2 * Copyright (C) 2011, 2012 STRATO. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/blkdev.h>
20 #include <linux/ratelimit.h>
24 #include "ordered-data.h"
25 #include "transaction.h"
27 #include "extent_io.h"
28 #include "dev-replace.h"
29 #include "check-integrity.h"
30 #include "rcu-string.h"
34 * This is only the first step towards a full-features scrub. It reads all
35 * extent and super block and verifies the checksums. In case a bad checksum
36 * is found or the extent cannot be read, good data will be written back if
39 * Future enhancements:
40 * - In case an unrepairable extent is encountered, track which files are
41 * affected and report them
42 * - track and record media errors, throw out bad devices
43 * - add a mode to also read unallocated space
50 * the following three values only influence the performance.
51 * The last one configures the number of parallel and outstanding I/O
52 * operations. The first two values configure an upper limit for the number
53 * of (dynamically allocated) pages that are added to a bio.
55 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */
56 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */
57 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */
60 * the following value times PAGE_SIZE needs to be large enough to match the
61 * largest node/leaf/sector size that shall be supported.
62 * Values larger than BTRFS_STRIPE_LEN are not supported.
64 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
67 struct scrub_block *sblock;
69 struct btrfs_device *dev;
70 u64 flags; /* extent flags */
74 u64 physical_for_dev_replace;
77 unsigned int mirror_num:8;
78 unsigned int have_csum:1;
79 unsigned int io_error:1;
81 u8 csum[BTRFS_CSUM_SIZE];
86 struct scrub_ctx *sctx;
87 struct btrfs_device *dev;
92 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO
93 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO];
95 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO];
99 struct btrfs_work work;
103 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK];
105 atomic_t outstanding_pages;
106 atomic_t ref_count; /* free mem on transition to zero */
107 struct scrub_ctx *sctx;
109 unsigned int header_error:1;
110 unsigned int checksum_error:1;
111 unsigned int no_io_error_seen:1;
112 unsigned int generation_error:1; /* also sets header_error */
116 struct scrub_wr_ctx {
117 struct scrub_bio *wr_curr_bio;
118 struct btrfs_device *tgtdev;
119 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
120 atomic_t flush_all_writes;
121 struct mutex wr_lock;
125 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX];
126 struct btrfs_root *dev_root;
129 atomic_t bios_in_flight;
130 atomic_t workers_pending;
131 spinlock_t list_lock;
132 wait_queue_head_t list_wait;
134 struct list_head csum_list;
137 int pages_per_rd_bio;
143 struct scrub_wr_ctx wr_ctx;
148 struct btrfs_scrub_progress stat;
149 spinlock_t stat_lock;
152 struct scrub_fixup_nodatasum {
153 struct scrub_ctx *sctx;
154 struct btrfs_device *dev;
156 struct btrfs_root *root;
157 struct btrfs_work work;
161 struct scrub_copy_nocow_ctx {
162 struct scrub_ctx *sctx;
166 u64 physical_for_dev_replace;
167 struct btrfs_work work;
170 struct scrub_warning {
171 struct btrfs_path *path;
172 u64 extent_item_size;
178 struct btrfs_device *dev;
184 static void scrub_pending_bio_inc(struct scrub_ctx *sctx);
185 static void scrub_pending_bio_dec(struct scrub_ctx *sctx);
186 static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx);
187 static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx);
188 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
189 static int scrub_setup_recheck_block(struct scrub_ctx *sctx,
190 struct btrfs_fs_info *fs_info,
191 struct scrub_block *original_sblock,
192 u64 length, u64 logical,
193 struct scrub_block *sblocks_for_recheck);
194 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
195 struct scrub_block *sblock, int is_metadata,
196 int have_csum, u8 *csum, u64 generation,
198 static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
199 struct scrub_block *sblock,
200 int is_metadata, int have_csum,
201 const u8 *csum, u64 generation,
203 static void scrub_complete_bio_end_io(struct bio *bio, int err);
204 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
205 struct scrub_block *sblock_good,
207 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
208 struct scrub_block *sblock_good,
209 int page_num, int force_write);
210 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock);
211 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
213 static int scrub_checksum_data(struct scrub_block *sblock);
214 static int scrub_checksum_tree_block(struct scrub_block *sblock);
215 static int scrub_checksum_super(struct scrub_block *sblock);
216 static void scrub_block_get(struct scrub_block *sblock);
217 static void scrub_block_put(struct scrub_block *sblock);
218 static void scrub_page_get(struct scrub_page *spage);
219 static void scrub_page_put(struct scrub_page *spage);
220 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
221 struct scrub_page *spage);
222 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
223 u64 physical, struct btrfs_device *dev, u64 flags,
224 u64 gen, int mirror_num, u8 *csum, int force,
225 u64 physical_for_dev_replace);
226 static void scrub_bio_end_io(struct bio *bio, int err);
227 static void scrub_bio_end_io_worker(struct btrfs_work *work);
228 static void scrub_block_complete(struct scrub_block *sblock);
229 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
230 u64 extent_logical, u64 extent_len,
231 u64 *extent_physical,
232 struct btrfs_device **extent_dev,
233 int *extent_mirror_num);
234 static int scrub_setup_wr_ctx(struct scrub_ctx *sctx,
235 struct scrub_wr_ctx *wr_ctx,
236 struct btrfs_fs_info *fs_info,
237 struct btrfs_device *dev,
239 static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx);
240 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
241 struct scrub_page *spage);
242 static void scrub_wr_submit(struct scrub_ctx *sctx);
243 static void scrub_wr_bio_end_io(struct bio *bio, int err);
244 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work);
245 static int write_page_nocow(struct scrub_ctx *sctx,
246 u64 physical_for_dev_replace, struct page *page);
247 static int copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root,
249 static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
250 int mirror_num, u64 physical_for_dev_replace);
251 static void copy_nocow_pages_worker(struct btrfs_work *work);
254 static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
256 atomic_inc(&sctx->bios_in_flight);
259 static void scrub_pending_bio_dec(struct scrub_ctx *sctx)
261 atomic_dec(&sctx->bios_in_flight);
262 wake_up(&sctx->list_wait);
266 * used for workers that require transaction commits (i.e., for the
269 static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx)
271 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
274 * increment scrubs_running to prevent cancel requests from
275 * completing as long as a worker is running. we must also
276 * increment scrubs_paused to prevent deadlocking on pause
277 * requests used for transactions commits (as the worker uses a
278 * transaction context). it is safe to regard the worker
279 * as paused for all matters practical. effectively, we only
280 * avoid cancellation requests from completing.
282 mutex_lock(&fs_info->scrub_lock);
283 atomic_inc(&fs_info->scrubs_running);
284 atomic_inc(&fs_info->scrubs_paused);
285 mutex_unlock(&fs_info->scrub_lock);
286 atomic_inc(&sctx->workers_pending);
289 /* used for workers that require transaction commits */
290 static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx)
292 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
295 * see scrub_pending_trans_workers_inc() why we're pretending
296 * to be paused in the scrub counters
298 mutex_lock(&fs_info->scrub_lock);
299 atomic_dec(&fs_info->scrubs_running);
300 atomic_dec(&fs_info->scrubs_paused);
301 mutex_unlock(&fs_info->scrub_lock);
302 atomic_dec(&sctx->workers_pending);
303 wake_up(&fs_info->scrub_pause_wait);
304 wake_up(&sctx->list_wait);
307 static void scrub_free_csums(struct scrub_ctx *sctx)
309 while (!list_empty(&sctx->csum_list)) {
310 struct btrfs_ordered_sum *sum;
311 sum = list_first_entry(&sctx->csum_list,
312 struct btrfs_ordered_sum, list);
313 list_del(&sum->list);
318 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
325 scrub_free_wr_ctx(&sctx->wr_ctx);
327 /* this can happen when scrub is cancelled */
328 if (sctx->curr != -1) {
329 struct scrub_bio *sbio = sctx->bios[sctx->curr];
331 for (i = 0; i < sbio->page_count; i++) {
332 WARN_ON(!sbio->pagev[i]->page);
333 scrub_block_put(sbio->pagev[i]->sblock);
338 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
339 struct scrub_bio *sbio = sctx->bios[i];
346 scrub_free_csums(sctx);
350 static noinline_for_stack
351 struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
353 struct scrub_ctx *sctx;
355 struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
356 int pages_per_rd_bio;
360 * the setting of pages_per_rd_bio is correct for scrub but might
361 * be wrong for the dev_replace code where we might read from
362 * different devices in the initial huge bios. However, that
363 * code is able to correctly handle the case when adding a page
367 pages_per_rd_bio = min_t(int, SCRUB_PAGES_PER_RD_BIO,
368 bio_get_nr_vecs(dev->bdev));
370 pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
371 sctx = kzalloc(sizeof(*sctx), GFP_NOFS);
374 sctx->is_dev_replace = is_dev_replace;
375 sctx->pages_per_rd_bio = pages_per_rd_bio;
377 sctx->dev_root = dev->dev_root;
378 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
379 struct scrub_bio *sbio;
381 sbio = kzalloc(sizeof(*sbio), GFP_NOFS);
384 sctx->bios[i] = sbio;
388 sbio->page_count = 0;
389 sbio->work.func = scrub_bio_end_io_worker;
391 if (i != SCRUB_BIOS_PER_SCTX - 1)
392 sctx->bios[i]->next_free = i + 1;
394 sctx->bios[i]->next_free = -1;
396 sctx->first_free = 0;
397 sctx->nodesize = dev->dev_root->nodesize;
398 sctx->leafsize = dev->dev_root->leafsize;
399 sctx->sectorsize = dev->dev_root->sectorsize;
400 atomic_set(&sctx->bios_in_flight, 0);
401 atomic_set(&sctx->workers_pending, 0);
402 atomic_set(&sctx->cancel_req, 0);
403 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
404 INIT_LIST_HEAD(&sctx->csum_list);
406 spin_lock_init(&sctx->list_lock);
407 spin_lock_init(&sctx->stat_lock);
408 init_waitqueue_head(&sctx->list_wait);
410 ret = scrub_setup_wr_ctx(sctx, &sctx->wr_ctx, fs_info,
411 fs_info->dev_replace.tgtdev, is_dev_replace);
413 scrub_free_ctx(sctx);
419 scrub_free_ctx(sctx);
420 return ERR_PTR(-ENOMEM);
423 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root,
430 struct extent_buffer *eb;
431 struct btrfs_inode_item *inode_item;
432 struct scrub_warning *swarn = warn_ctx;
433 struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info;
434 struct inode_fs_paths *ipath = NULL;
435 struct btrfs_root *local_root;
436 struct btrfs_key root_key;
438 root_key.objectid = root;
439 root_key.type = BTRFS_ROOT_ITEM_KEY;
440 root_key.offset = (u64)-1;
441 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
442 if (IS_ERR(local_root)) {
443 ret = PTR_ERR(local_root);
447 ret = inode_item_info(inum, 0, local_root, swarn->path);
449 btrfs_release_path(swarn->path);
453 eb = swarn->path->nodes[0];
454 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
455 struct btrfs_inode_item);
456 isize = btrfs_inode_size(eb, inode_item);
457 nlink = btrfs_inode_nlink(eb, inode_item);
458 btrfs_release_path(swarn->path);
460 ipath = init_ipath(4096, local_root, swarn->path);
462 ret = PTR_ERR(ipath);
466 ret = paths_from_inode(inum, ipath);
472 * we deliberately ignore the bit ipath might have been too small to
473 * hold all of the paths here
475 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
476 printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
477 "%s, sector %llu, root %llu, inode %llu, offset %llu, "
478 "length %llu, links %u (path: %s)\n", swarn->errstr,
479 swarn->logical, rcu_str_deref(swarn->dev->name),
480 (unsigned long long)swarn->sector, root, inum, offset,
481 min(isize - offset, (u64)PAGE_SIZE), nlink,
482 (char *)(unsigned long)ipath->fspath->val[i]);
488 printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
489 "%s, sector %llu, root %llu, inode %llu, offset %llu: path "
490 "resolving failed with ret=%d\n", swarn->errstr,
491 swarn->logical, rcu_str_deref(swarn->dev->name),
492 (unsigned long long)swarn->sector, root, inum, offset, ret);
498 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
500 struct btrfs_device *dev;
501 struct btrfs_fs_info *fs_info;
502 struct btrfs_path *path;
503 struct btrfs_key found_key;
504 struct extent_buffer *eb;
505 struct btrfs_extent_item *ei;
506 struct scrub_warning swarn;
507 unsigned long ptr = 0;
513 const int bufsize = 4096;
516 WARN_ON(sblock->page_count < 1);
517 dev = sblock->pagev[0]->dev;
518 fs_info = sblock->sctx->dev_root->fs_info;
520 path = btrfs_alloc_path();
522 swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS);
523 swarn.msg_buf = kmalloc(bufsize, GFP_NOFS);
524 swarn.sector = (sblock->pagev[0]->physical) >> 9;
525 swarn.logical = sblock->pagev[0]->logical;
526 swarn.errstr = errstr;
528 swarn.msg_bufsize = bufsize;
529 swarn.scratch_bufsize = bufsize;
531 if (!path || !swarn.scratch_buf || !swarn.msg_buf)
534 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
539 extent_item_pos = swarn.logical - found_key.objectid;
540 swarn.extent_item_size = found_key.offset;
543 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
544 item_size = btrfs_item_size_nr(eb, path->slots[0]);
545 btrfs_release_path(path);
547 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
549 ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
550 &ref_root, &ref_level);
551 printk_in_rcu(KERN_WARNING
552 "btrfs: %s at logical %llu on dev %s, "
553 "sector %llu: metadata %s (level %d) in tree "
554 "%llu\n", errstr, swarn.logical,
555 rcu_str_deref(dev->name),
556 (unsigned long long)swarn.sector,
557 ref_level ? "node" : "leaf",
558 ret < 0 ? -1 : ref_level,
559 ret < 0 ? -1 : ref_root);
564 iterate_extent_inodes(fs_info, found_key.objectid,
566 scrub_print_warning_inode, &swarn);
570 btrfs_free_path(path);
571 kfree(swarn.scratch_buf);
572 kfree(swarn.msg_buf);
575 static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *fixup_ctx)
577 struct page *page = NULL;
579 struct scrub_fixup_nodatasum *fixup = fixup_ctx;
582 struct btrfs_key key;
583 struct inode *inode = NULL;
584 struct btrfs_fs_info *fs_info;
585 u64 end = offset + PAGE_SIZE - 1;
586 struct btrfs_root *local_root;
590 key.type = BTRFS_ROOT_ITEM_KEY;
591 key.offset = (u64)-1;
593 fs_info = fixup->root->fs_info;
594 srcu_index = srcu_read_lock(&fs_info->subvol_srcu);
596 local_root = btrfs_read_fs_root_no_name(fs_info, &key);
597 if (IS_ERR(local_root)) {
598 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
599 return PTR_ERR(local_root);
602 key.type = BTRFS_INODE_ITEM_KEY;
605 inode = btrfs_iget(fs_info->sb, &key, local_root, NULL);
606 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
608 return PTR_ERR(inode);
610 index = offset >> PAGE_CACHE_SHIFT;
612 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
618 if (PageUptodate(page)) {
619 if (PageDirty(page)) {
621 * we need to write the data to the defect sector. the
622 * data that was in that sector is not in memory,
623 * because the page was modified. we must not write the
624 * modified page to that sector.
626 * TODO: what could be done here: wait for the delalloc
627 * runner to write out that page (might involve
628 * COW) and see whether the sector is still
629 * referenced afterwards.
631 * For the meantime, we'll treat this error
632 * incorrectable, although there is a chance that a
633 * later scrub will find the bad sector again and that
634 * there's no dirty page in memory, then.
639 fs_info = BTRFS_I(inode)->root->fs_info;
640 ret = repair_io_failure(fs_info, offset, PAGE_SIZE,
641 fixup->logical, page,
647 * we need to get good data first. the general readpage path
648 * will call repair_io_failure for us, we just have to make
649 * sure we read the bad mirror.
651 ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
652 EXTENT_DAMAGED, GFP_NOFS);
654 /* set_extent_bits should give proper error */
661 ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
664 wait_on_page_locked(page);
666 corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset,
667 end, EXTENT_DAMAGED, 0, NULL);
669 clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
670 EXTENT_DAMAGED, GFP_NOFS);
682 if (ret == 0 && corrected) {
684 * we only need to call readpage for one of the inodes belonging
685 * to this extent. so make iterate_extent_inodes stop
693 static void scrub_fixup_nodatasum(struct btrfs_work *work)
696 struct scrub_fixup_nodatasum *fixup;
697 struct scrub_ctx *sctx;
698 struct btrfs_trans_handle *trans = NULL;
699 struct btrfs_fs_info *fs_info;
700 struct btrfs_path *path;
701 int uncorrectable = 0;
703 fixup = container_of(work, struct scrub_fixup_nodatasum, work);
705 fs_info = fixup->root->fs_info;
707 path = btrfs_alloc_path();
709 spin_lock(&sctx->stat_lock);
710 ++sctx->stat.malloc_errors;
711 spin_unlock(&sctx->stat_lock);
716 trans = btrfs_join_transaction(fixup->root);
723 * the idea is to trigger a regular read through the standard path. we
724 * read a page from the (failed) logical address by specifying the
725 * corresponding copynum of the failed sector. thus, that readpage is
727 * that is the point where on-the-fly error correction will kick in
728 * (once it's finished) and rewrite the failed sector if a good copy
731 ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info,
732 path, scrub_fixup_readpage,
740 spin_lock(&sctx->stat_lock);
741 ++sctx->stat.corrected_errors;
742 spin_unlock(&sctx->stat_lock);
745 if (trans && !IS_ERR(trans))
746 btrfs_end_transaction(trans, fixup->root);
748 spin_lock(&sctx->stat_lock);
749 ++sctx->stat.uncorrectable_errors;
750 spin_unlock(&sctx->stat_lock);
751 btrfs_dev_replace_stats_inc(
752 &sctx->dev_root->fs_info->dev_replace.
753 num_uncorrectable_read_errors);
754 printk_ratelimited_in_rcu(KERN_ERR
755 "btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
756 (unsigned long long)fixup->logical,
757 rcu_str_deref(fixup->dev->name));
760 btrfs_free_path(path);
763 scrub_pending_trans_workers_dec(sctx);
767 * scrub_handle_errored_block gets called when either verification of the
768 * pages failed or the bio failed to read, e.g. with EIO. In the latter
769 * case, this function handles all pages in the bio, even though only one
771 * The goal of this function is to repair the errored block by using the
772 * contents of one of the mirrors.
774 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
776 struct scrub_ctx *sctx = sblock_to_check->sctx;
777 struct btrfs_device *dev;
778 struct btrfs_fs_info *fs_info;
782 unsigned int failed_mirror_index;
783 unsigned int is_metadata;
784 unsigned int have_csum;
786 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
787 struct scrub_block *sblock_bad;
792 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
793 DEFAULT_RATELIMIT_BURST);
795 BUG_ON(sblock_to_check->page_count < 1);
796 fs_info = sctx->dev_root->fs_info;
797 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) {
799 * if we find an error in a super block, we just report it.
800 * They will get written with the next transaction commit
803 spin_lock(&sctx->stat_lock);
804 ++sctx->stat.super_errors;
805 spin_unlock(&sctx->stat_lock);
808 length = sblock_to_check->page_count * PAGE_SIZE;
809 logical = sblock_to_check->pagev[0]->logical;
810 generation = sblock_to_check->pagev[0]->generation;
811 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1);
812 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1;
813 is_metadata = !(sblock_to_check->pagev[0]->flags &
814 BTRFS_EXTENT_FLAG_DATA);
815 have_csum = sblock_to_check->pagev[0]->have_csum;
816 csum = sblock_to_check->pagev[0]->csum;
817 dev = sblock_to_check->pagev[0]->dev;
819 if (sctx->is_dev_replace && !is_metadata && !have_csum) {
820 sblocks_for_recheck = NULL;
825 * read all mirrors one after the other. This includes to
826 * re-read the extent or metadata block that failed (that was
827 * the cause that this fixup code is called) another time,
828 * page by page this time in order to know which pages
829 * caused I/O errors and which ones are good (for all mirrors).
830 * It is the goal to handle the situation when more than one
831 * mirror contains I/O errors, but the errors do not
832 * overlap, i.e. the data can be repaired by selecting the
833 * pages from those mirrors without I/O error on the
834 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
835 * would be that mirror #1 has an I/O error on the first page,
836 * the second page is good, and mirror #2 has an I/O error on
837 * the second page, but the first page is good.
838 * Then the first page of the first mirror can be repaired by
839 * taking the first page of the second mirror, and the
840 * second page of the second mirror can be repaired by
841 * copying the contents of the 2nd page of the 1st mirror.
842 * One more note: if the pages of one mirror contain I/O
843 * errors, the checksum cannot be verified. In order to get
844 * the best data for repairing, the first attempt is to find
845 * a mirror without I/O errors and with a validated checksum.
846 * Only if this is not possible, the pages are picked from
847 * mirrors with I/O errors without considering the checksum.
848 * If the latter is the case, at the end, the checksum of the
849 * repaired area is verified in order to correctly maintain
853 sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS *
854 sizeof(*sblocks_for_recheck),
856 if (!sblocks_for_recheck) {
857 spin_lock(&sctx->stat_lock);
858 sctx->stat.malloc_errors++;
859 sctx->stat.read_errors++;
860 sctx->stat.uncorrectable_errors++;
861 spin_unlock(&sctx->stat_lock);
862 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
866 /* setup the context, map the logical blocks and alloc the pages */
867 ret = scrub_setup_recheck_block(sctx, fs_info, sblock_to_check, length,
868 logical, sblocks_for_recheck);
870 spin_lock(&sctx->stat_lock);
871 sctx->stat.read_errors++;
872 sctx->stat.uncorrectable_errors++;
873 spin_unlock(&sctx->stat_lock);
874 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
877 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
878 sblock_bad = sblocks_for_recheck + failed_mirror_index;
880 /* build and submit the bios for the failed mirror, check checksums */
881 scrub_recheck_block(fs_info, sblock_bad, is_metadata, have_csum,
882 csum, generation, sctx->csum_size);
884 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
885 sblock_bad->no_io_error_seen) {
887 * the error disappeared after reading page by page, or
888 * the area was part of a huge bio and other parts of the
889 * bio caused I/O errors, or the block layer merged several
890 * read requests into one and the error is caused by a
891 * different bio (usually one of the two latter cases is
894 spin_lock(&sctx->stat_lock);
895 sctx->stat.unverified_errors++;
896 spin_unlock(&sctx->stat_lock);
898 if (sctx->is_dev_replace)
899 scrub_write_block_to_dev_replace(sblock_bad);
903 if (!sblock_bad->no_io_error_seen) {
904 spin_lock(&sctx->stat_lock);
905 sctx->stat.read_errors++;
906 spin_unlock(&sctx->stat_lock);
907 if (__ratelimit(&_rs))
908 scrub_print_warning("i/o error", sblock_to_check);
909 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
910 } else if (sblock_bad->checksum_error) {
911 spin_lock(&sctx->stat_lock);
912 sctx->stat.csum_errors++;
913 spin_unlock(&sctx->stat_lock);
914 if (__ratelimit(&_rs))
915 scrub_print_warning("checksum error", sblock_to_check);
916 btrfs_dev_stat_inc_and_print(dev,
917 BTRFS_DEV_STAT_CORRUPTION_ERRS);
918 } else if (sblock_bad->header_error) {
919 spin_lock(&sctx->stat_lock);
920 sctx->stat.verify_errors++;
921 spin_unlock(&sctx->stat_lock);
922 if (__ratelimit(&_rs))
923 scrub_print_warning("checksum/header error",
925 if (sblock_bad->generation_error)
926 btrfs_dev_stat_inc_and_print(dev,
927 BTRFS_DEV_STAT_GENERATION_ERRS);
929 btrfs_dev_stat_inc_and_print(dev,
930 BTRFS_DEV_STAT_CORRUPTION_ERRS);
933 if (sctx->readonly && !sctx->is_dev_replace)
934 goto did_not_correct_error;
936 if (!is_metadata && !have_csum) {
937 struct scrub_fixup_nodatasum *fixup_nodatasum;
940 WARN_ON(sctx->is_dev_replace);
943 * !is_metadata and !have_csum, this means that the data
944 * might not be COW'ed, that it might be modified
945 * concurrently. The general strategy to work on the
946 * commit root does not help in the case when COW is not
949 fixup_nodatasum = kzalloc(sizeof(*fixup_nodatasum), GFP_NOFS);
950 if (!fixup_nodatasum)
951 goto did_not_correct_error;
952 fixup_nodatasum->sctx = sctx;
953 fixup_nodatasum->dev = dev;
954 fixup_nodatasum->logical = logical;
955 fixup_nodatasum->root = fs_info->extent_root;
956 fixup_nodatasum->mirror_num = failed_mirror_index + 1;
957 scrub_pending_trans_workers_inc(sctx);
958 fixup_nodatasum->work.func = scrub_fixup_nodatasum;
959 btrfs_queue_worker(&fs_info->scrub_workers,
960 &fixup_nodatasum->work);
965 * now build and submit the bios for the other mirrors, check
967 * First try to pick the mirror which is completely without I/O
968 * errors and also does not have a checksum error.
969 * If one is found, and if a checksum is present, the full block
970 * that is known to contain an error is rewritten. Afterwards
971 * the block is known to be corrected.
972 * If a mirror is found which is completely correct, and no
973 * checksum is present, only those pages are rewritten that had
974 * an I/O error in the block to be repaired, since it cannot be
975 * determined, which copy of the other pages is better (and it
976 * could happen otherwise that a correct page would be
977 * overwritten by a bad one).
979 for (mirror_index = 0;
980 mirror_index < BTRFS_MAX_MIRRORS &&
981 sblocks_for_recheck[mirror_index].page_count > 0;
983 struct scrub_block *sblock_other;
985 if (mirror_index == failed_mirror_index)
987 sblock_other = sblocks_for_recheck + mirror_index;
989 /* build and submit the bios, check checksums */
990 scrub_recheck_block(fs_info, sblock_other, is_metadata,
991 have_csum, csum, generation,
994 if (!sblock_other->header_error &&
995 !sblock_other->checksum_error &&
996 sblock_other->no_io_error_seen) {
997 if (sctx->is_dev_replace) {
998 scrub_write_block_to_dev_replace(sblock_other);
1000 int force_write = is_metadata || have_csum;
1002 ret = scrub_repair_block_from_good_copy(
1003 sblock_bad, sblock_other,
1007 goto corrected_error;
1012 * for dev_replace, pick good pages and write to the target device.
1014 if (sctx->is_dev_replace) {
1016 for (page_num = 0; page_num < sblock_bad->page_count;
1021 for (mirror_index = 0;
1022 mirror_index < BTRFS_MAX_MIRRORS &&
1023 sblocks_for_recheck[mirror_index].page_count > 0;
1025 struct scrub_block *sblock_other =
1026 sblocks_for_recheck + mirror_index;
1027 struct scrub_page *page_other =
1028 sblock_other->pagev[page_num];
1030 if (!page_other->io_error) {
1031 ret = scrub_write_page_to_dev_replace(
1032 sblock_other, page_num);
1034 /* succeeded for this page */
1038 btrfs_dev_replace_stats_inc(
1040 fs_info->dev_replace.
1048 * did not find a mirror to fetch the page
1049 * from. scrub_write_page_to_dev_replace()
1050 * handles this case (page->io_error), by
1051 * filling the block with zeros before
1052 * submitting the write request
1055 ret = scrub_write_page_to_dev_replace(
1056 sblock_bad, page_num);
1058 btrfs_dev_replace_stats_inc(
1059 &sctx->dev_root->fs_info->
1060 dev_replace.num_write_errors);
1068 * for regular scrub, repair those pages that are errored.
1069 * In case of I/O errors in the area that is supposed to be
1070 * repaired, continue by picking good copies of those pages.
1071 * Select the good pages from mirrors to rewrite bad pages from
1072 * the area to fix. Afterwards verify the checksum of the block
1073 * that is supposed to be repaired. This verification step is
1074 * only done for the purpose of statistic counting and for the
1075 * final scrub report, whether errors remain.
1076 * A perfect algorithm could make use of the checksum and try
1077 * all possible combinations of pages from the different mirrors
1078 * until the checksum verification succeeds. For example, when
1079 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
1080 * of mirror #2 is readable but the final checksum test fails,
1081 * then the 2nd page of mirror #3 could be tried, whether now
1082 * the final checksum succeedes. But this would be a rare
1083 * exception and is therefore not implemented. At least it is
1084 * avoided that the good copy is overwritten.
1085 * A more useful improvement would be to pick the sectors
1086 * without I/O error based on sector sizes (512 bytes on legacy
1087 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
1088 * mirror could be repaired by taking 512 byte of a different
1089 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
1090 * area are unreadable.
1093 /* can only fix I/O errors from here on */
1094 if (sblock_bad->no_io_error_seen)
1095 goto did_not_correct_error;
1098 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1099 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1101 if (!page_bad->io_error)
1104 for (mirror_index = 0;
1105 mirror_index < BTRFS_MAX_MIRRORS &&
1106 sblocks_for_recheck[mirror_index].page_count > 0;
1108 struct scrub_block *sblock_other = sblocks_for_recheck +
1110 struct scrub_page *page_other = sblock_other->pagev[
1113 if (!page_other->io_error) {
1114 ret = scrub_repair_page_from_good_copy(
1115 sblock_bad, sblock_other, page_num, 0);
1117 page_bad->io_error = 0;
1118 break; /* succeeded for this page */
1123 if (page_bad->io_error) {
1124 /* did not find a mirror to copy the page from */
1130 if (is_metadata || have_csum) {
1132 * need to verify the checksum now that all
1133 * sectors on disk are repaired (the write
1134 * request for data to be repaired is on its way).
1135 * Just be lazy and use scrub_recheck_block()
1136 * which re-reads the data before the checksum
1137 * is verified, but most likely the data comes out
1138 * of the page cache.
1140 scrub_recheck_block(fs_info, sblock_bad,
1141 is_metadata, have_csum, csum,
1142 generation, sctx->csum_size);
1143 if (!sblock_bad->header_error &&
1144 !sblock_bad->checksum_error &&
1145 sblock_bad->no_io_error_seen)
1146 goto corrected_error;
1148 goto did_not_correct_error;
1151 spin_lock(&sctx->stat_lock);
1152 sctx->stat.corrected_errors++;
1153 spin_unlock(&sctx->stat_lock);
1154 printk_ratelimited_in_rcu(KERN_ERR
1155 "btrfs: fixed up error at logical %llu on dev %s\n",
1156 (unsigned long long)logical,
1157 rcu_str_deref(dev->name));
1160 did_not_correct_error:
1161 spin_lock(&sctx->stat_lock);
1162 sctx->stat.uncorrectable_errors++;
1163 spin_unlock(&sctx->stat_lock);
1164 printk_ratelimited_in_rcu(KERN_ERR
1165 "btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
1166 (unsigned long long)logical,
1167 rcu_str_deref(dev->name));
1171 if (sblocks_for_recheck) {
1172 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
1174 struct scrub_block *sblock = sblocks_for_recheck +
1178 for (page_index = 0; page_index < sblock->page_count;
1180 sblock->pagev[page_index]->sblock = NULL;
1181 scrub_page_put(sblock->pagev[page_index]);
1184 kfree(sblocks_for_recheck);
1190 static int scrub_setup_recheck_block(struct scrub_ctx *sctx,
1191 struct btrfs_fs_info *fs_info,
1192 struct scrub_block *original_sblock,
1193 u64 length, u64 logical,
1194 struct scrub_block *sblocks_for_recheck)
1201 * note: the two members ref_count and outstanding_pages
1202 * are not used (and not set) in the blocks that are used for
1203 * the recheck procedure
1207 while (length > 0) {
1208 u64 sublen = min_t(u64, length, PAGE_SIZE);
1209 u64 mapped_length = sublen;
1210 struct btrfs_bio *bbio = NULL;
1213 * with a length of PAGE_SIZE, each returned stripe
1214 * represents one mirror
1216 ret = btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, logical,
1217 &mapped_length, &bbio, 0);
1218 if (ret || !bbio || mapped_length < sublen) {
1223 BUG_ON(page_index >= SCRUB_PAGES_PER_RD_BIO);
1224 for (mirror_index = 0; mirror_index < (int)bbio->num_stripes;
1226 struct scrub_block *sblock;
1227 struct scrub_page *page;
1229 if (mirror_index >= BTRFS_MAX_MIRRORS)
1232 sblock = sblocks_for_recheck + mirror_index;
1233 sblock->sctx = sctx;
1234 page = kzalloc(sizeof(*page), GFP_NOFS);
1237 spin_lock(&sctx->stat_lock);
1238 sctx->stat.malloc_errors++;
1239 spin_unlock(&sctx->stat_lock);
1243 scrub_page_get(page);
1244 sblock->pagev[page_index] = page;
1245 page->logical = logical;
1246 page->physical = bbio->stripes[mirror_index].physical;
1247 BUG_ON(page_index >= original_sblock->page_count);
1248 page->physical_for_dev_replace =
1249 original_sblock->pagev[page_index]->
1250 physical_for_dev_replace;
1251 /* for missing devices, dev->bdev is NULL */
1252 page->dev = bbio->stripes[mirror_index].dev;
1253 page->mirror_num = mirror_index + 1;
1254 sblock->page_count++;
1255 page->page = alloc_page(GFP_NOFS);
1269 * this function will check the on disk data for checksum errors, header
1270 * errors and read I/O errors. If any I/O errors happen, the exact pages
1271 * which are errored are marked as being bad. The goal is to enable scrub
1272 * to take those pages that are not errored from all the mirrors so that
1273 * the pages that are errored in the just handled mirror can be repaired.
1275 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
1276 struct scrub_block *sblock, int is_metadata,
1277 int have_csum, u8 *csum, u64 generation,
1282 sblock->no_io_error_seen = 1;
1283 sblock->header_error = 0;
1284 sblock->checksum_error = 0;
1286 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1288 struct scrub_page *page = sblock->pagev[page_num];
1289 DECLARE_COMPLETION_ONSTACK(complete);
1291 if (page->dev->bdev == NULL) {
1293 sblock->no_io_error_seen = 0;
1297 WARN_ON(!page->page);
1298 bio = bio_alloc(GFP_NOFS, 1);
1301 sblock->no_io_error_seen = 0;
1304 bio->bi_bdev = page->dev->bdev;
1305 bio->bi_sector = page->physical >> 9;
1306 bio->bi_end_io = scrub_complete_bio_end_io;
1307 bio->bi_private = &complete;
1309 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1310 btrfsic_submit_bio(READ, bio);
1312 /* this will also unplug the queue */
1313 wait_for_completion(&complete);
1315 page->io_error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
1316 if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
1317 sblock->no_io_error_seen = 0;
1321 if (sblock->no_io_error_seen)
1322 scrub_recheck_block_checksum(fs_info, sblock, is_metadata,
1323 have_csum, csum, generation,
1329 static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
1330 struct scrub_block *sblock,
1331 int is_metadata, int have_csum,
1332 const u8 *csum, u64 generation,
1336 u8 calculated_csum[BTRFS_CSUM_SIZE];
1338 struct btrfs_root *root = fs_info->extent_root;
1339 void *mapped_buffer;
1341 WARN_ON(!sblock->pagev[0]->page);
1343 struct btrfs_header *h;
1345 mapped_buffer = kmap_atomic(sblock->pagev[0]->page);
1346 h = (struct btrfs_header *)mapped_buffer;
1348 if (sblock->pagev[0]->logical != le64_to_cpu(h->bytenr) ||
1349 memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE) ||
1350 memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1352 sblock->header_error = 1;
1353 } else if (generation != le64_to_cpu(h->generation)) {
1354 sblock->header_error = 1;
1355 sblock->generation_error = 1;
1362 mapped_buffer = kmap_atomic(sblock->pagev[0]->page);
1365 for (page_num = 0;;) {
1366 if (page_num == 0 && is_metadata)
1367 crc = btrfs_csum_data(root,
1368 ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE,
1369 crc, PAGE_SIZE - BTRFS_CSUM_SIZE);
1371 crc = btrfs_csum_data(root, mapped_buffer, crc,
1374 kunmap_atomic(mapped_buffer);
1376 if (page_num >= sblock->page_count)
1378 WARN_ON(!sblock->pagev[page_num]->page);
1380 mapped_buffer = kmap_atomic(sblock->pagev[page_num]->page);
1383 btrfs_csum_final(crc, calculated_csum);
1384 if (memcmp(calculated_csum, csum, csum_size))
1385 sblock->checksum_error = 1;
1388 static void scrub_complete_bio_end_io(struct bio *bio, int err)
1390 complete((struct completion *)bio->bi_private);
1393 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1394 struct scrub_block *sblock_good,
1400 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1403 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1414 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1415 struct scrub_block *sblock_good,
1416 int page_num, int force_write)
1418 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1419 struct scrub_page *page_good = sblock_good->pagev[page_num];
1421 BUG_ON(page_bad->page == NULL);
1422 BUG_ON(page_good->page == NULL);
1423 if (force_write || sblock_bad->header_error ||
1424 sblock_bad->checksum_error || page_bad->io_error) {
1427 DECLARE_COMPLETION_ONSTACK(complete);
1429 if (!page_bad->dev->bdev) {
1430 printk_ratelimited(KERN_WARNING
1431 "btrfs: scrub_repair_page_from_good_copy(bdev == NULL) is unexpected!\n");
1435 bio = bio_alloc(GFP_NOFS, 1);
1438 bio->bi_bdev = page_bad->dev->bdev;
1439 bio->bi_sector = page_bad->physical >> 9;
1440 bio->bi_end_io = scrub_complete_bio_end_io;
1441 bio->bi_private = &complete;
1443 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1444 if (PAGE_SIZE != ret) {
1448 btrfsic_submit_bio(WRITE, bio);
1450 /* this will also unplug the queue */
1451 wait_for_completion(&complete);
1452 if (!bio_flagged(bio, BIO_UPTODATE)) {
1453 btrfs_dev_stat_inc_and_print(page_bad->dev,
1454 BTRFS_DEV_STAT_WRITE_ERRS);
1455 btrfs_dev_replace_stats_inc(
1456 &sblock_bad->sctx->dev_root->fs_info->
1457 dev_replace.num_write_errors);
1467 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
1471 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1474 ret = scrub_write_page_to_dev_replace(sblock, page_num);
1476 btrfs_dev_replace_stats_inc(
1477 &sblock->sctx->dev_root->fs_info->dev_replace.
1482 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
1485 struct scrub_page *spage = sblock->pagev[page_num];
1487 BUG_ON(spage->page == NULL);
1488 if (spage->io_error) {
1489 void *mapped_buffer = kmap_atomic(spage->page);
1491 memset(mapped_buffer, 0, PAGE_CACHE_SIZE);
1492 flush_dcache_page(spage->page);
1493 kunmap_atomic(mapped_buffer);
1495 return scrub_add_page_to_wr_bio(sblock->sctx, spage);
1498 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
1499 struct scrub_page *spage)
1501 struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx;
1502 struct scrub_bio *sbio;
1505 mutex_lock(&wr_ctx->wr_lock);
1507 if (!wr_ctx->wr_curr_bio) {
1508 wr_ctx->wr_curr_bio = kzalloc(sizeof(*wr_ctx->wr_curr_bio),
1510 if (!wr_ctx->wr_curr_bio) {
1511 mutex_unlock(&wr_ctx->wr_lock);
1514 wr_ctx->wr_curr_bio->sctx = sctx;
1515 wr_ctx->wr_curr_bio->page_count = 0;
1517 sbio = wr_ctx->wr_curr_bio;
1518 if (sbio->page_count == 0) {
1521 sbio->physical = spage->physical_for_dev_replace;
1522 sbio->logical = spage->logical;
1523 sbio->dev = wr_ctx->tgtdev;
1526 bio = bio_alloc(GFP_NOFS, wr_ctx->pages_per_wr_bio);
1528 mutex_unlock(&wr_ctx->wr_lock);
1534 bio->bi_private = sbio;
1535 bio->bi_end_io = scrub_wr_bio_end_io;
1536 bio->bi_bdev = sbio->dev->bdev;
1537 bio->bi_sector = sbio->physical >> 9;
1539 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1540 spage->physical_for_dev_replace ||
1541 sbio->logical + sbio->page_count * PAGE_SIZE !=
1543 scrub_wr_submit(sctx);
1547 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1548 if (ret != PAGE_SIZE) {
1549 if (sbio->page_count < 1) {
1552 mutex_unlock(&wr_ctx->wr_lock);
1555 scrub_wr_submit(sctx);
1559 sbio->pagev[sbio->page_count] = spage;
1560 scrub_page_get(spage);
1562 if (sbio->page_count == wr_ctx->pages_per_wr_bio)
1563 scrub_wr_submit(sctx);
1564 mutex_unlock(&wr_ctx->wr_lock);
1569 static void scrub_wr_submit(struct scrub_ctx *sctx)
1571 struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx;
1572 struct scrub_bio *sbio;
1574 if (!wr_ctx->wr_curr_bio)
1577 sbio = wr_ctx->wr_curr_bio;
1578 wr_ctx->wr_curr_bio = NULL;
1579 WARN_ON(!sbio->bio->bi_bdev);
1580 scrub_pending_bio_inc(sctx);
1581 /* process all writes in a single worker thread. Then the block layer
1582 * orders the requests before sending them to the driver which
1583 * doubled the write performance on spinning disks when measured
1585 btrfsic_submit_bio(WRITE, sbio->bio);
1588 static void scrub_wr_bio_end_io(struct bio *bio, int err)
1590 struct scrub_bio *sbio = bio->bi_private;
1591 struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info;
1596 sbio->work.func = scrub_wr_bio_end_io_worker;
1597 btrfs_queue_worker(&fs_info->scrub_wr_completion_workers, &sbio->work);
1600 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work)
1602 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1603 struct scrub_ctx *sctx = sbio->sctx;
1606 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO);
1608 struct btrfs_dev_replace *dev_replace =
1609 &sbio->sctx->dev_root->fs_info->dev_replace;
1611 for (i = 0; i < sbio->page_count; i++) {
1612 struct scrub_page *spage = sbio->pagev[i];
1614 spage->io_error = 1;
1615 btrfs_dev_replace_stats_inc(&dev_replace->
1620 for (i = 0; i < sbio->page_count; i++)
1621 scrub_page_put(sbio->pagev[i]);
1625 scrub_pending_bio_dec(sctx);
1628 static int scrub_checksum(struct scrub_block *sblock)
1633 WARN_ON(sblock->page_count < 1);
1634 flags = sblock->pagev[0]->flags;
1636 if (flags & BTRFS_EXTENT_FLAG_DATA)
1637 ret = scrub_checksum_data(sblock);
1638 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1639 ret = scrub_checksum_tree_block(sblock);
1640 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1641 (void)scrub_checksum_super(sblock);
1645 scrub_handle_errored_block(sblock);
1650 static int scrub_checksum_data(struct scrub_block *sblock)
1652 struct scrub_ctx *sctx = sblock->sctx;
1653 u8 csum[BTRFS_CSUM_SIZE];
1659 struct btrfs_root *root = sctx->dev_root;
1663 BUG_ON(sblock->page_count < 1);
1664 if (!sblock->pagev[0]->have_csum)
1667 on_disk_csum = sblock->pagev[0]->csum;
1668 page = sblock->pagev[0]->page;
1669 buffer = kmap_atomic(page);
1671 len = sctx->sectorsize;
1674 u64 l = min_t(u64, len, PAGE_SIZE);
1676 crc = btrfs_csum_data(root, buffer, crc, l);
1677 kunmap_atomic(buffer);
1682 BUG_ON(index >= sblock->page_count);
1683 BUG_ON(!sblock->pagev[index]->page);
1684 page = sblock->pagev[index]->page;
1685 buffer = kmap_atomic(page);
1688 btrfs_csum_final(crc, csum);
1689 if (memcmp(csum, on_disk_csum, sctx->csum_size))
1695 static int scrub_checksum_tree_block(struct scrub_block *sblock)
1697 struct scrub_ctx *sctx = sblock->sctx;
1698 struct btrfs_header *h;
1699 struct btrfs_root *root = sctx->dev_root;
1700 struct btrfs_fs_info *fs_info = root->fs_info;
1701 u8 calculated_csum[BTRFS_CSUM_SIZE];
1702 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1704 void *mapped_buffer;
1713 BUG_ON(sblock->page_count < 1);
1714 page = sblock->pagev[0]->page;
1715 mapped_buffer = kmap_atomic(page);
1716 h = (struct btrfs_header *)mapped_buffer;
1717 memcpy(on_disk_csum, h->csum, sctx->csum_size);
1720 * we don't use the getter functions here, as we
1721 * a) don't have an extent buffer and
1722 * b) the page is already kmapped
1725 if (sblock->pagev[0]->logical != le64_to_cpu(h->bytenr))
1728 if (sblock->pagev[0]->generation != le64_to_cpu(h->generation))
1731 if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1734 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1738 WARN_ON(sctx->nodesize != sctx->leafsize);
1739 len = sctx->nodesize - BTRFS_CSUM_SIZE;
1740 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1741 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1744 u64 l = min_t(u64, len, mapped_size);
1746 crc = btrfs_csum_data(root, p, crc, l);
1747 kunmap_atomic(mapped_buffer);
1752 BUG_ON(index >= sblock->page_count);
1753 BUG_ON(!sblock->pagev[index]->page);
1754 page = sblock->pagev[index]->page;
1755 mapped_buffer = kmap_atomic(page);
1756 mapped_size = PAGE_SIZE;
1760 btrfs_csum_final(crc, calculated_csum);
1761 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1764 return fail || crc_fail;
1767 static int scrub_checksum_super(struct scrub_block *sblock)
1769 struct btrfs_super_block *s;
1770 struct scrub_ctx *sctx = sblock->sctx;
1771 struct btrfs_root *root = sctx->dev_root;
1772 struct btrfs_fs_info *fs_info = root->fs_info;
1773 u8 calculated_csum[BTRFS_CSUM_SIZE];
1774 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1776 void *mapped_buffer;
1785 BUG_ON(sblock->page_count < 1);
1786 page = sblock->pagev[0]->page;
1787 mapped_buffer = kmap_atomic(page);
1788 s = (struct btrfs_super_block *)mapped_buffer;
1789 memcpy(on_disk_csum, s->csum, sctx->csum_size);
1791 if (sblock->pagev[0]->logical != le64_to_cpu(s->bytenr))
1794 if (sblock->pagev[0]->generation != le64_to_cpu(s->generation))
1797 if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1800 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1801 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1802 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1805 u64 l = min_t(u64, len, mapped_size);
1807 crc = btrfs_csum_data(root, p, crc, l);
1808 kunmap_atomic(mapped_buffer);
1813 BUG_ON(index >= sblock->page_count);
1814 BUG_ON(!sblock->pagev[index]->page);
1815 page = sblock->pagev[index]->page;
1816 mapped_buffer = kmap_atomic(page);
1817 mapped_size = PAGE_SIZE;
1821 btrfs_csum_final(crc, calculated_csum);
1822 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1825 if (fail_cor + fail_gen) {
1827 * if we find an error in a super block, we just report it.
1828 * They will get written with the next transaction commit
1831 spin_lock(&sctx->stat_lock);
1832 ++sctx->stat.super_errors;
1833 spin_unlock(&sctx->stat_lock);
1835 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1836 BTRFS_DEV_STAT_CORRUPTION_ERRS);
1838 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1839 BTRFS_DEV_STAT_GENERATION_ERRS);
1842 return fail_cor + fail_gen;
1845 static void scrub_block_get(struct scrub_block *sblock)
1847 atomic_inc(&sblock->ref_count);
1850 static void scrub_block_put(struct scrub_block *sblock)
1852 if (atomic_dec_and_test(&sblock->ref_count)) {
1855 for (i = 0; i < sblock->page_count; i++)
1856 scrub_page_put(sblock->pagev[i]);
1861 static void scrub_page_get(struct scrub_page *spage)
1863 atomic_inc(&spage->ref_count);
1866 static void scrub_page_put(struct scrub_page *spage)
1868 if (atomic_dec_and_test(&spage->ref_count)) {
1870 __free_page(spage->page);
1875 static void scrub_submit(struct scrub_ctx *sctx)
1877 struct scrub_bio *sbio;
1879 if (sctx->curr == -1)
1882 sbio = sctx->bios[sctx->curr];
1884 scrub_pending_bio_inc(sctx);
1886 if (!sbio->bio->bi_bdev) {
1888 * this case should not happen. If btrfs_map_block() is
1889 * wrong, it could happen for dev-replace operations on
1890 * missing devices when no mirrors are available, but in
1891 * this case it should already fail the mount.
1892 * This case is handled correctly (but _very_ slowly).
1894 printk_ratelimited(KERN_WARNING
1895 "btrfs: scrub_submit(bio bdev == NULL) is unexpected!\n");
1896 bio_endio(sbio->bio, -EIO);
1898 btrfsic_submit_bio(READ, sbio->bio);
1902 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
1903 struct scrub_page *spage)
1905 struct scrub_block *sblock = spage->sblock;
1906 struct scrub_bio *sbio;
1911 * grab a fresh bio or wait for one to become available
1913 while (sctx->curr == -1) {
1914 spin_lock(&sctx->list_lock);
1915 sctx->curr = sctx->first_free;
1916 if (sctx->curr != -1) {
1917 sctx->first_free = sctx->bios[sctx->curr]->next_free;
1918 sctx->bios[sctx->curr]->next_free = -1;
1919 sctx->bios[sctx->curr]->page_count = 0;
1920 spin_unlock(&sctx->list_lock);
1922 spin_unlock(&sctx->list_lock);
1923 wait_event(sctx->list_wait, sctx->first_free != -1);
1926 sbio = sctx->bios[sctx->curr];
1927 if (sbio->page_count == 0) {
1930 sbio->physical = spage->physical;
1931 sbio->logical = spage->logical;
1932 sbio->dev = spage->dev;
1935 bio = bio_alloc(GFP_NOFS, sctx->pages_per_rd_bio);
1941 bio->bi_private = sbio;
1942 bio->bi_end_io = scrub_bio_end_io;
1943 bio->bi_bdev = sbio->dev->bdev;
1944 bio->bi_sector = sbio->physical >> 9;
1946 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1948 sbio->logical + sbio->page_count * PAGE_SIZE !=
1950 sbio->dev != spage->dev) {
1955 sbio->pagev[sbio->page_count] = spage;
1956 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1957 if (ret != PAGE_SIZE) {
1958 if (sbio->page_count < 1) {
1967 scrub_block_get(sblock); /* one for the page added to the bio */
1968 atomic_inc(&sblock->outstanding_pages);
1970 if (sbio->page_count == sctx->pages_per_rd_bio)
1976 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
1977 u64 physical, struct btrfs_device *dev, u64 flags,
1978 u64 gen, int mirror_num, u8 *csum, int force,
1979 u64 physical_for_dev_replace)
1981 struct scrub_block *sblock;
1984 sblock = kzalloc(sizeof(*sblock), GFP_NOFS);
1986 spin_lock(&sctx->stat_lock);
1987 sctx->stat.malloc_errors++;
1988 spin_unlock(&sctx->stat_lock);
1992 /* one ref inside this function, plus one for each page added to
1994 atomic_set(&sblock->ref_count, 1);
1995 sblock->sctx = sctx;
1996 sblock->no_io_error_seen = 1;
1998 for (index = 0; len > 0; index++) {
1999 struct scrub_page *spage;
2000 u64 l = min_t(u64, len, PAGE_SIZE);
2002 spage = kzalloc(sizeof(*spage), GFP_NOFS);
2005 spin_lock(&sctx->stat_lock);
2006 sctx->stat.malloc_errors++;
2007 spin_unlock(&sctx->stat_lock);
2008 scrub_block_put(sblock);
2011 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2012 scrub_page_get(spage);
2013 sblock->pagev[index] = spage;
2014 spage->sblock = sblock;
2016 spage->flags = flags;
2017 spage->generation = gen;
2018 spage->logical = logical;
2019 spage->physical = physical;
2020 spage->physical_for_dev_replace = physical_for_dev_replace;
2021 spage->mirror_num = mirror_num;
2023 spage->have_csum = 1;
2024 memcpy(spage->csum, csum, sctx->csum_size);
2026 spage->have_csum = 0;
2028 sblock->page_count++;
2029 spage->page = alloc_page(GFP_NOFS);
2035 physical_for_dev_replace += l;
2038 WARN_ON(sblock->page_count == 0);
2039 for (index = 0; index < sblock->page_count; index++) {
2040 struct scrub_page *spage = sblock->pagev[index];
2043 ret = scrub_add_page_to_rd_bio(sctx, spage);
2045 scrub_block_put(sblock);
2053 /* last one frees, either here or in bio completion for last page */
2054 scrub_block_put(sblock);
2058 static void scrub_bio_end_io(struct bio *bio, int err)
2060 struct scrub_bio *sbio = bio->bi_private;
2061 struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info;
2066 btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work);
2069 static void scrub_bio_end_io_worker(struct btrfs_work *work)
2071 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
2072 struct scrub_ctx *sctx = sbio->sctx;
2075 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO);
2077 for (i = 0; i < sbio->page_count; i++) {
2078 struct scrub_page *spage = sbio->pagev[i];
2080 spage->io_error = 1;
2081 spage->sblock->no_io_error_seen = 0;
2085 /* now complete the scrub_block items that have all pages completed */
2086 for (i = 0; i < sbio->page_count; i++) {
2087 struct scrub_page *spage = sbio->pagev[i];
2088 struct scrub_block *sblock = spage->sblock;
2090 if (atomic_dec_and_test(&sblock->outstanding_pages))
2091 scrub_block_complete(sblock);
2092 scrub_block_put(sblock);
2097 spin_lock(&sctx->list_lock);
2098 sbio->next_free = sctx->first_free;
2099 sctx->first_free = sbio->index;
2100 spin_unlock(&sctx->list_lock);
2102 if (sctx->is_dev_replace &&
2103 atomic_read(&sctx->wr_ctx.flush_all_writes)) {
2104 mutex_lock(&sctx->wr_ctx.wr_lock);
2105 scrub_wr_submit(sctx);
2106 mutex_unlock(&sctx->wr_ctx.wr_lock);
2109 scrub_pending_bio_dec(sctx);
2112 static void scrub_block_complete(struct scrub_block *sblock)
2114 if (!sblock->no_io_error_seen) {
2115 scrub_handle_errored_block(sblock);
2118 * if has checksum error, write via repair mechanism in
2119 * dev replace case, otherwise write here in dev replace
2122 if (!scrub_checksum(sblock) && sblock->sctx->is_dev_replace)
2123 scrub_write_block_to_dev_replace(sblock);
2127 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u64 len,
2130 struct btrfs_ordered_sum *sum = NULL;
2133 unsigned long num_sectors;
2135 while (!list_empty(&sctx->csum_list)) {
2136 sum = list_first_entry(&sctx->csum_list,
2137 struct btrfs_ordered_sum, list);
2138 if (sum->bytenr > logical)
2140 if (sum->bytenr + sum->len > logical)
2143 ++sctx->stat.csum_discards;
2144 list_del(&sum->list);
2151 num_sectors = sum->len / sctx->sectorsize;
2152 for (i = 0; i < num_sectors; ++i) {
2153 if (sum->sums[i].bytenr == logical) {
2154 memcpy(csum, &sum->sums[i].sum, sctx->csum_size);
2159 if (ret && i == num_sectors - 1) {
2160 list_del(&sum->list);
2166 /* scrub extent tries to collect up to 64 kB for each bio */
2167 static int scrub_extent(struct scrub_ctx *sctx, u64 logical, u64 len,
2168 u64 physical, struct btrfs_device *dev, u64 flags,
2169 u64 gen, int mirror_num, u64 physical_for_dev_replace)
2172 u8 csum[BTRFS_CSUM_SIZE];
2175 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2176 blocksize = sctx->sectorsize;
2177 spin_lock(&sctx->stat_lock);
2178 sctx->stat.data_extents_scrubbed++;
2179 sctx->stat.data_bytes_scrubbed += len;
2180 spin_unlock(&sctx->stat_lock);
2181 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2182 WARN_ON(sctx->nodesize != sctx->leafsize);
2183 blocksize = sctx->nodesize;
2184 spin_lock(&sctx->stat_lock);
2185 sctx->stat.tree_extents_scrubbed++;
2186 sctx->stat.tree_bytes_scrubbed += len;
2187 spin_unlock(&sctx->stat_lock);
2189 blocksize = sctx->sectorsize;
2194 u64 l = min_t(u64, len, blocksize);
2197 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2198 /* push csums to sbio */
2199 have_csum = scrub_find_csum(sctx, logical, l, csum);
2201 ++sctx->stat.no_csum;
2202 if (sctx->is_dev_replace && !have_csum) {
2203 ret = copy_nocow_pages(sctx, logical, l,
2205 physical_for_dev_replace);
2206 goto behind_scrub_pages;
2209 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen,
2210 mirror_num, have_csum ? csum : NULL, 0,
2211 physical_for_dev_replace);
2218 physical_for_dev_replace += l;
2223 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
2224 struct map_lookup *map,
2225 struct btrfs_device *scrub_dev,
2226 int num, u64 base, u64 length,
2229 struct btrfs_path *path;
2230 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
2231 struct btrfs_root *root = fs_info->extent_root;
2232 struct btrfs_root *csum_root = fs_info->csum_root;
2233 struct btrfs_extent_item *extent;
2234 struct blk_plug plug;
2240 struct extent_buffer *l;
2241 struct btrfs_key key;
2246 struct reada_control *reada1;
2247 struct reada_control *reada2;
2248 struct btrfs_key key_start;
2249 struct btrfs_key key_end;
2250 u64 increment = map->stripe_len;
2253 u64 extent_physical;
2255 struct btrfs_device *extent_dev;
2256 int extent_mirror_num;
2258 if (map->type & (BTRFS_BLOCK_GROUP_RAID5 |
2259 BTRFS_BLOCK_GROUP_RAID6)) {
2260 if (num >= nr_data_stripes(map)) {
2267 do_div(nstripes, map->stripe_len);
2268 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
2269 offset = map->stripe_len * num;
2270 increment = map->stripe_len * map->num_stripes;
2272 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2273 int factor = map->num_stripes / map->sub_stripes;
2274 offset = map->stripe_len * (num / map->sub_stripes);
2275 increment = map->stripe_len * factor;
2276 mirror_num = num % map->sub_stripes + 1;
2277 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
2278 increment = map->stripe_len;
2279 mirror_num = num % map->num_stripes + 1;
2280 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
2281 increment = map->stripe_len;
2282 mirror_num = num % map->num_stripes + 1;
2284 increment = map->stripe_len;
2288 path = btrfs_alloc_path();
2293 * work on commit root. The related disk blocks are static as
2294 * long as COW is applied. This means, it is save to rewrite
2295 * them to repair disk errors without any race conditions
2297 path->search_commit_root = 1;
2298 path->skip_locking = 1;
2301 * trigger the readahead for extent tree csum tree and wait for
2302 * completion. During readahead, the scrub is officially paused
2303 * to not hold off transaction commits
2305 logical = base + offset;
2307 wait_event(sctx->list_wait,
2308 atomic_read(&sctx->bios_in_flight) == 0);
2309 atomic_inc(&fs_info->scrubs_paused);
2310 wake_up(&fs_info->scrub_pause_wait);
2312 /* FIXME it might be better to start readahead at commit root */
2313 key_start.objectid = logical;
2314 key_start.type = BTRFS_EXTENT_ITEM_KEY;
2315 key_start.offset = (u64)0;
2316 key_end.objectid = base + offset + nstripes * increment;
2317 key_end.type = BTRFS_EXTENT_ITEM_KEY;
2318 key_end.offset = (u64)0;
2319 reada1 = btrfs_reada_add(root, &key_start, &key_end);
2321 key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
2322 key_start.type = BTRFS_EXTENT_CSUM_KEY;
2323 key_start.offset = logical;
2324 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
2325 key_end.type = BTRFS_EXTENT_CSUM_KEY;
2326 key_end.offset = base + offset + nstripes * increment;
2327 reada2 = btrfs_reada_add(csum_root, &key_start, &key_end);
2329 if (!IS_ERR(reada1))
2330 btrfs_reada_wait(reada1);
2331 if (!IS_ERR(reada2))
2332 btrfs_reada_wait(reada2);
2334 mutex_lock(&fs_info->scrub_lock);
2335 while (atomic_read(&fs_info->scrub_pause_req)) {
2336 mutex_unlock(&fs_info->scrub_lock);
2337 wait_event(fs_info->scrub_pause_wait,
2338 atomic_read(&fs_info->scrub_pause_req) == 0);
2339 mutex_lock(&fs_info->scrub_lock);
2341 atomic_dec(&fs_info->scrubs_paused);
2342 mutex_unlock(&fs_info->scrub_lock);
2343 wake_up(&fs_info->scrub_pause_wait);
2346 * collect all data csums for the stripe to avoid seeking during
2347 * the scrub. This might currently (crc32) end up to be about 1MB
2349 blk_start_plug(&plug);
2352 * now find all extents for each stripe and scrub them
2354 logical = base + offset;
2355 physical = map->stripes[num].physical;
2357 for (i = 0; i < nstripes; ++i) {
2361 if (atomic_read(&fs_info->scrub_cancel_req) ||
2362 atomic_read(&sctx->cancel_req)) {
2367 * check to see if we have to pause
2369 if (atomic_read(&fs_info->scrub_pause_req)) {
2370 /* push queued extents */
2371 atomic_set(&sctx->wr_ctx.flush_all_writes, 1);
2373 mutex_lock(&sctx->wr_ctx.wr_lock);
2374 scrub_wr_submit(sctx);
2375 mutex_unlock(&sctx->wr_ctx.wr_lock);
2376 wait_event(sctx->list_wait,
2377 atomic_read(&sctx->bios_in_flight) == 0);
2378 atomic_set(&sctx->wr_ctx.flush_all_writes, 0);
2379 atomic_inc(&fs_info->scrubs_paused);
2380 wake_up(&fs_info->scrub_pause_wait);
2381 mutex_lock(&fs_info->scrub_lock);
2382 while (atomic_read(&fs_info->scrub_pause_req)) {
2383 mutex_unlock(&fs_info->scrub_lock);
2384 wait_event(fs_info->scrub_pause_wait,
2385 atomic_read(&fs_info->scrub_pause_req) == 0);
2386 mutex_lock(&fs_info->scrub_lock);
2388 atomic_dec(&fs_info->scrubs_paused);
2389 mutex_unlock(&fs_info->scrub_lock);
2390 wake_up(&fs_info->scrub_pause_wait);
2393 ret = btrfs_lookup_csums_range(csum_root, logical,
2394 logical + map->stripe_len - 1,
2395 &sctx->csum_list, 1);
2399 key.objectid = logical;
2400 key.type = BTRFS_EXTENT_ITEM_KEY;
2401 key.offset = (u64)0;
2403 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2407 ret = btrfs_previous_item(root, path, 0,
2408 BTRFS_EXTENT_ITEM_KEY);
2412 /* there's no smaller item, so stick with the
2414 btrfs_release_path(path);
2415 ret = btrfs_search_slot(NULL, root, &key,
2424 slot = path->slots[0];
2425 if (slot >= btrfs_header_nritems(l)) {
2426 ret = btrfs_next_leaf(root, path);
2434 btrfs_item_key_to_cpu(l, &key, slot);
2436 if (key.objectid + key.offset <= logical)
2439 if (key.objectid >= logical + map->stripe_len)
2442 if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
2445 extent = btrfs_item_ptr(l, slot,
2446 struct btrfs_extent_item);
2447 flags = btrfs_extent_flags(l, extent);
2448 generation = btrfs_extent_generation(l, extent);
2450 if (key.objectid < logical &&
2451 (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
2453 "btrfs scrub: tree block %llu spanning "
2454 "stripes, ignored. logical=%llu\n",
2455 (unsigned long long)key.objectid,
2456 (unsigned long long)logical);
2461 * trim extent to this stripe
2463 if (key.objectid < logical) {
2464 key.offset -= logical - key.objectid;
2465 key.objectid = logical;
2467 if (key.objectid + key.offset >
2468 logical + map->stripe_len) {
2469 key.offset = logical + map->stripe_len -
2473 extent_logical = key.objectid;
2474 extent_physical = key.objectid - logical + physical;
2475 extent_len = key.offset;
2476 extent_dev = scrub_dev;
2477 extent_mirror_num = mirror_num;
2479 scrub_remap_extent(fs_info, extent_logical,
2480 extent_len, &extent_physical,
2482 &extent_mirror_num);
2483 ret = scrub_extent(sctx, extent_logical, extent_len,
2484 extent_physical, extent_dev, flags,
2485 generation, extent_mirror_num,
2486 key.objectid - logical + physical);
2493 btrfs_release_path(path);
2494 logical += increment;
2495 physical += map->stripe_len;
2496 spin_lock(&sctx->stat_lock);
2497 sctx->stat.last_physical = physical;
2498 spin_unlock(&sctx->stat_lock);
2501 /* push queued extents */
2503 mutex_lock(&sctx->wr_ctx.wr_lock);
2504 scrub_wr_submit(sctx);
2505 mutex_unlock(&sctx->wr_ctx.wr_lock);
2507 blk_finish_plug(&plug);
2508 btrfs_free_path(path);
2509 return ret < 0 ? ret : 0;
2512 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
2513 struct btrfs_device *scrub_dev,
2514 u64 chunk_tree, u64 chunk_objectid,
2515 u64 chunk_offset, u64 length,
2516 u64 dev_offset, int is_dev_replace)
2518 struct btrfs_mapping_tree *map_tree =
2519 &sctx->dev_root->fs_info->mapping_tree;
2520 struct map_lookup *map;
2521 struct extent_map *em;
2525 read_lock(&map_tree->map_tree.lock);
2526 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
2527 read_unlock(&map_tree->map_tree.lock);
2532 map = (struct map_lookup *)em->bdev;
2533 if (em->start != chunk_offset)
2536 if (em->len < length)
2539 for (i = 0; i < map->num_stripes; ++i) {
2540 if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
2541 map->stripes[i].physical == dev_offset) {
2542 ret = scrub_stripe(sctx, map, scrub_dev, i,
2543 chunk_offset, length,
2550 free_extent_map(em);
2555 static noinline_for_stack
2556 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
2557 struct btrfs_device *scrub_dev, u64 start, u64 end,
2560 struct btrfs_dev_extent *dev_extent = NULL;
2561 struct btrfs_path *path;
2562 struct btrfs_root *root = sctx->dev_root;
2563 struct btrfs_fs_info *fs_info = root->fs_info;
2570 struct extent_buffer *l;
2571 struct btrfs_key key;
2572 struct btrfs_key found_key;
2573 struct btrfs_block_group_cache *cache;
2574 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
2576 path = btrfs_alloc_path();
2581 path->search_commit_root = 1;
2582 path->skip_locking = 1;
2584 key.objectid = scrub_dev->devid;
2586 key.type = BTRFS_DEV_EXTENT_KEY;
2589 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2593 if (path->slots[0] >=
2594 btrfs_header_nritems(path->nodes[0])) {
2595 ret = btrfs_next_leaf(root, path);
2602 slot = path->slots[0];
2604 btrfs_item_key_to_cpu(l, &found_key, slot);
2606 if (found_key.objectid != scrub_dev->devid)
2609 if (btrfs_key_type(&found_key) != BTRFS_DEV_EXTENT_KEY)
2612 if (found_key.offset >= end)
2615 if (found_key.offset < key.offset)
2618 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2619 length = btrfs_dev_extent_length(l, dev_extent);
2621 if (found_key.offset + length <= start) {
2622 key.offset = found_key.offset + length;
2623 btrfs_release_path(path);
2627 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2628 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2629 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2632 * get a reference on the corresponding block group to prevent
2633 * the chunk from going away while we scrub it
2635 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2640 dev_replace->cursor_right = found_key.offset + length;
2641 dev_replace->cursor_left = found_key.offset;
2642 dev_replace->item_needs_writeback = 1;
2643 ret = scrub_chunk(sctx, scrub_dev, chunk_tree, chunk_objectid,
2644 chunk_offset, length, found_key.offset,
2648 * flush, submit all pending read and write bios, afterwards
2650 * Note that in the dev replace case, a read request causes
2651 * write requests that are submitted in the read completion
2652 * worker. Therefore in the current situation, it is required
2653 * that all write requests are flushed, so that all read and
2654 * write requests are really completed when bios_in_flight
2657 atomic_set(&sctx->wr_ctx.flush_all_writes, 1);
2659 mutex_lock(&sctx->wr_ctx.wr_lock);
2660 scrub_wr_submit(sctx);
2661 mutex_unlock(&sctx->wr_ctx.wr_lock);
2663 wait_event(sctx->list_wait,
2664 atomic_read(&sctx->bios_in_flight) == 0);
2665 atomic_set(&sctx->wr_ctx.flush_all_writes, 0);
2666 atomic_inc(&fs_info->scrubs_paused);
2667 wake_up(&fs_info->scrub_pause_wait);
2668 wait_event(sctx->list_wait,
2669 atomic_read(&sctx->workers_pending) == 0);
2671 mutex_lock(&fs_info->scrub_lock);
2672 while (atomic_read(&fs_info->scrub_pause_req)) {
2673 mutex_unlock(&fs_info->scrub_lock);
2674 wait_event(fs_info->scrub_pause_wait,
2675 atomic_read(&fs_info->scrub_pause_req) == 0);
2676 mutex_lock(&fs_info->scrub_lock);
2678 atomic_dec(&fs_info->scrubs_paused);
2679 mutex_unlock(&fs_info->scrub_lock);
2680 wake_up(&fs_info->scrub_pause_wait);
2682 dev_replace->cursor_left = dev_replace->cursor_right;
2683 dev_replace->item_needs_writeback = 1;
2684 btrfs_put_block_group(cache);
2687 if (is_dev_replace &&
2688 atomic64_read(&dev_replace->num_write_errors) > 0) {
2692 if (sctx->stat.malloc_errors > 0) {
2697 key.offset = found_key.offset + length;
2698 btrfs_release_path(path);
2701 btrfs_free_path(path);
2704 * ret can still be 1 from search_slot or next_leaf,
2705 * that's not an error
2707 return ret < 0 ? ret : 0;
2710 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
2711 struct btrfs_device *scrub_dev)
2717 struct btrfs_root *root = sctx->dev_root;
2719 if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state))
2722 gen = root->fs_info->last_trans_committed;
2724 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
2725 bytenr = btrfs_sb_offset(i);
2726 if (bytenr + BTRFS_SUPER_INFO_SIZE > scrub_dev->total_bytes)
2729 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
2730 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
2735 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
2741 * get a reference count on fs_info->scrub_workers. start worker if necessary
2743 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
2748 mutex_lock(&fs_info->scrub_lock);
2749 if (fs_info->scrub_workers_refcnt == 0) {
2751 btrfs_init_workers(&fs_info->scrub_workers, "scrub", 1,
2752 &fs_info->generic_worker);
2754 btrfs_init_workers(&fs_info->scrub_workers, "scrub",
2755 fs_info->thread_pool_size,
2756 &fs_info->generic_worker);
2757 fs_info->scrub_workers.idle_thresh = 4;
2758 ret = btrfs_start_workers(&fs_info->scrub_workers);
2761 btrfs_init_workers(&fs_info->scrub_wr_completion_workers,
2763 fs_info->thread_pool_size,
2764 &fs_info->generic_worker);
2765 fs_info->scrub_wr_completion_workers.idle_thresh = 2;
2766 ret = btrfs_start_workers(
2767 &fs_info->scrub_wr_completion_workers);
2770 btrfs_init_workers(&fs_info->scrub_nocow_workers, "scrubnc", 1,
2771 &fs_info->generic_worker);
2772 ret = btrfs_start_workers(&fs_info->scrub_nocow_workers);
2776 ++fs_info->scrub_workers_refcnt;
2778 mutex_unlock(&fs_info->scrub_lock);
2783 static noinline_for_stack void scrub_workers_put(struct btrfs_fs_info *fs_info)
2785 mutex_lock(&fs_info->scrub_lock);
2786 if (--fs_info->scrub_workers_refcnt == 0) {
2787 btrfs_stop_workers(&fs_info->scrub_workers);
2788 btrfs_stop_workers(&fs_info->scrub_wr_completion_workers);
2789 btrfs_stop_workers(&fs_info->scrub_nocow_workers);
2791 WARN_ON(fs_info->scrub_workers_refcnt < 0);
2792 mutex_unlock(&fs_info->scrub_lock);
2795 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
2796 u64 end, struct btrfs_scrub_progress *progress,
2797 int readonly, int is_dev_replace)
2799 struct scrub_ctx *sctx;
2801 struct btrfs_device *dev;
2803 if (btrfs_fs_closing(fs_info))
2807 * check some assumptions
2809 if (fs_info->chunk_root->nodesize != fs_info->chunk_root->leafsize) {
2811 "btrfs_scrub: size assumption nodesize == leafsize (%d == %d) fails\n",
2812 fs_info->chunk_root->nodesize,
2813 fs_info->chunk_root->leafsize);
2817 if (fs_info->chunk_root->nodesize > BTRFS_STRIPE_LEN) {
2819 * in this case scrub is unable to calculate the checksum
2820 * the way scrub is implemented. Do not handle this
2821 * situation at all because it won't ever happen.
2824 "btrfs_scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails\n",
2825 fs_info->chunk_root->nodesize, BTRFS_STRIPE_LEN);
2829 if (fs_info->chunk_root->sectorsize != PAGE_SIZE) {
2830 /* not supported for data w/o checksums */
2832 "btrfs_scrub: size assumption sectorsize != PAGE_SIZE (%d != %lld) fails\n",
2833 fs_info->chunk_root->sectorsize,
2834 (unsigned long long)PAGE_SIZE);
2838 if (fs_info->chunk_root->nodesize >
2839 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK ||
2840 fs_info->chunk_root->sectorsize >
2841 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) {
2843 * would exhaust the array bounds of pagev member in
2844 * struct scrub_block
2846 pr_err("btrfs_scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails\n",
2847 fs_info->chunk_root->nodesize,
2848 SCRUB_MAX_PAGES_PER_BLOCK,
2849 fs_info->chunk_root->sectorsize,
2850 SCRUB_MAX_PAGES_PER_BLOCK);
2854 ret = scrub_workers_get(fs_info, is_dev_replace);
2858 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2859 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
2860 if (!dev || (dev->missing && !is_dev_replace)) {
2861 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2862 scrub_workers_put(fs_info);
2865 mutex_lock(&fs_info->scrub_lock);
2867 if (!dev->in_fs_metadata || dev->is_tgtdev_for_dev_replace) {
2868 mutex_unlock(&fs_info->scrub_lock);
2869 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2870 scrub_workers_put(fs_info);
2874 btrfs_dev_replace_lock(&fs_info->dev_replace);
2875 if (dev->scrub_device ||
2877 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
2878 btrfs_dev_replace_unlock(&fs_info->dev_replace);
2879 mutex_unlock(&fs_info->scrub_lock);
2880 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2881 scrub_workers_put(fs_info);
2882 return -EINPROGRESS;
2884 btrfs_dev_replace_unlock(&fs_info->dev_replace);
2885 sctx = scrub_setup_ctx(dev, is_dev_replace);
2887 mutex_unlock(&fs_info->scrub_lock);
2888 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2889 scrub_workers_put(fs_info);
2890 return PTR_ERR(sctx);
2892 sctx->readonly = readonly;
2893 dev->scrub_device = sctx;
2895 atomic_inc(&fs_info->scrubs_running);
2896 mutex_unlock(&fs_info->scrub_lock);
2897 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2899 if (!is_dev_replace) {
2900 down_read(&fs_info->scrub_super_lock);
2901 ret = scrub_supers(sctx, dev);
2902 up_read(&fs_info->scrub_super_lock);
2906 ret = scrub_enumerate_chunks(sctx, dev, start, end,
2909 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
2910 atomic_dec(&fs_info->scrubs_running);
2911 wake_up(&fs_info->scrub_pause_wait);
2913 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0);
2916 memcpy(progress, &sctx->stat, sizeof(*progress));
2918 mutex_lock(&fs_info->scrub_lock);
2919 dev->scrub_device = NULL;
2920 mutex_unlock(&fs_info->scrub_lock);
2922 scrub_free_ctx(sctx);
2923 scrub_workers_put(fs_info);
2928 void btrfs_scrub_pause(struct btrfs_root *root)
2930 struct btrfs_fs_info *fs_info = root->fs_info;
2932 mutex_lock(&fs_info->scrub_lock);
2933 atomic_inc(&fs_info->scrub_pause_req);
2934 while (atomic_read(&fs_info->scrubs_paused) !=
2935 atomic_read(&fs_info->scrubs_running)) {
2936 mutex_unlock(&fs_info->scrub_lock);
2937 wait_event(fs_info->scrub_pause_wait,
2938 atomic_read(&fs_info->scrubs_paused) ==
2939 atomic_read(&fs_info->scrubs_running));
2940 mutex_lock(&fs_info->scrub_lock);
2942 mutex_unlock(&fs_info->scrub_lock);
2945 void btrfs_scrub_continue(struct btrfs_root *root)
2947 struct btrfs_fs_info *fs_info = root->fs_info;
2949 atomic_dec(&fs_info->scrub_pause_req);
2950 wake_up(&fs_info->scrub_pause_wait);
2953 void btrfs_scrub_pause_super(struct btrfs_root *root)
2955 down_write(&root->fs_info->scrub_super_lock);
2958 void btrfs_scrub_continue_super(struct btrfs_root *root)
2960 up_write(&root->fs_info->scrub_super_lock);
2963 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
2965 mutex_lock(&fs_info->scrub_lock);
2966 if (!atomic_read(&fs_info->scrubs_running)) {
2967 mutex_unlock(&fs_info->scrub_lock);
2971 atomic_inc(&fs_info->scrub_cancel_req);
2972 while (atomic_read(&fs_info->scrubs_running)) {
2973 mutex_unlock(&fs_info->scrub_lock);
2974 wait_event(fs_info->scrub_pause_wait,
2975 atomic_read(&fs_info->scrubs_running) == 0);
2976 mutex_lock(&fs_info->scrub_lock);
2978 atomic_dec(&fs_info->scrub_cancel_req);
2979 mutex_unlock(&fs_info->scrub_lock);
2984 int btrfs_scrub_cancel_dev(struct btrfs_fs_info *fs_info,
2985 struct btrfs_device *dev)
2987 struct scrub_ctx *sctx;
2989 mutex_lock(&fs_info->scrub_lock);
2990 sctx = dev->scrub_device;
2992 mutex_unlock(&fs_info->scrub_lock);
2995 atomic_inc(&sctx->cancel_req);
2996 while (dev->scrub_device) {
2997 mutex_unlock(&fs_info->scrub_lock);
2998 wait_event(fs_info->scrub_pause_wait,
2999 dev->scrub_device == NULL);
3000 mutex_lock(&fs_info->scrub_lock);
3002 mutex_unlock(&fs_info->scrub_lock);
3007 int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid)
3009 struct btrfs_fs_info *fs_info = root->fs_info;
3010 struct btrfs_device *dev;
3014 * we have to hold the device_list_mutex here so the device
3015 * does not go away in cancel_dev. FIXME: find a better solution
3017 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3018 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
3020 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3023 ret = btrfs_scrub_cancel_dev(fs_info, dev);
3024 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3029 int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
3030 struct btrfs_scrub_progress *progress)
3032 struct btrfs_device *dev;
3033 struct scrub_ctx *sctx = NULL;
3035 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
3036 dev = btrfs_find_device(root->fs_info, devid, NULL, NULL);
3038 sctx = dev->scrub_device;
3040 memcpy(progress, &sctx->stat, sizeof(*progress));
3041 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3043 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
3046 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
3047 u64 extent_logical, u64 extent_len,
3048 u64 *extent_physical,
3049 struct btrfs_device **extent_dev,
3050 int *extent_mirror_num)
3053 struct btrfs_bio *bbio = NULL;
3056 mapped_length = extent_len;
3057 ret = btrfs_map_block(fs_info, READ, extent_logical,
3058 &mapped_length, &bbio, 0);
3059 if (ret || !bbio || mapped_length < extent_len ||
3060 !bbio->stripes[0].dev->bdev) {
3065 *extent_physical = bbio->stripes[0].physical;
3066 *extent_mirror_num = bbio->mirror_num;
3067 *extent_dev = bbio->stripes[0].dev;
3071 static int scrub_setup_wr_ctx(struct scrub_ctx *sctx,
3072 struct scrub_wr_ctx *wr_ctx,
3073 struct btrfs_fs_info *fs_info,
3074 struct btrfs_device *dev,
3077 WARN_ON(wr_ctx->wr_curr_bio != NULL);
3079 mutex_init(&wr_ctx->wr_lock);
3080 wr_ctx->wr_curr_bio = NULL;
3081 if (!is_dev_replace)
3084 WARN_ON(!dev->bdev);
3085 wr_ctx->pages_per_wr_bio = min_t(int, SCRUB_PAGES_PER_WR_BIO,
3086 bio_get_nr_vecs(dev->bdev));
3087 wr_ctx->tgtdev = dev;
3088 atomic_set(&wr_ctx->flush_all_writes, 0);
3092 static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx)
3094 mutex_lock(&wr_ctx->wr_lock);
3095 kfree(wr_ctx->wr_curr_bio);
3096 wr_ctx->wr_curr_bio = NULL;
3097 mutex_unlock(&wr_ctx->wr_lock);
3100 static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
3101 int mirror_num, u64 physical_for_dev_replace)
3103 struct scrub_copy_nocow_ctx *nocow_ctx;
3104 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
3106 nocow_ctx = kzalloc(sizeof(*nocow_ctx), GFP_NOFS);
3108 spin_lock(&sctx->stat_lock);
3109 sctx->stat.malloc_errors++;
3110 spin_unlock(&sctx->stat_lock);
3114 scrub_pending_trans_workers_inc(sctx);
3116 nocow_ctx->sctx = sctx;
3117 nocow_ctx->logical = logical;
3118 nocow_ctx->len = len;
3119 nocow_ctx->mirror_num = mirror_num;
3120 nocow_ctx->physical_for_dev_replace = physical_for_dev_replace;
3121 nocow_ctx->work.func = copy_nocow_pages_worker;
3122 btrfs_queue_worker(&fs_info->scrub_nocow_workers,
3128 static void copy_nocow_pages_worker(struct btrfs_work *work)
3130 struct scrub_copy_nocow_ctx *nocow_ctx =
3131 container_of(work, struct scrub_copy_nocow_ctx, work);
3132 struct scrub_ctx *sctx = nocow_ctx->sctx;
3133 u64 logical = nocow_ctx->logical;
3134 u64 len = nocow_ctx->len;
3135 int mirror_num = nocow_ctx->mirror_num;
3136 u64 physical_for_dev_replace = nocow_ctx->physical_for_dev_replace;
3138 struct btrfs_trans_handle *trans = NULL;
3139 struct btrfs_fs_info *fs_info;
3140 struct btrfs_path *path;
3141 struct btrfs_root *root;
3142 int not_written = 0;
3144 fs_info = sctx->dev_root->fs_info;
3145 root = fs_info->extent_root;
3147 path = btrfs_alloc_path();
3149 spin_lock(&sctx->stat_lock);
3150 sctx->stat.malloc_errors++;
3151 spin_unlock(&sctx->stat_lock);
3156 trans = btrfs_join_transaction(root);
3157 if (IS_ERR(trans)) {
3162 ret = iterate_inodes_from_logical(logical, fs_info, path,
3163 copy_nocow_pages_for_inode,
3165 if (ret != 0 && ret != -ENOENT) {
3166 pr_warn("iterate_inodes_from_logical() failed: log %llu, phys %llu, len %llu, mir %llu, ret %d\n",
3167 (unsigned long long)logical,
3168 (unsigned long long)physical_for_dev_replace,
3169 (unsigned long long)len,
3170 (unsigned long long)mirror_num, ret);
3176 if (trans && !IS_ERR(trans))
3177 btrfs_end_transaction(trans, root);
3179 btrfs_dev_replace_stats_inc(&fs_info->dev_replace.
3180 num_uncorrectable_read_errors);
3182 btrfs_free_path(path);
3185 scrub_pending_trans_workers_dec(sctx);
3188 static int copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root, void *ctx)
3190 unsigned long index;
3191 struct scrub_copy_nocow_ctx *nocow_ctx = ctx;
3193 struct btrfs_key key;
3194 struct inode *inode = NULL;
3195 struct btrfs_root *local_root;
3196 u64 physical_for_dev_replace;
3198 struct btrfs_fs_info *fs_info = nocow_ctx->sctx->dev_root->fs_info;
3201 key.objectid = root;
3202 key.type = BTRFS_ROOT_ITEM_KEY;
3203 key.offset = (u64)-1;
3205 srcu_index = srcu_read_lock(&fs_info->subvol_srcu);
3207 local_root = btrfs_read_fs_root_no_name(fs_info, &key);
3208 if (IS_ERR(local_root)) {
3209 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
3210 return PTR_ERR(local_root);
3213 key.type = BTRFS_INODE_ITEM_KEY;
3214 key.objectid = inum;
3216 inode = btrfs_iget(fs_info->sb, &key, local_root, NULL);
3217 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
3219 return PTR_ERR(inode);
3221 physical_for_dev_replace = nocow_ctx->physical_for_dev_replace;
3222 len = nocow_ctx->len;
3223 while (len >= PAGE_CACHE_SIZE) {
3224 struct page *page = NULL;
3227 index = offset >> PAGE_CACHE_SHIFT;
3229 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
3231 pr_err("find_or_create_page() failed\n");
3236 if (PageUptodate(page)) {
3237 if (PageDirty(page))
3240 ClearPageError(page);
3241 ret_sub = extent_read_full_page(&BTRFS_I(inode)->
3243 page, btrfs_get_extent,
3244 nocow_ctx->mirror_num);
3249 wait_on_page_locked(page);
3250 if (!PageUptodate(page)) {
3255 ret_sub = write_page_nocow(nocow_ctx->sctx,
3256 physical_for_dev_replace, page);
3267 offset += PAGE_CACHE_SIZE;
3268 physical_for_dev_replace += PAGE_CACHE_SIZE;
3269 len -= PAGE_CACHE_SIZE;
3277 static int write_page_nocow(struct scrub_ctx *sctx,
3278 u64 physical_for_dev_replace, struct page *page)
3281 struct btrfs_device *dev;
3283 DECLARE_COMPLETION_ONSTACK(compl);
3285 dev = sctx->wr_ctx.tgtdev;
3289 printk_ratelimited(KERN_WARNING
3290 "btrfs: scrub write_page_nocow(bdev == NULL) is unexpected!\n");
3293 bio = bio_alloc(GFP_NOFS, 1);
3295 spin_lock(&sctx->stat_lock);
3296 sctx->stat.malloc_errors++;
3297 spin_unlock(&sctx->stat_lock);
3300 bio->bi_private = &compl;
3301 bio->bi_end_io = scrub_complete_bio_end_io;
3303 bio->bi_sector = physical_for_dev_replace >> 9;
3304 bio->bi_bdev = dev->bdev;
3305 ret = bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
3306 if (ret != PAGE_CACHE_SIZE) {
3309 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS);
3312 btrfsic_submit_bio(WRITE_SYNC, bio);
3313 wait_for_completion(&compl);
3315 if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
3316 goto leave_with_eio;