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[mirror_ubuntu-jammy-kernel.git] / fs / btrfs / scrub.c
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 <crypto/hash.h>
10 #include "ctree.h"
11 #include "volumes.h"
12 #include "disk-io.h"
13 #include "ordered-data.h"
14 #include "transaction.h"
15 #include "backref.h"
16 #include "extent_io.h"
17 #include "dev-replace.h"
18 #include "check-integrity.h"
19 #include "rcu-string.h"
20 #include "raid56.h"
21 #include "block-group.h"
22
23 /*
24 * This is only the first step towards a full-features scrub. It reads all
25 * extent and super block and verifies the checksums. In case a bad checksum
26 * is found or the extent cannot be read, good data will be written back if
27 * any can be found.
28 *
29 * Future enhancements:
30 * - In case an unrepairable extent is encountered, track which files are
31 * affected and report them
32 * - track and record media errors, throw out bad devices
33 * - add a mode to also read unallocated space
34 */
35
36 struct scrub_block;
37 struct scrub_ctx;
38
39 /*
40 * the following three values only influence the performance.
41 * The last one configures the number of parallel and outstanding I/O
42 * operations. The first two values configure an upper limit for the number
43 * of (dynamically allocated) pages that are added to a bio.
44 */
45 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */
46 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */
47 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */
48
49 /*
50 * the following value times PAGE_SIZE needs to be large enough to match the
51 * largest node/leaf/sector size that shall be supported.
52 * Values larger than BTRFS_STRIPE_LEN are not supported.
53 */
54 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
55
56 struct scrub_recover {
57 refcount_t refs;
58 struct btrfs_bio *bbio;
59 u64 map_length;
60 };
61
62 struct scrub_page {
63 struct scrub_block *sblock;
64 struct page *page;
65 struct btrfs_device *dev;
66 struct list_head list;
67 u64 flags; /* extent flags */
68 u64 generation;
69 u64 logical;
70 u64 physical;
71 u64 physical_for_dev_replace;
72 atomic_t refs;
73 struct {
74 unsigned int mirror_num:8;
75 unsigned int have_csum:1;
76 unsigned int io_error:1;
77 };
78 u8 csum[BTRFS_CSUM_SIZE];
79
80 struct scrub_recover *recover;
81 };
82
83 struct scrub_bio {
84 int index;
85 struct scrub_ctx *sctx;
86 struct btrfs_device *dev;
87 struct bio *bio;
88 blk_status_t status;
89 u64 logical;
90 u64 physical;
91 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO
92 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO];
93 #else
94 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO];
95 #endif
96 int page_count;
97 int next_free;
98 struct btrfs_work work;
99 };
100
101 struct scrub_block {
102 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK];
103 int page_count;
104 atomic_t outstanding_pages;
105 refcount_t refs; /* free mem on transition to zero */
106 struct scrub_ctx *sctx;
107 struct scrub_parity *sparity;
108 struct {
109 unsigned int header_error:1;
110 unsigned int checksum_error:1;
111 unsigned int no_io_error_seen:1;
112 unsigned int generation_error:1; /* also sets header_error */
113
114 /* The following is for the data used to check parity */
115 /* It is for the data with checksum */
116 unsigned int data_corrected:1;
117 };
118 struct btrfs_work work;
119 };
120
121 /* Used for the chunks with parity stripe such RAID5/6 */
122 struct scrub_parity {
123 struct scrub_ctx *sctx;
124
125 struct btrfs_device *scrub_dev;
126
127 u64 logic_start;
128
129 u64 logic_end;
130
131 int nsectors;
132
133 u64 stripe_len;
134
135 refcount_t refs;
136
137 struct list_head spages;
138
139 /* Work of parity check and repair */
140 struct btrfs_work work;
141
142 /* Mark the parity blocks which have data */
143 unsigned long *dbitmap;
144
145 /*
146 * Mark the parity blocks which have data, but errors happen when
147 * read data or check data
148 */
149 unsigned long *ebitmap;
150
151 unsigned long bitmap[0];
152 };
153
154 struct scrub_ctx {
155 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX];
156 struct btrfs_fs_info *fs_info;
157 int first_free;
158 int curr;
159 atomic_t bios_in_flight;
160 atomic_t workers_pending;
161 spinlock_t list_lock;
162 wait_queue_head_t list_wait;
163 u16 csum_size;
164 struct list_head csum_list;
165 atomic_t cancel_req;
166 int readonly;
167 int pages_per_rd_bio;
168
169 int is_dev_replace;
170
171 struct scrub_bio *wr_curr_bio;
172 struct mutex wr_lock;
173 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
174 struct btrfs_device *wr_tgtdev;
175 bool flush_all_writes;
176
177 /*
178 * statistics
179 */
180 struct btrfs_scrub_progress stat;
181 spinlock_t stat_lock;
182
183 /*
184 * Use a ref counter to avoid use-after-free issues. Scrub workers
185 * decrement bios_in_flight and workers_pending and then do a wakeup
186 * on the list_wait wait queue. We must ensure the main scrub task
187 * doesn't free the scrub context before or while the workers are
188 * doing the wakeup() call.
189 */
190 refcount_t refs;
191 };
192
193 struct scrub_warning {
194 struct btrfs_path *path;
195 u64 extent_item_size;
196 const char *errstr;
197 u64 physical;
198 u64 logical;
199 struct btrfs_device *dev;
200 };
201
202 struct full_stripe_lock {
203 struct rb_node node;
204 u64 logical;
205 u64 refs;
206 struct mutex mutex;
207 };
208
209 static void scrub_pending_bio_inc(struct scrub_ctx *sctx);
210 static void scrub_pending_bio_dec(struct scrub_ctx *sctx);
211 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
212 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
213 struct scrub_block *sblocks_for_recheck);
214 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
215 struct scrub_block *sblock,
216 int retry_failed_mirror);
217 static void scrub_recheck_block_checksum(struct scrub_block *sblock);
218 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
219 struct scrub_block *sblock_good);
220 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
221 struct scrub_block *sblock_good,
222 int page_num, int force_write);
223 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock);
224 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
225 int page_num);
226 static int scrub_checksum_data(struct scrub_block *sblock);
227 static int scrub_checksum_tree_block(struct scrub_block *sblock);
228 static int scrub_checksum_super(struct scrub_block *sblock);
229 static void scrub_block_get(struct scrub_block *sblock);
230 static void scrub_block_put(struct scrub_block *sblock);
231 static void scrub_page_get(struct scrub_page *spage);
232 static void scrub_page_put(struct scrub_page *spage);
233 static void scrub_parity_get(struct scrub_parity *sparity);
234 static void scrub_parity_put(struct scrub_parity *sparity);
235 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
236 struct scrub_page *spage);
237 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
238 u64 physical, struct btrfs_device *dev, u64 flags,
239 u64 gen, int mirror_num, u8 *csum, int force,
240 u64 physical_for_dev_replace);
241 static void scrub_bio_end_io(struct bio *bio);
242 static void scrub_bio_end_io_worker(struct btrfs_work *work);
243 static void scrub_block_complete(struct scrub_block *sblock);
244 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
245 u64 extent_logical, u64 extent_len,
246 u64 *extent_physical,
247 struct btrfs_device **extent_dev,
248 int *extent_mirror_num);
249 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
250 struct scrub_page *spage);
251 static void scrub_wr_submit(struct scrub_ctx *sctx);
252 static void scrub_wr_bio_end_io(struct bio *bio);
253 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work);
254 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
255 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
256 static void scrub_put_ctx(struct scrub_ctx *sctx);
257
258 static inline int scrub_is_page_on_raid56(struct scrub_page *page)
259 {
260 return page->recover &&
261 (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
262 }
263
264 static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
265 {
266 refcount_inc(&sctx->refs);
267 atomic_inc(&sctx->bios_in_flight);
268 }
269
270 static void scrub_pending_bio_dec(struct scrub_ctx *sctx)
271 {
272 atomic_dec(&sctx->bios_in_flight);
273 wake_up(&sctx->list_wait);
274 scrub_put_ctx(sctx);
275 }
276
277 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
278 {
279 while (atomic_read(&fs_info->scrub_pause_req)) {
280 mutex_unlock(&fs_info->scrub_lock);
281 wait_event(fs_info->scrub_pause_wait,
282 atomic_read(&fs_info->scrub_pause_req) == 0);
283 mutex_lock(&fs_info->scrub_lock);
284 }
285 }
286
287 static void scrub_pause_on(struct btrfs_fs_info *fs_info)
288 {
289 atomic_inc(&fs_info->scrubs_paused);
290 wake_up(&fs_info->scrub_pause_wait);
291 }
292
293 static void scrub_pause_off(struct btrfs_fs_info *fs_info)
294 {
295 mutex_lock(&fs_info->scrub_lock);
296 __scrub_blocked_if_needed(fs_info);
297 atomic_dec(&fs_info->scrubs_paused);
298 mutex_unlock(&fs_info->scrub_lock);
299
300 wake_up(&fs_info->scrub_pause_wait);
301 }
302
303 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
304 {
305 scrub_pause_on(fs_info);
306 scrub_pause_off(fs_info);
307 }
308
309 /*
310 * Insert new full stripe lock into full stripe locks tree
311 *
312 * Return pointer to existing or newly inserted full_stripe_lock structure if
313 * everything works well.
314 * Return ERR_PTR(-ENOMEM) if we failed to allocate memory
315 *
316 * NOTE: caller must hold full_stripe_locks_root->lock before calling this
317 * function
318 */
319 static struct full_stripe_lock *insert_full_stripe_lock(
320 struct btrfs_full_stripe_locks_tree *locks_root,
321 u64 fstripe_logical)
322 {
323 struct rb_node **p;
324 struct rb_node *parent = NULL;
325 struct full_stripe_lock *entry;
326 struct full_stripe_lock *ret;
327
328 lockdep_assert_held(&locks_root->lock);
329
330 p = &locks_root->root.rb_node;
331 while (*p) {
332 parent = *p;
333 entry = rb_entry(parent, struct full_stripe_lock, node);
334 if (fstripe_logical < entry->logical) {
335 p = &(*p)->rb_left;
336 } else if (fstripe_logical > entry->logical) {
337 p = &(*p)->rb_right;
338 } else {
339 entry->refs++;
340 return entry;
341 }
342 }
343
344 /*
345 * Insert new lock.
346 */
347 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
348 if (!ret)
349 return ERR_PTR(-ENOMEM);
350 ret->logical = fstripe_logical;
351 ret->refs = 1;
352 mutex_init(&ret->mutex);
353
354 rb_link_node(&ret->node, parent, p);
355 rb_insert_color(&ret->node, &locks_root->root);
356 return ret;
357 }
358
359 /*
360 * Search for a full stripe lock of a block group
361 *
362 * Return pointer to existing full stripe lock if found
363 * Return NULL if not found
364 */
365 static struct full_stripe_lock *search_full_stripe_lock(
366 struct btrfs_full_stripe_locks_tree *locks_root,
367 u64 fstripe_logical)
368 {
369 struct rb_node *node;
370 struct full_stripe_lock *entry;
371
372 lockdep_assert_held(&locks_root->lock);
373
374 node = locks_root->root.rb_node;
375 while (node) {
376 entry = rb_entry(node, struct full_stripe_lock, node);
377 if (fstripe_logical < entry->logical)
378 node = node->rb_left;
379 else if (fstripe_logical > entry->logical)
380 node = node->rb_right;
381 else
382 return entry;
383 }
384 return NULL;
385 }
386
387 /*
388 * Helper to get full stripe logical from a normal bytenr.
389 *
390 * Caller must ensure @cache is a RAID56 block group.
391 */
392 static u64 get_full_stripe_logical(struct btrfs_block_group *cache, u64 bytenr)
393 {
394 u64 ret;
395
396 /*
397 * Due to chunk item size limit, full stripe length should not be
398 * larger than U32_MAX. Just a sanity check here.
399 */
400 WARN_ON_ONCE(cache->full_stripe_len >= U32_MAX);
401
402 /*
403 * round_down() can only handle power of 2, while RAID56 full
404 * stripe length can be 64KiB * n, so we need to manually round down.
405 */
406 ret = div64_u64(bytenr - cache->start, cache->full_stripe_len) *
407 cache->full_stripe_len + cache->start;
408 return ret;
409 }
410
411 /*
412 * Lock a full stripe to avoid concurrency of recovery and read
413 *
414 * It's only used for profiles with parities (RAID5/6), for other profiles it
415 * does nothing.
416 *
417 * Return 0 if we locked full stripe covering @bytenr, with a mutex held.
418 * So caller must call unlock_full_stripe() at the same context.
419 *
420 * Return <0 if encounters error.
421 */
422 static int lock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
423 bool *locked_ret)
424 {
425 struct btrfs_block_group *bg_cache;
426 struct btrfs_full_stripe_locks_tree *locks_root;
427 struct full_stripe_lock *existing;
428 u64 fstripe_start;
429 int ret = 0;
430
431 *locked_ret = false;
432 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
433 if (!bg_cache) {
434 ASSERT(0);
435 return -ENOENT;
436 }
437
438 /* Profiles not based on parity don't need full stripe lock */
439 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
440 goto out;
441 locks_root = &bg_cache->full_stripe_locks_root;
442
443 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
444
445 /* Now insert the full stripe lock */
446 mutex_lock(&locks_root->lock);
447 existing = insert_full_stripe_lock(locks_root, fstripe_start);
448 mutex_unlock(&locks_root->lock);
449 if (IS_ERR(existing)) {
450 ret = PTR_ERR(existing);
451 goto out;
452 }
453 mutex_lock(&existing->mutex);
454 *locked_ret = true;
455 out:
456 btrfs_put_block_group(bg_cache);
457 return ret;
458 }
459
460 /*
461 * Unlock a full stripe.
462 *
463 * NOTE: Caller must ensure it's the same context calling corresponding
464 * lock_full_stripe().
465 *
466 * Return 0 if we unlock full stripe without problem.
467 * Return <0 for error
468 */
469 static int unlock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
470 bool locked)
471 {
472 struct btrfs_block_group *bg_cache;
473 struct btrfs_full_stripe_locks_tree *locks_root;
474 struct full_stripe_lock *fstripe_lock;
475 u64 fstripe_start;
476 bool freeit = false;
477 int ret = 0;
478
479 /* If we didn't acquire full stripe lock, no need to continue */
480 if (!locked)
481 return 0;
482
483 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
484 if (!bg_cache) {
485 ASSERT(0);
486 return -ENOENT;
487 }
488 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
489 goto out;
490
491 locks_root = &bg_cache->full_stripe_locks_root;
492 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
493
494 mutex_lock(&locks_root->lock);
495 fstripe_lock = search_full_stripe_lock(locks_root, fstripe_start);
496 /* Unpaired unlock_full_stripe() detected */
497 if (!fstripe_lock) {
498 WARN_ON(1);
499 ret = -ENOENT;
500 mutex_unlock(&locks_root->lock);
501 goto out;
502 }
503
504 if (fstripe_lock->refs == 0) {
505 WARN_ON(1);
506 btrfs_warn(fs_info, "full stripe lock at %llu refcount underflow",
507 fstripe_lock->logical);
508 } else {
509 fstripe_lock->refs--;
510 }
511
512 if (fstripe_lock->refs == 0) {
513 rb_erase(&fstripe_lock->node, &locks_root->root);
514 freeit = true;
515 }
516 mutex_unlock(&locks_root->lock);
517
518 mutex_unlock(&fstripe_lock->mutex);
519 if (freeit)
520 kfree(fstripe_lock);
521 out:
522 btrfs_put_block_group(bg_cache);
523 return ret;
524 }
525
526 static void scrub_free_csums(struct scrub_ctx *sctx)
527 {
528 while (!list_empty(&sctx->csum_list)) {
529 struct btrfs_ordered_sum *sum;
530 sum = list_first_entry(&sctx->csum_list,
531 struct btrfs_ordered_sum, list);
532 list_del(&sum->list);
533 kfree(sum);
534 }
535 }
536
537 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
538 {
539 int i;
540
541 if (!sctx)
542 return;
543
544 /* this can happen when scrub is cancelled */
545 if (sctx->curr != -1) {
546 struct scrub_bio *sbio = sctx->bios[sctx->curr];
547
548 for (i = 0; i < sbio->page_count; i++) {
549 WARN_ON(!sbio->pagev[i]->page);
550 scrub_block_put(sbio->pagev[i]->sblock);
551 }
552 bio_put(sbio->bio);
553 }
554
555 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
556 struct scrub_bio *sbio = sctx->bios[i];
557
558 if (!sbio)
559 break;
560 kfree(sbio);
561 }
562
563 kfree(sctx->wr_curr_bio);
564 scrub_free_csums(sctx);
565 kfree(sctx);
566 }
567
568 static void scrub_put_ctx(struct scrub_ctx *sctx)
569 {
570 if (refcount_dec_and_test(&sctx->refs))
571 scrub_free_ctx(sctx);
572 }
573
574 static noinline_for_stack struct scrub_ctx *scrub_setup_ctx(
575 struct btrfs_fs_info *fs_info, int is_dev_replace)
576 {
577 struct scrub_ctx *sctx;
578 int i;
579
580 sctx = kzalloc(sizeof(*sctx), GFP_KERNEL);
581 if (!sctx)
582 goto nomem;
583 refcount_set(&sctx->refs, 1);
584 sctx->is_dev_replace = is_dev_replace;
585 sctx->pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
586 sctx->curr = -1;
587 sctx->fs_info = fs_info;
588 INIT_LIST_HEAD(&sctx->csum_list);
589 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
590 struct scrub_bio *sbio;
591
592 sbio = kzalloc(sizeof(*sbio), GFP_KERNEL);
593 if (!sbio)
594 goto nomem;
595 sctx->bios[i] = sbio;
596
597 sbio->index = i;
598 sbio->sctx = sctx;
599 sbio->page_count = 0;
600 btrfs_init_work(&sbio->work, scrub_bio_end_io_worker, NULL,
601 NULL);
602
603 if (i != SCRUB_BIOS_PER_SCTX - 1)
604 sctx->bios[i]->next_free = i + 1;
605 else
606 sctx->bios[i]->next_free = -1;
607 }
608 sctx->first_free = 0;
609 atomic_set(&sctx->bios_in_flight, 0);
610 atomic_set(&sctx->workers_pending, 0);
611 atomic_set(&sctx->cancel_req, 0);
612 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
613
614 spin_lock_init(&sctx->list_lock);
615 spin_lock_init(&sctx->stat_lock);
616 init_waitqueue_head(&sctx->list_wait);
617
618 WARN_ON(sctx->wr_curr_bio != NULL);
619 mutex_init(&sctx->wr_lock);
620 sctx->wr_curr_bio = NULL;
621 if (is_dev_replace) {
622 WARN_ON(!fs_info->dev_replace.tgtdev);
623 sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
624 sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
625 sctx->flush_all_writes = false;
626 }
627
628 return sctx;
629
630 nomem:
631 scrub_free_ctx(sctx);
632 return ERR_PTR(-ENOMEM);
633 }
634
635 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root,
636 void *warn_ctx)
637 {
638 u64 isize;
639 u32 nlink;
640 int ret;
641 int i;
642 unsigned nofs_flag;
643 struct extent_buffer *eb;
644 struct btrfs_inode_item *inode_item;
645 struct scrub_warning *swarn = warn_ctx;
646 struct btrfs_fs_info *fs_info = swarn->dev->fs_info;
647 struct inode_fs_paths *ipath = NULL;
648 struct btrfs_root *local_root;
649 struct btrfs_key root_key;
650 struct btrfs_key key;
651
652 root_key.objectid = root;
653 root_key.type = BTRFS_ROOT_ITEM_KEY;
654 root_key.offset = (u64)-1;
655 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
656 if (IS_ERR(local_root)) {
657 ret = PTR_ERR(local_root);
658 goto err;
659 }
660
661 /*
662 * this makes the path point to (inum INODE_ITEM ioff)
663 */
664 key.objectid = inum;
665 key.type = BTRFS_INODE_ITEM_KEY;
666 key.offset = 0;
667
668 ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0);
669 if (ret) {
670 btrfs_release_path(swarn->path);
671 goto err;
672 }
673
674 eb = swarn->path->nodes[0];
675 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
676 struct btrfs_inode_item);
677 isize = btrfs_inode_size(eb, inode_item);
678 nlink = btrfs_inode_nlink(eb, inode_item);
679 btrfs_release_path(swarn->path);
680
681 /*
682 * init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub
683 * uses GFP_NOFS in this context, so we keep it consistent but it does
684 * not seem to be strictly necessary.
685 */
686 nofs_flag = memalloc_nofs_save();
687 ipath = init_ipath(4096, local_root, swarn->path);
688 memalloc_nofs_restore(nofs_flag);
689 if (IS_ERR(ipath)) {
690 ret = PTR_ERR(ipath);
691 ipath = NULL;
692 goto err;
693 }
694 ret = paths_from_inode(inum, ipath);
695
696 if (ret < 0)
697 goto err;
698
699 /*
700 * we deliberately ignore the bit ipath might have been too small to
701 * hold all of the paths here
702 */
703 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
704 btrfs_warn_in_rcu(fs_info,
705 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %llu, links %u (path: %s)",
706 swarn->errstr, swarn->logical,
707 rcu_str_deref(swarn->dev->name),
708 swarn->physical,
709 root, inum, offset,
710 min(isize - offset, (u64)PAGE_SIZE), nlink,
711 (char *)(unsigned long)ipath->fspath->val[i]);
712
713 free_ipath(ipath);
714 return 0;
715
716 err:
717 btrfs_warn_in_rcu(fs_info,
718 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d",
719 swarn->errstr, swarn->logical,
720 rcu_str_deref(swarn->dev->name),
721 swarn->physical,
722 root, inum, offset, ret);
723
724 free_ipath(ipath);
725 return 0;
726 }
727
728 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
729 {
730 struct btrfs_device *dev;
731 struct btrfs_fs_info *fs_info;
732 struct btrfs_path *path;
733 struct btrfs_key found_key;
734 struct extent_buffer *eb;
735 struct btrfs_extent_item *ei;
736 struct scrub_warning swarn;
737 unsigned long ptr = 0;
738 u64 extent_item_pos;
739 u64 flags = 0;
740 u64 ref_root;
741 u32 item_size;
742 u8 ref_level = 0;
743 int ret;
744
745 WARN_ON(sblock->page_count < 1);
746 dev = sblock->pagev[0]->dev;
747 fs_info = sblock->sctx->fs_info;
748
749 path = btrfs_alloc_path();
750 if (!path)
751 return;
752
753 swarn.physical = sblock->pagev[0]->physical;
754 swarn.logical = sblock->pagev[0]->logical;
755 swarn.errstr = errstr;
756 swarn.dev = NULL;
757
758 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
759 &flags);
760 if (ret < 0)
761 goto out;
762
763 extent_item_pos = swarn.logical - found_key.objectid;
764 swarn.extent_item_size = found_key.offset;
765
766 eb = path->nodes[0];
767 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
768 item_size = btrfs_item_size_nr(eb, path->slots[0]);
769
770 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
771 do {
772 ret = tree_backref_for_extent(&ptr, eb, &found_key, ei,
773 item_size, &ref_root,
774 &ref_level);
775 btrfs_warn_in_rcu(fs_info,
776 "%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu",
777 errstr, swarn.logical,
778 rcu_str_deref(dev->name),
779 swarn.physical,
780 ref_level ? "node" : "leaf",
781 ret < 0 ? -1 : ref_level,
782 ret < 0 ? -1 : ref_root);
783 } while (ret != 1);
784 btrfs_release_path(path);
785 } else {
786 btrfs_release_path(path);
787 swarn.path = path;
788 swarn.dev = dev;
789 iterate_extent_inodes(fs_info, found_key.objectid,
790 extent_item_pos, 1,
791 scrub_print_warning_inode, &swarn, false);
792 }
793
794 out:
795 btrfs_free_path(path);
796 }
797
798 static inline void scrub_get_recover(struct scrub_recover *recover)
799 {
800 refcount_inc(&recover->refs);
801 }
802
803 static inline void scrub_put_recover(struct btrfs_fs_info *fs_info,
804 struct scrub_recover *recover)
805 {
806 if (refcount_dec_and_test(&recover->refs)) {
807 btrfs_bio_counter_dec(fs_info);
808 btrfs_put_bbio(recover->bbio);
809 kfree(recover);
810 }
811 }
812
813 /*
814 * scrub_handle_errored_block gets called when either verification of the
815 * pages failed or the bio failed to read, e.g. with EIO. In the latter
816 * case, this function handles all pages in the bio, even though only one
817 * may be bad.
818 * The goal of this function is to repair the errored block by using the
819 * contents of one of the mirrors.
820 */
821 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
822 {
823 struct scrub_ctx *sctx = sblock_to_check->sctx;
824 struct btrfs_device *dev;
825 struct btrfs_fs_info *fs_info;
826 u64 logical;
827 unsigned int failed_mirror_index;
828 unsigned int is_metadata;
829 unsigned int have_csum;
830 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
831 struct scrub_block *sblock_bad;
832 int ret;
833 int mirror_index;
834 int page_num;
835 int success;
836 bool full_stripe_locked;
837 unsigned int nofs_flag;
838 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
839 DEFAULT_RATELIMIT_BURST);
840
841 BUG_ON(sblock_to_check->page_count < 1);
842 fs_info = sctx->fs_info;
843 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) {
844 /*
845 * if we find an error in a super block, we just report it.
846 * They will get written with the next transaction commit
847 * anyway
848 */
849 spin_lock(&sctx->stat_lock);
850 ++sctx->stat.super_errors;
851 spin_unlock(&sctx->stat_lock);
852 return 0;
853 }
854 logical = sblock_to_check->pagev[0]->logical;
855 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1);
856 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1;
857 is_metadata = !(sblock_to_check->pagev[0]->flags &
858 BTRFS_EXTENT_FLAG_DATA);
859 have_csum = sblock_to_check->pagev[0]->have_csum;
860 dev = sblock_to_check->pagev[0]->dev;
861
862 /*
863 * We must use GFP_NOFS because the scrub task might be waiting for a
864 * worker task executing this function and in turn a transaction commit
865 * might be waiting the scrub task to pause (which needs to wait for all
866 * the worker tasks to complete before pausing).
867 * We do allocations in the workers through insert_full_stripe_lock()
868 * and scrub_add_page_to_wr_bio(), which happens down the call chain of
869 * this function.
870 */
871 nofs_flag = memalloc_nofs_save();
872 /*
873 * For RAID5/6, race can happen for a different device scrub thread.
874 * For data corruption, Parity and Data threads will both try
875 * to recovery the data.
876 * Race can lead to doubly added csum error, or even unrecoverable
877 * error.
878 */
879 ret = lock_full_stripe(fs_info, logical, &full_stripe_locked);
880 if (ret < 0) {
881 memalloc_nofs_restore(nofs_flag);
882 spin_lock(&sctx->stat_lock);
883 if (ret == -ENOMEM)
884 sctx->stat.malloc_errors++;
885 sctx->stat.read_errors++;
886 sctx->stat.uncorrectable_errors++;
887 spin_unlock(&sctx->stat_lock);
888 return ret;
889 }
890
891 /*
892 * read all mirrors one after the other. This includes to
893 * re-read the extent or metadata block that failed (that was
894 * the cause that this fixup code is called) another time,
895 * page by page this time in order to know which pages
896 * caused I/O errors and which ones are good (for all mirrors).
897 * It is the goal to handle the situation when more than one
898 * mirror contains I/O errors, but the errors do not
899 * overlap, i.e. the data can be repaired by selecting the
900 * pages from those mirrors without I/O error on the
901 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
902 * would be that mirror #1 has an I/O error on the first page,
903 * the second page is good, and mirror #2 has an I/O error on
904 * the second page, but the first page is good.
905 * Then the first page of the first mirror can be repaired by
906 * taking the first page of the second mirror, and the
907 * second page of the second mirror can be repaired by
908 * copying the contents of the 2nd page of the 1st mirror.
909 * One more note: if the pages of one mirror contain I/O
910 * errors, the checksum cannot be verified. In order to get
911 * the best data for repairing, the first attempt is to find
912 * a mirror without I/O errors and with a validated checksum.
913 * Only if this is not possible, the pages are picked from
914 * mirrors with I/O errors without considering the checksum.
915 * If the latter is the case, at the end, the checksum of the
916 * repaired area is verified in order to correctly maintain
917 * the statistics.
918 */
919
920 sblocks_for_recheck = kcalloc(BTRFS_MAX_MIRRORS,
921 sizeof(*sblocks_for_recheck), GFP_KERNEL);
922 if (!sblocks_for_recheck) {
923 spin_lock(&sctx->stat_lock);
924 sctx->stat.malloc_errors++;
925 sctx->stat.read_errors++;
926 sctx->stat.uncorrectable_errors++;
927 spin_unlock(&sctx->stat_lock);
928 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
929 goto out;
930 }
931
932 /* setup the context, map the logical blocks and alloc the pages */
933 ret = scrub_setup_recheck_block(sblock_to_check, sblocks_for_recheck);
934 if (ret) {
935 spin_lock(&sctx->stat_lock);
936 sctx->stat.read_errors++;
937 sctx->stat.uncorrectable_errors++;
938 spin_unlock(&sctx->stat_lock);
939 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
940 goto out;
941 }
942 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
943 sblock_bad = sblocks_for_recheck + failed_mirror_index;
944
945 /* build and submit the bios for the failed mirror, check checksums */
946 scrub_recheck_block(fs_info, sblock_bad, 1);
947
948 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
949 sblock_bad->no_io_error_seen) {
950 /*
951 * the error disappeared after reading page by page, or
952 * the area was part of a huge bio and other parts of the
953 * bio caused I/O errors, or the block layer merged several
954 * read requests into one and the error is caused by a
955 * different bio (usually one of the two latter cases is
956 * the cause)
957 */
958 spin_lock(&sctx->stat_lock);
959 sctx->stat.unverified_errors++;
960 sblock_to_check->data_corrected = 1;
961 spin_unlock(&sctx->stat_lock);
962
963 if (sctx->is_dev_replace)
964 scrub_write_block_to_dev_replace(sblock_bad);
965 goto out;
966 }
967
968 if (!sblock_bad->no_io_error_seen) {
969 spin_lock(&sctx->stat_lock);
970 sctx->stat.read_errors++;
971 spin_unlock(&sctx->stat_lock);
972 if (__ratelimit(&_rs))
973 scrub_print_warning("i/o error", sblock_to_check);
974 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
975 } else if (sblock_bad->checksum_error) {
976 spin_lock(&sctx->stat_lock);
977 sctx->stat.csum_errors++;
978 spin_unlock(&sctx->stat_lock);
979 if (__ratelimit(&_rs))
980 scrub_print_warning("checksum error", sblock_to_check);
981 btrfs_dev_stat_inc_and_print(dev,
982 BTRFS_DEV_STAT_CORRUPTION_ERRS);
983 } else if (sblock_bad->header_error) {
984 spin_lock(&sctx->stat_lock);
985 sctx->stat.verify_errors++;
986 spin_unlock(&sctx->stat_lock);
987 if (__ratelimit(&_rs))
988 scrub_print_warning("checksum/header error",
989 sblock_to_check);
990 if (sblock_bad->generation_error)
991 btrfs_dev_stat_inc_and_print(dev,
992 BTRFS_DEV_STAT_GENERATION_ERRS);
993 else
994 btrfs_dev_stat_inc_and_print(dev,
995 BTRFS_DEV_STAT_CORRUPTION_ERRS);
996 }
997
998 if (sctx->readonly) {
999 ASSERT(!sctx->is_dev_replace);
1000 goto out;
1001 }
1002
1003 /*
1004 * now build and submit the bios for the other mirrors, check
1005 * checksums.
1006 * First try to pick the mirror which is completely without I/O
1007 * errors and also does not have a checksum error.
1008 * If one is found, and if a checksum is present, the full block
1009 * that is known to contain an error is rewritten. Afterwards
1010 * the block is known to be corrected.
1011 * If a mirror is found which is completely correct, and no
1012 * checksum is present, only those pages are rewritten that had
1013 * an I/O error in the block to be repaired, since it cannot be
1014 * determined, which copy of the other pages is better (and it
1015 * could happen otherwise that a correct page would be
1016 * overwritten by a bad one).
1017 */
1018 for (mirror_index = 0; ;mirror_index++) {
1019 struct scrub_block *sblock_other;
1020
1021 if (mirror_index == failed_mirror_index)
1022 continue;
1023
1024 /* raid56's mirror can be more than BTRFS_MAX_MIRRORS */
1025 if (!scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1026 if (mirror_index >= BTRFS_MAX_MIRRORS)
1027 break;
1028 if (!sblocks_for_recheck[mirror_index].page_count)
1029 break;
1030
1031 sblock_other = sblocks_for_recheck + mirror_index;
1032 } else {
1033 struct scrub_recover *r = sblock_bad->pagev[0]->recover;
1034 int max_allowed = r->bbio->num_stripes -
1035 r->bbio->num_tgtdevs;
1036
1037 if (mirror_index >= max_allowed)
1038 break;
1039 if (!sblocks_for_recheck[1].page_count)
1040 break;
1041
1042 ASSERT(failed_mirror_index == 0);
1043 sblock_other = sblocks_for_recheck + 1;
1044 sblock_other->pagev[0]->mirror_num = 1 + mirror_index;
1045 }
1046
1047 /* build and submit the bios, check checksums */
1048 scrub_recheck_block(fs_info, sblock_other, 0);
1049
1050 if (!sblock_other->header_error &&
1051 !sblock_other->checksum_error &&
1052 sblock_other->no_io_error_seen) {
1053 if (sctx->is_dev_replace) {
1054 scrub_write_block_to_dev_replace(sblock_other);
1055 goto corrected_error;
1056 } else {
1057 ret = scrub_repair_block_from_good_copy(
1058 sblock_bad, sblock_other);
1059 if (!ret)
1060 goto corrected_error;
1061 }
1062 }
1063 }
1064
1065 if (sblock_bad->no_io_error_seen && !sctx->is_dev_replace)
1066 goto did_not_correct_error;
1067
1068 /*
1069 * In case of I/O errors in the area that is supposed to be
1070 * repaired, continue by picking good copies of those pages.
1071 * Select the good pages from mirrors to rewrite bad pages from
1072 * the area to fix. Afterwards verify the checksum of the block
1073 * that is supposed to be repaired. This verification step is
1074 * only done for the purpose of statistic counting and for the
1075 * final scrub report, whether errors remain.
1076 * A perfect algorithm could make use of the checksum and try
1077 * all possible combinations of pages from the different mirrors
1078 * until the checksum verification succeeds. For example, when
1079 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
1080 * of mirror #2 is readable but the final checksum test fails,
1081 * then the 2nd page of mirror #3 could be tried, whether now
1082 * the final checksum succeeds. But this would be a rare
1083 * exception and is therefore not implemented. At least it is
1084 * avoided that the good copy is overwritten.
1085 * A more useful improvement would be to pick the sectors
1086 * without I/O error based on sector sizes (512 bytes on legacy
1087 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
1088 * mirror could be repaired by taking 512 byte of a different
1089 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
1090 * area are unreadable.
1091 */
1092 success = 1;
1093 for (page_num = 0; page_num < sblock_bad->page_count;
1094 page_num++) {
1095 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1096 struct scrub_block *sblock_other = NULL;
1097
1098 /* skip no-io-error page in scrub */
1099 if (!page_bad->io_error && !sctx->is_dev_replace)
1100 continue;
1101
1102 if (scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1103 /*
1104 * In case of dev replace, if raid56 rebuild process
1105 * didn't work out correct data, then copy the content
1106 * in sblock_bad to make sure target device is identical
1107 * to source device, instead of writing garbage data in
1108 * sblock_for_recheck array to target device.
1109 */
1110 sblock_other = NULL;
1111 } else if (page_bad->io_error) {
1112 /* try to find no-io-error page in mirrors */
1113 for (mirror_index = 0;
1114 mirror_index < BTRFS_MAX_MIRRORS &&
1115 sblocks_for_recheck[mirror_index].page_count > 0;
1116 mirror_index++) {
1117 if (!sblocks_for_recheck[mirror_index].
1118 pagev[page_num]->io_error) {
1119 sblock_other = sblocks_for_recheck +
1120 mirror_index;
1121 break;
1122 }
1123 }
1124 if (!sblock_other)
1125 success = 0;
1126 }
1127
1128 if (sctx->is_dev_replace) {
1129 /*
1130 * did not find a mirror to fetch the page
1131 * from. scrub_write_page_to_dev_replace()
1132 * handles this case (page->io_error), by
1133 * filling the block with zeros before
1134 * submitting the write request
1135 */
1136 if (!sblock_other)
1137 sblock_other = sblock_bad;
1138
1139 if (scrub_write_page_to_dev_replace(sblock_other,
1140 page_num) != 0) {
1141 atomic64_inc(
1142 &fs_info->dev_replace.num_write_errors);
1143 success = 0;
1144 }
1145 } else if (sblock_other) {
1146 ret = scrub_repair_page_from_good_copy(sblock_bad,
1147 sblock_other,
1148 page_num, 0);
1149 if (0 == ret)
1150 page_bad->io_error = 0;
1151 else
1152 success = 0;
1153 }
1154 }
1155
1156 if (success && !sctx->is_dev_replace) {
1157 if (is_metadata || have_csum) {
1158 /*
1159 * need to verify the checksum now that all
1160 * sectors on disk are repaired (the write
1161 * request for data to be repaired is on its way).
1162 * Just be lazy and use scrub_recheck_block()
1163 * which re-reads the data before the checksum
1164 * is verified, but most likely the data comes out
1165 * of the page cache.
1166 */
1167 scrub_recheck_block(fs_info, sblock_bad, 1);
1168 if (!sblock_bad->header_error &&
1169 !sblock_bad->checksum_error &&
1170 sblock_bad->no_io_error_seen)
1171 goto corrected_error;
1172 else
1173 goto did_not_correct_error;
1174 } else {
1175 corrected_error:
1176 spin_lock(&sctx->stat_lock);
1177 sctx->stat.corrected_errors++;
1178 sblock_to_check->data_corrected = 1;
1179 spin_unlock(&sctx->stat_lock);
1180 btrfs_err_rl_in_rcu(fs_info,
1181 "fixed up error at logical %llu on dev %s",
1182 logical, rcu_str_deref(dev->name));
1183 }
1184 } else {
1185 did_not_correct_error:
1186 spin_lock(&sctx->stat_lock);
1187 sctx->stat.uncorrectable_errors++;
1188 spin_unlock(&sctx->stat_lock);
1189 btrfs_err_rl_in_rcu(fs_info,
1190 "unable to fixup (regular) error at logical %llu on dev %s",
1191 logical, rcu_str_deref(dev->name));
1192 }
1193
1194 out:
1195 if (sblocks_for_recheck) {
1196 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
1197 mirror_index++) {
1198 struct scrub_block *sblock = sblocks_for_recheck +
1199 mirror_index;
1200 struct scrub_recover *recover;
1201 int page_index;
1202
1203 for (page_index = 0; page_index < sblock->page_count;
1204 page_index++) {
1205 sblock->pagev[page_index]->sblock = NULL;
1206 recover = sblock->pagev[page_index]->recover;
1207 if (recover) {
1208 scrub_put_recover(fs_info, recover);
1209 sblock->pagev[page_index]->recover =
1210 NULL;
1211 }
1212 scrub_page_put(sblock->pagev[page_index]);
1213 }
1214 }
1215 kfree(sblocks_for_recheck);
1216 }
1217
1218 ret = unlock_full_stripe(fs_info, logical, full_stripe_locked);
1219 memalloc_nofs_restore(nofs_flag);
1220 if (ret < 0)
1221 return ret;
1222 return 0;
1223 }
1224
1225 static inline int scrub_nr_raid_mirrors(struct btrfs_bio *bbio)
1226 {
1227 if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID5)
1228 return 2;
1229 else if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID6)
1230 return 3;
1231 else
1232 return (int)bbio->num_stripes;
1233 }
1234
1235 static inline void scrub_stripe_index_and_offset(u64 logical, u64 map_type,
1236 u64 *raid_map,
1237 u64 mapped_length,
1238 int nstripes, int mirror,
1239 int *stripe_index,
1240 u64 *stripe_offset)
1241 {
1242 int i;
1243
1244 if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
1245 /* RAID5/6 */
1246 for (i = 0; i < nstripes; i++) {
1247 if (raid_map[i] == RAID6_Q_STRIPE ||
1248 raid_map[i] == RAID5_P_STRIPE)
1249 continue;
1250
1251 if (logical >= raid_map[i] &&
1252 logical < raid_map[i] + mapped_length)
1253 break;
1254 }
1255
1256 *stripe_index = i;
1257 *stripe_offset = logical - raid_map[i];
1258 } else {
1259 /* The other RAID type */
1260 *stripe_index = mirror;
1261 *stripe_offset = 0;
1262 }
1263 }
1264
1265 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
1266 struct scrub_block *sblocks_for_recheck)
1267 {
1268 struct scrub_ctx *sctx = original_sblock->sctx;
1269 struct btrfs_fs_info *fs_info = sctx->fs_info;
1270 u64 length = original_sblock->page_count * PAGE_SIZE;
1271 u64 logical = original_sblock->pagev[0]->logical;
1272 u64 generation = original_sblock->pagev[0]->generation;
1273 u64 flags = original_sblock->pagev[0]->flags;
1274 u64 have_csum = original_sblock->pagev[0]->have_csum;
1275 struct scrub_recover *recover;
1276 struct btrfs_bio *bbio;
1277 u64 sublen;
1278 u64 mapped_length;
1279 u64 stripe_offset;
1280 int stripe_index;
1281 int page_index = 0;
1282 int mirror_index;
1283 int nmirrors;
1284 int ret;
1285
1286 /*
1287 * note: the two members refs and outstanding_pages
1288 * are not used (and not set) in the blocks that are used for
1289 * the recheck procedure
1290 */
1291
1292 while (length > 0) {
1293 sublen = min_t(u64, length, PAGE_SIZE);
1294 mapped_length = sublen;
1295 bbio = NULL;
1296
1297 /*
1298 * with a length of PAGE_SIZE, each returned stripe
1299 * represents one mirror
1300 */
1301 btrfs_bio_counter_inc_blocked(fs_info);
1302 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS,
1303 logical, &mapped_length, &bbio);
1304 if (ret || !bbio || mapped_length < sublen) {
1305 btrfs_put_bbio(bbio);
1306 btrfs_bio_counter_dec(fs_info);
1307 return -EIO;
1308 }
1309
1310 recover = kzalloc(sizeof(struct scrub_recover), GFP_NOFS);
1311 if (!recover) {
1312 btrfs_put_bbio(bbio);
1313 btrfs_bio_counter_dec(fs_info);
1314 return -ENOMEM;
1315 }
1316
1317 refcount_set(&recover->refs, 1);
1318 recover->bbio = bbio;
1319 recover->map_length = mapped_length;
1320
1321 BUG_ON(page_index >= SCRUB_MAX_PAGES_PER_BLOCK);
1322
1323 nmirrors = min(scrub_nr_raid_mirrors(bbio), BTRFS_MAX_MIRRORS);
1324
1325 for (mirror_index = 0; mirror_index < nmirrors;
1326 mirror_index++) {
1327 struct scrub_block *sblock;
1328 struct scrub_page *page;
1329
1330 sblock = sblocks_for_recheck + mirror_index;
1331 sblock->sctx = sctx;
1332
1333 page = kzalloc(sizeof(*page), GFP_NOFS);
1334 if (!page) {
1335 leave_nomem:
1336 spin_lock(&sctx->stat_lock);
1337 sctx->stat.malloc_errors++;
1338 spin_unlock(&sctx->stat_lock);
1339 scrub_put_recover(fs_info, recover);
1340 return -ENOMEM;
1341 }
1342 scrub_page_get(page);
1343 sblock->pagev[page_index] = page;
1344 page->sblock = sblock;
1345 page->flags = flags;
1346 page->generation = generation;
1347 page->logical = logical;
1348 page->have_csum = have_csum;
1349 if (have_csum)
1350 memcpy(page->csum,
1351 original_sblock->pagev[0]->csum,
1352 sctx->csum_size);
1353
1354 scrub_stripe_index_and_offset(logical,
1355 bbio->map_type,
1356 bbio->raid_map,
1357 mapped_length,
1358 bbio->num_stripes -
1359 bbio->num_tgtdevs,
1360 mirror_index,
1361 &stripe_index,
1362 &stripe_offset);
1363 page->physical = bbio->stripes[stripe_index].physical +
1364 stripe_offset;
1365 page->dev = bbio->stripes[stripe_index].dev;
1366
1367 BUG_ON(page_index >= original_sblock->page_count);
1368 page->physical_for_dev_replace =
1369 original_sblock->pagev[page_index]->
1370 physical_for_dev_replace;
1371 /* for missing devices, dev->bdev is NULL */
1372 page->mirror_num = mirror_index + 1;
1373 sblock->page_count++;
1374 page->page = alloc_page(GFP_NOFS);
1375 if (!page->page)
1376 goto leave_nomem;
1377
1378 scrub_get_recover(recover);
1379 page->recover = recover;
1380 }
1381 scrub_put_recover(fs_info, recover);
1382 length -= sublen;
1383 logical += sublen;
1384 page_index++;
1385 }
1386
1387 return 0;
1388 }
1389
1390 static void scrub_bio_wait_endio(struct bio *bio)
1391 {
1392 complete(bio->bi_private);
1393 }
1394
1395 static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
1396 struct bio *bio,
1397 struct scrub_page *page)
1398 {
1399 DECLARE_COMPLETION_ONSTACK(done);
1400 int ret;
1401 int mirror_num;
1402
1403 bio->bi_iter.bi_sector = page->logical >> 9;
1404 bio->bi_private = &done;
1405 bio->bi_end_io = scrub_bio_wait_endio;
1406
1407 mirror_num = page->sblock->pagev[0]->mirror_num;
1408 ret = raid56_parity_recover(fs_info, bio, page->recover->bbio,
1409 page->recover->map_length,
1410 mirror_num, 0);
1411 if (ret)
1412 return ret;
1413
1414 wait_for_completion_io(&done);
1415 return blk_status_to_errno(bio->bi_status);
1416 }
1417
1418 static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info,
1419 struct scrub_block *sblock)
1420 {
1421 struct scrub_page *first_page = sblock->pagev[0];
1422 struct bio *bio;
1423 int page_num;
1424
1425 /* All pages in sblock belong to the same stripe on the same device. */
1426 ASSERT(first_page->dev);
1427 if (!first_page->dev->bdev)
1428 goto out;
1429
1430 bio = btrfs_io_bio_alloc(BIO_MAX_PAGES);
1431 bio_set_dev(bio, first_page->dev->bdev);
1432
1433 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1434 struct scrub_page *page = sblock->pagev[page_num];
1435
1436 WARN_ON(!page->page);
1437 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1438 }
1439
1440 if (scrub_submit_raid56_bio_wait(fs_info, bio, first_page)) {
1441 bio_put(bio);
1442 goto out;
1443 }
1444
1445 bio_put(bio);
1446
1447 scrub_recheck_block_checksum(sblock);
1448
1449 return;
1450 out:
1451 for (page_num = 0; page_num < sblock->page_count; page_num++)
1452 sblock->pagev[page_num]->io_error = 1;
1453
1454 sblock->no_io_error_seen = 0;
1455 }
1456
1457 /*
1458 * this function will check the on disk data for checksum errors, header
1459 * errors and read I/O errors. If any I/O errors happen, the exact pages
1460 * which are errored are marked as being bad. The goal is to enable scrub
1461 * to take those pages that are not errored from all the mirrors so that
1462 * the pages that are errored in the just handled mirror can be repaired.
1463 */
1464 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
1465 struct scrub_block *sblock,
1466 int retry_failed_mirror)
1467 {
1468 int page_num;
1469
1470 sblock->no_io_error_seen = 1;
1471
1472 /* short cut for raid56 */
1473 if (!retry_failed_mirror && scrub_is_page_on_raid56(sblock->pagev[0]))
1474 return scrub_recheck_block_on_raid56(fs_info, sblock);
1475
1476 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1477 struct bio *bio;
1478 struct scrub_page *page = sblock->pagev[page_num];
1479
1480 if (page->dev->bdev == NULL) {
1481 page->io_error = 1;
1482 sblock->no_io_error_seen = 0;
1483 continue;
1484 }
1485
1486 WARN_ON(!page->page);
1487 bio = btrfs_io_bio_alloc(1);
1488 bio_set_dev(bio, page->dev->bdev);
1489
1490 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1491 bio->bi_iter.bi_sector = page->physical >> 9;
1492 bio->bi_opf = REQ_OP_READ;
1493
1494 if (btrfsic_submit_bio_wait(bio)) {
1495 page->io_error = 1;
1496 sblock->no_io_error_seen = 0;
1497 }
1498
1499 bio_put(bio);
1500 }
1501
1502 if (sblock->no_io_error_seen)
1503 scrub_recheck_block_checksum(sblock);
1504 }
1505
1506 static inline int scrub_check_fsid(u8 fsid[],
1507 struct scrub_page *spage)
1508 {
1509 struct btrfs_fs_devices *fs_devices = spage->dev->fs_devices;
1510 int ret;
1511
1512 ret = memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1513 return !ret;
1514 }
1515
1516 static void scrub_recheck_block_checksum(struct scrub_block *sblock)
1517 {
1518 sblock->header_error = 0;
1519 sblock->checksum_error = 0;
1520 sblock->generation_error = 0;
1521
1522 if (sblock->pagev[0]->flags & BTRFS_EXTENT_FLAG_DATA)
1523 scrub_checksum_data(sblock);
1524 else
1525 scrub_checksum_tree_block(sblock);
1526 }
1527
1528 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1529 struct scrub_block *sblock_good)
1530 {
1531 int page_num;
1532 int ret = 0;
1533
1534 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1535 int ret_sub;
1536
1537 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1538 sblock_good,
1539 page_num, 1);
1540 if (ret_sub)
1541 ret = ret_sub;
1542 }
1543
1544 return ret;
1545 }
1546
1547 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1548 struct scrub_block *sblock_good,
1549 int page_num, int force_write)
1550 {
1551 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1552 struct scrub_page *page_good = sblock_good->pagev[page_num];
1553 struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info;
1554
1555 BUG_ON(page_bad->page == NULL);
1556 BUG_ON(page_good->page == NULL);
1557 if (force_write || sblock_bad->header_error ||
1558 sblock_bad->checksum_error || page_bad->io_error) {
1559 struct bio *bio;
1560 int ret;
1561
1562 if (!page_bad->dev->bdev) {
1563 btrfs_warn_rl(fs_info,
1564 "scrub_repair_page_from_good_copy(bdev == NULL) is unexpected");
1565 return -EIO;
1566 }
1567
1568 bio = btrfs_io_bio_alloc(1);
1569 bio_set_dev(bio, page_bad->dev->bdev);
1570 bio->bi_iter.bi_sector = page_bad->physical >> 9;
1571 bio->bi_opf = REQ_OP_WRITE;
1572
1573 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1574 if (PAGE_SIZE != ret) {
1575 bio_put(bio);
1576 return -EIO;
1577 }
1578
1579 if (btrfsic_submit_bio_wait(bio)) {
1580 btrfs_dev_stat_inc_and_print(page_bad->dev,
1581 BTRFS_DEV_STAT_WRITE_ERRS);
1582 atomic64_inc(&fs_info->dev_replace.num_write_errors);
1583 bio_put(bio);
1584 return -EIO;
1585 }
1586 bio_put(bio);
1587 }
1588
1589 return 0;
1590 }
1591
1592 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
1593 {
1594 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
1595 int page_num;
1596
1597 /*
1598 * This block is used for the check of the parity on the source device,
1599 * so the data needn't be written into the destination device.
1600 */
1601 if (sblock->sparity)
1602 return;
1603
1604 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1605 int ret;
1606
1607 ret = scrub_write_page_to_dev_replace(sblock, page_num);
1608 if (ret)
1609 atomic64_inc(&fs_info->dev_replace.num_write_errors);
1610 }
1611 }
1612
1613 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
1614 int page_num)
1615 {
1616 struct scrub_page *spage = sblock->pagev[page_num];
1617
1618 BUG_ON(spage->page == NULL);
1619 if (spage->io_error) {
1620 void *mapped_buffer = kmap_atomic(spage->page);
1621
1622 clear_page(mapped_buffer);
1623 flush_dcache_page(spage->page);
1624 kunmap_atomic(mapped_buffer);
1625 }
1626 return scrub_add_page_to_wr_bio(sblock->sctx, spage);
1627 }
1628
1629 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
1630 struct scrub_page *spage)
1631 {
1632 struct scrub_bio *sbio;
1633 int ret;
1634
1635 mutex_lock(&sctx->wr_lock);
1636 again:
1637 if (!sctx->wr_curr_bio) {
1638 sctx->wr_curr_bio = kzalloc(sizeof(*sctx->wr_curr_bio),
1639 GFP_KERNEL);
1640 if (!sctx->wr_curr_bio) {
1641 mutex_unlock(&sctx->wr_lock);
1642 return -ENOMEM;
1643 }
1644 sctx->wr_curr_bio->sctx = sctx;
1645 sctx->wr_curr_bio->page_count = 0;
1646 }
1647 sbio = sctx->wr_curr_bio;
1648 if (sbio->page_count == 0) {
1649 struct bio *bio;
1650
1651 sbio->physical = spage->physical_for_dev_replace;
1652 sbio->logical = spage->logical;
1653 sbio->dev = sctx->wr_tgtdev;
1654 bio = sbio->bio;
1655 if (!bio) {
1656 bio = btrfs_io_bio_alloc(sctx->pages_per_wr_bio);
1657 sbio->bio = bio;
1658 }
1659
1660 bio->bi_private = sbio;
1661 bio->bi_end_io = scrub_wr_bio_end_io;
1662 bio_set_dev(bio, sbio->dev->bdev);
1663 bio->bi_iter.bi_sector = sbio->physical >> 9;
1664 bio->bi_opf = REQ_OP_WRITE;
1665 sbio->status = 0;
1666 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1667 spage->physical_for_dev_replace ||
1668 sbio->logical + sbio->page_count * PAGE_SIZE !=
1669 spage->logical) {
1670 scrub_wr_submit(sctx);
1671 goto again;
1672 }
1673
1674 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1675 if (ret != PAGE_SIZE) {
1676 if (sbio->page_count < 1) {
1677 bio_put(sbio->bio);
1678 sbio->bio = NULL;
1679 mutex_unlock(&sctx->wr_lock);
1680 return -EIO;
1681 }
1682 scrub_wr_submit(sctx);
1683 goto again;
1684 }
1685
1686 sbio->pagev[sbio->page_count] = spage;
1687 scrub_page_get(spage);
1688 sbio->page_count++;
1689 if (sbio->page_count == sctx->pages_per_wr_bio)
1690 scrub_wr_submit(sctx);
1691 mutex_unlock(&sctx->wr_lock);
1692
1693 return 0;
1694 }
1695
1696 static void scrub_wr_submit(struct scrub_ctx *sctx)
1697 {
1698 struct scrub_bio *sbio;
1699
1700 if (!sctx->wr_curr_bio)
1701 return;
1702
1703 sbio = sctx->wr_curr_bio;
1704 sctx->wr_curr_bio = NULL;
1705 WARN_ON(!sbio->bio->bi_disk);
1706 scrub_pending_bio_inc(sctx);
1707 /* process all writes in a single worker thread. Then the block layer
1708 * orders the requests before sending them to the driver which
1709 * doubled the write performance on spinning disks when measured
1710 * with Linux 3.5 */
1711 btrfsic_submit_bio(sbio->bio);
1712 }
1713
1714 static void scrub_wr_bio_end_io(struct bio *bio)
1715 {
1716 struct scrub_bio *sbio = bio->bi_private;
1717 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
1718
1719 sbio->status = bio->bi_status;
1720 sbio->bio = bio;
1721
1722 btrfs_init_work(&sbio->work, scrub_wr_bio_end_io_worker, NULL, NULL);
1723 btrfs_queue_work(fs_info->scrub_wr_completion_workers, &sbio->work);
1724 }
1725
1726 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work)
1727 {
1728 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1729 struct scrub_ctx *sctx = sbio->sctx;
1730 int i;
1731
1732 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO);
1733 if (sbio->status) {
1734 struct btrfs_dev_replace *dev_replace =
1735 &sbio->sctx->fs_info->dev_replace;
1736
1737 for (i = 0; i < sbio->page_count; i++) {
1738 struct scrub_page *spage = sbio->pagev[i];
1739
1740 spage->io_error = 1;
1741 atomic64_inc(&dev_replace->num_write_errors);
1742 }
1743 }
1744
1745 for (i = 0; i < sbio->page_count; i++)
1746 scrub_page_put(sbio->pagev[i]);
1747
1748 bio_put(sbio->bio);
1749 kfree(sbio);
1750 scrub_pending_bio_dec(sctx);
1751 }
1752
1753 static int scrub_checksum(struct scrub_block *sblock)
1754 {
1755 u64 flags;
1756 int ret;
1757
1758 /*
1759 * No need to initialize these stats currently,
1760 * because this function only use return value
1761 * instead of these stats value.
1762 *
1763 * Todo:
1764 * always use stats
1765 */
1766 sblock->header_error = 0;
1767 sblock->generation_error = 0;
1768 sblock->checksum_error = 0;
1769
1770 WARN_ON(sblock->page_count < 1);
1771 flags = sblock->pagev[0]->flags;
1772 ret = 0;
1773 if (flags & BTRFS_EXTENT_FLAG_DATA)
1774 ret = scrub_checksum_data(sblock);
1775 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1776 ret = scrub_checksum_tree_block(sblock);
1777 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1778 (void)scrub_checksum_super(sblock);
1779 else
1780 WARN_ON(1);
1781 if (ret)
1782 scrub_handle_errored_block(sblock);
1783
1784 return ret;
1785 }
1786
1787 static int scrub_checksum_data(struct scrub_block *sblock)
1788 {
1789 struct scrub_ctx *sctx = sblock->sctx;
1790 struct btrfs_fs_info *fs_info = sctx->fs_info;
1791 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
1792 u8 csum[BTRFS_CSUM_SIZE];
1793 u8 *on_disk_csum;
1794 struct page *page;
1795 void *buffer;
1796 u64 len;
1797 int index;
1798
1799 BUG_ON(sblock->page_count < 1);
1800 if (!sblock->pagev[0]->have_csum)
1801 return 0;
1802
1803 shash->tfm = fs_info->csum_shash;
1804 crypto_shash_init(shash);
1805
1806 on_disk_csum = sblock->pagev[0]->csum;
1807 page = sblock->pagev[0]->page;
1808 buffer = kmap_atomic(page);
1809
1810 len = sctx->fs_info->sectorsize;
1811 index = 0;
1812 for (;;) {
1813 u64 l = min_t(u64, len, PAGE_SIZE);
1814
1815 crypto_shash_update(shash, buffer, l);
1816 kunmap_atomic(buffer);
1817 len -= l;
1818 if (len == 0)
1819 break;
1820 index++;
1821 BUG_ON(index >= sblock->page_count);
1822 BUG_ON(!sblock->pagev[index]->page);
1823 page = sblock->pagev[index]->page;
1824 buffer = kmap_atomic(page);
1825 }
1826
1827 crypto_shash_final(shash, csum);
1828 if (memcmp(csum, on_disk_csum, sctx->csum_size))
1829 sblock->checksum_error = 1;
1830
1831 return sblock->checksum_error;
1832 }
1833
1834 static int scrub_checksum_tree_block(struct scrub_block *sblock)
1835 {
1836 struct scrub_ctx *sctx = sblock->sctx;
1837 struct btrfs_header *h;
1838 struct btrfs_fs_info *fs_info = sctx->fs_info;
1839 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
1840 u8 calculated_csum[BTRFS_CSUM_SIZE];
1841 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1842 struct page *page;
1843 void *mapped_buffer;
1844 u64 mapped_size;
1845 void *p;
1846 u64 len;
1847 int index;
1848
1849 shash->tfm = fs_info->csum_shash;
1850 crypto_shash_init(shash);
1851
1852 BUG_ON(sblock->page_count < 1);
1853 page = sblock->pagev[0]->page;
1854 mapped_buffer = kmap_atomic(page);
1855 h = (struct btrfs_header *)mapped_buffer;
1856 memcpy(on_disk_csum, h->csum, sctx->csum_size);
1857
1858 /*
1859 * we don't use the getter functions here, as we
1860 * a) don't have an extent buffer and
1861 * b) the page is already kmapped
1862 */
1863 if (sblock->pagev[0]->logical != btrfs_stack_header_bytenr(h))
1864 sblock->header_error = 1;
1865
1866 if (sblock->pagev[0]->generation != btrfs_stack_header_generation(h)) {
1867 sblock->header_error = 1;
1868 sblock->generation_error = 1;
1869 }
1870
1871 if (!scrub_check_fsid(h->fsid, sblock->pagev[0]))
1872 sblock->header_error = 1;
1873
1874 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1875 BTRFS_UUID_SIZE))
1876 sblock->header_error = 1;
1877
1878 len = sctx->fs_info->nodesize - BTRFS_CSUM_SIZE;
1879 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1880 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1881 index = 0;
1882 for (;;) {
1883 u64 l = min_t(u64, len, mapped_size);
1884
1885 crypto_shash_update(shash, p, l);
1886 kunmap_atomic(mapped_buffer);
1887 len -= l;
1888 if (len == 0)
1889 break;
1890 index++;
1891 BUG_ON(index >= sblock->page_count);
1892 BUG_ON(!sblock->pagev[index]->page);
1893 page = sblock->pagev[index]->page;
1894 mapped_buffer = kmap_atomic(page);
1895 mapped_size = PAGE_SIZE;
1896 p = mapped_buffer;
1897 }
1898
1899 crypto_shash_final(shash, calculated_csum);
1900 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1901 sblock->checksum_error = 1;
1902
1903 return sblock->header_error || sblock->checksum_error;
1904 }
1905
1906 static int scrub_checksum_super(struct scrub_block *sblock)
1907 {
1908 struct btrfs_super_block *s;
1909 struct scrub_ctx *sctx = sblock->sctx;
1910 struct btrfs_fs_info *fs_info = sctx->fs_info;
1911 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
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 int fail_gen = 0;
1919 int fail_cor = 0;
1920 u64 len;
1921 int index;
1922
1923 shash->tfm = fs_info->csum_shash;
1924 crypto_shash_init(shash);
1925
1926 BUG_ON(sblock->page_count < 1);
1927 page = sblock->pagev[0]->page;
1928 mapped_buffer = kmap_atomic(page);
1929 s = (struct btrfs_super_block *)mapped_buffer;
1930 memcpy(on_disk_csum, s->csum, sctx->csum_size);
1931
1932 if (sblock->pagev[0]->logical != btrfs_super_bytenr(s))
1933 ++fail_cor;
1934
1935 if (sblock->pagev[0]->generation != btrfs_super_generation(s))
1936 ++fail_gen;
1937
1938 if (!scrub_check_fsid(s->fsid, sblock->pagev[0]))
1939 ++fail_cor;
1940
1941 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1942 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1943 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1944 index = 0;
1945 for (;;) {
1946 u64 l = min_t(u64, len, mapped_size);
1947
1948 crypto_shash_update(shash, p, l);
1949 kunmap_atomic(mapped_buffer);
1950 len -= l;
1951 if (len == 0)
1952 break;
1953 index++;
1954 BUG_ON(index >= sblock->page_count);
1955 BUG_ON(!sblock->pagev[index]->page);
1956 page = sblock->pagev[index]->page;
1957 mapped_buffer = kmap_atomic(page);
1958 mapped_size = PAGE_SIZE;
1959 p = mapped_buffer;
1960 }
1961
1962 crypto_shash_final(shash, calculated_csum);
1963 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1964 ++fail_cor;
1965
1966 if (fail_cor + fail_gen) {
1967 /*
1968 * if we find an error in a super block, we just report it.
1969 * They will get written with the next transaction commit
1970 * anyway
1971 */
1972 spin_lock(&sctx->stat_lock);
1973 ++sctx->stat.super_errors;
1974 spin_unlock(&sctx->stat_lock);
1975 if (fail_cor)
1976 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1977 BTRFS_DEV_STAT_CORRUPTION_ERRS);
1978 else
1979 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1980 BTRFS_DEV_STAT_GENERATION_ERRS);
1981 }
1982
1983 return fail_cor + fail_gen;
1984 }
1985
1986 static void scrub_block_get(struct scrub_block *sblock)
1987 {
1988 refcount_inc(&sblock->refs);
1989 }
1990
1991 static void scrub_block_put(struct scrub_block *sblock)
1992 {
1993 if (refcount_dec_and_test(&sblock->refs)) {
1994 int i;
1995
1996 if (sblock->sparity)
1997 scrub_parity_put(sblock->sparity);
1998
1999 for (i = 0; i < sblock->page_count; i++)
2000 scrub_page_put(sblock->pagev[i]);
2001 kfree(sblock);
2002 }
2003 }
2004
2005 static void scrub_page_get(struct scrub_page *spage)
2006 {
2007 atomic_inc(&spage->refs);
2008 }
2009
2010 static void scrub_page_put(struct scrub_page *spage)
2011 {
2012 if (atomic_dec_and_test(&spage->refs)) {
2013 if (spage->page)
2014 __free_page(spage->page);
2015 kfree(spage);
2016 }
2017 }
2018
2019 static void scrub_submit(struct scrub_ctx *sctx)
2020 {
2021 struct scrub_bio *sbio;
2022
2023 if (sctx->curr == -1)
2024 return;
2025
2026 sbio = sctx->bios[sctx->curr];
2027 sctx->curr = -1;
2028 scrub_pending_bio_inc(sctx);
2029 btrfsic_submit_bio(sbio->bio);
2030 }
2031
2032 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
2033 struct scrub_page *spage)
2034 {
2035 struct scrub_block *sblock = spage->sblock;
2036 struct scrub_bio *sbio;
2037 int ret;
2038
2039 again:
2040 /*
2041 * grab a fresh bio or wait for one to become available
2042 */
2043 while (sctx->curr == -1) {
2044 spin_lock(&sctx->list_lock);
2045 sctx->curr = sctx->first_free;
2046 if (sctx->curr != -1) {
2047 sctx->first_free = sctx->bios[sctx->curr]->next_free;
2048 sctx->bios[sctx->curr]->next_free = -1;
2049 sctx->bios[sctx->curr]->page_count = 0;
2050 spin_unlock(&sctx->list_lock);
2051 } else {
2052 spin_unlock(&sctx->list_lock);
2053 wait_event(sctx->list_wait, sctx->first_free != -1);
2054 }
2055 }
2056 sbio = sctx->bios[sctx->curr];
2057 if (sbio->page_count == 0) {
2058 struct bio *bio;
2059
2060 sbio->physical = spage->physical;
2061 sbio->logical = spage->logical;
2062 sbio->dev = spage->dev;
2063 bio = sbio->bio;
2064 if (!bio) {
2065 bio = btrfs_io_bio_alloc(sctx->pages_per_rd_bio);
2066 sbio->bio = bio;
2067 }
2068
2069 bio->bi_private = sbio;
2070 bio->bi_end_io = scrub_bio_end_io;
2071 bio_set_dev(bio, sbio->dev->bdev);
2072 bio->bi_iter.bi_sector = sbio->physical >> 9;
2073 bio->bi_opf = REQ_OP_READ;
2074 sbio->status = 0;
2075 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
2076 spage->physical ||
2077 sbio->logical + sbio->page_count * PAGE_SIZE !=
2078 spage->logical ||
2079 sbio->dev != spage->dev) {
2080 scrub_submit(sctx);
2081 goto again;
2082 }
2083
2084 sbio->pagev[sbio->page_count] = spage;
2085 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
2086 if (ret != PAGE_SIZE) {
2087 if (sbio->page_count < 1) {
2088 bio_put(sbio->bio);
2089 sbio->bio = NULL;
2090 return -EIO;
2091 }
2092 scrub_submit(sctx);
2093 goto again;
2094 }
2095
2096 scrub_block_get(sblock); /* one for the page added to the bio */
2097 atomic_inc(&sblock->outstanding_pages);
2098 sbio->page_count++;
2099 if (sbio->page_count == sctx->pages_per_rd_bio)
2100 scrub_submit(sctx);
2101
2102 return 0;
2103 }
2104
2105 static void scrub_missing_raid56_end_io(struct bio *bio)
2106 {
2107 struct scrub_block *sblock = bio->bi_private;
2108 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
2109
2110 if (bio->bi_status)
2111 sblock->no_io_error_seen = 0;
2112
2113 bio_put(bio);
2114
2115 btrfs_queue_work(fs_info->scrub_workers, &sblock->work);
2116 }
2117
2118 static void scrub_missing_raid56_worker(struct btrfs_work *work)
2119 {
2120 struct scrub_block *sblock = container_of(work, struct scrub_block, work);
2121 struct scrub_ctx *sctx = sblock->sctx;
2122 struct btrfs_fs_info *fs_info = sctx->fs_info;
2123 u64 logical;
2124 struct btrfs_device *dev;
2125
2126 logical = sblock->pagev[0]->logical;
2127 dev = sblock->pagev[0]->dev;
2128
2129 if (sblock->no_io_error_seen)
2130 scrub_recheck_block_checksum(sblock);
2131
2132 if (!sblock->no_io_error_seen) {
2133 spin_lock(&sctx->stat_lock);
2134 sctx->stat.read_errors++;
2135 spin_unlock(&sctx->stat_lock);
2136 btrfs_err_rl_in_rcu(fs_info,
2137 "IO error rebuilding logical %llu for dev %s",
2138 logical, rcu_str_deref(dev->name));
2139 } else if (sblock->header_error || sblock->checksum_error) {
2140 spin_lock(&sctx->stat_lock);
2141 sctx->stat.uncorrectable_errors++;
2142 spin_unlock(&sctx->stat_lock);
2143 btrfs_err_rl_in_rcu(fs_info,
2144 "failed to rebuild valid logical %llu for dev %s",
2145 logical, rcu_str_deref(dev->name));
2146 } else {
2147 scrub_write_block_to_dev_replace(sblock);
2148 }
2149
2150 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2151 mutex_lock(&sctx->wr_lock);
2152 scrub_wr_submit(sctx);
2153 mutex_unlock(&sctx->wr_lock);
2154 }
2155
2156 scrub_block_put(sblock);
2157 scrub_pending_bio_dec(sctx);
2158 }
2159
2160 static void scrub_missing_raid56_pages(struct scrub_block *sblock)
2161 {
2162 struct scrub_ctx *sctx = sblock->sctx;
2163 struct btrfs_fs_info *fs_info = sctx->fs_info;
2164 u64 length = sblock->page_count * PAGE_SIZE;
2165 u64 logical = sblock->pagev[0]->logical;
2166 struct btrfs_bio *bbio = NULL;
2167 struct bio *bio;
2168 struct btrfs_raid_bio *rbio;
2169 int ret;
2170 int i;
2171
2172 btrfs_bio_counter_inc_blocked(fs_info);
2173 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
2174 &length, &bbio);
2175 if (ret || !bbio || !bbio->raid_map)
2176 goto bbio_out;
2177
2178 if (WARN_ON(!sctx->is_dev_replace ||
2179 !(bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK))) {
2180 /*
2181 * We shouldn't be scrubbing a missing device. Even for dev
2182 * replace, we should only get here for RAID 5/6. We either
2183 * managed to mount something with no mirrors remaining or
2184 * there's a bug in scrub_remap_extent()/btrfs_map_block().
2185 */
2186 goto bbio_out;
2187 }
2188
2189 bio = btrfs_io_bio_alloc(0);
2190 bio->bi_iter.bi_sector = logical >> 9;
2191 bio->bi_private = sblock;
2192 bio->bi_end_io = scrub_missing_raid56_end_io;
2193
2194 rbio = raid56_alloc_missing_rbio(fs_info, bio, bbio, length);
2195 if (!rbio)
2196 goto rbio_out;
2197
2198 for (i = 0; i < sblock->page_count; i++) {
2199 struct scrub_page *spage = sblock->pagev[i];
2200
2201 raid56_add_scrub_pages(rbio, spage->page, spage->logical);
2202 }
2203
2204 btrfs_init_work(&sblock->work, scrub_missing_raid56_worker, NULL, NULL);
2205 scrub_block_get(sblock);
2206 scrub_pending_bio_inc(sctx);
2207 raid56_submit_missing_rbio(rbio);
2208 return;
2209
2210 rbio_out:
2211 bio_put(bio);
2212 bbio_out:
2213 btrfs_bio_counter_dec(fs_info);
2214 btrfs_put_bbio(bbio);
2215 spin_lock(&sctx->stat_lock);
2216 sctx->stat.malloc_errors++;
2217 spin_unlock(&sctx->stat_lock);
2218 }
2219
2220 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
2221 u64 physical, struct btrfs_device *dev, u64 flags,
2222 u64 gen, int mirror_num, u8 *csum, int force,
2223 u64 physical_for_dev_replace)
2224 {
2225 struct scrub_block *sblock;
2226 int index;
2227
2228 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2229 if (!sblock) {
2230 spin_lock(&sctx->stat_lock);
2231 sctx->stat.malloc_errors++;
2232 spin_unlock(&sctx->stat_lock);
2233 return -ENOMEM;
2234 }
2235
2236 /* one ref inside this function, plus one for each page added to
2237 * a bio later on */
2238 refcount_set(&sblock->refs, 1);
2239 sblock->sctx = sctx;
2240 sblock->no_io_error_seen = 1;
2241
2242 for (index = 0; len > 0; index++) {
2243 struct scrub_page *spage;
2244 u64 l = min_t(u64, len, PAGE_SIZE);
2245
2246 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2247 if (!spage) {
2248 leave_nomem:
2249 spin_lock(&sctx->stat_lock);
2250 sctx->stat.malloc_errors++;
2251 spin_unlock(&sctx->stat_lock);
2252 scrub_block_put(sblock);
2253 return -ENOMEM;
2254 }
2255 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2256 scrub_page_get(spage);
2257 sblock->pagev[index] = spage;
2258 spage->sblock = sblock;
2259 spage->dev = dev;
2260 spage->flags = flags;
2261 spage->generation = gen;
2262 spage->logical = logical;
2263 spage->physical = physical;
2264 spage->physical_for_dev_replace = physical_for_dev_replace;
2265 spage->mirror_num = mirror_num;
2266 if (csum) {
2267 spage->have_csum = 1;
2268 memcpy(spage->csum, csum, sctx->csum_size);
2269 } else {
2270 spage->have_csum = 0;
2271 }
2272 sblock->page_count++;
2273 spage->page = alloc_page(GFP_KERNEL);
2274 if (!spage->page)
2275 goto leave_nomem;
2276 len -= l;
2277 logical += l;
2278 physical += l;
2279 physical_for_dev_replace += l;
2280 }
2281
2282 WARN_ON(sblock->page_count == 0);
2283 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2284 /*
2285 * This case should only be hit for RAID 5/6 device replace. See
2286 * the comment in scrub_missing_raid56_pages() for details.
2287 */
2288 scrub_missing_raid56_pages(sblock);
2289 } else {
2290 for (index = 0; index < sblock->page_count; index++) {
2291 struct scrub_page *spage = sblock->pagev[index];
2292 int ret;
2293
2294 ret = scrub_add_page_to_rd_bio(sctx, spage);
2295 if (ret) {
2296 scrub_block_put(sblock);
2297 return ret;
2298 }
2299 }
2300
2301 if (force)
2302 scrub_submit(sctx);
2303 }
2304
2305 /* last one frees, either here or in bio completion for last page */
2306 scrub_block_put(sblock);
2307 return 0;
2308 }
2309
2310 static void scrub_bio_end_io(struct bio *bio)
2311 {
2312 struct scrub_bio *sbio = bio->bi_private;
2313 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
2314
2315 sbio->status = bio->bi_status;
2316 sbio->bio = bio;
2317
2318 btrfs_queue_work(fs_info->scrub_workers, &sbio->work);
2319 }
2320
2321 static void scrub_bio_end_io_worker(struct btrfs_work *work)
2322 {
2323 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
2324 struct scrub_ctx *sctx = sbio->sctx;
2325 int i;
2326
2327 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO);
2328 if (sbio->status) {
2329 for (i = 0; i < sbio->page_count; i++) {
2330 struct scrub_page *spage = sbio->pagev[i];
2331
2332 spage->io_error = 1;
2333 spage->sblock->no_io_error_seen = 0;
2334 }
2335 }
2336
2337 /* now complete the scrub_block items that have all pages completed */
2338 for (i = 0; i < sbio->page_count; i++) {
2339 struct scrub_page *spage = sbio->pagev[i];
2340 struct scrub_block *sblock = spage->sblock;
2341
2342 if (atomic_dec_and_test(&sblock->outstanding_pages))
2343 scrub_block_complete(sblock);
2344 scrub_block_put(sblock);
2345 }
2346
2347 bio_put(sbio->bio);
2348 sbio->bio = NULL;
2349 spin_lock(&sctx->list_lock);
2350 sbio->next_free = sctx->first_free;
2351 sctx->first_free = sbio->index;
2352 spin_unlock(&sctx->list_lock);
2353
2354 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2355 mutex_lock(&sctx->wr_lock);
2356 scrub_wr_submit(sctx);
2357 mutex_unlock(&sctx->wr_lock);
2358 }
2359
2360 scrub_pending_bio_dec(sctx);
2361 }
2362
2363 static inline void __scrub_mark_bitmap(struct scrub_parity *sparity,
2364 unsigned long *bitmap,
2365 u64 start, u64 len)
2366 {
2367 u64 offset;
2368 u64 nsectors64;
2369 u32 nsectors;
2370 int sectorsize = sparity->sctx->fs_info->sectorsize;
2371
2372 if (len >= sparity->stripe_len) {
2373 bitmap_set(bitmap, 0, sparity->nsectors);
2374 return;
2375 }
2376
2377 start -= sparity->logic_start;
2378 start = div64_u64_rem(start, sparity->stripe_len, &offset);
2379 offset = div_u64(offset, sectorsize);
2380 nsectors64 = div_u64(len, sectorsize);
2381
2382 ASSERT(nsectors64 < UINT_MAX);
2383 nsectors = (u32)nsectors64;
2384
2385 if (offset + nsectors <= sparity->nsectors) {
2386 bitmap_set(bitmap, offset, nsectors);
2387 return;
2388 }
2389
2390 bitmap_set(bitmap, offset, sparity->nsectors - offset);
2391 bitmap_set(bitmap, 0, nsectors - (sparity->nsectors - offset));
2392 }
2393
2394 static inline void scrub_parity_mark_sectors_error(struct scrub_parity *sparity,
2395 u64 start, u64 len)
2396 {
2397 __scrub_mark_bitmap(sparity, sparity->ebitmap, start, len);
2398 }
2399
2400 static inline void scrub_parity_mark_sectors_data(struct scrub_parity *sparity,
2401 u64 start, u64 len)
2402 {
2403 __scrub_mark_bitmap(sparity, sparity->dbitmap, start, len);
2404 }
2405
2406 static void scrub_block_complete(struct scrub_block *sblock)
2407 {
2408 int corrupted = 0;
2409
2410 if (!sblock->no_io_error_seen) {
2411 corrupted = 1;
2412 scrub_handle_errored_block(sblock);
2413 } else {
2414 /*
2415 * if has checksum error, write via repair mechanism in
2416 * dev replace case, otherwise write here in dev replace
2417 * case.
2418 */
2419 corrupted = scrub_checksum(sblock);
2420 if (!corrupted && sblock->sctx->is_dev_replace)
2421 scrub_write_block_to_dev_replace(sblock);
2422 }
2423
2424 if (sblock->sparity && corrupted && !sblock->data_corrected) {
2425 u64 start = sblock->pagev[0]->logical;
2426 u64 end = sblock->pagev[sblock->page_count - 1]->logical +
2427 PAGE_SIZE;
2428
2429 scrub_parity_mark_sectors_error(sblock->sparity,
2430 start, end - start);
2431 }
2432 }
2433
2434 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum)
2435 {
2436 struct btrfs_ordered_sum *sum = NULL;
2437 unsigned long index;
2438 unsigned long num_sectors;
2439
2440 while (!list_empty(&sctx->csum_list)) {
2441 sum = list_first_entry(&sctx->csum_list,
2442 struct btrfs_ordered_sum, list);
2443 if (sum->bytenr > logical)
2444 return 0;
2445 if (sum->bytenr + sum->len > logical)
2446 break;
2447
2448 ++sctx->stat.csum_discards;
2449 list_del(&sum->list);
2450 kfree(sum);
2451 sum = NULL;
2452 }
2453 if (!sum)
2454 return 0;
2455
2456 index = div_u64(logical - sum->bytenr, sctx->fs_info->sectorsize);
2457 ASSERT(index < UINT_MAX);
2458
2459 num_sectors = sum->len / sctx->fs_info->sectorsize;
2460 memcpy(csum, sum->sums + index * sctx->csum_size, sctx->csum_size);
2461 if (index == num_sectors - 1) {
2462 list_del(&sum->list);
2463 kfree(sum);
2464 }
2465 return 1;
2466 }
2467
2468 /* scrub extent tries to collect up to 64 kB for each bio */
2469 static int scrub_extent(struct scrub_ctx *sctx, struct map_lookup *map,
2470 u64 logical, u64 len,
2471 u64 physical, struct btrfs_device *dev, u64 flags,
2472 u64 gen, int mirror_num, u64 physical_for_dev_replace)
2473 {
2474 int ret;
2475 u8 csum[BTRFS_CSUM_SIZE];
2476 u32 blocksize;
2477
2478 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2479 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2480 blocksize = map->stripe_len;
2481 else
2482 blocksize = sctx->fs_info->sectorsize;
2483 spin_lock(&sctx->stat_lock);
2484 sctx->stat.data_extents_scrubbed++;
2485 sctx->stat.data_bytes_scrubbed += len;
2486 spin_unlock(&sctx->stat_lock);
2487 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2488 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2489 blocksize = map->stripe_len;
2490 else
2491 blocksize = sctx->fs_info->nodesize;
2492 spin_lock(&sctx->stat_lock);
2493 sctx->stat.tree_extents_scrubbed++;
2494 sctx->stat.tree_bytes_scrubbed += len;
2495 spin_unlock(&sctx->stat_lock);
2496 } else {
2497 blocksize = sctx->fs_info->sectorsize;
2498 WARN_ON(1);
2499 }
2500
2501 while (len) {
2502 u64 l = min_t(u64, len, blocksize);
2503 int have_csum = 0;
2504
2505 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2506 /* push csums to sbio */
2507 have_csum = scrub_find_csum(sctx, logical, csum);
2508 if (have_csum == 0)
2509 ++sctx->stat.no_csum;
2510 }
2511 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen,
2512 mirror_num, have_csum ? csum : NULL, 0,
2513 physical_for_dev_replace);
2514 if (ret)
2515 return ret;
2516 len -= l;
2517 logical += l;
2518 physical += l;
2519 physical_for_dev_replace += l;
2520 }
2521 return 0;
2522 }
2523
2524 static int scrub_pages_for_parity(struct scrub_parity *sparity,
2525 u64 logical, u64 len,
2526 u64 physical, struct btrfs_device *dev,
2527 u64 flags, u64 gen, int mirror_num, u8 *csum)
2528 {
2529 struct scrub_ctx *sctx = sparity->sctx;
2530 struct scrub_block *sblock;
2531 int index;
2532
2533 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2534 if (!sblock) {
2535 spin_lock(&sctx->stat_lock);
2536 sctx->stat.malloc_errors++;
2537 spin_unlock(&sctx->stat_lock);
2538 return -ENOMEM;
2539 }
2540
2541 /* one ref inside this function, plus one for each page added to
2542 * a bio later on */
2543 refcount_set(&sblock->refs, 1);
2544 sblock->sctx = sctx;
2545 sblock->no_io_error_seen = 1;
2546 sblock->sparity = sparity;
2547 scrub_parity_get(sparity);
2548
2549 for (index = 0; len > 0; index++) {
2550 struct scrub_page *spage;
2551 u64 l = min_t(u64, len, PAGE_SIZE);
2552
2553 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2554 if (!spage) {
2555 leave_nomem:
2556 spin_lock(&sctx->stat_lock);
2557 sctx->stat.malloc_errors++;
2558 spin_unlock(&sctx->stat_lock);
2559 scrub_block_put(sblock);
2560 return -ENOMEM;
2561 }
2562 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2563 /* For scrub block */
2564 scrub_page_get(spage);
2565 sblock->pagev[index] = spage;
2566 /* For scrub parity */
2567 scrub_page_get(spage);
2568 list_add_tail(&spage->list, &sparity->spages);
2569 spage->sblock = sblock;
2570 spage->dev = dev;
2571 spage->flags = flags;
2572 spage->generation = gen;
2573 spage->logical = logical;
2574 spage->physical = physical;
2575 spage->mirror_num = mirror_num;
2576 if (csum) {
2577 spage->have_csum = 1;
2578 memcpy(spage->csum, csum, sctx->csum_size);
2579 } else {
2580 spage->have_csum = 0;
2581 }
2582 sblock->page_count++;
2583 spage->page = alloc_page(GFP_KERNEL);
2584 if (!spage->page)
2585 goto leave_nomem;
2586 len -= l;
2587 logical += l;
2588 physical += l;
2589 }
2590
2591 WARN_ON(sblock->page_count == 0);
2592 for (index = 0; index < sblock->page_count; index++) {
2593 struct scrub_page *spage = sblock->pagev[index];
2594 int ret;
2595
2596 ret = scrub_add_page_to_rd_bio(sctx, spage);
2597 if (ret) {
2598 scrub_block_put(sblock);
2599 return ret;
2600 }
2601 }
2602
2603 /* last one frees, either here or in bio completion for last page */
2604 scrub_block_put(sblock);
2605 return 0;
2606 }
2607
2608 static int scrub_extent_for_parity(struct scrub_parity *sparity,
2609 u64 logical, u64 len,
2610 u64 physical, struct btrfs_device *dev,
2611 u64 flags, u64 gen, int mirror_num)
2612 {
2613 struct scrub_ctx *sctx = sparity->sctx;
2614 int ret;
2615 u8 csum[BTRFS_CSUM_SIZE];
2616 u32 blocksize;
2617
2618 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2619 scrub_parity_mark_sectors_error(sparity, logical, len);
2620 return 0;
2621 }
2622
2623 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2624 blocksize = sparity->stripe_len;
2625 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2626 blocksize = sparity->stripe_len;
2627 } else {
2628 blocksize = sctx->fs_info->sectorsize;
2629 WARN_ON(1);
2630 }
2631
2632 while (len) {
2633 u64 l = min_t(u64, len, blocksize);
2634 int have_csum = 0;
2635
2636 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2637 /* push csums to sbio */
2638 have_csum = scrub_find_csum(sctx, logical, csum);
2639 if (have_csum == 0)
2640 goto skip;
2641 }
2642 ret = scrub_pages_for_parity(sparity, logical, l, physical, dev,
2643 flags, gen, mirror_num,
2644 have_csum ? csum : NULL);
2645 if (ret)
2646 return ret;
2647 skip:
2648 len -= l;
2649 logical += l;
2650 physical += l;
2651 }
2652 return 0;
2653 }
2654
2655 /*
2656 * Given a physical address, this will calculate it's
2657 * logical offset. if this is a parity stripe, it will return
2658 * the most left data stripe's logical offset.
2659 *
2660 * return 0 if it is a data stripe, 1 means parity stripe.
2661 */
2662 static int get_raid56_logic_offset(u64 physical, int num,
2663 struct map_lookup *map, u64 *offset,
2664 u64 *stripe_start)
2665 {
2666 int i;
2667 int j = 0;
2668 u64 stripe_nr;
2669 u64 last_offset;
2670 u32 stripe_index;
2671 u32 rot;
2672 const int data_stripes = nr_data_stripes(map);
2673
2674 last_offset = (physical - map->stripes[num].physical) * data_stripes;
2675 if (stripe_start)
2676 *stripe_start = last_offset;
2677
2678 *offset = last_offset;
2679 for (i = 0; i < data_stripes; i++) {
2680 *offset = last_offset + i * map->stripe_len;
2681
2682 stripe_nr = div64_u64(*offset, map->stripe_len);
2683 stripe_nr = div_u64(stripe_nr, data_stripes);
2684
2685 /* Work out the disk rotation on this stripe-set */
2686 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);
2687 /* calculate which stripe this data locates */
2688 rot += i;
2689 stripe_index = rot % map->num_stripes;
2690 if (stripe_index == num)
2691 return 0;
2692 if (stripe_index < num)
2693 j++;
2694 }
2695 *offset = last_offset + j * map->stripe_len;
2696 return 1;
2697 }
2698
2699 static void scrub_free_parity(struct scrub_parity *sparity)
2700 {
2701 struct scrub_ctx *sctx = sparity->sctx;
2702 struct scrub_page *curr, *next;
2703 int nbits;
2704
2705 nbits = bitmap_weight(sparity->ebitmap, sparity->nsectors);
2706 if (nbits) {
2707 spin_lock(&sctx->stat_lock);
2708 sctx->stat.read_errors += nbits;
2709 sctx->stat.uncorrectable_errors += nbits;
2710 spin_unlock(&sctx->stat_lock);
2711 }
2712
2713 list_for_each_entry_safe(curr, next, &sparity->spages, list) {
2714 list_del_init(&curr->list);
2715 scrub_page_put(curr);
2716 }
2717
2718 kfree(sparity);
2719 }
2720
2721 static void scrub_parity_bio_endio_worker(struct btrfs_work *work)
2722 {
2723 struct scrub_parity *sparity = container_of(work, struct scrub_parity,
2724 work);
2725 struct scrub_ctx *sctx = sparity->sctx;
2726
2727 scrub_free_parity(sparity);
2728 scrub_pending_bio_dec(sctx);
2729 }
2730
2731 static void scrub_parity_bio_endio(struct bio *bio)
2732 {
2733 struct scrub_parity *sparity = (struct scrub_parity *)bio->bi_private;
2734 struct btrfs_fs_info *fs_info = sparity->sctx->fs_info;
2735
2736 if (bio->bi_status)
2737 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2738 sparity->nsectors);
2739
2740 bio_put(bio);
2741
2742 btrfs_init_work(&sparity->work, scrub_parity_bio_endio_worker, NULL,
2743 NULL);
2744 btrfs_queue_work(fs_info->scrub_parity_workers, &sparity->work);
2745 }
2746
2747 static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
2748 {
2749 struct scrub_ctx *sctx = sparity->sctx;
2750 struct btrfs_fs_info *fs_info = sctx->fs_info;
2751 struct bio *bio;
2752 struct btrfs_raid_bio *rbio;
2753 struct btrfs_bio *bbio = NULL;
2754 u64 length;
2755 int ret;
2756
2757 if (!bitmap_andnot(sparity->dbitmap, sparity->dbitmap, sparity->ebitmap,
2758 sparity->nsectors))
2759 goto out;
2760
2761 length = sparity->logic_end - sparity->logic_start;
2762
2763 btrfs_bio_counter_inc_blocked(fs_info);
2764 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start,
2765 &length, &bbio);
2766 if (ret || !bbio || !bbio->raid_map)
2767 goto bbio_out;
2768
2769 bio = btrfs_io_bio_alloc(0);
2770 bio->bi_iter.bi_sector = sparity->logic_start >> 9;
2771 bio->bi_private = sparity;
2772 bio->bi_end_io = scrub_parity_bio_endio;
2773
2774 rbio = raid56_parity_alloc_scrub_rbio(fs_info, bio, bbio,
2775 length, sparity->scrub_dev,
2776 sparity->dbitmap,
2777 sparity->nsectors);
2778 if (!rbio)
2779 goto rbio_out;
2780
2781 scrub_pending_bio_inc(sctx);
2782 raid56_parity_submit_scrub_rbio(rbio);
2783 return;
2784
2785 rbio_out:
2786 bio_put(bio);
2787 bbio_out:
2788 btrfs_bio_counter_dec(fs_info);
2789 btrfs_put_bbio(bbio);
2790 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2791 sparity->nsectors);
2792 spin_lock(&sctx->stat_lock);
2793 sctx->stat.malloc_errors++;
2794 spin_unlock(&sctx->stat_lock);
2795 out:
2796 scrub_free_parity(sparity);
2797 }
2798
2799 static inline int scrub_calc_parity_bitmap_len(int nsectors)
2800 {
2801 return DIV_ROUND_UP(nsectors, BITS_PER_LONG) * sizeof(long);
2802 }
2803
2804 static void scrub_parity_get(struct scrub_parity *sparity)
2805 {
2806 refcount_inc(&sparity->refs);
2807 }
2808
2809 static void scrub_parity_put(struct scrub_parity *sparity)
2810 {
2811 if (!refcount_dec_and_test(&sparity->refs))
2812 return;
2813
2814 scrub_parity_check_and_repair(sparity);
2815 }
2816
2817 static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
2818 struct map_lookup *map,
2819 struct btrfs_device *sdev,
2820 struct btrfs_path *path,
2821 u64 logic_start,
2822 u64 logic_end)
2823 {
2824 struct btrfs_fs_info *fs_info = sctx->fs_info;
2825 struct btrfs_root *root = fs_info->extent_root;
2826 struct btrfs_root *csum_root = fs_info->csum_root;
2827 struct btrfs_extent_item *extent;
2828 struct btrfs_bio *bbio = NULL;
2829 u64 flags;
2830 int ret;
2831 int slot;
2832 struct extent_buffer *l;
2833 struct btrfs_key key;
2834 u64 generation;
2835 u64 extent_logical;
2836 u64 extent_physical;
2837 u64 extent_len;
2838 u64 mapped_length;
2839 struct btrfs_device *extent_dev;
2840 struct scrub_parity *sparity;
2841 int nsectors;
2842 int bitmap_len;
2843 int extent_mirror_num;
2844 int stop_loop = 0;
2845
2846 nsectors = div_u64(map->stripe_len, fs_info->sectorsize);
2847 bitmap_len = scrub_calc_parity_bitmap_len(nsectors);
2848 sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len,
2849 GFP_NOFS);
2850 if (!sparity) {
2851 spin_lock(&sctx->stat_lock);
2852 sctx->stat.malloc_errors++;
2853 spin_unlock(&sctx->stat_lock);
2854 return -ENOMEM;
2855 }
2856
2857 sparity->stripe_len = map->stripe_len;
2858 sparity->nsectors = nsectors;
2859 sparity->sctx = sctx;
2860 sparity->scrub_dev = sdev;
2861 sparity->logic_start = logic_start;
2862 sparity->logic_end = logic_end;
2863 refcount_set(&sparity->refs, 1);
2864 INIT_LIST_HEAD(&sparity->spages);
2865 sparity->dbitmap = sparity->bitmap;
2866 sparity->ebitmap = (void *)sparity->bitmap + bitmap_len;
2867
2868 ret = 0;
2869 while (logic_start < logic_end) {
2870 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2871 key.type = BTRFS_METADATA_ITEM_KEY;
2872 else
2873 key.type = BTRFS_EXTENT_ITEM_KEY;
2874 key.objectid = logic_start;
2875 key.offset = (u64)-1;
2876
2877 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2878 if (ret < 0)
2879 goto out;
2880
2881 if (ret > 0) {
2882 ret = btrfs_previous_extent_item(root, path, 0);
2883 if (ret < 0)
2884 goto out;
2885 if (ret > 0) {
2886 btrfs_release_path(path);
2887 ret = btrfs_search_slot(NULL, root, &key,
2888 path, 0, 0);
2889 if (ret < 0)
2890 goto out;
2891 }
2892 }
2893
2894 stop_loop = 0;
2895 while (1) {
2896 u64 bytes;
2897
2898 l = path->nodes[0];
2899 slot = path->slots[0];
2900 if (slot >= btrfs_header_nritems(l)) {
2901 ret = btrfs_next_leaf(root, path);
2902 if (ret == 0)
2903 continue;
2904 if (ret < 0)
2905 goto out;
2906
2907 stop_loop = 1;
2908 break;
2909 }
2910 btrfs_item_key_to_cpu(l, &key, slot);
2911
2912 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
2913 key.type != BTRFS_METADATA_ITEM_KEY)
2914 goto next;
2915
2916 if (key.type == BTRFS_METADATA_ITEM_KEY)
2917 bytes = fs_info->nodesize;
2918 else
2919 bytes = key.offset;
2920
2921 if (key.objectid + bytes <= logic_start)
2922 goto next;
2923
2924 if (key.objectid >= logic_end) {
2925 stop_loop = 1;
2926 break;
2927 }
2928
2929 while (key.objectid >= logic_start + map->stripe_len)
2930 logic_start += map->stripe_len;
2931
2932 extent = btrfs_item_ptr(l, slot,
2933 struct btrfs_extent_item);
2934 flags = btrfs_extent_flags(l, extent);
2935 generation = btrfs_extent_generation(l, extent);
2936
2937 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
2938 (key.objectid < logic_start ||
2939 key.objectid + bytes >
2940 logic_start + map->stripe_len)) {
2941 btrfs_err(fs_info,
2942 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
2943 key.objectid, logic_start);
2944 spin_lock(&sctx->stat_lock);
2945 sctx->stat.uncorrectable_errors++;
2946 spin_unlock(&sctx->stat_lock);
2947 goto next;
2948 }
2949 again:
2950 extent_logical = key.objectid;
2951 extent_len = bytes;
2952
2953 if (extent_logical < logic_start) {
2954 extent_len -= logic_start - extent_logical;
2955 extent_logical = logic_start;
2956 }
2957
2958 if (extent_logical + extent_len >
2959 logic_start + map->stripe_len)
2960 extent_len = logic_start + map->stripe_len -
2961 extent_logical;
2962
2963 scrub_parity_mark_sectors_data(sparity, extent_logical,
2964 extent_len);
2965
2966 mapped_length = extent_len;
2967 bbio = NULL;
2968 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ,
2969 extent_logical, &mapped_length, &bbio,
2970 0);
2971 if (!ret) {
2972 if (!bbio || mapped_length < extent_len)
2973 ret = -EIO;
2974 }
2975 if (ret) {
2976 btrfs_put_bbio(bbio);
2977 goto out;
2978 }
2979 extent_physical = bbio->stripes[0].physical;
2980 extent_mirror_num = bbio->mirror_num;
2981 extent_dev = bbio->stripes[0].dev;
2982 btrfs_put_bbio(bbio);
2983
2984 ret = btrfs_lookup_csums_range(csum_root,
2985 extent_logical,
2986 extent_logical + extent_len - 1,
2987 &sctx->csum_list, 1);
2988 if (ret)
2989 goto out;
2990
2991 ret = scrub_extent_for_parity(sparity, extent_logical,
2992 extent_len,
2993 extent_physical,
2994 extent_dev, flags,
2995 generation,
2996 extent_mirror_num);
2997
2998 scrub_free_csums(sctx);
2999
3000 if (ret)
3001 goto out;
3002
3003 if (extent_logical + extent_len <
3004 key.objectid + bytes) {
3005 logic_start += map->stripe_len;
3006
3007 if (logic_start >= logic_end) {
3008 stop_loop = 1;
3009 break;
3010 }
3011
3012 if (logic_start < key.objectid + bytes) {
3013 cond_resched();
3014 goto again;
3015 }
3016 }
3017 next:
3018 path->slots[0]++;
3019 }
3020
3021 btrfs_release_path(path);
3022
3023 if (stop_loop)
3024 break;
3025
3026 logic_start += map->stripe_len;
3027 }
3028 out:
3029 if (ret < 0)
3030 scrub_parity_mark_sectors_error(sparity, logic_start,
3031 logic_end - logic_start);
3032 scrub_parity_put(sparity);
3033 scrub_submit(sctx);
3034 mutex_lock(&sctx->wr_lock);
3035 scrub_wr_submit(sctx);
3036 mutex_unlock(&sctx->wr_lock);
3037
3038 btrfs_release_path(path);
3039 return ret < 0 ? ret : 0;
3040 }
3041
3042 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
3043 struct map_lookup *map,
3044 struct btrfs_device *scrub_dev,
3045 int num, u64 base, u64 length)
3046 {
3047 struct btrfs_path *path, *ppath;
3048 struct btrfs_fs_info *fs_info = sctx->fs_info;
3049 struct btrfs_root *root = fs_info->extent_root;
3050 struct btrfs_root *csum_root = fs_info->csum_root;
3051 struct btrfs_extent_item *extent;
3052 struct blk_plug plug;
3053 u64 flags;
3054 int ret;
3055 int slot;
3056 u64 nstripes;
3057 struct extent_buffer *l;
3058 u64 physical;
3059 u64 logical;
3060 u64 logic_end;
3061 u64 physical_end;
3062 u64 generation;
3063 int mirror_num;
3064 struct reada_control *reada1;
3065 struct reada_control *reada2;
3066 struct btrfs_key key;
3067 struct btrfs_key key_end;
3068 u64 increment = map->stripe_len;
3069 u64 offset;
3070 u64 extent_logical;
3071 u64 extent_physical;
3072 u64 extent_len;
3073 u64 stripe_logical;
3074 u64 stripe_end;
3075 struct btrfs_device *extent_dev;
3076 int extent_mirror_num;
3077 int stop_loop = 0;
3078
3079 physical = map->stripes[num].physical;
3080 offset = 0;
3081 nstripes = div64_u64(length, map->stripe_len);
3082 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3083 offset = map->stripe_len * num;
3084 increment = map->stripe_len * map->num_stripes;
3085 mirror_num = 1;
3086 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3087 int factor = map->num_stripes / map->sub_stripes;
3088 offset = map->stripe_len * (num / map->sub_stripes);
3089 increment = map->stripe_len * factor;
3090 mirror_num = num % map->sub_stripes + 1;
3091 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
3092 increment = map->stripe_len;
3093 mirror_num = num % map->num_stripes + 1;
3094 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
3095 increment = map->stripe_len;
3096 mirror_num = num % map->num_stripes + 1;
3097 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3098 get_raid56_logic_offset(physical, num, map, &offset, NULL);
3099 increment = map->stripe_len * nr_data_stripes(map);
3100 mirror_num = 1;
3101 } else {
3102 increment = map->stripe_len;
3103 mirror_num = 1;
3104 }
3105
3106 path = btrfs_alloc_path();
3107 if (!path)
3108 return -ENOMEM;
3109
3110 ppath = btrfs_alloc_path();
3111 if (!ppath) {
3112 btrfs_free_path(path);
3113 return -ENOMEM;
3114 }
3115
3116 /*
3117 * work on commit root. The related disk blocks are static as
3118 * long as COW is applied. This means, it is save to rewrite
3119 * them to repair disk errors without any race conditions
3120 */
3121 path->search_commit_root = 1;
3122 path->skip_locking = 1;
3123
3124 ppath->search_commit_root = 1;
3125 ppath->skip_locking = 1;
3126 /*
3127 * trigger the readahead for extent tree csum tree and wait for
3128 * completion. During readahead, the scrub is officially paused
3129 * to not hold off transaction commits
3130 */
3131 logical = base + offset;
3132 physical_end = physical + nstripes * map->stripe_len;
3133 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3134 get_raid56_logic_offset(physical_end, num,
3135 map, &logic_end, NULL);
3136 logic_end += base;
3137 } else {
3138 logic_end = logical + increment * nstripes;
3139 }
3140 wait_event(sctx->list_wait,
3141 atomic_read(&sctx->bios_in_flight) == 0);
3142 scrub_blocked_if_needed(fs_info);
3143
3144 /* FIXME it might be better to start readahead at commit root */
3145 key.objectid = logical;
3146 key.type = BTRFS_EXTENT_ITEM_KEY;
3147 key.offset = (u64)0;
3148 key_end.objectid = logic_end;
3149 key_end.type = BTRFS_METADATA_ITEM_KEY;
3150 key_end.offset = (u64)-1;
3151 reada1 = btrfs_reada_add(root, &key, &key_end);
3152
3153 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3154 key.type = BTRFS_EXTENT_CSUM_KEY;
3155 key.offset = logical;
3156 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3157 key_end.type = BTRFS_EXTENT_CSUM_KEY;
3158 key_end.offset = logic_end;
3159 reada2 = btrfs_reada_add(csum_root, &key, &key_end);
3160
3161 if (!IS_ERR(reada1))
3162 btrfs_reada_wait(reada1);
3163 if (!IS_ERR(reada2))
3164 btrfs_reada_wait(reada2);
3165
3166
3167 /*
3168 * collect all data csums for the stripe to avoid seeking during
3169 * the scrub. This might currently (crc32) end up to be about 1MB
3170 */
3171 blk_start_plug(&plug);
3172
3173 /*
3174 * now find all extents for each stripe and scrub them
3175 */
3176 ret = 0;
3177 while (physical < physical_end) {
3178 /*
3179 * canceled?
3180 */
3181 if (atomic_read(&fs_info->scrub_cancel_req) ||
3182 atomic_read(&sctx->cancel_req)) {
3183 ret = -ECANCELED;
3184 goto out;
3185 }
3186 /*
3187 * check to see if we have to pause
3188 */
3189 if (atomic_read(&fs_info->scrub_pause_req)) {
3190 /* push queued extents */
3191 sctx->flush_all_writes = true;
3192 scrub_submit(sctx);
3193 mutex_lock(&sctx->wr_lock);
3194 scrub_wr_submit(sctx);
3195 mutex_unlock(&sctx->wr_lock);
3196 wait_event(sctx->list_wait,
3197 atomic_read(&sctx->bios_in_flight) == 0);
3198 sctx->flush_all_writes = false;
3199 scrub_blocked_if_needed(fs_info);
3200 }
3201
3202 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3203 ret = get_raid56_logic_offset(physical, num, map,
3204 &logical,
3205 &stripe_logical);
3206 logical += base;
3207 if (ret) {
3208 /* it is parity strip */
3209 stripe_logical += base;
3210 stripe_end = stripe_logical + increment;
3211 ret = scrub_raid56_parity(sctx, map, scrub_dev,
3212 ppath, stripe_logical,
3213 stripe_end);
3214 if (ret)
3215 goto out;
3216 goto skip;
3217 }
3218 }
3219
3220 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
3221 key.type = BTRFS_METADATA_ITEM_KEY;
3222 else
3223 key.type = BTRFS_EXTENT_ITEM_KEY;
3224 key.objectid = logical;
3225 key.offset = (u64)-1;
3226
3227 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3228 if (ret < 0)
3229 goto out;
3230
3231 if (ret > 0) {
3232 ret = btrfs_previous_extent_item(root, path, 0);
3233 if (ret < 0)
3234 goto out;
3235 if (ret > 0) {
3236 /* there's no smaller item, so stick with the
3237 * larger one */
3238 btrfs_release_path(path);
3239 ret = btrfs_search_slot(NULL, root, &key,
3240 path, 0, 0);
3241 if (ret < 0)
3242 goto out;
3243 }
3244 }
3245
3246 stop_loop = 0;
3247 while (1) {
3248 u64 bytes;
3249
3250 l = path->nodes[0];
3251 slot = path->slots[0];
3252 if (slot >= btrfs_header_nritems(l)) {
3253 ret = btrfs_next_leaf(root, path);
3254 if (ret == 0)
3255 continue;
3256 if (ret < 0)
3257 goto out;
3258
3259 stop_loop = 1;
3260 break;
3261 }
3262 btrfs_item_key_to_cpu(l, &key, slot);
3263
3264 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
3265 key.type != BTRFS_METADATA_ITEM_KEY)
3266 goto next;
3267
3268 if (key.type == BTRFS_METADATA_ITEM_KEY)
3269 bytes = fs_info->nodesize;
3270 else
3271 bytes = key.offset;
3272
3273 if (key.objectid + bytes <= logical)
3274 goto next;
3275
3276 if (key.objectid >= logical + map->stripe_len) {
3277 /* out of this device extent */
3278 if (key.objectid >= logic_end)
3279 stop_loop = 1;
3280 break;
3281 }
3282
3283 extent = btrfs_item_ptr(l, slot,
3284 struct btrfs_extent_item);
3285 flags = btrfs_extent_flags(l, extent);
3286 generation = btrfs_extent_generation(l, extent);
3287
3288 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
3289 (key.objectid < logical ||
3290 key.objectid + bytes >
3291 logical + map->stripe_len)) {
3292 btrfs_err(fs_info,
3293 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
3294 key.objectid, logical);
3295 spin_lock(&sctx->stat_lock);
3296 sctx->stat.uncorrectable_errors++;
3297 spin_unlock(&sctx->stat_lock);
3298 goto next;
3299 }
3300
3301 again:
3302 extent_logical = key.objectid;
3303 extent_len = bytes;
3304
3305 /*
3306 * trim extent to this stripe
3307 */
3308 if (extent_logical < logical) {
3309 extent_len -= logical - extent_logical;
3310 extent_logical = logical;
3311 }
3312 if (extent_logical + extent_len >
3313 logical + map->stripe_len) {
3314 extent_len = logical + map->stripe_len -
3315 extent_logical;
3316 }
3317
3318 extent_physical = extent_logical - logical + physical;
3319 extent_dev = scrub_dev;
3320 extent_mirror_num = mirror_num;
3321 if (sctx->is_dev_replace)
3322 scrub_remap_extent(fs_info, extent_logical,
3323 extent_len, &extent_physical,
3324 &extent_dev,
3325 &extent_mirror_num);
3326
3327 ret = btrfs_lookup_csums_range(csum_root,
3328 extent_logical,
3329 extent_logical +
3330 extent_len - 1,
3331 &sctx->csum_list, 1);
3332 if (ret)
3333 goto out;
3334
3335 ret = scrub_extent(sctx, map, extent_logical, extent_len,
3336 extent_physical, extent_dev, flags,
3337 generation, extent_mirror_num,
3338 extent_logical - logical + physical);
3339
3340 scrub_free_csums(sctx);
3341
3342 if (ret)
3343 goto out;
3344
3345 if (extent_logical + extent_len <
3346 key.objectid + bytes) {
3347 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3348 /*
3349 * loop until we find next data stripe
3350 * or we have finished all stripes.
3351 */
3352 loop:
3353 physical += map->stripe_len;
3354 ret = get_raid56_logic_offset(physical,
3355 num, map, &logical,
3356 &stripe_logical);
3357 logical += base;
3358
3359 if (ret && physical < physical_end) {
3360 stripe_logical += base;
3361 stripe_end = stripe_logical +
3362 increment;
3363 ret = scrub_raid56_parity(sctx,
3364 map, scrub_dev, ppath,
3365 stripe_logical,
3366 stripe_end);
3367 if (ret)
3368 goto out;
3369 goto loop;
3370 }
3371 } else {
3372 physical += map->stripe_len;
3373 logical += increment;
3374 }
3375 if (logical < key.objectid + bytes) {
3376 cond_resched();
3377 goto again;
3378 }
3379
3380 if (physical >= physical_end) {
3381 stop_loop = 1;
3382 break;
3383 }
3384 }
3385 next:
3386 path->slots[0]++;
3387 }
3388 btrfs_release_path(path);
3389 skip:
3390 logical += increment;
3391 physical += map->stripe_len;
3392 spin_lock(&sctx->stat_lock);
3393 if (stop_loop)
3394 sctx->stat.last_physical = map->stripes[num].physical +
3395 length;
3396 else
3397 sctx->stat.last_physical = physical;
3398 spin_unlock(&sctx->stat_lock);
3399 if (stop_loop)
3400 break;
3401 }
3402 out:
3403 /* push queued extents */
3404 scrub_submit(sctx);
3405 mutex_lock(&sctx->wr_lock);
3406 scrub_wr_submit(sctx);
3407 mutex_unlock(&sctx->wr_lock);
3408
3409 blk_finish_plug(&plug);
3410 btrfs_free_path(path);
3411 btrfs_free_path(ppath);
3412 return ret < 0 ? ret : 0;
3413 }
3414
3415 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
3416 struct btrfs_device *scrub_dev,
3417 u64 chunk_offset, u64 length,
3418 u64 dev_offset,
3419 struct btrfs_block_group *cache)
3420 {
3421 struct btrfs_fs_info *fs_info = sctx->fs_info;
3422 struct extent_map_tree *map_tree = &fs_info->mapping_tree;
3423 struct map_lookup *map;
3424 struct extent_map *em;
3425 int i;
3426 int ret = 0;
3427
3428 read_lock(&map_tree->lock);
3429 em = lookup_extent_mapping(map_tree, chunk_offset, 1);
3430 read_unlock(&map_tree->lock);
3431
3432 if (!em) {
3433 /*
3434 * Might have been an unused block group deleted by the cleaner
3435 * kthread or relocation.
3436 */
3437 spin_lock(&cache->lock);
3438 if (!cache->removed)
3439 ret = -EINVAL;
3440 spin_unlock(&cache->lock);
3441
3442 return ret;
3443 }
3444
3445 map = em->map_lookup;
3446 if (em->start != chunk_offset)
3447 goto out;
3448
3449 if (em->len < length)
3450 goto out;
3451
3452 for (i = 0; i < map->num_stripes; ++i) {
3453 if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
3454 map->stripes[i].physical == dev_offset) {
3455 ret = scrub_stripe(sctx, map, scrub_dev, i,
3456 chunk_offset, length);
3457 if (ret)
3458 goto out;
3459 }
3460 }
3461 out:
3462 free_extent_map(em);
3463
3464 return ret;
3465 }
3466
3467 static noinline_for_stack
3468 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
3469 struct btrfs_device *scrub_dev, u64 start, u64 end)
3470 {
3471 struct btrfs_dev_extent *dev_extent = NULL;
3472 struct btrfs_path *path;
3473 struct btrfs_fs_info *fs_info = sctx->fs_info;
3474 struct btrfs_root *root = fs_info->dev_root;
3475 u64 length;
3476 u64 chunk_offset;
3477 int ret = 0;
3478 int ro_set;
3479 int slot;
3480 struct extent_buffer *l;
3481 struct btrfs_key key;
3482 struct btrfs_key found_key;
3483 struct btrfs_block_group *cache;
3484 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
3485
3486 path = btrfs_alloc_path();
3487 if (!path)
3488 return -ENOMEM;
3489
3490 path->reada = READA_FORWARD;
3491 path->search_commit_root = 1;
3492 path->skip_locking = 1;
3493
3494 key.objectid = scrub_dev->devid;
3495 key.offset = 0ull;
3496 key.type = BTRFS_DEV_EXTENT_KEY;
3497
3498 while (1) {
3499 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3500 if (ret < 0)
3501 break;
3502 if (ret > 0) {
3503 if (path->slots[0] >=
3504 btrfs_header_nritems(path->nodes[0])) {
3505 ret = btrfs_next_leaf(root, path);
3506 if (ret < 0)
3507 break;
3508 if (ret > 0) {
3509 ret = 0;
3510 break;
3511 }
3512 } else {
3513 ret = 0;
3514 }
3515 }
3516
3517 l = path->nodes[0];
3518 slot = path->slots[0];
3519
3520 btrfs_item_key_to_cpu(l, &found_key, slot);
3521
3522 if (found_key.objectid != scrub_dev->devid)
3523 break;
3524
3525 if (found_key.type != BTRFS_DEV_EXTENT_KEY)
3526 break;
3527
3528 if (found_key.offset >= end)
3529 break;
3530
3531 if (found_key.offset < key.offset)
3532 break;
3533
3534 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
3535 length = btrfs_dev_extent_length(l, dev_extent);
3536
3537 if (found_key.offset + length <= start)
3538 goto skip;
3539
3540 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3541
3542 /*
3543 * get a reference on the corresponding block group to prevent
3544 * the chunk from going away while we scrub it
3545 */
3546 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3547
3548 /* some chunks are removed but not committed to disk yet,
3549 * continue scrubbing */
3550 if (!cache)
3551 goto skip;
3552
3553 /*
3554 * we need call btrfs_inc_block_group_ro() with scrubs_paused,
3555 * to avoid deadlock caused by:
3556 * btrfs_inc_block_group_ro()
3557 * -> btrfs_wait_for_commit()
3558 * -> btrfs_commit_transaction()
3559 * -> btrfs_scrub_pause()
3560 */
3561 scrub_pause_on(fs_info);
3562
3563 /*
3564 * Don't do chunk preallocation for scrub.
3565 *
3566 * This is especially important for SYSTEM bgs, or we can hit
3567 * -EFBIG from btrfs_finish_chunk_alloc() like:
3568 * 1. The only SYSTEM bg is marked RO.
3569 * Since SYSTEM bg is small, that's pretty common.
3570 * 2. New SYSTEM bg will be allocated
3571 * Due to regular version will allocate new chunk.
3572 * 3. New SYSTEM bg is empty and will get cleaned up
3573 * Before cleanup really happens, it's marked RO again.
3574 * 4. Empty SYSTEM bg get scrubbed
3575 * We go back to 2.
3576 *
3577 * This can easily boost the amount of SYSTEM chunks if cleaner
3578 * thread can't be triggered fast enough, and use up all space
3579 * of btrfs_super_block::sys_chunk_array
3580 */
3581 ret = btrfs_inc_block_group_ro(cache, false);
3582 if (!ret && sctx->is_dev_replace) {
3583 /*
3584 * If we are doing a device replace wait for any tasks
3585 * that started delalloc right before we set the block
3586 * group to RO mode, as they might have just allocated
3587 * an extent from it or decided they could do a nocow
3588 * write. And if any such tasks did that, wait for their
3589 * ordered extents to complete and then commit the
3590 * current transaction, so that we can later see the new
3591 * extent items in the extent tree - the ordered extents
3592 * create delayed data references (for cow writes) when
3593 * they complete, which will be run and insert the
3594 * corresponding extent items into the extent tree when
3595 * we commit the transaction they used when running
3596 * inode.c:btrfs_finish_ordered_io(). We later use
3597 * the commit root of the extent tree to find extents
3598 * to copy from the srcdev into the tgtdev, and we don't
3599 * want to miss any new extents.
3600 */
3601 btrfs_wait_block_group_reservations(cache);
3602 btrfs_wait_nocow_writers(cache);
3603 ret = btrfs_wait_ordered_roots(fs_info, U64_MAX,
3604 cache->start,
3605 cache->length);
3606 if (ret > 0) {
3607 struct btrfs_trans_handle *trans;
3608
3609 trans = btrfs_join_transaction(root);
3610 if (IS_ERR(trans))
3611 ret = PTR_ERR(trans);
3612 else
3613 ret = btrfs_commit_transaction(trans);
3614 if (ret) {
3615 scrub_pause_off(fs_info);
3616 btrfs_put_block_group(cache);
3617 break;
3618 }
3619 }
3620 }
3621 scrub_pause_off(fs_info);
3622
3623 if (ret == 0) {
3624 ro_set = 1;
3625 } else if (ret == -ENOSPC) {
3626 /*
3627 * btrfs_inc_block_group_ro return -ENOSPC when it
3628 * failed in creating new chunk for metadata.
3629 * It is not a problem for scrub/replace, because
3630 * metadata are always cowed, and our scrub paused
3631 * commit_transactions.
3632 */
3633 ro_set = 0;
3634 } else {
3635 btrfs_warn(fs_info,
3636 "failed setting block group ro: %d", ret);
3637 btrfs_put_block_group(cache);
3638 break;
3639 }
3640
3641 down_write(&dev_replace->rwsem);
3642 dev_replace->cursor_right = found_key.offset + length;
3643 dev_replace->cursor_left = found_key.offset;
3644 dev_replace->item_needs_writeback = 1;
3645 up_write(&dev_replace->rwsem);
3646
3647 ret = scrub_chunk(sctx, scrub_dev, chunk_offset, length,
3648 found_key.offset, cache);
3649
3650 /*
3651 * flush, submit all pending read and write bios, afterwards
3652 * wait for them.
3653 * Note that in the dev replace case, a read request causes
3654 * write requests that are submitted in the read completion
3655 * worker. Therefore in the current situation, it is required
3656 * that all write requests are flushed, so that all read and
3657 * write requests are really completed when bios_in_flight
3658 * changes to 0.
3659 */
3660 sctx->flush_all_writes = true;
3661 scrub_submit(sctx);
3662 mutex_lock(&sctx->wr_lock);
3663 scrub_wr_submit(sctx);
3664 mutex_unlock(&sctx->wr_lock);
3665
3666 wait_event(sctx->list_wait,
3667 atomic_read(&sctx->bios_in_flight) == 0);
3668
3669 scrub_pause_on(fs_info);
3670
3671 /*
3672 * must be called before we decrease @scrub_paused.
3673 * make sure we don't block transaction commit while
3674 * we are waiting pending workers finished.
3675 */
3676 wait_event(sctx->list_wait,
3677 atomic_read(&sctx->workers_pending) == 0);
3678 sctx->flush_all_writes = false;
3679
3680 scrub_pause_off(fs_info);
3681
3682 down_write(&dev_replace->rwsem);
3683 dev_replace->cursor_left = dev_replace->cursor_right;
3684 dev_replace->item_needs_writeback = 1;
3685 up_write(&dev_replace->rwsem);
3686
3687 if (ro_set)
3688 btrfs_dec_block_group_ro(cache);
3689
3690 /*
3691 * We might have prevented the cleaner kthread from deleting
3692 * this block group if it was already unused because we raced
3693 * and set it to RO mode first. So add it back to the unused
3694 * list, otherwise it might not ever be deleted unless a manual
3695 * balance is triggered or it becomes used and unused again.
3696 */
3697 spin_lock(&cache->lock);
3698 if (!cache->removed && !cache->ro && cache->reserved == 0 &&
3699 cache->used == 0) {
3700 spin_unlock(&cache->lock);
3701 btrfs_mark_bg_unused(cache);
3702 } else {
3703 spin_unlock(&cache->lock);
3704 }
3705
3706 btrfs_put_block_group(cache);
3707 if (ret)
3708 break;
3709 if (sctx->is_dev_replace &&
3710 atomic64_read(&dev_replace->num_write_errors) > 0) {
3711 ret = -EIO;
3712 break;
3713 }
3714 if (sctx->stat.malloc_errors > 0) {
3715 ret = -ENOMEM;
3716 break;
3717 }
3718 skip:
3719 key.offset = found_key.offset + length;
3720 btrfs_release_path(path);
3721 }
3722
3723 btrfs_free_path(path);
3724
3725 return ret;
3726 }
3727
3728 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
3729 struct btrfs_device *scrub_dev)
3730 {
3731 int i;
3732 u64 bytenr;
3733 u64 gen;
3734 int ret;
3735 struct btrfs_fs_info *fs_info = sctx->fs_info;
3736
3737 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3738 return -EIO;
3739
3740 /* Seed devices of a new filesystem has their own generation. */
3741 if (scrub_dev->fs_devices != fs_info->fs_devices)
3742 gen = scrub_dev->generation;
3743 else
3744 gen = fs_info->last_trans_committed;
3745
3746 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
3747 bytenr = btrfs_sb_offset(i);
3748 if (bytenr + BTRFS_SUPER_INFO_SIZE >
3749 scrub_dev->commit_total_bytes)
3750 break;
3751
3752 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
3753 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
3754 NULL, 1, bytenr);
3755 if (ret)
3756 return ret;
3757 }
3758 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3759
3760 return 0;
3761 }
3762
3763 /*
3764 * get a reference count on fs_info->scrub_workers. start worker if necessary
3765 */
3766 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
3767 int is_dev_replace)
3768 {
3769 unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND;
3770 int max_active = fs_info->thread_pool_size;
3771
3772 lockdep_assert_held(&fs_info->scrub_lock);
3773
3774 if (refcount_read(&fs_info->scrub_workers_refcnt) == 0) {
3775 ASSERT(fs_info->scrub_workers == NULL);
3776 fs_info->scrub_workers = btrfs_alloc_workqueue(fs_info, "scrub",
3777 flags, is_dev_replace ? 1 : max_active, 4);
3778 if (!fs_info->scrub_workers)
3779 goto fail_scrub_workers;
3780
3781 ASSERT(fs_info->scrub_wr_completion_workers == NULL);
3782 fs_info->scrub_wr_completion_workers =
3783 btrfs_alloc_workqueue(fs_info, "scrubwrc", flags,
3784 max_active, 2);
3785 if (!fs_info->scrub_wr_completion_workers)
3786 goto fail_scrub_wr_completion_workers;
3787
3788 ASSERT(fs_info->scrub_parity_workers == NULL);
3789 fs_info->scrub_parity_workers =
3790 btrfs_alloc_workqueue(fs_info, "scrubparity", flags,
3791 max_active, 2);
3792 if (!fs_info->scrub_parity_workers)
3793 goto fail_scrub_parity_workers;
3794
3795 refcount_set(&fs_info->scrub_workers_refcnt, 1);
3796 } else {
3797 refcount_inc(&fs_info->scrub_workers_refcnt);
3798 }
3799 return 0;
3800
3801 fail_scrub_parity_workers:
3802 btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers);
3803 fail_scrub_wr_completion_workers:
3804 btrfs_destroy_workqueue(fs_info->scrub_workers);
3805 fail_scrub_workers:
3806 return -ENOMEM;
3807 }
3808
3809 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
3810 u64 end, struct btrfs_scrub_progress *progress,
3811 int readonly, int is_dev_replace)
3812 {
3813 struct scrub_ctx *sctx;
3814 int ret;
3815 struct btrfs_device *dev;
3816 unsigned int nofs_flag;
3817 struct btrfs_workqueue *scrub_workers = NULL;
3818 struct btrfs_workqueue *scrub_wr_comp = NULL;
3819 struct btrfs_workqueue *scrub_parity = NULL;
3820
3821 if (btrfs_fs_closing(fs_info))
3822 return -EAGAIN;
3823
3824 if (fs_info->nodesize > BTRFS_STRIPE_LEN) {
3825 /*
3826 * in this case scrub is unable to calculate the checksum
3827 * the way scrub is implemented. Do not handle this
3828 * situation at all because it won't ever happen.
3829 */
3830 btrfs_err(fs_info,
3831 "scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails",
3832 fs_info->nodesize,
3833 BTRFS_STRIPE_LEN);
3834 return -EINVAL;
3835 }
3836
3837 if (fs_info->sectorsize != PAGE_SIZE) {
3838 /* not supported for data w/o checksums */
3839 btrfs_err_rl(fs_info,
3840 "scrub: size assumption sectorsize != PAGE_SIZE (%d != %lu) fails",
3841 fs_info->sectorsize, PAGE_SIZE);
3842 return -EINVAL;
3843 }
3844
3845 if (fs_info->nodesize >
3846 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK ||
3847 fs_info->sectorsize > PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) {
3848 /*
3849 * would exhaust the array bounds of pagev member in
3850 * struct scrub_block
3851 */
3852 btrfs_err(fs_info,
3853 "scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails",
3854 fs_info->nodesize,
3855 SCRUB_MAX_PAGES_PER_BLOCK,
3856 fs_info->sectorsize,
3857 SCRUB_MAX_PAGES_PER_BLOCK);
3858 return -EINVAL;
3859 }
3860
3861 /* Allocate outside of device_list_mutex */
3862 sctx = scrub_setup_ctx(fs_info, is_dev_replace);
3863 if (IS_ERR(sctx))
3864 return PTR_ERR(sctx);
3865
3866 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3867 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
3868 if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) &&
3869 !is_dev_replace)) {
3870 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3871 ret = -ENODEV;
3872 goto out_free_ctx;
3873 }
3874
3875 if (!is_dev_replace && !readonly &&
3876 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) {
3877 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3878 btrfs_err_in_rcu(fs_info, "scrub: device %s is not writable",
3879 rcu_str_deref(dev->name));
3880 ret = -EROFS;
3881 goto out_free_ctx;
3882 }
3883
3884 mutex_lock(&fs_info->scrub_lock);
3885 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3886 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) {
3887 mutex_unlock(&fs_info->scrub_lock);
3888 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3889 ret = -EIO;
3890 goto out_free_ctx;
3891 }
3892
3893 down_read(&fs_info->dev_replace.rwsem);
3894 if (dev->scrub_ctx ||
3895 (!is_dev_replace &&
3896 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
3897 up_read(&fs_info->dev_replace.rwsem);
3898 mutex_unlock(&fs_info->scrub_lock);
3899 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3900 ret = -EINPROGRESS;
3901 goto out_free_ctx;
3902 }
3903 up_read(&fs_info->dev_replace.rwsem);
3904
3905 ret = scrub_workers_get(fs_info, is_dev_replace);
3906 if (ret) {
3907 mutex_unlock(&fs_info->scrub_lock);
3908 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3909 goto out_free_ctx;
3910 }
3911
3912 sctx->readonly = readonly;
3913 dev->scrub_ctx = sctx;
3914 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3915
3916 /*
3917 * checking @scrub_pause_req here, we can avoid
3918 * race between committing transaction and scrubbing.
3919 */
3920 __scrub_blocked_if_needed(fs_info);
3921 atomic_inc(&fs_info->scrubs_running);
3922 mutex_unlock(&fs_info->scrub_lock);
3923
3924 /*
3925 * In order to avoid deadlock with reclaim when there is a transaction
3926 * trying to pause scrub, make sure we use GFP_NOFS for all the
3927 * allocations done at btrfs_scrub_pages() and scrub_pages_for_parity()
3928 * invoked by our callees. The pausing request is done when the
3929 * transaction commit starts, and it blocks the transaction until scrub
3930 * is paused (done at specific points at scrub_stripe() or right above
3931 * before incrementing fs_info->scrubs_running).
3932 */
3933 nofs_flag = memalloc_nofs_save();
3934 if (!is_dev_replace) {
3935 btrfs_info(fs_info, "scrub: started on devid %llu", devid);
3936 /*
3937 * by holding device list mutex, we can
3938 * kick off writing super in log tree sync.
3939 */
3940 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3941 ret = scrub_supers(sctx, dev);
3942 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3943 }
3944
3945 if (!ret)
3946 ret = scrub_enumerate_chunks(sctx, dev, start, end);
3947 memalloc_nofs_restore(nofs_flag);
3948
3949 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3950 atomic_dec(&fs_info->scrubs_running);
3951 wake_up(&fs_info->scrub_pause_wait);
3952
3953 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0);
3954
3955 if (progress)
3956 memcpy(progress, &sctx->stat, sizeof(*progress));
3957
3958 if (!is_dev_replace)
3959 btrfs_info(fs_info, "scrub: %s on devid %llu with status: %d",
3960 ret ? "not finished" : "finished", devid, ret);
3961
3962 mutex_lock(&fs_info->scrub_lock);
3963 dev->scrub_ctx = NULL;
3964 if (refcount_dec_and_test(&fs_info->scrub_workers_refcnt)) {
3965 scrub_workers = fs_info->scrub_workers;
3966 scrub_wr_comp = fs_info->scrub_wr_completion_workers;
3967 scrub_parity = fs_info->scrub_parity_workers;
3968
3969 fs_info->scrub_workers = NULL;
3970 fs_info->scrub_wr_completion_workers = NULL;
3971 fs_info->scrub_parity_workers = NULL;
3972 }
3973 mutex_unlock(&fs_info->scrub_lock);
3974
3975 btrfs_destroy_workqueue(scrub_workers);
3976 btrfs_destroy_workqueue(scrub_wr_comp);
3977 btrfs_destroy_workqueue(scrub_parity);
3978 scrub_put_ctx(sctx);
3979
3980 return ret;
3981
3982 out_free_ctx:
3983 scrub_free_ctx(sctx);
3984
3985 return ret;
3986 }
3987
3988 void btrfs_scrub_pause(struct btrfs_fs_info *fs_info)
3989 {
3990 mutex_lock(&fs_info->scrub_lock);
3991 atomic_inc(&fs_info->scrub_pause_req);
3992 while (atomic_read(&fs_info->scrubs_paused) !=
3993 atomic_read(&fs_info->scrubs_running)) {
3994 mutex_unlock(&fs_info->scrub_lock);
3995 wait_event(fs_info->scrub_pause_wait,
3996 atomic_read(&fs_info->scrubs_paused) ==
3997 atomic_read(&fs_info->scrubs_running));
3998 mutex_lock(&fs_info->scrub_lock);
3999 }
4000 mutex_unlock(&fs_info->scrub_lock);
4001 }
4002
4003 void btrfs_scrub_continue(struct btrfs_fs_info *fs_info)
4004 {
4005 atomic_dec(&fs_info->scrub_pause_req);
4006 wake_up(&fs_info->scrub_pause_wait);
4007 }
4008
4009 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
4010 {
4011 mutex_lock(&fs_info->scrub_lock);
4012 if (!atomic_read(&fs_info->scrubs_running)) {
4013 mutex_unlock(&fs_info->scrub_lock);
4014 return -ENOTCONN;
4015 }
4016
4017 atomic_inc(&fs_info->scrub_cancel_req);
4018 while (atomic_read(&fs_info->scrubs_running)) {
4019 mutex_unlock(&fs_info->scrub_lock);
4020 wait_event(fs_info->scrub_pause_wait,
4021 atomic_read(&fs_info->scrubs_running) == 0);
4022 mutex_lock(&fs_info->scrub_lock);
4023 }
4024 atomic_dec(&fs_info->scrub_cancel_req);
4025 mutex_unlock(&fs_info->scrub_lock);
4026
4027 return 0;
4028 }
4029
4030 int btrfs_scrub_cancel_dev(struct btrfs_device *dev)
4031 {
4032 struct btrfs_fs_info *fs_info = dev->fs_info;
4033 struct scrub_ctx *sctx;
4034
4035 mutex_lock(&fs_info->scrub_lock);
4036 sctx = dev->scrub_ctx;
4037 if (!sctx) {
4038 mutex_unlock(&fs_info->scrub_lock);
4039 return -ENOTCONN;
4040 }
4041 atomic_inc(&sctx->cancel_req);
4042 while (dev->scrub_ctx) {
4043 mutex_unlock(&fs_info->scrub_lock);
4044 wait_event(fs_info->scrub_pause_wait,
4045 dev->scrub_ctx == NULL);
4046 mutex_lock(&fs_info->scrub_lock);
4047 }
4048 mutex_unlock(&fs_info->scrub_lock);
4049
4050 return 0;
4051 }
4052
4053 int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid,
4054 struct btrfs_scrub_progress *progress)
4055 {
4056 struct btrfs_device *dev;
4057 struct scrub_ctx *sctx = NULL;
4058
4059 mutex_lock(&fs_info->fs_devices->device_list_mutex);
4060 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
4061 if (dev)
4062 sctx = dev->scrub_ctx;
4063 if (sctx)
4064 memcpy(progress, &sctx->stat, sizeof(*progress));
4065 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
4066
4067 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
4068 }
4069
4070 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
4071 u64 extent_logical, u64 extent_len,
4072 u64 *extent_physical,
4073 struct btrfs_device **extent_dev,
4074 int *extent_mirror_num)
4075 {
4076 u64 mapped_length;
4077 struct btrfs_bio *bbio = NULL;
4078 int ret;
4079
4080 mapped_length = extent_len;
4081 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, extent_logical,
4082 &mapped_length, &bbio, 0);
4083 if (ret || !bbio || mapped_length < extent_len ||
4084 !bbio->stripes[0].dev->bdev) {
4085 btrfs_put_bbio(bbio);
4086 return;
4087 }
4088
4089 *extent_physical = bbio->stripes[0].physical;
4090 *extent_mirror_num = bbio->mirror_num;
4091 *extent_dev = bbio->stripes[0].dev;
4092 btrfs_put_bbio(bbio);
4093 }
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