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Btrfs: remove lock assert from get_restripe_target()
[deliverable/linux.git] / fs / btrfs / scrub.c
CommitLineData
a2de733c
AJ		 1/*
2 * Copyright (C) 2011 STRATO. All rights reserved.
3 *
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.
7 *
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.
12 *
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.
17 */
18
a2de733c 19#include <linux/blkdev.h>
558540c1 20#include <linux/ratelimit.h>
a2de733c
AJ		 21#include "ctree.h"
22#include "volumes.h"
23#include "disk-io.h"
24#include "ordered-data.h"
0ef8e451 25#include "transaction.h"
558540c1 26#include "backref.h"
5da6fcbc 27#include "extent_io.h"
21adbd5c 28#include "check-integrity.h"
a2de733c
AJ		 29
30/*
31 * This is only the first step towards a full-features scrub. It reads all
32 * extent and super block and verifies the checksums. In case a bad checksum
33 * is found or the extent cannot be read, good data will be written back if
34 * any can be found.
35 *
36 * Future enhancements:
a2de733c
AJ		 37 * - In case an unrepairable extent is encountered, track which files are
38 * affected and report them
a2de733c 39 * - track and record media errors, throw out bad devices
a2de733c 40 * - add a mode to also read unallocated space
a2de733c
AJ		 41 */
42
b5d67f64 43struct scrub_block;
a2de733c 44struct scrub_dev;
a2de733c
AJ		 45
46#define SCRUB_PAGES_PER_BIO 16 /* 64k per bio */
47#define SCRUB_BIOS_PER_DEV 16 /* 1 MB per device in flight */
b5d67f64 48#define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */
a2de733c
AJ		 49
50struct scrub_page {
b5d67f64
SB		 51 struct scrub_block *sblock;
52 struct page *page;
53 struct block_device *bdev;
a2de733c
AJ		 54 u64 flags; /* extent flags */
55 u64 generation;
b5d67f64
SB		 56 u64 logical;
57 u64 physical;
58 struct {
59 unsigned int mirror_num:8;
60 unsigned int have_csum:1;
61 unsigned int io_error:1;
62 };
a2de733c
AJ		 63 u8 csum[BTRFS_CSUM_SIZE];
64};
65
66struct scrub_bio {
67 int index;
68 struct scrub_dev *sdev;
69 struct bio *bio;
70 int err;
71 u64 logical;
72 u64 physical;
b5d67f64
SB		 73 struct scrub_page *pagev[SCRUB_PAGES_PER_BIO];
74 int page_count;
a2de733c
AJ		 75 int next_free;
76 struct btrfs_work work;
77};
78
b5d67f64
SB		 79struct scrub_block {
80 struct scrub_page pagev[SCRUB_MAX_PAGES_PER_BLOCK];
81 int page_count;
82 atomic_t outstanding_pages;
83 atomic_t ref_count; /* free mem on transition to zero */
84 struct scrub_dev *sdev;
85 struct {
86 unsigned int header_error:1;
87 unsigned int checksum_error:1;
88 unsigned int no_io_error_seen:1;
89 };
90};
91
a2de733c
AJ		 92struct scrub_dev {
93 struct scrub_bio *bios[SCRUB_BIOS_PER_DEV];
94 struct btrfs_device *dev;
95 int first_free;
96 int curr;
97 atomic_t in_flight;
0ef8e451 98 atomic_t fixup_cnt;
a2de733c
AJ		 99 spinlock_t list_lock;
100 wait_queue_head_t list_wait;
101 u16 csum_size;
102 struct list_head csum_list;
103 atomic_t cancel_req;
8628764e 104 int readonly;
b5d67f64
SB		 105 int pages_per_bio; /* <= SCRUB_PAGES_PER_BIO */
106 u32 sectorsize;
107 u32 nodesize;
108 u32 leafsize;
a2de733c
AJ		 109 /*
110 * statistics
111 */
112 struct btrfs_scrub_progress stat;
113 spinlock_t stat_lock;
114};
115
0ef8e451
JS		 116struct scrub_fixup_nodatasum {
117 struct scrub_dev *sdev;
118 u64 logical;
119 struct btrfs_root *root;
120 struct btrfs_work work;
121 int mirror_num;
122};
123
558540c1
JS		 124struct scrub_warning {
125 struct btrfs_path *path;
126 u64 extent_item_size;
127 char *scratch_buf;
128 char *msg_buf;
129 const char *errstr;
130 sector_t sector;
131 u64 logical;
132 struct btrfs_device *dev;
133 int msg_bufsize;
134 int scratch_bufsize;
135};
136
b5d67f64
SB		 137
138static int scrub_handle_errored_block(struct scrub_block *sblock_to_check);
139static int scrub_setup_recheck_block(struct scrub_dev *sdev,
140 struct btrfs_mapping_tree *map_tree,
141 u64 length, u64 logical,
142 struct scrub_block *sblock);
143static int scrub_recheck_block(struct btrfs_fs_info *fs_info,
144 struct scrub_block *sblock, int is_metadata,
145 int have_csum, u8 *csum, u64 generation,
146 u16 csum_size);
147static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
148 struct scrub_block *sblock,
149 int is_metadata, int have_csum,
150 const u8 *csum, u64 generation,
151 u16 csum_size);
152static void scrub_complete_bio_end_io(struct bio *bio, int err);
153static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
154 struct scrub_block *sblock_good,
155 int force_write);
156static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
157 struct scrub_block *sblock_good,
158 int page_num, int force_write);
159static int scrub_checksum_data(struct scrub_block *sblock);
160static int scrub_checksum_tree_block(struct scrub_block *sblock);
161static int scrub_checksum_super(struct scrub_block *sblock);
162static void scrub_block_get(struct scrub_block *sblock);
163static void scrub_block_put(struct scrub_block *sblock);
164static int scrub_add_page_to_bio(struct scrub_dev *sdev,
165 struct scrub_page *spage);
166static int scrub_pages(struct scrub_dev *sdev, u64 logical, u64 len,
167 u64 physical, u64 flags, u64 gen, int mirror_num,
168 u8 *csum, int force);
1623edeb 169static void scrub_bio_end_io(struct bio *bio, int err);
b5d67f64
SB		 170static void scrub_bio_end_io_worker(struct btrfs_work *work);
171static void scrub_block_complete(struct scrub_block *sblock);
1623edeb
SB		 172
173
a2de733c
AJ		 174static void scrub_free_csums(struct scrub_dev *sdev)
175{
176 while (!list_empty(&sdev->csum_list)) {
177 struct btrfs_ordered_sum *sum;
178 sum = list_first_entry(&sdev->csum_list,
179 struct btrfs_ordered_sum, list);
180 list_del(&sum->list);
181 kfree(sum);
182 }
183}
184
185static noinline_for_stack void scrub_free_dev(struct scrub_dev *sdev)
186{
187 int i;
a2de733c
AJ		 188
189 if (!sdev)
190 return;
191
b5d67f64
SB		 192 /* this can happen when scrub is cancelled */
193 if (sdev->curr != -1) {
194 struct scrub_bio *sbio = sdev->bios[sdev->curr];
195
196 for (i = 0; i < sbio->page_count; i++) {
197 BUG_ON(!sbio->pagev[i]);
198 BUG_ON(!sbio->pagev[i]->page);
199 scrub_block_put(sbio->pagev[i]->sblock);
200 }
201 bio_put(sbio->bio);
202 }
203
a2de733c
AJ		 204 for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) {
205 struct scrub_bio *sbio = sdev->bios[i];
a2de733c
AJ		 206
207 if (!sbio)
208 break;
a2de733c
AJ		 209 kfree(sbio);
210 }
211
212 scrub_free_csums(sdev);
213 kfree(sdev);
214}
215
216static noinline_for_stack
217struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev)
218{
219 struct scrub_dev *sdev;
220 int i;
a2de733c 221 struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
b5d67f64 222 int pages_per_bio;
a2de733c 223
b5d67f64
SB		 224 pages_per_bio = min_t(int, SCRUB_PAGES_PER_BIO,
225 bio_get_nr_vecs(dev->bdev));
a2de733c
AJ		 226 sdev = kzalloc(sizeof(*sdev), GFP_NOFS);
227 if (!sdev)
228 goto nomem;
229 sdev->dev = dev;
b5d67f64
SB		 230 sdev->pages_per_bio = pages_per_bio;
231 sdev->curr = -1;
a2de733c 232 for (i = 0; i < SCRUB_BIOS_PER_DEV; ++i) {
a2de733c
AJ		 233 struct scrub_bio *sbio;
234
235 sbio = kzalloc(sizeof(*sbio), GFP_NOFS);
236 if (!sbio)
237 goto nomem;
238 sdev->bios[i] = sbio;
239
a2de733c
AJ		 240 sbio->index = i;
241 sbio->sdev = sdev;
b5d67f64
SB		 242 sbio->page_count = 0;
243 sbio->work.func = scrub_bio_end_io_worker;
a2de733c
AJ		 244
245 if (i != SCRUB_BIOS_PER_DEV-1)
246 sdev->bios[i]->next_free = i + 1;
0ef8e451 247 else
a2de733c
AJ		 248 sdev->bios[i]->next_free = -1;
249 }
250 sdev->first_free = 0;
b5d67f64
SB		 251 sdev->nodesize = dev->dev_root->nodesize;
252 sdev->leafsize = dev->dev_root->leafsize;
253 sdev->sectorsize = dev->dev_root->sectorsize;
a2de733c 254 atomic_set(&sdev->in_flight, 0);
0ef8e451 255 atomic_set(&sdev->fixup_cnt, 0);
a2de733c 256 atomic_set(&sdev->cancel_req, 0);
6c41761f 257 sdev->csum_size = btrfs_super_csum_size(fs_info->super_copy);
a2de733c
AJ		 258 INIT_LIST_HEAD(&sdev->csum_list);
259
260 spin_lock_init(&sdev->list_lock);
261 spin_lock_init(&sdev->stat_lock);
262 init_waitqueue_head(&sdev->list_wait);
263 return sdev;
264
265nomem:
266 scrub_free_dev(sdev);
267 return ERR_PTR(-ENOMEM);
268}
269
558540c1
JS		 270static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
271{
272 u64 isize;
273 u32 nlink;
274 int ret;
275 int i;
276 struct extent_buffer *eb;
277 struct btrfs_inode_item *inode_item;
278 struct scrub_warning *swarn = ctx;
279 struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info;
280 struct inode_fs_paths *ipath = NULL;
281 struct btrfs_root *local_root;
282 struct btrfs_key root_key;
283
284 root_key.objectid = root;
285 root_key.type = BTRFS_ROOT_ITEM_KEY;
286 root_key.offset = (u64)-1;
287 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key);
288 if (IS_ERR(local_root)) {
289 ret = PTR_ERR(local_root);
290 goto err;
291 }
292
293 ret = inode_item_info(inum, 0, local_root, swarn->path);
294 if (ret) {
295 btrfs_release_path(swarn->path);
296 goto err;
297 }
298
299 eb = swarn->path->nodes[0];
300 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0],
301 struct btrfs_inode_item);
302 isize = btrfs_inode_size(eb, inode_item);
303 nlink = btrfs_inode_nlink(eb, inode_item);
304 btrfs_release_path(swarn->path);
305
306 ipath = init_ipath(4096, local_root, swarn->path);
26bdef54
DC		 307 if (IS_ERR(ipath)) {
308 ret = PTR_ERR(ipath);
309 ipath = NULL;
310 goto err;
311 }
558540c1
JS		 312 ret = paths_from_inode(inum, ipath);
313
314 if (ret < 0)
315 goto err;
316
317 /*
318 * we deliberately ignore the bit ipath might have been too small to
319 * hold all of the paths here
320 */
321 for (i = 0; i < ipath->fspath->elem_cnt; ++i)
322 printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
323 "%s, sector %llu, root %llu, inode %llu, offset %llu, "
324 "length %llu, links %u (path: %s)\n", swarn->errstr,
325 swarn->logical, swarn->dev->name,
326 (unsigned long long)swarn->sector, root, inum, offset,
327 min(isize - offset, (u64)PAGE_SIZE), nlink,
745c4d8e 328 (char *)(unsigned long)ipath->fspath->val[i]);
558540c1
JS		 329
330 free_ipath(ipath);
331 return 0;
332
333err:
334 printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
335 "%s, sector %llu, root %llu, inode %llu, offset %llu: path "
336 "resolving failed with ret=%d\n", swarn->errstr,
337 swarn->logical, swarn->dev->name,
338 (unsigned long long)swarn->sector, root, inum, offset, ret);
339
340 free_ipath(ipath);
341 return 0;
342}
343
b5d67f64 344static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
558540c1 345{
b5d67f64 346 struct btrfs_device *dev = sblock->sdev->dev;
558540c1
JS		 347 struct btrfs_fs_info *fs_info = dev->dev_root->fs_info;
348 struct btrfs_path *path;
349 struct btrfs_key found_key;
350 struct extent_buffer *eb;
351 struct btrfs_extent_item *ei;
352 struct scrub_warning swarn;
353 u32 item_size;
354 int ret;
355 u64 ref_root;
356 u8 ref_level;
357 unsigned long ptr = 0;
358 const int bufsize = 4096;
4692cf58 359 u64 extent_item_pos;
558540c1
JS		 360
361 path = btrfs_alloc_path();
362
363 swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS);
364 swarn.msg_buf = kmalloc(bufsize, GFP_NOFS);
b5d67f64
SB		 365 BUG_ON(sblock->page_count < 1);
366 swarn.sector = (sblock->pagev[0].physical) >> 9;
367 swarn.logical = sblock->pagev[0].logical;
558540c1
JS		 368 swarn.errstr = errstr;
369 swarn.dev = dev;
370 swarn.msg_bufsize = bufsize;
371 swarn.scratch_bufsize = bufsize;
372
373 if (!path || !swarn.scratch_buf || !swarn.msg_buf)
374 goto out;
375
376 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key);
377 if (ret < 0)
378 goto out;
379
4692cf58 380 extent_item_pos = swarn.logical - found_key.objectid;
558540c1
JS		 381 swarn.extent_item_size = found_key.offset;
382
383 eb = path->nodes[0];
384 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
385 item_size = btrfs_item_size_nr(eb, path->slots[0]);
4692cf58 386 btrfs_release_path(path);
558540c1
JS		 387
388 if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
389 do {
390 ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
391 &ref_root, &ref_level);
1623edeb
SB		 392 printk(KERN_WARNING
393 "btrfs: %s at logical %llu on dev %s, "
558540c1
JS		 394 "sector %llu: metadata %s (level %d) in tree "
395 "%llu\n", errstr, swarn.logical, dev->name,
396 (unsigned long long)swarn.sector,
397 ref_level ? "node" : "leaf",
398 ret < 0 ? -1 : ref_level,
399 ret < 0 ? -1 : ref_root);
400 } while (ret != 1);
401 } else {
402 swarn.path = path;
7a3ae2f8
JS		 403 iterate_extent_inodes(fs_info, found_key.objectid,
404 extent_item_pos, 1,
558540c1
JS		 405 scrub_print_warning_inode, &swarn);
406 }
407
408out:
409 btrfs_free_path(path);
410 kfree(swarn.scratch_buf);
411 kfree(swarn.msg_buf);
412}
413
0ef8e451
JS		 414static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx)
415{
5da6fcbc 416 struct page *page = NULL;
0ef8e451
JS		 417 unsigned long index;
418 struct scrub_fixup_nodatasum *fixup = ctx;
419 int ret;
5da6fcbc 420 int corrected = 0;
0ef8e451 421 struct btrfs_key key;
5da6fcbc 422 struct inode *inode = NULL;
0ef8e451
JS		 423 u64 end = offset + PAGE_SIZE - 1;
424 struct btrfs_root *local_root;
425
426 key.objectid = root;
427 key.type = BTRFS_ROOT_ITEM_KEY;
428 key.offset = (u64)-1;
429 local_root = btrfs_read_fs_root_no_name(fixup->root->fs_info, &key);
430 if (IS_ERR(local_root))
431 return PTR_ERR(local_root);
432
433 key.type = BTRFS_INODE_ITEM_KEY;
434 key.objectid = inum;
435 key.offset = 0;
436 inode = btrfs_iget(fixup->root->fs_info->sb, &key, local_root, NULL);
437 if (IS_ERR(inode))
438 return PTR_ERR(inode);
439
0ef8e451
JS		 440 index = offset >> PAGE_CACHE_SHIFT;
441
442 page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
5da6fcbc
JS		 443 if (!page) {
444 ret = -ENOMEM;
445 goto out;
446 }
447
448 if (PageUptodate(page)) {
449 struct btrfs_mapping_tree *map_tree;
450 if (PageDirty(page)) {
451 /*
452 * we need to write the data to the defect sector. the
453 * data that was in that sector is not in memory,
454 * because the page was modified. we must not write the
455 * modified page to that sector.
456 *
457 * TODO: what could be done here: wait for the delalloc
458 * runner to write out that page (might involve
459 * COW) and see whether the sector is still
460 * referenced afterwards.
461 *
462 * For the meantime, we'll treat this error
463 * incorrectable, although there is a chance that a
464 * later scrub will find the bad sector again and that
465 * there's no dirty page in memory, then.
466 */
467 ret = -EIO;
468 goto out;
469 }
470 map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree;
471 ret = repair_io_failure(map_tree, offset, PAGE_SIZE,
472 fixup->logical, page,
473 fixup->mirror_num);
474 unlock_page(page);
475 corrected = !ret;
476 } else {
477 /*
478 * we need to get good data first. the general readpage path
479 * will call repair_io_failure for us, we just have to make
480 * sure we read the bad mirror.
481 */
482 ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
483 EXTENT_DAMAGED, GFP_NOFS);
484 if (ret) {
485 /* set_extent_bits should give proper error */
486 WARN_ON(ret > 0);
487 if (ret > 0)
488 ret = -EFAULT;
489 goto out;
490 }
491
492 ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page,
493 btrfs_get_extent,
494 fixup->mirror_num);
495 wait_on_page_locked(page);
496
497 corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset,
498 end, EXTENT_DAMAGED, 0, NULL);
499 if (!corrected)
500 clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end,
501 EXTENT_DAMAGED, GFP_NOFS);
502 }
503
504out:
505 if (page)
506 put_page(page);
507 if (inode)
508 iput(inode);
0ef8e451
JS		 509
510 if (ret < 0)
511 return ret;
512
513 if (ret == 0 && corrected) {
514 /*
515 * we only need to call readpage for one of the inodes belonging
516 * to this extent. so make iterate_extent_inodes stop
517 */
518 return 1;
519 }
520
521 return -EIO;
522}
523
524static void scrub_fixup_nodatasum(struct btrfs_work *work)
525{
526 int ret;
527 struct scrub_fixup_nodatasum *fixup;
528 struct scrub_dev *sdev;
529 struct btrfs_trans_handle *trans = NULL;
530 struct btrfs_fs_info *fs_info;
531 struct btrfs_path *path;
532 int uncorrectable = 0;
533
534 fixup = container_of(work, struct scrub_fixup_nodatasum, work);
535 sdev = fixup->sdev;
536 fs_info = fixup->root->fs_info;
537
538 path = btrfs_alloc_path();
539 if (!path) {
540 spin_lock(&sdev->stat_lock);
541 ++sdev->stat.malloc_errors;
542 spin_unlock(&sdev->stat_lock);
543 uncorrectable = 1;
544 goto out;
545 }
546
547 trans = btrfs_join_transaction(fixup->root);
548 if (IS_ERR(trans)) {
549 uncorrectable = 1;
550 goto out;
551 }
552
553 /*
554 * the idea is to trigger a regular read through the standard path. we
555 * read a page from the (failed) logical address by specifying the
556 * corresponding copynum of the failed sector. thus, that readpage is
557 * expected to fail.
558 * that is the point where on-the-fly error correction will kick in
559 * (once it's finished) and rewrite the failed sector if a good copy
560 * can be found.
561 */
562 ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info,
563 path, scrub_fixup_readpage,
564 fixup);
565 if (ret < 0) {
566 uncorrectable = 1;
567 goto out;
568 }
569 WARN_ON(ret != 1);
570
571 spin_lock(&sdev->stat_lock);
572 ++sdev->stat.corrected_errors;
573 spin_unlock(&sdev->stat_lock);
574
575out:
576 if (trans && !IS_ERR(trans))
577 btrfs_end_transaction(trans, fixup->root);
578 if (uncorrectable) {
579 spin_lock(&sdev->stat_lock);
580 ++sdev->stat.uncorrectable_errors;
581 spin_unlock(&sdev->stat_lock);
b5d67f64
SB		 582 printk_ratelimited(KERN_ERR
583 "btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
584 (unsigned long long)fixup->logical, sdev->dev->name);
0ef8e451
JS		 585 }
586
587 btrfs_free_path(path);
588 kfree(fixup);
589
590 /* see caller why we're pretending to be paused in the scrub counters */
591 mutex_lock(&fs_info->scrub_lock);
592 atomic_dec(&fs_info->scrubs_running);
593 atomic_dec(&fs_info->scrubs_paused);
594 mutex_unlock(&fs_info->scrub_lock);
595 atomic_dec(&sdev->fixup_cnt);
596 wake_up(&fs_info->scrub_pause_wait);
597 wake_up(&sdev->list_wait);
598}
599
a2de733c 600/*
b5d67f64
SB		 601 * scrub_handle_errored_block gets called when either verification of the
602 * pages failed or the bio failed to read, e.g. with EIO. In the latter
603 * case, this function handles all pages in the bio, even though only one
604 * may be bad.
605 * The goal of this function is to repair the errored block by using the
606 * contents of one of the mirrors.
a2de733c 607 */
b5d67f64 608static int scrub_handle_errored_block(struct scrub_block *sblock_to_check)
a2de733c 609{
b5d67f64
SB		 610 struct scrub_dev *sdev = sblock_to_check->sdev;
611 struct btrfs_fs_info *fs_info;
612 u64 length;
613 u64 logical;
614 u64 generation;
615 unsigned int failed_mirror_index;
616 unsigned int is_metadata;
617 unsigned int have_csum;
618 u8 *csum;
619 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */
620 struct scrub_block *sblock_bad;
621 int ret;
622 int mirror_index;
623 int page_num;
624 int success;
558540c1 625 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
b5d67f64
SB		 626 DEFAULT_RATELIMIT_BURST);
627
628 BUG_ON(sblock_to_check->page_count < 1);
629 fs_info = sdev->dev->dev_root->fs_info;
630 length = sblock_to_check->page_count * PAGE_SIZE;
631 logical = sblock_to_check->pagev[0].logical;
632 generation = sblock_to_check->pagev[0].generation;
633 BUG_ON(sblock_to_check->pagev[0].mirror_num < 1);
634 failed_mirror_index = sblock_to_check->pagev[0].mirror_num - 1;
635 is_metadata = !(sblock_to_check->pagev[0].flags &
636 BTRFS_EXTENT_FLAG_DATA);
637 have_csum = sblock_to_check->pagev[0].have_csum;
638 csum = sblock_to_check->pagev[0].csum;
13db62b7 639
b5d67f64
SB		 640 /*
641 * read all mirrors one after the other. This includes to
642 * re-read the extent or metadata block that failed (that was
643 * the cause that this fixup code is called) another time,
644 * page by page this time in order to know which pages
645 * caused I/O errors and which ones are good (for all mirrors).
646 * It is the goal to handle the situation when more than one
647 * mirror contains I/O errors, but the errors do not
648 * overlap, i.e. the data can be repaired by selecting the
649 * pages from those mirrors without I/O error on the
650 * particular pages. One example (with blocks >= 2 * PAGE_SIZE)
651 * would be that mirror #1 has an I/O error on the first page,
652 * the second page is good, and mirror #2 has an I/O error on
653 * the second page, but the first page is good.
654 * Then the first page of the first mirror can be repaired by
655 * taking the first page of the second mirror, and the
656 * second page of the second mirror can be repaired by
657 * copying the contents of the 2nd page of the 1st mirror.
658 * One more note: if the pages of one mirror contain I/O
659 * errors, the checksum cannot be verified. In order to get
660 * the best data for repairing, the first attempt is to find
661 * a mirror without I/O errors and with a validated checksum.
662 * Only if this is not possible, the pages are picked from
663 * mirrors with I/O errors without considering the checksum.
664 * If the latter is the case, at the end, the checksum of the
665 * repaired area is verified in order to correctly maintain
666 * the statistics.
667 */
668
669 sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS *
670 sizeof(*sblocks_for_recheck),
671 GFP_NOFS);
672 if (!sblocks_for_recheck) {
673 spin_lock(&sdev->stat_lock);
674 sdev->stat.malloc_errors++;
675 sdev->stat.read_errors++;
676 sdev->stat.uncorrectable_errors++;
677 spin_unlock(&sdev->stat_lock);
678 goto out;
a2de733c
AJ		 679 }
680
b5d67f64
SB		 681 /* setup the context, map the logical blocks and alloc the pages */
682 ret = scrub_setup_recheck_block(sdev, &fs_info->mapping_tree, length,
683 logical, sblocks_for_recheck);
684 if (ret) {
685 spin_lock(&sdev->stat_lock);
686 sdev->stat.read_errors++;
687 sdev->stat.uncorrectable_errors++;
688 spin_unlock(&sdev->stat_lock);
689 goto out;
690 }
691 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS);
692 sblock_bad = sblocks_for_recheck + failed_mirror_index;
13db62b7 693
b5d67f64
SB		 694 /* build and submit the bios for the failed mirror, check checksums */
695 ret = scrub_recheck_block(fs_info, sblock_bad, is_metadata, have_csum,
696 csum, generation, sdev->csum_size);
697 if (ret) {
698 spin_lock(&sdev->stat_lock);
699 sdev->stat.read_errors++;
700 sdev->stat.uncorrectable_errors++;
701 spin_unlock(&sdev->stat_lock);
702 goto out;
703 }
a2de733c 704
b5d67f64
SB		 705 if (!sblock_bad->header_error && !sblock_bad->checksum_error &&
706 sblock_bad->no_io_error_seen) {
707 /*
708 * the error disappeared after reading page by page, or
709 * the area was part of a huge bio and other parts of the
710 * bio caused I/O errors, or the block layer merged several
711 * read requests into one and the error is caused by a
712 * different bio (usually one of the two latter cases is
713 * the cause)
714 */
715 spin_lock(&sdev->stat_lock);
716 sdev->stat.unverified_errors++;
717 spin_unlock(&sdev->stat_lock);
a2de733c 718
b5d67f64 719 goto out;
a2de733c 720 }
a2de733c 721
b5d67f64
SB		 722 if (!sblock_bad->no_io_error_seen) {
723 spin_lock(&sdev->stat_lock);
724 sdev->stat.read_errors++;
725 spin_unlock(&sdev->stat_lock);
726 if (__ratelimit(&_rs))
727 scrub_print_warning("i/o error", sblock_to_check);
728 } else if (sblock_bad->checksum_error) {
729 spin_lock(&sdev->stat_lock);
730 sdev->stat.csum_errors++;
731 spin_unlock(&sdev->stat_lock);
732 if (__ratelimit(&_rs))
733 scrub_print_warning("checksum error", sblock_to_check);
734 } else if (sblock_bad->header_error) {
735 spin_lock(&sdev->stat_lock);
736 sdev->stat.verify_errors++;
737 spin_unlock(&sdev->stat_lock);
738 if (__ratelimit(&_rs))
739 scrub_print_warning("checksum/header error",
740 sblock_to_check);
741 }
a2de733c 742
b5d67f64
SB		 743 if (sdev->readonly)
744 goto did_not_correct_error;
745
746 if (!is_metadata && !have_csum) {
747 struct scrub_fixup_nodatasum *fixup_nodatasum;
a2de733c 748
b5d67f64
SB		 749 /*
750 * !is_metadata and !have_csum, this means that the data
751 * might not be COW'ed, that it might be modified
752 * concurrently. The general strategy to work on the
753 * commit root does not help in the case when COW is not
754 * used.
755 */
756 fixup_nodatasum = kzalloc(sizeof(*fixup_nodatasum), GFP_NOFS);
757 if (!fixup_nodatasum)
758 goto did_not_correct_error;
759 fixup_nodatasum->sdev = sdev;
760 fixup_nodatasum->logical = logical;
761 fixup_nodatasum->root = fs_info->extent_root;
762 fixup_nodatasum->mirror_num = failed_mirror_index + 1;
a2de733c 763 /*
0ef8e451
JS		 764 * increment scrubs_running to prevent cancel requests from
765 * completing as long as a fixup worker is running. we must also
766 * increment scrubs_paused to prevent deadlocking on pause
767 * requests used for transactions commits (as the worker uses a
768 * transaction context). it is safe to regard the fixup worker
769 * as paused for all matters practical. effectively, we only
770 * avoid cancellation requests from completing.
a2de733c 771 */
0ef8e451
JS		 772 mutex_lock(&fs_info->scrub_lock);
773 atomic_inc(&fs_info->scrubs_running);
774 atomic_inc(&fs_info->scrubs_paused);
775 mutex_unlock(&fs_info->scrub_lock);
776 atomic_inc(&sdev->fixup_cnt);
b5d67f64
SB		 777 fixup_nodatasum->work.func = scrub_fixup_nodatasum;
778 btrfs_queue_worker(&fs_info->scrub_workers,
779 &fixup_nodatasum->work);
780 goto out;
a2de733c
AJ		 781 }
782
b5d67f64
SB		 783 /*
784 * now build and submit the bios for the other mirrors, check
785 * checksums
786 */
787 for (mirror_index = 0;
788 mirror_index < BTRFS_MAX_MIRRORS &&
789 sblocks_for_recheck[mirror_index].page_count > 0;
790 mirror_index++) {
791 if (mirror_index == failed_mirror_index)
792 continue;
793
794 /* build and submit the bios, check checksums */
795 ret = scrub_recheck_block(fs_info,
796 sblocks_for_recheck + mirror_index,
797 is_metadata, have_csum, csum,
798 generation, sdev->csum_size);
799 if (ret)
800 goto did_not_correct_error;
a2de733c
AJ		 801 }
802
b5d67f64
SB		 803 /*
804 * first try to pick the mirror which is completely without I/O
805 * errors and also does not have a checksum error.
806 * If one is found, and if a checksum is present, the full block
807 * that is known to contain an error is rewritten. Afterwards
808 * the block is known to be corrected.
809 * If a mirror is found which is completely correct, and no
810 * checksum is present, only those pages are rewritten that had
811 * an I/O error in the block to be repaired, since it cannot be
812 * determined, which copy of the other pages is better (and it
813 * could happen otherwise that a correct page would be
814 * overwritten by a bad one).
815 */
816 for (mirror_index = 0;
817 mirror_index < BTRFS_MAX_MIRRORS &&
818 sblocks_for_recheck[mirror_index].page_count > 0;
819 mirror_index++) {
820 struct scrub_block *sblock_other = sblocks_for_recheck +
821 mirror_index;
822
823 if (!sblock_other->header_error &&
824 !sblock_other->checksum_error &&
825 sblock_other->no_io_error_seen) {
826 int force_write = is_metadata || have_csum;
827
828 ret = scrub_repair_block_from_good_copy(sblock_bad,
829 sblock_other,
830 force_write);
831 if (0 == ret)
832 goto corrected_error;
833 }
834 }
a2de733c
AJ		 835
836 /*
b5d67f64
SB		 837 * in case of I/O errors in the area that is supposed to be
838 * repaired, continue by picking good copies of those pages.
839 * Select the good pages from mirrors to rewrite bad pages from
840 * the area to fix. Afterwards verify the checksum of the block
841 * that is supposed to be repaired. This verification step is
842 * only done for the purpose of statistic counting and for the
843 * final scrub report, whether errors remain.
844 * A perfect algorithm could make use of the checksum and try
845 * all possible combinations of pages from the different mirrors
846 * until the checksum verification succeeds. For example, when
847 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page
848 * of mirror #2 is readable but the final checksum test fails,
849 * then the 2nd page of mirror #3 could be tried, whether now
850 * the final checksum succeedes. But this would be a rare
851 * exception and is therefore not implemented. At least it is
852 * avoided that the good copy is overwritten.
853 * A more useful improvement would be to pick the sectors
854 * without I/O error based on sector sizes (512 bytes on legacy
855 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one
856 * mirror could be repaired by taking 512 byte of a different
857 * mirror, even if other 512 byte sectors in the same PAGE_SIZE
858 * area are unreadable.
a2de733c 859 */
a2de733c 860
b5d67f64
SB		 861 /* can only fix I/O errors from here on */
862 if (sblock_bad->no_io_error_seen)
863 goto did_not_correct_error;
864
865 success = 1;
866 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
867 struct scrub_page *page_bad = sblock_bad->pagev + page_num;
868
869 if (!page_bad->io_error)
a2de733c 870 continue;
b5d67f64
SB		 871
872 for (mirror_index = 0;
873 mirror_index < BTRFS_MAX_MIRRORS &&
874 sblocks_for_recheck[mirror_index].page_count > 0;
875 mirror_index++) {
876 struct scrub_block *sblock_other = sblocks_for_recheck +
877 mirror_index;
878 struct scrub_page *page_other = sblock_other->pagev +
879 page_num;
880
881 if (!page_other->io_error) {
882 ret = scrub_repair_page_from_good_copy(
883 sblock_bad, sblock_other, page_num, 0);
884 if (0 == ret) {
885 page_bad->io_error = 0;
886 break; /* succeeded for this page */
887 }
888 }
96e36920 889 }
a2de733c 890
b5d67f64
SB		 891 if (page_bad->io_error) {
892 /* did not find a mirror to copy the page from */
893 success = 0;
894 }
a2de733c 895 }
a2de733c 896
b5d67f64
SB		 897 if (success) {
898 if (is_metadata || have_csum) {
899 /*
900 * need to verify the checksum now that all
901 * sectors on disk are repaired (the write
902 * request for data to be repaired is on its way).
903 * Just be lazy and use scrub_recheck_block()
904 * which re-reads the data before the checksum
905 * is verified, but most likely the data comes out
906 * of the page cache.
907 */
908 ret = scrub_recheck_block(fs_info, sblock_bad,
909 is_metadata, have_csum, csum,
910 generation, sdev->csum_size);
911 if (!ret && !sblock_bad->header_error &&
912 !sblock_bad->checksum_error &&
913 sblock_bad->no_io_error_seen)
914 goto corrected_error;
915 else
916 goto did_not_correct_error;
917 } else {
918corrected_error:
919 spin_lock(&sdev->stat_lock);
920 sdev->stat.corrected_errors++;
921 spin_unlock(&sdev->stat_lock);
922 printk_ratelimited(KERN_ERR
923 "btrfs: fixed up error at logical %llu on dev %s\n",
924 (unsigned long long)logical, sdev->dev->name);
8628764e 925 }
b5d67f64
SB		 926 } else {
927did_not_correct_error:
928 spin_lock(&sdev->stat_lock);
929 sdev->stat.uncorrectable_errors++;
930 spin_unlock(&sdev->stat_lock);
931 printk_ratelimited(KERN_ERR
932 "btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
933 (unsigned long long)logical, sdev->dev->name);
96e36920 934 }
a2de733c 935
b5d67f64
SB		 936out:
937 if (sblocks_for_recheck) {
938 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS;
939 mirror_index++) {
940 struct scrub_block *sblock = sblocks_for_recheck +
941 mirror_index;
942 int page_index;
943
944 for (page_index = 0; page_index < SCRUB_PAGES_PER_BIO;
945 page_index++)
946 if (sblock->pagev[page_index].page)
947 __free_page(
948 sblock->pagev[page_index].page);
949 }
950 kfree(sblocks_for_recheck);
951 }
a2de733c 952
b5d67f64
SB		 953 return 0;
954}
a2de733c 955
b5d67f64
SB		 956static int scrub_setup_recheck_block(struct scrub_dev *sdev,
957 struct btrfs_mapping_tree *map_tree,
958 u64 length, u64 logical,
959 struct scrub_block *sblocks_for_recheck)
960{
961 int page_index;
962 int mirror_index;
963 int ret;
964
965 /*
966 * note: the three members sdev, ref_count and outstanding_pages
967 * are not used (and not set) in the blocks that are used for
968 * the recheck procedure
969 */
970
971 page_index = 0;
972 while (length > 0) {
973 u64 sublen = min_t(u64, length, PAGE_SIZE);
974 u64 mapped_length = sublen;
975 struct btrfs_bio *bbio = NULL;
a2de733c 976
b5d67f64
SB		 977 /*
978 * with a length of PAGE_SIZE, each returned stripe
979 * represents one mirror
980 */
981 ret = btrfs_map_block(map_tree, WRITE, logical, &mapped_length,
982 &bbio, 0);
983 if (ret || !bbio || mapped_length < sublen) {
984 kfree(bbio);
985 return -EIO;
986 }
987
988 BUG_ON(page_index >= SCRUB_PAGES_PER_BIO);
989 for (mirror_index = 0; mirror_index < (int)bbio->num_stripes;
990 mirror_index++) {
991 struct scrub_block *sblock;
992 struct scrub_page *page;
993
994 if (mirror_index >= BTRFS_MAX_MIRRORS)
995 continue;
996
997 sblock = sblocks_for_recheck + mirror_index;
998 page = sblock->pagev + page_index;
999 page->logical = logical;
1000 page->physical = bbio->stripes[mirror_index].physical;
1001 page->bdev = bbio->stripes[mirror_index].dev->bdev;
1002 page->mirror_num = mirror_index + 1;
1003 page->page = alloc_page(GFP_NOFS);
1004 if (!page->page) {
1005 spin_lock(&sdev->stat_lock);
1006 sdev->stat.malloc_errors++;
1007 spin_unlock(&sdev->stat_lock);
1008 return -ENOMEM;
1009 }
1010 sblock->page_count++;
1011 }
1012 kfree(bbio);
1013 length -= sublen;
1014 logical += sublen;
1015 page_index++;
1016 }
1017
1018 return 0;
96e36920
ID		 1019}
1020
b5d67f64
SB		 1021/*
1022 * this function will check the on disk data for checksum errors, header
1023 * errors and read I/O errors. If any I/O errors happen, the exact pages
1024 * which are errored are marked as being bad. The goal is to enable scrub
1025 * to take those pages that are not errored from all the mirrors so that
1026 * the pages that are errored in the just handled mirror can be repaired.
1027 */
1028static int scrub_recheck_block(struct btrfs_fs_info *fs_info,
1029 struct scrub_block *sblock, int is_metadata,
1030 int have_csum, u8 *csum, u64 generation,
1031 u16 csum_size)
96e36920 1032{
b5d67f64 1033 int page_num;
96e36920 1034
b5d67f64
SB		 1035 sblock->no_io_error_seen = 1;
1036 sblock->header_error = 0;
1037 sblock->checksum_error = 0;
96e36920 1038
b5d67f64
SB		 1039 for (page_num = 0; page_num < sblock->page_count; page_num++) {
1040 struct bio *bio;
1041 int ret;
1042 struct scrub_page *page = sblock->pagev + page_num;
1043 DECLARE_COMPLETION_ONSTACK(complete);
1044
1045 BUG_ON(!page->page);
1046 bio = bio_alloc(GFP_NOFS, 1);
1047 bio->bi_bdev = page->bdev;
1048 bio->bi_sector = page->physical >> 9;
1049 bio->bi_end_io = scrub_complete_bio_end_io;
1050 bio->bi_private = &complete;
1051
1052 ret = bio_add_page(bio, page->page, PAGE_SIZE, 0);
1053 if (PAGE_SIZE != ret) {
1054 bio_put(bio);
1055 return -EIO;
1056 }
1057 btrfsic_submit_bio(READ, bio);
96e36920 1058
b5d67f64
SB		 1059 /* this will also unplug the queue */
1060 wait_for_completion(&complete);
1061
1062 page->io_error = !test_bit(BIO_UPTODATE, &bio->bi_flags);
1063 if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
1064 sblock->no_io_error_seen = 0;
1065 bio_put(bio);
1066 }
1067
1068 if (sblock->no_io_error_seen)
1069 scrub_recheck_block_checksum(fs_info, sblock, is_metadata,
1070 have_csum, csum, generation,
1071 csum_size);
1072
1073 return 0;
a2de733c
AJ		 1074}
1075
b5d67f64
SB		 1076static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info,
1077 struct scrub_block *sblock,
1078 int is_metadata, int have_csum,
1079 const u8 *csum, u64 generation,
1080 u16 csum_size)
a2de733c 1081{
b5d67f64
SB		 1082 int page_num;
1083 u8 calculated_csum[BTRFS_CSUM_SIZE];
1084 u32 crc = ~(u32)0;
1085 struct btrfs_root *root = fs_info->extent_root;
1086 void *mapped_buffer;
1087
1088 BUG_ON(!sblock->pagev[0].page);
1089 if (is_metadata) {
1090 struct btrfs_header *h;
1091
1092 mapped_buffer = kmap_atomic(sblock->pagev[0].page, KM_USER0);
1093 h = (struct btrfs_header *)mapped_buffer;
1094
1095 if (sblock->pagev[0].logical != le64_to_cpu(h->bytenr) ||
1096 generation != le64_to_cpu(h->generation) ||
1097 memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE) ||
1098 memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1099 BTRFS_UUID_SIZE))
1100 sblock->header_error = 1;
1101 csum = h->csum;
1102 } else {
1103 if (!have_csum)
1104 return;
a2de733c 1105
b5d67f64
SB		 1106 mapped_buffer = kmap_atomic(sblock->pagev[0].page, KM_USER0);
1107 }
a2de733c 1108
b5d67f64
SB		 1109 for (page_num = 0;;) {
1110 if (page_num == 0 && is_metadata)
1111 crc = btrfs_csum_data(root,
1112 ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE,
1113 crc, PAGE_SIZE - BTRFS_CSUM_SIZE);
1114 else
1115 crc = btrfs_csum_data(root, mapped_buffer, crc,
1116 PAGE_SIZE);
1117
1118 kunmap_atomic(mapped_buffer, KM_USER0);
1119 page_num++;
1120 if (page_num >= sblock->page_count)
1121 break;
1122 BUG_ON(!sblock->pagev[page_num].page);
1123
1124 mapped_buffer = kmap_atomic(sblock->pagev[page_num].page,
1125 KM_USER0);
1126 }
1127
1128 btrfs_csum_final(crc, calculated_csum);
1129 if (memcmp(calculated_csum, csum, csum_size))
1130 sblock->checksum_error = 1;
a2de733c
AJ		 1131}
1132
b5d67f64 1133static void scrub_complete_bio_end_io(struct bio *bio, int err)
a2de733c 1134{
b5d67f64
SB		 1135 complete((struct completion *)bio->bi_private);
1136}
a2de733c 1137
b5d67f64
SB		 1138static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad,
1139 struct scrub_block *sblock_good,
1140 int force_write)
1141{
1142 int page_num;
1143 int ret = 0;
96e36920 1144
b5d67f64
SB		 1145 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) {
1146 int ret_sub;
96e36920 1147
b5d67f64
SB		 1148 ret_sub = scrub_repair_page_from_good_copy(sblock_bad,
1149 sblock_good,
1150 page_num,
1151 force_write);
1152 if (ret_sub)
1153 ret = ret_sub;
a2de733c 1154 }
b5d67f64
SB		 1155
1156 return ret;
1157}
1158
1159static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
1160 struct scrub_block *sblock_good,
1161 int page_num, int force_write)
1162{
1163 struct scrub_page *page_bad = sblock_bad->pagev + page_num;
1164 struct scrub_page *page_good = sblock_good->pagev + page_num;
1165
1166 BUG_ON(sblock_bad->pagev[page_num].page == NULL);
1167 BUG_ON(sblock_good->pagev[page_num].page == NULL);
1168 if (force_write || sblock_bad->header_error ||
1169 sblock_bad->checksum_error || page_bad->io_error) {
1170 struct bio *bio;
1171 int ret;
1172 DECLARE_COMPLETION_ONSTACK(complete);
1173
1174 bio = bio_alloc(GFP_NOFS, 1);
1175 bio->bi_bdev = page_bad->bdev;
1176 bio->bi_sector = page_bad->physical >> 9;
1177 bio->bi_end_io = scrub_complete_bio_end_io;
1178 bio->bi_private = &complete;
1179
1180 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0);
1181 if (PAGE_SIZE != ret) {
1182 bio_put(bio);
1183 return -EIO;
13db62b7 1184 }
b5d67f64
SB		 1185 btrfsic_submit_bio(WRITE, bio);
1186
1187 /* this will also unplug the queue */
1188 wait_for_completion(&complete);
1189 bio_put(bio);
a2de733c
AJ		 1190 }
1191
b5d67f64
SB		 1192 return 0;
1193}
1194
1195static void scrub_checksum(struct scrub_block *sblock)
1196{
1197 u64 flags;
1198 int ret;
1199
1200 BUG_ON(sblock->page_count < 1);
1201 flags = sblock->pagev[0].flags;
1202 ret = 0;
1203 if (flags & BTRFS_EXTENT_FLAG_DATA)
1204 ret = scrub_checksum_data(sblock);
1205 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
1206 ret = scrub_checksum_tree_block(sblock);
1207 else if (flags & BTRFS_EXTENT_FLAG_SUPER)
1208 (void)scrub_checksum_super(sblock);
1209 else
1210 WARN_ON(1);
1211 if (ret)
1212 scrub_handle_errored_block(sblock);
a2de733c
AJ		 1213}
1214
b5d67f64 1215static int scrub_checksum_data(struct scrub_block *sblock)
a2de733c 1216{
b5d67f64 1217 struct scrub_dev *sdev = sblock->sdev;
a2de733c 1218 u8 csum[BTRFS_CSUM_SIZE];
b5d67f64
SB		 1219 u8 *on_disk_csum;
1220 struct page *page;
1221 void *buffer;
a2de733c
AJ		 1222 u32 crc = ~(u32)0;
1223 int fail = 0;
1224 struct btrfs_root *root = sdev->dev->dev_root;
b5d67f64
SB		 1225 u64 len;
1226 int index;
a2de733c 1227
b5d67f64
SB		 1228 BUG_ON(sblock->page_count < 1);
1229 if (!sblock->pagev[0].have_csum)
a2de733c
AJ		 1230 return 0;
1231
b5d67f64
SB		 1232 on_disk_csum = sblock->pagev[0].csum;
1233 page = sblock->pagev[0].page;
1234 buffer = kmap_atomic(page, KM_USER0);
1235
1236 len = sdev->sectorsize;
1237 index = 0;
1238 for (;;) {
1239 u64 l = min_t(u64, len, PAGE_SIZE);
1240
1241 crc = btrfs_csum_data(root, buffer, crc, l);
1242 kunmap_atomic(buffer, KM_USER0);
1243 len -= l;
1244 if (len == 0)
1245 break;
1246 index++;
1247 BUG_ON(index >= sblock->page_count);
1248 BUG_ON(!sblock->pagev[index].page);
1249 page = sblock->pagev[index].page;
1250 buffer = kmap_atomic(page, KM_USER0);
1251 }
1252
a2de733c 1253 btrfs_csum_final(crc, csum);
b5d67f64 1254 if (memcmp(csum, on_disk_csum, sdev->csum_size))
a2de733c
AJ		 1255 fail = 1;
1256
b5d67f64
SB		 1257 if (fail) {
1258 spin_lock(&sdev->stat_lock);
a2de733c 1259 ++sdev->stat.csum_errors;
b5d67f64
SB		 1260 spin_unlock(&sdev->stat_lock);
1261 }
a2de733c
AJ		 1262
1263 return fail;
1264}
1265
b5d67f64 1266static int scrub_checksum_tree_block(struct scrub_block *sblock)
a2de733c 1267{
b5d67f64 1268 struct scrub_dev *sdev = sblock->sdev;
a2de733c
AJ		 1269 struct btrfs_header *h;
1270 struct btrfs_root *root = sdev->dev->dev_root;
1271 struct btrfs_fs_info *fs_info = root->fs_info;
b5d67f64
SB		 1272 u8 calculated_csum[BTRFS_CSUM_SIZE];
1273 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1274 struct page *page;
1275 void *mapped_buffer;
1276 u64 mapped_size;
1277 void *p;
a2de733c
AJ		 1278 u32 crc = ~(u32)0;
1279 int fail = 0;
1280 int crc_fail = 0;
b5d67f64
SB		 1281 u64 len;
1282 int index;
1283
1284 BUG_ON(sblock->page_count < 1);
1285 page = sblock->pagev[0].page;
1286 mapped_buffer = kmap_atomic(page, KM_USER0);
1287 h = (struct btrfs_header *)mapped_buffer;
1288 memcpy(on_disk_csum, h->csum, sdev->csum_size);
a2de733c
AJ		 1289
1290 /*
1291 * we don't use the getter functions here, as we
1292 * a) don't have an extent buffer and
1293 * b) the page is already kmapped
1294 */
a2de733c 1295
b5d67f64 1296 if (sblock->pagev[0].logical != le64_to_cpu(h->bytenr))
a2de733c
AJ		 1297 ++fail;
1298
b5d67f64 1299 if (sblock->pagev[0].generation != le64_to_cpu(h->generation))
a2de733c
AJ		 1300 ++fail;
1301
1302 if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1303 ++fail;
1304
1305 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid,
1306 BTRFS_UUID_SIZE))
1307 ++fail;
1308
b5d67f64
SB		 1309 BUG_ON(sdev->nodesize != sdev->leafsize);
1310 len = sdev->nodesize - BTRFS_CSUM_SIZE;
1311 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1312 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1313 index = 0;
1314 for (;;) {
1315 u64 l = min_t(u64, len, mapped_size);
1316
1317 crc = btrfs_csum_data(root, p, crc, l);
1318 kunmap_atomic(mapped_buffer, KM_USER0);
1319 len -= l;
1320 if (len == 0)
1321 break;
1322 index++;
1323 BUG_ON(index >= sblock->page_count);
1324 BUG_ON(!sblock->pagev[index].page);
1325 page = sblock->pagev[index].page;
1326 mapped_buffer = kmap_atomic(page, KM_USER0);
1327 mapped_size = PAGE_SIZE;
1328 p = mapped_buffer;
1329 }
1330
1331 btrfs_csum_final(crc, calculated_csum);
1332 if (memcmp(calculated_csum, on_disk_csum, sdev->csum_size))
a2de733c
AJ		 1333 ++crc_fail;
1334
b5d67f64
SB		 1335 if (crc_fail || fail) {
1336 spin_lock(&sdev->stat_lock);
1337 if (crc_fail)
1338 ++sdev->stat.csum_errors;
1339 if (fail)
1340 ++sdev->stat.verify_errors;
1341 spin_unlock(&sdev->stat_lock);
1342 }
a2de733c
AJ		 1343
1344 return fail || crc_fail;
1345}
1346
b5d67f64 1347static int scrub_checksum_super(struct scrub_block *sblock)
a2de733c
AJ		 1348{
1349 struct btrfs_super_block *s;
b5d67f64 1350 struct scrub_dev *sdev = sblock->sdev;
a2de733c
AJ		 1351 struct btrfs_root *root = sdev->dev->dev_root;
1352 struct btrfs_fs_info *fs_info = root->fs_info;
b5d67f64
SB		 1353 u8 calculated_csum[BTRFS_CSUM_SIZE];
1354 u8 on_disk_csum[BTRFS_CSUM_SIZE];
1355 struct page *page;
1356 void *mapped_buffer;
1357 u64 mapped_size;
1358 void *p;
a2de733c
AJ		 1359 u32 crc = ~(u32)0;
1360 int fail = 0;
b5d67f64
SB		 1361 u64 len;
1362 int index;
a2de733c 1363
b5d67f64
SB		 1364 BUG_ON(sblock->page_count < 1);
1365 page = sblock->pagev[0].page;
1366 mapped_buffer = kmap_atomic(page, KM_USER0);
1367 s = (struct btrfs_super_block *)mapped_buffer;
1368 memcpy(on_disk_csum, s->csum, sdev->csum_size);
a2de733c 1369
b5d67f64 1370 if (sblock->pagev[0].logical != le64_to_cpu(s->bytenr))
a2de733c
AJ		 1371 ++fail;
1372
b5d67f64 1373 if (sblock->pagev[0].generation != le64_to_cpu(s->generation))
a2de733c
AJ		 1374 ++fail;
1375
1376 if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE))
1377 ++fail;
1378
b5d67f64
SB		 1379 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE;
1380 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE;
1381 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE;
1382 index = 0;
1383 for (;;) {
1384 u64 l = min_t(u64, len, mapped_size);
1385
1386 crc = btrfs_csum_data(root, p, crc, l);
1387 kunmap_atomic(mapped_buffer, KM_USER0);
1388 len -= l;
1389 if (len == 0)
1390 break;
1391 index++;
1392 BUG_ON(index >= sblock->page_count);
1393 BUG_ON(!sblock->pagev[index].page);
1394 page = sblock->pagev[index].page;
1395 mapped_buffer = kmap_atomic(page, KM_USER0);
1396 mapped_size = PAGE_SIZE;
1397 p = mapped_buffer;
1398 }
1399
1400 btrfs_csum_final(crc, calculated_csum);
1401 if (memcmp(calculated_csum, on_disk_csum, sdev->csum_size))
a2de733c
AJ		 1402 ++fail;
1403
1404 if (fail) {
1405 /*
1406 * if we find an error in a super block, we just report it.
1407 * They will get written with the next transaction commit
1408 * anyway
1409 */
1410 spin_lock(&sdev->stat_lock);
1411 ++sdev->stat.super_errors;
1412 spin_unlock(&sdev->stat_lock);
1413 }
1414
1415 return fail;
1416}
1417
b5d67f64
SB		 1418static void scrub_block_get(struct scrub_block *sblock)
1419{
1420 atomic_inc(&sblock->ref_count);
1421}
1422
1423static void scrub_block_put(struct scrub_block *sblock)
1424{
1425 if (atomic_dec_and_test(&sblock->ref_count)) {
1426 int i;
1427
1428 for (i = 0; i < sblock->page_count; i++)
1429 if (sblock->pagev[i].page)
1430 __free_page(sblock->pagev[i].page);
1431 kfree(sblock);
1432 }
1433}
1434
1623edeb 1435static void scrub_submit(struct scrub_dev *sdev)
a2de733c
AJ		 1436{
1437 struct scrub_bio *sbio;
1438
1439 if (sdev->curr == -1)
1623edeb 1440 return;
a2de733c
AJ		 1441
1442 sbio = sdev->bios[sdev->curr];
a2de733c
AJ		 1443 sdev->curr = -1;
1444 atomic_inc(&sdev->in_flight);
1445
21adbd5c 1446 btrfsic_submit_bio(READ, sbio->bio);
a2de733c
AJ		 1447}
1448
b5d67f64
SB		 1449static int scrub_add_page_to_bio(struct scrub_dev *sdev,
1450 struct scrub_page *spage)
a2de733c 1451{
b5d67f64 1452 struct scrub_block *sblock = spage->sblock;
a2de733c 1453 struct scrub_bio *sbio;
69f4cb52 1454 int ret;
a2de733c
AJ		 1455
1456again:
1457 /*
1458 * grab a fresh bio or wait for one to become available
1459 */
1460 while (sdev->curr == -1) {
1461 spin_lock(&sdev->list_lock);
1462 sdev->curr = sdev->first_free;
1463 if (sdev->curr != -1) {
1464 sdev->first_free = sdev->bios[sdev->curr]->next_free;
1465 sdev->bios[sdev->curr]->next_free = -1;
b5d67f64 1466 sdev->bios[sdev->curr]->page_count = 0;
a2de733c
AJ		 1467 spin_unlock(&sdev->list_lock);
1468 } else {
1469 spin_unlock(&sdev->list_lock);
1470 wait_event(sdev->list_wait, sdev->first_free != -1);
1471 }
1472 }
1473 sbio = sdev->bios[sdev->curr];
b5d67f64 1474 if (sbio->page_count == 0) {
69f4cb52
AJ		 1475 struct bio *bio;
1476
b5d67f64
SB		 1477 sbio->physical = spage->physical;
1478 sbio->logical = spage->logical;
1479 bio = sbio->bio;
1480 if (!bio) {
1481 bio = bio_alloc(GFP_NOFS, sdev->pages_per_bio);
1482 if (!bio)
1483 return -ENOMEM;
1484 sbio->bio = bio;
1485 }
69f4cb52
AJ		 1486
1487 bio->bi_private = sbio;
1488 bio->bi_end_io = scrub_bio_end_io;
1489 bio->bi_bdev = sdev->dev->bdev;
b5d67f64 1490 bio->bi_sector = spage->physical >> 9;
69f4cb52 1491 sbio->err = 0;
b5d67f64
SB		 1492 } else if (sbio->physical + sbio->page_count * PAGE_SIZE !=
1493 spage->physical ||
1494 sbio->logical + sbio->page_count * PAGE_SIZE !=
1495 spage->logical) {
1623edeb 1496 scrub_submit(sdev);
a2de733c
AJ		 1497 goto again;
1498 }
69f4cb52 1499
b5d67f64
SB		 1500 sbio->pagev[sbio->page_count] = spage;
1501 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0);
1502 if (ret != PAGE_SIZE) {
1503 if (sbio->page_count < 1) {
1504 bio_put(sbio->bio);
1505 sbio->bio = NULL;
1506 return -EIO;
1507 }
1623edeb 1508 scrub_submit(sdev);
69f4cb52
AJ		 1509 goto again;
1510 }
1511
b5d67f64
SB		 1512 scrub_block_get(sblock); /* one for the added page */
1513 atomic_inc(&sblock->outstanding_pages);
1514 sbio->page_count++;
1515 if (sbio->page_count == sdev->pages_per_bio)
1516 scrub_submit(sdev);
1517
1518 return 0;
1519}
1520
1521static int scrub_pages(struct scrub_dev *sdev, u64 logical, u64 len,
1522 u64 physical, u64 flags, u64 gen, int mirror_num,
1523 u8 *csum, int force)
1524{
1525 struct scrub_block *sblock;
1526 int index;
1527
1528 sblock = kzalloc(sizeof(*sblock), GFP_NOFS);
1529 if (!sblock) {
1530 spin_lock(&sdev->stat_lock);
1531 sdev->stat.malloc_errors++;
1532 spin_unlock(&sdev->stat_lock);
1533 return -ENOMEM;
1534 }
1535
1536 /* one ref inside this function, plus one for each page later on */
1537 atomic_set(&sblock->ref_count, 1);
1538 sblock->sdev = sdev;
1539 sblock->no_io_error_seen = 1;
1540
1541 for (index = 0; len > 0; index++) {
1542 struct scrub_page *spage = sblock->pagev + index;
1543 u64 l = min_t(u64, len, PAGE_SIZE);
1544
1545 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK);
1546 spage->page = alloc_page(GFP_NOFS);
1547 if (!spage->page) {
1548 spin_lock(&sdev->stat_lock);
1549 sdev->stat.malloc_errors++;
1550 spin_unlock(&sdev->stat_lock);
1551 while (index > 0) {
1552 index--;
1553 __free_page(sblock->pagev[index].page);
1554 }
1555 kfree(sblock);
1556 return -ENOMEM;
1557 }
1558 spage->sblock = sblock;
1559 spage->bdev = sdev->dev->bdev;
1560 spage->flags = flags;
1561 spage->generation = gen;
1562 spage->logical = logical;
1563 spage->physical = physical;
1564 spage->mirror_num = mirror_num;
1565 if (csum) {
1566 spage->have_csum = 1;
1567 memcpy(spage->csum, csum, sdev->csum_size);
1568 } else {
1569 spage->have_csum = 0;
1570 }
1571 sblock->page_count++;
1572 len -= l;
1573 logical += l;
1574 physical += l;
1575 }
1576
1577 BUG_ON(sblock->page_count == 0);
1578 for (index = 0; index < sblock->page_count; index++) {
1579 struct scrub_page *spage = sblock->pagev + index;
1580 int ret;
1581
1582 ret = scrub_add_page_to_bio(sdev, spage);
1583 if (ret) {
1584 scrub_block_put(sblock);
1585 return ret;
1586 }
a2de733c 1587 }
b5d67f64
SB		 1588
1589 if (force)
1623edeb 1590 scrub_submit(sdev);
a2de733c 1591
b5d67f64
SB		 1592 /* last one frees, either here or in bio completion for last page */
1593 scrub_block_put(sblock);
a2de733c
AJ		 1594 return 0;
1595}
1596
b5d67f64
SB		 1597static void scrub_bio_end_io(struct bio *bio, int err)
1598{
1599 struct scrub_bio *sbio = bio->bi_private;
1600 struct scrub_dev *sdev = sbio->sdev;
1601 struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info;
1602
1603 sbio->err = err;
1604 sbio->bio = bio;
1605
1606 btrfs_queue_worker(&fs_info->scrub_workers, &sbio->work);
1607}
1608
1609static void scrub_bio_end_io_worker(struct btrfs_work *work)
1610{
1611 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work);
1612 struct scrub_dev *sdev = sbio->sdev;
1613 int i;
1614
1615 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_BIO);
1616 if (sbio->err) {
1617 for (i = 0; i < sbio->page_count; i++) {
1618 struct scrub_page *spage = sbio->pagev[i];
1619
1620 spage->io_error = 1;
1621 spage->sblock->no_io_error_seen = 0;
1622 }
1623 }
1624
1625 /* now complete the scrub_block items that have all pages completed */
1626 for (i = 0; i < sbio->page_count; i++) {
1627 struct scrub_page *spage = sbio->pagev[i];
1628 struct scrub_block *sblock = spage->sblock;
1629
1630 if (atomic_dec_and_test(&sblock->outstanding_pages))
1631 scrub_block_complete(sblock);
1632 scrub_block_put(sblock);
1633 }
1634
1635 if (sbio->err) {
1636 /* what is this good for??? */
1637 sbio->bio->bi_flags &= ~(BIO_POOL_MASK - 1);
1638 sbio->bio->bi_flags |= 1 << BIO_UPTODATE;
1639 sbio->bio->bi_phys_segments = 0;
1640 sbio->bio->bi_idx = 0;
1641
1642 for (i = 0; i < sbio->page_count; i++) {
1643 struct bio_vec *bi;
1644 bi = &sbio->bio->bi_io_vec[i];
1645 bi->bv_offset = 0;
1646 bi->bv_len = PAGE_SIZE;
1647 }
1648 }
1649
1650 bio_put(sbio->bio);
1651 sbio->bio = NULL;
1652 spin_lock(&sdev->list_lock);
1653 sbio->next_free = sdev->first_free;
1654 sdev->first_free = sbio->index;
1655 spin_unlock(&sdev->list_lock);
1656 atomic_dec(&sdev->in_flight);
1657 wake_up(&sdev->list_wait);
1658}
1659
1660static void scrub_block_complete(struct scrub_block *sblock)
1661{
1662 if (!sblock->no_io_error_seen)
1663 scrub_handle_errored_block(sblock);
1664 else
1665 scrub_checksum(sblock);
1666}
1667
a2de733c
AJ		 1668static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len,
1669 u8 *csum)
1670{
1671 struct btrfs_ordered_sum *sum = NULL;
1672 int ret = 0;
1673 unsigned long i;
1674 unsigned long num_sectors;
a2de733c
AJ		 1675
1676 while (!list_empty(&sdev->csum_list)) {
1677 sum = list_first_entry(&sdev->csum_list,
1678 struct btrfs_ordered_sum, list);
1679 if (sum->bytenr > logical)
1680 return 0;
1681 if (sum->bytenr + sum->len > logical)
1682 break;
1683
1684 ++sdev->stat.csum_discards;
1685 list_del(&sum->list);
1686 kfree(sum);
1687 sum = NULL;
1688 }
1689 if (!sum)
1690 return 0;
1691
b5d67f64 1692 num_sectors = sum->len / sdev->sectorsize;
a2de733c
AJ		 1693 for (i = 0; i < num_sectors; ++i) {
1694 if (sum->sums[i].bytenr == logical) {
1695 memcpy(csum, &sum->sums[i].sum, sdev->csum_size);
1696 ret = 1;
1697 break;
1698 }
1699 }
1700 if (ret && i == num_sectors - 1) {
1701 list_del(&sum->list);
1702 kfree(sum);
1703 }
1704 return ret;
1705}
1706
1707/* scrub extent tries to collect up to 64 kB for each bio */
1708static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len,
e12fa9cd 1709 u64 physical, u64 flags, u64 gen, int mirror_num)
a2de733c
AJ		 1710{
1711 int ret;
1712 u8 csum[BTRFS_CSUM_SIZE];
b5d67f64
SB		 1713 u32 blocksize;
1714
1715 if (flags & BTRFS_EXTENT_FLAG_DATA) {
1716 blocksize = sdev->sectorsize;
1717 spin_lock(&sdev->stat_lock);
1718 sdev->stat.data_extents_scrubbed++;
1719 sdev->stat.data_bytes_scrubbed += len;
1720 spin_unlock(&sdev->stat_lock);
1721 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
1722 BUG_ON(sdev->nodesize != sdev->leafsize);
1723 blocksize = sdev->nodesize;
1724 spin_lock(&sdev->stat_lock);
1725 sdev->stat.tree_extents_scrubbed++;
1726 sdev->stat.tree_bytes_scrubbed += len;
1727 spin_unlock(&sdev->stat_lock);
1728 } else {
1729 blocksize = sdev->sectorsize;
1730 BUG_ON(1);
1731 }
a2de733c
AJ		 1732
1733 while (len) {
b5d67f64 1734 u64 l = min_t(u64, len, blocksize);
a2de733c
AJ		 1735 int have_csum = 0;
1736
1737 if (flags & BTRFS_EXTENT_FLAG_DATA) {
1738 /* push csums to sbio */
1739 have_csum = scrub_find_csum(sdev, logical, l, csum);
1740 if (have_csum == 0)
1741 ++sdev->stat.no_csum;
1742 }
b5d67f64
SB		 1743 ret = scrub_pages(sdev, logical, l, physical, flags, gen,
1744 mirror_num, have_csum ? csum : NULL, 0);
a2de733c
AJ		 1745 if (ret)
1746 return ret;
1747 len -= l;
1748 logical += l;
1749 physical += l;
1750 }
1751 return 0;
1752}
1753
1754static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev,
1755 struct map_lookup *map, int num, u64 base, u64 length)
1756{
1757 struct btrfs_path *path;
1758 struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info;
1759 struct btrfs_root *root = fs_info->extent_root;
1760 struct btrfs_root *csum_root = fs_info->csum_root;
1761 struct btrfs_extent_item *extent;
e7786c3a 1762 struct blk_plug plug;
a2de733c
AJ		 1763 u64 flags;
1764 int ret;
1765 int slot;
1766 int i;
1767 u64 nstripes;
a2de733c
AJ		 1768 struct extent_buffer *l;
1769 struct btrfs_key key;
1770 u64 physical;
1771 u64 logical;
1772 u64 generation;
e12fa9cd 1773 int mirror_num;
7a26285e
AJ		 1774 struct reada_control *reada1;
1775 struct reada_control *reada2;
1776 struct btrfs_key key_start;
1777 struct btrfs_key key_end;
a2de733c
AJ		 1778
1779 u64 increment = map->stripe_len;
1780 u64 offset;
1781
1782 nstripes = length;
1783 offset = 0;
1784 do_div(nstripes, map->stripe_len);
1785 if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
1786 offset = map->stripe_len * num;
1787 increment = map->stripe_len * map->num_stripes;
193ea74b 1788 mirror_num = 1;
a2de733c
AJ		 1789 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) {
1790 int factor = map->num_stripes / map->sub_stripes;
1791 offset = map->stripe_len * (num / map->sub_stripes);
1792 increment = map->stripe_len * factor;
193ea74b 1793 mirror_num = num % map->sub_stripes + 1;
a2de733c
AJ		 1794 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) {
1795 increment = map->stripe_len;
193ea74b 1796 mirror_num = num % map->num_stripes + 1;
a2de733c
AJ		 1797 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) {
1798 increment = map->stripe_len;
193ea74b 1799 mirror_num = num % map->num_stripes + 1;
a2de733c
AJ		 1800 } else {
1801 increment = map->stripe_len;
193ea74b 1802 mirror_num = 1;
a2de733c
AJ		 1803 }
1804
1805 path = btrfs_alloc_path();
1806 if (!path)
1807 return -ENOMEM;
1808
b5d67f64
SB		 1809 /*
1810 * work on commit root. The related disk blocks are static as
1811 * long as COW is applied. This means, it is save to rewrite
1812 * them to repair disk errors without any race conditions
1813 */
a2de733c
AJ		 1814 path->search_commit_root = 1;
1815 path->skip_locking = 1;
1816
1817 /*
7a26285e
AJ		 1818 * trigger the readahead for extent tree csum tree and wait for
1819 * completion. During readahead, the scrub is officially paused
1820 * to not hold off transaction commits
a2de733c
AJ		 1821 */
1822 logical = base + offset;
a2de733c 1823
7a26285e
AJ		 1824 wait_event(sdev->list_wait,
1825 atomic_read(&sdev->in_flight) == 0);
1826 atomic_inc(&fs_info->scrubs_paused);
1827 wake_up(&fs_info->scrub_pause_wait);
1828
1829 /* FIXME it might be better to start readahead at commit root */
1830 key_start.objectid = logical;
1831 key_start.type = BTRFS_EXTENT_ITEM_KEY;
1832 key_start.offset = (u64)0;
1833 key_end.objectid = base + offset + nstripes * increment;
1834 key_end.type = BTRFS_EXTENT_ITEM_KEY;
1835 key_end.offset = (u64)0;
1836 reada1 = btrfs_reada_add(root, &key_start, &key_end);
1837
1838 key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1839 key_start.type = BTRFS_EXTENT_CSUM_KEY;
1840 key_start.offset = logical;
1841 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
1842 key_end.type = BTRFS_EXTENT_CSUM_KEY;
1843 key_end.offset = base + offset + nstripes * increment;
1844 reada2 = btrfs_reada_add(csum_root, &key_start, &key_end);
1845
1846 if (!IS_ERR(reada1))
1847 btrfs_reada_wait(reada1);
1848 if (!IS_ERR(reada2))
1849 btrfs_reada_wait(reada2);
1850
1851 mutex_lock(&fs_info->scrub_lock);
1852 while (atomic_read(&fs_info->scrub_pause_req)) {
1853 mutex_unlock(&fs_info->scrub_lock);
1854 wait_event(fs_info->scrub_pause_wait,
1855 atomic_read(&fs_info->scrub_pause_req) == 0);
1856 mutex_lock(&fs_info->scrub_lock);
a2de733c 1857 }
7a26285e
AJ		 1858 atomic_dec(&fs_info->scrubs_paused);
1859 mutex_unlock(&fs_info->scrub_lock);
1860 wake_up(&fs_info->scrub_pause_wait);
a2de733c
AJ		 1861
1862 /*
1863 * collect all data csums for the stripe to avoid seeking during
1864 * the scrub. This might currently (crc32) end up to be about 1MB
1865 */
e7786c3a 1866 blk_start_plug(&plug);
a2de733c 1867
a2de733c
AJ		 1868 /*
1869 * now find all extents for each stripe and scrub them
1870 */
7a26285e
AJ		 1871 logical = base + offset;
1872 physical = map->stripes[num].physical;
a2de733c 1873 ret = 0;
7a26285e 1874 for (i = 0; i < nstripes; ++i) {
a2de733c
AJ		 1875 /*
1876 * canceled?
1877 */
1878 if (atomic_read(&fs_info->scrub_cancel_req) ||
1879 atomic_read(&sdev->cancel_req)) {
1880 ret = -ECANCELED;
1881 goto out;
1882 }
1883 /*
1884 * check to see if we have to pause
1885 */
1886 if (atomic_read(&fs_info->scrub_pause_req)) {
1887 /* push queued extents */
1888 scrub_submit(sdev);
1889 wait_event(sdev->list_wait,
1890 atomic_read(&sdev->in_flight) == 0);
1891 atomic_inc(&fs_info->scrubs_paused);
1892 wake_up(&fs_info->scrub_pause_wait);
1893 mutex_lock(&fs_info->scrub_lock);
1894 while (atomic_read(&fs_info->scrub_pause_req)) {
1895 mutex_unlock(&fs_info->scrub_lock);
1896 wait_event(fs_info->scrub_pause_wait,
1897 atomic_read(&fs_info->scrub_pause_req) == 0);
1898 mutex_lock(&fs_info->scrub_lock);
1899 }
1900 atomic_dec(&fs_info->scrubs_paused);
1901 mutex_unlock(&fs_info->scrub_lock);
1902 wake_up(&fs_info->scrub_pause_wait);
a2de733c
AJ		 1903 }
1904
7a26285e
AJ		 1905 ret = btrfs_lookup_csums_range(csum_root, logical,
1906 logical + map->stripe_len - 1,
1907 &sdev->csum_list, 1);
1908 if (ret)
1909 goto out;
1910
a2de733c
AJ		 1911 key.objectid = logical;
1912 key.type = BTRFS_EXTENT_ITEM_KEY;
1913 key.offset = (u64)0;
1914
1915 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1916 if (ret < 0)
1917 goto out;
8c51032f 1918 if (ret > 0) {
a2de733c
AJ		 1919 ret = btrfs_previous_item(root, path, 0,
1920 BTRFS_EXTENT_ITEM_KEY);
1921 if (ret < 0)
1922 goto out;
8c51032f
AJ		 1923 if (ret > 0) {
1924 /* there's no smaller item, so stick with the
1925 * larger one */
1926 btrfs_release_path(path);
1927 ret = btrfs_search_slot(NULL, root, &key,
1928 path, 0, 0);
1929 if (ret < 0)
1930 goto out;
1931 }
a2de733c
AJ		 1932 }
1933
1934 while (1) {
1935 l = path->nodes[0];
1936 slot = path->slots[0];
1937 if (slot >= btrfs_header_nritems(l)) {
1938 ret = btrfs_next_leaf(root, path);
1939 if (ret == 0)
1940 continue;
1941 if (ret < 0)
1942 goto out;
1943
1944 break;
1945 }
1946 btrfs_item_key_to_cpu(l, &key, slot);
1947
1948 if (key.objectid + key.offset <= logical)
1949 goto next;
1950
1951 if (key.objectid >= logical + map->stripe_len)
1952 break;
1953
1954 if (btrfs_key_type(&key) != BTRFS_EXTENT_ITEM_KEY)
1955 goto next;
1956
1957 extent = btrfs_item_ptr(l, slot,
1958 struct btrfs_extent_item);
1959 flags = btrfs_extent_flags(l, extent);
1960 generation = btrfs_extent_generation(l, extent);
1961
1962 if (key.objectid < logical &&
1963 (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) {
1964 printk(KERN_ERR
1965 "btrfs scrub: tree block %llu spanning "
1966 "stripes, ignored. logical=%llu\n",
1967 (unsigned long long)key.objectid,
1968 (unsigned long long)logical);
1969 goto next;
1970 }
1971
1972 /*
1973 * trim extent to this stripe
1974 */
1975 if (key.objectid < logical) {
1976 key.offset -= logical - key.objectid;
1977 key.objectid = logical;
1978 }
1979 if (key.objectid + key.offset >
1980 logical + map->stripe_len) {
1981 key.offset = logical + map->stripe_len -
1982 key.objectid;
1983 }
1984
1985 ret = scrub_extent(sdev, key.objectid, key.offset,
1986 key.objectid - logical + physical,
1987 flags, generation, mirror_num);
1988 if (ret)
1989 goto out;
1990
1991next:
1992 path->slots[0]++;
1993 }
71267333 1994 btrfs_release_path(path);
a2de733c
AJ		 1995 logical += increment;
1996 physical += map->stripe_len;
1997 spin_lock(&sdev->stat_lock);
1998 sdev->stat.last_physical = physical;
1999 spin_unlock(&sdev->stat_lock);
2000 }
2001 /* push queued extents */
2002 scrub_submit(sdev);
2003
2004out:
e7786c3a 2005 blk_finish_plug(&plug);
a2de733c
AJ		 2006 btrfs_free_path(path);
2007 return ret < 0 ? ret : 0;
2008}
2009
2010static noinline_for_stack int scrub_chunk(struct scrub_dev *sdev,
859acaf1
AJ		 2011 u64 chunk_tree, u64 chunk_objectid, u64 chunk_offset, u64 length,
2012 u64 dev_offset)
a2de733c
AJ		 2013{
2014 struct btrfs_mapping_tree *map_tree =
2015 &sdev->dev->dev_root->fs_info->mapping_tree;
2016 struct map_lookup *map;
2017 struct extent_map *em;
2018 int i;
2019 int ret = -EINVAL;
2020
2021 read_lock(&map_tree->map_tree.lock);
2022 em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1);
2023 read_unlock(&map_tree->map_tree.lock);
2024
2025 if (!em)
2026 return -EINVAL;
2027
2028 map = (struct map_lookup *)em->bdev;
2029 if (em->start != chunk_offset)
2030 goto out;
2031
2032 if (em->len < length)
2033 goto out;
2034
2035 for (i = 0; i < map->num_stripes; ++i) {
859acaf1
AJ		 2036 if (map->stripes[i].dev == sdev->dev &&
2037 map->stripes[i].physical == dev_offset) {
a2de733c
AJ		 2038 ret = scrub_stripe(sdev, map, i, chunk_offset, length);
2039 if (ret)
2040 goto out;
2041 }
2042 }
2043out:
2044 free_extent_map(em);
2045
2046 return ret;
2047}
2048
2049static noinline_for_stack
2050int scrub_enumerate_chunks(struct scrub_dev *sdev, u64 start, u64 end)
2051{
2052 struct btrfs_dev_extent *dev_extent = NULL;
2053 struct btrfs_path *path;
2054 struct btrfs_root *root = sdev->dev->dev_root;
2055 struct btrfs_fs_info *fs_info = root->fs_info;
2056 u64 length;
2057 u64 chunk_tree;
2058 u64 chunk_objectid;
2059 u64 chunk_offset;
2060 int ret;
2061 int slot;
2062 struct extent_buffer *l;
2063 struct btrfs_key key;
2064 struct btrfs_key found_key;
2065 struct btrfs_block_group_cache *cache;
2066
2067 path = btrfs_alloc_path();
2068 if (!path)
2069 return -ENOMEM;
2070
2071 path->reada = 2;
2072 path->search_commit_root = 1;
2073 path->skip_locking = 1;
2074
2075 key.objectid = sdev->dev->devid;
2076 key.offset = 0ull;
2077 key.type = BTRFS_DEV_EXTENT_KEY;
2078
2079
2080 while (1) {
2081 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2082 if (ret < 0)
8c51032f
AJ		 2083 break;
2084 if (ret > 0) {
2085 if (path->slots[0] >=
2086 btrfs_header_nritems(path->nodes[0])) {
2087 ret = btrfs_next_leaf(root, path);
2088 if (ret)
2089 break;
2090 }
2091 }
a2de733c
AJ		 2092
2093 l = path->nodes[0];
2094 slot = path->slots[0];
2095
2096 btrfs_item_key_to_cpu(l, &found_key, slot);
2097
2098 if (found_key.objectid != sdev->dev->devid)
2099 break;
2100
8c51032f 2101 if (btrfs_key_type(&found_key) != BTRFS_DEV_EXTENT_KEY)
a2de733c
AJ		 2102 break;
2103
2104 if (found_key.offset >= end)
2105 break;
2106
2107 if (found_key.offset < key.offset)
2108 break;
2109
2110 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent);
2111 length = btrfs_dev_extent_length(l, dev_extent);
2112
2113 if (found_key.offset + length <= start) {
2114 key.offset = found_key.offset + length;
71267333 2115 btrfs_release_path(path);
a2de733c
AJ		 2116 continue;
2117 }
2118
2119 chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent);
2120 chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent);
2121 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent);
2122
2123 /*
2124 * get a reference on the corresponding block group to prevent
2125 * the chunk from going away while we scrub it
2126 */
2127 cache = btrfs_lookup_block_group(fs_info, chunk_offset);
2128 if (!cache) {
2129 ret = -ENOENT;
8c51032f 2130 break;
a2de733c
AJ		 2131 }
2132 ret = scrub_chunk(sdev, chunk_tree, chunk_objectid,
859acaf1 2133 chunk_offset, length, found_key.offset);
a2de733c
AJ		 2134 btrfs_put_block_group(cache);
2135 if (ret)
2136 break;
2137
2138 key.offset = found_key.offset + length;
71267333 2139 btrfs_release_path(path);
a2de733c
AJ		 2140 }
2141
a2de733c 2142 btrfs_free_path(path);
8c51032f
AJ		 2143
2144 /*
2145 * ret can still be 1 from search_slot or next_leaf,
2146 * that's not an error
2147 */
2148 return ret < 0 ? ret : 0;
a2de733c
AJ		 2149}
2150
2151static noinline_for_stack int scrub_supers(struct scrub_dev *sdev)
2152{
2153 int i;
2154 u64 bytenr;
2155 u64 gen;
2156 int ret;
2157 struct btrfs_device *device = sdev->dev;
2158 struct btrfs_root *root = device->dev_root;
2159
79787eaa
JM		 2160 if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR)
2161 return -EIO;
2162
a2de733c
AJ		 2163 gen = root->fs_info->last_trans_committed;
2164
2165 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
2166 bytenr = btrfs_sb_offset(i);
1623edeb 2167 if (bytenr + BTRFS_SUPER_INFO_SIZE > device->total_bytes)
a2de733c
AJ		 2168 break;
2169
b5d67f64
SB		 2170 ret = scrub_pages(sdev, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr,
2171 BTRFS_EXTENT_FLAG_SUPER, gen, i, NULL, 1);
a2de733c
AJ		 2172 if (ret)
2173 return ret;
2174 }
2175 wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0);
2176
2177 return 0;
2178}
2179
2180/*
2181 * get a reference count on fs_info->scrub_workers. start worker if necessary
2182 */
2183static noinline_for_stack int scrub_workers_get(struct btrfs_root *root)
2184{
2185 struct btrfs_fs_info *fs_info = root->fs_info;
0dc3b84a 2186 int ret = 0;
a2de733c
AJ		 2187
2188 mutex_lock(&fs_info->scrub_lock);
632dd772
AJ		 2189 if (fs_info->scrub_workers_refcnt == 0) {
2190 btrfs_init_workers(&fs_info->scrub_workers, "scrub",
2191 fs_info->thread_pool_size, &fs_info->generic_worker);
2192 fs_info->scrub_workers.idle_thresh = 4;
0dc3b84a
JB		 2193 ret = btrfs_start_workers(&fs_info->scrub_workers);
2194 if (ret)
2195 goto out;
632dd772 2196 }
a2de733c 2197 ++fs_info->scrub_workers_refcnt;
0dc3b84a 2198out:
a2de733c
AJ		 2199 mutex_unlock(&fs_info->scrub_lock);
2200
0dc3b84a 2201 return ret;
a2de733c
AJ		 2202}
2203
2204static noinline_for_stack void scrub_workers_put(struct btrfs_root *root)
2205{
2206 struct btrfs_fs_info *fs_info = root->fs_info;
2207
2208 mutex_lock(&fs_info->scrub_lock);
2209 if (--fs_info->scrub_workers_refcnt == 0)
2210 btrfs_stop_workers(&fs_info->scrub_workers);
2211 WARN_ON(fs_info->scrub_workers_refcnt < 0);
2212 mutex_unlock(&fs_info->scrub_lock);
2213}
2214
2215
2216int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end,
8628764e 2217 struct btrfs_scrub_progress *progress, int readonly)
a2de733c
AJ		 2218{
2219 struct scrub_dev *sdev;
2220 struct btrfs_fs_info *fs_info = root->fs_info;
2221 int ret;
2222 struct btrfs_device *dev;
2223
7841cb28 2224 if (btrfs_fs_closing(root->fs_info))
a2de733c
AJ		 2225 return -EINVAL;
2226
2227 /*
2228 * check some assumptions
2229 */
b5d67f64
SB		 2230 if (root->nodesize != root->leafsize) {
2231 printk(KERN_ERR
2232 "btrfs_scrub: size assumption nodesize == leafsize (%d == %d) fails\n",
2233 root->nodesize, root->leafsize);
2234 return -EINVAL;
2235 }
2236
2237 if (root->nodesize > BTRFS_STRIPE_LEN) {
2238 /*
2239 * in this case scrub is unable to calculate the checksum
2240 * the way scrub is implemented. Do not handle this
2241 * situation at all because it won't ever happen.
2242 */
2243 printk(KERN_ERR
2244 "btrfs_scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails\n",
2245 root->nodesize, BTRFS_STRIPE_LEN);
2246 return -EINVAL;
2247 }
2248
2249 if (root->sectorsize != PAGE_SIZE) {
2250 /* not supported for data w/o checksums */
2251 printk(KERN_ERR
2252 "btrfs_scrub: size assumption sectorsize != PAGE_SIZE (%d != %lld) fails\n",
2253 root->sectorsize, (unsigned long long)PAGE_SIZE);
a2de733c
AJ		 2254 return -EINVAL;
2255 }
2256
2257 ret = scrub_workers_get(root);
2258 if (ret)
2259 return ret;
2260
2261 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2262 dev = btrfs_find_device(root, devid, NULL, NULL);
2263 if (!dev || dev->missing) {
2264 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2265 scrub_workers_put(root);
2266 return -ENODEV;
2267 }
2268 mutex_lock(&fs_info->scrub_lock);
2269
2270 if (!dev->in_fs_metadata) {
2271 mutex_unlock(&fs_info->scrub_lock);
2272 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2273 scrub_workers_put(root);
2274 return -ENODEV;
2275 }
2276
2277 if (dev->scrub_device) {
2278 mutex_unlock(&fs_info->scrub_lock);
2279 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2280 scrub_workers_put(root);
2281 return -EINPROGRESS;
2282 }
2283 sdev = scrub_setup_dev(dev);
2284 if (IS_ERR(sdev)) {
2285 mutex_unlock(&fs_info->scrub_lock);
2286 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2287 scrub_workers_put(root);
2288 return PTR_ERR(sdev);
2289 }
8628764e 2290 sdev->readonly = readonly;
a2de733c
AJ		 2291 dev->scrub_device = sdev;
2292
2293 atomic_inc(&fs_info->scrubs_running);
2294 mutex_unlock(&fs_info->scrub_lock);
2295 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2296
2297 down_read(&fs_info->scrub_super_lock);
2298 ret = scrub_supers(sdev);
2299 up_read(&fs_info->scrub_super_lock);
2300
2301 if (!ret)
2302 ret = scrub_enumerate_chunks(sdev, start, end);
2303
2304 wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0);
a2de733c
AJ		 2305 atomic_dec(&fs_info->scrubs_running);
2306 wake_up(&fs_info->scrub_pause_wait);
2307
0ef8e451
JS		 2308 wait_event(sdev->list_wait, atomic_read(&sdev->fixup_cnt) == 0);
2309
a2de733c
AJ		 2310 if (progress)
2311 memcpy(progress, &sdev->stat, sizeof(*progress));
2312
2313 mutex_lock(&fs_info->scrub_lock);
2314 dev->scrub_device = NULL;
2315 mutex_unlock(&fs_info->scrub_lock);
2316
2317 scrub_free_dev(sdev);
2318 scrub_workers_put(root);
2319
2320 return ret;
2321}
2322
143bede5 2323void btrfs_scrub_pause(struct btrfs_root *root)
a2de733c
AJ		 2324{
2325 struct btrfs_fs_info *fs_info = root->fs_info;
2326
2327 mutex_lock(&fs_info->scrub_lock);
2328 atomic_inc(&fs_info->scrub_pause_req);
2329 while (atomic_read(&fs_info->scrubs_paused) !=
2330 atomic_read(&fs_info->scrubs_running)) {
2331 mutex_unlock(&fs_info->scrub_lock);
2332 wait_event(fs_info->scrub_pause_wait,
2333 atomic_read(&fs_info->scrubs_paused) ==
2334 atomic_read(&fs_info->scrubs_running));
2335 mutex_lock(&fs_info->scrub_lock);
2336 }
2337 mutex_unlock(&fs_info->scrub_lock);
a2de733c
AJ		 2338}
2339
143bede5 2340void btrfs_scrub_continue(struct btrfs_root *root)
a2de733c
AJ		 2341{
2342 struct btrfs_fs_info *fs_info = root->fs_info;
2343
2344 atomic_dec(&fs_info->scrub_pause_req);
2345 wake_up(&fs_info->scrub_pause_wait);
a2de733c
AJ		 2346}
2347
143bede5 2348void btrfs_scrub_pause_super(struct btrfs_root *root)
a2de733c
AJ		 2349{
2350 down_write(&root->fs_info->scrub_super_lock);
a2de733c
AJ		 2351}
2352
143bede5 2353void btrfs_scrub_continue_super(struct btrfs_root *root)
a2de733c
AJ		 2354{
2355 up_write(&root->fs_info->scrub_super_lock);
a2de733c
AJ		 2356}
2357
49b25e05 2358int __btrfs_scrub_cancel(struct btrfs_fs_info *fs_info)
a2de733c 2359{
a2de733c
AJ		 2360
2361 mutex_lock(&fs_info->scrub_lock);
2362 if (!atomic_read(&fs_info->scrubs_running)) {
2363 mutex_unlock(&fs_info->scrub_lock);
2364 return -ENOTCONN;
2365 }
2366
2367 atomic_inc(&fs_info->scrub_cancel_req);
2368 while (atomic_read(&fs_info->scrubs_running)) {
2369 mutex_unlock(&fs_info->scrub_lock);
2370 wait_event(fs_info->scrub_pause_wait,
2371 atomic_read(&fs_info->scrubs_running) == 0);
2372 mutex_lock(&fs_info->scrub_lock);
2373 }
2374 atomic_dec(&fs_info->scrub_cancel_req);
2375 mutex_unlock(&fs_info->scrub_lock);
2376
2377 return 0;
2378}
2379
49b25e05
JM		 2380int btrfs_scrub_cancel(struct btrfs_root *root)
2381{
2382 return __btrfs_scrub_cancel(root->fs_info);
2383}
2384
a2de733c
AJ		 2385int btrfs_scrub_cancel_dev(struct btrfs_root *root, struct btrfs_device *dev)
2386{
2387 struct btrfs_fs_info *fs_info = root->fs_info;
2388 struct scrub_dev *sdev;
2389
2390 mutex_lock(&fs_info->scrub_lock);
2391 sdev = dev->scrub_device;
2392 if (!sdev) {
2393 mutex_unlock(&fs_info->scrub_lock);
2394 return -ENOTCONN;
2395 }
2396 atomic_inc(&sdev->cancel_req);
2397 while (dev->scrub_device) {
2398 mutex_unlock(&fs_info->scrub_lock);
2399 wait_event(fs_info->scrub_pause_wait,
2400 dev->scrub_device == NULL);
2401 mutex_lock(&fs_info->scrub_lock);
2402 }
2403 mutex_unlock(&fs_info->scrub_lock);
2404
2405 return 0;
2406}
1623edeb 2407
a2de733c
AJ		 2408int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid)
2409{
2410 struct btrfs_fs_info *fs_info = root->fs_info;
2411 struct btrfs_device *dev;
2412 int ret;
2413
2414 /*
2415 * we have to hold the device_list_mutex here so the device
2416 * does not go away in cancel_dev. FIXME: find a better solution
2417 */
2418 mutex_lock(&fs_info->fs_devices->device_list_mutex);
2419 dev = btrfs_find_device(root, devid, NULL, NULL);
2420 if (!dev) {
2421 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2422 return -ENODEV;
2423 }
2424 ret = btrfs_scrub_cancel_dev(root, dev);
2425 mutex_unlock(&fs_info->fs_devices->device_list_mutex);
2426
2427 return ret;
2428}
2429
2430int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
2431 struct btrfs_scrub_progress *progress)
2432{
2433 struct btrfs_device *dev;
2434 struct scrub_dev *sdev = NULL;
2435
2436 mutex_lock(&root->fs_info->fs_devices->device_list_mutex);
2437 dev = btrfs_find_device(root, devid, NULL, NULL);
2438 if (dev)
2439 sdev = dev->scrub_device;
2440 if (sdev)
2441 memcpy(progress, &sdev->stat, sizeof(*progress));
2442 mutex_unlock(&root->fs_info->fs_devices->device_list_mutex);
2443
2444 return dev ? (sdev ? 0 : -ENOTCONN) : -ENODEV;
2445}
Linux kernel - Deliverables
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