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"
33 * This is only the first step towards a full-features scrub. It reads all
34 * extent and super block and verifies the checksums. In case a bad checksum
35 * is found or the extent cannot be read, good data will be written back if
38 * Future enhancements:
39 * - In case an unrepairable extent is encountered, track which files are
40 * affected and report them
41 * - track and record media errors, throw out bad devices
42 * - add a mode to also read unallocated space
49 * the following three values only influence the performance.
50 * The last one configures the number of parallel and outstanding I/O
51 * operations. The first two values configure an upper limit for the number
52 * of (dynamically allocated) pages that are added to a bio.
54 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */
55 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */
56 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */
59 * the following value times PAGE_SIZE needs to be large enough to match the
60 * largest node/leaf/sector size that shall be supported.
61 * Values larger than BTRFS_STRIPE_LEN are not supported.
63 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
66 struct scrub_block *sblock;
68 struct btrfs_device *dev;
69 u64 flags; /* extent flags */
73 u64 physical_for_dev_replace;
76 unsigned int mirror_num:8;
77 unsigned int have_csum:1;
78 unsigned int io_error:1;
80 u8 csum[BTRFS_CSUM_SIZE];
85 struct scrub_ctx *sctx;
86 struct btrfs_device *dev;
91 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO
92 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO];
94 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO];
98 struct btrfs_work work;
102 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK];
104 atomic_t outstanding_pages;
105 atomic_t ref_count; /* free mem on transition to zero */
106 struct scrub_ctx *sctx;
108 unsigned int header_error:1;
109 unsigned int checksum_error:1;
110 unsigned int no_io_error_seen:1;
111 unsigned int generation_error:1; /* also sets header_error */
115 struct scrub_wr_ctx {
116 struct scrub_bio *wr_curr_bio;
117 struct btrfs_device *tgtdev;
118 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */
119 atomic_t flush_all_writes;
120 struct mutex wr_lock;
124 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX];
125 struct btrfs_root *dev_root;
128 atomic_t bios_in_flight;
129 atomic_t workers_pending;
130 spinlock_t list_lock;
131 wait_queue_head_t list_wait;
133 struct list_head csum_list;
136 int pages_per_rd_bio;
142 struct scrub_wr_ctx wr_ctx;
147 struct btrfs_scrub_progress stat;
148 spinlock_t stat_lock;
151 struct scrub_fixup_nodatasum {
152 struct scrub_ctx *sctx;
153 struct btrfs_device *dev;
155 struct btrfs_root *root;
156 struct btrfs_work work;
160 struct scrub_copy_nocow_ctx {
161 struct scrub_ctx *sctx;
165 u64 physical_for_dev_replace;
166 struct btrfs_work work;
169 struct scrub_warning {
170 struct btrfs_path *path;
171 u64 extent_item_size;
177 struct btrfs_device *dev;
183 static void scrub_pending_bio_inc(struct scrub_ctx *sctx);
184 static void scrub_pending_bio_dec(struct scrub_ctx *sctx);
185 static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx);
186 static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx);
187 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
188 static int scrub_setup_recheck_block(struct scrub_ctx *sctx,
189 struct btrfs_fs_info *fs_info,
190 struct scrub_block *original_sblock,
191 u64 length, u64 logical,
192 struct scrub_block *sblocks_for_recheck);
193 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
194 struct scrub_block *sblock, int is_metadata,
195 int have_csum, u8 *csum, u64 generation,
197 static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
198 struct scrub_block *sblock,
199 int is_metadata, int have_csum,
200 const u8 *csum, u64 generation,
202 static void scrub_complete_bio_end_io(struct bio *bio, int err);
203 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
204 struct scrub_block *sblock_good,
206 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
207 struct scrub_block *sblock_good,
208 int page_num, int force_write);
209 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock);
210 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
212 static int scrub_checksum_data(struct scrub_block *sblock);
213 static int scrub_checksum_tree_block(struct scrub_block *sblock);
214 static int scrub_checksum_super(struct scrub_block *sblock);
215 static void scrub_block_get(struct scrub_block *sblock);
216 static void scrub_block_put(struct scrub_block *sblock);
217 static void scrub_page_get(struct scrub_page *spage);
218 static void scrub_page_put(struct scrub_page *spage);
219 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
220 struct scrub_page *spage);
221 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
222 u64 physical, struct btrfs_device *dev, u64 flags,
223 u64 gen, int mirror_num, u8 *csum, int force,
224 u64 physical_for_dev_replace);
225 static void scrub_bio_end_io(struct bio *bio, int err);
226 static void scrub_bio_end_io_worker(struct btrfs_work *work);
227 static void scrub_block_complete(struct scrub_block *sblock);
228 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
229 u64 extent_logical, u64 extent_len,
230 u64 *extent_physical,
231 struct btrfs_device **extent_dev,
232 int *extent_mirror_num);
233 static int scrub_setup_wr_ctx(struct scrub_ctx *sctx,
234 struct scrub_wr_ctx *wr_ctx,
235 struct btrfs_fs_info *fs_info,
236 struct btrfs_device *dev,
238 static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx);
239 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
240 struct scrub_page *spage);
241 static void scrub_wr_submit(struct scrub_ctx *sctx);
242 static void scrub_wr_bio_end_io(struct bio *bio, int err);
243 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work);
244 static int write_page_nocow(struct scrub_ctx *sctx,
245 u64 physical_for_dev_replace, struct page *page);
246 static int copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root,
248 static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
249 int mirror_num, u64 physical_for_dev_replace);
250 static void copy_nocow_pages_worker(struct btrfs_work *work);
253 static void scrub_pending_bio_inc(struct scrub_ctx *sctx)
255 atomic_inc(&sctx->bios_in_flight);
258 static void scrub_pending_bio_dec(struct scrub_ctx *sctx)
260 atomic_dec(&sctx->bios_in_flight);
261 wake_up(&sctx->list_wait);
265 * used for workers that require transaction commits (i.e., for the
268 static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx)
270 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
273 * increment scrubs_running to prevent cancel requests from
274 * completing as long as a worker is running. we must also
275 * increment scrubs_paused to prevent deadlocking on pause
276 * requests used for transactions commits (as the worker uses a
277 * transaction context). it is safe to regard the worker
278 * as paused for all matters practical. effectively, we only
279 * avoid cancellation requests from completing.
281 mutex_lock(&fs_info->scrub_lock);
282 atomic_inc(&fs_info->scrubs_running);
283 atomic_inc(&fs_info->scrubs_paused);
284 mutex_unlock(&fs_info->scrub_lock);
285 atomic_inc(&sctx->workers_pending);
288 /* used for workers that require transaction commits */
289 static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx)
291 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
294 * see scrub_pending_trans_workers_inc() why we're pretending
295 * to be paused in the scrub counters
297 mutex_lock(&fs_info->scrub_lock);
298 atomic_dec(&fs_info->scrubs_running);
299 atomic_dec(&fs_info->scrubs_paused);
300 mutex_unlock(&fs_info->scrub_lock);
301 atomic_dec(&sctx->workers_pending);
302 wake_up(&fs_info->scrub_pause_wait);
303 wake_up(&sctx->list_wait);
306 static void scrub_free_csums(struct scrub_ctx *sctx)
308 while (!list_empty(&sctx->csum_list)) {
309 struct btrfs_ordered_sum *sum;
310 sum = list_first_entry(&sctx->csum_list,
311 struct btrfs_ordered_sum, list);
312 list_del(&sum->list);
317 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx)
324 scrub_free_wr_ctx(&sctx->wr_ctx);
326 /* this can happen when scrub is cancelled */
327 if (sctx->curr != -1) {
328 struct scrub_bio *sbio = sctx->bios[sctx->curr];
330 for (i = 0; i < sbio->page_count; i++) {
331 WARN_ON(!sbio->pagev[i]->page);
332 scrub_block_put(sbio->pagev[i]->sblock);
337 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
338 struct scrub_bio *sbio = sctx->bios[i];
345 scrub_free_csums(sctx);
349 static noinline_for_stack
350 struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace)
352 struct scrub_ctx *sctx;
354 struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
355 int pages_per_rd_bio;
359 * the setting of pages_per_rd_bio is correct for scrub but might
360 * be wrong for the dev_replace code where we might read from
361 * different devices in the initial huge bios. However, that
362 * code is able to correctly handle the case when adding a page
366 pages_per_rd_bio = min_t(int, SCRUB_PAGES_PER_RD_BIO,
367 bio_get_nr_vecs(dev->bdev));
369 pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO;
370 sctx = kzalloc(sizeof(*sctx), GFP_NOFS);
373 sctx->is_dev_replace = is_dev_replace;
374 sctx->pages_per_rd_bio = pages_per_rd_bio;
376 sctx->dev_root = dev->dev_root;
377 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
378 struct scrub_bio *sbio;
380 sbio = kzalloc(sizeof(*sbio), GFP_NOFS);
383 sctx->bios[i] = sbio;
387 sbio->page_count = 0;
388 sbio->work.func = scrub_bio_end_io_worker;
390 if (i != SCRUB_BIOS_PER_SCTX - 1)
391 sctx->bios[i]->next_free = i + 1;
393 sctx->bios[i]->next_free = -1;
395 sctx->first_free = 0;
396 sctx->nodesize = dev->dev_root->nodesize;
397 sctx->leafsize = dev->dev_root->leafsize;
398 sctx->sectorsize = dev->dev_root->sectorsize;
399 atomic_set(&sctx->bios_in_flight, 0);
400 atomic_set(&sctx->workers_pending, 0);
401 atomic_set(&sctx->cancel_req, 0);
402 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
403 INIT_LIST_HEAD(&sctx->csum_list);
405 spin_lock_init(&sctx->list_lock);
406 spin_lock_init(&sctx->stat_lock);
407 init_waitqueue_head(&sctx->list_wait);
409 ret = scrub_setup_wr_ctx(sctx, &sctx->wr_ctx, fs_info,
410 fs_info->dev_replace.tgtdev, is_dev_replace);
412 scrub_free_ctx(sctx);
418 scrub_free_ctx(sctx);
419 return ERR_PTR(-ENOMEM);
422 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root,
429 struct extent_buffer *eb;
430 struct btrfs_inode_item *inode_item;
431 struct scrub_warning *swarn = warn_ctx;
432 struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info;
433 struct inode_fs_paths *ipath = NULL;
434 struct btrfs_root *local_root;
435 struct btrfs_key root_key;
437 root_key.objectid = root;
438 root_key.type = BTRFS_ROOT_ITEM_KEY;
439 root_key.offset = (u64)-1;
440 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
441 if (IS_ERR(local_root)) {
442 ret = PTR_ERR(local_root);
446 ret = inode_item_info(inum, 0, local_root, swarn->path);
448 btrfs_release_path(swarn->path);
452 eb = swarn->path->nodes[0];
453 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
454 struct btrfs_inode_item);
455 isize = btrfs_inode_size(eb, inode_item);
456 nlink = btrfs_inode_nlink(eb, inode_item);
457 btrfs_release_path(swarn->path);
459 ipath = init_ipath(4096, local_root, swarn->path);
461 ret = PTR_ERR(ipath);
465 ret = paths_from_inode(inum, ipath);
471 * we deliberately ignore the bit ipath might have been too small to
472 * hold all of the paths here
474 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
475 printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
476 "%s, sector %llu, root %llu, inode %llu, offset %llu, "
477 "length %llu, links %u (path: %s)\n", swarn->errstr,
478 swarn->logical, rcu_str_deref(swarn->dev->name),
479 (unsigned long long)swarn->sector, root, inum, offset,
480 min(isize - offset, (u64)PAGE_SIZE), nlink,
481 (char *)(unsigned long)ipath->fspath->val[i]);
487 printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
488 "%s, sector %llu, root %llu, inode %llu, offset %llu: path "
489 "resolving failed with ret=%d\n", swarn->errstr,
490 swarn->logical, rcu_str_deref(swarn->dev->name),
491 (unsigned long long)swarn->sector, root, inum, offset, ret);
497 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
499 struct btrfs_device *dev;
500 struct btrfs_fs_info *fs_info;
501 struct btrfs_path *path;
502 struct btrfs_key found_key;
503 struct extent_buffer *eb;
504 struct btrfs_extent_item *ei;
505 struct scrub_warning swarn;
506 unsigned long ptr = 0;
512 const int bufsize = 4096;
515 WARN_ON(sblock->page_count < 1);
516 dev = sblock->pagev[0]->dev;
517 fs_info = sblock->sctx->dev_root->fs_info;
519 path = btrfs_alloc_path();
521 swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS);
522 swarn.msg_buf = kmalloc(bufsize, GFP_NOFS);
523 swarn.sector = (sblock->pagev[0]->physical) >> 9;
524 swarn.logical = sblock->pagev[0]->logical;
525 swarn.errstr = errstr;
527 swarn.msg_bufsize = bufsize;
528 swarn.scratch_bufsize = bufsize;
530 if (!path || !swarn.scratch_buf || !swarn.msg_buf)
533 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key,
538 extent_item_pos = swarn.logical - found_key.objectid;
539 swarn.extent_item_size = found_key.offset;
542 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
543 item_size = btrfs_item_size_nr(eb, path->slots[0]);
544 btrfs_release_path(path);
546 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
548 ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
549 &ref_root, &ref_level);
550 printk_in_rcu(KERN_WARNING
551 "btrfs: %s at logical %llu on dev %s, "
552 "sector %llu: metadata %s (level %d) in tree "
553 "%llu\n", errstr, swarn.logical,
554 rcu_str_deref(dev->name),
555 (unsigned long long)swarn.sector,
556 ref_level ? "node" : "leaf",
557 ret < 0 ? -1 : ref_level,
558 ret < 0 ? -1 : ref_root);
563 iterate_extent_inodes(fs_info, found_key.objectid,
565 scrub_print_warning_inode, &swarn);
569 btrfs_free_path(path);
570 kfree(swarn.scratch_buf);
571 kfree(swarn.msg_buf);
574 static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *fixup_ctx)
576 struct page *page = NULL;
578 struct scrub_fixup_nodatasum *fixup = fixup_ctx;
581 struct btrfs_key key;
582 struct inode *inode = NULL;
583 struct btrfs_fs_info *fs_info;
584 u64 end = offset + PAGE_SIZE - 1;
585 struct btrfs_root *local_root;
589 key.type = BTRFS_ROOT_ITEM_KEY;
590 key.offset = (u64)-1;
592 fs_info = fixup->root->fs_info;
593 srcu_index = srcu_read_lock(&fs_info->subvol_srcu);
595 local_root = btrfs_read_fs_root_no_name(fs_info, &key);
596 if (IS_ERR(local_root)) {
597 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
598 return PTR_ERR(local_root);
601 key.type = BTRFS_INODE_ITEM_KEY;
604 inode = btrfs_iget(fs_info->sb, &key, local_root, NULL);
605 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
607 return PTR_ERR(inode);
609 index = offset >> PAGE_CACHE_SHIFT;
611 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
617 if (PageUptodate(page)) {
618 if (PageDirty(page)) {
620 * we need to write the data to the defect sector. the
621 * data that was in that sector is not in memory,
622 * because the page was modified. we must not write the
623 * modified page to that sector.
625 * TODO: what could be done here: wait for the delalloc
626 * runner to write out that page (might involve
627 * COW) and see whether the sector is still
628 * referenced afterwards.
630 * For the meantime, we'll treat this error
631 * incorrectable, although there is a chance that a
632 * later scrub will find the bad sector again and that
633 * there's no dirty page in memory, then.
638 fs_info = BTRFS_I(inode)->root->fs_info;
639 ret = repair_io_failure(fs_info, offset, PAGE_SIZE,
640 fixup->logical, page,
646 * we need to get good data first. the general readpage path
647 * will call repair_io_failure for us, we just have to make
648 * sure we read the bad mirror.
650 ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
651 EXTENT_DAMAGED, GFP_NOFS);
653 /* set_extent_bits should give proper error */
660 ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
663 wait_on_page_locked(page);
665 corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset,
666 end, EXTENT_DAMAGED, 0, NULL);
668 clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
669 EXTENT_DAMAGED, GFP_NOFS);
681 if (ret == 0 && corrected) {
683 * we only need to call readpage for one of the inodes belonging
684 * to this extent. so make iterate_extent_inodes stop
692 static void scrub_fixup_nodatasum(struct btrfs_work *work)
695 struct scrub_fixup_nodatasum *fixup;
696 struct scrub_ctx *sctx;
697 struct btrfs_trans_handle *trans = NULL;
698 struct btrfs_fs_info *fs_info;
699 struct btrfs_path *path;
700 int uncorrectable = 0;
702 fixup = container_of(work, struct scrub_fixup_nodatasum, work);
704 fs_info = fixup->root->fs_info;
706 path = btrfs_alloc_path();
708 spin_lock(&sctx->stat_lock);
709 ++sctx->stat.malloc_errors;
710 spin_unlock(&sctx->stat_lock);
715 trans = btrfs_join_transaction(fixup->root);
722 * the idea is to trigger a regular read through the standard path. we
723 * read a page from the (failed) logical address by specifying the
724 * corresponding copynum of the failed sector. thus, that readpage is
726 * that is the point where on-the-fly error correction will kick in
727 * (once it's finished) and rewrite the failed sector if a good copy
730 ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info,
731 path, scrub_fixup_readpage,
739 spin_lock(&sctx->stat_lock);
740 ++sctx->stat.corrected_errors;
741 spin_unlock(&sctx->stat_lock);
744 if (trans && !IS_ERR(trans))
745 btrfs_end_transaction(trans, fixup->root);
747 spin_lock(&sctx->stat_lock);
748 ++sctx->stat.uncorrectable_errors;
749 spin_unlock(&sctx->stat_lock);
750 btrfs_dev_replace_stats_inc(
751 &sctx->dev_root->fs_info->dev_replace.
752 num_uncorrectable_read_errors);
753 printk_ratelimited_in_rcu(KERN_ERR
754 "btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
755 (unsigned long long)fixup->logical,
756 rcu_str_deref(fixup->dev->name));
759 btrfs_free_path(path);
762 scrub_pending_trans_workers_dec(sctx);
766 * scrub_handle_errored_block gets called when either verification of the
767 * pages failed or the bio failed to read, e.g. with EIO. In the latter
768 * case, this function handles all pages in the bio, even though only one
770 * The goal of this function is to repair the errored block by using the
771 * contents of one of the mirrors.
773 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
775 struct scrub_ctx *sctx = sblock_to_check->sctx;
776 struct btrfs_device *dev;
777 struct btrfs_fs_info *fs_info;
781 unsigned int failed_mirror_index;
782 unsigned int is_metadata;
783 unsigned int have_csum;
785 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
786 struct scrub_block *sblock_bad;
791 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
792 DEFAULT_RATELIMIT_BURST);
794 BUG_ON(sblock_to_check->page_count < 1);
795 fs_info = sctx->dev_root->fs_info;
796 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) {
798 * if we find an error in a super block, we just report it.
799 * They will get written with the next transaction commit
802 spin_lock(&sctx->stat_lock);
803 ++sctx->stat.super_errors;
804 spin_unlock(&sctx->stat_lock);
807 length = sblock_to_check->page_count * PAGE_SIZE;
808 logical = sblock_to_check->pagev[0]->logical;
809 generation = sblock_to_check->pagev[0]->generation;
810 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1);
811 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1;
812 is_metadata = !(sblock_to_check->pagev[0]->flags &
813 BTRFS_EXTENT_FLAG_DATA);
814 have_csum = sblock_to_check->pagev[0]->have_csum;
815 csum = sblock_to_check->pagev[0]->csum;
816 dev = sblock_to_check->pagev[0]->dev;
818 if (sctx->is_dev_replace && !is_metadata && !have_csum) {
819 sblocks_for_recheck = NULL;
824 * read all mirrors one after the other. This includes to
825 * re-read the extent or metadata block that failed (that was
826 * the cause that this fixup code is called) another time,
827 * page by page this time in order to know which pages
828 * caused I/O errors and which ones are good (for all mirrors).
829 * It is the goal to handle the situation when more than one
830 * mirror contains I/O errors, but the errors do not
831 * overlap, i.e. the data can be repaired by selecting the
832 * pages from those mirrors without I/O error on the
833 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
834 * would be that mirror #1 has an I/O error on the first page,
835 * the second page is good, and mirror #2 has an I/O error on
836 * the second page, but the first page is good.
837 * Then the first page of the first mirror can be repaired by
838 * taking the first page of the second mirror, and the
839 * second page of the second mirror can be repaired by
840 * copying the contents of the 2nd page of the 1st mirror.
841 * One more note: if the pages of one mirror contain I/O
842 * errors, the checksum cannot be verified. In order to get
843 * the best data for repairing, the first attempt is to find
844 * a mirror without I/O errors and with a validated checksum.
845 * Only if this is not possible, the pages are picked from
846 * mirrors with I/O errors without considering the checksum.
847 * If the latter is the case, at the end, the checksum of the
848 * repaired area is verified in order to correctly maintain
852 sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS *
853 sizeof(*sblocks_for_recheck),
855 if (!sblocks_for_recheck) {
856 spin_lock(&sctx->stat_lock);
857 sctx->stat.malloc_errors++;
858 sctx->stat.read_errors++;
859 sctx->stat.uncorrectable_errors++;
860 spin_unlock(&sctx->stat_lock);
861 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
865 /* setup the context, map the logical blocks and alloc the pages */
866 ret = scrub_setup_recheck_block(sctx, fs_info, sblock_to_check, length,
867 logical, sblocks_for_recheck);
869 spin_lock(&sctx->stat_lock);
870 sctx->stat.read_errors++;
871 sctx->stat.uncorrectable_errors++;
872 spin_unlock(&sctx->stat_lock);
873 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
876 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
877 sblock_bad = sblocks_for_recheck + failed_mirror_index;
879 /* build and submit the bios for the failed mirror, check checksums */
880 scrub_recheck_block(fs_info, sblock_bad, is_metadata, have_csum,
881 csum, generation, sctx->csum_size);
883 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
884 sblock_bad->no_io_error_seen) {
886 * the error disappeared after reading page by page, or
887 * the area was part of a huge bio and other parts of the
888 * bio caused I/O errors, or the block layer merged several
889 * read requests into one and the error is caused by a
890 * different bio (usually one of the two latter cases is
893 spin_lock(&sctx->stat_lock);
894 sctx->stat.unverified_errors++;
895 spin_unlock(&sctx->stat_lock);
897 if (sctx->is_dev_replace)
898 scrub_write_block_to_dev_replace(sblock_bad);
902 if (!sblock_bad->no_io_error_seen) {
903 spin_lock(&sctx->stat_lock);
904 sctx->stat.read_errors++;
905 spin_unlock(&sctx->stat_lock);
906 if (__ratelimit(&_rs))
907 scrub_print_warning("i/o error", sblock_to_check);
908 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS);
909 } else if (sblock_bad->checksum_error) {
910 spin_lock(&sctx->stat_lock);
911 sctx->stat.csum_errors++;
912 spin_unlock(&sctx->stat_lock);
913 if (__ratelimit(&_rs))
914 scrub_print_warning("checksum error", sblock_to_check);
915 btrfs_dev_stat_inc_and_print(dev,
916 BTRFS_DEV_STAT_CORRUPTION_ERRS);
917 } else if (sblock_bad->header_error) {
918 spin_lock(&sctx->stat_lock);
919 sctx->stat.verify_errors++;
920 spin_unlock(&sctx->stat_lock);
921 if (__ratelimit(&_rs))
922 scrub_print_warning("checksum/header error",
924 if (sblock_bad->generation_error)
925 btrfs_dev_stat_inc_and_print(dev,
926 BTRFS_DEV_STAT_GENERATION_ERRS);
928 btrfs_dev_stat_inc_and_print(dev,
929 BTRFS_DEV_STAT_CORRUPTION_ERRS);
932 if (sctx->readonly && !sctx->is_dev_replace)
933 goto did_not_correct_error;
935 if (!is_metadata && !have_csum) {
936 struct scrub_fixup_nodatasum *fixup_nodatasum;
939 WARN_ON(sctx->is_dev_replace);
942 * !is_metadata and !have_csum, this means that the data
943 * might not be COW'ed, that it might be modified
944 * concurrently. The general strategy to work on the
945 * commit root does not help in the case when COW is not
948 fixup_nodatasum = kzalloc(sizeof(*fixup_nodatasum), GFP_NOFS);
949 if (!fixup_nodatasum)
950 goto did_not_correct_error;
951 fixup_nodatasum->sctx = sctx;
952 fixup_nodatasum->dev = dev;
953 fixup_nodatasum->logical = logical;
954 fixup_nodatasum->root = fs_info->extent_root;
955 fixup_nodatasum->mirror_num = failed_mirror_index + 1;
956 scrub_pending_trans_workers_inc(sctx);
957 fixup_nodatasum->work.func = scrub_fixup_nodatasum;
958 btrfs_queue_worker(&fs_info->scrub_workers,
959 &fixup_nodatasum->work);
964 * now build and submit the bios for the other mirrors, check
966 * First try to pick the mirror which is completely without I/O
967 * errors and also does not have a checksum error.
968 * If one is found, and if a checksum is present, the full block
969 * that is known to contain an error is rewritten. Afterwards
970 * the block is known to be corrected.
971 * If a mirror is found which is completely correct, and no
972 * checksum is present, only those pages are rewritten that had
973 * an I/O error in the block to be repaired, since it cannot be
974 * determined, which copy of the other pages is better (and it
975 * could happen otherwise that a correct page would be
976 * overwritten by a bad one).
978 for (mirror_index = 0;
979 mirror_index < BTRFS_MAX_MIRRORS &&
980 sblocks_for_recheck[mirror_index].page_count > 0;
982 struct scrub_block *sblock_other;
984 if (mirror_index == failed_mirror_index)
986 sblock_other = sblocks_for_recheck + mirror_index;
988 /* build and submit the bios, check checksums */
989 scrub_recheck_block(fs_info, sblock_other, is_metadata,
990 have_csum, csum, generation,
993 if (!sblock_other->header_error &&
994 !sblock_other->checksum_error &&
995 sblock_other->no_io_error_seen) {
996 if (sctx->is_dev_replace) {
997 scrub_write_block_to_dev_replace(sblock_other);
999 int force_write = is_metadata || have_csum;
1001 ret = scrub_repair_block_from_good_copy(
1002 sblock_bad, sblock_other,
1006 goto corrected_error;
1011 * for dev_replace, pick good pages and write to the target device.
1013 if (sctx->is_dev_replace) {
1015 for (page_num = 0; page_num < sblock_bad->page_count;
1020 for (mirror_index = 0;
1021 mirror_index < BTRFS_MAX_MIRRORS &&
1022 sblocks_for_recheck[mirror_index].page_count > 0;
1024 struct scrub_block *sblock_other =
1025 sblocks_for_recheck + mirror_index;
1026 struct scrub_page *page_other =
1027 sblock_other->pagev[page_num];
1029 if (!page_other->io_error) {
1030 ret = scrub_write_page_to_dev_replace(
1031 sblock_other, page_num);
1033 /* succeeded for this page */
1037 btrfs_dev_replace_stats_inc(
1039 fs_info->dev_replace.
1047 * did not find a mirror to fetch the page
1048 * from. scrub_write_page_to_dev_replace()
1049 * handles this case (page->io_error), by
1050 * filling the block with zeros before
1051 * submitting the write request
1054 ret = scrub_write_page_to_dev_replace(
1055 sblock_bad, page_num);
1057 btrfs_dev_replace_stats_inc(
1058 &sctx->dev_root->fs_info->
1059 dev_replace.num_write_errors);
1067 * for regular scrub, repair those pages that are errored.
1068 * In case of I/O errors in the area that is supposed to be
1069 * repaired, continue by picking good copies of those pages.
1070 * Select the good pages from mirrors to rewrite bad pages from
1071 * the area to fix. Afterwards verify the checksum of the block
1072 * that is supposed to be repaired. This verification step is
1073 * only done for the purpose of statistic counting and for the
1074 * final scrub report, whether errors remain.
1075 * A perfect algorithm could make use of the checksum and try
1076 * all possible combinations of pages from the different mirrors
1077 * until the checksum verification succeeds. For example, when
1078 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
1079 * of mirror #2 is readable but the final checksum test fails,
1080 * then the 2nd page of mirror #3 could be tried, whether now
1081 * the final checksum succeedes. But this would be a rare
1082 * exception and is therefore not implemented. At least it is
1083 * avoided that the good copy is overwritten.
1084 * A more useful improvement would be to pick the sectors
1085 * without I/O error based on sector sizes (512 bytes on legacy
1086 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
1087 * mirror could be repaired by taking 512 byte of a different
1088 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
1089 * area are unreadable.
1092 /* can only fix I/O errors from here on */
1093 if (sblock_bad->no_io_error_seen)
1094 goto did_not_correct_error;
1097 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1098 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1100 if (!page_bad->io_error)
1103 for (mirror_index = 0;
1104 mirror_index < BTRFS_MAX_MIRRORS &&
1105 sblocks_for_recheck[mirror_index].page_count > 0;
1107 struct scrub_block *sblock_other = sblocks_for_recheck +
1109 struct scrub_page *page_other = sblock_other->pagev[
1112 if (!page_other->io_error) {
1113 ret = scrub_repair_page_from_good_copy(
1114 sblock_bad, sblock_other, page_num, 0);
1116 page_bad->io_error = 0;
1117 break; /* succeeded for this page */
1122 if (page_bad->io_error) {
1123 /* did not find a mirror to copy the page from */
1129 if (is_metadata || have_csum) {
1131 * need to verify the checksum now that all
1132 * sectors on disk are repaired (the write
1133 * request for data to be repaired is on its way).
1134 * Just be lazy and use scrub_recheck_block()
1135 * which re-reads the data before the checksum
1136 * is verified, but most likely the data comes out
1137 * of the page cache.
1139 scrub_recheck_block(fs_info, sblock_bad,
1140 is_metadata, have_csum, csum,
1141 generation, sctx->csum_size);
1142 if (!sblock_bad->header_error &&
1143 !sblock_bad->checksum_error &&
1144 sblock_bad->no_io_error_seen)
1145 goto corrected_error;
1147 goto did_not_correct_error;
1150 spin_lock(&sctx->stat_lock);
1151 sctx->stat.corrected_errors++;
1152 spin_unlock(&sctx->stat_lock);
1153 printk_ratelimited_in_rcu(KERN_ERR
1154 "btrfs: fixed up error at logical %llu on dev %s\n",
1155 (unsigned long long)logical,
1156 rcu_str_deref(dev->name));
1159 did_not_correct_error:
1160 spin_lock(&sctx->stat_lock);
1161 sctx->stat.uncorrectable_errors++;
1162 spin_unlock(&sctx->stat_lock);
1163 printk_ratelimited_in_rcu(KERN_ERR
1164 "btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
1165 (unsigned long long)logical,
1166 rcu_str_deref(dev->name));
1170 if (sblocks_for_recheck) {
1171 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
1173 struct scrub_block *sblock = sblocks_for_recheck +
1177 for (page_index = 0; page_index < sblock->page_count;
1179 sblock->pagev[page_index]->sblock = NULL;
1180 scrub_page_put(sblock->pagev[page_index]);
1183 kfree(sblocks_for_recheck);
1189 static int scrub_setup_recheck_block(struct scrub_ctx *sctx,
1190 struct btrfs_fs_info *fs_info,
1191 struct scrub_block *original_sblock,
1192 u64 length, u64 logical,
1193 struct scrub_block *sblocks_for_recheck)
1200 * note: the two members ref_count and outstanding_pages
1201 * are not used (and not set) in the blocks that are used for
1202 * the recheck procedure
1206 while (length > 0) {
1207 u64 sublen = min_t(u64, length, PAGE_SIZE);
1208 u64 mapped_length = sublen;
1209 struct btrfs_bio *bbio = NULL;
1212 * with a length of PAGE_SIZE, each returned stripe
1213 * represents one mirror
1215 ret = btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, logical,
1216 &mapped_length, &bbio, 0);
1217 if (ret || !bbio || mapped_length < sublen) {
1222 BUG_ON(page_index >= SCRUB_PAGES_PER_RD_BIO);
1223 for (mirror_index = 0; mirror_index < (int)bbio->num_stripes;
1225 struct scrub_block *sblock;
1226 struct scrub_page *page;
1228 if (mirror_index >= BTRFS_MAX_MIRRORS)
1231 sblock = sblocks_for_recheck + mirror_index;
1232 sblock->sctx = sctx;
1233 page = kzalloc(sizeof(*page), GFP_NOFS);
1236 spin_lock(&sctx->stat_lock);
1237 sctx->stat.malloc_errors++;
1238 spin_unlock(&sctx->stat_lock);
1242 scrub_page_get(page);
1243 sblock->pagev[page_index] = page;
1244 page->logical = logical;
1245 page->physical = bbio->stripes[mirror_index].physical;
1246 BUG_ON(page_index >= original_sblock->page_count);
1247 page->physical_for_dev_replace =
1248 original_sblock->pagev[page_index]->
1249 physical_for_dev_replace;
1250 /* for missing devices, dev->bdev is NULL */
1251 page->dev = bbio->stripes[mirror_index].dev;
1252 page->mirror_num = mirror_index + 1;
1253 sblock->page_count++;
1254 page->page = alloc_page(GFP_NOFS);
1268 * this function will check the on disk data for checksum errors, header
1269 * errors and read I/O errors. If any I/O errors happen, the exact pages
1270 * which are errored are marked as being bad. The goal is to enable scrub
1271 * to take those pages that are not errored from all the mirrors so that
1272 * the pages that are errored in the just handled mirror can be repaired.
1274 static void scrub_recheck_block(struct btrfs_fs_info *fs_info,
1275 struct scrub_block *sblock, int is_metadata,
1276 int have_csum, u8 *csum, u64 generation,
1281 sblock->no_io_error_seen = 1;
1282 sblock->header_error = 0;
1283 sblock->checksum_error = 0;
1285 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1287 struct scrub_page *page = sblock->pagev[page_num];
1288 DECLARE_COMPLETION_ONSTACK(complete);
1290 if (page->dev->bdev == NULL) {
1292 sblock->no_io_error_seen = 0;
1296 WARN_ON(!page->page);
1297 bio = bio_alloc(GFP_NOFS, 1);
1300 sblock->no_io_error_seen = 0;
1303 bio->bi_bdev = page->dev->bdev;
1304 bio->bi_sector = page->physical >> 9;
1305 bio->bi_end_io = scrub_complete_bio_end_io;
1306 bio->bi_private = &complete;
1308 bio_add_page(bio, page->page, PAGE_SIZE, 0);
1309 btrfsic_submit_bio(READ, bio);
1311 /* this will also unplug the queue */
1312 wait_for_completion(&complete);
1314 page->io_error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
1315 if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
1316 sblock->no_io_error_seen = 0;
1320 if (sblock->no_io_error_seen)
1321 scrub_recheck_block_checksum(fs_info, sblock, is_metadata,
1322 have_csum, csum, generation,
1328 static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
1329 struct scrub_block *sblock,
1330 int is_metadata, int have_csum,
1331 const u8 *csum, u64 generation,
1335 u8 calculated_csum[BTRFS_CSUM_SIZE];
1337 struct btrfs_root *root = fs_info->extent_root;
1338 void *mapped_buffer;
1340 WARN_ON(!sblock->pagev[0]->page);
1342 struct btrfs_header *h;
1344 mapped_buffer = kmap_atomic(sblock->pagev[0]->page);
1345 h = (struct btrfs_header *)mapped_buffer;
1347 if (sblock->pagev[0]->logical != le64_to_cpu(h->bytenr) ||
1348 memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE) ||
1349 memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1351 sblock->header_error = 1;
1352 } else if (generation != le64_to_cpu(h->generation)) {
1353 sblock->header_error = 1;
1354 sblock->generation_error = 1;
1361 mapped_buffer = kmap_atomic(sblock->pagev[0]->page);
1364 for (page_num = 0;;) {
1365 if (page_num == 0 && is_metadata)
1366 crc = btrfs_csum_data(root,
1367 ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE,
1368 crc, PAGE_SIZE - BTRFS_CSUM_SIZE);
1370 crc = btrfs_csum_data(root, mapped_buffer, crc,
1373 kunmap_atomic(mapped_buffer);
1375 if (page_num >= sblock->page_count)
1377 WARN_ON(!sblock->pagev[page_num]->page);
1379 mapped_buffer = kmap_atomic(sblock->pagev[page_num]->page);
1382 btrfs_csum_final(crc, calculated_csum);
1383 if (memcmp(calculated_csum, csum, csum_size))
1384 sblock->checksum_error = 1;
1387 static void scrub_complete_bio_end_io(struct bio *bio, int err)
1389 complete((struct completion *)bio->bi_private);
1392 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1393 struct scrub_block *sblock_good,
1399 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1402 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1413 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1414 struct scrub_block *sblock_good,
1415 int page_num, int force_write)
1417 struct scrub_page *page_bad = sblock_bad->pagev[page_num];
1418 struct scrub_page *page_good = sblock_good->pagev[page_num];
1420 BUG_ON(page_bad->page == NULL);
1421 BUG_ON(page_good->page == NULL);
1422 if (force_write || sblock_bad->header_error ||
1423 sblock_bad->checksum_error || page_bad->io_error) {
1426 DECLARE_COMPLETION_ONSTACK(complete);
1428 if (!page_bad->dev->bdev) {
1429 printk_ratelimited(KERN_WARNING
1430 "btrfs: scrub_repair_page_from_good_copy(bdev == NULL) is unexpected!\n");
1434 bio = bio_alloc(GFP_NOFS, 1);
1437 bio->bi_bdev = page_bad->dev->bdev;
1438 bio->bi_sector = page_bad->physical >> 9;
1439 bio->bi_end_io = scrub_complete_bio_end_io;
1440 bio->bi_private = &complete;
1442 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1443 if (PAGE_SIZE != ret) {
1447 btrfsic_submit_bio(WRITE, bio);
1449 /* this will also unplug the queue */
1450 wait_for_completion(&complete);
1451 if (!bio_flagged(bio, BIO_UPTODATE)) {
1452 btrfs_dev_stat_inc_and_print(page_bad->dev,
1453 BTRFS_DEV_STAT_WRITE_ERRS);
1454 btrfs_dev_replace_stats_inc(
1455 &sblock_bad->sctx->dev_root->fs_info->
1456 dev_replace.num_write_errors);
1466 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock)
1470 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1473 ret = scrub_write_page_to_dev_replace(sblock, page_num);
1475 btrfs_dev_replace_stats_inc(
1476 &sblock->sctx->dev_root->fs_info->dev_replace.
1481 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock,
1484 struct scrub_page *spage = sblock->pagev[page_num];
1486 BUG_ON(spage->page == NULL);
1487 if (spage->io_error) {
1488 void *mapped_buffer = kmap_atomic(spage->page);
1490 memset(mapped_buffer, 0, PAGE_CACHE_SIZE);
1491 flush_dcache_page(spage->page);
1492 kunmap_atomic(mapped_buffer);
1494 return scrub_add_page_to_wr_bio(sblock->sctx, spage);
1497 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx,
1498 struct scrub_page *spage)
1500 struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx;
1501 struct scrub_bio *sbio;
1504 mutex_lock(&wr_ctx->wr_lock);
1506 if (!wr_ctx->wr_curr_bio) {
1507 wr_ctx->wr_curr_bio = kzalloc(sizeof(*wr_ctx->wr_curr_bio),
1509 if (!wr_ctx->wr_curr_bio) {
1510 mutex_unlock(&wr_ctx->wr_lock);
1513 wr_ctx->wr_curr_bio->sctx = sctx;
1514 wr_ctx->wr_curr_bio->page_count = 0;
1516 sbio = wr_ctx->wr_curr_bio;
1517 if (sbio->page_count == 0) {
1520 sbio->physical = spage->physical_for_dev_replace;
1521 sbio->logical = spage->logical;
1522 sbio->dev = wr_ctx->tgtdev;
1525 bio = bio_alloc(GFP_NOFS, wr_ctx->pages_per_wr_bio);
1527 mutex_unlock(&wr_ctx->wr_lock);
1533 bio->bi_private = sbio;
1534 bio->bi_end_io = scrub_wr_bio_end_io;
1535 bio->bi_bdev = sbio->dev->bdev;
1536 bio->bi_sector = sbio->physical >> 9;
1538 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1539 spage->physical_for_dev_replace ||
1540 sbio->logical + sbio->page_count * PAGE_SIZE !=
1542 scrub_wr_submit(sctx);
1546 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1547 if (ret != PAGE_SIZE) {
1548 if (sbio->page_count < 1) {
1551 mutex_unlock(&wr_ctx->wr_lock);
1554 scrub_wr_submit(sctx);
1558 sbio->pagev[sbio->page_count] = spage;
1559 scrub_page_get(spage);
1561 if (sbio->page_count == wr_ctx->pages_per_wr_bio)
1562 scrub_wr_submit(sctx);
1563 mutex_unlock(&wr_ctx->wr_lock);
1568 static void scrub_wr_submit(struct scrub_ctx *sctx)
1570 struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx;
1571 struct scrub_bio *sbio;
1573 if (!wr_ctx->wr_curr_bio)
1576 sbio = wr_ctx->wr_curr_bio;
1577 wr_ctx->wr_curr_bio = NULL;
1578 WARN_ON(!sbio->bio->bi_bdev);
1579 scrub_pending_bio_inc(sctx);
1580 /* process all writes in a single worker thread. Then the block layer
1581 * orders the requests before sending them to the driver which
1582 * doubled the write performance on spinning disks when measured
1584 btrfsic_submit_bio(WRITE, sbio->bio);
1587 static void scrub_wr_bio_end_io(struct bio *bio, int err)
1589 struct scrub_bio *sbio = bio->bi_private;
1590 struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info;
1595 sbio->work.func = scrub_wr_bio_end_io_worker;
1596 btrfs_queue_worker(&fs_info->scrub_wr_completion_workers, &sbio->work);
1599 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work)
1601 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1602 struct scrub_ctx *sctx = sbio->sctx;
1605 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO);
1607 struct btrfs_dev_replace *dev_replace =
1608 &sbio->sctx->dev_root->fs_info->dev_replace;
1610 for (i = 0; i < sbio->page_count; i++) {
1611 struct scrub_page *spage = sbio->pagev[i];
1613 spage->io_error = 1;
1614 btrfs_dev_replace_stats_inc(&dev_replace->
1619 for (i = 0; i < sbio->page_count; i++)
1620 scrub_page_put(sbio->pagev[i]);
1624 scrub_pending_bio_dec(sctx);
1627 static int scrub_checksum(struct scrub_block *sblock)
1632 WARN_ON(sblock->page_count < 1);
1633 flags = sblock->pagev[0]->flags;
1635 if (flags & BTRFS_EXTENT_FLAG_DATA)
1636 ret = scrub_checksum_data(sblock);
1637 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1638 ret = scrub_checksum_tree_block(sblock);
1639 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1640 (void)scrub_checksum_super(sblock);
1644 scrub_handle_errored_block(sblock);
1649 static int scrub_checksum_data(struct scrub_block *sblock)
1651 struct scrub_ctx *sctx = sblock->sctx;
1652 u8 csum[BTRFS_CSUM_SIZE];
1658 struct btrfs_root *root = sctx->dev_root;
1662 BUG_ON(sblock->page_count < 1);
1663 if (!sblock->pagev[0]->have_csum)
1666 on_disk_csum = sblock->pagev[0]->csum;
1667 page = sblock->pagev[0]->page;
1668 buffer = kmap_atomic(page);
1670 len = sctx->sectorsize;
1673 u64 l = min_t(u64, len, PAGE_SIZE);
1675 crc = btrfs_csum_data(root, buffer, crc, l);
1676 kunmap_atomic(buffer);
1681 BUG_ON(index >= sblock->page_count);
1682 BUG_ON(!sblock->pagev[index]->page);
1683 page = sblock->pagev[index]->page;
1684 buffer = kmap_atomic(page);
1687 btrfs_csum_final(crc, csum);
1688 if (memcmp(csum, on_disk_csum, sctx->csum_size))
1694 static int scrub_checksum_tree_block(struct scrub_block *sblock)
1696 struct scrub_ctx *sctx = sblock->sctx;
1697 struct btrfs_header *h;
1698 struct btrfs_root *root = sctx->dev_root;
1699 struct btrfs_fs_info *fs_info = root->fs_info;
1700 u8 calculated_csum[BTRFS_CSUM_SIZE];
1701 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1703 void *mapped_buffer;
1712 BUG_ON(sblock->page_count < 1);
1713 page = sblock->pagev[0]->page;
1714 mapped_buffer = kmap_atomic(page);
1715 h = (struct btrfs_header *)mapped_buffer;
1716 memcpy(on_disk_csum, h->csum, sctx->csum_size);
1719 * we don't use the getter functions here, as we
1720 * a) don't have an extent buffer and
1721 * b) the page is already kmapped
1724 if (sblock->pagev[0]->logical != le64_to_cpu(h->bytenr))
1727 if (sblock->pagev[0]->generation != le64_to_cpu(h->generation))
1730 if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1733 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1737 WARN_ON(sctx->nodesize != sctx->leafsize);
1738 len = sctx->nodesize - BTRFS_CSUM_SIZE;
1739 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1740 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1743 u64 l = min_t(u64, len, mapped_size);
1745 crc = btrfs_csum_data(root, p, crc, l);
1746 kunmap_atomic(mapped_buffer);
1751 BUG_ON(index >= sblock->page_count);
1752 BUG_ON(!sblock->pagev[index]->page);
1753 page = sblock->pagev[index]->page;
1754 mapped_buffer = kmap_atomic(page);
1755 mapped_size = PAGE_SIZE;
1759 btrfs_csum_final(crc, calculated_csum);
1760 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1763 return fail || crc_fail;
1766 static int scrub_checksum_super(struct scrub_block *sblock)
1768 struct btrfs_super_block *s;
1769 struct scrub_ctx *sctx = sblock->sctx;
1770 struct btrfs_root *root = sctx->dev_root;
1771 struct btrfs_fs_info *fs_info = root->fs_info;
1772 u8 calculated_csum[BTRFS_CSUM_SIZE];
1773 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1775 void *mapped_buffer;
1784 BUG_ON(sblock->page_count < 1);
1785 page = sblock->pagev[0]->page;
1786 mapped_buffer = kmap_atomic(page);
1787 s = (struct btrfs_super_block *)mapped_buffer;
1788 memcpy(on_disk_csum, s->csum, sctx->csum_size);
1790 if (sblock->pagev[0]->logical != le64_to_cpu(s->bytenr))
1793 if (sblock->pagev[0]->generation != le64_to_cpu(s->generation))
1796 if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1799 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1800 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1801 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1804 u64 l = min_t(u64, len, mapped_size);
1806 crc = btrfs_csum_data(root, p, crc, l);
1807 kunmap_atomic(mapped_buffer);
1812 BUG_ON(index >= sblock->page_count);
1813 BUG_ON(!sblock->pagev[index]->page);
1814 page = sblock->pagev[index]->page;
1815 mapped_buffer = kmap_atomic(page);
1816 mapped_size = PAGE_SIZE;
1820 btrfs_csum_final(crc, calculated_csum);
1821 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size))
1824 if (fail_cor + fail_gen) {
1826 * if we find an error in a super block, we just report it.
1827 * They will get written with the next transaction commit
1830 spin_lock(&sctx->stat_lock);
1831 ++sctx->stat.super_errors;
1832 spin_unlock(&sctx->stat_lock);
1834 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1835 BTRFS_DEV_STAT_CORRUPTION_ERRS);
1837 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev,
1838 BTRFS_DEV_STAT_GENERATION_ERRS);
1841 return fail_cor + fail_gen;
1844 static void scrub_block_get(struct scrub_block *sblock)
1846 atomic_inc(&sblock->ref_count);
1849 static void scrub_block_put(struct scrub_block *sblock)
1851 if (atomic_dec_and_test(&sblock->ref_count)) {
1854 for (i = 0; i < sblock->page_count; i++)
1855 scrub_page_put(sblock->pagev[i]);
1860 static void scrub_page_get(struct scrub_page *spage)
1862 atomic_inc(&spage->ref_count);
1865 static void scrub_page_put(struct scrub_page *spage)
1867 if (atomic_dec_and_test(&spage->ref_count)) {
1869 __free_page(spage->page);
1874 static void scrub_submit(struct scrub_ctx *sctx)
1876 struct scrub_bio *sbio;
1878 if (sctx->curr == -1)
1881 sbio = sctx->bios[sctx->curr];
1883 scrub_pending_bio_inc(sctx);
1885 if (!sbio->bio->bi_bdev) {
1887 * this case should not happen. If btrfs_map_block() is
1888 * wrong, it could happen for dev-replace operations on
1889 * missing devices when no mirrors are available, but in
1890 * this case it should already fail the mount.
1891 * This case is handled correctly (but _very_ slowly).
1893 printk_ratelimited(KERN_WARNING
1894 "btrfs: scrub_submit(bio bdev == NULL) is unexpected!\n");
1895 bio_endio(sbio->bio, -EIO);
1897 btrfsic_submit_bio(READ, sbio->bio);
1901 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx,
1902 struct scrub_page *spage)
1904 struct scrub_block *sblock = spage->sblock;
1905 struct scrub_bio *sbio;
1910 * grab a fresh bio or wait for one to become available
1912 while (sctx->curr == -1) {
1913 spin_lock(&sctx->list_lock);
1914 sctx->curr = sctx->first_free;
1915 if (sctx->curr != -1) {
1916 sctx->first_free = sctx->bios[sctx->curr]->next_free;
1917 sctx->bios[sctx->curr]->next_free = -1;
1918 sctx->bios[sctx->curr]->page_count = 0;
1919 spin_unlock(&sctx->list_lock);
1921 spin_unlock(&sctx->list_lock);
1922 wait_event(sctx->list_wait, sctx->first_free != -1);
1925 sbio = sctx->bios[sctx->curr];
1926 if (sbio->page_count == 0) {
1929 sbio->physical = spage->physical;
1930 sbio->logical = spage->logical;
1931 sbio->dev = spage->dev;
1934 bio = bio_alloc(GFP_NOFS, sctx->pages_per_rd_bio);
1940 bio->bi_private = sbio;
1941 bio->bi_end_io = scrub_bio_end_io;
1942 bio->bi_bdev = sbio->dev->bdev;
1943 bio->bi_sector = sbio->physical >> 9;
1945 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1947 sbio->logical + sbio->page_count * PAGE_SIZE !=
1949 sbio->dev != spage->dev) {
1954 sbio->pagev[sbio->page_count] = spage;
1955 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1956 if (ret != PAGE_SIZE) {
1957 if (sbio->page_count < 1) {
1966 scrub_block_get(sblock); /* one for the page added to the bio */
1967 atomic_inc(&sblock->outstanding_pages);
1969 if (sbio->page_count == sctx->pages_per_rd_bio)
1975 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
1976 u64 physical, struct btrfs_device *dev, u64 flags,
1977 u64 gen, int mirror_num, u8 *csum, int force,
1978 u64 physical_for_dev_replace)
1980 struct scrub_block *sblock;
1983 sblock = kzalloc(sizeof(*sblock), GFP_NOFS);
1985 spin_lock(&sctx->stat_lock);
1986 sctx->stat.malloc_errors++;
1987 spin_unlock(&sctx->stat_lock);
1991 /* one ref inside this function, plus one for each page added to
1993 atomic_set(&sblock->ref_count, 1);
1994 sblock->sctx = sctx;
1995 sblock->no_io_error_seen = 1;
1997 for (index = 0; len > 0; index++) {
1998 struct scrub_page *spage;
1999 u64 l = min_t(u64, len, PAGE_SIZE);
2001 spage = kzalloc(sizeof(*spage), GFP_NOFS);
2004 spin_lock(&sctx->stat_lock);
2005 sctx->stat.malloc_errors++;
2006 spin_unlock(&sctx->stat_lock);
2007 scrub_block_put(sblock);
2010 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
2011 scrub_page_get(spage);
2012 sblock->pagev[index] = spage;
2013 spage->sblock = sblock;
2015 spage->flags = flags;
2016 spage->generation = gen;
2017 spage->logical = logical;
2018 spage->physical = physical;
2019 spage->physical_for_dev_replace = physical_for_dev_replace;
2020 spage->mirror_num = mirror_num;
2022 spage->have_csum = 1;
2023 memcpy(spage->csum, csum, sctx->csum_size);
2025 spage->have_csum = 0;
2027 sblock->page_count++;
2028 spage->page = alloc_page(GFP_NOFS);
2034 physical_for_dev_replace += l;
2037 WARN_ON(sblock->page_count == 0);
2038 for (index = 0; index < sblock->page_count; index++) {
2039 struct scrub_page *spage = sblock->pagev[index];
2042 ret = scrub_add_page_to_rd_bio(sctx, spage);
2044 scrub_block_put(sblock);
2052 /* last one frees, either here or in bio completion for last page */
2053 scrub_block_put(sblock);
2057 static void scrub_bio_end_io(struct bio *bio, int err)
2059 struct scrub_bio *sbio = bio->bi_private;
2060 struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info;
2065 btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work);
2068 static void scrub_bio_end_io_worker(struct btrfs_work *work)
2070 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
2071 struct scrub_ctx *sctx = sbio->sctx;
2074 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO);
2076 for (i = 0; i < sbio->page_count; i++) {
2077 struct scrub_page *spage = sbio->pagev[i];
2079 spage->io_error = 1;
2080 spage->sblock->no_io_error_seen = 0;
2084 /* now complete the scrub_block items that have all pages completed */
2085 for (i = 0; i < sbio->page_count; i++) {
2086 struct scrub_page *spage = sbio->pagev[i];
2087 struct scrub_block *sblock = spage->sblock;
2089 if (atomic_dec_and_test(&sblock->outstanding_pages))
2090 scrub_block_complete(sblock);
2091 scrub_block_put(sblock);
2096 spin_lock(&sctx->list_lock);
2097 sbio->next_free = sctx->first_free;
2098 sctx->first_free = sbio->index;
2099 spin_unlock(&sctx->list_lock);
2101 if (sctx->is_dev_replace &&
2102 atomic_read(&sctx->wr_ctx.flush_all_writes)) {
2103 mutex_lock(&sctx->wr_ctx.wr_lock);
2104 scrub_wr_submit(sctx);
2105 mutex_unlock(&sctx->wr_ctx.wr_lock);
2108 scrub_pending_bio_dec(sctx);
2111 static void scrub_block_complete(struct scrub_block *sblock)
2113 if (!sblock->no_io_error_seen) {
2114 scrub_handle_errored_block(sblock);
2117 * if has checksum error, write via repair mechanism in
2118 * dev replace case, otherwise write here in dev replace
2121 if (!scrub_checksum(sblock) && sblock->sctx->is_dev_replace)
2122 scrub_write_block_to_dev_replace(sblock);
2126 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u64 len,
2129 struct btrfs_ordered_sum *sum = NULL;
2132 unsigned long num_sectors;
2134 while (!list_empty(&sctx->csum_list)) {
2135 sum = list_first_entry(&sctx->csum_list,
2136 struct btrfs_ordered_sum, list);
2137 if (sum->bytenr > logical)
2139 if (sum->bytenr + sum->len > logical)
2142 ++sctx->stat.csum_discards;
2143 list_del(&sum->list);
2150 num_sectors = sum->len / sctx->sectorsize;
2151 for (i = 0; i < num_sectors; ++i) {
2152 if (sum->sums[i].bytenr == logical) {
2153 memcpy(csum, &sum->sums[i].sum, sctx->csum_size);
2158 if (ret && i == num_sectors - 1) {
2159 list_del(&sum->list);
2165 /* scrub extent tries to collect up to 64 kB for each bio */
2166 static int scrub_extent(struct scrub_ctx *sctx, u64 logical, u64 len,
2167 u64 physical, struct btrfs_device *dev, u64 flags,
2168 u64 gen, int mirror_num, u64 physical_for_dev_replace)
2171 u8 csum[BTRFS_CSUM_SIZE];
2174 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2175 blocksize = sctx->sectorsize;
2176 spin_lock(&sctx->stat_lock);
2177 sctx->stat.data_extents_scrubbed++;
2178 sctx->stat.data_bytes_scrubbed += len;
2179 spin_unlock(&sctx->stat_lock);
2180 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
2181 WARN_ON(sctx->nodesize != sctx->leafsize);
2182 blocksize = sctx->nodesize;
2183 spin_lock(&sctx->stat_lock);
2184 sctx->stat.tree_extents_scrubbed++;
2185 sctx->stat.tree_bytes_scrubbed += len;
2186 spin_unlock(&sctx->stat_lock);
2188 blocksize = sctx->sectorsize;
2193 u64 l = min_t(u64, len, blocksize);
2196 if (flags & BTRFS_EXTENT_FLAG_DATA) {
2197 /* push csums to sbio */
2198 have_csum = scrub_find_csum(sctx, logical, l, csum);
2200 ++sctx->stat.no_csum;
2201 if (sctx->is_dev_replace && !have_csum) {
2202 ret = copy_nocow_pages(sctx, logical, l,
2204 physical_for_dev_replace);
2205 goto behind_scrub_pages;
2208 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen,
2209 mirror_num, have_csum ? csum : NULL, 0,
2210 physical_for_dev_replace);
2217 physical_for_dev_replace += l;
2222 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx,
2223 struct map_lookup *map,
2224 struct btrfs_device *scrub_dev,
2225 int num, u64 base, u64 length,
2228 struct btrfs_path *path;
2229 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
2230 struct btrfs_root *root = fs_info->extent_root;
2231 struct btrfs_root *csum_root = fs_info->csum_root;
2232 struct btrfs_extent_item *extent;
2233 struct blk_plug plug;
2239 struct extent_buffer *l;
2240 struct btrfs_key key;
2245 struct reada_control *reada1;
2246 struct reada_control *reada2;
2247 struct btrfs_key key_start;
2248 struct btrfs_key key_end;
2249 u64 increment = map->stripe_len;
2252 u64 extent_physical;
2254 struct btrfs_device *extent_dev;
2255 int extent_mirror_num;
2259 do_div(nstripes, map->stripe_len);
2260 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
2261 offset = map->stripe_len * num;
2262 increment = map->stripe_len * map->num_stripes;
2264 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
2265 int factor = map->num_stripes / map->sub_stripes;
2266 offset = map->stripe_len * (num / map->sub_stripes);
2267 increment = map->stripe_len * factor;
2268 mirror_num = num % map->sub_stripes + 1;
2269 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
2270 increment = map->stripe_len;
2271 mirror_num = num % map->num_stripes + 1;
2272 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
2273 increment = map->stripe_len;
2274 mirror_num = num % map->num_stripes + 1;
2276 increment = map->stripe_len;
2280 path = btrfs_alloc_path();
2285 * work on commit root. The related disk blocks are static as
2286 * long as COW is applied. This means, it is save to rewrite
2287 * them to repair disk errors without any race conditions
2289 path->search_commit_root = 1;
2290 path->skip_locking = 1;
2293 * trigger the readahead for extent tree csum tree and wait for
2294 * completion. During readahead, the scrub is officially paused
2295 * to not hold off transaction commits
2297 logical = base + offset;
2299 wait_event(sctx->list_wait,
2300 atomic_read(&sctx->bios_in_flight) == 0);
2301 atomic_inc(&fs_info->scrubs_paused);
2302 wake_up(&fs_info->scrub_pause_wait);
2304 /* FIXME it might be better to start readahead at commit root */
2305 key_start.objectid = logical;
2306 key_start.type = BTRFS_EXTENT_ITEM_KEY;
2307 key_start.offset = (u64)0;
2308 key_end.objectid = base + offset + nstripes * increment;
2309 key_end.type = BTRFS_EXTENT_ITEM_KEY;
2310 key_end.offset = (u64)0;
2311 reada1 = btrfs_reada_add(root, &key_start, &key_end);
2313 key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
2314 key_start.type = BTRFS_EXTENT_CSUM_KEY;
2315 key_start.offset = logical;
2316 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
2317 key_end.type = BTRFS_EXTENT_CSUM_KEY;
2318 key_end.offset = base + offset + nstripes * increment;
2319 reada2 = btrfs_reada_add(csum_root, &key_start, &key_end);
2321 if (!IS_ERR(reada1))
2322 btrfs_reada_wait(reada1);
2323 if (!IS_ERR(reada2))
2324 btrfs_reada_wait(reada2);
2326 mutex_lock(&fs_info->scrub_lock);
2327 while (atomic_read(&fs_info->scrub_pause_req)) {
2328 mutex_unlock(&fs_info->scrub_lock);
2329 wait_event(fs_info->scrub_pause_wait,
2330 atomic_read(&fs_info->scrub_pause_req) == 0);
2331 mutex_lock(&fs_info->scrub_lock);
2333 atomic_dec(&fs_info->scrubs_paused);
2334 mutex_unlock(&fs_info->scrub_lock);
2335 wake_up(&fs_info->scrub_pause_wait);
2338 * collect all data csums for the stripe to avoid seeking during
2339 * the scrub. This might currently (crc32) end up to be about 1MB
2341 blk_start_plug(&plug);
2344 * now find all extents for each stripe and scrub them
2346 logical = base + offset;
2347 physical = map->stripes[num].physical;
2349 for (i = 0; i < nstripes; ++i) {
2353 if (atomic_read(&fs_info->scrub_cancel_req) ||
2354 atomic_read(&sctx->cancel_req)) {
2359 * check to see if we have to pause
2361 if (atomic_read(&fs_info->scrub_pause_req)) {
2362 /* push queued extents */
2363 atomic_set(&sctx->wr_ctx.flush_all_writes, 1);
2365 mutex_lock(&sctx->wr_ctx.wr_lock);
2366 scrub_wr_submit(sctx);
2367 mutex_unlock(&sctx->wr_ctx.wr_lock);
2368 wait_event(sctx->list_wait,
2369 atomic_read(&sctx->bios_in_flight) == 0);
2370 atomic_set(&sctx->wr_ctx.flush_all_writes, 0);
2371 atomic_inc(&fs_info->scrubs_paused);
2372 wake_up(&fs_info->scrub_pause_wait);
2373 mutex_lock(&fs_info->scrub_lock);
2374 while (atomic_read(&fs_info->scrub_pause_req)) {
2375 mutex_unlock(&fs_info->scrub_lock);
2376 wait_event(fs_info->scrub_pause_wait,
2377 atomic_read(&fs_info->scrub_pause_req) == 0);
2378 mutex_lock(&fs_info->scrub_lock);
2380 atomic_dec(&fs_info->scrubs_paused);
2381 mutex_unlock(&fs_info->scrub_lock);
2382 wake_up(&fs_info->scrub_pause_wait);
2385 ret = btrfs_lookup_csums_range(csum_root, logical,
2386 logical + map->stripe_len - 1,
2387 &sctx->csum_list, 1);
2391 key.objectid = logical;
2392 key.type = BTRFS_EXTENT_ITEM_KEY;
2393 key.offset = (u64)0;
2395 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2399 ret = btrfs_previous_item(root, path, 0,
2400 BTRFS_EXTENT_ITEM_KEY);
2404 /* there's no smaller item, so stick with the
2406 btrfs_release_path(path);
2407 ret = btrfs_search_slot(NULL, root, &key,
2416 slot = path->slots[0];
2417 if (slot >= btrfs_header_nritems(l)) {
2418 ret = btrfs_next_leaf(root, path);
2426 btrfs_item_key_to_cpu(l, &key, slot);
2428 if (key.objectid + key.offset <= logical)
2431 if (key.objectid >= logical + map->stripe_len)
2434 if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
2437 extent = btrfs_item_ptr(l, slot,
2438 struct btrfs_extent_item);
2439 flags = btrfs_extent_flags(l, extent);
2440 generation = btrfs_extent_generation(l, extent);
2442 if (key.objectid < logical &&
2443 (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
2445 "btrfs scrub: tree block %llu spanning "
2446 "stripes, ignored. logical=%llu\n",
2447 (unsigned long long)key.objectid,
2448 (unsigned long long)logical);
2453 * trim extent to this stripe
2455 if (key.objectid < logical) {
2456 key.offset -= logical - key.objectid;
2457 key.objectid = logical;
2459 if (key.objectid + key.offset >
2460 logical + map->stripe_len) {
2461 key.offset = logical + map->stripe_len -
2465 extent_logical = key.objectid;
2466 extent_physical = key.objectid - logical + physical;
2467 extent_len = key.offset;
2468 extent_dev = scrub_dev;
2469 extent_mirror_num = mirror_num;
2471 scrub_remap_extent(fs_info, extent_logical,
2472 extent_len, &extent_physical,
2474 &extent_mirror_num);
2475 ret = scrub_extent(sctx, extent_logical, extent_len,
2476 extent_physical, extent_dev, flags,
2477 generation, extent_mirror_num,
2478 key.objectid - logical + physical);
2485 btrfs_release_path(path);
2486 logical += increment;
2487 physical += map->stripe_len;
2488 spin_lock(&sctx->stat_lock);
2489 sctx->stat.last_physical = physical;
2490 spin_unlock(&sctx->stat_lock);
2493 /* push queued extents */
2495 mutex_lock(&sctx->wr_ctx.wr_lock);
2496 scrub_wr_submit(sctx);
2497 mutex_unlock(&sctx->wr_ctx.wr_lock);
2499 blk_finish_plug(&plug);
2500 btrfs_free_path(path);
2501 return ret < 0 ? ret : 0;
2504 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx,
2505 struct btrfs_device *scrub_dev,
2506 u64 chunk_tree, u64 chunk_objectid,
2507 u64 chunk_offset, u64 length,
2508 u64 dev_offset, int is_dev_replace)
2510 struct btrfs_mapping_tree *map_tree =
2511 &sctx->dev_root->fs_info->mapping_tree;
2512 struct map_lookup *map;
2513 struct extent_map *em;
2517 read_lock(&map_tree->map_tree.lock);
2518 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
2519 read_unlock(&map_tree->map_tree.lock);
2524 map = (struct map_lookup *)em->bdev;
2525 if (em->start != chunk_offset)
2528 if (em->len < length)
2531 for (i = 0; i < map->num_stripes; ++i) {
2532 if (map->stripes[i].dev->bdev == scrub_dev->bdev &&
2533 map->stripes[i].physical == dev_offset) {
2534 ret = scrub_stripe(sctx, map, scrub_dev, i,
2535 chunk_offset, length,
2542 free_extent_map(em);
2547 static noinline_for_stack
2548 int scrub_enumerate_chunks(struct scrub_ctx *sctx,
2549 struct btrfs_device *scrub_dev, u64 start, u64 end,
2552 struct btrfs_dev_extent *dev_extent = NULL;
2553 struct btrfs_path *path;
2554 struct btrfs_root *root = sctx->dev_root;
2555 struct btrfs_fs_info *fs_info = root->fs_info;
2562 struct extent_buffer *l;
2563 struct btrfs_key key;
2564 struct btrfs_key found_key;
2565 struct btrfs_block_group_cache *cache;
2566 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
2568 path = btrfs_alloc_path();
2573 path->search_commit_root = 1;
2574 path->skip_locking = 1;
2576 key.objectid = scrub_dev->devid;
2578 key.type = BTRFS_DEV_EXTENT_KEY;
2581 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2585 if (path->slots[0] >=
2586 btrfs_header_nritems(path->nodes[0])) {
2587 ret = btrfs_next_leaf(root, path);
2594 slot = path->slots[0];
2596 btrfs_item_key_to_cpu(l, &found_key, slot);
2598 if (found_key.objectid != scrub_dev->devid)
2601 if (btrfs_key_type(&found_key) != BTRFS_DEV_EXTENT_KEY)
2604 if (found_key.offset >= end)
2607 if (found_key.offset < key.offset)
2610 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2611 length = btrfs_dev_extent_length(l, dev_extent);
2613 if (found_key.offset + length <= start) {
2614 key.offset = found_key.offset + length;
2615 btrfs_release_path(path);
2619 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2620 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2621 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2624 * get a reference on the corresponding block group to prevent
2625 * the chunk from going away while we scrub it
2627 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2632 dev_replace->cursor_right = found_key.offset + length;
2633 dev_replace->cursor_left = found_key.offset;
2634 dev_replace->item_needs_writeback = 1;
2635 ret = scrub_chunk(sctx, scrub_dev, chunk_tree, chunk_objectid,
2636 chunk_offset, length, found_key.offset,
2640 * flush, submit all pending read and write bios, afterwards
2642 * Note that in the dev replace case, a read request causes
2643 * write requests that are submitted in the read completion
2644 * worker. Therefore in the current situation, it is required
2645 * that all write requests are flushed, so that all read and
2646 * write requests are really completed when bios_in_flight
2649 atomic_set(&sctx->wr_ctx.flush_all_writes, 1);
2651 mutex_lock(&sctx->wr_ctx.wr_lock);
2652 scrub_wr_submit(sctx);
2653 mutex_unlock(&sctx->wr_ctx.wr_lock);
2655 wait_event(sctx->list_wait,
2656 atomic_read(&sctx->bios_in_flight) == 0);
2657 atomic_set(&sctx->wr_ctx.flush_all_writes, 0);
2658 atomic_inc(&fs_info->scrubs_paused);
2659 wake_up(&fs_info->scrub_pause_wait);
2660 wait_event(sctx->list_wait,
2661 atomic_read(&sctx->workers_pending) == 0);
2663 mutex_lock(&fs_info->scrub_lock);
2664 while (atomic_read(&fs_info->scrub_pause_req)) {
2665 mutex_unlock(&fs_info->scrub_lock);
2666 wait_event(fs_info->scrub_pause_wait,
2667 atomic_read(&fs_info->scrub_pause_req) == 0);
2668 mutex_lock(&fs_info->scrub_lock);
2670 atomic_dec(&fs_info->scrubs_paused);
2671 mutex_unlock(&fs_info->scrub_lock);
2672 wake_up(&fs_info->scrub_pause_wait);
2674 dev_replace->cursor_left = dev_replace->cursor_right;
2675 dev_replace->item_needs_writeback = 1;
2676 btrfs_put_block_group(cache);
2679 if (is_dev_replace &&
2680 atomic64_read(&dev_replace->num_write_errors) > 0) {
2684 if (sctx->stat.malloc_errors > 0) {
2689 key.offset = found_key.offset + length;
2690 btrfs_release_path(path);
2693 btrfs_free_path(path);
2696 * ret can still be 1 from search_slot or next_leaf,
2697 * that's not an error
2699 return ret < 0 ? ret : 0;
2702 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx,
2703 struct btrfs_device *scrub_dev)
2709 struct btrfs_root *root = sctx->dev_root;
2711 if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
2714 gen = root->fs_info->last_trans_committed;
2716 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
2717 bytenr = btrfs_sb_offset(i);
2718 if (bytenr + BTRFS_SUPER_INFO_SIZE > scrub_dev->total_bytes)
2721 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
2722 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i,
2727 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
2733 * get a reference count on fs_info->scrub_workers. start worker if necessary
2735 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info,
2740 mutex_lock(&fs_info->scrub_lock);
2741 if (fs_info->scrub_workers_refcnt == 0) {
2743 btrfs_init_workers(&fs_info->scrub_workers, "scrub", 1,
2744 &fs_info->generic_worker);
2746 btrfs_init_workers(&fs_info->scrub_workers, "scrub",
2747 fs_info->thread_pool_size,
2748 &fs_info->generic_worker);
2749 fs_info->scrub_workers.idle_thresh = 4;
2750 ret = btrfs_start_workers(&fs_info->scrub_workers);
2753 btrfs_init_workers(&fs_info->scrub_wr_completion_workers,
2755 fs_info->thread_pool_size,
2756 &fs_info->generic_worker);
2757 fs_info->scrub_wr_completion_workers.idle_thresh = 2;
2758 ret = btrfs_start_workers(
2759 &fs_info->scrub_wr_completion_workers);
2762 btrfs_init_workers(&fs_info->scrub_nocow_workers, "scrubnc", 1,
2763 &fs_info->generic_worker);
2764 ret = btrfs_start_workers(&fs_info->scrub_nocow_workers);
2768 ++fs_info->scrub_workers_refcnt;
2770 mutex_unlock(&fs_info->scrub_lock);
2775 static noinline_for_stack void scrub_workers_put(struct btrfs_fs_info *fs_info)
2777 mutex_lock(&fs_info->scrub_lock);
2778 if (--fs_info->scrub_workers_refcnt == 0) {
2779 btrfs_stop_workers(&fs_info->scrub_workers);
2780 btrfs_stop_workers(&fs_info->scrub_wr_completion_workers);
2781 btrfs_stop_workers(&fs_info->scrub_nocow_workers);
2783 WARN_ON(fs_info->scrub_workers_refcnt < 0);
2784 mutex_unlock(&fs_info->scrub_lock);
2787 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start,
2788 u64 end, struct btrfs_scrub_progress *progress,
2789 int readonly, int is_dev_replace)
2791 struct scrub_ctx *sctx;
2793 struct btrfs_device *dev;
2795 if (btrfs_fs_closing(fs_info))
2799 * check some assumptions
2801 if (fs_info->chunk_root->nodesize != fs_info->chunk_root->leafsize) {
2803 "btrfs_scrub: size assumption nodesize == leafsize (%d == %d) fails\n",
2804 fs_info->chunk_root->nodesize,
2805 fs_info->chunk_root->leafsize);
2809 if (fs_info->chunk_root->nodesize > BTRFS_STRIPE_LEN) {
2811 * in this case scrub is unable to calculate the checksum
2812 * the way scrub is implemented. Do not handle this
2813 * situation at all because it won't ever happen.
2816 "btrfs_scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails\n",
2817 fs_info->chunk_root->nodesize, BTRFS_STRIPE_LEN);
2821 if (fs_info->chunk_root->sectorsize != PAGE_SIZE) {
2822 /* not supported for data w/o checksums */
2824 "btrfs_scrub: size assumption sectorsize != PAGE_SIZE (%d != %lld) fails\n",
2825 fs_info->chunk_root->sectorsize,
2826 (unsigned long long)PAGE_SIZE);
2830 if (fs_info->chunk_root->nodesize >
2831 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK ||
2832 fs_info->chunk_root->sectorsize >
2833 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) {
2835 * would exhaust the array bounds of pagev member in
2836 * struct scrub_block
2838 pr_err("btrfs_scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails\n",
2839 fs_info->chunk_root->nodesize,
2840 SCRUB_MAX_PAGES_PER_BLOCK,
2841 fs_info->chunk_root->sectorsize,
2842 SCRUB_MAX_PAGES_PER_BLOCK);
2846 ret = scrub_workers_get(fs_info, is_dev_replace);
2850 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2851 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
2852 if (!dev || (dev->missing && !is_dev_replace)) {
2853 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2854 scrub_workers_put(fs_info);
2857 mutex_lock(&fs_info->scrub_lock);
2859 if (!dev->in_fs_metadata || dev->is_tgtdev_for_dev_replace) {
2860 mutex_unlock(&fs_info->scrub_lock);
2861 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2862 scrub_workers_put(fs_info);
2866 btrfs_dev_replace_lock(&fs_info->dev_replace);
2867 if (dev->scrub_device ||
2869 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) {
2870 btrfs_dev_replace_unlock(&fs_info->dev_replace);
2871 mutex_unlock(&fs_info->scrub_lock);
2872 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2873 scrub_workers_put(fs_info);
2874 return -EINPROGRESS;
2876 btrfs_dev_replace_unlock(&fs_info->dev_replace);
2877 sctx = scrub_setup_ctx(dev, is_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 PTR_ERR(sctx);
2884 sctx->readonly = readonly;
2885 dev->scrub_device = sctx;
2887 atomic_inc(&fs_info->scrubs_running);
2888 mutex_unlock(&fs_info->scrub_lock);
2889 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2891 if (!is_dev_replace) {
2892 down_read(&fs_info->scrub_super_lock);
2893 ret = scrub_supers(sctx, dev);
2894 up_read(&fs_info->scrub_super_lock);
2898 ret = scrub_enumerate_chunks(sctx, dev, start, end,
2901 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0);
2902 atomic_dec(&fs_info->scrubs_running);
2903 wake_up(&fs_info->scrub_pause_wait);
2905 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0);
2908 memcpy(progress, &sctx->stat, sizeof(*progress));
2910 mutex_lock(&fs_info->scrub_lock);
2911 dev->scrub_device = NULL;
2912 mutex_unlock(&fs_info->scrub_lock);
2914 scrub_free_ctx(sctx);
2915 scrub_workers_put(fs_info);
2920 void btrfs_scrub_pause(struct btrfs_root *root)
2922 struct btrfs_fs_info *fs_info = root->fs_info;
2924 mutex_lock(&fs_info->scrub_lock);
2925 atomic_inc(&fs_info->scrub_pause_req);
2926 while (atomic_read(&fs_info->scrubs_paused) !=
2927 atomic_read(&fs_info->scrubs_running)) {
2928 mutex_unlock(&fs_info->scrub_lock);
2929 wait_event(fs_info->scrub_pause_wait,
2930 atomic_read(&fs_info->scrubs_paused) ==
2931 atomic_read(&fs_info->scrubs_running));
2932 mutex_lock(&fs_info->scrub_lock);
2934 mutex_unlock(&fs_info->scrub_lock);
2937 void btrfs_scrub_continue(struct btrfs_root *root)
2939 struct btrfs_fs_info *fs_info = root->fs_info;
2941 atomic_dec(&fs_info->scrub_pause_req);
2942 wake_up(&fs_info->scrub_pause_wait);
2945 void btrfs_scrub_pause_super(struct btrfs_root *root)
2947 down_write(&root->fs_info->scrub_super_lock);
2950 void btrfs_scrub_continue_super(struct btrfs_root *root)
2952 up_write(&root->fs_info->scrub_super_lock);
2955 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
2957 mutex_lock(&fs_info->scrub_lock);
2958 if (!atomic_read(&fs_info->scrubs_running)) {
2959 mutex_unlock(&fs_info->scrub_lock);
2963 atomic_inc(&fs_info->scrub_cancel_req);
2964 while (atomic_read(&fs_info->scrubs_running)) {
2965 mutex_unlock(&fs_info->scrub_lock);
2966 wait_event(fs_info->scrub_pause_wait,
2967 atomic_read(&fs_info->scrubs_running) == 0);
2968 mutex_lock(&fs_info->scrub_lock);
2970 atomic_dec(&fs_info->scrub_cancel_req);
2971 mutex_unlock(&fs_info->scrub_lock);
2976 int btrfs_scrub_cancel_dev(struct btrfs_fs_info *fs_info,
2977 struct btrfs_device *dev)
2979 struct scrub_ctx *sctx;
2981 mutex_lock(&fs_info->scrub_lock);
2982 sctx = dev->scrub_device;
2984 mutex_unlock(&fs_info->scrub_lock);
2987 atomic_inc(&sctx->cancel_req);
2988 while (dev->scrub_device) {
2989 mutex_unlock(&fs_info->scrub_lock);
2990 wait_event(fs_info->scrub_pause_wait,
2991 dev->scrub_device == NULL);
2992 mutex_lock(&fs_info->scrub_lock);
2994 mutex_unlock(&fs_info->scrub_lock);
2999 int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid)
3001 struct btrfs_fs_info *fs_info = root->fs_info;
3002 struct btrfs_device *dev;
3006 * we have to hold the device_list_mutex here so the device
3007 * does not go away in cancel_dev. FIXME: find a better solution
3009 mutex_lock(&fs_info->fs_devices->device_list_mutex);
3010 dev = btrfs_find_device(fs_info, devid, NULL, NULL);
3012 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3015 ret = btrfs_scrub_cancel_dev(fs_info, dev);
3016 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
3021 int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
3022 struct btrfs_scrub_progress *progress)
3024 struct btrfs_device *dev;
3025 struct scrub_ctx *sctx = NULL;
3027 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
3028 dev = btrfs_find_device(root->fs_info, devid, NULL, NULL);
3030 sctx = dev->scrub_device;
3032 memcpy(progress, &sctx->stat, sizeof(*progress));
3033 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
3035 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV;
3038 static void scrub_remap_extent(struct btrfs_fs_info *fs_info,
3039 u64 extent_logical, u64 extent_len,
3040 u64 *extent_physical,
3041 struct btrfs_device **extent_dev,
3042 int *extent_mirror_num)
3045 struct btrfs_bio *bbio = NULL;
3048 mapped_length = extent_len;
3049 ret = btrfs_map_block(fs_info, READ, extent_logical,
3050 &mapped_length, &bbio, 0);
3051 if (ret || !bbio || mapped_length < extent_len ||
3052 !bbio->stripes[0].dev->bdev) {
3057 *extent_physical = bbio->stripes[0].physical;
3058 *extent_mirror_num = bbio->mirror_num;
3059 *extent_dev = bbio->stripes[0].dev;
3063 static int scrub_setup_wr_ctx(struct scrub_ctx *sctx,
3064 struct scrub_wr_ctx *wr_ctx,
3065 struct btrfs_fs_info *fs_info,
3066 struct btrfs_device *dev,
3069 WARN_ON(wr_ctx->wr_curr_bio != NULL);
3071 mutex_init(&wr_ctx->wr_lock);
3072 wr_ctx->wr_curr_bio = NULL;
3073 if (!is_dev_replace)
3076 WARN_ON(!dev->bdev);
3077 wr_ctx->pages_per_wr_bio = min_t(int, SCRUB_PAGES_PER_WR_BIO,
3078 bio_get_nr_vecs(dev->bdev));
3079 wr_ctx->tgtdev = dev;
3080 atomic_set(&wr_ctx->flush_all_writes, 0);
3084 static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx)
3086 mutex_lock(&wr_ctx->wr_lock);
3087 kfree(wr_ctx->wr_curr_bio);
3088 wr_ctx->wr_curr_bio = NULL;
3089 mutex_unlock(&wr_ctx->wr_lock);
3092 static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, u64 len,
3093 int mirror_num, u64 physical_for_dev_replace)
3095 struct scrub_copy_nocow_ctx *nocow_ctx;
3096 struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info;
3098 nocow_ctx = kzalloc(sizeof(*nocow_ctx), GFP_NOFS);
3100 spin_lock(&sctx->stat_lock);
3101 sctx->stat.malloc_errors++;
3102 spin_unlock(&sctx->stat_lock);
3106 scrub_pending_trans_workers_inc(sctx);
3108 nocow_ctx->sctx = sctx;
3109 nocow_ctx->logical = logical;
3110 nocow_ctx->len = len;
3111 nocow_ctx->mirror_num = mirror_num;
3112 nocow_ctx->physical_for_dev_replace = physical_for_dev_replace;
3113 nocow_ctx->work.func = copy_nocow_pages_worker;
3114 btrfs_queue_worker(&fs_info->scrub_nocow_workers,
3120 static void copy_nocow_pages_worker(struct btrfs_work *work)
3122 struct scrub_copy_nocow_ctx *nocow_ctx =
3123 container_of(work, struct scrub_copy_nocow_ctx, work);
3124 struct scrub_ctx *sctx = nocow_ctx->sctx;
3125 u64 logical = nocow_ctx->logical;
3126 u64 len = nocow_ctx->len;
3127 int mirror_num = nocow_ctx->mirror_num;
3128 u64 physical_for_dev_replace = nocow_ctx->physical_for_dev_replace;
3130 struct btrfs_trans_handle *trans = NULL;
3131 struct btrfs_fs_info *fs_info;
3132 struct btrfs_path *path;
3133 struct btrfs_root *root;
3134 int not_written = 0;
3136 fs_info = sctx->dev_root->fs_info;
3137 root = fs_info->extent_root;
3139 path = btrfs_alloc_path();
3141 spin_lock(&sctx->stat_lock);
3142 sctx->stat.malloc_errors++;
3143 spin_unlock(&sctx->stat_lock);
3148 trans = btrfs_join_transaction(root);
3149 if (IS_ERR(trans)) {
3154 ret = iterate_inodes_from_logical(logical, fs_info, path,
3155 copy_nocow_pages_for_inode,
3157 if (ret != 0 && ret != -ENOENT) {
3158 pr_warn("iterate_inodes_from_logical() failed: log %llu, phys %llu, len %llu, mir %llu, ret %d\n",
3159 (unsigned long long)logical,
3160 (unsigned long long)physical_for_dev_replace,
3161 (unsigned long long)len,
3162 (unsigned long long)mirror_num, ret);
3168 if (trans && !IS_ERR(trans))
3169 btrfs_end_transaction(trans, root);
3171 btrfs_dev_replace_stats_inc(&fs_info->dev_replace.
3172 num_uncorrectable_read_errors);
3174 btrfs_free_path(path);
3177 scrub_pending_trans_workers_dec(sctx);
3180 static int copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root, void *ctx)
3182 unsigned long index;
3183 struct scrub_copy_nocow_ctx *nocow_ctx = ctx;
3185 struct btrfs_key key;
3186 struct inode *inode = NULL;
3187 struct btrfs_root *local_root;
3188 u64 physical_for_dev_replace;
3190 struct btrfs_fs_info *fs_info = nocow_ctx->sctx->dev_root->fs_info;
3193 key.objectid = root;
3194 key.type = BTRFS_ROOT_ITEM_KEY;
3195 key.offset = (u64)-1;
3197 srcu_index = srcu_read_lock(&fs_info->subvol_srcu);
3199 local_root = btrfs_read_fs_root_no_name(fs_info, &key);
3200 if (IS_ERR(local_root)) {
3201 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
3202 return PTR_ERR(local_root);
3205 key.type = BTRFS_INODE_ITEM_KEY;
3206 key.objectid = inum;
3208 inode = btrfs_iget(fs_info->sb, &key, local_root, NULL);
3209 srcu_read_unlock(&fs_info->subvol_srcu, srcu_index);
3211 return PTR_ERR(inode);
3213 physical_for_dev_replace = nocow_ctx->physical_for_dev_replace;
3214 len = nocow_ctx->len;
3215 while (len >= PAGE_CACHE_SIZE) {
3216 struct page *page = NULL;
3219 index = offset >> PAGE_CACHE_SHIFT;
3221 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
3223 pr_err("find_or_create_page() failed\n");
3228 if (PageUptodate(page)) {
3229 if (PageDirty(page))
3232 ClearPageError(page);
3233 ret_sub = extent_read_full_page(&BTRFS_I(inode)->
3235 page, btrfs_get_extent,
3236 nocow_ctx->mirror_num);
3241 wait_on_page_locked(page);
3242 if (!PageUptodate(page)) {
3247 ret_sub = write_page_nocow(nocow_ctx->sctx,
3248 physical_for_dev_replace, page);
3259 offset += PAGE_CACHE_SIZE;
3260 physical_for_dev_replace += PAGE_CACHE_SIZE;
3261 len -= PAGE_CACHE_SIZE;
3269 static int write_page_nocow(struct scrub_ctx *sctx,
3270 u64 physical_for_dev_replace, struct page *page)
3273 struct btrfs_device *dev;
3275 DECLARE_COMPLETION_ONSTACK(compl);
3277 dev = sctx->wr_ctx.tgtdev;
3281 printk_ratelimited(KERN_WARNING
3282 "btrfs: scrub write_page_nocow(bdev == NULL) is unexpected!\n");
3285 bio = bio_alloc(GFP_NOFS, 1);
3287 spin_lock(&sctx->stat_lock);
3288 sctx->stat.malloc_errors++;
3289 spin_unlock(&sctx->stat_lock);
3292 bio->bi_private = &compl;
3293 bio->bi_end_io = scrub_complete_bio_end_io;
3295 bio->bi_sector = physical_for_dev_replace >> 9;
3296 bio->bi_bdev = dev->bdev;
3297 ret = bio_add_page(bio, page, PAGE_CACHE_SIZE, 0);
3298 if (ret != PAGE_CACHE_SIZE) {
3301 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS);
3304 btrfsic_submit_bio(WRITE_SYNC, bio);
3305 wait_for_completion(&compl);
3307 if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
3308 goto leave_with_eio;