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Linux 4.19-rc7
[linux-2.6/btrfs-unstable.git] / fs / btrfs / scrub.c
blob3be1456b5116b3e80dca1f466f374c4eb46a28cd
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2011, 2012 STRATO. All rights reserved.
4 */
5
6 #include <linux/blkdev.h>
7 #include <linux/ratelimit.h>
8 #include <linux/sched/mm.h>
9 #include "ctree.h"
10 #include "volumes.h"
11 #include "disk-io.h"
12 #include "ordered-data.h"
13 #include "transaction.h"
14 #include "backref.h"
15 #include "extent_io.h"
16 #include "dev-replace.h"
17 #include "check-integrity.h"
18 #include "rcu-string.h"
19 #include "raid56.h"
20
21 /*
22 * This is only the first step towards a full-features scrub. It reads all
23 * extent and super block and verifies the checksums. In case a bad checksum
24 * is found or the extent cannot be read, good data will be written back if
25 * any can be found.
26 *
27 * Future enhancements:
28 * - In case an unrepairable extent is encountered, track which files are
29 * affected and report them
30 * - track and record media errors, throw out bad devices
31 * - add a mode to also read unallocated space
32 */
33
34 struct scrub_block;
35 struct scrub_ctx;
36
37 /*
38 * the following three values only influence the performance.
39 * The last one configures the number of parallel and outstanding I/O
40 * operations. The first two values configure an upper limit for the number
41 * of (dynamically allocated) pages that are added to a bio.
42 */
43 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */
44 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */
45 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */
46
47 /*
48 * the following value times PAGE_SIZE needs to be large enough to match the
49 * largest node/leaf/sector size that shall be supported.
50 * Values larger than BTRFS_STRIPE_LEN are not supported.
51 */
52 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
53
54 struct scrub_recover {
55 refcount_t refs;
56 struct btrfs_bio *bbio;
57 u64 map_length;
58 };
59
60 struct scrub_page {
61 struct scrub_block *sblock;
62 struct page *page;
63 struct btrfs_device *dev;
64 struct list_head list;
65 u64 flags; /* extent flags */
66 u64 generation;
67 u64 logical;
68 u64 physical;
69 u64 physical_for_dev_replace;
70 atomic_t refs;
71 struct {
72 unsigned int mirror_num:8;
73 unsigned int have_csum:1;
74 unsigned int io_error:1;
75 };
76 u8 csum[BTRFS_CSUM_SIZE];
77
78 struct scrub_recover *recover;
79 };
80
81 struct scrub_bio {
82 int index;
83 struct scrub_ctx *sctx;
84 struct btrfs_device *dev;
85 struct bio *bio;
86 blk_status_t status;
87 u64 logical;
88 u64 physical;
89 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO
90 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO];
91 #else
92 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO];
93 #endif
94 int page_count;
95 int next_free;
96 struct btrfs_work work;
97 };
98
99 struct scrub_block {
100 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK];
101 int page_count;
102 atomic_t outstanding_pages;
103 refcount_t refs; /* free mem on transition to zero */
104 struct scrub_ctx *sctx;
105 struct scrub_parity *sparity;
106 struct {
107 unsigned int header_error:1;
108 unsigned int checksum_error:1;
109 unsigned int no_io_error_seen:1;
110 unsigned int generation_error:1; /* also sets header_error */
111
112 /* The following is for the data used to check parity */
113 /* It is for the data with checksum */
114 unsigned int data_corrected:1;
115 };
116 struct btrfs_work work;
117 };
118
119 /* Used for the chunks with parity stripe such RAID5/6 */
120 struct scrub_parity {
121 struct scrub_ctx *sctx;
122
123 struct btrfs_device *scrub_dev;
124
125 u64 logic_start;
126
127 u64 logic_end;
128
129 int nsectors;
130
131 u64 stripe_len;
132
133 refcount_t refs;
134
135 struct list_head spages;
136
137 /* Work of parity check and repair */
138 struct btrfs_work work;
139
140 /* Mark the parity blocks which have data */
141 unsigned long *dbitmap;
142
143 /*
144 * Mark the parity blocks which have data, but errors happen when
145 * read data or check data
146 */
147 unsigned long *ebitmap;
148
149 unsigned long bitmap[0];
150 };
151
152 struct scrub_ctx {
153 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX];
154 struct btrfs_fs_info *fs_info;
155 int first_free;
156 int curr;
157 atomic_t bios_in_flight;
158 atomic_t workers_pending;
159 spinlock_t list_lock;
160 wait_queue_head_t list_wait;
161 u16 csum_size;
162 struct list_head csum_list;
163 atomic_t cancel_req;
164 int readonly;
165 int pages_per_rd_bio;
166
167 int is_dev_replace;
168
169 struct scrub_bio *wr_curr_bio;
170 struct mutex wr_lock;
171 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
172 struct btrfs_device *wr_tgtdev;
173 bool flush_all_writes;
174
175 /*
176 * statistics
177 */
178 struct btrfs_scrub_progress stat;
179 spinlock_t stat_lock;
180
181 /*
182 * Use a ref counter to avoid use-after-free issues. Scrub workers
183 * decrement bios_in_flight and workers_pending and then do a wakeup
184 * on the list_wait wait queue. We must ensure the main scrub task
185 * doesn't free the scrub context before or while the workers are
186 * doing the wakeup() call.
187 */
188 refcount_t refs;
189 };
190
191 struct scrub_warning {
192 struct btrfs_path *path;
193 u64 extent_item_size;
194 const char *errstr;
195 u64 physical;
196 u64 logical;
197 struct btrfs_device *dev;
198 };
199
200 struct full_stripe_lock {
201 struct rb_node node;
202 u64 logical;
203 u64 refs;
204 struct mutex mutex;
205 };
206
207 static void scrub_pending_bio_inc(struct scrub_ctx *sctx);
208 static void scrub_pending_bio_dec(struct scrub_ctx *sctx);
209 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
210 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
211 struct scrub_block *sblocks_for_recheck);
212 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
213 struct scrub_block *sblock,
214 int retry_failed_mirror);
215 static void scrub_recheck_block_checksum(struct scrub_block *sblock);
216 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
217 struct scrub_block *sblock_good);
218 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
219 struct scrub_block *sblock_good,
220 int page_num, int force_write);
221 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock);
222 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
223 int page_num);
224 static int scrub_checksum_data(struct scrub_block *sblock);
225 static int scrub_checksum_tree_block(struct scrub_block *sblock);
226 static int scrub_checksum_super(struct scrub_block *sblock);
227 static void scrub_block_get(struct scrub_block *sblock);
228 static void scrub_block_put(struct scrub_block *sblock);
229 static void scrub_page_get(struct scrub_page *spage);
230 static void scrub_page_put(struct scrub_page *spage);
231 static void scrub_parity_get(struct scrub_parity *sparity);
232 static void scrub_parity_put(struct scrub_parity *sparity);
233 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
234 struct scrub_page *spage);
235 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
236 u64 physical, struct btrfs_device *dev, u64 flags,
237 u64 gen, int mirror_num, u8 *csum, int force,
238 u64 physical_for_dev_replace);
239 static void scrub_bio_end_io(struct bio *bio);
240 static void scrub_bio_end_io_worker(struct btrfs_work *work);
241 static void scrub_block_complete(struct scrub_block *sblock);
242 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
243 u64 extent_logical, u64 extent_len,
244 u64 *extent_physical,
245 struct btrfs_device **extent_dev,
246 int *extent_mirror_num);
247 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
248 struct scrub_page *spage);
249 static void scrub_wr_submit(struct scrub_ctx *sctx);
250 static void scrub_wr_bio_end_io(struct bio *bio);
251 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work);
252 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
253 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info);
254 static void scrub_put_ctx(struct scrub_ctx *sctx);
255
256 static inline int scrub_is_page_on_raid56(struct scrub_page *page)
257 {
258 return page->recover &&
259 (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK);
260 }
261
262 static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
263 {
264 refcount_inc(&sctx->refs);
265 atomic_inc(&sctx->bios_in_flight);
266 }
267
268 static void scrub_pending_bio_dec(struct scrub_ctx *sctx)
269 {
270 atomic_dec(&sctx->bios_in_flight);
271 wake_up(&sctx->list_wait);
272 scrub_put_ctx(sctx);
273 }
274
275 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
276 {
277 while (atomic_read(&fs_info->scrub_pause_req)) {
278 mutex_unlock(&fs_info->scrub_lock);
279 wait_event(fs_info->scrub_pause_wait,
280 atomic_read(&fs_info->scrub_pause_req) == 0);
281 mutex_lock(&fs_info->scrub_lock);
282 }
283 }
284
285 static void scrub_pause_on(struct btrfs_fs_info *fs_info)
286 {
287 atomic_inc(&fs_info->scrubs_paused);
288 wake_up(&fs_info->scrub_pause_wait);
289 }
290
291 static void scrub_pause_off(struct btrfs_fs_info *fs_info)
292 {
293 mutex_lock(&fs_info->scrub_lock);
294 __scrub_blocked_if_needed(fs_info);
295 atomic_dec(&fs_info->scrubs_paused);
296 mutex_unlock(&fs_info->scrub_lock);
297
298 wake_up(&fs_info->scrub_pause_wait);
299 }
300
301 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info)
302 {
303 scrub_pause_on(fs_info);
304 scrub_pause_off(fs_info);
305 }
306
307 /*
308 * Insert new full stripe lock into full stripe locks tree
309 *
310 * Return pointer to existing or newly inserted full_stripe_lock structure if
311 * everything works well.
312 * Return ERR_PTR(-ENOMEM) if we failed to allocate memory
313 *
314 * NOTE: caller must hold full_stripe_locks_root->lock before calling this
315 * function
316 */
317 static struct full_stripe_lock *insert_full_stripe_lock(
318 struct btrfs_full_stripe_locks_tree *locks_root,
319 u64 fstripe_logical)
320 {
321 struct rb_node **p;
322 struct rb_node *parent = NULL;
323 struct full_stripe_lock *entry;
324 struct full_stripe_lock *ret;
325
326 lockdep_assert_held(&locks_root->lock);
327
328 p = &locks_root->root.rb_node;
329 while (*p) {
330 parent = *p;
331 entry = rb_entry(parent, struct full_stripe_lock, node);
332 if (fstripe_logical < entry->logical) {
333 p = &(*p)->rb_left;
334 } else if (fstripe_logical > entry->logical) {
335 p = &(*p)->rb_right;
336 } else {
337 entry->refs++;
338 return entry;
339 }
340 }
341
342 /* Insert new lock */
343 ret = kmalloc(sizeof(*ret), GFP_KERNEL);
344 if (!ret)
345 return ERR_PTR(-ENOMEM);
346 ret->logical = fstripe_logical;
347 ret->refs = 1;
348 mutex_init(&ret->mutex);
349
350 rb_link_node(&ret->node, parent, p);
351 rb_insert_color(&ret->node, &locks_root->root);
352 return ret;
353 }
354
355 /*
356 * Search for a full stripe lock of a block group
357 *
358 * Return pointer to existing full stripe lock if found
359 * Return NULL if not found
360 */
361 static struct full_stripe_lock *search_full_stripe_lock(
362 struct btrfs_full_stripe_locks_tree *locks_root,
363 u64 fstripe_logical)
364 {
365 struct rb_node *node;
366 struct full_stripe_lock *entry;
367
368 lockdep_assert_held(&locks_root->lock);
369
370 node = locks_root->root.rb_node;
371 while (node) {
372 entry = rb_entry(node, struct full_stripe_lock, node);
373 if (fstripe_logical < entry->logical)
374 node = node->rb_left;
375 else if (fstripe_logical > entry->logical)
376 node = node->rb_right;
377 else
378 return entry;
379 }
380 return NULL;
381 }
382
383 /*
384 * Helper to get full stripe logical from a normal bytenr.
385 *
386 * Caller must ensure @cache is a RAID56 block group.
387 */
388 static u64 get_full_stripe_logical(struct btrfs_block_group_cache *cache,
389 u64 bytenr)
390 {
391 u64 ret;
392
393 /*
394 * Due to chunk item size limit, full stripe length should not be
395 * larger than U32_MAX. Just a sanity check here.
396 */
397 WARN_ON_ONCE(cache->full_stripe_len >= U32_MAX);
398
399 /*
400 * round_down() can only handle power of 2, while RAID56 full
401 * stripe length can be 64KiB * n, so we need to manually round down.
402 */
403 ret = div64_u64(bytenr - cache->key.objectid, cache->full_stripe_len) *
404 cache->full_stripe_len + cache->key.objectid;
405 return ret;
406 }
407
408 /*
409 * Lock a full stripe to avoid concurrency of recovery and read
410 *
411 * It's only used for profiles with parities (RAID5/6), for other profiles it
412 * does nothing.
413 *
414 * Return 0 if we locked full stripe covering @bytenr, with a mutex held.
415 * So caller must call unlock_full_stripe() at the same context.
416 *
417 * Return <0 if encounters error.
418 */
419 static int lock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
420 bool *locked_ret)
421 {
422 struct btrfs_block_group_cache *bg_cache;
423 struct btrfs_full_stripe_locks_tree *locks_root;
424 struct full_stripe_lock *existing;
425 u64 fstripe_start;
426 int ret = 0;
427
428 *locked_ret = false;
429 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
430 if (!bg_cache) {
431 ASSERT(0);
432 return -ENOENT;
433 }
434
435 /* Profiles not based on parity don't need full stripe lock */
436 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
437 goto out;
438 locks_root = &bg_cache->full_stripe_locks_root;
439
440 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
441
442 /* Now insert the full stripe lock */
443 mutex_lock(&locks_root->lock);
444 existing = insert_full_stripe_lock(locks_root, fstripe_start);
445 mutex_unlock(&locks_root->lock);
446 if (IS_ERR(existing)) {
447 ret = PTR_ERR(existing);
448 goto out;
449 }
450 mutex_lock(&existing->mutex);
451 *locked_ret = true;
452 out:
453 btrfs_put_block_group(bg_cache);
454 return ret;
455 }
456
457 /*
458 * Unlock a full stripe.
459 *
460 * NOTE: Caller must ensure it's the same context calling corresponding
461 * lock_full_stripe().
462 *
463 * Return 0 if we unlock full stripe without problem.
464 * Return <0 for error
465 */
466 static int unlock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr,
467 bool locked)
468 {
469 struct btrfs_block_group_cache *bg_cache;
470 struct btrfs_full_stripe_locks_tree *locks_root;
471 struct full_stripe_lock *fstripe_lock;
472 u64 fstripe_start;
473 bool freeit = false;
474 int ret = 0;
475
476 /* If we didn't acquire full stripe lock, no need to continue */
477 if (!locked)
478 return 0;
479
480 bg_cache = btrfs_lookup_block_group(fs_info, bytenr);
481 if (!bg_cache) {
482 ASSERT(0);
483 return -ENOENT;
484 }
485 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK))
486 goto out;
487
488 locks_root = &bg_cache->full_stripe_locks_root;
489 fstripe_start = get_full_stripe_logical(bg_cache, bytenr);
490
491 mutex_lock(&locks_root->lock);
492 fstripe_lock = search_full_stripe_lock(locks_root, fstripe_start);
493 /* Unpaired unlock_full_stripe() detected */
494 if (!fstripe_lock) {
495 WARN_ON(1);
496 ret = -ENOENT;
497 mutex_unlock(&locks_root->lock);
498 goto out;
499 }
500
501 if (fstripe_lock->refs == 0) {
502 WARN_ON(1);
503 btrfs_warn(fs_info, "full stripe lock at %llu refcount underflow",
504 fstripe_lock->logical);
505 } else {
506 fstripe_lock->refs--;
507 }
508
509 if (fstripe_lock->refs == 0) {
510 rb_erase(&fstripe_lock->node, &locks_root->root);
511 freeit = true;
512 }
513 mutex_unlock(&locks_root->lock);
514
515 mutex_unlock(&fstripe_lock->mutex);
516 if (freeit)
517 kfree(fstripe_lock);
518 out:
519 btrfs_put_block_group(bg_cache);
520 return ret;
521 }
522
523 static void scrub_free_csums(struct scrub_ctx *sctx)
524 {
525 while (!list_empty(&sctx->csum_list)) {
526 struct btrfs_ordered_sum *sum;
527 sum = list_first_entry(&sctx->csum_list,
528 struct btrfs_ordered_sum, list);
529 list_del(&sum->list);
530 kfree(sum);
531 }
532 }
533
534 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
535 {
536 int i;
537
538 if (!sctx)
539 return;
540
541 /* this can happen when scrub is cancelled */
542 if (sctx->curr != -1) {
543 struct scrub_bio *sbio = sctx->bios[sctx->curr];
544
545 for (i = 0; i < sbio->page_count; i++) {
546 WARN_ON(!sbio->pagev[i]->page);
547 scrub_block_put(sbio->pagev[i]->sblock);
548 }
549 bio_put(sbio->bio);
550 }
551
552 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
553 struct scrub_bio *sbio = sctx->bios[i];
554
555 if (!sbio)
556 break;
557 kfree(sbio);
558 }
559
560 kfree(sctx->wr_curr_bio);
561 scrub_free_csums(sctx);
562 kfree(sctx);
563 }
564
565 static void scrub_put_ctx(struct scrub_ctx *sctx)
566 {
567 if (refcount_dec_and_test(&sctx->refs))
568 scrub_free_ctx(sctx);
569 }
570
571 static noinline_for_stack
572 struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
573 {
574 struct scrub_ctx *sctx;
575 int i;
576 struct btrfs_fs_info *fs_info = dev->fs_info;
577
578 sctx = kzalloc(sizeof(*sctx), GFP_KERNEL);
579 if (!sctx)
580 goto nomem;
581 refcount_set(&sctx->refs, 1);
582 sctx->is_dev_replace = is_dev_replace;
583 sctx->pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
584 sctx->curr = -1;
585 sctx->fs_info = dev->fs_info;
586 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
587 struct scrub_bio *sbio;
588
589 sbio = kzalloc(sizeof(*sbio), GFP_KERNEL);
590 if (!sbio)
591 goto nomem;
592 sctx->bios[i] = sbio;
593
594 sbio->index = i;
595 sbio->sctx = sctx;
596 sbio->page_count = 0;
597 btrfs_init_work(&sbio->work, btrfs_scrub_helper,
598 scrub_bio_end_io_worker, NULL, NULL);
599
600 if (i != SCRUB_BIOS_PER_SCTX - 1)
601 sctx->bios[i]->next_free = i + 1;
602 else
603 sctx->bios[i]->next_free = -1;
604 }
605 sctx->first_free = 0;
606 atomic_set(&sctx->bios_in_flight, 0);
607 atomic_set(&sctx->workers_pending, 0);
608 atomic_set(&sctx->cancel_req, 0);
609 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
610 INIT_LIST_HEAD(&sctx->csum_list);
611
612 spin_lock_init(&sctx->list_lock);
613 spin_lock_init(&sctx->stat_lock);
614 init_waitqueue_head(&sctx->list_wait);
615
616 WARN_ON(sctx->wr_curr_bio != NULL);
617 mutex_init(&sctx->wr_lock);
618 sctx->wr_curr_bio = NULL;
619 if (is_dev_replace) {
620 WARN_ON(!fs_info->dev_replace.tgtdev);
621 sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO;
622 sctx->wr_tgtdev = fs_info->dev_replace.tgtdev;
623 sctx->flush_all_writes = false;
624 }
625
626 return sctx;
627
628 nomem:
629 scrub_free_ctx(sctx);
630 return ERR_PTR(-ENOMEM);
631 }
632
633 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root,
634 void *warn_ctx)
635 {
636 u64 isize;
637 u32 nlink;
638 int ret;
639 int i;
640 unsigned nofs_flag;
641 struct extent_buffer *eb;
642 struct btrfs_inode_item *inode_item;
643 struct scrub_warning *swarn = warn_ctx;
644 struct btrfs_fs_info *fs_info = swarn->dev->fs_info;
645 struct inode_fs_paths *ipath = NULL;
646 struct btrfs_root *local_root;
647 struct btrfs_key root_key;
648 struct btrfs_key key;
649
650 root_key.objectid = root;
651 root_key.type = BTRFS_ROOT_ITEM_KEY;
652 root_key.offset = (u64)-1;
653 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
654 if (IS_ERR(local_root)) {
655 ret = PTR_ERR(local_root);
656 goto err;
657 }
658
659 /*
660 * this makes the path point to (inum INODE_ITEM ioff)
661 */
662 key.objectid = inum;
663 key.type = BTRFS_INODE_ITEM_KEY;
664 key.offset = 0;
665
666 ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0);
667 if (ret) {
668 btrfs_release_path(swarn->path);
669 goto err;
670 }
671
672 eb = swarn->path->nodes[0];
673 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
674 struct btrfs_inode_item);
675 isize = btrfs_inode_size(eb, inode_item);
676 nlink = btrfs_inode_nlink(eb, inode_item);
677 btrfs_release_path(swarn->path);
678
679 /*
680 * init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub
681 * uses GFP_NOFS in this context, so we keep it consistent but it does
682 * not seem to be strictly necessary.
683 */
684 nofs_flag = memalloc_nofs_save();
685 ipath = init_ipath(4096, local_root, swarn->path);
686 memalloc_nofs_restore(nofs_flag);
687 if (IS_ERR(ipath)) {
688 ret = PTR_ERR(ipath);
689 ipath = NULL;
690 goto err;
691 }
692 ret = paths_from_inode(inum, ipath);
693
694 if (ret < 0)
695 goto err;
696
697 /*
698 * we deliberately ignore the bit ipath might have been too small to
699 * hold all of the paths here
700 */
701 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
702 btrfs_warn_in_rcu(fs_info,
703 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %llu, links %u (path: %s)",
704 swarn->errstr, swarn->logical,
705 rcu_str_deref(swarn->dev->name),
706 swarn->physical,
707 root, inum, offset,
708 min(isize - offset, (u64)PAGE_SIZE), nlink,
709 (char *)(unsigned long)ipath->fspath->val[i]);
710
711 free_ipath(ipath);
712 return 0;
713
714 err:
715 btrfs_warn_in_rcu(fs_info,
716 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d",
717 swarn->errstr, swarn->logical,
718 rcu_str_deref(swarn->dev->name),
719 swarn->physical,
720 root, inum, offset, ret);
721
722 free_ipath(ipath);
723 return 0;
724 }
725
726 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
727 {
728 struct btrfs_device *dev;
729 struct btrfs_fs_info *fs_info;
730 struct btrfs_path *path;
731 struct btrfs_key found_key;
732 struct extent_buffer *eb;
733 struct btrfs_extent_item *ei;
734 struct scrub_warning swarn;
735 unsigned long ptr = 0;
736 u64 extent_item_pos;
737 u64 flags = 0;
738 u64 ref_root;
739 u32 item_size;
740 u8 ref_level = 0;
741 int ret;
742
743 WARN_ON(sblock->page_count < 1);
744 dev = sblock->pagev[0]->dev;
745 fs_info = sblock->sctx->fs_info;
746
747 path = btrfs_alloc_path();
748 if (!path)
749 return;
750
751 swarn.physical = sblock->pagev[0]->physical;
752 swarn.logical = sblock->pagev[0]->logical;
753 swarn.errstr = errstr;
754 swarn.dev = NULL;
755
756 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
757 &flags);
758 if (ret < 0)
759 goto out;
760
761 extent_item_pos = swarn.logical - found_key.objectid;
762 swarn.extent_item_size = found_key.offset;
763
764 eb = path->nodes[0];
765 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
766 item_size = btrfs_item_size_nr(eb, path->slots[0]);
767
768 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
769 do {
770 ret = tree_backref_for_extent(&ptr, eb, &found_key, ei,
771 item_size, &ref_root,
772 &ref_level);
773 btrfs_warn_in_rcu(fs_info,
774 "%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu",
775 errstr, swarn.logical,
776 rcu_str_deref(dev->name),
777 swarn.physical,
778 ref_level ? "node" : "leaf",
779 ret < 0 ? -1 : ref_level,
780 ret < 0 ? -1 : ref_root);
781 } while (ret != 1);
782 btrfs_release_path(path);
783 } else {
784 btrfs_release_path(path);
785 swarn.path = path;
786 swarn.dev = dev;
787 iterate_extent_inodes(fs_info, found_key.objectid,
788 extent_item_pos, 1,
789 scrub_print_warning_inode, &swarn, false);
790 }
791
792 out:
793 btrfs_free_path(path);
794 }
795
796 static inline void scrub_get_recover(struct scrub_recover *recover)
797 {
798 refcount_inc(&recover->refs);
799 }
800
801 static inline void scrub_put_recover(struct btrfs_fs_info *fs_info,
802 struct scrub_recover *recover)
803 {
804 if (refcount_dec_and_test(&recover->refs)) {
805 btrfs_bio_counter_dec(fs_info);
806 btrfs_put_bbio(recover->bbio);
807 kfree(recover);
808 }
809 }
810
811 /*
812 * scrub_handle_errored_block gets called when either verification of the
813 * pages failed or the bio failed to read, e.g. with EIO. In the latter
814 * case, this function handles all pages in the bio, even though only one
815 * may be bad.
816 * The goal of this function is to repair the errored block by using the
817 * contents of one of the mirrors.
818 */
819 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
820 {
821 struct scrub_ctx *sctx = sblock_to_check->sctx;
822 struct btrfs_device *dev;
823 struct btrfs_fs_info *fs_info;
824 u64 logical;
825 unsigned int failed_mirror_index;
826 unsigned int is_metadata;
827 unsigned int have_csum;
828 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
829 struct scrub_block *sblock_bad;
830 int ret;
831 int mirror_index;
832 int page_num;
833 int success;
834 bool full_stripe_locked;
835 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
836 DEFAULT_RATELIMIT_BURST);
837
838 BUG_ON(sblock_to_check->page_count < 1);
839 fs_info = sctx->fs_info;
840 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) {
841 /*
842 * if we find an error in a super block, we just report it.
843 * They will get written with the next transaction commit
844 * anyway
845 */
846 spin_lock(&sctx->stat_lock);
847 ++sctx->stat.super_errors;
848 spin_unlock(&sctx->stat_lock);
849 return 0;
850 }
851 logical = sblock_to_check->pagev[0]->logical;
852 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1);
853 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1;
854 is_metadata = !(sblock_to_check->pagev[0]->flags &
855 BTRFS_EXTENT_FLAG_DATA);
856 have_csum = sblock_to_check->pagev[0]->have_csum;
857 dev = sblock_to_check->pagev[0]->dev;
858
859 /*
860 * For RAID5/6, race can happen for a different device scrub thread.
861 * For data corruption, Parity and Data threads will both try
862 * to recovery the data.
863 * Race can lead to doubly added csum error, or even unrecoverable
864 * error.
865 */
866 ret = lock_full_stripe(fs_info, logical, &full_stripe_locked);
867 if (ret < 0) {
868 spin_lock(&sctx->stat_lock);
869 if (ret == -ENOMEM)
870 sctx->stat.malloc_errors++;
871 sctx->stat.read_errors++;
872 sctx->stat.uncorrectable_errors++;
873 spin_unlock(&sctx->stat_lock);
874 return ret;
875 }
876
877 /*
878 * read all mirrors one after the other. This includes to
879 * re-read the extent or metadata block that failed (that was
880 * the cause that this fixup code is called) another time,
881 * page by page this time in order to know which pages
882 * caused I/O errors and which ones are good (for all mirrors).
883 * It is the goal to handle the situation when more than one
884 * mirror contains I/O errors, but the errors do not
885 * overlap, i.e. the data can be repaired by selecting the
886 * pages from those mirrors without I/O error on the
887 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
888 * would be that mirror #1 has an I/O error on the first page,
889 * the second page is good, and mirror #2 has an I/O error on
890 * the second page, but the first page is good.
891 * Then the first page of the first mirror can be repaired by
892 * taking the first page of the second mirror, and the
893 * second page of the second mirror can be repaired by
894 * copying the contents of the 2nd page of the 1st mirror.
895 * One more note: if the pages of one mirror contain I/O
896 * errors, the checksum cannot be verified. In order to get
897 * the best data for repairing, the first attempt is to find
898 * a mirror without I/O errors and with a validated checksum.
899 * Only if this is not possible, the pages are picked from
900 * mirrors with I/O errors without considering the checksum.
901 * If the latter is the case, at the end, the checksum of the
902 * repaired area is verified in order to correctly maintain
903 * the statistics.
904 */
905
906 sblocks_for_recheck = kcalloc(BTRFS_MAX_MIRRORS,
907 sizeof(*sblocks_for_recheck), GFP_NOFS);
908 if (!sblocks_for_recheck) {
909 spin_lock(&sctx->stat_lock);
910 sctx->stat.malloc_errors++;
911 sctx->stat.read_errors++;
912 sctx->stat.uncorrectable_errors++;
913 spin_unlock(&sctx->stat_lock);
914 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
915 goto out;
916 }
917
918 /* setup the context, map the logical blocks and alloc the pages */
919 ret = scrub_setup_recheck_block(sblock_to_check, sblocks_for_recheck);
920 if (ret) {
921 spin_lock(&sctx->stat_lock);
922 sctx->stat.read_errors++;
923 sctx->stat.uncorrectable_errors++;
924 spin_unlock(&sctx->stat_lock);
925 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
926 goto out;
927 }
928 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
929 sblock_bad = sblocks_for_recheck + failed_mirror_index;
930
931 /* build and submit the bios for the failed mirror, check checksums */
932 scrub_recheck_block(fs_info, sblock_bad, 1);
933
934 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
935 sblock_bad->no_io_error_seen) {
936 /*
937 * the error disappeared after reading page by page, or
938 * the area was part of a huge bio and other parts of the
939 * bio caused I/O errors, or the block layer merged several
940 * read requests into one and the error is caused by a
941 * different bio (usually one of the two latter cases is
942 * the cause)
943 */
944 spin_lock(&sctx->stat_lock);
945 sctx->stat.unverified_errors++;
946 sblock_to_check->data_corrected = 1;
947 spin_unlock(&sctx->stat_lock);
948
949 if (sctx->is_dev_replace)
950 scrub_write_block_to_dev_replace(sblock_bad);
951 goto out;
952 }
953
954 if (!sblock_bad->no_io_error_seen) {
955 spin_lock(&sctx->stat_lock);
956 sctx->stat.read_errors++;
957 spin_unlock(&sctx->stat_lock);
958 if (__ratelimit(&_rs))
959 scrub_print_warning("i/o error", sblock_to_check);
960 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
961 } else if (sblock_bad->checksum_error) {
962 spin_lock(&sctx->stat_lock);
963 sctx->stat.csum_errors++;
964 spin_unlock(&sctx->stat_lock);
965 if (__ratelimit(&_rs))
966 scrub_print_warning("checksum error", sblock_to_check);
967 btrfs_dev_stat_inc_and_print(dev,
968 BTRFS_DEV_STAT_CORRUPTION_ERRS);
969 } else if (sblock_bad->header_error) {
970 spin_lock(&sctx->stat_lock);
971 sctx->stat.verify_errors++;
972 spin_unlock(&sctx->stat_lock);
973 if (__ratelimit(&_rs))
974 scrub_print_warning("checksum/header error",
975 sblock_to_check);
976 if (sblock_bad->generation_error)
977 btrfs_dev_stat_inc_and_print(dev,
978 BTRFS_DEV_STAT_GENERATION_ERRS);
979 else
980 btrfs_dev_stat_inc_and_print(dev,
981 BTRFS_DEV_STAT_CORRUPTION_ERRS);
982 }
983
984 if (sctx->readonly) {
985 ASSERT(!sctx->is_dev_replace);
986 goto out;
987 }
988
989 /*
990 * now build and submit the bios for the other mirrors, check
991 * checksums.
992 * First try to pick the mirror which is completely without I/O
993 * errors and also does not have a checksum error.
994 * If one is found, and if a checksum is present, the full block
995 * that is known to contain an error is rewritten. Afterwards
996 * the block is known to be corrected.
997 * If a mirror is found which is completely correct, and no
998 * checksum is present, only those pages are rewritten that had
999 * an I/O error in the block to be repaired, since it cannot be
1000 * determined, which copy of the other pages is better (and it
1001 * could happen otherwise that a correct page would be
1002 * overwritten by a bad one).
1003 */
1004 for (mirror_index = 0; ;mirror_index++) {
1005 struct scrub_block *sblock_other;
1006
1007 if (mirror_index == failed_mirror_index)
1008 continue;
1009
1010 /* raid56's mirror can be more than BTRFS_MAX_MIRRORS */
1011 if (!scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1012 if (mirror_index >= BTRFS_MAX_MIRRORS)
1013 break;
1014 if (!sblocks_for_recheck[mirror_index].page_count)
1015 break;
1016
1017 sblock_other = sblocks_for_recheck + mirror_index;
1018 } else {
1019 struct scrub_recover *r = sblock_bad->pagev[0]->recover;
1020 int max_allowed = r->bbio->num_stripes -
1021 r->bbio->num_tgtdevs;
1022
1023 if (mirror_index >= max_allowed)
1024 break;
1025 if (!sblocks_for_recheck[1].page_count)
1026 break;
1027
1028 ASSERT(failed_mirror_index == 0);
1029 sblock_other = sblocks_for_recheck + 1;
1030 sblock_other->pagev[0]->mirror_num = 1 + mirror_index;
1031 }
1032
1033 /* build and submit the bios, check checksums */
1034 scrub_recheck_block(fs_info, sblock_other, 0);
1035
1036 if (!sblock_other->header_error &&
1037 !sblock_other->checksum_error &&
1038 sblock_other->no_io_error_seen) {
1039 if (sctx->is_dev_replace) {
1040 scrub_write_block_to_dev_replace(sblock_other);
1041 goto corrected_error;
1042 } else {
1043 ret = scrub_repair_block_from_good_copy(
1044 sblock_bad, sblock_other);
1045 if (!ret)
1046 goto corrected_error;
1047 }
1048 }
1049 }
1050
1051 if (sblock_bad->no_io_error_seen && !sctx->is_dev_replace)
1052 goto did_not_correct_error;
1053
1054 /*
1055 * In case of I/O errors in the area that is supposed to be
1056 * repaired, continue by picking good copies of those pages.
1057 * Select the good pages from mirrors to rewrite bad pages from
1058 * the area to fix. Afterwards verify the checksum of the block
1059 * that is supposed to be repaired. This verification step is
1060 * only done for the purpose of statistic counting and for the
1061 * final scrub report, whether errors remain.
1062 * A perfect algorithm could make use of the checksum and try
1063 * all possible combinations of pages from the different mirrors
1064 * until the checksum verification succeeds. For example, when
1065 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
1066 * of mirror #2 is readable but the final checksum test fails,
1067 * then the 2nd page of mirror #3 could be tried, whether now
1068 * the final checksum succeeds. But this would be a rare
1069 * exception and is therefore not implemented. At least it is
1070 * avoided that the good copy is overwritten.
1071 * A more useful improvement would be to pick the sectors
1072 * without I/O error based on sector sizes (512 bytes on legacy
1073 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
1074 * mirror could be repaired by taking 512 byte of a different
1075 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
1076 * area are unreadable.
1077 */
1078 success = 1;
1079 for (page_num = 0; page_num < sblock_bad->page_count;
1080 page_num++) {
1081 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1082 struct scrub_block *sblock_other = NULL;
1083
1084 /* skip no-io-error page in scrub */
1085 if (!page_bad->io_error && !sctx->is_dev_replace)
1086 continue;
1087
1088 if (scrub_is_page_on_raid56(sblock_bad->pagev[0])) {
1089 /*
1090 * In case of dev replace, if raid56 rebuild process
1091 * didn't work out correct data, then copy the content
1092 * in sblock_bad to make sure target device is identical
1093 * to source device, instead of writing garbage data in
1094 * sblock_for_recheck array to target device.
1095 */
1096 sblock_other = NULL;
1097 } else if (page_bad->io_error) {
1098 /* try to find no-io-error page in mirrors */
1099 for (mirror_index = 0;
1100 mirror_index < BTRFS_MAX_MIRRORS &&
1101 sblocks_for_recheck[mirror_index].page_count > 0;
1102 mirror_index++) {
1103 if (!sblocks_for_recheck[mirror_index].
1104 pagev[page_num]->io_error) {
1105 sblock_other = sblocks_for_recheck +
1106 mirror_index;
1107 break;
1108 }
1109 }
1110 if (!sblock_other)
1111 success = 0;
1112 }
1113
1114 if (sctx->is_dev_replace) {
1115 /*
1116 * did not find a mirror to fetch the page
1117 * from. scrub_write_page_to_dev_replace()
1118 * handles this case (page->io_error), by
1119 * filling the block with zeros before
1120 * submitting the write request
1121 */
1122 if (!sblock_other)
1123 sblock_other = sblock_bad;
1124
1125 if (scrub_write_page_to_dev_replace(sblock_other,
1126 page_num) != 0) {
1127 btrfs_dev_replace_stats_inc(
1128 &fs_info->dev_replace.num_write_errors);
1129 success = 0;
1130 }
1131 } else if (sblock_other) {
1132 ret = scrub_repair_page_from_good_copy(sblock_bad,
1133 sblock_other,
1134 page_num, 0);
1135 if (0 == ret)
1136 page_bad->io_error = 0;
1137 else
1138 success = 0;
1139 }
1140 }
1141
1142 if (success && !sctx->is_dev_replace) {
1143 if (is_metadata || have_csum) {
1144 /*
1145 * need to verify the checksum now that all
1146 * sectors on disk are repaired (the write
1147 * request for data to be repaired is on its way).
1148 * Just be lazy and use scrub_recheck_block()
1149 * which re-reads the data before the checksum
1150 * is verified, but most likely the data comes out
1151 * of the page cache.
1152 */
1153 scrub_recheck_block(fs_info, sblock_bad, 1);
1154 if (!sblock_bad->header_error &&
1155 !sblock_bad->checksum_error &&
1156 sblock_bad->no_io_error_seen)
1157 goto corrected_error;
1158 else
1159 goto did_not_correct_error;
1160 } else {
1161 corrected_error:
1162 spin_lock(&sctx->stat_lock);
1163 sctx->stat.corrected_errors++;
1164 sblock_to_check->data_corrected = 1;
1165 spin_unlock(&sctx->stat_lock);
1166 btrfs_err_rl_in_rcu(fs_info,
1167 "fixed up error at logical %llu on dev %s",
1168 logical, rcu_str_deref(dev->name));
1169 }
1170 } else {
1171 did_not_correct_error:
1172 spin_lock(&sctx->stat_lock);
1173 sctx->stat.uncorrectable_errors++;
1174 spin_unlock(&sctx->stat_lock);
1175 btrfs_err_rl_in_rcu(fs_info,
1176 "unable to fixup (regular) error at logical %llu on dev %s",
1177 logical, rcu_str_deref(dev->name));
1178 }
1179
1180 out:
1181 if (sblocks_for_recheck) {
1182 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
1183 mirror_index++) {
1184 struct scrub_block *sblock = sblocks_for_recheck +
1185 mirror_index;
1186 struct scrub_recover *recover;
1187 int page_index;
1188
1189 for (page_index = 0; page_index < sblock->page_count;
1190 page_index++) {
1191 sblock->pagev[page_index]->sblock = NULL;
1192 recover = sblock->pagev[page_index]->recover;
1193 if (recover) {
1194 scrub_put_recover(fs_info, recover);
1195 sblock->pagev[page_index]->recover =
1196 NULL;
1197 }
1198 scrub_page_put(sblock->pagev[page_index]);
1199 }
1200 }
1201 kfree(sblocks_for_recheck);
1202 }
1203
1204 ret = unlock_full_stripe(fs_info, logical, full_stripe_locked);
1205 if (ret < 0)
1206 return ret;
1207 return 0;
1208 }
1209
1210 static inline int scrub_nr_raid_mirrors(struct btrfs_bio *bbio)
1211 {
1212 if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID5)
1213 return 2;
1214 else if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID6)
1215 return 3;
1216 else
1217 return (int)bbio->num_stripes;
1218 }
1219
1220 static inline void scrub_stripe_index_and_offset(u64 logical, u64 map_type,
1221 u64 *raid_map,
1222 u64 mapped_length,
1223 int nstripes, int mirror,
1224 int *stripe_index,
1225 u64 *stripe_offset)
1226 {
1227 int i;
1228
1229 if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
1230 /* RAID5/6 */
1231 for (i = 0; i < nstripes; i++) {
1232 if (raid_map[i] == RAID6_Q_STRIPE ||
1233 raid_map[i] == RAID5_P_STRIPE)
1234 continue;
1235
1236 if (logical >= raid_map[i] &&
1237 logical < raid_map[i] + mapped_length)
1238 break;
1239 }
1240
1241 *stripe_index = i;
1242 *stripe_offset = logical - raid_map[i];
1243 } else {
1244 /* The other RAID type */
1245 *stripe_index = mirror;
1246 *stripe_offset = 0;
1247 }
1248 }
1249
1250 static int scrub_setup_recheck_block(struct scrub_block *original_sblock,
1251 struct scrub_block *sblocks_for_recheck)
1252 {
1253 struct scrub_ctx *sctx = original_sblock->sctx;
1254 struct btrfs_fs_info *fs_info = sctx->fs_info;
1255 u64 length = original_sblock->page_count * PAGE_SIZE;
1256 u64 logical = original_sblock->pagev[0]->logical;
1257 u64 generation = original_sblock->pagev[0]->generation;
1258 u64 flags = original_sblock->pagev[0]->flags;
1259 u64 have_csum = original_sblock->pagev[0]->have_csum;
1260 struct scrub_recover *recover;
1261 struct btrfs_bio *bbio;
1262 u64 sublen;
1263 u64 mapped_length;
1264 u64 stripe_offset;
1265 int stripe_index;
1266 int page_index = 0;
1267 int mirror_index;
1268 int nmirrors;
1269 int ret;
1270
1271 /*
1272 * note: the two members refs and outstanding_pages
1273 * are not used (and not set) in the blocks that are used for
1274 * the recheck procedure
1275 */
1276
1277 while (length > 0) {
1278 sublen = min_t(u64, length, PAGE_SIZE);
1279 mapped_length = sublen;
1280 bbio = NULL;
1281
1282 /*
1283 * with a length of PAGE_SIZE, each returned stripe
1284 * represents one mirror
1285 */
1286 btrfs_bio_counter_inc_blocked(fs_info);
1287 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS,
1288 logical, &mapped_length, &bbio);
1289 if (ret || !bbio || mapped_length < sublen) {
1290 btrfs_put_bbio(bbio);
1291 btrfs_bio_counter_dec(fs_info);
1292 return -EIO;
1293 }
1294
1295 recover = kzalloc(sizeof(struct scrub_recover), GFP_NOFS);
1296 if (!recover) {
1297 btrfs_put_bbio(bbio);
1298 btrfs_bio_counter_dec(fs_info);
1299 return -ENOMEM;
1300 }
1301
1302 refcount_set(&recover->refs, 1);
1303 recover->bbio = bbio;
1304 recover->map_length = mapped_length;
1305
1306 BUG_ON(page_index >= SCRUB_MAX_PAGES_PER_BLOCK);
1307
1308 nmirrors = min(scrub_nr_raid_mirrors(bbio), BTRFS_MAX_MIRRORS);
1309
1310 for (mirror_index = 0; mirror_index < nmirrors;
1311 mirror_index++) {
1312 struct scrub_block *sblock;
1313 struct scrub_page *page;
1314
1315 sblock = sblocks_for_recheck + mirror_index;
1316 sblock->sctx = sctx;
1317
1318 page = kzalloc(sizeof(*page), GFP_NOFS);
1319 if (!page) {
1320 leave_nomem:
1321 spin_lock(&sctx->stat_lock);
1322 sctx->stat.malloc_errors++;
1323 spin_unlock(&sctx->stat_lock);
1324 scrub_put_recover(fs_info, recover);
1325 return -ENOMEM;
1326 }
1327 scrub_page_get(page);
1328 sblock->pagev[page_index] = page;
1329 page->sblock = sblock;
1330 page->flags = flags;
1331 page->generation = generation;
1332 page->logical = logical;
1333 page->have_csum = have_csum;
1334 if (have_csum)
1335 memcpy(page->csum,
1336 original_sblock->pagev[0]->csum,
1337 sctx->csum_size);
1338
1339 scrub_stripe_index_and_offset(logical,
1340 bbio->map_type,
1341 bbio->raid_map,
1342 mapped_length,
1343 bbio->num_stripes -
1344 bbio->num_tgtdevs,
1345 mirror_index,
1346 &stripe_index,
1347 &stripe_offset);
1348 page->physical = bbio->stripes[stripe_index].physical +
1349 stripe_offset;
1350 page->dev = bbio->stripes[stripe_index].dev;
1351
1352 BUG_ON(page_index >= original_sblock->page_count);
1353 page->physical_for_dev_replace =
1354 original_sblock->pagev[page_index]->
1355 physical_for_dev_replace;
1356 /* for missing devices, dev->bdev is NULL */
1357 page->mirror_num = mirror_index + 1;
1358 sblock->page_count++;
1359 page->page = alloc_page(GFP_NOFS);
1360 if (!page->page)
1361 goto leave_nomem;
1362
1363 scrub_get_recover(recover);
1364 page->recover = recover;
1365 }
1366 scrub_put_recover(fs_info, recover);
1367 length -= sublen;
1368 logical += sublen;
1369 page_index++;
1370 }
1371
1372 return 0;
1373 }
1374
1375 static void scrub_bio_wait_endio(struct bio *bio)
1376 {
1377 complete(bio->bi_private);
1378 }
1379
1380 static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info,
1381 struct bio *bio,
1382 struct scrub_page *page)
1383 {
1384 DECLARE_COMPLETION_ONSTACK(done);
1385 int ret;
1386 int mirror_num;
1387
1388 bio->bi_iter.bi_sector = page->logical >> 9;
1389 bio->bi_private = &done;
1390 bio->bi_end_io = scrub_bio_wait_endio;
1391
1392 mirror_num = page->sblock->pagev[0]->mirror_num;
1393 ret = raid56_parity_recover(fs_info, bio, page->recover->bbio,
1394 page->recover->map_length,
1395 mirror_num, 0);
1396 if (ret)
1397 return ret;
1398
1399 wait_for_completion_io(&done);
1400 return blk_status_to_errno(bio->bi_status);
1401 }
1402
1403 static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info,
1404 struct scrub_block *sblock)
1405 {
1406 struct scrub_page *first_page = sblock->pagev[0];
1407 struct bio *bio;
1408 int page_num;
1409
1410 /* All pages in sblock belong to the same stripe on the same device. */
1411 ASSERT(first_page->dev);
1412 if (!first_page->dev->bdev)
1413 goto out;
1414
1415 bio = btrfs_io_bio_alloc(BIO_MAX_PAGES);
1416 bio_set_dev(bio, first_page->dev->bdev);
1417
1418 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1419 struct scrub_page *page = sblock->pagev[page_num];
1420
1421 WARN_ON(!page->page);
1422 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1423 }
1424
1425 if (scrub_submit_raid56_bio_wait(fs_info, bio, first_page)) {
1426 bio_put(bio);
1427 goto out;
1428 }
1429
1430 bio_put(bio);
1431
1432 scrub_recheck_block_checksum(sblock);
1433
1434 return;
1435 out:
1436 for (page_num = 0; page_num < sblock->page_count; page_num++)
1437 sblock->pagev[page_num]->io_error = 1;
1438
1439 sblock->no_io_error_seen = 0;
1440 }
1441
1442 /*
1443 * this function will check the on disk data for checksum errors, header
1444 * errors and read I/O errors. If any I/O errors happen, the exact pages
1445 * which are errored are marked as being bad. The goal is to enable scrub
1446 * to take those pages that are not errored from all the mirrors so that
1447 * the pages that are errored in the just handled mirror can be repaired.
1448 */
1449 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
1450 struct scrub_block *sblock,
1451 int retry_failed_mirror)
1452 {
1453 int page_num;
1454
1455 sblock->no_io_error_seen = 1;
1456
1457 /* short cut for raid56 */
1458 if (!retry_failed_mirror && scrub_is_page_on_raid56(sblock->pagev[0]))
1459 return scrub_recheck_block_on_raid56(fs_info, sblock);
1460
1461 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1462 struct bio *bio;
1463 struct scrub_page *page = sblock->pagev[page_num];
1464
1465 if (page->dev->bdev == NULL) {
1466 page->io_error = 1;
1467 sblock->no_io_error_seen = 0;
1468 continue;
1469 }
1470
1471 WARN_ON(!page->page);
1472 bio = btrfs_io_bio_alloc(1);
1473 bio_set_dev(bio, page->dev->bdev);
1474
1475 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1476 bio->bi_iter.bi_sector = page->physical >> 9;
1477 bio->bi_opf = REQ_OP_READ;
1478
1479 if (btrfsic_submit_bio_wait(bio)) {
1480 page->io_error = 1;
1481 sblock->no_io_error_seen = 0;
1482 }
1483
1484 bio_put(bio);
1485 }
1486
1487 if (sblock->no_io_error_seen)
1488 scrub_recheck_block_checksum(sblock);
1489 }
1490
1491 static inline int scrub_check_fsid(u8 fsid[],
1492 struct scrub_page *spage)
1493 {
1494 struct btrfs_fs_devices *fs_devices = spage->dev->fs_devices;
1495 int ret;
1496
1497 ret = memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE);
1498 return !ret;
1499 }
1500
1501 static void scrub_recheck_block_checksum(struct scrub_block *sblock)
1502 {
1503 sblock->header_error = 0;
1504 sblock->checksum_error = 0;
1505 sblock->generation_error = 0;
1506
1507 if (sblock->pagev[0]->flags & BTRFS_EXTENT_FLAG_DATA)
1508 scrub_checksum_data(sblock);
1509 else
1510 scrub_checksum_tree_block(sblock);
1511 }
1512
1513 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1514 struct scrub_block *sblock_good)
1515 {
1516 int page_num;
1517 int ret = 0;
1518
1519 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1520 int ret_sub;
1521
1522 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1523 sblock_good,
1524 page_num, 1);
1525 if (ret_sub)
1526 ret = ret_sub;
1527 }
1528
1529 return ret;
1530 }
1531
1532 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1533 struct scrub_block *sblock_good,
1534 int page_num, int force_write)
1535 {
1536 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1537 struct scrub_page *page_good = sblock_good->pagev[page_num];
1538 struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info;
1539
1540 BUG_ON(page_bad->page == NULL);
1541 BUG_ON(page_good->page == NULL);
1542 if (force_write || sblock_bad->header_error ||
1543 sblock_bad->checksum_error || page_bad->io_error) {
1544 struct bio *bio;
1545 int ret;
1546
1547 if (!page_bad->dev->bdev) {
1548 btrfs_warn_rl(fs_info,
1549 "scrub_repair_page_from_good_copy(bdev == NULL) is unexpected");
1550 return -EIO;
1551 }
1552
1553 bio = btrfs_io_bio_alloc(1);
1554 bio_set_dev(bio, page_bad->dev->bdev);
1555 bio->bi_iter.bi_sector = page_bad->physical >> 9;
1556 bio->bi_opf = REQ_OP_WRITE;
1557
1558 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1559 if (PAGE_SIZE != ret) {
1560 bio_put(bio);
1561 return -EIO;
1562 }
1563
1564 if (btrfsic_submit_bio_wait(bio)) {
1565 btrfs_dev_stat_inc_and_print(page_bad->dev,
1566 BTRFS_DEV_STAT_WRITE_ERRS);
1567 btrfs_dev_replace_stats_inc(
1568 &fs_info->dev_replace.num_write_errors);
1569 bio_put(bio);
1570 return -EIO;
1571 }
1572 bio_put(bio);
1573 }
1574
1575 return 0;
1576 }
1577
1578 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
1579 {
1580 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
1581 int page_num;
1582
1583 /*
1584 * This block is used for the check of the parity on the source device,
1585 * so the data needn't be written into the destination device.
1586 */
1587 if (sblock->sparity)
1588 return;
1589
1590 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1591 int ret;
1592
1593 ret = scrub_write_page_to_dev_replace(sblock, page_num);
1594 if (ret)
1595 btrfs_dev_replace_stats_inc(
1596 &fs_info->dev_replace.num_write_errors);
1597 }
1598 }
1599
1600 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
1601 int page_num)
1602 {
1603 struct scrub_page *spage = sblock->pagev[page_num];
1604
1605 BUG_ON(spage->page == NULL);
1606 if (spage->io_error) {
1607 void *mapped_buffer = kmap_atomic(spage->page);
1608
1609 clear_page(mapped_buffer);
1610 flush_dcache_page(spage->page);
1611 kunmap_atomic(mapped_buffer);
1612 }
1613 return scrub_add_page_to_wr_bio(sblock->sctx, spage);
1614 }
1615
1616 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
1617 struct scrub_page *spage)
1618 {
1619 struct scrub_bio *sbio;
1620 int ret;
1621
1622 mutex_lock(&sctx->wr_lock);
1623 again:
1624 if (!sctx->wr_curr_bio) {
1625 sctx->wr_curr_bio = kzalloc(sizeof(*sctx->wr_curr_bio),
1626 GFP_KERNEL);
1627 if (!sctx->wr_curr_bio) {
1628 mutex_unlock(&sctx->wr_lock);
1629 return -ENOMEM;
1630 }
1631 sctx->wr_curr_bio->sctx = sctx;
1632 sctx->wr_curr_bio->page_count = 0;
1633 }
1634 sbio = sctx->wr_curr_bio;
1635 if (sbio->page_count == 0) {
1636 struct bio *bio;
1637
1638 sbio->physical = spage->physical_for_dev_replace;
1639 sbio->logical = spage->logical;
1640 sbio->dev = sctx->wr_tgtdev;
1641 bio = sbio->bio;
1642 if (!bio) {
1643 bio = btrfs_io_bio_alloc(sctx->pages_per_wr_bio);
1644 sbio->bio = bio;
1645 }
1646
1647 bio->bi_private = sbio;
1648 bio->bi_end_io = scrub_wr_bio_end_io;
1649 bio_set_dev(bio, sbio->dev->bdev);
1650 bio->bi_iter.bi_sector = sbio->physical >> 9;
1651 bio->bi_opf = REQ_OP_WRITE;
1652 sbio->status = 0;
1653 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1654 spage->physical_for_dev_replace ||
1655 sbio->logical + sbio->page_count * PAGE_SIZE !=
1656 spage->logical) {
1657 scrub_wr_submit(sctx);
1658 goto again;
1659 }
1660
1661 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1662 if (ret != PAGE_SIZE) {
1663 if (sbio->page_count < 1) {
1664 bio_put(sbio->bio);
1665 sbio->bio = NULL;
1666 mutex_unlock(&sctx->wr_lock);
1667 return -EIO;
1668 }
1669 scrub_wr_submit(sctx);
1670 goto again;
1671 }
1672
1673 sbio->pagev[sbio->page_count] = spage;
1674 scrub_page_get(spage);
1675 sbio->page_count++;
1676 if (sbio->page_count == sctx->pages_per_wr_bio)
1677 scrub_wr_submit(sctx);
1678 mutex_unlock(&sctx->wr_lock);
1679
1680 return 0;
1681 }
1682
1683 static void scrub_wr_submit(struct scrub_ctx *sctx)
1684 {
1685 struct scrub_bio *sbio;
1686
1687 if (!sctx->wr_curr_bio)
1688 return;
1689
1690 sbio = sctx->wr_curr_bio;
1691 sctx->wr_curr_bio = NULL;
1692 WARN_ON(!sbio->bio->bi_disk);
1693 scrub_pending_bio_inc(sctx);
1694 /* process all writes in a single worker thread. Then the block layer
1695 * orders the requests before sending them to the driver which
1696 * doubled the write performance on spinning disks when measured
1697 * with Linux 3.5 */
1698 btrfsic_submit_bio(sbio->bio);
1699 }
1700
1701 static void scrub_wr_bio_end_io(struct bio *bio)
1702 {
1703 struct scrub_bio *sbio = bio->bi_private;
1704 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
1705
1706 sbio->status = bio->bi_status;
1707 sbio->bio = bio;
1708
1709 btrfs_init_work(&sbio->work, btrfs_scrubwrc_helper,
1710 scrub_wr_bio_end_io_worker, NULL, NULL);
1711 btrfs_queue_work(fs_info->scrub_wr_completion_workers, &sbio->work);
1712 }
1713
1714 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work)
1715 {
1716 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1717 struct scrub_ctx *sctx = sbio->sctx;
1718 int i;
1719
1720 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO);
1721 if (sbio->status) {
1722 struct btrfs_dev_replace *dev_replace =
1723 &sbio->sctx->fs_info->dev_replace;
1724
1725 for (i = 0; i < sbio->page_count; i++) {
1726 struct scrub_page *spage = sbio->pagev[i];
1727
1728 spage->io_error = 1;
1729 btrfs_dev_replace_stats_inc(&dev_replace->
1730 num_write_errors);
1731 }
1732 }
1733
1734 for (i = 0; i < sbio->page_count; i++)
1735 scrub_page_put(sbio->pagev[i]);
1736
1737 bio_put(sbio->bio);
1738 kfree(sbio);
1739 scrub_pending_bio_dec(sctx);
1740 }
1741
1742 static int scrub_checksum(struct scrub_block *sblock)
1743 {
1744 u64 flags;
1745 int ret;
1746
1747 /*
1748 * No need to initialize these stats currently,
1749 * because this function only use return value
1750 * instead of these stats value.
1751 *
1752 * Todo:
1753 * always use stats
1754 */
1755 sblock->header_error = 0;
1756 sblock->generation_error = 0;
1757 sblock->checksum_error = 0;
1758
1759 WARN_ON(sblock->page_count < 1);
1760 flags = sblock->pagev[0]->flags;
1761 ret = 0;
1762 if (flags & BTRFS_EXTENT_FLAG_DATA)
1763 ret = scrub_checksum_data(sblock);
1764 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1765 ret = scrub_checksum_tree_block(sblock);
1766 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1767 (void)scrub_checksum_super(sblock);
1768 else
1769 WARN_ON(1);
1770 if (ret)
1771 scrub_handle_errored_block(sblock);
1772
1773 return ret;
1774 }
1775
1776 static int scrub_checksum_data(struct scrub_block *sblock)
1777 {
1778 struct scrub_ctx *sctx = sblock->sctx;
1779 u8 csum[BTRFS_CSUM_SIZE];
1780 u8 *on_disk_csum;
1781 struct page *page;
1782 void *buffer;
1783 u32 crc = ~(u32)0;
1784 u64 len;
1785 int index;
1786
1787 BUG_ON(sblock->page_count < 1);
1788 if (!sblock->pagev[0]->have_csum)
1789 return 0;
1790
1791 on_disk_csum = sblock->pagev[0]->csum;
1792 page = sblock->pagev[0]->page;
1793 buffer = kmap_atomic(page);
1794
1795 len = sctx->fs_info->sectorsize;
1796 index = 0;
1797 for (;;) {
1798 u64 l = min_t(u64, len, PAGE_SIZE);
1799
1800 crc = btrfs_csum_data(buffer, crc, l);
1801 kunmap_atomic(buffer);
1802 len -= l;
1803 if (len == 0)
1804 break;
1805 index++;
1806 BUG_ON(index >= sblock->page_count);
1807 BUG_ON(!sblock->pagev[index]->page);
1808 page = sblock->pagev[index]->page;
1809 buffer = kmap_atomic(page);
1810 }
1811
1812 btrfs_csum_final(crc, csum);
1813 if (memcmp(csum, on_disk_csum, sctx->csum_size))
1814 sblock->checksum_error = 1;
1815
1816 return sblock->checksum_error;
1817 }
1818
1819 static int scrub_checksum_tree_block(struct scrub_block *sblock)
1820 {
1821 struct scrub_ctx *sctx = sblock->sctx;
1822 struct btrfs_header *h;
1823 struct btrfs_fs_info *fs_info = sctx->fs_info;
1824 u8 calculated_csum[BTRFS_CSUM_SIZE];
1825 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1826 struct page *page;
1827 void *mapped_buffer;
1828 u64 mapped_size;
1829 void *p;
1830 u32 crc = ~(u32)0;
1831 u64 len;
1832 int index;
1833
1834 BUG_ON(sblock->page_count < 1);
1835 page = sblock->pagev[0]->page;
1836 mapped_buffer = kmap_atomic(page);
1837 h = (struct btrfs_header *)mapped_buffer;
1838 memcpy(on_disk_csum, h->csum, sctx->csum_size);
1839
1840 /*
1841 * we don't use the getter functions here, as we
1842 * a) don't have an extent buffer and
1843 * b) the page is already kmapped
1844 */
1845 if (sblock->pagev[0]->logical != btrfs_stack_header_bytenr(h))
1846 sblock->header_error = 1;
1847
1848 if (sblock->pagev[0]->generation != btrfs_stack_header_generation(h)) {
1849 sblock->header_error = 1;
1850 sblock->generation_error = 1;
1851 }
1852
1853 if (!scrub_check_fsid(h->fsid, sblock->pagev[0]))
1854 sblock->header_error = 1;
1855
1856 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1857 BTRFS_UUID_SIZE))
1858 sblock->header_error = 1;
1859
1860 len = sctx->fs_info->nodesize - BTRFS_CSUM_SIZE;
1861 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1862 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1863 index = 0;
1864 for (;;) {
1865 u64 l = min_t(u64, len, mapped_size);
1866
1867 crc = btrfs_csum_data(p, crc, l);
1868 kunmap_atomic(mapped_buffer);
1869 len -= l;
1870 if (len == 0)
1871 break;
1872 index++;
1873 BUG_ON(index >= sblock->page_count);
1874 BUG_ON(!sblock->pagev[index]->page);
1875 page = sblock->pagev[index]->page;
1876 mapped_buffer = kmap_atomic(page);
1877 mapped_size = PAGE_SIZE;
1878 p = mapped_buffer;
1879 }
1880
1881 btrfs_csum_final(crc, calculated_csum);
1882 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1883 sblock->checksum_error = 1;
1884
1885 return sblock->header_error || sblock->checksum_error;
1886 }
1887
1888 static int scrub_checksum_super(struct scrub_block *sblock)
1889 {
1890 struct btrfs_super_block *s;
1891 struct scrub_ctx *sctx = sblock->sctx;
1892 u8 calculated_csum[BTRFS_CSUM_SIZE];
1893 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1894 struct page *page;
1895 void *mapped_buffer;
1896 u64 mapped_size;
1897 void *p;
1898 u32 crc = ~(u32)0;
1899 int fail_gen = 0;
1900 int fail_cor = 0;
1901 u64 len;
1902 int index;
1903
1904 BUG_ON(sblock->page_count < 1);
1905 page = sblock->pagev[0]->page;
1906 mapped_buffer = kmap_atomic(page);
1907 s = (struct btrfs_super_block *)mapped_buffer;
1908 memcpy(on_disk_csum, s->csum, sctx->csum_size);
1909
1910 if (sblock->pagev[0]->logical != btrfs_super_bytenr(s))
1911 ++fail_cor;
1912
1913 if (sblock->pagev[0]->generation != btrfs_super_generation(s))
1914 ++fail_gen;
1915
1916 if (!scrub_check_fsid(s->fsid, sblock->pagev[0]))
1917 ++fail_cor;
1918
1919 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1920 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1921 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1922 index = 0;
1923 for (;;) {
1924 u64 l = min_t(u64, len, mapped_size);
1925
1926 crc = btrfs_csum_data(p, crc, l);
1927 kunmap_atomic(mapped_buffer);
1928 len -= l;
1929 if (len == 0)
1930 break;
1931 index++;
1932 BUG_ON(index >= sblock->page_count);
1933 BUG_ON(!sblock->pagev[index]->page);
1934 page = sblock->pagev[index]->page;
1935 mapped_buffer = kmap_atomic(page);
1936 mapped_size = PAGE_SIZE;
1937 p = mapped_buffer;
1938 }
1939
1940 btrfs_csum_final(crc, calculated_csum);
1941 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1942 ++fail_cor;
1943
1944 if (fail_cor + fail_gen) {
1945 /*
1946 * if we find an error in a super block, we just report it.
1947 * They will get written with the next transaction commit
1948 * anyway
1949 */
1950 spin_lock(&sctx->stat_lock);
1951 ++sctx->stat.super_errors;
1952 spin_unlock(&sctx->stat_lock);
1953 if (fail_cor)
1954 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1955 BTRFS_DEV_STAT_CORRUPTION_ERRS);
1956 else
1957 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1958 BTRFS_DEV_STAT_GENERATION_ERRS);
1959 }
1960
1961 return fail_cor + fail_gen;
1962 }
1963
1964 static void scrub_block_get(struct scrub_block *sblock)
1965 {
1966 refcount_inc(&sblock->refs);
1967 }
1968
1969 static void scrub_block_put(struct scrub_block *sblock)
1970 {
1971 if (refcount_dec_and_test(&sblock->refs)) {
1972 int i;
1973
1974 if (sblock->sparity)
1975 scrub_parity_put(sblock->sparity);
1976
1977 for (i = 0; i < sblock->page_count; i++)
1978 scrub_page_put(sblock->pagev[i]);
1979 kfree(sblock);
1980 }
1981 }
1982
1983 static void scrub_page_get(struct scrub_page *spage)
1984 {
1985 atomic_inc(&spage->refs);
1986 }
1987
1988 static void scrub_page_put(struct scrub_page *spage)
1989 {
1990 if (atomic_dec_and_test(&spage->refs)) {
1991 if (spage->page)
1992 __free_page(spage->page);
1993 kfree(spage);
1994 }
1995 }
1996
1997 static void scrub_submit(struct scrub_ctx *sctx)
1998 {
1999 struct scrub_bio *sbio;
2000
2001 if (sctx->curr == -1)
2002 return;
2003
2004 sbio = sctx->bios[sctx->curr];
2005 sctx->curr = -1;
2006 scrub_pending_bio_inc(sctx);
2007 btrfsic_submit_bio(sbio->bio);
2008 }
2009
2010 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
2011 struct scrub_page *spage)
2012 {
2013 struct scrub_block *sblock = spage->sblock;
2014 struct scrub_bio *sbio;
2015 int ret;
2016
2017 again:
2018 /*
2019 * grab a fresh bio or wait for one to become available
2020 */
2021 while (sctx->curr == -1) {
2022 spin_lock(&sctx->list_lock);
2023 sctx->curr = sctx->first_free;
2024 if (sctx->curr != -1) {
2025 sctx->first_free = sctx->bios[sctx->curr]->next_free;
2026 sctx->bios[sctx->curr]->next_free = -1;
2027 sctx->bios[sctx->curr]->page_count = 0;
2028 spin_unlock(&sctx->list_lock);
2029 } else {
2030 spin_unlock(&sctx->list_lock);
2031 wait_event(sctx->list_wait, sctx->first_free != -1);
2032 }
2033 }
2034 sbio = sctx->bios[sctx->curr];
2035 if (sbio->page_count == 0) {
2036 struct bio *bio;
2037
2038 sbio->physical = spage->physical;
2039 sbio->logical = spage->logical;
2040 sbio->dev = spage->dev;
2041 bio = sbio->bio;
2042 if (!bio) {
2043 bio = btrfs_io_bio_alloc(sctx->pages_per_rd_bio);
2044 sbio->bio = bio;
2045 }
2046
2047 bio->bi_private = sbio;
2048 bio->bi_end_io = scrub_bio_end_io;
2049 bio_set_dev(bio, sbio->dev->bdev);
2050 bio->bi_iter.bi_sector = sbio->physical >> 9;
2051 bio->bi_opf = REQ_OP_READ;
2052 sbio->status = 0;
2053 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
2054 spage->physical ||
2055 sbio->logical + sbio->page_count * PAGE_SIZE !=
2056 spage->logical ||
2057 sbio->dev != spage->dev) {
2058 scrub_submit(sctx);
2059 goto again;
2060 }
2061
2062 sbio->pagev[sbio->page_count] = spage;
2063 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
2064 if (ret != PAGE_SIZE) {
2065 if (sbio->page_count < 1) {
2066 bio_put(sbio->bio);
2067 sbio->bio = NULL;
2068 return -EIO;
2069 }
2070 scrub_submit(sctx);
2071 goto again;
2072 }
2073
2074 scrub_block_get(sblock); /* one for the page added to the bio */
2075 atomic_inc(&sblock->outstanding_pages);
2076 sbio->page_count++;
2077 if (sbio->page_count == sctx->pages_per_rd_bio)
2078 scrub_submit(sctx);
2079
2080 return 0;
2081 }
2082
2083 static void scrub_missing_raid56_end_io(struct bio *bio)
2084 {
2085 struct scrub_block *sblock = bio->bi_private;
2086 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info;
2087
2088 if (bio->bi_status)
2089 sblock->no_io_error_seen = 0;
2090
2091 bio_put(bio);
2092
2093 btrfs_queue_work(fs_info->scrub_workers, &sblock->work);
2094 }
2095
2096 static void scrub_missing_raid56_worker(struct btrfs_work *work)
2097 {
2098 struct scrub_block *sblock = container_of(work, struct scrub_block, work);
2099 struct scrub_ctx *sctx = sblock->sctx;
2100 struct btrfs_fs_info *fs_info = sctx->fs_info;
2101 u64 logical;
2102 struct btrfs_device *dev;
2103
2104 logical = sblock->pagev[0]->logical;
2105 dev = sblock->pagev[0]->dev;
2106
2107 if (sblock->no_io_error_seen)
2108 scrub_recheck_block_checksum(sblock);
2109
2110 if (!sblock->no_io_error_seen) {
2111 spin_lock(&sctx->stat_lock);
2112 sctx->stat.read_errors++;
2113 spin_unlock(&sctx->stat_lock);
2114 btrfs_err_rl_in_rcu(fs_info,
2115 "IO error rebuilding logical %llu for dev %s",
2116 logical, rcu_str_deref(dev->name));
2117 } else if (sblock->header_error || sblock->checksum_error) {
2118 spin_lock(&sctx->stat_lock);
2119 sctx->stat.uncorrectable_errors++;
2120 spin_unlock(&sctx->stat_lock);
2121 btrfs_err_rl_in_rcu(fs_info,
2122 "failed to rebuild valid logical %llu for dev %s",
2123 logical, rcu_str_deref(dev->name));
2124 } else {
2125 scrub_write_block_to_dev_replace(sblock);
2126 }
2127
2128 scrub_block_put(sblock);
2129
2130 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2131 mutex_lock(&sctx->wr_lock);
2132 scrub_wr_submit(sctx);
2133 mutex_unlock(&sctx->wr_lock);
2134 }
2135
2136 scrub_pending_bio_dec(sctx);
2137 }
2138
2139 static void scrub_missing_raid56_pages(struct scrub_block *sblock)
2140 {
2141 struct scrub_ctx *sctx = sblock->sctx;
2142 struct btrfs_fs_info *fs_info = sctx->fs_info;
2143 u64 length = sblock->page_count * PAGE_SIZE;
2144 u64 logical = sblock->pagev[0]->logical;
2145 struct btrfs_bio *bbio = NULL;
2146 struct bio *bio;
2147 struct btrfs_raid_bio *rbio;
2148 int ret;
2149 int i;
2150
2151 btrfs_bio_counter_inc_blocked(fs_info);
2152 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
2153 &length, &bbio);
2154 if (ret || !bbio || !bbio->raid_map)
2155 goto bbio_out;
2156
2157 if (WARN_ON(!sctx->is_dev_replace ||
2158 !(bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK))) {
2159 /*
2160 * We shouldn't be scrubbing a missing device. Even for dev
2161 * replace, we should only get here for RAID 5/6. We either
2162 * managed to mount something with no mirrors remaining or
2163 * there's a bug in scrub_remap_extent()/btrfs_map_block().
2164 */
2165 goto bbio_out;
2166 }
2167
2168 bio = btrfs_io_bio_alloc(0);
2169 bio->bi_iter.bi_sector = logical >> 9;
2170 bio->bi_private = sblock;
2171 bio->bi_end_io = scrub_missing_raid56_end_io;
2172
2173 rbio = raid56_alloc_missing_rbio(fs_info, bio, bbio, length);
2174 if (!rbio)
2175 goto rbio_out;
2176
2177 for (i = 0; i < sblock->page_count; i++) {
2178 struct scrub_page *spage = sblock->pagev[i];
2179
2180 raid56_add_scrub_pages(rbio, spage->page, spage->logical);
2181 }
2182
2183 btrfs_init_work(&sblock->work, btrfs_scrub_helper,
2184 scrub_missing_raid56_worker, NULL, NULL);
2185 scrub_block_get(sblock);
2186 scrub_pending_bio_inc(sctx);
2187 raid56_submit_missing_rbio(rbio);
2188 return;
2189
2190 rbio_out:
2191 bio_put(bio);
2192 bbio_out:
2193 btrfs_bio_counter_dec(fs_info);
2194 btrfs_put_bbio(bbio);
2195 spin_lock(&sctx->stat_lock);
2196 sctx->stat.malloc_errors++;
2197 spin_unlock(&sctx->stat_lock);
2198 }
2199
2200 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
2201 u64 physical, struct btrfs_device *dev, u64 flags,
2202 u64 gen, int mirror_num, u8 *csum, int force,
2203 u64 physical_for_dev_replace)
2204 {
2205 struct scrub_block *sblock;
2206 int index;
2207
2208 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2209 if (!sblock) {
2210 spin_lock(&sctx->stat_lock);
2211 sctx->stat.malloc_errors++;
2212 spin_unlock(&sctx->stat_lock);
2213 return -ENOMEM;
2214 }
2215
2216 /* one ref inside this function, plus one for each page added to
2217 * a bio later on */
2218 refcount_set(&sblock->refs, 1);
2219 sblock->sctx = sctx;
2220 sblock->no_io_error_seen = 1;
2221
2222 for (index = 0; len > 0; index++) {
2223 struct scrub_page *spage;
2224 u64 l = min_t(u64, len, PAGE_SIZE);
2225
2226 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2227 if (!spage) {
2228 leave_nomem:
2229 spin_lock(&sctx->stat_lock);
2230 sctx->stat.malloc_errors++;
2231 spin_unlock(&sctx->stat_lock);
2232 scrub_block_put(sblock);
2233 return -ENOMEM;
2234 }
2235 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2236 scrub_page_get(spage);
2237 sblock->pagev[index] = spage;
2238 spage->sblock = sblock;
2239 spage->dev = dev;
2240 spage->flags = flags;
2241 spage->generation = gen;
2242 spage->logical = logical;
2243 spage->physical = physical;
2244 spage->physical_for_dev_replace = physical_for_dev_replace;
2245 spage->mirror_num = mirror_num;
2246 if (csum) {
2247 spage->have_csum = 1;
2248 memcpy(spage->csum, csum, sctx->csum_size);
2249 } else {
2250 spage->have_csum = 0;
2251 }
2252 sblock->page_count++;
2253 spage->page = alloc_page(GFP_KERNEL);
2254 if (!spage->page)
2255 goto leave_nomem;
2256 len -= l;
2257 logical += l;
2258 physical += l;
2259 physical_for_dev_replace += l;
2260 }
2261
2262 WARN_ON(sblock->page_count == 0);
2263 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2264 /*
2265 * This case should only be hit for RAID 5/6 device replace. See
2266 * the comment in scrub_missing_raid56_pages() for details.
2267 */
2268 scrub_missing_raid56_pages(sblock);
2269 } else {
2270 for (index = 0; index < sblock->page_count; index++) {
2271 struct scrub_page *spage = sblock->pagev[index];
2272 int ret;
2273
2274 ret = scrub_add_page_to_rd_bio(sctx, spage);
2275 if (ret) {
2276 scrub_block_put(sblock);
2277 return ret;
2278 }
2279 }
2280
2281 if (force)
2282 scrub_submit(sctx);
2283 }
2284
2285 /* last one frees, either here or in bio completion for last page */
2286 scrub_block_put(sblock);
2287 return 0;
2288 }
2289
2290 static void scrub_bio_end_io(struct bio *bio)
2291 {
2292 struct scrub_bio *sbio = bio->bi_private;
2293 struct btrfs_fs_info *fs_info = sbio->dev->fs_info;
2294
2295 sbio->status = bio->bi_status;
2296 sbio->bio = bio;
2297
2298 btrfs_queue_work(fs_info->scrub_workers, &sbio->work);
2299 }
2300
2301 static void scrub_bio_end_io_worker(struct btrfs_work *work)
2302 {
2303 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
2304 struct scrub_ctx *sctx = sbio->sctx;
2305 int i;
2306
2307 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO);
2308 if (sbio->status) {
2309 for (i = 0; i < sbio->page_count; i++) {
2310 struct scrub_page *spage = sbio->pagev[i];
2311
2312 spage->io_error = 1;
2313 spage->sblock->no_io_error_seen = 0;
2314 }
2315 }
2316
2317 /* now complete the scrub_block items that have all pages completed */
2318 for (i = 0; i < sbio->page_count; i++) {
2319 struct scrub_page *spage = sbio->pagev[i];
2320 struct scrub_block *sblock = spage->sblock;
2321
2322 if (atomic_dec_and_test(&sblock->outstanding_pages))
2323 scrub_block_complete(sblock);
2324 scrub_block_put(sblock);
2325 }
2326
2327 bio_put(sbio->bio);
2328 sbio->bio = NULL;
2329 spin_lock(&sctx->list_lock);
2330 sbio->next_free = sctx->first_free;
2331 sctx->first_free = sbio->index;
2332 spin_unlock(&sctx->list_lock);
2333
2334 if (sctx->is_dev_replace && sctx->flush_all_writes) {
2335 mutex_lock(&sctx->wr_lock);
2336 scrub_wr_submit(sctx);
2337 mutex_unlock(&sctx->wr_lock);
2338 }
2339
2340 scrub_pending_bio_dec(sctx);
2341 }
2342
2343 static inline void __scrub_mark_bitmap(struct scrub_parity *sparity,
2344 unsigned long *bitmap,
2345 u64 start, u64 len)
2346 {
2347 u64 offset;
2348 u64 nsectors64;
2349 u32 nsectors;
2350 int sectorsize = sparity->sctx->fs_info->sectorsize;
2351
2352 if (len >= sparity->stripe_len) {
2353 bitmap_set(bitmap, 0, sparity->nsectors);
2354 return;
2355 }
2356
2357 start -= sparity->logic_start;
2358 start = div64_u64_rem(start, sparity->stripe_len, &offset);
2359 offset = div_u64(offset, sectorsize);
2360 nsectors64 = div_u64(len, sectorsize);
2361
2362 ASSERT(nsectors64 < UINT_MAX);
2363 nsectors = (u32)nsectors64;
2364
2365 if (offset + nsectors <= sparity->nsectors) {
2366 bitmap_set(bitmap, offset, nsectors);
2367 return;
2368 }
2369
2370 bitmap_set(bitmap, offset, sparity->nsectors - offset);
2371 bitmap_set(bitmap, 0, nsectors - (sparity->nsectors - offset));
2372 }
2373
2374 static inline void scrub_parity_mark_sectors_error(struct scrub_parity *sparity,
2375 u64 start, u64 len)
2376 {
2377 __scrub_mark_bitmap(sparity, sparity->ebitmap, start, len);
2378 }
2379
2380 static inline void scrub_parity_mark_sectors_data(struct scrub_parity *sparity,
2381 u64 start, u64 len)
2382 {
2383 __scrub_mark_bitmap(sparity, sparity->dbitmap, start, len);
2384 }
2385
2386 static void scrub_block_complete(struct scrub_block *sblock)
2387 {
2388 int corrupted = 0;
2389
2390 if (!sblock->no_io_error_seen) {
2391 corrupted = 1;
2392 scrub_handle_errored_block(sblock);
2393 } else {
2394 /*
2395 * if has checksum error, write via repair mechanism in
2396 * dev replace case, otherwise write here in dev replace
2397 * case.
2398 */
2399 corrupted = scrub_checksum(sblock);
2400 if (!corrupted && sblock->sctx->is_dev_replace)
2401 scrub_write_block_to_dev_replace(sblock);
2402 }
2403
2404 if (sblock->sparity && corrupted && !sblock->data_corrected) {
2405 u64 start = sblock->pagev[0]->logical;
2406 u64 end = sblock->pagev[sblock->page_count - 1]->logical +
2407 PAGE_SIZE;
2408
2409 scrub_parity_mark_sectors_error(sblock->sparity,
2410 start, end - start);
2411 }
2412 }
2413
2414 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum)
2415 {
2416 struct btrfs_ordered_sum *sum = NULL;
2417 unsigned long index;
2418 unsigned long num_sectors;
2419
2420 while (!list_empty(&sctx->csum_list)) {
2421 sum = list_first_entry(&sctx->csum_list,
2422 struct btrfs_ordered_sum, list);
2423 if (sum->bytenr > logical)
2424 return 0;
2425 if (sum->bytenr + sum->len > logical)
2426 break;
2427
2428 ++sctx->stat.csum_discards;
2429 list_del(&sum->list);
2430 kfree(sum);
2431 sum = NULL;
2432 }
2433 if (!sum)
2434 return 0;
2435
2436 index = div_u64(logical - sum->bytenr, sctx->fs_info->sectorsize);
2437 ASSERT(index < UINT_MAX);
2438
2439 num_sectors = sum->len / sctx->fs_info->sectorsize;
2440 memcpy(csum, sum->sums + index, sctx->csum_size);
2441 if (index == num_sectors - 1) {
2442 list_del(&sum->list);
2443 kfree(sum);
2444 }
2445 return 1;
2446 }
2447
2448 /* scrub extent tries to collect up to 64 kB for each bio */
2449 static int scrub_extent(struct scrub_ctx *sctx, struct map_lookup *map,
2450 u64 logical, u64 len,
2451 u64 physical, struct btrfs_device *dev, u64 flags,
2452 u64 gen, int mirror_num, u64 physical_for_dev_replace)
2453 {
2454 int ret;
2455 u8 csum[BTRFS_CSUM_SIZE];
2456 u32 blocksize;
2457
2458 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2459 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2460 blocksize = map->stripe_len;
2461 else
2462 blocksize = sctx->fs_info->sectorsize;
2463 spin_lock(&sctx->stat_lock);
2464 sctx->stat.data_extents_scrubbed++;
2465 sctx->stat.data_bytes_scrubbed += len;
2466 spin_unlock(&sctx->stat_lock);
2467 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2468 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK)
2469 blocksize = map->stripe_len;
2470 else
2471 blocksize = sctx->fs_info->nodesize;
2472 spin_lock(&sctx->stat_lock);
2473 sctx->stat.tree_extents_scrubbed++;
2474 sctx->stat.tree_bytes_scrubbed += len;
2475 spin_unlock(&sctx->stat_lock);
2476 } else {
2477 blocksize = sctx->fs_info->sectorsize;
2478 WARN_ON(1);
2479 }
2480
2481 while (len) {
2482 u64 l = min_t(u64, len, blocksize);
2483 int have_csum = 0;
2484
2485 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2486 /* push csums to sbio */
2487 have_csum = scrub_find_csum(sctx, logical, csum);
2488 if (have_csum == 0)
2489 ++sctx->stat.no_csum;
2490 }
2491 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen,
2492 mirror_num, have_csum ? csum : NULL, 0,
2493 physical_for_dev_replace);
2494 if (ret)
2495 return ret;
2496 len -= l;
2497 logical += l;
2498 physical += l;
2499 physical_for_dev_replace += l;
2500 }
2501 return 0;
2502 }
2503
2504 static int scrub_pages_for_parity(struct scrub_parity *sparity,
2505 u64 logical, u64 len,
2506 u64 physical, struct btrfs_device *dev,
2507 u64 flags, u64 gen, int mirror_num, u8 *csum)
2508 {
2509 struct scrub_ctx *sctx = sparity->sctx;
2510 struct scrub_block *sblock;
2511 int index;
2512
2513 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL);
2514 if (!sblock) {
2515 spin_lock(&sctx->stat_lock);
2516 sctx->stat.malloc_errors++;
2517 spin_unlock(&sctx->stat_lock);
2518 return -ENOMEM;
2519 }
2520
2521 /* one ref inside this function, plus one for each page added to
2522 * a bio later on */
2523 refcount_set(&sblock->refs, 1);
2524 sblock->sctx = sctx;
2525 sblock->no_io_error_seen = 1;
2526 sblock->sparity = sparity;
2527 scrub_parity_get(sparity);
2528
2529 for (index = 0; len > 0; index++) {
2530 struct scrub_page *spage;
2531 u64 l = min_t(u64, len, PAGE_SIZE);
2532
2533 spage = kzalloc(sizeof(*spage), GFP_KERNEL);
2534 if (!spage) {
2535 leave_nomem:
2536 spin_lock(&sctx->stat_lock);
2537 sctx->stat.malloc_errors++;
2538 spin_unlock(&sctx->stat_lock);
2539 scrub_block_put(sblock);
2540 return -ENOMEM;
2541 }
2542 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2543 /* For scrub block */
2544 scrub_page_get(spage);
2545 sblock->pagev[index] = spage;
2546 /* For scrub parity */
2547 scrub_page_get(spage);
2548 list_add_tail(&spage->list, &sparity->spages);
2549 spage->sblock = sblock;
2550 spage->dev = dev;
2551 spage->flags = flags;
2552 spage->generation = gen;
2553 spage->logical = logical;
2554 spage->physical = physical;
2555 spage->mirror_num = mirror_num;
2556 if (csum) {
2557 spage->have_csum = 1;
2558 memcpy(spage->csum, csum, sctx->csum_size);
2559 } else {
2560 spage->have_csum = 0;
2561 }
2562 sblock->page_count++;
2563 spage->page = alloc_page(GFP_KERNEL);
2564 if (!spage->page)
2565 goto leave_nomem;
2566 len -= l;
2567 logical += l;
2568 physical += l;
2569 }
2570
2571 WARN_ON(sblock->page_count == 0);
2572 for (index = 0; index < sblock->page_count; index++) {
2573 struct scrub_page *spage = sblock->pagev[index];
2574 int ret;
2575
2576 ret = scrub_add_page_to_rd_bio(sctx, spage);
2577 if (ret) {
2578 scrub_block_put(sblock);
2579 return ret;
2580 }
2581 }
2582
2583 /* last one frees, either here or in bio completion for last page */
2584 scrub_block_put(sblock);
2585 return 0;
2586 }
2587
2588 static int scrub_extent_for_parity(struct scrub_parity *sparity,
2589 u64 logical, u64 len,
2590 u64 physical, struct btrfs_device *dev,
2591 u64 flags, u64 gen, int mirror_num)
2592 {
2593 struct scrub_ctx *sctx = sparity->sctx;
2594 int ret;
2595 u8 csum[BTRFS_CSUM_SIZE];
2596 u32 blocksize;
2597
2598 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) {
2599 scrub_parity_mark_sectors_error(sparity, logical, len);
2600 return 0;
2601 }
2602
2603 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2604 blocksize = sparity->stripe_len;
2605 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2606 blocksize = sparity->stripe_len;
2607 } else {
2608 blocksize = sctx->fs_info->sectorsize;
2609 WARN_ON(1);
2610 }
2611
2612 while (len) {
2613 u64 l = min_t(u64, len, blocksize);
2614 int have_csum = 0;
2615
2616 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2617 /* push csums to sbio */
2618 have_csum = scrub_find_csum(sctx, logical, csum);
2619 if (have_csum == 0)
2620 goto skip;
2621 }
2622 ret = scrub_pages_for_parity(sparity, logical, l, physical, dev,
2623 flags, gen, mirror_num,
2624 have_csum ? csum : NULL);
2625 if (ret)
2626 return ret;
2627 skip:
2628 len -= l;
2629 logical += l;
2630 physical += l;
2631 }
2632 return 0;
2633 }
2634
2635 /*
2636 * Given a physical address, this will calculate it's
2637 * logical offset. if this is a parity stripe, it will return
2638 * the most left data stripe's logical offset.
2639 *
2640 * return 0 if it is a data stripe, 1 means parity stripe.
2641 */
2642 static int get_raid56_logic_offset(u64 physical, int num,
2643 struct map_lookup *map, u64 *offset,
2644 u64 *stripe_start)
2645 {
2646 int i;
2647 int j = 0;
2648 u64 stripe_nr;
2649 u64 last_offset;
2650 u32 stripe_index;
2651 u32 rot;
2652
2653 last_offset = (physical - map->stripes[num].physical) *
2654 nr_data_stripes(map);
2655 if (stripe_start)
2656 *stripe_start = last_offset;
2657
2658 *offset = last_offset;
2659 for (i = 0; i < nr_data_stripes(map); i++) {
2660 *offset = last_offset + i * map->stripe_len;
2661
2662 stripe_nr = div64_u64(*offset, map->stripe_len);
2663 stripe_nr = div_u64(stripe_nr, nr_data_stripes(map));
2664
2665 /* Work out the disk rotation on this stripe-set */
2666 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot);
2667 /* calculate which stripe this data locates */
2668 rot += i;
2669 stripe_index = rot % map->num_stripes;
2670 if (stripe_index == num)
2671 return 0;
2672 if (stripe_index < num)
2673 j++;
2674 }
2675 *offset = last_offset + j * map->stripe_len;
2676 return 1;
2677 }
2678
2679 static void scrub_free_parity(struct scrub_parity *sparity)
2680 {
2681 struct scrub_ctx *sctx = sparity->sctx;
2682 struct scrub_page *curr, *next;
2683 int nbits;
2684
2685 nbits = bitmap_weight(sparity->ebitmap, sparity->nsectors);
2686 if (nbits) {
2687 spin_lock(&sctx->stat_lock);
2688 sctx->stat.read_errors += nbits;
2689 sctx->stat.uncorrectable_errors += nbits;
2690 spin_unlock(&sctx->stat_lock);
2691 }
2692
2693 list_for_each_entry_safe(curr, next, &sparity->spages, list) {
2694 list_del_init(&curr->list);
2695 scrub_page_put(curr);
2696 }
2697
2698 kfree(sparity);
2699 }
2700
2701 static void scrub_parity_bio_endio_worker(struct btrfs_work *work)
2702 {
2703 struct scrub_parity *sparity = container_of(work, struct scrub_parity,
2704 work);
2705 struct scrub_ctx *sctx = sparity->sctx;
2706
2707 scrub_free_parity(sparity);
2708 scrub_pending_bio_dec(sctx);
2709 }
2710
2711 static void scrub_parity_bio_endio(struct bio *bio)
2712 {
2713 struct scrub_parity *sparity = (struct scrub_parity *)bio->bi_private;
2714 struct btrfs_fs_info *fs_info = sparity->sctx->fs_info;
2715
2716 if (bio->bi_status)
2717 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2718 sparity->nsectors);
2719
2720 bio_put(bio);
2721
2722 btrfs_init_work(&sparity->work, btrfs_scrubparity_helper,
2723 scrub_parity_bio_endio_worker, NULL, NULL);
2724 btrfs_queue_work(fs_info->scrub_parity_workers, &sparity->work);
2725 }
2726
2727 static void scrub_parity_check_and_repair(struct scrub_parity *sparity)
2728 {
2729 struct scrub_ctx *sctx = sparity->sctx;
2730 struct btrfs_fs_info *fs_info = sctx->fs_info;
2731 struct bio *bio;
2732 struct btrfs_raid_bio *rbio;
2733 struct btrfs_bio *bbio = NULL;
2734 u64 length;
2735 int ret;
2736
2737 if (!bitmap_andnot(sparity->dbitmap, sparity->dbitmap, sparity->ebitmap,
2738 sparity->nsectors))
2739 goto out;
2740
2741 length = sparity->logic_end - sparity->logic_start;
2742
2743 btrfs_bio_counter_inc_blocked(fs_info);
2744 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start,
2745 &length, &bbio);
2746 if (ret || !bbio || !bbio->raid_map)
2747 goto bbio_out;
2748
2749 bio = btrfs_io_bio_alloc(0);
2750 bio->bi_iter.bi_sector = sparity->logic_start >> 9;
2751 bio->bi_private = sparity;
2752 bio->bi_end_io = scrub_parity_bio_endio;
2753
2754 rbio = raid56_parity_alloc_scrub_rbio(fs_info, bio, bbio,
2755 length, sparity->scrub_dev,
2756 sparity->dbitmap,
2757 sparity->nsectors);
2758 if (!rbio)
2759 goto rbio_out;
2760
2761 scrub_pending_bio_inc(sctx);
2762 raid56_parity_submit_scrub_rbio(rbio);
2763 return;
2764
2765 rbio_out:
2766 bio_put(bio);
2767 bbio_out:
2768 btrfs_bio_counter_dec(fs_info);
2769 btrfs_put_bbio(bbio);
2770 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap,
2771 sparity->nsectors);
2772 spin_lock(&sctx->stat_lock);
2773 sctx->stat.malloc_errors++;
2774 spin_unlock(&sctx->stat_lock);
2775 out:
2776 scrub_free_parity(sparity);
2777 }
2778
2779 static inline int scrub_calc_parity_bitmap_len(int nsectors)
2780 {
2781 return DIV_ROUND_UP(nsectors, BITS_PER_LONG) * sizeof(long);
2782 }
2783
2784 static void scrub_parity_get(struct scrub_parity *sparity)
2785 {
2786 refcount_inc(&sparity->refs);
2787 }
2788
2789 static void scrub_parity_put(struct scrub_parity *sparity)
2790 {
2791 if (!refcount_dec_and_test(&sparity->refs))
2792 return;
2793
2794 scrub_parity_check_and_repair(sparity);
2795 }
2796
2797 static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx,
2798 struct map_lookup *map,
2799 struct btrfs_device *sdev,
2800 struct btrfs_path *path,
2801 u64 logic_start,
2802 u64 logic_end)
2803 {
2804 struct btrfs_fs_info *fs_info = sctx->fs_info;
2805 struct btrfs_root *root = fs_info->extent_root;
2806 struct btrfs_root *csum_root = fs_info->csum_root;
2807 struct btrfs_extent_item *extent;
2808 struct btrfs_bio *bbio = NULL;
2809 u64 flags;
2810 int ret;
2811 int slot;
2812 struct extent_buffer *l;
2813 struct btrfs_key key;
2814 u64 generation;
2815 u64 extent_logical;
2816 u64 extent_physical;
2817 u64 extent_len;
2818 u64 mapped_length;
2819 struct btrfs_device *extent_dev;
2820 struct scrub_parity *sparity;
2821 int nsectors;
2822 int bitmap_len;
2823 int extent_mirror_num;
2824 int stop_loop = 0;
2825
2826 nsectors = div_u64(map->stripe_len, fs_info->sectorsize);
2827 bitmap_len = scrub_calc_parity_bitmap_len(nsectors);
2828 sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len,
2829 GFP_NOFS);
2830 if (!sparity) {
2831 spin_lock(&sctx->stat_lock);
2832 sctx->stat.malloc_errors++;
2833 spin_unlock(&sctx->stat_lock);
2834 return -ENOMEM;
2835 }
2836
2837 sparity->stripe_len = map->stripe_len;
2838 sparity->nsectors = nsectors;
2839 sparity->sctx = sctx;
2840 sparity->scrub_dev = sdev;
2841 sparity->logic_start = logic_start;
2842 sparity->logic_end = logic_end;
2843 refcount_set(&sparity->refs, 1);
2844 INIT_LIST_HEAD(&sparity->spages);
2845 sparity->dbitmap = sparity->bitmap;
2846 sparity->ebitmap = (void *)sparity->bitmap + bitmap_len;
2847
2848 ret = 0;
2849 while (logic_start < logic_end) {
2850 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
2851 key.type = BTRFS_METADATA_ITEM_KEY;
2852 else
2853 key.type = BTRFS_EXTENT_ITEM_KEY;
2854 key.objectid = logic_start;
2855 key.offset = (u64)-1;
2856
2857 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2858 if (ret < 0)
2859 goto out;
2860
2861 if (ret > 0) {
2862 ret = btrfs_previous_extent_item(root, path, 0);
2863 if (ret < 0)
2864 goto out;
2865 if (ret > 0) {
2866 btrfs_release_path(path);
2867 ret = btrfs_search_slot(NULL, root, &key,
2868 path, 0, 0);
2869 if (ret < 0)
2870 goto out;
2871 }
2872 }
2873
2874 stop_loop = 0;
2875 while (1) {
2876 u64 bytes;
2877
2878 l = path->nodes[0];
2879 slot = path->slots[0];
2880 if (slot >= btrfs_header_nritems(l)) {
2881 ret = btrfs_next_leaf(root, path);
2882 if (ret == 0)
2883 continue;
2884 if (ret < 0)
2885 goto out;
2886
2887 stop_loop = 1;
2888 break;
2889 }
2890 btrfs_item_key_to_cpu(l, &key, slot);
2891
2892 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
2893 key.type != BTRFS_METADATA_ITEM_KEY)
2894 goto next;
2895
2896 if (key.type == BTRFS_METADATA_ITEM_KEY)
2897 bytes = fs_info->nodesize;
2898 else
2899 bytes = key.offset;
2900
2901 if (key.objectid + bytes <= logic_start)
2902 goto next;
2903
2904 if (key.objectid >= logic_end) {
2905 stop_loop = 1;
2906 break;
2907 }
2908
2909 while (key.objectid >= logic_start + map->stripe_len)
2910 logic_start += map->stripe_len;
2911
2912 extent = btrfs_item_ptr(l, slot,
2913 struct btrfs_extent_item);
2914 flags = btrfs_extent_flags(l, extent);
2915 generation = btrfs_extent_generation(l, extent);
2916
2917 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
2918 (key.objectid < logic_start ||
2919 key.objectid + bytes >
2920 logic_start + map->stripe_len)) {
2921 btrfs_err(fs_info,
2922 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
2923 key.objectid, logic_start);
2924 spin_lock(&sctx->stat_lock);
2925 sctx->stat.uncorrectable_errors++;
2926 spin_unlock(&sctx->stat_lock);
2927 goto next;
2928 }
2929 again:
2930 extent_logical = key.objectid;
2931 extent_len = bytes;
2932
2933 if (extent_logical < logic_start) {
2934 extent_len -= logic_start - extent_logical;
2935 extent_logical = logic_start;
2936 }
2937
2938 if (extent_logical + extent_len >
2939 logic_start + map->stripe_len)
2940 extent_len = logic_start + map->stripe_len -
2941 extent_logical;
2942
2943 scrub_parity_mark_sectors_data(sparity, extent_logical,
2944 extent_len);
2945
2946 mapped_length = extent_len;
2947 bbio = NULL;
2948 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ,
2949 extent_logical, &mapped_length, &bbio,
2950 0);
2951 if (!ret) {
2952 if (!bbio || mapped_length < extent_len)
2953 ret = -EIO;
2954 }
2955 if (ret) {
2956 btrfs_put_bbio(bbio);
2957 goto out;
2958 }
2959 extent_physical = bbio->stripes[0].physical;
2960 extent_mirror_num = bbio->mirror_num;
2961 extent_dev = bbio->stripes[0].dev;
2962 btrfs_put_bbio(bbio);
2963
2964 ret = btrfs_lookup_csums_range(csum_root,
2965 extent_logical,
2966 extent_logical + extent_len - 1,
2967 &sctx->csum_list, 1);
2968 if (ret)
2969 goto out;
2970
2971 ret = scrub_extent_for_parity(sparity, extent_logical,
2972 extent_len,
2973 extent_physical,
2974 extent_dev, flags,
2975 generation,
2976 extent_mirror_num);
2977
2978 scrub_free_csums(sctx);
2979
2980 if (ret)
2981 goto out;
2982
2983 if (extent_logical + extent_len <
2984 key.objectid + bytes) {
2985 logic_start += map->stripe_len;
2986
2987 if (logic_start >= logic_end) {
2988 stop_loop = 1;
2989 break;
2990 }
2991
2992 if (logic_start < key.objectid + bytes) {
2993 cond_resched();
2994 goto again;
2995 }
2996 }
2997 next:
2998 path->slots[0]++;
2999 }
3000
3001 btrfs_release_path(path);
3002
3003 if (stop_loop)
3004 break;
3005
3006 logic_start += map->stripe_len;
3007 }
3008 out:
3009 if (ret < 0)
3010 scrub_parity_mark_sectors_error(sparity, logic_start,
3011 logic_end - logic_start);
3012 scrub_parity_put(sparity);
3013 scrub_submit(sctx);
3014 mutex_lock(&sctx->wr_lock);
3015 scrub_wr_submit(sctx);
3016 mutex_unlock(&sctx->wr_lock);
3017
3018 btrfs_release_path(path);
3019 return ret < 0 ? ret : 0;
3020 }
3021
3022 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
3023 struct map_lookup *map,
3024 struct btrfs_device *scrub_dev,
3025 int num, u64 base, u64 length,
3026 int is_dev_replace)
3027 {
3028 struct btrfs_path *path, *ppath;
3029 struct btrfs_fs_info *fs_info = sctx->fs_info;
3030 struct btrfs_root *root = fs_info->extent_root;
3031 struct btrfs_root *csum_root = fs_info->csum_root;
3032 struct btrfs_extent_item *extent;
3033 struct blk_plug plug;
3034 u64 flags;
3035 int ret;
3036 int slot;
3037 u64 nstripes;
3038 struct extent_buffer *l;
3039 u64 physical;
3040 u64 logical;
3041 u64 logic_end;
3042 u64 physical_end;
3043 u64 generation;
3044 int mirror_num;
3045 struct reada_control *reada1;
3046 struct reada_control *reada2;
3047 struct btrfs_key key;
3048 struct btrfs_key key_end;
3049 u64 increment = map->stripe_len;
3050 u64 offset;
3051 u64 extent_logical;
3052 u64 extent_physical;
3053 u64 extent_len;
3054 u64 stripe_logical;
3055 u64 stripe_end;
3056 struct btrfs_device *extent_dev;
3057 int extent_mirror_num;
3058 int stop_loop = 0;
3059
3060 physical = map->stripes[num].physical;
3061 offset = 0;
3062 nstripes = div64_u64(length, map->stripe_len);
3063 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
3064 offset = map->stripe_len * num;
3065 increment = map->stripe_len * map->num_stripes;
3066 mirror_num = 1;
3067 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
3068 int factor = map->num_stripes / map->sub_stripes;
3069 offset = map->stripe_len * (num / map->sub_stripes);
3070 increment = map->stripe_len * factor;
3071 mirror_num = num % map->sub_stripes + 1;
3072 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
3073 increment = map->stripe_len;
3074 mirror_num = num % map->num_stripes + 1;
3075 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
3076 increment = map->stripe_len;
3077 mirror_num = num % map->num_stripes + 1;
3078 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3079 get_raid56_logic_offset(physical, num, map, &offset, NULL);
3080 increment = map->stripe_len * nr_data_stripes(map);
3081 mirror_num = 1;
3082 } else {
3083 increment = map->stripe_len;
3084 mirror_num = 1;
3085 }
3086
3087 path = btrfs_alloc_path();
3088 if (!path)
3089 return -ENOMEM;
3090
3091 ppath = btrfs_alloc_path();
3092 if (!ppath) {
3093 btrfs_free_path(path);
3094 return -ENOMEM;
3095 }
3096
3097 /*
3098 * work on commit root. The related disk blocks are static as
3099 * long as COW is applied. This means, it is save to rewrite
3100 * them to repair disk errors without any race conditions
3101 */
3102 path->search_commit_root = 1;
3103 path->skip_locking = 1;
3104
3105 ppath->search_commit_root = 1;
3106 ppath->skip_locking = 1;
3107 /*
3108 * trigger the readahead for extent tree csum tree and wait for
3109 * completion. During readahead, the scrub is officially paused
3110 * to not hold off transaction commits
3111 */
3112 logical = base + offset;
3113 physical_end = physical + nstripes * map->stripe_len;
3114 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3115 get_raid56_logic_offset(physical_end, num,
3116 map, &logic_end, NULL);
3117 logic_end += base;
3118 } else {
3119 logic_end = logical + increment * nstripes;
3120 }
3121 wait_event(sctx->list_wait,
3122 atomic_read(&sctx->bios_in_flight) == 0);
3123 scrub_blocked_if_needed(fs_info);
3124
3125 /* FIXME it might be better to start readahead at commit root */
3126 key.objectid = logical;
3127 key.type = BTRFS_EXTENT_ITEM_KEY;
3128 key.offset = (u64)0;
3129 key_end.objectid = logic_end;
3130 key_end.type = BTRFS_METADATA_ITEM_KEY;
3131 key_end.offset = (u64)-1;
3132 reada1 = btrfs_reada_add(root, &key, &key_end);
3133
3134 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3135 key.type = BTRFS_EXTENT_CSUM_KEY;
3136 key.offset = logical;
3137 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
3138 key_end.type = BTRFS_EXTENT_CSUM_KEY;
3139 key_end.offset = logic_end;
3140 reada2 = btrfs_reada_add(csum_root, &key, &key_end);
3141
3142 if (!IS_ERR(reada1))
3143 btrfs_reada_wait(reada1);
3144 if (!IS_ERR(reada2))
3145 btrfs_reada_wait(reada2);
3146
3147
3148 /*
3149 * collect all data csums for the stripe to avoid seeking during
3150 * the scrub. This might currently (crc32) end up to be about 1MB
3151 */
3152 blk_start_plug(&plug);
3153
3154 /*
3155 * now find all extents for each stripe and scrub them
3156 */
3157 ret = 0;
3158 while (physical < physical_end) {
3159 /*
3160 * canceled?
3161 */
3162 if (atomic_read(&fs_info->scrub_cancel_req) ||
3163 atomic_read(&sctx->cancel_req)) {
3164 ret = -ECANCELED;
3165 goto out;
3166 }
3167 /*
3168 * check to see if we have to pause
3169 */
3170 if (atomic_read(&fs_info->scrub_pause_req)) {
3171 /* push queued extents */
3172 sctx->flush_all_writes = true;
3173 scrub_submit(sctx);
3174 mutex_lock(&sctx->wr_lock);
3175 scrub_wr_submit(sctx);
3176 mutex_unlock(&sctx->wr_lock);
3177 wait_event(sctx->list_wait,
3178 atomic_read(&sctx->bios_in_flight) == 0);
3179 sctx->flush_all_writes = false;
3180 scrub_blocked_if_needed(fs_info);
3181 }
3182
3183 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3184 ret = get_raid56_logic_offset(physical, num, map,
3185 &logical,
3186 &stripe_logical);
3187 logical += base;
3188 if (ret) {
3189 /* it is parity strip */
3190 stripe_logical += base;
3191 stripe_end = stripe_logical + increment;
3192 ret = scrub_raid56_parity(sctx, map, scrub_dev,
3193 ppath, stripe_logical,
3194 stripe_end);
3195 if (ret)
3196 goto out;
3197 goto skip;
3198 }
3199 }
3200
3201 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA))
3202 key.type = BTRFS_METADATA_ITEM_KEY;
3203 else
3204 key.type = BTRFS_EXTENT_ITEM_KEY;
3205 key.objectid = logical;
3206 key.offset = (u64)-1;
3207
3208 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3209 if (ret < 0)
3210 goto out;
3211
3212 if (ret > 0) {
3213 ret = btrfs_previous_extent_item(root, path, 0);
3214 if (ret < 0)
3215 goto out;
3216 if (ret > 0) {
3217 /* there's no smaller item, so stick with the
3218 * larger one */
3219 btrfs_release_path(path);
3220 ret = btrfs_search_slot(NULL, root, &key,
3221 path, 0, 0);
3222 if (ret < 0)
3223 goto out;
3224 }
3225 }
3226
3227 stop_loop = 0;
3228 while (1) {
3229 u64 bytes;
3230
3231 l = path->nodes[0];
3232 slot = path->slots[0];
3233 if (slot >= btrfs_header_nritems(l)) {
3234 ret = btrfs_next_leaf(root, path);
3235 if (ret == 0)
3236 continue;
3237 if (ret < 0)
3238 goto out;
3239
3240 stop_loop = 1;
3241 break;
3242 }
3243 btrfs_item_key_to_cpu(l, &key, slot);
3244
3245 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
3246 key.type != BTRFS_METADATA_ITEM_KEY)
3247 goto next;
3248
3249 if (key.type == BTRFS_METADATA_ITEM_KEY)
3250 bytes = fs_info->nodesize;
3251 else
3252 bytes = key.offset;
3253
3254 if (key.objectid + bytes <= logical)
3255 goto next;
3256
3257 if (key.objectid >= logical + map->stripe_len) {
3258 /* out of this device extent */
3259 if (key.objectid >= logic_end)
3260 stop_loop = 1;
3261 break;
3262 }
3263
3264 extent = btrfs_item_ptr(l, slot,
3265 struct btrfs_extent_item);
3266 flags = btrfs_extent_flags(l, extent);
3267 generation = btrfs_extent_generation(l, extent);
3268
3269 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) &&
3270 (key.objectid < logical ||
3271 key.objectid + bytes >
3272 logical + map->stripe_len)) {
3273 btrfs_err(fs_info,
3274 "scrub: tree block %llu spanning stripes, ignored. logical=%llu",
3275 key.objectid, logical);
3276 spin_lock(&sctx->stat_lock);
3277 sctx->stat.uncorrectable_errors++;
3278 spin_unlock(&sctx->stat_lock);
3279 goto next;
3280 }
3281
3282 again:
3283 extent_logical = key.objectid;
3284 extent_len = bytes;
3285
3286 /*
3287 * trim extent to this stripe
3288 */
3289 if (extent_logical < logical) {
3290 extent_len -= logical - extent_logical;
3291 extent_logical = logical;
3292 }
3293 if (extent_logical + extent_len >
3294 logical + map->stripe_len) {
3295 extent_len = logical + map->stripe_len -
3296 extent_logical;
3297 }
3298
3299 extent_physical = extent_logical - logical + physical;
3300 extent_dev = scrub_dev;
3301 extent_mirror_num = mirror_num;
3302 if (is_dev_replace)
3303 scrub_remap_extent(fs_info, extent_logical,
3304 extent_len, &extent_physical,
3305 &extent_dev,
3306 &extent_mirror_num);
3307
3308 ret = btrfs_lookup_csums_range(csum_root,
3309 extent_logical,
3310 extent_logical +
3311 extent_len - 1,
3312 &sctx->csum_list, 1);
3313 if (ret)
3314 goto out;
3315
3316 ret = scrub_extent(sctx, map, extent_logical, extent_len,
3317 extent_physical, extent_dev, flags,
3318 generation, extent_mirror_num,
3319 extent_logical - logical + physical);
3320
3321 scrub_free_csums(sctx);
3322
3323 if (ret)
3324 goto out;
3325
3326 if (extent_logical + extent_len <
3327 key.objectid + bytes) {
3328 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
3329 /*
3330 * loop until we find next data stripe
3331 * or we have finished all stripes.
3332 */
3333 loop:
3334 physical += map->stripe_len;
3335 ret = get_raid56_logic_offset(physical,
3336 num, map, &logical,
3337 &stripe_logical);
3338 logical += base;
3339
3340 if (ret && physical < physical_end) {
3341 stripe_logical += base;
3342 stripe_end = stripe_logical +
3343 increment;
3344 ret = scrub_raid56_parity(sctx,
3345 map, scrub_dev, ppath,
3346 stripe_logical,
3347 stripe_end);
3348 if (ret)
3349 goto out;
3350 goto loop;
3351 }
3352 } else {
3353 physical += map->stripe_len;
3354 logical += increment;
3355 }
3356 if (logical < key.objectid + bytes) {
3357 cond_resched();
3358 goto again;
3359 }
3360
3361 if (physical >= physical_end) {
3362 stop_loop = 1;
3363 break;
3364 }
3365 }
3366 next:
3367 path->slots[0]++;
3368 }
3369 btrfs_release_path(path);
3370 skip:
3371 logical += increment;
3372 physical += map->stripe_len;
3373 spin_lock(&sctx->stat_lock);
3374 if (stop_loop)
3375 sctx->stat.last_physical = map->stripes[num].physical +
3376 length;
3377 else
3378 sctx->stat.last_physical = physical;
3379 spin_unlock(&sctx->stat_lock);
3380 if (stop_loop)
3381 break;
3382 }
3383 out:
3384 /* push queued extents */
3385 scrub_submit(sctx);
3386 mutex_lock(&sctx->wr_lock);
3387 scrub_wr_submit(sctx);
3388 mutex_unlock(&sctx->wr_lock);
3389
3390 blk_finish_plug(&plug);
3391 btrfs_free_path(path);
3392 btrfs_free_path(ppath);
3393 return ret < 0 ? ret : 0;
3394 }
3395
3396 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
3397 struct btrfs_device *scrub_dev,
3398 u64 chunk_offset, u64 length,
3399 u64 dev_offset,
3400 struct btrfs_block_group_cache *cache,
3401 int is_dev_replace)
3402 {
3403 struct btrfs_fs_info *fs_info = sctx->fs_info;
3404 struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
3405 struct map_lookup *map;
3406 struct extent_map *em;
3407 int i;
3408 int ret = 0;
3409
3410 read_lock(&map_tree->map_tree.lock);
3411 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
3412 read_unlock(&map_tree->map_tree.lock);
3413
3414 if (!em) {
3415 /*
3416 * Might have been an unused block group deleted by the cleaner
3417 * kthread or relocation.
3418 */
3419 spin_lock(&cache->lock);
3420 if (!cache->removed)
3421 ret = -EINVAL;
3422 spin_unlock(&cache->lock);
3423
3424 return ret;
3425 }
3426
3427 map = em->map_lookup;
3428 if (em->start != chunk_offset)
3429 goto out;
3430
3431 if (em->len < length)
3432 goto out;
3433
3434 for (i = 0; i < map->num_stripes; ++i) {
3435 if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
3436 map->stripes[i].physical == dev_offset) {
3437 ret = scrub_stripe(sctx, map, scrub_dev, i,
3438 chunk_offset, length,
3439 is_dev_replace);
3440 if (ret)
3441 goto out;
3442 }
3443 }
3444 out:
3445 free_extent_map(em);
3446
3447 return ret;
3448 }
3449
3450 static noinline_for_stack
3451 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
3452 struct btrfs_device *scrub_dev, u64 start, u64 end,
3453 int is_dev_replace)
3454 {
3455 struct btrfs_dev_extent *dev_extent = NULL;
3456 struct btrfs_path *path;
3457 struct btrfs_fs_info *fs_info = sctx->fs_info;
3458 struct btrfs_root *root = fs_info->dev_root;
3459 u64 length;
3460 u64 chunk_offset;
3461 int ret = 0;
3462 int ro_set;
3463 int slot;
3464 struct extent_buffer *l;
3465 struct btrfs_key key;
3466 struct btrfs_key found_key;
3467 struct btrfs_block_group_cache *cache;
3468 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
3469
3470 path = btrfs_alloc_path();
3471 if (!path)
3472 return -ENOMEM;
3473
3474 path->reada = READA_FORWARD;
3475 path->search_commit_root = 1;
3476 path->skip_locking = 1;
3477
3478 key.objectid = scrub_dev->devid;
3479 key.offset = 0ull;
3480 key.type = BTRFS_DEV_EXTENT_KEY;
3481
3482 while (1) {
3483 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3484 if (ret < 0)
3485 break;
3486 if (ret > 0) {
3487 if (path->slots[0] >=
3488 btrfs_header_nritems(path->nodes[0])) {
3489 ret = btrfs_next_leaf(root, path);
3490 if (ret < 0)
3491 break;
3492 if (ret > 0) {
3493 ret = 0;
3494 break;
3495 }
3496 } else {
3497 ret = 0;
3498 }
3499 }
3500
3501 l = path->nodes[0];
3502 slot = path->slots[0];
3503
3504 btrfs_item_key_to_cpu(l, &found_key, slot);
3505
3506 if (found_key.objectid != scrub_dev->devid)
3507 break;
3508
3509 if (found_key.type != BTRFS_DEV_EXTENT_KEY)
3510 break;
3511
3512 if (found_key.offset >= end)
3513 break;
3514
3515 if (found_key.offset < key.offset)
3516 break;
3517
3518 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
3519 length = btrfs_dev_extent_length(l, dev_extent);
3520
3521 if (found_key.offset + length <= start)
3522 goto skip;
3523
3524 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
3525
3526 /*
3527 * get a reference on the corresponding block group to prevent
3528 * the chunk from going away while we scrub it
3529 */
3530 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
3531
3532 /* some chunks are removed but not committed to disk yet,
3533 * continue scrubbing */
3534 if (!cache)
3535 goto skip;
3536
3537 /*
3538 * we need call btrfs_inc_block_group_ro() with scrubs_paused,
3539 * to avoid deadlock caused by:
3540 * btrfs_inc_block_group_ro()
3541 * -> btrfs_wait_for_commit()
3542 * -> btrfs_commit_transaction()
3543 * -> btrfs_scrub_pause()
3544 */
3545 scrub_pause_on(fs_info);
3546 ret = btrfs_inc_block_group_ro(cache);
3547 if (!ret && is_dev_replace) {
3548 /*
3549 * If we are doing a device replace wait for any tasks
3550 * that started dellaloc right before we set the block
3551 * group to RO mode, as they might have just allocated
3552 * an extent from it or decided they could do a nocow
3553 * write. And if any such tasks did that, wait for their
3554 * ordered extents to complete and then commit the
3555 * current transaction, so that we can later see the new
3556 * extent items in the extent tree - the ordered extents
3557 * create delayed data references (for cow writes) when
3558 * they complete, which will be run and insert the
3559 * corresponding extent items into the extent tree when
3560 * we commit the transaction they used when running
3561 * inode.c:btrfs_finish_ordered_io(). We later use
3562 * the commit root of the extent tree to find extents
3563 * to copy from the srcdev into the tgtdev, and we don't
3564 * want to miss any new extents.
3565 */
3566 btrfs_wait_block_group_reservations(cache);
3567 btrfs_wait_nocow_writers(cache);
3568 ret = btrfs_wait_ordered_roots(fs_info, U64_MAX,
3569 cache->key.objectid,
3570 cache->key.offset);
3571 if (ret > 0) {
3572 struct btrfs_trans_handle *trans;
3573
3574 trans = btrfs_join_transaction(root);
3575 if (IS_ERR(trans))
3576 ret = PTR_ERR(trans);
3577 else
3578 ret = btrfs_commit_transaction(trans);
3579 if (ret) {
3580 scrub_pause_off(fs_info);
3581 btrfs_put_block_group(cache);
3582 break;
3583 }
3584 }
3585 }
3586 scrub_pause_off(fs_info);
3587
3588 if (ret == 0) {
3589 ro_set = 1;
3590 } else if (ret == -ENOSPC) {
3591 /*
3592 * btrfs_inc_block_group_ro return -ENOSPC when it
3593 * failed in creating new chunk for metadata.
3594 * It is not a problem for scrub/replace, because
3595 * metadata are always cowed, and our scrub paused
3596 * commit_transactions.
3597 */
3598 ro_set = 0;
3599 } else {
3600 btrfs_warn(fs_info,
3601 "failed setting block group ro: %d", ret);
3602 btrfs_put_block_group(cache);
3603 break;
3604 }
3605
3606 btrfs_dev_replace_write_lock(&fs_info->dev_replace);
3607 dev_replace->cursor_right = found_key.offset + length;
3608 dev_replace->cursor_left = found_key.offset;
3609 dev_replace->item_needs_writeback = 1;
3610 btrfs_dev_replace_write_unlock(&fs_info->dev_replace);
3611 ret = scrub_chunk(sctx, scrub_dev, chunk_offset, length,
3612 found_key.offset, cache, is_dev_replace);
3613
3614 /*
3615 * flush, submit all pending read and write bios, afterwards
3616 * wait for them.
3617 * Note that in the dev replace case, a read request causes
3618 * write requests that are submitted in the read completion
3619 * worker. Therefore in the current situation, it is required
3620 * that all write requests are flushed, so that all read and
3621 * write requests are really completed when bios_in_flight
3622 * changes to 0.
3623 */
3624 sctx->flush_all_writes = true;
3625 scrub_submit(sctx);
3626 mutex_lock(&sctx->wr_lock);
3627 scrub_wr_submit(sctx);
3628 mutex_unlock(&sctx->wr_lock);
3629
3630 wait_event(sctx->list_wait,
3631 atomic_read(&sctx->bios_in_flight) == 0);
3632
3633 scrub_pause_on(fs_info);
3634
3635 /*
3636 * must be called before we decrease @scrub_paused.
3637 * make sure we don't block transaction commit while
3638 * we are waiting pending workers finished.
3639 */
3640 wait_event(sctx->list_wait,
3641 atomic_read(&sctx->workers_pending) == 0);
3642 sctx->flush_all_writes = false;
3643
3644 scrub_pause_off(fs_info);
3645
3646 btrfs_dev_replace_write_lock(&fs_info->dev_replace);
3647 dev_replace->cursor_left = dev_replace->cursor_right;
3648 dev_replace->item_needs_writeback = 1;
3649 btrfs_dev_replace_write_unlock(&fs_info->dev_replace);
3650
3651 if (ro_set)
3652 btrfs_dec_block_group_ro(cache);
3653
3654 /*
3655 * We might have prevented the cleaner kthread from deleting
3656 * this block group if it was already unused because we raced
3657 * and set it to RO mode first. So add it back to the unused
3658 * list, otherwise it might not ever be deleted unless a manual
3659 * balance is triggered or it becomes used and unused again.
3660 */
3661 spin_lock(&cache->lock);
3662 if (!cache->removed && !cache->ro && cache->reserved == 0 &&
3663 btrfs_block_group_used(&cache->item) == 0) {
3664 spin_unlock(&cache->lock);
3665 btrfs_mark_bg_unused(cache);
3666 } else {
3667 spin_unlock(&cache->lock);
3668 }
3669
3670 btrfs_put_block_group(cache);
3671 if (ret)
3672 break;
3673 if (is_dev_replace &&
3674 atomic64_read(&dev_replace->num_write_errors) > 0) {
3675 ret = -EIO;
3676 break;
3677 }
3678 if (sctx->stat.malloc_errors > 0) {
3679 ret = -ENOMEM;
3680 break;
3681 }
3682 skip:
3683 key.offset = found_key.offset + length;
3684 btrfs_release_path(path);
3685 }
3686
3687 btrfs_free_path(path);
3688
3689 return ret;
3690 }
3691
3692 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
3693 struct btrfs_device *scrub_dev)
3694 {
3695 int i;
3696 u64 bytenr;
3697 u64 gen;
3698 int ret;
3699 struct btrfs_fs_info *fs_info = sctx->fs_info;
3700
3701 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
3702 return -EIO;
3703
3704 /* Seed devices of a new filesystem has their own generation. */
3705 if (scrub_dev->fs_devices != fs_info->fs_devices)
3706 gen = scrub_dev->generation;
3707 else
3708 gen = fs_info->last_trans_committed;
3709
3710 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
3711 bytenr = btrfs_sb_offset(i);
3712 if (bytenr + BTRFS_SUPER_INFO_SIZE >
3713 scrub_dev->commit_total_bytes)
3714 break;
3715
3716 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
3717 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
3718 NULL, 1, bytenr);
3719 if (ret)
3720 return ret;
3721 }
3722 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3723
3724 return 0;
3725 }
3726
3727 /*
3728 * get a reference count on fs_info->scrub_workers. start worker if necessary
3729 */
3730 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
3731 int is_dev_replace)
3732 {
3733 unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND;
3734 int max_active = fs_info->thread_pool_size;
3735
3736 if (fs_info->scrub_workers_refcnt == 0) {
3737 fs_info->scrub_workers = btrfs_alloc_workqueue(fs_info, "scrub",
3738 flags, is_dev_replace ? 1 : max_active, 4);
3739 if (!fs_info->scrub_workers)
3740 goto fail_scrub_workers;
3741
3742 fs_info->scrub_wr_completion_workers =
3743 btrfs_alloc_workqueue(fs_info, "scrubwrc", flags,
3744 max_active, 2);
3745 if (!fs_info->scrub_wr_completion_workers)
3746 goto fail_scrub_wr_completion_workers;
3747
3748 fs_info->scrub_parity_workers =
3749 btrfs_alloc_workqueue(fs_info, "scrubparity", flags,
3750 max_active, 2);
3751 if (!fs_info->scrub_parity_workers)
3752 goto fail_scrub_parity_workers;
3753 }
3754 ++fs_info->scrub_workers_refcnt;
3755 return 0;
3756
3757 fail_scrub_parity_workers:
3758 btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers);
3759 fail_scrub_wr_completion_workers:
3760 btrfs_destroy_workqueue(fs_info->scrub_workers);
3761 fail_scrub_workers:
3762 return -ENOMEM;
3763 }
3764
3765 static noinline_for_stack void scrub_workers_put(struct btrfs_fs_info *fs_info)
3766 {
3767 if (--fs_info->scrub_workers_refcnt == 0) {
3768 btrfs_destroy_workqueue(fs_info->scrub_workers);
3769 btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers);
3770 btrfs_destroy_workqueue(fs_info->scrub_parity_workers);
3771 }
3772 WARN_ON(fs_info->scrub_workers_refcnt < 0);
3773 }
3774
3775 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
3776 u64 end, struct btrfs_scrub_progress *progress,
3777 int readonly, int is_dev_replace)
3778 {
3779 struct scrub_ctx *sctx;
3780 int ret;
3781 struct btrfs_device *dev;
3782
3783 if (btrfs_fs_closing(fs_info))
3784 return -EINVAL;
3785
3786 if (fs_info->nodesize > BTRFS_STRIPE_LEN) {
3787 /*
3788 * in this case scrub is unable to calculate the checksum
3789 * the way scrub is implemented. Do not handle this
3790 * situation at all because it won't ever happen.
3791 */
3792 btrfs_err(fs_info,
3793 "scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails",
3794 fs_info->nodesize,
3795 BTRFS_STRIPE_LEN);
3796 return -EINVAL;
3797 }
3798
3799 if (fs_info->sectorsize != PAGE_SIZE) {
3800 /* not supported for data w/o checksums */
3801 btrfs_err_rl(fs_info,
3802 "scrub: size assumption sectorsize != PAGE_SIZE (%d != %lu) fails",
3803 fs_info->sectorsize, PAGE_SIZE);
3804 return -EINVAL;
3805 }
3806
3807 if (fs_info->nodesize >
3808 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK ||
3809 fs_info->sectorsize > PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) {
3810 /*
3811 * would exhaust the array bounds of pagev member in
3812 * struct scrub_block
3813 */
3814 btrfs_err(fs_info,
3815 "scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails",
3816 fs_info->nodesize,
3817 SCRUB_MAX_PAGES_PER_BLOCK,
3818 fs_info->sectorsize,
3819 SCRUB_MAX_PAGES_PER_BLOCK);
3820 return -EINVAL;
3821 }
3822
3823
3824 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3825 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
3826 if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) &&
3827 !is_dev_replace)) {
3828 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3829 return -ENODEV;
3830 }
3831
3832 if (!is_dev_replace && !readonly &&
3833 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) {
3834 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3835 btrfs_err_in_rcu(fs_info, "scrub: device %s is not writable",
3836 rcu_str_deref(dev->name));
3837 return -EROFS;
3838 }
3839
3840 mutex_lock(&fs_info->scrub_lock);
3841 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) ||
3842 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) {
3843 mutex_unlock(&fs_info->scrub_lock);
3844 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3845 return -EIO;
3846 }
3847
3848 btrfs_dev_replace_read_lock(&fs_info->dev_replace);
3849 if (dev->scrub_ctx ||
3850 (!is_dev_replace &&
3851 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
3852 btrfs_dev_replace_read_unlock(&fs_info->dev_replace);
3853 mutex_unlock(&fs_info->scrub_lock);
3854 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3855 return -EINPROGRESS;
3856 }
3857 btrfs_dev_replace_read_unlock(&fs_info->dev_replace);
3858
3859 ret = scrub_workers_get(fs_info, is_dev_replace);
3860 if (ret) {
3861 mutex_unlock(&fs_info->scrub_lock);
3862 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3863 return ret;
3864 }
3865
3866 sctx = scrub_setup_ctx(dev, is_dev_replace);
3867 if (IS_ERR(sctx)) {
3868 mutex_unlock(&fs_info->scrub_lock);
3869 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3870 scrub_workers_put(fs_info);
3871 return PTR_ERR(sctx);
3872 }
3873 sctx->readonly = readonly;
3874 dev->scrub_ctx = sctx;
3875 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3876
3877 /*
3878 * checking @scrub_pause_req here, we can avoid
3879 * race between committing transaction and scrubbing.
3880 */
3881 __scrub_blocked_if_needed(fs_info);
3882 atomic_inc(&fs_info->scrubs_running);
3883 mutex_unlock(&fs_info->scrub_lock);
3884
3885 if (!is_dev_replace) {
3886 /*
3887 * by holding device list mutex, we can
3888 * kick off writing super in log tree sync.
3889 */
3890 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3891 ret = scrub_supers(sctx, dev);
3892 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3893 }
3894
3895 if (!ret)
3896 ret = scrub_enumerate_chunks(sctx, dev, start, end,
3897 is_dev_replace);
3898
3899 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
3900 atomic_dec(&fs_info->scrubs_running);
3901 wake_up(&fs_info->scrub_pause_wait);
3902
3903 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0);
3904
3905 if (progress)
3906 memcpy(progress, &sctx->stat, sizeof(*progress));
3907
3908 mutex_lock(&fs_info->scrub_lock);
3909 dev->scrub_ctx = NULL;
3910 scrub_workers_put(fs_info);
3911 mutex_unlock(&fs_info->scrub_lock);
3912
3913 scrub_put_ctx(sctx);
3914
3915 return ret;
3916 }
3917
3918 void btrfs_scrub_pause(struct btrfs_fs_info *fs_info)
3919 {
3920 mutex_lock(&fs_info->scrub_lock);
3921 atomic_inc(&fs_info->scrub_pause_req);
3922 while (atomic_read(&fs_info->scrubs_paused) !=
3923 atomic_read(&fs_info->scrubs_running)) {
3924 mutex_unlock(&fs_info->scrub_lock);
3925 wait_event(fs_info->scrub_pause_wait,
3926 atomic_read(&fs_info->scrubs_paused) ==
3927 atomic_read(&fs_info->scrubs_running));
3928 mutex_lock(&fs_info->scrub_lock);
3929 }
3930 mutex_unlock(&fs_info->scrub_lock);
3931 }
3932
3933 void btrfs_scrub_continue(struct btrfs_fs_info *fs_info)
3934 {
3935 atomic_dec(&fs_info->scrub_pause_req);
3936 wake_up(&fs_info->scrub_pause_wait);
3937 }
3938
3939 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
3940 {
3941 mutex_lock(&fs_info->scrub_lock);
3942 if (!atomic_read(&fs_info->scrubs_running)) {
3943 mutex_unlock(&fs_info->scrub_lock);
3944 return -ENOTCONN;
3945 }
3946
3947 atomic_inc(&fs_info->scrub_cancel_req);
3948 while (atomic_read(&fs_info->scrubs_running)) {
3949 mutex_unlock(&fs_info->scrub_lock);
3950 wait_event(fs_info->scrub_pause_wait,
3951 atomic_read(&fs_info->scrubs_running) == 0);
3952 mutex_lock(&fs_info->scrub_lock);
3953 }
3954 atomic_dec(&fs_info->scrub_cancel_req);
3955 mutex_unlock(&fs_info->scrub_lock);
3956
3957 return 0;
3958 }
3959
3960 int btrfs_scrub_cancel_dev(struct btrfs_fs_info *fs_info,
3961 struct btrfs_device *dev)
3962 {
3963 struct scrub_ctx *sctx;
3964
3965 mutex_lock(&fs_info->scrub_lock);
3966 sctx = dev->scrub_ctx;
3967 if (!sctx) {
3968 mutex_unlock(&fs_info->scrub_lock);
3969 return -ENOTCONN;
3970 }
3971 atomic_inc(&sctx->cancel_req);
3972 while (dev->scrub_ctx) {
3973 mutex_unlock(&fs_info->scrub_lock);
3974 wait_event(fs_info->scrub_pause_wait,
3975 dev->scrub_ctx == NULL);
3976 mutex_lock(&fs_info->scrub_lock);
3977 }
3978 mutex_unlock(&fs_info->scrub_lock);
3979
3980 return 0;
3981 }
3982
3983 int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid,
3984 struct btrfs_scrub_progress *progress)
3985 {
3986 struct btrfs_device *dev;
3987 struct scrub_ctx *sctx = NULL;
3988
3989 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3990 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
3991 if (dev)
3992 sctx = dev->scrub_ctx;
3993 if (sctx)
3994 memcpy(progress, &sctx->stat, sizeof(*progress));
3995 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3996
3997 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
3998 }
3999
4000 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
4001 u64 extent_logical, u64 extent_len,
4002 u64 *extent_physical,
4003 struct btrfs_device **extent_dev,
4004 int *extent_mirror_num)
4005 {
4006 u64 mapped_length;
4007 struct btrfs_bio *bbio = NULL;
4008 int ret;
4009
4010 mapped_length = extent_len;
4011 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, extent_logical,
4012 &mapped_length, &bbio, 0);
4013 if (ret || !bbio || mapped_length < extent_len ||
4014 !bbio->stripes[0].dev->bdev) {
4015 btrfs_put_bbio(bbio);
4016 return;
4017 }
4018
4019 *extent_physical = bbio->stripes[0].physical;
4020 *extent_mirror_num = bbio->mirror_num;
4021 *extent_dev = bbio->stripes[0].dev;
4022 btrfs_put_bbio(bbio);
4023 }
(deprecated) Btrfs devel tree