crc, l);
1947 kunmap_atomic(mapped_buffer);
1948 len -= l;
1949 if (len == 0)
1950 break;
1951 index++;
1952 BUG_ON(index >= sblock->page_count);
1953 BUG_ON(!sblock->pagev[index]->page);
1954 page = sblock->pagev[index]->page;
1955 mapped_buffer = kmap_atomic(page);
1956 mapped_size = PAGE_SIZE;
1957 p = mapped_buffer;
1958 }
1959
1960 btrfs_csum_final(crc, calculated_csum);
1961 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1962 ++fail_cor;
1963
1964 if (fail_cor + fail_gen) {
1965 /*
1966 * if we find an error in a super block, we just report it.
1967 * They will get written with the next transaction commit
1968 * anyway
1969 */
1970 spin_lock(&sctx->stat_lock);
1971 ++sctx->stat.super_errors;
1972 spin_unlock(&sctx->stat_lock);
1973 if (fail_cor)
1974 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1975 BTRFS_DEV_STAT_CORRUPTION_ERRS);
1976 else
1977 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1978 BTRFS_DEV_STAT_GENERATION_ERRS);
1979 }
1980
1981 return fail_cor + fail_gen;
1982 }
1983
1984 static void scrub_block_get(struct scrub_block *sblock)
1985 {
1986 refcount_inc(&sblock->refs);
1987 }
1988
1989 static void scrub_block_put(struct scrub_block *sblock)
1990 {
1991 if (refcount_dec_and_test(&sblock->refs)) {
1992 int i;
1993
1994 if (sblock->sparity)
1995 scrub_parity_put(sblock->sparity);
1996
1997 for (i = 0; i < sblock->page_count; i++)
1998 scrub_page_put(sblock->pagev[i]);
1999 kfree(sblock);
2000 }
2001 }
2002
2003 static void scrub_page_get(struct scrub_page *spage)
2004 {
2005 atomic_inc(&spage->refs);
2006 }
2007
2008 static void scrub_page_put(struct scrub_page *spage)
2009 {
2010 if (atomic_dec_and_test(&spage->refs)) {
2011 if (spage->page)
2012 __free_page(spage->page);
2013 kfree(spage);
2014 }
2015 }
2016
2017 static void scrub_submit(struct scrub_ctx *sctx)
2018 {
2019 struct scrub_bio *sbio;
2020
2021 if (sctx->curr == -1)
2022 return;
2023
2024 sbio = sctx->bios[sctx->curr];
2025 sctx->curr = -1;
2026 scrub_pending_bio_inc(sctx);
2027 btrfsic_submit_bio(sbio->bio);
2028 }
2029
2030 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
2031 struct scrub_page *spage)
2032 {
2033 struct scrub_block *sblock = spage->sblock;
2034 struct scrub_bio *sbio;
2035 int ret;
2036
2037 again:
2038 /*
2039 * grab a fresh bio or wait for one to become available
2040 */
2041 while (sctx->curr == -1) {
2042 spin_lock(&sctx->list_lock);
2043 sctx->curr = sctx->first_free;
2044 if (sctx->curr != -1) {
2045 sctx->first_free = sctx->bios[sctx->curr]->next_free;
2046 sctx->bios[sctx->curr]->next_free = -1;
2047 sctx->bios[sctx->curr]->page_count = 0;
2048 spin_unlock(&sctx->list_lock);
2049 } else {
2050 spin_unlock(&sctx->list_lock);
2051 wait_event(sctx->list_wait, sctx->first_free != -1);
2052 }
2053 }
2054 sbio = sctx->bios[sctx->curr];
2055 if (sbio->page_count == 0) {
2056 struct bio *bio;
2057
2058 sbio->physical = spage->physical;
2059 sbio->logical = spage->logical;
2060 sbio->dev = spage->dev;
2061 bio = sbio->bio;
2062 if (!bio) {
2063 bio = btrfs_io_bio_alloc(sctx->pages_per_rd_bio);
2064 sbio->bio = bio;
2065 }
2066
2067 bio->bi_private = sbio;
2068 bio->bi_end_io = scrub_bio_end_io;
2069 bio_set_dev(bio, sbio->dev->bdev);
2070 bio->bi_iter.bi_sector = sbio->physical >> 9;
2071 bio->bi_opf = REQ_OP_READ;
2072 sbio->status = 0;
2073 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
2074 spage->physical ||
2075 sbio->logical + sbio->page_count * PAGE_SIZE !=
2076 spage->logical ||
2077 sbio->dev != spage->dev) {
2078 scrub_submit(sctx);
2079 goto again;
2080 }
2081
2082 sbio->pagev[sbio->page_count] = spage;
2083 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
2084 if (ret != PAGE_SIZE) {
2085 if (sbio->page_count < 1) {
2086 bio_put(sbio->bio);
2087 sbio->bio = NULL;
2088 return -EIO;
2089 }
2090 scrub_submit(sctx);
2091 goto again;
2092 }
2093
2094 scrub_block_get(sblock); /* one for the page added to the bio */
2095 atomic_inc(&sblock->outstanding_pages);
2096 sbio->page_count++;
2097 if (sbio->page_count == sctx->pages_per_rd_bio)
2098 scrub_submit(sctx);
2099
2100 return 0;
2101 }
2102
2103 static void scrub_missing_raid56_end_io(struct bio *bio)
2104 {
2105 struct scrub_block *sblock = bio->bi_private;
2106 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
2107
2108 if (bio->bi_status)
2109 sblock->no_io_error_seen = 0;
2110
2111 bio_put(bio);
2112
2113 btrfs_queue_work(fs_info->scrub_workers, &sblock->work);
2114 }
2115
2116 static void scrub_missing_raid56_worker(struct btrfs_work *work)
2117 {
2118 struct scrub_block *sblock = container_of(work, struct scrub_block, work);
2119 struct scrub_ctx *sctx = sblock->sctx;
2120 struct btrfs_fs_info *fs_info = sctx->fs_info;
2121 u64 logical;
2122 struct btrfs_device *dev;
2123
2124 logical = sblock->pagev[0]->logical;
2125 dev = sblock->pagev[0]->dev;
2126
2127 if (sblock->no_io_error_seen)
2128 scrub_recheck_block_checksum(sblock);
2129
2130 if (!sblock->no_io_error_seen) {
2131 spin_lock(&sctx->stat_lock);
2132 sctx->stat.read_errors++;
2133 spin_unlock(&sctx->stat_lock);
2134 btrfs_err_rl_in_rcu(fs_info,
2135 "IO error rebuilding logical %llu for dev %s",
2136 logical, rcu_str_deref(dev->name));
2137 } else if (sblock->header_error || sblock->checksum_error) {
2138 spin_lock(&sctx->stat_lock);
2139 sctx->stat.uncorrectable_errors++;
2140 spin_unlock(&sctx->stat_lock);
2141 btrfs_err_rl_in_rcu(fs_info,
2142 "failed to rebuild valid logical %llu for dev %s",
2143 logical, rcu_str_deref(dev->name));
2144 } else {
2145 scrub_write_block_to_dev_replace(sblock);
2146 }
2147
2148 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2149 mutex_lock(&sctx->wr_lock);
2150 scrub_wr_submit(sctx);
2151 mutex_unlock(&sctx->wr_lock);
2152 }
2153
2154 scrub_block_put(sblock);
2155 scrub_pending_bio_dec(sctx);
2156 }
2157
2158 static void scrub_missing_raid56_pages(struct scrub_block *sblock)
2159 {
2160 struct scrub_ctx *sctx = sblock->sctx;
2161 struct btrfs_fs_info *fs_info = sctx->fs_info;
2162 u64 length = sblock->page_count * PAGE_SIZE;
2163 u64 logical = sblock->pagev[0]->logical;
2164 struct btrfs_bio *bbio = NULL;
2165 struct bio *bio;
2166 struct btrfs_raid_bio *rbio;
2167 int ret;
2168 int i;
2169
2170 btrfs_bio_counter_inc_blocked(fs_info);
2171 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
2172 &length, &bbio);
2173 if (ret || !bbio || !bbio->raid_map)
2174 goto bbio_out;
2175
2176 if (WARN_ON(!sctx->is_dev_replace ||
2177 !(bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK))) {
2178 /*
2179 * We shouldn't be scrubbing a missing device. Even for dev
2180 * replace, we should only get here for RAID 5/6. We either
2181 * managed to mount something with no mirrors remaining or
2182 * there's a bug in scrub_remap_extent()/btrfs_map_block().
2183 */
2184 goto bbio_out;
2185 }
2186
2187 bio = btrfs_io_bio_alloc(0);
2188 bio->bi_iter.bi_sector = logical >> 9;
2189 bio->bi_private = sblock;
2190 bio->bi_end_io = scrub_missing_raid56_end_io;
2191
2192 rbio = raid56_alloc_missing_rbio(fs_info, bio, bbio, length);
2193 if (!rbio)
2194 goto rbio_out;
2195
2196 for (i = 0; i < sblock->page_count; i++) {
2197 struct scrub_page *spage = sblock->pagev[i];
2198
2199 raid56_add_scrub_pages(rbio, spage->page, spage->logical);
2200 }
2201
2202 btrfs_init_work(&sblock->work, btrfs_scrub_helper,
2203 scrub_missing_raid56_worker, NULL, NULL);
2204 scrub_block_get(sblock);
2205 scrub_pending_bio_inc(sctx);
2206 raid56_submit_missing_rbio(rbio);
2207 return;
2208
2209 rbio_out:
2210 bio_put(bio);
2211 bbio_out:
2212 btrfs_bio_counter_dec(fs_info);
2213 btrfs_put_bbio(bbio);
2214 spin_lock(&sctx->stat_lock);
2215 sctx->stat.malloc_errors++;
2216 spin_unlock(&sctx->stat_lock);
2217 }
2218
2219 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
2220 u64 physical, struct btrfs_device *dev, u64 flags,
2221 u64 gen, int mirror_num, u8 *csum, int force,
2222 u64 physical_for_dev_replace)
2223 {
2224 struct scrub_block *sblock;
2225 int index;
2226
2227 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2228 if (!sblock) {
2229 spin_lock(&sctx->stat_lock);
2230 sctx->stat.malloc_errors++;
2231 spin_unlock(&sctx->stat_lock);
2232 return -ENOMEM;
2233 }
2234
2235 /* one ref inside this function, plus one for each page added to
2236 * a bio later on */
2237 refcount_set(&sblock->refs, 1);
2238 sblock->sctx = sctx;
2239 sblock->no_io_error_seen = 1;
2240
2241 for (index = 0; len > 0; index++) {
2242 struct scrub_page *spage;
2243 u64 l = min_t(u64, len, PAGE_SIZE);
2244
2245 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2246 if (!spage) {
2247 leave_nomem:
2248 spin_lock(&sctx->stat_lock);
2249 sctx->stat.malloc_errors++;
2250 spin_unlock(&sctx->stat_lock);
2251 scrub_block_put(sblock);
2252 return -ENOMEM;
2253 }
2254 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2255 scrub_page_get(spage);
2256 sblock->pagev[index] = spage;
2257 spage->sblock = sblock;
2258 spage->dev = dev;
2259 spage->flags = flags;
2260 spage->generation = gen;
2261 spage->logical = logical;
2262 spage->physical = physical;
2263 spage->physical_for_dev_replace = physical_for_dev_replace;
2264 spage->mirror_num = mirror_num;
2265 if (csum) {
2266 spage->have_csum = 1;
2267 memcpy(spage->csum, csum, sctx->csum_size);
2268 } else {
2269 spage->have_csum = 0;
2270 }
2271 sblock->page_count++;
2272 spage->page = alloc_page(GFP_KERNEL);
2273 if (!spage->page)
2274 goto leave_nomem;
2275 len -= l;
2276 logical += l;
2277 physical += l;
2278 physical_for_dev_replace += l;
2279 }
2280
2281 WARN_ON(sblock->page_count == 0);
2282 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2283 /*
2284 * This case should only be hit for RAID 5/6 device replace. See
2285 * the comment in scrub_missing_raid56_pages() for details.
2286 */
2287 scrub_missing_raid56_pages(sblock);
2288 } else {
2289 for (index = 0; index < sblock->page_count; index++) {
2290 struct scrub_page *spage = sblock->pagev[index];
2291 int ret;
2292
2293 ret = scrub_add_page_to_rd_bio(sctx, spage);
2294 if (ret) {
2295 scrub_block_put(sblock);
2296 return ret;
2297 }
2298 }
2299
2300 if (force)
2301 scrub_submit(sctx);
2302 }
2303
2304 /* last one frees, either here or in bio completion for last page */
2305 scrub_block_put(sblock);
2306 return 0;
2307 }
2308
2309 static void scrub_bio_end_io(struct bio *bio)
2310 {
2311 struct scrub_bio *sbio = bio->bi_private;
2312 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
2313
2314 sbio->status = bio->bi_status;
2315 sbio->bio = bio;
2316
2317 btrfs_queue_work(fs_info->scrub_workers, &sbio->work);
2318 }
2319
2320 static void scrub_bio_end_io_worker(struct btrfs_work *work)
2321 {
2322 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
2323 struct scrub_ctx *sctx = sbio->sctx;
2324 int i;
2325
2326 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO);
2327 if (sbio->status) {
2328 for (i = 0; i < sbio->page_count; i++) {
2329 struct scrub_page *spage = sbio->pagev[i];
2330
2331 spage->io_error = 1;
2332 spage->sblock->no_io_error_seen = 0;
2333 }
2334 }
2335
2336 /* now complete the scrub_block items that have all pages completed */
2337 for (i = 0; i < sbio->page_count; i++) {
2338 struct scrub_page *spage = sbio->pagev[i];
2339 struct scrub_block *sblock = spage->sblock;
2340
2341 if (atomic_dec_and_test(&sblock->outstanding_pages))
2342 scrub_block_complete(sblock);
2343 scrub_block_put(sblock);
2344 }
2345
2346 bio_put(sbio->bio);
2347 sbio->bio = NULL;
2348 spin_lock(&sctx->list_lock);
2349 sbio->next_free = sctx->first_free;
2350 sctx->first_free = sbio->index;
2351 spin_unlock(&sctx->list_lock);
2352
2353 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2354 mutex_lock(&sctx->wr_lock);
2355 scrub_wr_submit(sctx);
2356 mutex_unlock(&sctx->wr_lock);
2357 }
2358
2359 scrub_pending_bio_dec(sctx);
2360 }
2361
2362 static inline void __scrub_mark_bitmap(struct scrub_parity *sparity,
2363 unsigned long *bitmap,
2364 u64 start, u64 len)
2365 {
2366 u64 offset;
2367 u64 nsectors64;
2368 u32 nsectors;
2369 int sectorsize = sparity->sctx->fs_info->sectorsize;
2370
2371 if (len >= sparity->stripe_len) {
2372 bitmap_set(bitmap, 0, sparity->nsectors);
2373 return;
2374 }
2375
2376 start -= sparity->logic_start;
2377 start = div64_u64_rem(start, sparity->stripe_len, &offset);
2378 offset = div_u64(offset, sectorsize);
2379 nsectors64 = div_u64(len, sectorsize);
2380
2381 ASSERT(nsectors64 < UINT_MAX);
2382 nsectors = (u32)nsectors64;
2383
2384 if (offset + nsectors <= sparity->nsectors) {
2385 bitmap_set(bitmap, offset, nsectors);
2386 return;
2387 }
2388
2389 bitmap_set(bitmap, offset, sparity->nsectors - offset);
2390 bitmap_set(bitmap, 0, nsectors - (sparity->nsectors - offset));
2391 }
2392
2393 static inline void scrub_parity_mark_sectors_error(struct scrub_parity *sparity,
2394 u64 start, u64 len)
2395 {
2396 __scrub_mark_bitmap(sparity, sparity->ebitmap, start, len);
2397 }
2398
2399 static inline void scrub_parity_mark_sectors_data(struct scrub_parity *sparity,
2400 u64 start, u64 len)
2401 {
2402 __scrub_mark_bitmap(sparity, sparity->dbitmap, start, len);
2403 }
2404
2405 static void scrub_block_complete(struct scrub_block *sblock)
2406 {
2407 int corrupted = 0;
2408
2409 if (!sblock->no_io_error_seen) {
2410 corrupted = 1;
2411 scrub_handle_errored_block(sblock);
2412 } else {
2413 /*
2414 * if has checksum error, write via repair mechanism in
2415 * dev replace case, otherwise write here in dev replace
2416 * case.
2417 */
2418 corrupted = scrub_checksum(sblock);
2419 if (!corrupted && sblock->sctx->is_dev_replace)
2420 scrub_write_block_to_dev_replace(sblock);
2421 }
2422
2423 if (sblock->sparity && corrupted && !sblock->data_corrected) {
2424 u64 start = sblock->pagev[0]->logical;
2425 u64 end = sblock->pagev[sblock->page_count - 1]->logical +
2426 PAGE_SIZE;
2427
2428 scrub_parity_mark_sectors_error(sblock->sparity,
2429 start, end - start);
2430 }
2431 }
2432
2433 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum)
2434 {
2435 struct btrfs_ordered_sum *sum = NULL;
2436 unsigned long index;
2437 unsigned long num_sectors;
2438
2439 while (!list_empty(&sctx->csum_list)) {
2440 sum = list_first_entry(&sctx->csum_list,
2441 struct btrfs_ordered_sum, list);
2442 if (sum->bytenr > logical)
2443 return 0;
2444 if (sum->bytenr + sum->len > logical)
2445 break;
2446
2447 ++sctx->stat.csum_discards;
2448 list_del(&sum->list);
2449 kfree(sum);
2450 sum = NULL;
2451 }
2452 if (!sum)
2453 return 0;
2454
2455 index = div_u64(logical - sum->bytenr, sctx->fs_info->sectorsize);
2456 ASSERT(index < UINT_MAX);
2457
2458 num_sectors = sum->len / sctx->fs_info->sectorsize;
2459 memcpy(csum, sum->sums + index, sctx->csum_size);
2460 if (index == num_sectors - 1) {
2461 list_del(&sum->list);
2462 kfree(sum);
2463 }
2464 return 1;
2465 }
2466
2467 /* scrub extent tries to collect up to 64 kB for each bio */
2468 static int scrub_extent(struct scrub_ctx *sctx, struct map_lookup *map,
2469 u64 logical, u64 len,
2470 u64 physical, struct btrfs_device *dev, u64 flags,
2471 u64 gen, int mirror_num, u64 physical_for_dev_replace)
2472 {
2473 int ret;
2474 u8 csum[BTRFS_CSUM_SIZE];
2475 u32 blocksize;
2476
2477 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2478 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2479 blocksize = map->stripe_len;
2480 else
2481 blocksize = sctx->fs_info->sectorsize;
2482 spin_lock(&sctx->stat_lock);
2483 sctx->stat.data_extents_scrubbed++;
2484 sctx->stat.data_bytes_scrubbed += len;
2485 spin_unlock(&sctx->stat_lock);
2486 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2487 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2488 blocksize = map->stripe_len;
2489 else
2490 blocksize = sctx->fs_info->nodesize;
2491 spin_lock(&sctx->stat_lock);
2492 sctx->stat.tree_extents_scrubbed++;
2493 sctx->stat.tree_bytes_scrubbed += len;
2494 spin_unlock(&sctx->stat_lock);
2495 } else {
2496 blocksize = sctx->fs_info->sectorsize;
2497 WARN_ON(1);
2498 }
2499
2500 while (len) {
2501 u64 l = min_t(u64, len, blocksize);
2502 int have_csum = 0;
2503
2504 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2505 /* push csums to sbio */
2506 have_csum = scrub_find_csum(sctx, logical, csum);
2507 if (have_csum == 0)
2508 ++sctx->stat.no_csum;
2509 }
2510 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen,
2511 mirror_num, have_csum ? csum : NULL, 0,
2512 physical_for_dev_replace);
2513 if (ret)
2514 return ret;
2515 len -= l;
2516 logical += l;
2517 physical += l;
2518 physical_for_dev_replace += l;
2519 }
2520 return 0;
2521 }
2522
2523 static int scrub_pages_for_parity(struct scrub_parity *sparity,
2524 u64 logical, u64 len,
2525 u64 physical, struct btrfs_device *dev,
2526 u64 flags, u64 gen, int mirror_num, u8 *csum)
2527 {
2528 struct scrub_ctx *sctx = sparity->sctx;
2529 struct scrub_block *sblock;
2530 int index;
2531
2532 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2533 if (!sblock) {
2534 spin_lock(&sctx->stat_lock);
2535 sctx->stat.malloc_errors++;
2536 spin_unlock(&sctx->stat_lock);
2537 return -ENOMEM;
2538 }
2539
2540 /* one ref inside this function, plus one for each page added to
2541 * a bio later on */
2542 refcount_set(&sblock->refs, 1);
2543 sblock->sctx = sctx;
2544 sblock->no_io_error_seen = 1;
2545 sblock->sparity = sparity;
2546 scrub_parity_get(sparity);
2547
2548 for (index = 0; len > 0; index++) {
2549 struct scrub_page *spage;
2550 u64 l = min_t(u64, len, PAGE_SIZE);
2551
2552 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2553 if (!spage) {
2554 leave_nomem:
2555 spin_lock(&sctx->stat_lock);
2556 sctx->stat.malloc_errors++;
2557 spin_unlock(&sctx->stat_lock);
2558 scrub_block_put(sblock);
2559 return -ENOMEM;
2560 }
2561 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2562 /* For scrub block */
2563 scrub_page_get(spage);
2564 sblock->pagev[index] = spage;
2565 /* For scrub parity */
2566 scrub_page_get(spage);
2567 list_add_tail(&spage->list, &sparity->spages);
2568 spage->sblock = sblock;
2569 spage->dev = dev;
2570 spage->flags = flags;
2571 spage->generation = gen;
2572 spage->logical = logical;
2573 spage->physical = physical;
2574 spage->mirror_num = mirror_num;
2575 if (csum) {
2576 spage->have_csum = 1;
2577 memcpy(spage->csum, csum, sctx->csum_size);
2578 } else {
2579 spage->have_csum = 0;
2580 }
2581 sblock->page_count++;
2582 spage->page = alloc_page(GFP_KERNEL);
2583 if (!spage->page)
2584 goto leave_nomem;
2585 len -= l;
2586 logical += l;
2587 physical += l;
2588 }
2589
2590 WARN_ON(sblock->page_count == 0);
2591 for (index = 0; index < sblock->page_count; index++) {
2592 struct scrub_page *spage = sblock->pagev[index];
2593 int ret;
2594
2595 ret = scrub_add_page_to_rd_bio(sctx, spage);
2596 if (ret) {
2597 scrub_block_put(sblock);
2598 return ret;
2599 }
2600 }
2601
2602 /* last one frees, either here or in bio completion for last page */
2603 scrub_block_put(sblock);
2604 return 0;
2605 }
2606
2607 static int scrub_extent_for_parity(struct scrub_parity *sparity,
2608 u64 logical, u64 len,
2609 u64 physical, struct btrfs_device *dev,
2610 u64 flags, u64 gen, int mirror_num)
2611 {
2612 struct scrub_ctx *sctx = sparity->sctx;
2613 int ret;
2614 u8 csum[BTRFS_CSUM_SIZE];
2615 u32 blocksize;
2616
2617 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2618 scrub_parity_mark_sectors_error(sparity, logical, len);
2619 return 0;
2620 }
2621
2622 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2623 blocksize = sparity->stripe_len;
2624 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2625 blocksize = sparity->stripe_len;
2626 } else {
2627 blocksize = sctx->fs_info->sectorsize;
2628 WARN_ON(1);
2629 }
2630
2631 while (len) {
2632 u64 l = min_t(u64, len, blocksize);
2633 int have_csum = 0;
2634
2635 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2636 /* push csums to sbio */
2637 have_csum = scrub_find_csum(sctx, logical, csum);
2638 if (have_csum == 0)
2639 goto skip;
2640 }
2641 ret = scrub_pages_for_parity(sparity, logical, l, physical, dev,
2642 flags, gen, mirror_num,
2643 have_csum ? csum : NULL);
2644 if (ret)
2645 return ret;
2646 skip:
2647 len -= l;
2648 logical += l;
2649 physical += l;
2650 }
2651 return 0;
2652 }
2653
2654 /*
2655 * Given a physical address, this will calculate it's
2656 * logical offset. if this is a parity stripe, it will return
2657 * the most left data stripe's logical offset.
2658 *
2659 * return 0 if it is a data stripe, 1 means parity stripe.
2660 */
2661 static int get_raid56_logic_offset(u64 physical, int num,
2662 struct map_lookup *map, u64 *offset,
2663 u64 *stripe_start)
2664 {
2665 int i;
2666 int j = 0;
2667 u64 stripe_nr;
2668 u64 last_offset;
2669 u32 stripe_index;
2670 u32 rot;
2671
2672 last_offset = (physical - map->stripes[num].physical) *
2673 nr_data_stripes(map);
2674 if (stripe_start)
2675 *stripe_start = last_offset;
2676
2677 *offset = last_offset;
2678 for (i = 0; i < nr_data_stripes(map); i++) {
2679 *offset = last_offset + i * map->stripe_len;
2680
2681 stripe_nr = div64_u64(*offset, map->stripe_len);
2682 stripe_nr = div_u64(stripe_nr, nr_data_stripes(map));
2683
2684 /* Work out the disk rotation on this stripe-set */
2685 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);
2686 /* calculate which stripe this data locates */
2687 rot += i;
2688 stripe_index = rot % map->num_stripes;
2689 if (stripe_index == num)
2690 return 0;
2691 if (stripe_index < num)
2692 j++;
2693 }
2694 *offset = last_offset + j * map->stripe_len;
2695 return 1;
2696 }
2697
2698 static void scrub_free_parity(struct scrub_parity *sparity)
2699 {
2700 struct scrub_ctx *sctx = sparity->sctx;
2701 struct scrub_page *curr, *next;
2702 int nbits;
2703
2704 nbits = bitmap_weight(sparity->ebitmap, sparity->nsectors);
2705 if (nbits) {
2706 spin_lock(&sctx->stat_lock);
2707 sctx->stat.read_errors += nbits;
2708 sctx->stat.uncorrectable_errors += nbits;
2709 spin_unlock(&sctx->stat_lock);
2710 }
2711
2712 list_for_each_entry_safe(curr, next, &sparity->spages, list) {
2713 list_del_init(&curr->list);
2714 scrub_page_put(curr);
2715 }
2716
2717 kfree(sparity);
2718 }
2719
2720 static void scrub_parity_bio_endio_worker(struct btrfs_work *work)
2721 {
2722 struct scrub_parity *sparity = container_of(work, struct scrub_parity,
2723 work);
2724 struct scrub_ctx *sctx = sparity->sctx;
2725
2726 scrub_free_parity(sparity);
2727 scrub_pending_bio_dec(sctx);
2728 }
2729
2730 static void scrub_parity_bio_endio(struct bio *bio)
2731 {
2732 struct scrub_parity *sparity = (struct scrub_parity *)bio->bi_private;
2733 struct btrfs_fs_info *fs_info = sparity->sctx->fs_info;
2734
2735 if (bio->bi_status)
2736 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2737 sparity->nsectors);
2738
2739 bio_put(bio);
2740
2741 btrfs_init_work(&sparity->work, btrfs_scrubparity_helper,
2742 scrub_parity_bio_endio_worker, NULL, NULL);
2743 btrfs_queue_work(fs_info->scrub_parity_workers, &sparity->work);
2744 }
2745
2746 static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
2747 {
2748 struct scrub_ctx *sctx = sparity->sctx;
2749 struct btrfs_fs_info *fs_info = sctx->fs_info;
2750 struct bio *bio;
2751 struct btrfs_raid_bio *rbio;
2752 struct btrfs_bio *bbio = NULL;
2753 u64 length;
2754 int ret;
2755
2756 if (!bitmap_andnot(sparity->dbitmap, sparity->dbitmap, sparity->ebitmap,
2757 sparity->nsectors))
2758 goto out;
2759
2760 length = sparity->logic_end - sparity->logic_start;
2761
2762 btrfs_bio_counter_inc_blocked(fs_info);
2763 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start,
2764 &length, &bbio);
2765 if (ret || !bbio || !bbio->raid_map)
2766 goto bbio_out;
2767
2768 bio = btrfs_io_bio_alloc(0);
2769 bio->bi_iter.bi_sector = sparity->logic_start >> 9;
2770 bio->bi_private = sparity;
2771 bio->bi_end_io = scrub_parity_bio_endio;
2772
2773 rbio = raid56_parity_alloc_scrub_rbio(fs_info, bio, bbio,
2774 length, sparity->scrub_dev,
2775 sparity->dbitmap,
2776 sparity->nsectors);
2777 if (!rbio)
2778 goto rbio_out;
2779
2780 scrub_pending_bio_inc(sctx);
2781 raid56_parity_submit_scrub_rbio(rbio);
2782 return;
2783
2784 rbio_out:
2785 bio_put(bio);
2786 bbio_out:
2787 btrfs_bio_counter_dec(fs_info);
2788 btrfs_put_bbio(bbio);
2789 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2790 sparity->nsectors);
2791 spin_lock(&sctx->stat_lock);
2792 sctx->stat.malloc_errors++;
2793 spin_unlock(&sctx->stat_lock);
2794 out:
2795 scrub_free_parity(sparity);
2796 }
2797
2798 static inline int scrub_calc_parity_bitmap_len(int nsectors)
2799 {
2800 return DIV_ROUND_UP(nsectors, BITS_PER_LONG) * sizeof(long);
2801 }
2802
2803 static void scrub_parity_get(struct scrub_parity *sparity)
2804 {
2805 refcount_inc(&sparity->refs);
2806 }
2807
2808 static void scrub_parity_put(struct scrub_parity *sparity)
2809 {
2810 if (!refcount_dec_and_test(&sparity->refs))
2811 return;
2812
2813 scrub_parity_check_and_repair(sparity);
2814 }
2815
2816 static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
2817 struct map_lookup *map,
2818 struct btrfs_device *sdev,
2819 struct btrfs_path *path,
2820 u64 logic_start,
2821 u64 logic_end)
2822 {
2823 struct btrfs_fs_info *fs_info = sctx->fs_info;
2824 struct btrfs_root *root = fs_info->extent_root;
2825 struct btrfs_root *csum_root = fs_info->csum_root;
2826 struct btrfs_extent_item *extent;
2827 struct btrfs_bio *bbio = NULL;
2828 u64 flags;
2829 int ret;
2830 int slot;
2831 struct extent_buffer *l;
2832 struct btrfs_key key;
2833 u64 generation;
2834 u64 extent_logical;
2835 u64 extent_physical;
2836 u64 extent_len;
2837 u64 mapped_length;
2838 struct btrfs_device *extent_dev;
2839 struct scrub_parity *sparity;
2840 int nsectors;
2841 int bitmap_len;
2842 int extent_mirror_num;
2843 int stop_loop = 0;
2844
2845 nsectors = div_u64(map->stripe_len, fs_info->sectorsize);
2846 bitmap_len = scrub_calc_parity_bitmap_len(nsectors);
2847 sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len,
2848 GFP_NOFS);
2849 if (!sparity) {
2850 spin_lock(&sctx->stat_lock);
2851 sctx->stat.malloc_errors++;
2852 spin_unlock(&sctx->stat_lock);
2853 return -ENOMEM;
2854 }
2855
2856 sparity->stripe_len = map->stripe_len;
2857 sparity->nsectors = nsectors;
2858 sparity->sctx = sctx;
2859 sparity->scrub_dev = sdev;
2860 sparity->logic_start = logic_start;
2861 sparity->logic_end = logic_end;
2862 refcount_set(&sparity->refs, 1);
2863 INIT_LIST_HEAD(&sparity->spages);
2864 sparity->dbitmap = sparity->bitmap;
2865 sparity->ebitmap = (void *)sparity->bitmap + bitmap_len;
2866
2867 ret = 0;
2868 while (logic_start < logic_end) {
2869 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2870 key.type = BTRFS_METADATA_ITEM_KEY;
2871 else
2872 key.type = BTRFS_EXTENT_ITEM_KEY;
2873 key.objectid = logic_start;
2874 key.offset = (u64)-1;
2875
2876 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2877 if (ret < 0)
2878 goto out;
2879
2880 if (ret > 0) {
2881 ret = btrfs_previous_extent_item(root, path, 0);
2882 if (ret < 0)
2883 goto out;
2884 if (ret > 0) {
2885 btrfs_release_path(path);
2886 ret = btrfs_search_slot(NULL, root, &key,
2887 path, 0, 0);
2888 if (ret < 0)
2889 goto out;
2890 }
2891 }
2892
2893 stop_loop = 0;
2894 while (1) {
2895 u64 bytes;
2896
2897 l = path->nodes[0];
2898 slot = path->slots[0];
2899 if (slot >= btrfs_header_nritems(l)) {
2900 ret = btrfs_next_leaf(root, path);
2901 if (ret == 0)
2902 continue;
2903 if (ret < 0)
2904 goto out;
2905
2906 stop_loop = 1;
2907 break;
2908 }
2909 btrfs_item_key_to_cpu(l, &key, slot);
2910
2911 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
2912 key.type != BTRFS_METADATA_ITEM_KEY)
2913 goto next;
2914
2915 if (key.type == BTRFS_METADATA_ITEM_KEY)
2916 bytes = fs_info->nodesize;
2917 else
2918 bytes = key.offset;
2919
2920 if (key.objectid + bytes <= logic_start)
2921 goto next;
2922
2923 if (key.objectid >= logic_end) {
2924 stop_loop = 1;
2925 break;
2926 }
2927
2928 while (key.objectid >= logic_start + map->stripe_len)
2929 logic_start += map->stripe_len;
2930
2931 extent = btrfs_item_ptr(l, slot,
2932 struct btrfs_extent_item);
2933 flags = btrfs_extent_flags(l, extent);
2934 generation = btrfs_extent_generation(l, extent);
2935
2936 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
2937 (key.objectid < logic_start ||
2938 key.objectid + bytes >
2939 logic_start + map->stripe_len)) {
2940 btrfs_err(fs_info,
2941 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
2942 key.objectid, logic_start);
2943 spin_lock(&sctx->stat_lock);
2944 sctx->stat.uncorrectable_errors++;
2945 spin_unlock(&sctx->stat_lock);
2946 goto next;
2947 }
2948 again:
2949 extent_logical = key.objectid;
2950 extent_len = bytes;
2951
2952 if (extent_logical < logic_start) {
2953 extent_len -= logic_start - extent_logical;
2954 extent_logical = logic_start;
2955 }
2956
2957 if (extent_logical + extent_len >
2958 logic_start + map->stripe_len)
2959 extent_len = logic_start + map->stripe_len -
2960 extent_logical;
2961
2962 scrub_parity_mark_sectors_data(sparity, extent_logical,
2963 extent_len);
2964
2965 mapped_length = extent_len;
2966 bbio = NULL;
2967 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ,
2968 extent_logical, &mapped_length, &bbio,
2969 0);
2970 if (!ret) {
2971 if (!bbio || mapped_length < extent_len)
2972 ret = -EIO;
2973 }
2974 if (ret) {
2975 btrfs_put_bbio(bbio);
2976 goto out;
2977 }
2978 extent_physical = bbio->stripes[0].physical;
2979 extent_mirror_num = bbio->mirror_num;
2980 extent_dev = bbio->stripes[0].dev;
2981 btrfs_put_bbio(bbio);
2982
2983 ret = btrfs_lookup_csums_range(csum_root,
2984 extent_logical,
2985 extent_logical + extent_len - 1,
2986 &sctx->csum_list, 1);
2987 if (ret)
2988 goto out;
2989
2990 ret = scrub_extent_for_parity(sparity, extent_logical,
2991 extent_len,
2992 extent_physical,
2993 extent_dev, flags,
2994 generation,
2995 extent_mirror_num);
2996
2997 scrub_free_csums(sctx);
2998
2999 if (ret)
3000 goto out;
3001
3002 if (extent_logical + extent_len <
3003 key.objectid + bytes) {
3004 logic_start += map->stripe_len;
3005
3006 if (logic_start >= logic_end) {
3007 stop_loop = 1;
3008 break;
3009 }
3010
3011 if (logic_start < key.objectid + bytes) {
3012 cond_resched();
3013 goto again;
3014 }
3015 }
3016 next:
3017 path->slots[0]++;
3018 }
3019
3020 btrfs_release_path(path);
3021
3022 if (stop_loop)
3023 break;
3024
3025 logic_start += map->stripe_len;
3026 }
3027 out:
3028 if (ret < 0)
3029 scrub_parity_mark_sectors_error(sparity, logic_start,
3030 logic_end - logic_start);
3031 scrub_parity_put(sparity);
3032 scrub_submit(sctx);
3033 mutex_lock(&sctx->wr_lock);
3034 scrub_wr_submit(sctx);
3035 mutex_unlock(&sctx->wr_lock);
3036
3037 btrfs_release_path(path);
3038 return ret < 0 ? ret : 0;
3039 }
3040
3041 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
3042 struct map_lookup *map,
3043 struct btrfs_device *scrub_dev,
3044 int num, u64 base, u64 length)
3045 {
3046 struct btrfs_path *path, *ppath;
3047 struct btrfs_fs_info *fs_info = sctx->fs_info;
3048 struct btrfs_root *root = fs_info->extent_root;
3049 struct btrfs_root *csum_root = fs_info->csum_root;
3050 struct btrfs_extent_item *extent;
3051 struct blk_plug plug;
3052 u64 flags;
3053 int ret;
3054 int slot;
3055 u64 nstripes;
3056 struct extent_buffer *l;
3057 u64 physical;
3058 u64 logical;
3059 u64 logic_end;
3060 u64 physical_end;
3061 u64 generation;
3062 int mirror_num;
3063 struct reada_control *reada1;
3064 struct reada_control *reada2;
3065 struct btrfs_key key;
3066 struct btrfs_key key_end;
3067 u64 increment = map->stripe_len;
3068 u64 offset;
3069 u64 extent_logical;
3070 u64 extent_physical;
3071 u64 extent_len;
3072 u64 stripe_logical;
3073 u64 stripe_end;
3074 struct btrfs_device *extent_dev;
3075 int extent_mirror_num;
3076 int stop_loop = 0;
3077
3078 physical = map->stripes[num].physical;
3079 offset = 0;
3080 nstripes = div64_u64(length, map->stripe_len);
3081 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3082 offset = map->stripe_len * num;
3083 increment = map->stripe_len * map->num_stripes;
3084 mirror_num = 1;
3085 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3086 int factor = map->num_stripes / map->sub_stripes;
3087 offset = map->stripe_len * (num / map->sub_stripes);
3088 increment = map->stripe_len * factor;
3089 mirror_num = num % map->sub_stripes + 1;
3090 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
3091 increment = map->stripe_len;
3092 mirror_num = num % map->num_stripes + 1;
3093 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
3094 increment = map->stripe_len;
3095 mirror_num = num % map->num_stripes + 1;
3096 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3097 get_raid56_logic_offset(physical, num, map, &offset, NULL);
3098 increment = map->stripe_len * nr_data_stripes(map);
3099 mirror_num = 1;
3100 } else {
3101 increment = map->stripe_len;
3102 mirror_num = 1;
3103 }
3104
3105 path = btrfs_alloc_path();
3106 if (!path)
3107 return -ENOMEM;
3108
3109 ppath = btrfs_alloc_path();
3110 if (!ppath) {
3111 btrfs_free_path(path);
3112 return -ENOMEM;
3113 }
3114
3115 /*
3116 * work on commit root. The related disk blocks are static as
3117 * long as COW is applied. This means, it is save to rewrite
3118 * them to repair disk errors without any race conditions
3119 */
3120 path->search_commit_root = 1;
3121 path->skip_locking = 1;
3122
3123 ppath->search_commit_root = 1;
3124 ppath->skip_locking = 1;
3125 /*
3126 * trigger the readahead for extent tree csum tree and wait for
3127 * completion. During readahead, the scrub is officially paused
3128 * to not hold off transaction commits
3129 */
3130 logical = base + offset;
3131 physical_end = physical + nstripes * map->stripe_len;
3132 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3133 get_raid56_logic_offset(physical_end, num,
3134 map, &logic_end, NULL);
3135 logic_end += base;
3136 } else {
3137 logic_end = logical + increment * nstripes;
3138 }
3139 wait_event(sctx->list_wait,
3140 atomic_read(&sctx->bios_in_flight) == 0);
3141 scrub_blocked_if_needed(fs_info);
3142
3143 /* FIXME it might be better to start readahead at commit root */
3144 key.objectid = logical;
3145 key.type = BTRFS_EXTENT_ITEM_KEY;
3146 key.offset = (u64)0;
3147 key_end.objectid = logic_end;
3148 key_end.type = BTRFS_METADATA_ITEM_KEY;
3149 key_end.offset = (u64)-1;
3150 reada1 = btrfs_reada_add(root, &key, &key_end);
3151
3152 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3153 key.type = BTRFS_EXTENT_CSUM_KEY;
3154 key.offset = logical;
3155 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3156 key_end.type = BTRFS_EXTENT_CSUM_KEY;
3157 key_end.offset = logic_end;
3158 reada2 = btrfs_reada_add(csum_root, &key, &key_end);
3159
3160 if (!IS_ERR(reada1))
3161 btrfs_reada_wait(reada1);
3162 if (!IS_ERR(reada2))
3163 btrfs_reada_wait(reada2);
3164
3165
3166 /*
3167 * collect all data csums for the stripe to avoid seeking during
3168 * the scrub. This might currently (crc32) end up to be about 1MB
3169 */
3170 blk_start_plug(&plug);
3171
3172 /*
3173 * now find all extents for each stripe and scrub them
3174 */
3175 ret = 0;
3176 while (physical < physical_end) {
3177 /*
3178 * canceled?
3179 */
3180 if (atomic_read(&fs_info->scrub_cancel_req) ||
3181 atomic_read(&sctx->cancel_req)) {
3182 ret = -ECANCELED;
3183 goto out;
3184 }
3185 /*
3186 * check to see if we have to pause
3187 */
3188 if (atomic_read(&fs_info->scrub_pause_req)) {
3189 /* push queued extents */
3190 sctx->flush_all_writes = true;
3191 scrub_submit(sctx);
3192 mutex_lock(&sctx->wr_lock);
3193 scrub_wr_submit(sctx);
3194 mutex_unlock(&sctx->wr_lock);
3195 wait_event(sctx->list_wait,
3196 atomic_read(&sctx->bios_in_flight) == 0);
3197 sctx->flush_all_writes = false;
3198 scrub_blocked_if_needed(fs_info);
3199 }
3200
3201 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3202 ret = get_raid56_logic_offset(physical, num, map,
3203 &logical,
3204 &stripe_logical);
3205 logical += base;
3206 if (ret) {
3207 /* it is parity strip */
3208 stripe_logical += base;
3209 stripe_end = stripe_logical + increment;
3210 ret = scrub_raid56_parity(sctx, map, scrub_dev,
3211 ppath, stripe_logical,
3212 stripe_end);
3213 if (ret)
3214 goto out;
3215 goto skip;
3216 }
3217 }
3218
3219 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
3220 key.type = BTRFS_METADATA_ITEM_KEY;
3221 else
3222 key.type = BTRFS_EXTENT_ITEM_KEY;
3223 key.objectid = logical;
3224 key.offset = (u64)-1;
3225
3226 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3227 if (ret < 0)
3228 goto out;
3229
3230 if (ret > 0) {
3231 ret = btrfs_previous_extent_item(root, path, 0);
3232 if (ret < 0)
3233 goto out;
3234 if (ret > 0) {
3235 /* there's no smaller item, so stick with the
3236 * larger one */
3237 btrfs_release_path(path);
3238 ret = btrfs_search_slot(NULL, root, &key,
3239 path, 0, 0);
3240 if (ret < 0)
3241 goto out;
3242 }
3243 }
3244
3245 stop_loop = 0;
3246 while (1) {
3247 u64 bytes;
3248
3249 l = path->nodes[0];
3250 slot = path->slots[0];
3251 if (slot >= btrfs_header_nritems(l)) {
3252 ret = btrfs_next_leaf(root, path);
3253 if (ret == 0)
3254 continue;
3255 if (ret < 0)
3256 goto out;
3257
3258 stop_loop = 1;
3259 break;
3260 }
3261 btrfs_item_key_to_cpu(l, &key, slot);
3262
3263 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
3264 key.type != BTRFS_METADATA_ITEM_KEY)
3265 goto next;
3266
3267 if (key.type == BTRFS_METADATA_ITEM_KEY)
3268 bytes = fs_info->nodesize;
3269 else
3270 bytes = key.offset;
3271
3272 if (key.objectid + bytes <= logical)
3273 goto next;
3274
3275 if (key.objectid >= logical + map->stripe_len) {
3276 /* out of this device extent */
3277 if (key.objectid >= logic_end)
3278 stop_loop = 1;
3279 break;
3280 }
3281
3282 extent = btrfs_item_ptr(l, slot,
3283 struct btrfs_extent_item);
3284 flags = btrfs_extent_flags(l, extent);
3285 generation = btrfs_extent_generation(l, extent);
3286
3287 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
3288 (key.objectid < logical ||
3289 key.objectid + bytes >
3290 logical + map->stripe_len)) {
3291 btrfs_err(fs_info,
3292 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
3293 key.objectid, logical);
3294 spin_lock(&sctx->stat_lock);
3295 sctx->stat.uncorrectable_errors++;
3296 spin_unlock(&sctx->stat_lock);
3297 goto next;
3298 }
3299
3300 again:
3301 extent_logical = key.objectid;
3302 extent_len = bytes;
3303
3304 /*
3305 * trim extent to this stripe
3306 */
3307 if (extent_logical < logical) {
3308 extent_len -= logical - extent_logical;
3309 extent_logical = logical;
3310 }
3311 if (extent_logical + extent_len >
3312 logical + map->stripe_len) {
3313 extent_len = logical + map->stripe_len -
3314 extent_logical;
3315 }
3316
3317 extent_physical = extent_logical - logical + physical;
3318 extent_dev = scrub_dev;
3319 extent_mirror_num = mirror_num;
3320 if (sctx->is_dev_replace)
3321 scrub_remap_extent(fs_info, extent_logical,
3322 extent_len, &extent_physical,
3323 &extent_dev,
3324 &extent_mirror_num);
3325
3326 ret = btrfs_lookup_csums_range(csum_root,
3327 extent_logical,
3328 extent_logical +
3329 extent_len - 1,
3330 &sctx->csum_list, 1);
3331 if (ret)
3332 goto out;
3333
3334 ret = scrub_extent(sctx, map, extent_logical, extent_len,
3335 extent_physical, extent_dev, flags,
3336 generation, extent_mirror_num,
3337 extent_logical - logical + physical);
3338
3339 scrub_free_csums(sctx);
3340
3341 if (ret)
3342 goto out;
3343
3344 if (extent_logical + extent_len <
3345 key.objectid + bytes) {
3346 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3347 /*
3348 * loop until we find next data stripe
3349 * or we have finished all stripes.
3350 */
3351 loop:
3352 physical += map->stripe_len;
3353 ret = get_raid56_logic_offset(physical,
3354 num, map, &logical,
3355 &stripe_logical);
3356 logical += base;
3357
3358 if (ret && physical < physical_end) {
3359 stripe_logical += base;
3360 stripe_end = stripe_logical +
3361 increment;
3362 ret = scrub_raid56_parity(sctx,
3363 map, scrub_dev, ppath,
3364 stripe_logical,
3365 stripe_end);
3366 if (ret)
3367 goto out;
3368 goto loop;
3369 }
3370 } else {
3371 physical += map->stripe_len;
3372 logical += increment;
3373 }
3374 if (logical < key.objectid + bytes) {
3375 cond_resched();
3376 goto again;
3377 }
3378
3379 if (physical >= physical_end) {
3380 stop_loop = 1;
3381 break;
3382 }
3383 }
3384 next:
3385 path->slots[0]++;
3386 }
3387 btrfs_release_path(path);
3388 skip:
3389 logical += increment;
3390 physical += map->stripe_len;
3391 spin_lock(&sctx->stat_lock);
3392 if (stop_loop)
3393 sctx->stat.last_physical = map->stripes[num].physical +
3394 length;
3395 else
3396 sctx->stat.last_physical = physical;
3397 spin_unlock(&sctx->stat_lock);
3398 if (stop_loop)
3399 break;
3400 }
3401 out:
3402 /* push queued extents */
3403 scrub_submit(sctx);
3404 mutex_lock(&sctx->wr_lock);
3405 scrub_wr_submit(sctx);
3406 mutex_unlock(&sctx->wr_lock);
3407
3408 blk_finish_plug(&plug);
3409 btrfs_free_path(path);
3410 btrfs_free_path(ppath);
3411 return ret < 0 ? ret : 0;
3412 }
3413
3414 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
3415 struct btrfs_device *scrub_dev,
3416 u64 chunk_offset, u64 length,
3417 u64 dev_offset,
3418 struct btrfs_block_group_cache *cache)
3419 {
3420 struct btrfs_fs_info *fs_info = sctx->fs_info;
3421 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
3422 struct map_lookup *map;
3423 struct extent_map *em;
3424 int i;
3425 int ret = 0;
3426
3427 read_lock(&map_tree->map_tree.lock);
3428 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
3429 read_unlock(&map_tree->map_tree.lock);
3430
3431 if (!em) {
3432 /*
3433 * Might have been an unused block group deleted by the cleaner
3434 * kthread or relocation.
3435 */
3436 spin_lock(&cache->lock);
3437 if (!cache->removed)
3438 ret = -EINVAL;
3439 spin_unlock(&cache->lock);
3440
3441 return ret;
3442 }
3443
3444 map = em->map_lookup;
3445 if (em->start != chunk_offset)
3446 goto out;
3447
3448 if (em->len < length)
3449 goto out;
3450
3451 for (i = 0; i < map->num_stripes; ++i) {
3452 if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
3453 map->stripes[i].physical == dev_offset) {
3454 ret = scrub_stripe(sctx, map, scrub_dev, i,
3455 chunk_offset, length);
3456 if (ret)
3457 goto out;
3458 }
3459 }
3460 out:
3461 free_extent_map(em);
3462
3463 return ret;
3464 }
3465
3466 static noinline_for_stack
3467 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
3468 struct btrfs_device *scrub_dev, u64 start, u64 end)
3469 {
3470 struct btrfs_dev_extent *dev_extent = NULL;
3471 struct btrfs_path *path;
3472 struct btrfs_fs_info *fs_info = sctx->fs_info;
3473 struct btrfs_root *root = fs_info->dev_root;
3474 u64 length;
3475 u64 chunk_offset;
3476 int ret = 0;
3477 int ro_set;
3478 int slot;
3479 struct extent_buffer *l;
3480 struct btrfs_key key;
3481 struct btrfs_key found_key;
3482 struct btrfs_block_group_cache *cache;
3483 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
3484
3485 path = btrfs_alloc_path();
3486 if (!path)
3487 return -ENOMEM;
3488
3489 path->reada = READA_FORWARD;
3490 path->search_commit_root = 1;
3491 path->skip_locking = 1;
3492
3493 key.objectid = scrub_dev->devid;
3494 key.offset = 0ull;
3495 key.type = BTRFS_DEV_EXTENT_KEY;
3496
3497 while (1) {
3498 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3499 if (ret < 0)
3500 break;
3501 if (ret > 0) {
3502 if (path->slots[0] >=
3503 btrfs_header_nritems(path->nodes[0])) {
3504 ret = btrfs_next_leaf(root, path);
3505 if (ret < 0)
3506 break;
3507 if (ret > 0) {
3508 ret = 0;
3509 break;
3510 }
3511 } else {
3512 ret = 0;
3513 }
3514 }
3515
3516 l = path->nodes[0];
3517 slot = path->slots[0];
3518
3519 btrfs_item_key_to_cpu(l, &found_key, slot);
3520
3521 if (found_key.objectid != scrub_dev->devid)
3522 break;
3523
3524 if (found_key.type != BTRFS_DEV_EXTENT_KEY)
3525 break;
3526
3527 if (found_key.offset >= end)
3528 break;
3529
3530 if (found_key.offset < key.offset)
3531 break;
3532
3533 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
3534 length = btrfs_dev_extent_length(l, dev_extent);
3535
3536 if (found_key.offset + length <= start)
3537 goto skip;
3538
3539 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3540
3541 /*
3542 * get a reference on the corresponding block group to prevent
3543 * the chunk from going away while we scrub it
3544 */
3545 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3546
3547 /* some chunks are removed but not committed to disk yet,
3548 * continue scrubbing */
3549 if (!cache)
3550 goto skip;
3551
3552 /*
3553 * we need call btrfs_inc_block_group_ro() with scrubs_paused,
3554 * to avoid deadlock caused by:
3555 * btrfs_inc_block_group_ro()
3556 * -> btrfs_wait_for_commit()
3557 * -> btrfs_commit_transaction()
3558 * -> btrfs_scrub_pause()
3559 */
3560 scrub_pause_on(fs_info);
3561 ret = btrfs_inc_block_group_ro(cache);
3562 if (!ret && sctx->is_dev_replace) {
3563 /*
3564 * If we are doing a device replace wait for any tasks
3565 * that started dellaloc right before we set the block
3566 * group to RO mode, as they might have just allocated
3567 * an extent from it or decided they could do a nocow
3568 * write. And if any such tasks did that, wait for their
3569 * ordered extents to complete and then commit the
3570 * current transaction, so that we can later see the new
3571 * extent items in the extent tree - the ordered extents
3572 * create delayed data references (for cow writes) when
3573 * they complete, which will be run and insert the
3574 * corresponding extent items into the extent tree when
3575 * we commit the transaction they used when running
3576 * inode.c:btrfs_finish_ordered_io(). We later use
3577 * the commit root of the extent tree to find extents
3578 * to copy from the srcdev into the tgtdev, and we don't
3579 * want to miss any new extents.
3580 */
3581 btrfs_wait_block_group_reservations(cache);
3582 btrfs_wait_nocow_writers(cache);
3583 ret = btrfs_wait_ordered_roots(fs_info, U64_MAX,
3584 cache->key.objectid,
3585 cache->key.offset);
3586 if (ret > 0) {
3587 struct btrfs_trans_handle *trans;
3588
3589 trans = btrfs_join_transaction(root);
3590 if (IS_ERR(trans))
3591 ret = PTR_ERR(trans);
3592 else
3593 ret = btrfs_commit_transaction(trans);
3594 if (ret) {
3595 scrub_pause_off(fs_info);
3596 btrfs_put_block_group(cache);
3597 break;
3598 }
3599 }
3600 }
3601 scrub_pause_off(fs_info);
3602
3603 if (ret == 0) {
3604 ro_set = 1;
3605 } else if (ret == -ENOSPC) {
3606 /*
3607 * btrfs_inc_block_group_ro return -ENOSPC when it
3608 * failed in creating new chunk for metadata.
3609 * It is not a problem for scrub/replace, because
3610 * metadata are always cowed, and our scrub paused
3611 * commit_transactions.
3612 */
3613 ro_set = 0;
3614 } else {
3615 btrfs_warn(fs_info,
3616 "failed setting block group ro: %d", ret);
3617 btrfs_put_block_group(cache);
3618 break;
3619 }
3620
3621 btrfs_dev_replace_write_lock(&fs_info->dev_replace);
3622 dev_replace->cursor_right = found_key.offset + length;
3623 dev_replace->cursor_left = found_key.offset;
3624 dev_replace->item_needs_writeback = 1;
3625 btrfs_dev_replace_write_unlock(&fs_info->dev_replace);
3626 ret = scrub_chunk(sctx, scrub_dev, chunk_offset, length,
3627 found_key.offset, cache);
3628
3629 /*
3630 * flush, submit all pending read and write bios, afterwards
3631 * wait for them.
3632 * Note that in the dev replace case, a read request causes
3633 * write requests that are submitted in the read completion
3634 * worker. Therefore in the current situation, it is required
3635 * that all write requests are flushed, so that all read and
3636 * write requests are really completed when bios_in_flight
3637 * changes to 0.
3638 */
3639 sctx->flush_all_writes = true;
3640 scrub_submit(sctx);
3641 mutex_lock(&sctx->wr_lock);
3642 scrub_wr_submit(sctx);
3643 mutex_unlock(&sctx->wr_lock);
3644
3645 wait_event(sctx->list_wait,
3646 atomic_read(&sctx->bios_in_flight) == 0);
3647
3648 scrub_pause_on(fs_info);
3649
3650 /*
3651 * must be called before we decrease @scrub_paused.
3652 * make sure we don't block transaction commit while
3653 * we are waiting pending workers finished.
3654 */
3655 wait_event(sctx->list_wait,
3656 atomic_read(&sctx->workers_pending) == 0);
3657 sctx->flush_all_writes = false;
3658
3659 scrub_pause_off(fs_info);
3660
3661 btrfs_dev_replace_write_lock(&fs_info->dev_replace);
3662 dev_replace->cursor_left = dev_replace->cursor_right;
3663 dev_replace->item_needs_writeback = 1;
3664 btrfs_dev_replace_write_unlock(&fs_info->dev_replace);
3665
3666 if (ro_set)
3667 btrfs_dec_block_group_ro(cache);
3668
3669 /*
3670 * We might have prevented the cleaner kthread from deleting
3671 * this block group if it was already unused because we raced
3672 * and set it to RO mode first. So add it back to the unused
3673 * list, otherwise it might not ever be deleted unless a manual
3674 * balance is triggered or it becomes used and unused again.
3675 */
3676 spin_lock(&cache->lock);
3677 if (!cache->removed && !cache->ro && cache->reserved == 0 &&
3678 btrfs_block_group_used(&cache->item) == 0) {
3679 spin_unlock(&cache->lock);
3680 btrfs_mark_bg_unused(cache);
3681 } else {
3682 spin_unlock(&cache->lock);
3683 }
3684
3685 btrfs_put_block_group(cache);
3686 if (ret)
3687 break;
3688 if (sctx->is_dev_replace &&
3689 atomic64_read(&dev_replace->num_write_errors) > 0) {
3690 ret = -EIO;
3691 break;
3692 }
3693 if (sctx->stat.malloc_errors > 0) {
3694 ret = -ENOMEM;
3695 break;
3696 }
3697 skip:
3698 key.offset = found_key.offset + length;
3699 btrfs_release_path(path);
3700 }
3701
3702 btrfs_free_path(path);
3703
3704 return ret;
3705 }
3706
3707 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
3708 struct btrfs_device *scrub_dev)
3709 {
3710 int i;
3711 u64 bytenr;
3712 u64 gen;
3713 int ret;
3714 struct btrfs_fs_info *fs_info = sctx->fs_info;
3715
3716 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3717 return -EIO;
3718
3719 /* Seed devices of a new filesystem has their own generation. */
3720 if (scrub_dev->fs_devices != fs_info->fs_devices)
3721 gen = scrub_dev->generation;
3722 else
3723 gen = fs_info->last_trans_committed;
3724
3725 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
3726 bytenr = btrfs_sb_offset(i);
3727 if (bytenr + BTRFS_SUPER_INFO_SIZE >
3728 scrub_dev->commit_total_bytes)
3729 break;
3730
3731 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
3732 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
3733 NULL, 1, bytenr);
3734 if (ret)
3735 return ret;
3736 }
3737 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3738
3739 return 0;
3740 }
3741
3742 /*
3743 * get a reference count on fs_info->scrub_workers. start worker if necessary
3744 */
3745 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
3746 int is_dev_replace)
3747 {
3748 unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND;
3749 int max_active = fs_info->thread_pool_size;
3750
3751 if (fs_info->scrub_workers_refcnt == 0) {
3752 fs_info->scrub_workers = btrfs_alloc_workqueue(fs_info, "scrub",
3753 flags, is_dev_replace ? 1 : max_active, 4);
3754 if (!fs_info->scrub_workers)
3755 goto fail_scrub_workers;
3756
3757 fs_info->scrub_wr_completion_workers =
3758 btrfs_alloc_workqueue(fs_info, "scrubwrc", flags,
3759 max_active, 2);
3760 if (!fs_info->scrub_wr_completion_workers)
3761 goto fail_scrub_wr_completion_workers;
3762
3763 fs_info->scrub_parity_workers =
3764 btrfs_alloc_workqueue(fs_info, "scrubparity", flags,
3765 max_active, 2);
3766 if (!fs_info->scrub_parity_workers)
3767 goto fail_scrub_parity_workers;
3768 }
3769 ++fs_info->scrub_workers_refcnt;
3770 return 0;
3771
3772 fail_scrub_parity_workers:
3773 btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers);
3774 fail_scrub_wr_completion_workers:
3775 btrfs_destroy_workqueue(fs_info->scrub_workers);
3776 fail_scrub_workers:
3777 return -ENOMEM;
3778 }
3779
3780 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
3781 u64 end, struct btrfs_scrub_progress *progress,
3782 int readonly, int is_dev_replace)
3783 {
3784 struct scrub_ctx *sctx;
3785 int ret;
3786 struct btrfs_device *dev;
3787 unsigned int nofs_flag;
3788 struct btrfs_workqueue *scrub_workers = NULL;
3789 struct btrfs_workqueue *scrub_wr_comp = NULL;
3790 struct btrfs_workqueue *scrub_parity = NULL;
3791
3792 if (btrfs_fs_closing(fs_info))
3793 return -EINVAL;
3794
3795 if (fs_info->nodesize > BTRFS_STRIPE_LEN) {
3796 /*
3797 * in this case scrub is unable to calculate the checksum
3798 * the way scrub is implemented. Do not handle this
3799 * situation at all because it won't ever happen.
3800 */
3801 btrfs_err(fs_info,
3802 "scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails",
3803 fs_info->nodesize,
3804 BTRFS_STRIPE_LEN);
3805 return -EINVAL;
3806 }
3807
3808 if (fs_info->sectorsize != PAGE_SIZE) {
3809 /* not supported for data w/o checksums */
3810 btrfs_err_rl(fs_info,
3811 "scrub: size assumption sectorsize != PAGE_SIZE (%d != %lu) fails",
3812 fs_info->sectorsize, PAGE_SIZE);
3813 return -EINVAL;
3814 }
3815
3816 if (fs_info->nodesize >
3817 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK ||
3818 fs_info->sectorsize > PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) {
3819 /*
3820 * would exhaust the array bounds of pagev member in
3821 * struct scrub_block
3822 */
3823 btrfs_err(fs_info,
3824 "scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails",
3825 fs_info->nodesize,
3826 SCRUB_MAX_PAGES_PER_BLOCK,
3827 fs_info->sectorsize,
3828 SCRUB_MAX_PAGES_PER_BLOCK);
3829 return -EINVAL;
3830 }
3831
3832 /* Allocate outside of device_list_mutex */
3833 sctx = scrub_setup_ctx(fs_info, is_dev_replace);
3834 if (IS_ERR(sctx))
3835 return PTR_ERR(sctx);
3836
3837 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3838 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
3839 if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) &&
3840 !is_dev_replace)) {
3841 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3842 ret = -ENODEV;
3843 goto out_free_ctx;
3844 }
3845
3846 if (!is_dev_replace && !readonly &&
3847 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) {
3848 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3849 btrfs_err_in_rcu(fs_info, "scrub: device %s is not writable",
3850 rcu_str_deref(dev->name));
3851 ret = -EROFS;
3852 goto out_free_ctx;
3853 }
3854
3855 mutex_lock(&fs_info->scrub_lock);
3856 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3857 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) {
3858 mutex_unlock(&fs_info->scrub_lock);
3859 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3860 ret = -EIO;
3861 goto out_free_ctx;
3862 }
3863
3864 btrfs_dev_replace_read_lock(&fs_info->dev_replace);
3865 if (dev->scrub_ctx ||
3866 (!is_dev_replace &&
3867 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
3868 btrfs_dev_replace_read_unlock(&fs_info->dev_replace);
3869 mutex_unlock(&fs_info->scrub_lock);
3870 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3871 ret = -EINPROGRESS;
3872 goto out_free_ctx;
3873 }
3874 btrfs_dev_replace_read_unlock(&fs_info->dev_replace);
3875
3876 ret = scrub_workers_get(fs_info, is_dev_replace);
3877 if (ret) {
3878 mutex_unlock(&fs_info->scrub_lock);
3879 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3880 goto out_free_ctx;
3881 }
3882
3883 sctx->readonly = readonly;
3884 dev->scrub_ctx = sctx;
3885 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3886
3887 /*
3888 * checking @scrub_pause_req here, we can avoid
3889 * race between committing transaction and scrubbing.
3890 */
3891 __scrub_blocked_if_needed(fs_info);
3892 atomic_inc(&fs_info->scrubs_running);
3893 mutex_unlock(&fs_info->scrub_lock);
3894
3895 /*
3896 * In order to avoid deadlock with reclaim when there is a transaction
3897 * trying to pause scrub, make sure we use GFP_NOFS for all the
3898 * allocations done at btrfs_scrub_pages() and scrub_pages_for_parity()
3899 * invoked by our callees. The pausing request is done when the
3900 * transaction commit starts, and it blocks the transaction until scrub
3901 * is paused (done at specific points at scrub_stripe() or right above
3902 * before incrementing fs_info->scrubs_running).
3903 */
3904 nofs_flag = memalloc_nofs_save();
3905 if (!is_dev_replace) {
3906 /*
3907 * by holding device list mutex, we can
3908 * kick off writing super in log tree sync.
3909 */
3910 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3911 ret = scrub_supers(sctx, dev);
3912 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3913 }
3914
3915 if (!ret)
3916 ret = scrub_enumerate_chunks(sctx, dev, start, end);
3917 memalloc_nofs_restore(nofs_flag);
3918
3919 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3920 atomic_dec(&fs_info->scrubs_running);
3921 wake_up(&fs_info->scrub_pause_wait);
3922
3923 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0);
3924
3925 if (progress)
3926 memcpy(progress, &sctx->stat, sizeof(*progress));
3927
3928 mutex_lock(&fs_info->scrub_lock);
3929 dev->scrub_ctx = NULL;
3930 if (--fs_info->scrub_workers_refcnt == 0) {
3931 scrub_workers = fs_info->scrub_workers;
3932 scrub_wr_comp = fs_info->scrub_wr_completion_workers;
3933 scrub_parity = fs_info->scrub_parity_workers;
3934 }
3935 mutex_unlock(&fs_info->scrub_lock);
3936
3937 btrfs_destroy_workqueue(scrub_workers);
3938 btrfs_destroy_workqueue(scrub_wr_comp);
3939 btrfs_destroy_workqueue(scrub_parity);
3940 scrub_put_ctx(sctx);
3941
3942 return ret;
3943
3944 out_free_ctx:
3945 scrub_free_ctx(sctx);
3946
3947 return ret;
3948 }
3949
3950 void btrfs_scrub_pause(struct btrfs_fs_info *fs_info)
3951 {
3952 mutex_lock(&fs_info->scrub_lock);
3953 atomic_inc(&fs_info->scrub_pause_req);
3954 while (atomic_read(&fs_info->scrubs_paused) !=
3955 atomic_read(&fs_info->scrubs_running)) {
3956 mutex_unlock(&fs_info->scrub_lock);
3957 wait_event(fs_info->scrub_pause_wait,
3958 atomic_read(&fs_info->scrubs_paused) ==
3959 atomic_read(&fs_info->scrubs_running));
3960 mutex_lock(&fs_info->scrub_lock);
3961 }
3962 mutex_unlock(&fs_info->scrub_lock);
3963 }
3964
3965 void btrfs_scrub_continue(struct btrfs_fs_info *fs_info)
3966 {
3967 atomic_dec(&fs_info->scrub_pause_req);
3968 wake_up(&fs_info->scrub_pause_wait);
3969 }
3970
3971 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
3972 {
3973 mutex_lock(&fs_info->scrub_lock);
3974 if (!atomic_read(&fs_info->scrubs_running)) {
3975 mutex_unlock(&fs_info->scrub_lock);
3976 return -ENOTCONN;
3977 }
3978
3979 atomic_inc(&fs_info->scrub_cancel_req);
3980 while (atomic_read(&fs_info->scrubs_running)) {
3981 mutex_unlock(&fs_info->scrub_lock);
3982 wait_event(fs_info->scrub_pause_wait,
3983 atomic_read(&fs_info->scrubs_running) == 0);
3984 mutex_lock(&fs_info->scrub_lock);
3985 }
3986 atomic_dec(&fs_info->scrub_cancel_req);
3987 mutex_unlock(&fs_info->scrub_lock);
3988
3989 return 0;
3990 }
3991
3992 int btrfs_scrub_cancel_dev(struct btrfs_fs_info *fs_info,
3993 struct btrfs_device *dev)
3994 {
3995 struct scrub_ctx *sctx;
3996
3997 mutex_lock(&fs_info->scrub_lock);
3998 sctx = dev->scrub_ctx;
3999 if (!sctx) {
4000 mutex_unlock(&fs_info->scrub_lock);
4001 return -ENOTCONN;
4002 }
4003 atomic_inc(&sctx->cancel_req);
4004 while (dev->scrub_ctx) {
4005 mutex_unlock(&fs_info->scrub_lock);
4006 wait_event(fs_info->scrub_pause_wait,
4007 dev->scrub_ctx == NULL);
4008 mutex_lock(&fs_info->scrub_lock);
4009 }
4010 mutex_unlock(&fs_info->scrub_lock);
4011
4012 return 0;
4013 }
4014
4015 int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid,
4016 struct btrfs_scrub_progress *progress)
4017 {
4018 struct btrfs_device *dev;
4019 struct scrub_ctx *sctx = NULL;
4020
4021 mutex_lock(&fs_info->fs_devices->device_list_mutex);
4022 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
4023 if (dev)
4024 sctx = dev->scrub_ctx;
4025 if (sctx)
4026 memcpy(progress, &sctx->stat, sizeof(*progress));
4027 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4028
4029 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
4030 }
4031
4032 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
4033 u64 extent_logical, u64 extent_len,
4034 u64 *extent_physical,
4035 struct btrfs_device **extent_dev,
4036 int *extent_mirror_num)
4037 {
4038 u64 mapped_length;
4039 struct btrfs_bio *bbio = NULL;
4040 int ret;
4041
4042 mapped_length = extent_len;
4043 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, extent_logical,
4044 &mapped_length, &bbio, 0);
4045 if (ret || !bbio || mapped_length < extent_len ||
4046 !bbio->stripes[0].dev->bdev) {
4047 btrfs_put_bbio(bbio);
4048 return;
4049 }
4050
4051 *extent_physical = bbio->stripes[0].physical;
4052 *extent_mirror_num = bbio->mirror_num;
4053 *extent_dev = bbio->stripes[0].dev;
4054 btrfs_put_bbio(bbio);
4055 }
Linux with added FPC-III support