1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2011, 2012 STRATO. All rights reserved. 4 */ 5 6 #include <linux/blkdev.h> 7 #include <linux/ratelimit.h> 8 #include <linux/sched/mm.h> 9 #include <crypto/hash.h> 10 #include "ctree.h" 11 #include "volumes.h" 12 #include "disk-io.h" 13 #include "ordered-data.h" 14 #include "transaction.h" 15 #include "backref.h" 16 #include "extent_io.h" 17 #include "dev-replace.h" 18 #include "check-integrity.h" 19 #include "rcu-string.h" 20 #include "raid56.h" 21 #include "block-group.h" 22 23 /* 24 * This is only the first step towards a full-features scrub. It reads all 25 * extent and super block and verifies the checksums. In case a bad checksum 26 * is found or the extent cannot be read, good data will be written back if 27 * any can be found. 28 * 29 * Future enhancements: 30 * - In case an unrepairable extent is encountered, track which files are 31 * affected and report them 32 * - track and record media errors, throw out bad devices 33 * - add a mode to also read unallocated space 34 */ 35 36 struct scrub_block; 37 struct scrub_ctx; 38 39 /* 40 * the following three values only influence the performance. 41 * The last one configures the number of parallel and outstanding I/O 42 * operations. The first two values configure an upper limit for the number 43 * of (dynamically allocated) pages that are added to a bio. 44 */ 45 #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */ 46 #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */ 47 #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */ 48 49 /* 50 * the following value times PAGE_SIZE needs to be large enough to match the 51 * largest node/leaf/sector size that shall be supported. 52 * Values larger than BTRFS_STRIPE_LEN are not supported. 53 */ 54 #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */ 55 56 struct scrub_recover { 57 refcount_t refs; 58 struct btrfs_bio *bbio; 59 u64 map_length; 60 }; 61 62 struct scrub_page { 63 struct scrub_block *sblock; 64 struct page *page; 65 struct btrfs_device *dev; 66 struct list_head list; 67 u64 flags; /* extent flags */ 68 u64 generation; 69 u64 logical; 70 u64 physical; 71 u64 physical_for_dev_replace; 72 atomic_t refs; 73 struct { 74 unsigned int mirror_num:8; 75 unsigned int have_csum:1; 76 unsigned int io_error:1; 77 }; 78 u8 csum[BTRFS_CSUM_SIZE]; 79 80 struct scrub_recover *recover; 81 }; 82 83 struct scrub_bio { 84 int index; 85 struct scrub_ctx *sctx; 86 struct btrfs_device *dev; 87 struct bio *bio; 88 blk_status_t status; 89 u64 logical; 90 u64 physical; 91 #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO 92 struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO]; 93 #else 94 struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO]; 95 #endif 96 int page_count; 97 int next_free; 98 struct btrfs_work work; 99 }; 100 101 struct scrub_block { 102 struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK]; 103 int page_count; 104 atomic_t outstanding_pages; 105 refcount_t refs; /* free mem on transition to zero */ 106 struct scrub_ctx *sctx; 107 struct scrub_parity *sparity; 108 struct { 109 unsigned int header_error:1; 110 unsigned int checksum_error:1; 111 unsigned int no_io_error_seen:1; 112 unsigned int generation_error:1; /* also sets header_error */ 113 114 /* The following is for the data used to check parity */ 115 /* It is for the data with checksum */ 116 unsigned int data_corrected:1; 117 }; 118 struct btrfs_work work; 119 }; 120 121 /* Used for the chunks with parity stripe such RAID5/6 */ 122 struct scrub_parity { 123 struct scrub_ctx *sctx; 124 125 struct btrfs_device *scrub_dev; 126 127 u64 logic_start; 128 129 u64 logic_end; 130 131 int nsectors; 132 133 u64 stripe_len; 134 135 refcount_t refs; 136 137 struct list_head spages; 138 139 /* Work of parity check and repair */ 140 struct btrfs_work work; 141 142 /* Mark the parity blocks which have data */ 143 unsigned long *dbitmap; 144 145 /* 146 * Mark the parity blocks which have data, but errors happen when 147 * read data or check data 148 */ 149 unsigned long *ebitmap; 150 151 unsigned long bitmap[0]; 152 }; 153 154 struct scrub_ctx { 155 struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX]; 156 struct btrfs_fs_info *fs_info; 157 int first_free; 158 int curr; 159 atomic_t bios_in_flight; 160 atomic_t workers_pending; 161 spinlock_t list_lock; 162 wait_queue_head_t list_wait; 163 u16 csum_size; 164 struct list_head csum_list; 165 atomic_t cancel_req; 166 int readonly; 167 int pages_per_rd_bio; 168 169 int is_dev_replace; 170 171 struct scrub_bio *wr_curr_bio; 172 struct mutex wr_lock; 173 int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */ 174 struct btrfs_device *wr_tgtdev; 175 bool flush_all_writes; 176 177 /* 178 * statistics 179 */ 180 struct btrfs_scrub_progress stat; 181 spinlock_t stat_lock; 182 183 /* 184 * Use a ref counter to avoid use-after-free issues. Scrub workers 185 * decrement bios_in_flight and workers_pending and then do a wakeup 186 * on the list_wait wait queue. We must ensure the main scrub task 187 * doesn't free the scrub context before or while the workers are 188 * doing the wakeup() call. 189 */ 190 refcount_t refs; 191 }; 192 193 struct scrub_warning { 194 struct btrfs_path *path; 195 u64 extent_item_size; 196 const char *errstr; 197 u64 physical; 198 u64 logical; 199 struct btrfs_device *dev; 200 }; 201 202 struct full_stripe_lock { 203 struct rb_node node; 204 u64 logical; 205 u64 refs; 206 struct mutex mutex; 207 }; 208 209 static void scrub_pending_bio_inc(struct scrub_ctx *sctx); 210 static void scrub_pending_bio_dec(struct scrub_ctx *sctx); 211 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check); 212 static int scrub_setup_recheck_block(struct scrub_block *original_sblock, 213 struct scrub_block *sblocks_for_recheck); 214 static void scrub_recheck_block(struct btrfs_fs_info *fs_info, 215 struct scrub_block *sblock, 216 int retry_failed_mirror); 217 static void scrub_recheck_block_checksum(struct scrub_block *sblock); 218 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, 219 struct scrub_block *sblock_good); 220 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad, 221 struct scrub_block *sblock_good, 222 int page_num, int force_write); 223 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock); 224 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock, 225 int page_num); 226 static int scrub_checksum_data(struct scrub_block *sblock); 227 static int scrub_checksum_tree_block(struct scrub_block *sblock); 228 static int scrub_checksum_super(struct scrub_block *sblock); 229 static void scrub_block_get(struct scrub_block *sblock); 230 static void scrub_block_put(struct scrub_block *sblock); 231 static void scrub_page_get(struct scrub_page *spage); 232 static void scrub_page_put(struct scrub_page *spage); 233 static void scrub_parity_get(struct scrub_parity *sparity); 234 static void scrub_parity_put(struct scrub_parity *sparity); 235 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx, 236 struct scrub_page *spage); 237 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len, 238 u64 physical, struct btrfs_device *dev, u64 flags, 239 u64 gen, int mirror_num, u8 *csum, int force, 240 u64 physical_for_dev_replace); 241 static void scrub_bio_end_io(struct bio *bio); 242 static void scrub_bio_end_io_worker(struct btrfs_work *work); 243 static void scrub_block_complete(struct scrub_block *sblock); 244 static void scrub_remap_extent(struct btrfs_fs_info *fs_info, 245 u64 extent_logical, u64 extent_len, 246 u64 *extent_physical, 247 struct btrfs_device **extent_dev, 248 int *extent_mirror_num); 249 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx, 250 struct scrub_page *spage); 251 static void scrub_wr_submit(struct scrub_ctx *sctx); 252 static void scrub_wr_bio_end_io(struct bio *bio); 253 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work); 254 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info); 255 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info); 256 static void scrub_put_ctx(struct scrub_ctx *sctx); 257 258 static inline int scrub_is_page_on_raid56(struct scrub_page *page) 259 { 260 return page->recover && 261 (page->recover->bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK); 262 } 263 264 static void scrub_pending_bio_inc(struct scrub_ctx *sctx) 265 { 266 refcount_inc(&sctx->refs); 267 atomic_inc(&sctx->bios_in_flight); 268 } 269 270 static void scrub_pending_bio_dec(struct scrub_ctx *sctx) 271 { 272 atomic_dec(&sctx->bios_in_flight); 273 wake_up(&sctx->list_wait); 274 scrub_put_ctx(sctx); 275 } 276 277 static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info) 278 { 279 while (atomic_read(&fs_info->scrub_pause_req)) { 280 mutex_unlock(&fs_info->scrub_lock); 281 wait_event(fs_info->scrub_pause_wait, 282 atomic_read(&fs_info->scrub_pause_req) == 0); 283 mutex_lock(&fs_info->scrub_lock); 284 } 285 } 286 287 static void scrub_pause_on(struct btrfs_fs_info *fs_info) 288 { 289 atomic_inc(&fs_info->scrubs_paused); 290 wake_up(&fs_info->scrub_pause_wait); 291 } 292 293 static void scrub_pause_off(struct btrfs_fs_info *fs_info) 294 { 295 mutex_lock(&fs_info->scrub_lock); 296 __scrub_blocked_if_needed(fs_info); 297 atomic_dec(&fs_info->scrubs_paused); 298 mutex_unlock(&fs_info->scrub_lock); 299 300 wake_up(&fs_info->scrub_pause_wait); 301 } 302 303 static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info) 304 { 305 scrub_pause_on(fs_info); 306 scrub_pause_off(fs_info); 307 } 308 309 /* 310 * Insert new full stripe lock into full stripe locks tree 311 * 312 * Return pointer to existing or newly inserted full_stripe_lock structure if 313 * everything works well. 314 * Return ERR_PTR(-ENOMEM) if we failed to allocate memory 315 * 316 * NOTE: caller must hold full_stripe_locks_root->lock before calling this 317 * function 318 */ 319 static struct full_stripe_lock *insert_full_stripe_lock( 320 struct btrfs_full_stripe_locks_tree *locks_root, 321 u64 fstripe_logical) 322 { 323 struct rb_node **p; 324 struct rb_node *parent = NULL; 325 struct full_stripe_lock *entry; 326 struct full_stripe_lock *ret; 327 328 lockdep_assert_held(&locks_root->lock); 329 330 p = &locks_root->root.rb_node; 331 while (*p) { 332 parent = *p; 333 entry = rb_entry(parent, struct full_stripe_lock, node); 334 if (fstripe_logical < entry->logical) { 335 p = &(*p)->rb_left; 336 } else if (fstripe_logical > entry->logical) { 337 p = &(*p)->rb_right; 338 } else { 339 entry->refs++; 340 return entry; 341 } 342 } 343 344 /* 345 * Insert new lock. 346 */ 347 ret = kmalloc(sizeof(*ret), GFP_KERNEL); 348 if (!ret) 349 return ERR_PTR(-ENOMEM); 350 ret->logical = fstripe_logical; 351 ret->refs = 1; 352 mutex_init(&ret->mutex); 353 354 rb_link_node(&ret->node, parent, p); 355 rb_insert_color(&ret->node, &locks_root->root); 356 return ret; 357 } 358 359 /* 360 * Search for a full stripe lock of a block group 361 * 362 * Return pointer to existing full stripe lock if found 363 * Return NULL if not found 364 */ 365 static struct full_stripe_lock *search_full_stripe_lock( 366 struct btrfs_full_stripe_locks_tree *locks_root, 367 u64 fstripe_logical) 368 { 369 struct rb_node *node; 370 struct full_stripe_lock *entry; 371 372 lockdep_assert_held(&locks_root->lock); 373 374 node = locks_root->root.rb_node; 375 while (node) { 376 entry = rb_entry(node, struct full_stripe_lock, node); 377 if (fstripe_logical < entry->logical) 378 node = node->rb_left; 379 else if (fstripe_logical > entry->logical) 380 node = node->rb_right; 381 else 382 return entry; 383 } 384 return NULL; 385 } 386 387 /* 388 * Helper to get full stripe logical from a normal bytenr. 389 * 390 * Caller must ensure @cache is a RAID56 block group. 391 */ 392 static u64 get_full_stripe_logical(struct btrfs_block_group *cache, u64 bytenr) 393 { 394 u64 ret; 395 396 /* 397 * Due to chunk item size limit, full stripe length should not be 398 * larger than U32_MAX. Just a sanity check here. 399 */ 400 WARN_ON_ONCE(cache->full_stripe_len >= U32_MAX); 401 402 /* 403 * round_down() can only handle power of 2, while RAID56 full 404 * stripe length can be 64KiB * n, so we need to manually round down. 405 */ 406 ret = div64_u64(bytenr - cache->start, cache->full_stripe_len) * 407 cache->full_stripe_len + cache->start; 408 return ret; 409 } 410 411 /* 412 * Lock a full stripe to avoid concurrency of recovery and read 413 * 414 * It's only used for profiles with parities (RAID5/6), for other profiles it 415 * does nothing. 416 * 417 * Return 0 if we locked full stripe covering @bytenr, with a mutex held. 418 * So caller must call unlock_full_stripe() at the same context. 419 * 420 * Return <0 if encounters error. 421 */ 422 static int lock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr, 423 bool *locked_ret) 424 { 425 struct btrfs_block_group *bg_cache; 426 struct btrfs_full_stripe_locks_tree *locks_root; 427 struct full_stripe_lock *existing; 428 u64 fstripe_start; 429 int ret = 0; 430 431 *locked_ret = false; 432 bg_cache = btrfs_lookup_block_group(fs_info, bytenr); 433 if (!bg_cache) { 434 ASSERT(0); 435 return -ENOENT; 436 } 437 438 /* Profiles not based on parity don't need full stripe lock */ 439 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK)) 440 goto out; 441 locks_root = &bg_cache->full_stripe_locks_root; 442 443 fstripe_start = get_full_stripe_logical(bg_cache, bytenr); 444 445 /* Now insert the full stripe lock */ 446 mutex_lock(&locks_root->lock); 447 existing = insert_full_stripe_lock(locks_root, fstripe_start); 448 mutex_unlock(&locks_root->lock); 449 if (IS_ERR(existing)) { 450 ret = PTR_ERR(existing); 451 goto out; 452 } 453 mutex_lock(&existing->mutex); 454 *locked_ret = true; 455 out: 456 btrfs_put_block_group(bg_cache); 457 return ret; 458 } 459 460 /* 461 * Unlock a full stripe. 462 * 463 * NOTE: Caller must ensure it's the same context calling corresponding 464 * lock_full_stripe(). 465 * 466 * Return 0 if we unlock full stripe without problem. 467 * Return <0 for error 468 */ 469 static int unlock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr, 470 bool locked) 471 { 472 struct btrfs_block_group *bg_cache; 473 struct btrfs_full_stripe_locks_tree *locks_root; 474 struct full_stripe_lock *fstripe_lock; 475 u64 fstripe_start; 476 bool freeit = false; 477 int ret = 0; 478 479 /* If we didn't acquire full stripe lock, no need to continue */ 480 if (!locked) 481 return 0; 482 483 bg_cache = btrfs_lookup_block_group(fs_info, bytenr); 484 if (!bg_cache) { 485 ASSERT(0); 486 return -ENOENT; 487 } 488 if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK)) 489 goto out; 490 491 locks_root = &bg_cache->full_stripe_locks_root; 492 fstripe_start = get_full_stripe_logical(bg_cache, bytenr); 493 494 mutex_lock(&locks_root->lock); 495 fstripe_lock = search_full_stripe_lock(locks_root, fstripe_start); 496 /* Unpaired unlock_full_stripe() detected */ 497 if (!fstripe_lock) { 498 WARN_ON(1); 499 ret = -ENOENT; 500 mutex_unlock(&locks_root->lock); 501 goto out; 502 } 503 504 if (fstripe_lock->refs == 0) { 505 WARN_ON(1); 506 btrfs_warn(fs_info, "full stripe lock at %llu refcount underflow", 507 fstripe_lock->logical); 508 } else { 509 fstripe_lock->refs--; 510 } 511 512 if (fstripe_lock->refs == 0) { 513 rb_erase(&fstripe_lock->node, &locks_root->root); 514 freeit = true; 515 } 516 mutex_unlock(&locks_root->lock); 517 518 mutex_unlock(&fstripe_lock->mutex); 519 if (freeit) 520 kfree(fstripe_lock); 521 out: 522 btrfs_put_block_group(bg_cache); 523 return ret; 524 } 525 526 static void scrub_free_csums(struct scrub_ctx *sctx) 527 { 528 while (!list_empty(&sctx->csum_list)) { 529 struct btrfs_ordered_sum *sum; 530 sum = list_first_entry(&sctx->csum_list, 531 struct btrfs_ordered_sum, list); 532 list_del(&sum->list); 533 kfree(sum); 534 } 535 } 536 537 static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx) 538 { 539 int i; 540 541 if (!sctx) 542 return; 543 544 /* this can happen when scrub is cancelled */ 545 if (sctx->curr != -1) { 546 struct scrub_bio *sbio = sctx->bios[sctx->curr]; 547 548 for (i = 0; i < sbio->page_count; i++) { 549 WARN_ON(!sbio->pagev[i]->page); 550 scrub_block_put(sbio->pagev[i]->sblock); 551 } 552 bio_put(sbio->bio); 553 } 554 555 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) { 556 struct scrub_bio *sbio = sctx->bios[i]; 557 558 if (!sbio) 559 break; 560 kfree(sbio); 561 } 562 563 kfree(sctx->wr_curr_bio); 564 scrub_free_csums(sctx); 565 kfree(sctx); 566 } 567 568 static void scrub_put_ctx(struct scrub_ctx *sctx) 569 { 570 if (refcount_dec_and_test(&sctx->refs)) 571 scrub_free_ctx(sctx); 572 } 573 574 static noinline_for_stack struct scrub_ctx *scrub_setup_ctx( 575 struct btrfs_fs_info *fs_info, int is_dev_replace) 576 { 577 struct scrub_ctx *sctx; 578 int i; 579 580 sctx = kzalloc(sizeof(*sctx), GFP_KERNEL); 581 if (!sctx) 582 goto nomem; 583 refcount_set(&sctx->refs, 1); 584 sctx->is_dev_replace = is_dev_replace; 585 sctx->pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO; 586 sctx->curr = -1; 587 sctx->fs_info = fs_info; 588 INIT_LIST_HEAD(&sctx->csum_list); 589 for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) { 590 struct scrub_bio *sbio; 591 592 sbio = kzalloc(sizeof(*sbio), GFP_KERNEL); 593 if (!sbio) 594 goto nomem; 595 sctx->bios[i] = sbio; 596 597 sbio->index = i; 598 sbio->sctx = sctx; 599 sbio->page_count = 0; 600 btrfs_init_work(&sbio->work, scrub_bio_end_io_worker, NULL, 601 NULL); 602 603 if (i != SCRUB_BIOS_PER_SCTX - 1) 604 sctx->bios[i]->next_free = i + 1; 605 else 606 sctx->bios[i]->next_free = -1; 607 } 608 sctx->first_free = 0; 609 atomic_set(&sctx->bios_in_flight, 0); 610 atomic_set(&sctx->workers_pending, 0); 611 atomic_set(&sctx->cancel_req, 0); 612 sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy); 613 614 spin_lock_init(&sctx->list_lock); 615 spin_lock_init(&sctx->stat_lock); 616 init_waitqueue_head(&sctx->list_wait); 617 618 WARN_ON(sctx->wr_curr_bio != NULL); 619 mutex_init(&sctx->wr_lock); 620 sctx->wr_curr_bio = NULL; 621 if (is_dev_replace) { 622 WARN_ON(!fs_info->dev_replace.tgtdev); 623 sctx->pages_per_wr_bio = SCRUB_PAGES_PER_WR_BIO; 624 sctx->wr_tgtdev = fs_info->dev_replace.tgtdev; 625 sctx->flush_all_writes = false; 626 } 627 628 return sctx; 629 630 nomem: 631 scrub_free_ctx(sctx); 632 return ERR_PTR(-ENOMEM); 633 } 634 635 static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, 636 void *warn_ctx) 637 { 638 u64 isize; 639 u32 nlink; 640 int ret; 641 int i; 642 unsigned nofs_flag; 643 struct extent_buffer *eb; 644 struct btrfs_inode_item *inode_item; 645 struct scrub_warning *swarn = warn_ctx; 646 struct btrfs_fs_info *fs_info = swarn->dev->fs_info; 647 struct inode_fs_paths *ipath = NULL; 648 struct btrfs_root *local_root; 649 struct btrfs_key root_key; 650 struct btrfs_key key; 651 652 root_key.objectid = root; 653 root_key.type = BTRFS_ROOT_ITEM_KEY; 654 root_key.offset = (u64)-1; 655 local_root = btrfs_read_fs_root_no_name(fs_info, &root_key); 656 if (IS_ERR(local_root)) { 657 ret = PTR_ERR(local_root); 658 goto err; 659 } 660 661 /* 662 * this makes the path point to (inum INODE_ITEM ioff) 663 */ 664 key.objectid = inum; 665 key.type = BTRFS_INODE_ITEM_KEY; 666 key.offset = 0; 667 668 ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0); 669 if (ret) { 670 btrfs_release_path(swarn->path); 671 goto err; 672 } 673 674 eb = swarn->path->nodes[0]; 675 inode_item = btrfs_item_ptr(eb, swarn->path->slots[0], 676 struct btrfs_inode_item); 677 isize = btrfs_inode_size(eb, inode_item); 678 nlink = btrfs_inode_nlink(eb, inode_item); 679 btrfs_release_path(swarn->path); 680 681 /* 682 * init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub 683 * uses GFP_NOFS in this context, so we keep it consistent but it does 684 * not seem to be strictly necessary. 685 */ 686 nofs_flag = memalloc_nofs_save(); 687 ipath = init_ipath(4096, local_root, swarn->path); 688 memalloc_nofs_restore(nofs_flag); 689 if (IS_ERR(ipath)) { 690 ret = PTR_ERR(ipath); 691 ipath = NULL; 692 goto err; 693 } 694 ret = paths_from_inode(inum, ipath); 695 696 if (ret < 0) 697 goto err; 698 699 /* 700 * we deliberately ignore the bit ipath might have been too small to 701 * hold all of the paths here 702 */ 703 for (i = 0; i < ipath->fspath->elem_cnt; ++i) 704 btrfs_warn_in_rcu(fs_info, 705 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %llu, links %u (path: %s)", 706 swarn->errstr, swarn->logical, 707 rcu_str_deref(swarn->dev->name), 708 swarn->physical, 709 root, inum, offset, 710 min(isize - offset, (u64)PAGE_SIZE), nlink, 711 (char *)(unsigned long)ipath->fspath->val[i]); 712 713 free_ipath(ipath); 714 return 0; 715 716 err: 717 btrfs_warn_in_rcu(fs_info, 718 "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d", 719 swarn->errstr, swarn->logical, 720 rcu_str_deref(swarn->dev->name), 721 swarn->physical, 722 root, inum, offset, ret); 723 724 free_ipath(ipath); 725 return 0; 726 } 727 728 static void scrub_print_warning(const char *errstr, struct scrub_block *sblock) 729 { 730 struct btrfs_device *dev; 731 struct btrfs_fs_info *fs_info; 732 struct btrfs_path *path; 733 struct btrfs_key found_key; 734 struct extent_buffer *eb; 735 struct btrfs_extent_item *ei; 736 struct scrub_warning swarn; 737 unsigned long ptr = 0; 738 u64 extent_item_pos; 739 u64 flags = 0; 740 u64 ref_root; 741 u32 item_size; 742 u8 ref_level = 0; 743 int ret; 744 745 WARN_ON(sblock->page_count < 1); 746 dev = sblock->pagev[0]->dev; 747 fs_info = sblock->sctx->fs_info; 748 749 path = btrfs_alloc_path(); 750 if (!path) 751 return; 752 753 swarn.physical = sblock->pagev[0]->physical; 754 swarn.logical = sblock->pagev[0]->logical; 755 swarn.errstr = errstr; 756 swarn.dev = NULL; 757 758 ret = extent_from_logical(fs_info, swarn.logical, path, &found_key, 759 &flags); 760 if (ret < 0) 761 goto out; 762 763 extent_item_pos = swarn.logical - found_key.objectid; 764 swarn.extent_item_size = found_key.offset; 765 766 eb = path->nodes[0]; 767 ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); 768 item_size = btrfs_item_size_nr(eb, path->slots[0]); 769 770 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 771 do { 772 ret = tree_backref_for_extent(&ptr, eb, &found_key, ei, 773 item_size, &ref_root, 774 &ref_level); 775 btrfs_warn_in_rcu(fs_info, 776 "%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu", 777 errstr, swarn.logical, 778 rcu_str_deref(dev->name), 779 swarn.physical, 780 ref_level ? "node" : "leaf", 781 ret < 0 ? -1 : ref_level, 782 ret < 0 ? -1 : ref_root); 783 } while (ret != 1); 784 btrfs_release_path(path); 785 } else { 786 btrfs_release_path(path); 787 swarn.path = path; 788 swarn.dev = dev; 789 iterate_extent_inodes(fs_info, found_key.objectid, 790 extent_item_pos, 1, 791 scrub_print_warning_inode, &swarn, false); 792 } 793 794 out: 795 btrfs_free_path(path); 796 } 797 798 static inline void scrub_get_recover(struct scrub_recover *recover) 799 { 800 refcount_inc(&recover->refs); 801 } 802 803 static inline void scrub_put_recover(struct btrfs_fs_info *fs_info, 804 struct scrub_recover *recover) 805 { 806 if (refcount_dec_and_test(&recover->refs)) { 807 btrfs_bio_counter_dec(fs_info); 808 btrfs_put_bbio(recover->bbio); 809 kfree(recover); 810 } 811 } 812 813 /* 814 * scrub_handle_errored_block gets called when either verification of the 815 * pages failed or the bio failed to read, e.g. with EIO. In the latter 816 * case, this function handles all pages in the bio, even though only one 817 * may be bad. 818 * The goal of this function is to repair the errored block by using the 819 * contents of one of the mirrors. 820 */ 821 static int scrub_handle_errored_block(struct scrub_block *sblock_to_check) 822 { 823 struct scrub_ctx *sctx = sblock_to_check->sctx; 824 struct btrfs_device *dev; 825 struct btrfs_fs_info *fs_info; 826 u64 logical; 827 unsigned int failed_mirror_index; 828 unsigned int is_metadata; 829 unsigned int have_csum; 830 struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */ 831 struct scrub_block *sblock_bad; 832 int ret; 833 int mirror_index; 834 int page_num; 835 int success; 836 bool full_stripe_locked; 837 unsigned int nofs_flag; 838 static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, 839 DEFAULT_RATELIMIT_BURST); 840 841 BUG_ON(sblock_to_check->page_count < 1); 842 fs_info = sctx->fs_info; 843 if (sblock_to_check->pagev[0]->flags & BTRFS_EXTENT_FLAG_SUPER) { 844 /* 845 * if we find an error in a super block, we just report it. 846 * They will get written with the next transaction commit 847 * anyway 848 */ 849 spin_lock(&sctx->stat_lock); 850 ++sctx->stat.super_errors; 851 spin_unlock(&sctx->stat_lock); 852 return 0; 853 } 854 logical = sblock_to_check->pagev[0]->logical; 855 BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1); 856 failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1; 857 is_metadata = !(sblock_to_check->pagev[0]->flags & 858 BTRFS_EXTENT_FLAG_DATA); 859 have_csum = sblock_to_check->pagev[0]->have_csum; 860 dev = sblock_to_check->pagev[0]->dev; 861 862 /* 863 * We must use GFP_NOFS because the scrub task might be waiting for a 864 * worker task executing this function and in turn a transaction commit 865 * might be waiting the scrub task to pause (which needs to wait for all 866 * the worker tasks to complete before pausing). 867 * We do allocations in the workers through insert_full_stripe_lock() 868 * and scrub_add_page_to_wr_bio(), which happens down the call chain of 869 * this function. 870 */ 871 nofs_flag = memalloc_nofs_save(); 872 /* 873 * For RAID5/6, race can happen for a different device scrub thread. 874 * For data corruption, Parity and Data threads will both try 875 * to recovery the data. 876 * Race can lead to doubly added csum error, or even unrecoverable 877 * error. 878 */ 879 ret = lock_full_stripe(fs_info, logical, &full_stripe_locked); 880 if (ret < 0) { 881 memalloc_nofs_restore(nofs_flag); 882 spin_lock(&sctx->stat_lock); 883 if (ret == -ENOMEM) 884 sctx->stat.malloc_errors++; 885 sctx->stat.read_errors++; 886 sctx->stat.uncorrectable_errors++; 887 spin_unlock(&sctx->stat_lock); 888 return ret; 889 } 890 891 /* 892 * read all mirrors one after the other. This includes to 893 * re-read the extent or metadata block that failed (that was 894 * the cause that this fixup code is called) another time, 895 * page by page this time in order to know which pages 896 * caused I/O errors and which ones are good (for all mirrors). 897 * It is the goal to handle the situation when more than one 898 * mirror contains I/O errors, but the errors do not 899 * overlap, i.e. the data can be repaired by selecting the 900 * pages from those mirrors without I/O error on the 901 * particular pages. One example (with blocks >= 2 * PAGE_SIZE) 902 * would be that mirror #1 has an I/O error on the first page, 903 * the second page is good, and mirror #2 has an I/O error on 904 * the second page, but the first page is good. 905 * Then the first page of the first mirror can be repaired by 906 * taking the first page of the second mirror, and the 907 * second page of the second mirror can be repaired by 908 * copying the contents of the 2nd page of the 1st mirror. 909 * One more note: if the pages of one mirror contain I/O 910 * errors, the checksum cannot be verified. In order to get 911 * the best data for repairing, the first attempt is to find 912 * a mirror without I/O errors and with a validated checksum. 913 * Only if this is not possible, the pages are picked from 914 * mirrors with I/O errors without considering the checksum. 915 * If the latter is the case, at the end, the checksum of the 916 * repaired area is verified in order to correctly maintain 917 * the statistics. 918 */ 919 920 sblocks_for_recheck = kcalloc(BTRFS_MAX_MIRRORS, 921 sizeof(*sblocks_for_recheck), GFP_KERNEL); 922 if (!sblocks_for_recheck) { 923 spin_lock(&sctx->stat_lock); 924 sctx->stat.malloc_errors++; 925 sctx->stat.read_errors++; 926 sctx->stat.uncorrectable_errors++; 927 spin_unlock(&sctx->stat_lock); 928 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); 929 goto out; 930 } 931 932 /* setup the context, map the logical blocks and alloc the pages */ 933 ret = scrub_setup_recheck_block(sblock_to_check, sblocks_for_recheck); 934 if (ret) { 935 spin_lock(&sctx->stat_lock); 936 sctx->stat.read_errors++; 937 sctx->stat.uncorrectable_errors++; 938 spin_unlock(&sctx->stat_lock); 939 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); 940 goto out; 941 } 942 BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS); 943 sblock_bad = sblocks_for_recheck + failed_mirror_index; 944 945 /* build and submit the bios for the failed mirror, check checksums */ 946 scrub_recheck_block(fs_info, sblock_bad, 1); 947 948 if (!sblock_bad->header_error && !sblock_bad->checksum_error && 949 sblock_bad->no_io_error_seen) { 950 /* 951 * the error disappeared after reading page by page, or 952 * the area was part of a huge bio and other parts of the 953 * bio caused I/O errors, or the block layer merged several 954 * read requests into one and the error is caused by a 955 * different bio (usually one of the two latter cases is 956 * the cause) 957 */ 958 spin_lock(&sctx->stat_lock); 959 sctx->stat.unverified_errors++; 960 sblock_to_check->data_corrected = 1; 961 spin_unlock(&sctx->stat_lock); 962 963 if (sctx->is_dev_replace) 964 scrub_write_block_to_dev_replace(sblock_bad); 965 goto out; 966 } 967 968 if (!sblock_bad->no_io_error_seen) { 969 spin_lock(&sctx->stat_lock); 970 sctx->stat.read_errors++; 971 spin_unlock(&sctx->stat_lock); 972 if (__ratelimit(&_rs)) 973 scrub_print_warning("i/o error", sblock_to_check); 974 btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); 975 } else if (sblock_bad->checksum_error) { 976 spin_lock(&sctx->stat_lock); 977 sctx->stat.csum_errors++; 978 spin_unlock(&sctx->stat_lock); 979 if (__ratelimit(&_rs)) 980 scrub_print_warning("checksum error", sblock_to_check); 981 btrfs_dev_stat_inc_and_print(dev, 982 BTRFS_DEV_STAT_CORRUPTION_ERRS); 983 } else if (sblock_bad->header_error) { 984 spin_lock(&sctx->stat_lock); 985 sctx->stat.verify_errors++; 986 spin_unlock(&sctx->stat_lock); 987 if (__ratelimit(&_rs)) 988 scrub_print_warning("checksum/header error", 989 sblock_to_check); 990 if (sblock_bad->generation_error) 991 btrfs_dev_stat_inc_and_print(dev, 992 BTRFS_DEV_STAT_GENERATION_ERRS); 993 else 994 btrfs_dev_stat_inc_and_print(dev, 995 BTRFS_DEV_STAT_CORRUPTION_ERRS); 996 } 997 998 if (sctx->readonly) { 999 ASSERT(!sctx->is_dev_replace); 1000 goto out; 1001 } 1002 1003 /* 1004 * now build and submit the bios for the other mirrors, check 1005 * checksums. 1006 * First try to pick the mirror which is completely without I/O 1007 * errors and also does not have a checksum error. 1008 * If one is found, and if a checksum is present, the full block 1009 * that is known to contain an error is rewritten. Afterwards 1010 * the block is known to be corrected. 1011 * If a mirror is found which is completely correct, and no 1012 * checksum is present, only those pages are rewritten that had 1013 * an I/O error in the block to be repaired, since it cannot be 1014 * determined, which copy of the other pages is better (and it 1015 * could happen otherwise that a correct page would be 1016 * overwritten by a bad one). 1017 */ 1018 for (mirror_index = 0; ;mirror_index++) { 1019 struct scrub_block *sblock_other; 1020 1021 if (mirror_index == failed_mirror_index) 1022 continue; 1023 1024 /* raid56's mirror can be more than BTRFS_MAX_MIRRORS */ 1025 if (!scrub_is_page_on_raid56(sblock_bad->pagev[0])) { 1026 if (mirror_index >= BTRFS_MAX_MIRRORS) 1027 break; 1028 if (!sblocks_for_recheck[mirror_index].page_count) 1029 break; 1030 1031 sblock_other = sblocks_for_recheck + mirror_index; 1032 } else { 1033 struct scrub_recover *r = sblock_bad->pagev[0]->recover; 1034 int max_allowed = r->bbio->num_stripes - 1035 r->bbio->num_tgtdevs; 1036 1037 if (mirror_index >= max_allowed) 1038 break; 1039 if (!sblocks_for_recheck[1].page_count) 1040 break; 1041 1042 ASSERT(failed_mirror_index == 0); 1043 sblock_other = sblocks_for_recheck + 1; 1044 sblock_other->pagev[0]->mirror_num = 1 + mirror_index; 1045 } 1046 1047 /* build and submit the bios, check checksums */ 1048 scrub_recheck_block(fs_info, sblock_other, 0); 1049 1050 if (!sblock_other->header_error && 1051 !sblock_other->checksum_error && 1052 sblock_other->no_io_error_seen) { 1053 if (sctx->is_dev_replace) { 1054 scrub_write_block_to_dev_replace(sblock_other); 1055 goto corrected_error; 1056 } else { 1057 ret = scrub_repair_block_from_good_copy( 1058 sblock_bad, sblock_other); 1059 if (!ret) 1060 goto corrected_error; 1061 } 1062 } 1063 } 1064 1065 if (sblock_bad->no_io_error_seen && !sctx->is_dev_replace) 1066 goto did_not_correct_error; 1067 1068 /* 1069 * In case of I/O errors in the area that is supposed to be 1070 * repaired, continue by picking good copies of those pages. 1071 * Select the good pages from mirrors to rewrite bad pages from 1072 * the area to fix. Afterwards verify the checksum of the block 1073 * that is supposed to be repaired. This verification step is 1074 * only done for the purpose of statistic counting and for the 1075 * final scrub report, whether errors remain. 1076 * A perfect algorithm could make use of the checksum and try 1077 * all possible combinations of pages from the different mirrors 1078 * until the checksum verification succeeds. For example, when 1079 * the 2nd page of mirror #1 faces I/O errors, and the 2nd page 1080 * of mirror #2 is readable but the final checksum test fails, 1081 * then the 2nd page of mirror #3 could be tried, whether now 1082 * the final checksum succeeds. But this would be a rare 1083 * exception and is therefore not implemented. At least it is 1084 * avoided that the good copy is overwritten. 1085 * A more useful improvement would be to pick the sectors 1086 * without I/O error based on sector sizes (512 bytes on legacy 1087 * disks) instead of on PAGE_SIZE. Then maybe 512 byte of one 1088 * mirror could be repaired by taking 512 byte of a different 1089 * mirror, even if other 512 byte sectors in the same PAGE_SIZE 1090 * area are unreadable. 1091 */ 1092 success = 1; 1093 for (page_num = 0; page_num < sblock_bad->page_count; 1094 page_num++) { 1095 struct scrub_page *page_bad = sblock_bad->pagev[page_num]; 1096 struct scrub_block *sblock_other = NULL; 1097 1098 /* skip no-io-error page in scrub */ 1099 if (!page_bad->io_error && !sctx->is_dev_replace) 1100 continue; 1101 1102 if (scrub_is_page_on_raid56(sblock_bad->pagev[0])) { 1103 /* 1104 * In case of dev replace, if raid56 rebuild process 1105 * didn't work out correct data, then copy the content 1106 * in sblock_bad to make sure target device is identical 1107 * to source device, instead of writing garbage data in 1108 * sblock_for_recheck array to target device. 1109 */ 1110 sblock_other = NULL; 1111 } else if (page_bad->io_error) { 1112 /* try to find no-io-error page in mirrors */ 1113 for (mirror_index = 0; 1114 mirror_index < BTRFS_MAX_MIRRORS && 1115 sblocks_for_recheck[mirror_index].page_count > 0; 1116 mirror_index++) { 1117 if (!sblocks_for_recheck[mirror_index]. 1118 pagev[page_num]->io_error) { 1119 sblock_other = sblocks_for_recheck + 1120 mirror_index; 1121 break; 1122 } 1123 } 1124 if (!sblock_other) 1125 success = 0; 1126 } 1127 1128 if (sctx->is_dev_replace) { 1129 /* 1130 * did not find a mirror to fetch the page 1131 * from. scrub_write_page_to_dev_replace() 1132 * handles this case (page->io_error), by 1133 * filling the block with zeros before 1134 * submitting the write request 1135 */ 1136 if (!sblock_other) 1137 sblock_other = sblock_bad; 1138 1139 if (scrub_write_page_to_dev_replace(sblock_other, 1140 page_num) != 0) { 1141 atomic64_inc( 1142 &fs_info->dev_replace.num_write_errors); 1143 success = 0; 1144 } 1145 } else if (sblock_other) { 1146 ret = scrub_repair_page_from_good_copy(sblock_bad, 1147 sblock_other, 1148 page_num, 0); 1149 if (0 == ret) 1150 page_bad->io_error = 0; 1151 else 1152 success = 0; 1153 } 1154 } 1155 1156 if (success && !sctx->is_dev_replace) { 1157 if (is_metadata || have_csum) { 1158 /* 1159 * need to verify the checksum now that all 1160 * sectors on disk are repaired (the write 1161 * request for data to be repaired is on its way). 1162 * Just be lazy and use scrub_recheck_block() 1163 * which re-reads the data before the checksum 1164 * is verified, but most likely the data comes out 1165 * of the page cache. 1166 */ 1167 scrub_recheck_block(fs_info, sblock_bad, 1); 1168 if (!sblock_bad->header_error && 1169 !sblock_bad->checksum_error && 1170 sblock_bad->no_io_error_seen) 1171 goto corrected_error; 1172 else 1173 goto did_not_correct_error; 1174 } else { 1175 corrected_error: 1176 spin_lock(&sctx->stat_lock); 1177 sctx->stat.corrected_errors++; 1178 sblock_to_check->data_corrected = 1; 1179 spin_unlock(&sctx->stat_lock); 1180 btrfs_err_rl_in_rcu(fs_info, 1181 "fixed up error at logical %llu on dev %s", 1182 logical, rcu_str_deref(dev->name)); 1183 } 1184 } else { 1185 did_not_correct_error: 1186 spin_lock(&sctx->stat_lock); 1187 sctx->stat.uncorrectable_errors++; 1188 spin_unlock(&sctx->stat_lock); 1189 btrfs_err_rl_in_rcu(fs_info, 1190 "unable to fixup (regular) error at logical %llu on dev %s", 1191 logical, rcu_str_deref(dev->name)); 1192 } 1193 1194 out: 1195 if (sblocks_for_recheck) { 1196 for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS; 1197 mirror_index++) { 1198 struct scrub_block *sblock = sblocks_for_recheck + 1199 mirror_index; 1200 struct scrub_recover *recover; 1201 int page_index; 1202 1203 for (page_index = 0; page_index < sblock->page_count; 1204 page_index++) { 1205 sblock->pagev[page_index]->sblock = NULL; 1206 recover = sblock->pagev[page_index]->recover; 1207 if (recover) { 1208 scrub_put_recover(fs_info, recover); 1209 sblock->pagev[page_index]->recover = 1210 NULL; 1211 } 1212 scrub_page_put(sblock->pagev[page_index]); 1213 } 1214 } 1215 kfree(sblocks_for_recheck); 1216 } 1217 1218 ret = unlock_full_stripe(fs_info, logical, full_stripe_locked); 1219 memalloc_nofs_restore(nofs_flag); 1220 if (ret < 0) 1221 return ret; 1222 return 0; 1223 } 1224 1225 static inline int scrub_nr_raid_mirrors(struct btrfs_bio *bbio) 1226 { 1227 if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID5) 1228 return 2; 1229 else if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID6) 1230 return 3; 1231 else 1232 return (int)bbio->num_stripes; 1233 } 1234 1235 static inline void scrub_stripe_index_and_offset(u64 logical, u64 map_type, 1236 u64 *raid_map, 1237 u64 mapped_length, 1238 int nstripes, int mirror, 1239 int *stripe_index, 1240 u64 *stripe_offset) 1241 { 1242 int i; 1243 1244 if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 1245 /* RAID5/6 */ 1246 for (i = 0; i < nstripes; i++) { 1247 if (raid_map[i] == RAID6_Q_STRIPE || 1248 raid_map[i] == RAID5_P_STRIPE) 1249 continue; 1250 1251 if (logical >= raid_map[i] && 1252 logical < raid_map[i] + mapped_length) 1253 break; 1254 } 1255 1256 *stripe_index = i; 1257 *stripe_offset = logical - raid_map[i]; 1258 } else { 1259 /* The other RAID type */ 1260 *stripe_index = mirror; 1261 *stripe_offset = 0; 1262 } 1263 } 1264 1265 static int scrub_setup_recheck_block(struct scrub_block *original_sblock, 1266 struct scrub_block *sblocks_for_recheck) 1267 { 1268 struct scrub_ctx *sctx = original_sblock->sctx; 1269 struct btrfs_fs_info *fs_info = sctx->fs_info; 1270 u64 length = original_sblock->page_count * PAGE_SIZE; 1271 u64 logical = original_sblock->pagev[0]->logical; 1272 u64 generation = original_sblock->pagev[0]->generation; 1273 u64 flags = original_sblock->pagev[0]->flags; 1274 u64 have_csum = original_sblock->pagev[0]->have_csum; 1275 struct scrub_recover *recover; 1276 struct btrfs_bio *bbio; 1277 u64 sublen; 1278 u64 mapped_length; 1279 u64 stripe_offset; 1280 int stripe_index; 1281 int page_index = 0; 1282 int mirror_index; 1283 int nmirrors; 1284 int ret; 1285 1286 /* 1287 * note: the two members refs and outstanding_pages 1288 * are not used (and not set) in the blocks that are used for 1289 * the recheck procedure 1290 */ 1291 1292 while (length > 0) { 1293 sublen = min_t(u64, length, PAGE_SIZE); 1294 mapped_length = sublen; 1295 bbio = NULL; 1296 1297 /* 1298 * with a length of PAGE_SIZE, each returned stripe 1299 * represents one mirror 1300 */ 1301 btrfs_bio_counter_inc_blocked(fs_info); 1302 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, 1303 logical, &mapped_length, &bbio); 1304 if (ret || !bbio || mapped_length < sublen) { 1305 btrfs_put_bbio(bbio); 1306 btrfs_bio_counter_dec(fs_info); 1307 return -EIO; 1308 } 1309 1310 recover = kzalloc(sizeof(struct scrub_recover), GFP_NOFS); 1311 if (!recover) { 1312 btrfs_put_bbio(bbio); 1313 btrfs_bio_counter_dec(fs_info); 1314 return -ENOMEM; 1315 } 1316 1317 refcount_set(&recover->refs, 1); 1318 recover->bbio = bbio; 1319 recover->map_length = mapped_length; 1320 1321 BUG_ON(page_index >= SCRUB_MAX_PAGES_PER_BLOCK); 1322 1323 nmirrors = min(scrub_nr_raid_mirrors(bbio), BTRFS_MAX_MIRRORS); 1324 1325 for (mirror_index = 0; mirror_index < nmirrors; 1326 mirror_index++) { 1327 struct scrub_block *sblock; 1328 struct scrub_page *page; 1329 1330 sblock = sblocks_for_recheck + mirror_index; 1331 sblock->sctx = sctx; 1332 1333 page = kzalloc(sizeof(*page), GFP_NOFS); 1334 if (!page) { 1335 leave_nomem: 1336 spin_lock(&sctx->stat_lock); 1337 sctx->stat.malloc_errors++; 1338 spin_unlock(&sctx->stat_lock); 1339 scrub_put_recover(fs_info, recover); 1340 return -ENOMEM; 1341 } 1342 scrub_page_get(page); 1343 sblock->pagev[page_index] = page; 1344 page->sblock = sblock; 1345 page->flags = flags; 1346 page->generation = generation; 1347 page->logical = logical; 1348 page->have_csum = have_csum; 1349 if (have_csum) 1350 memcpy(page->csum, 1351 original_sblock->pagev[0]->csum, 1352 sctx->csum_size); 1353 1354 scrub_stripe_index_and_offset(logical, 1355 bbio->map_type, 1356 bbio->raid_map, 1357 mapped_length, 1358 bbio->num_stripes - 1359 bbio->num_tgtdevs, 1360 mirror_index, 1361 &stripe_index, 1362 &stripe_offset); 1363 page->physical = bbio->stripes[stripe_index].physical + 1364 stripe_offset; 1365 page->dev = bbio->stripes[stripe_index].dev; 1366 1367 BUG_ON(page_index >= original_sblock->page_count); 1368 page->physical_for_dev_replace = 1369 original_sblock->pagev[page_index]-> 1370 physical_for_dev_replace; 1371 /* for missing devices, dev->bdev is NULL */ 1372 page->mirror_num = mirror_index + 1; 1373 sblock->page_count++; 1374 page->page = alloc_page(GFP_NOFS); 1375 if (!page->page) 1376 goto leave_nomem; 1377 1378 scrub_get_recover(recover); 1379 page->recover = recover; 1380 } 1381 scrub_put_recover(fs_info, recover); 1382 length -= sublen; 1383 logical += sublen; 1384 page_index++; 1385 } 1386 1387 return 0; 1388 } 1389 1390 static void scrub_bio_wait_endio(struct bio *bio) 1391 { 1392 complete(bio->bi_private); 1393 } 1394 1395 static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info, 1396 struct bio *bio, 1397 struct scrub_page *page) 1398 { 1399 DECLARE_COMPLETION_ONSTACK(done); 1400 int ret; 1401 int mirror_num; 1402 1403 bio->bi_iter.bi_sector = page->logical >> 9; 1404 bio->bi_private = &done; 1405 bio->bi_end_io = scrub_bio_wait_endio; 1406 1407 mirror_num = page->sblock->pagev[0]->mirror_num; 1408 ret = raid56_parity_recover(fs_info, bio, page->recover->bbio, 1409 page->recover->map_length, 1410 mirror_num, 0); 1411 if (ret) 1412 return ret; 1413 1414 wait_for_completion_io(&done); 1415 return blk_status_to_errno(bio->bi_status); 1416 } 1417 1418 static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info, 1419 struct scrub_block *sblock) 1420 { 1421 struct scrub_page *first_page = sblock->pagev[0]; 1422 struct bio *bio; 1423 int page_num; 1424 1425 /* All pages in sblock belong to the same stripe on the same device. */ 1426 ASSERT(first_page->dev); 1427 if (!first_page->dev->bdev) 1428 goto out; 1429 1430 bio = btrfs_io_bio_alloc(BIO_MAX_PAGES); 1431 bio_set_dev(bio, first_page->dev->bdev); 1432 1433 for (page_num = 0; page_num < sblock->page_count; page_num++) { 1434 struct scrub_page *page = sblock->pagev[page_num]; 1435 1436 WARN_ON(!page->page); 1437 bio_add_page(bio, page->page, PAGE_SIZE, 0); 1438 } 1439 1440 if (scrub_submit_raid56_bio_wait(fs_info, bio, first_page)) { 1441 bio_put(bio); 1442 goto out; 1443 } 1444 1445 bio_put(bio); 1446 1447 scrub_recheck_block_checksum(sblock); 1448 1449 return; 1450 out: 1451 for (page_num = 0; page_num < sblock->page_count; page_num++) 1452 sblock->pagev[page_num]->io_error = 1; 1453 1454 sblock->no_io_error_seen = 0; 1455 } 1456 1457 /* 1458 * this function will check the on disk data for checksum errors, header 1459 * errors and read I/O errors. If any I/O errors happen, the exact pages 1460 * which are errored are marked as being bad. The goal is to enable scrub 1461 * to take those pages that are not errored from all the mirrors so that 1462 * the pages that are errored in the just handled mirror can be repaired. 1463 */ 1464 static void scrub_recheck_block(struct btrfs_fs_info *fs_info, 1465 struct scrub_block *sblock, 1466 int retry_failed_mirror) 1467 { 1468 int page_num; 1469 1470 sblock->no_io_error_seen = 1; 1471 1472 /* short cut for raid56 */ 1473 if (!retry_failed_mirror && scrub_is_page_on_raid56(sblock->pagev[0])) 1474 return scrub_recheck_block_on_raid56(fs_info, sblock); 1475 1476 for (page_num = 0; page_num < sblock->page_count; page_num++) { 1477 struct bio *bio; 1478 struct scrub_page *page = sblock->pagev[page_num]; 1479 1480 if (page->dev->bdev == NULL) { 1481 page->io_error = 1; 1482 sblock->no_io_error_seen = 0; 1483 continue; 1484 } 1485 1486 WARN_ON(!page->page); 1487 bio = btrfs_io_bio_alloc(1); 1488 bio_set_dev(bio, page->dev->bdev); 1489 1490 bio_add_page(bio, page->page, PAGE_SIZE, 0); 1491 bio->bi_iter.bi_sector = page->physical >> 9; 1492 bio->bi_opf = REQ_OP_READ; 1493 1494 if (btrfsic_submit_bio_wait(bio)) { 1495 page->io_error = 1; 1496 sblock->no_io_error_seen = 0; 1497 } 1498 1499 bio_put(bio); 1500 } 1501 1502 if (sblock->no_io_error_seen) 1503 scrub_recheck_block_checksum(sblock); 1504 } 1505 1506 static inline int scrub_check_fsid(u8 fsid[], 1507 struct scrub_page *spage) 1508 { 1509 struct btrfs_fs_devices *fs_devices = spage->dev->fs_devices; 1510 int ret; 1511 1512 ret = memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE); 1513 return !ret; 1514 } 1515 1516 static void scrub_recheck_block_checksum(struct scrub_block *sblock) 1517 { 1518 sblock->header_error = 0; 1519 sblock->checksum_error = 0; 1520 sblock->generation_error = 0; 1521 1522 if (sblock->pagev[0]->flags & BTRFS_EXTENT_FLAG_DATA) 1523 scrub_checksum_data(sblock); 1524 else 1525 scrub_checksum_tree_block(sblock); 1526 } 1527 1528 static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, 1529 struct scrub_block *sblock_good) 1530 { 1531 int page_num; 1532 int ret = 0; 1533 1534 for (page_num = 0; page_num < sblock_bad->page_count; page_num++) { 1535 int ret_sub; 1536 1537 ret_sub = scrub_repair_page_from_good_copy(sblock_bad, 1538 sblock_good, 1539 page_num, 1); 1540 if (ret_sub) 1541 ret = ret_sub; 1542 } 1543 1544 return ret; 1545 } 1546 1547 static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad, 1548 struct scrub_block *sblock_good, 1549 int page_num, int force_write) 1550 { 1551 struct scrub_page *page_bad = sblock_bad->pagev[page_num]; 1552 struct scrub_page *page_good = sblock_good->pagev[page_num]; 1553 struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info; 1554 1555 BUG_ON(page_bad->page == NULL); 1556 BUG_ON(page_good->page == NULL); 1557 if (force_write || sblock_bad->header_error || 1558 sblock_bad->checksum_error || page_bad->io_error) { 1559 struct bio *bio; 1560 int ret; 1561 1562 if (!page_bad->dev->bdev) { 1563 btrfs_warn_rl(fs_info, 1564 "scrub_repair_page_from_good_copy(bdev == NULL) is unexpected"); 1565 return -EIO; 1566 } 1567 1568 bio = btrfs_io_bio_alloc(1); 1569 bio_set_dev(bio, page_bad->dev->bdev); 1570 bio->bi_iter.bi_sector = page_bad->physical >> 9; 1571 bio->bi_opf = REQ_OP_WRITE; 1572 1573 ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0); 1574 if (PAGE_SIZE != ret) { 1575 bio_put(bio); 1576 return -EIO; 1577 } 1578 1579 if (btrfsic_submit_bio_wait(bio)) { 1580 btrfs_dev_stat_inc_and_print(page_bad->dev, 1581 BTRFS_DEV_STAT_WRITE_ERRS); 1582 atomic64_inc(&fs_info->dev_replace.num_write_errors); 1583 bio_put(bio); 1584 return -EIO; 1585 } 1586 bio_put(bio); 1587 } 1588 1589 return 0; 1590 } 1591 1592 static void scrub_write_block_to_dev_replace(struct scrub_block *sblock) 1593 { 1594 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info; 1595 int page_num; 1596 1597 /* 1598 * This block is used for the check of the parity on the source device, 1599 * so the data needn't be written into the destination device. 1600 */ 1601 if (sblock->sparity) 1602 return; 1603 1604 for (page_num = 0; page_num < sblock->page_count; page_num++) { 1605 int ret; 1606 1607 ret = scrub_write_page_to_dev_replace(sblock, page_num); 1608 if (ret) 1609 atomic64_inc(&fs_info->dev_replace.num_write_errors); 1610 } 1611 } 1612 1613 static int scrub_write_page_to_dev_replace(struct scrub_block *sblock, 1614 int page_num) 1615 { 1616 struct scrub_page *spage = sblock->pagev[page_num]; 1617 1618 BUG_ON(spage->page == NULL); 1619 if (spage->io_error) { 1620 void *mapped_buffer = kmap_atomic(spage->page); 1621 1622 clear_page(mapped_buffer); 1623 flush_dcache_page(spage->page); 1624 kunmap_atomic(mapped_buffer); 1625 } 1626 return scrub_add_page_to_wr_bio(sblock->sctx, spage); 1627 } 1628 1629 static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx, 1630 struct scrub_page *spage) 1631 { 1632 struct scrub_bio *sbio; 1633 int ret; 1634 1635 mutex_lock(&sctx->wr_lock); 1636 again: 1637 if (!sctx->wr_curr_bio) { 1638 sctx->wr_curr_bio = kzalloc(sizeof(*sctx->wr_curr_bio), 1639 GFP_KERNEL); 1640 if (!sctx->wr_curr_bio) { 1641 mutex_unlock(&sctx->wr_lock); 1642 return -ENOMEM; 1643 } 1644 sctx->wr_curr_bio->sctx = sctx; 1645 sctx->wr_curr_bio->page_count = 0; 1646 } 1647 sbio = sctx->wr_curr_bio; 1648 if (sbio->page_count == 0) { 1649 struct bio *bio; 1650 1651 sbio->physical = spage->physical_for_dev_replace; 1652 sbio->logical = spage->logical; 1653 sbio->dev = sctx->wr_tgtdev; 1654 bio = sbio->bio; 1655 if (!bio) { 1656 bio = btrfs_io_bio_alloc(sctx->pages_per_wr_bio); 1657 sbio->bio = bio; 1658 } 1659 1660 bio->bi_private = sbio; 1661 bio->bi_end_io = scrub_wr_bio_end_io; 1662 bio_set_dev(bio, sbio->dev->bdev); 1663 bio->bi_iter.bi_sector = sbio->physical >> 9; 1664 bio->bi_opf = REQ_OP_WRITE; 1665 sbio->status = 0; 1666 } else if (sbio->physical + sbio->page_count * PAGE_SIZE != 1667 spage->physical_for_dev_replace || 1668 sbio->logical + sbio->page_count * PAGE_SIZE != 1669 spage->logical) { 1670 scrub_wr_submit(sctx); 1671 goto again; 1672 } 1673 1674 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0); 1675 if (ret != PAGE_SIZE) { 1676 if (sbio->page_count < 1) { 1677 bio_put(sbio->bio); 1678 sbio->bio = NULL; 1679 mutex_unlock(&sctx->wr_lock); 1680 return -EIO; 1681 } 1682 scrub_wr_submit(sctx); 1683 goto again; 1684 } 1685 1686 sbio->pagev[sbio->page_count] = spage; 1687 scrub_page_get(spage); 1688 sbio->page_count++; 1689 if (sbio->page_count == sctx->pages_per_wr_bio) 1690 scrub_wr_submit(sctx); 1691 mutex_unlock(&sctx->wr_lock); 1692 1693 return 0; 1694 } 1695 1696 static void scrub_wr_submit(struct scrub_ctx *sctx) 1697 { 1698 struct scrub_bio *sbio; 1699 1700 if (!sctx->wr_curr_bio) 1701 return; 1702 1703 sbio = sctx->wr_curr_bio; 1704 sctx->wr_curr_bio = NULL; 1705 WARN_ON(!sbio->bio->bi_disk); 1706 scrub_pending_bio_inc(sctx); 1707 /* process all writes in a single worker thread. Then the block layer 1708 * orders the requests before sending them to the driver which 1709 * doubled the write performance on spinning disks when measured 1710 * with Linux 3.5 */ 1711 btrfsic_submit_bio(sbio->bio); 1712 } 1713 1714 static void scrub_wr_bio_end_io(struct bio *bio) 1715 { 1716 struct scrub_bio *sbio = bio->bi_private; 1717 struct btrfs_fs_info *fs_info = sbio->dev->fs_info; 1718 1719 sbio->status = bio->bi_status; 1720 sbio->bio = bio; 1721 1722 btrfs_init_work(&sbio->work, scrub_wr_bio_end_io_worker, NULL, NULL); 1723 btrfs_queue_work(fs_info->scrub_wr_completion_workers, &sbio->work); 1724 } 1725 1726 static void scrub_wr_bio_end_io_worker(struct btrfs_work *work) 1727 { 1728 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); 1729 struct scrub_ctx *sctx = sbio->sctx; 1730 int i; 1731 1732 WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO); 1733 if (sbio->status) { 1734 struct btrfs_dev_replace *dev_replace = 1735 &sbio->sctx->fs_info->dev_replace; 1736 1737 for (i = 0; i < sbio->page_count; i++) { 1738 struct scrub_page *spage = sbio->pagev[i]; 1739 1740 spage->io_error = 1; 1741 atomic64_inc(&dev_replace->num_write_errors); 1742 } 1743 } 1744 1745 for (i = 0; i < sbio->page_count; i++) 1746 scrub_page_put(sbio->pagev[i]); 1747 1748 bio_put(sbio->bio); 1749 kfree(sbio); 1750 scrub_pending_bio_dec(sctx); 1751 } 1752 1753 static int scrub_checksum(struct scrub_block *sblock) 1754 { 1755 u64 flags; 1756 int ret; 1757 1758 /* 1759 * No need to initialize these stats currently, 1760 * because this function only use return value 1761 * instead of these stats value. 1762 * 1763 * Todo: 1764 * always use stats 1765 */ 1766 sblock->header_error = 0; 1767 sblock->generation_error = 0; 1768 sblock->checksum_error = 0; 1769 1770 WARN_ON(sblock->page_count < 1); 1771 flags = sblock->pagev[0]->flags; 1772 ret = 0; 1773 if (flags & BTRFS_EXTENT_FLAG_DATA) 1774 ret = scrub_checksum_data(sblock); 1775 else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) 1776 ret = scrub_checksum_tree_block(sblock); 1777 else if (flags & BTRFS_EXTENT_FLAG_SUPER) 1778 (void)scrub_checksum_super(sblock); 1779 else 1780 WARN_ON(1); 1781 if (ret) 1782 scrub_handle_errored_block(sblock); 1783 1784 return ret; 1785 } 1786 1787 static int scrub_checksum_data(struct scrub_block *sblock) 1788 { 1789 struct scrub_ctx *sctx = sblock->sctx; 1790 struct btrfs_fs_info *fs_info = sctx->fs_info; 1791 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1792 u8 csum[BTRFS_CSUM_SIZE]; 1793 u8 *on_disk_csum; 1794 struct page *page; 1795 void *buffer; 1796 u64 len; 1797 int index; 1798 1799 BUG_ON(sblock->page_count < 1); 1800 if (!sblock->pagev[0]->have_csum) 1801 return 0; 1802 1803 shash->tfm = fs_info->csum_shash; 1804 crypto_shash_init(shash); 1805 1806 on_disk_csum = sblock->pagev[0]->csum; 1807 page = sblock->pagev[0]->page; 1808 buffer = kmap_atomic(page); 1809 1810 len = sctx->fs_info->sectorsize; 1811 index = 0; 1812 for (;;) { 1813 u64 l = min_t(u64, len, PAGE_SIZE); 1814 1815 crypto_shash_update(shash, buffer, l); 1816 kunmap_atomic(buffer); 1817 len -= l; 1818 if (len == 0) 1819 break; 1820 index++; 1821 BUG_ON(index >= sblock->page_count); 1822 BUG_ON(!sblock->pagev[index]->page); 1823 page = sblock->pagev[index]->page; 1824 buffer = kmap_atomic(page); 1825 } 1826 1827 crypto_shash_final(shash, csum); 1828 if (memcmp(csum, on_disk_csum, sctx->csum_size)) 1829 sblock->checksum_error = 1; 1830 1831 return sblock->checksum_error; 1832 } 1833 1834 static int scrub_checksum_tree_block(struct scrub_block *sblock) 1835 { 1836 struct scrub_ctx *sctx = sblock->sctx; 1837 struct btrfs_header *h; 1838 struct btrfs_fs_info *fs_info = sctx->fs_info; 1839 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1840 u8 calculated_csum[BTRFS_CSUM_SIZE]; 1841 u8 on_disk_csum[BTRFS_CSUM_SIZE]; 1842 struct page *page; 1843 void *mapped_buffer; 1844 u64 mapped_size; 1845 void *p; 1846 u64 len; 1847 int index; 1848 1849 shash->tfm = fs_info->csum_shash; 1850 crypto_shash_init(shash); 1851 1852 BUG_ON(sblock->page_count < 1); 1853 page = sblock->pagev[0]->page; 1854 mapped_buffer = kmap_atomic(page); 1855 h = (struct btrfs_header *)mapped_buffer; 1856 memcpy(on_disk_csum, h->csum, sctx->csum_size); 1857 1858 /* 1859 * we don't use the getter functions here, as we 1860 * a) don't have an extent buffer and 1861 * b) the page is already kmapped 1862 */ 1863 if (sblock->pagev[0]->logical != btrfs_stack_header_bytenr(h)) 1864 sblock->header_error = 1; 1865 1866 if (sblock->pagev[0]->generation != btrfs_stack_header_generation(h)) { 1867 sblock->header_error = 1; 1868 sblock->generation_error = 1; 1869 } 1870 1871 if (!scrub_check_fsid(h->fsid, sblock->pagev[0])) 1872 sblock->header_error = 1; 1873 1874 if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, 1875 BTRFS_UUID_SIZE)) 1876 sblock->header_error = 1; 1877 1878 len = sctx->fs_info->nodesize - BTRFS_CSUM_SIZE; 1879 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE; 1880 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE; 1881 index = 0; 1882 for (;;) { 1883 u64 l = min_t(u64, len, mapped_size); 1884 1885 crypto_shash_update(shash, p, l); 1886 kunmap_atomic(mapped_buffer); 1887 len -= l; 1888 if (len == 0) 1889 break; 1890 index++; 1891 BUG_ON(index >= sblock->page_count); 1892 BUG_ON(!sblock->pagev[index]->page); 1893 page = sblock->pagev[index]->page; 1894 mapped_buffer = kmap_atomic(page); 1895 mapped_size = PAGE_SIZE; 1896 p = mapped_buffer; 1897 } 1898 1899 crypto_shash_final(shash, calculated_csum); 1900 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size)) 1901 sblock->checksum_error = 1; 1902 1903 return sblock->header_error || sblock->checksum_error; 1904 } 1905 1906 static int scrub_checksum_super(struct scrub_block *sblock) 1907 { 1908 struct btrfs_super_block *s; 1909 struct scrub_ctx *sctx = sblock->sctx; 1910 struct btrfs_fs_info *fs_info = sctx->fs_info; 1911 SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); 1912 u8 calculated_csum[BTRFS_CSUM_SIZE]; 1913 u8 on_disk_csum[BTRFS_CSUM_SIZE]; 1914 struct page *page; 1915 void *mapped_buffer; 1916 u64 mapped_size; 1917 void *p; 1918 int fail_gen = 0; 1919 int fail_cor = 0; 1920 u64 len; 1921 int index; 1922 1923 shash->tfm = fs_info->csum_shash; 1924 crypto_shash_init(shash); 1925 1926 BUG_ON(sblock->page_count < 1); 1927 page = sblock->pagev[0]->page; 1928 mapped_buffer = kmap_atomic(page); 1929 s = (struct btrfs_super_block *)mapped_buffer; 1930 memcpy(on_disk_csum, s->csum, sctx->csum_size); 1931 1932 if (sblock->pagev[0]->logical != btrfs_super_bytenr(s)) 1933 ++fail_cor; 1934 1935 if (sblock->pagev[0]->generation != btrfs_super_generation(s)) 1936 ++fail_gen; 1937 1938 if (!scrub_check_fsid(s->fsid, sblock->pagev[0])) 1939 ++fail_cor; 1940 1941 len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE; 1942 mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE; 1943 p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE; 1944 index = 0; 1945 for (;;) { 1946 u64 l = min_t(u64, len, mapped_size); 1947 1948 crypto_shash_update(shash, p, l); 1949 kunmap_atomic(mapped_buffer); 1950 len -= l; 1951 if (len == 0) 1952 break; 1953 index++; 1954 BUG_ON(index >= sblock->page_count); 1955 BUG_ON(!sblock->pagev[index]->page); 1956 page = sblock->pagev[index]->page; 1957 mapped_buffer = kmap_atomic(page); 1958 mapped_size = PAGE_SIZE; 1959 p = mapped_buffer; 1960 } 1961 1962 crypto_shash_final(shash, calculated_csum); 1963 if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size)) 1964 ++fail_cor; 1965 1966 if (fail_cor + fail_gen) { 1967 /* 1968 * if we find an error in a super block, we just report it. 1969 * They will get written with the next transaction commit 1970 * anyway 1971 */ 1972 spin_lock(&sctx->stat_lock); 1973 ++sctx->stat.super_errors; 1974 spin_unlock(&sctx->stat_lock); 1975 if (fail_cor) 1976 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev, 1977 BTRFS_DEV_STAT_CORRUPTION_ERRS); 1978 else 1979 btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev, 1980 BTRFS_DEV_STAT_GENERATION_ERRS); 1981 } 1982 1983 return fail_cor + fail_gen; 1984 } 1985 1986 static void scrub_block_get(struct scrub_block *sblock) 1987 { 1988 refcount_inc(&sblock->refs); 1989 } 1990 1991 static void scrub_block_put(struct scrub_block *sblock) 1992 { 1993 if (refcount_dec_and_test(&sblock->refs)) { 1994 int i; 1995 1996 if (sblock->sparity) 1997 scrub_parity_put(sblock->sparity); 1998 1999 for (i = 0; i < sblock->page_count; i++) 2000 scrub_page_put(sblock->pagev[i]); 2001 kfree(sblock); 2002 } 2003 } 2004 2005 static void scrub_page_get(struct scrub_page *spage) 2006 { 2007 atomic_inc(&spage->refs); 2008 } 2009 2010 static void scrub_page_put(struct scrub_page *spage) 2011 { 2012 if (atomic_dec_and_test(&spage->refs)) { 2013 if (spage->page) 2014 __free_page(spage->page); 2015 kfree(spage); 2016 } 2017 } 2018 2019 static void scrub_submit(struct scrub_ctx *sctx) 2020 { 2021 struct scrub_bio *sbio; 2022 2023 if (sctx->curr == -1) 2024 return; 2025 2026 sbio = sctx->bios[sctx->curr]; 2027 sctx->curr = -1; 2028 scrub_pending_bio_inc(sctx); 2029 btrfsic_submit_bio(sbio->bio); 2030 } 2031 2032 static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx, 2033 struct scrub_page *spage) 2034 { 2035 struct scrub_block *sblock = spage->sblock; 2036 struct scrub_bio *sbio; 2037 int ret; 2038 2039 again: 2040 /* 2041 * grab a fresh bio or wait for one to become available 2042 */ 2043 while (sctx->curr == -1) { 2044 spin_lock(&sctx->list_lock); 2045 sctx->curr = sctx->first_free; 2046 if (sctx->curr != -1) { 2047 sctx->first_free = sctx->bios[sctx->curr]->next_free; 2048 sctx->bios[sctx->curr]->next_free = -1; 2049 sctx->bios[sctx->curr]->page_count = 0; 2050 spin_unlock(&sctx->list_lock); 2051 } else { 2052 spin_unlock(&sctx->list_lock); 2053 wait_event(sctx->list_wait, sctx->first_free != -1); 2054 } 2055 } 2056 sbio = sctx->bios[sctx->curr]; 2057 if (sbio->page_count == 0) { 2058 struct bio *bio; 2059 2060 sbio->physical = spage->physical; 2061 sbio->logical = spage->logical; 2062 sbio->dev = spage->dev; 2063 bio = sbio->bio; 2064 if (!bio) { 2065 bio = btrfs_io_bio_alloc(sctx->pages_per_rd_bio); 2066 sbio->bio = bio; 2067 } 2068 2069 bio->bi_private = sbio; 2070 bio->bi_end_io = scrub_bio_end_io; 2071 bio_set_dev(bio, sbio->dev->bdev); 2072 bio->bi_iter.bi_sector = sbio->physical >> 9; 2073 bio->bi_opf = REQ_OP_READ; 2074 sbio->status = 0; 2075 } else if (sbio->physical + sbio->page_count * PAGE_SIZE != 2076 spage->physical || 2077 sbio->logical + sbio->page_count * PAGE_SIZE != 2078 spage->logical || 2079 sbio->dev != spage->dev) { 2080 scrub_submit(sctx); 2081 goto again; 2082 } 2083 2084 sbio->pagev[sbio->page_count] = spage; 2085 ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0); 2086 if (ret != PAGE_SIZE) { 2087 if (sbio->page_count < 1) { 2088 bio_put(sbio->bio); 2089 sbio->bio = NULL; 2090 return -EIO; 2091 } 2092 scrub_submit(sctx); 2093 goto again; 2094 } 2095 2096 scrub_block_get(sblock); /* one for the page added to the bio */ 2097 atomic_inc(&sblock->outstanding_pages); 2098 sbio->page_count++; 2099 if (sbio->page_count == sctx->pages_per_rd_bio) 2100 scrub_submit(sctx); 2101 2102 return 0; 2103 } 2104 2105 static void scrub_missing_raid56_end_io(struct bio *bio) 2106 { 2107 struct scrub_block *sblock = bio->bi_private; 2108 struct btrfs_fs_info *fs_info = sblock->sctx->fs_info; 2109 2110 if (bio->bi_status) 2111 sblock->no_io_error_seen = 0; 2112 2113 bio_put(bio); 2114 2115 btrfs_queue_work(fs_info->scrub_workers, &sblock->work); 2116 } 2117 2118 static void scrub_missing_raid56_worker(struct btrfs_work *work) 2119 { 2120 struct scrub_block *sblock = container_of(work, struct scrub_block, work); 2121 struct scrub_ctx *sctx = sblock->sctx; 2122 struct btrfs_fs_info *fs_info = sctx->fs_info; 2123 u64 logical; 2124 struct btrfs_device *dev; 2125 2126 logical = sblock->pagev[0]->logical; 2127 dev = sblock->pagev[0]->dev; 2128 2129 if (sblock->no_io_error_seen) 2130 scrub_recheck_block_checksum(sblock); 2131 2132 if (!sblock->no_io_error_seen) { 2133 spin_lock(&sctx->stat_lock); 2134 sctx->stat.read_errors++; 2135 spin_unlock(&sctx->stat_lock); 2136 btrfs_err_rl_in_rcu(fs_info, 2137 "IO error rebuilding logical %llu for dev %s", 2138 logical, rcu_str_deref(dev->name)); 2139 } else if (sblock->header_error || sblock->checksum_error) { 2140 spin_lock(&sctx->stat_lock); 2141 sctx->stat.uncorrectable_errors++; 2142 spin_unlock(&sctx->stat_lock); 2143 btrfs_err_rl_in_rcu(fs_info, 2144 "failed to rebuild valid logical %llu for dev %s", 2145 logical, rcu_str_deref(dev->name)); 2146 } else { 2147 scrub_write_block_to_dev_replace(sblock); 2148 } 2149 2150 if (sctx->is_dev_replace && sctx->flush_all_writes) { 2151 mutex_lock(&sctx->wr_lock); 2152 scrub_wr_submit(sctx); 2153 mutex_unlock(&sctx->wr_lock); 2154 } 2155 2156 scrub_block_put(sblock); 2157 scrub_pending_bio_dec(sctx); 2158 } 2159 2160 static void scrub_missing_raid56_pages(struct scrub_block *sblock) 2161 { 2162 struct scrub_ctx *sctx = sblock->sctx; 2163 struct btrfs_fs_info *fs_info = sctx->fs_info; 2164 u64 length = sblock->page_count * PAGE_SIZE; 2165 u64 logical = sblock->pagev[0]->logical; 2166 struct btrfs_bio *bbio = NULL; 2167 struct bio *bio; 2168 struct btrfs_raid_bio *rbio; 2169 int ret; 2170 int i; 2171 2172 btrfs_bio_counter_inc_blocked(fs_info); 2173 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical, 2174 &length, &bbio); 2175 if (ret || !bbio || !bbio->raid_map) 2176 goto bbio_out; 2177 2178 if (WARN_ON(!sctx->is_dev_replace || 2179 !(bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK))) { 2180 /* 2181 * We shouldn't be scrubbing a missing device. Even for dev 2182 * replace, we should only get here for RAID 5/6. We either 2183 * managed to mount something with no mirrors remaining or 2184 * there's a bug in scrub_remap_extent()/btrfs_map_block(). 2185 */ 2186 goto bbio_out; 2187 } 2188 2189 bio = btrfs_io_bio_alloc(0); 2190 bio->bi_iter.bi_sector = logical >> 9; 2191 bio->bi_private = sblock; 2192 bio->bi_end_io = scrub_missing_raid56_end_io; 2193 2194 rbio = raid56_alloc_missing_rbio(fs_info, bio, bbio, length); 2195 if (!rbio) 2196 goto rbio_out; 2197 2198 for (i = 0; i < sblock->page_count; i++) { 2199 struct scrub_page *spage = sblock->pagev[i]; 2200 2201 raid56_add_scrub_pages(rbio, spage->page, spage->logical); 2202 } 2203 2204 btrfs_init_work(&sblock->work, scrub_missing_raid56_worker, NULL, NULL); 2205 scrub_block_get(sblock); 2206 scrub_pending_bio_inc(sctx); 2207 raid56_submit_missing_rbio(rbio); 2208 return; 2209 2210 rbio_out: 2211 bio_put(bio); 2212 bbio_out: 2213 btrfs_bio_counter_dec(fs_info); 2214 btrfs_put_bbio(bbio); 2215 spin_lock(&sctx->stat_lock); 2216 sctx->stat.malloc_errors++; 2217 spin_unlock(&sctx->stat_lock); 2218 } 2219 2220 static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len, 2221 u64 physical, struct btrfs_device *dev, u64 flags, 2222 u64 gen, int mirror_num, u8 *csum, int force, 2223 u64 physical_for_dev_replace) 2224 { 2225 struct scrub_block *sblock; 2226 int index; 2227 2228 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL); 2229 if (!sblock) { 2230 spin_lock(&sctx->stat_lock); 2231 sctx->stat.malloc_errors++; 2232 spin_unlock(&sctx->stat_lock); 2233 return -ENOMEM; 2234 } 2235 2236 /* one ref inside this function, plus one for each page added to 2237 * a bio later on */ 2238 refcount_set(&sblock->refs, 1); 2239 sblock->sctx = sctx; 2240 sblock->no_io_error_seen = 1; 2241 2242 for (index = 0; len > 0; index++) { 2243 struct scrub_page *spage; 2244 u64 l = min_t(u64, len, PAGE_SIZE); 2245 2246 spage = kzalloc(sizeof(*spage), GFP_KERNEL); 2247 if (!spage) { 2248 leave_nomem: 2249 spin_lock(&sctx->stat_lock); 2250 sctx->stat.malloc_errors++; 2251 spin_unlock(&sctx->stat_lock); 2252 scrub_block_put(sblock); 2253 return -ENOMEM; 2254 } 2255 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK); 2256 scrub_page_get(spage); 2257 sblock->pagev[index] = spage; 2258 spage->sblock = sblock; 2259 spage->dev = dev; 2260 spage->flags = flags; 2261 spage->generation = gen; 2262 spage->logical = logical; 2263 spage->physical = physical; 2264 spage->physical_for_dev_replace = physical_for_dev_replace; 2265 spage->mirror_num = mirror_num; 2266 if (csum) { 2267 spage->have_csum = 1; 2268 memcpy(spage->csum, csum, sctx->csum_size); 2269 } else { 2270 spage->have_csum = 0; 2271 } 2272 sblock->page_count++; 2273 spage->page = alloc_page(GFP_KERNEL); 2274 if (!spage->page) 2275 goto leave_nomem; 2276 len -= l; 2277 logical += l; 2278 physical += l; 2279 physical_for_dev_replace += l; 2280 } 2281 2282 WARN_ON(sblock->page_count == 0); 2283 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) { 2284 /* 2285 * This case should only be hit for RAID 5/6 device replace. See 2286 * the comment in scrub_missing_raid56_pages() for details. 2287 */ 2288 scrub_missing_raid56_pages(sblock); 2289 } else { 2290 for (index = 0; index < sblock->page_count; index++) { 2291 struct scrub_page *spage = sblock->pagev[index]; 2292 int ret; 2293 2294 ret = scrub_add_page_to_rd_bio(sctx, spage); 2295 if (ret) { 2296 scrub_block_put(sblock); 2297 return ret; 2298 } 2299 } 2300 2301 if (force) 2302 scrub_submit(sctx); 2303 } 2304 2305 /* last one frees, either here or in bio completion for last page */ 2306 scrub_block_put(sblock); 2307 return 0; 2308 } 2309 2310 static void scrub_bio_end_io(struct bio *bio) 2311 { 2312 struct scrub_bio *sbio = bio->bi_private; 2313 struct btrfs_fs_info *fs_info = sbio->dev->fs_info; 2314 2315 sbio->status = bio->bi_status; 2316 sbio->bio = bio; 2317 2318 btrfs_queue_work(fs_info->scrub_workers, &sbio->work); 2319 } 2320 2321 static void scrub_bio_end_io_worker(struct btrfs_work *work) 2322 { 2323 struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); 2324 struct scrub_ctx *sctx = sbio->sctx; 2325 int i; 2326 2327 BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO); 2328 if (sbio->status) { 2329 for (i = 0; i < sbio->page_count; i++) { 2330 struct scrub_page *spage = sbio->pagev[i]; 2331 2332 spage->io_error = 1; 2333 spage->sblock->no_io_error_seen = 0; 2334 } 2335 } 2336 2337 /* now complete the scrub_block items that have all pages completed */ 2338 for (i = 0; i < sbio->page_count; i++) { 2339 struct scrub_page *spage = sbio->pagev[i]; 2340 struct scrub_block *sblock = spage->sblock; 2341 2342 if (atomic_dec_and_test(&sblock->outstanding_pages)) 2343 scrub_block_complete(sblock); 2344 scrub_block_put(sblock); 2345 } 2346 2347 bio_put(sbio->bio); 2348 sbio->bio = NULL; 2349 spin_lock(&sctx->list_lock); 2350 sbio->next_free = sctx->first_free; 2351 sctx->first_free = sbio->index; 2352 spin_unlock(&sctx->list_lock); 2353 2354 if (sctx->is_dev_replace && sctx->flush_all_writes) { 2355 mutex_lock(&sctx->wr_lock); 2356 scrub_wr_submit(sctx); 2357 mutex_unlock(&sctx->wr_lock); 2358 } 2359 2360 scrub_pending_bio_dec(sctx); 2361 } 2362 2363 static inline void __scrub_mark_bitmap(struct scrub_parity *sparity, 2364 unsigned long *bitmap, 2365 u64 start, u64 len) 2366 { 2367 u64 offset; 2368 u64 nsectors64; 2369 u32 nsectors; 2370 int sectorsize = sparity->sctx->fs_info->sectorsize; 2371 2372 if (len >= sparity->stripe_len) { 2373 bitmap_set(bitmap, 0, sparity->nsectors); 2374 return; 2375 } 2376 2377 start -= sparity->logic_start; 2378 start = div64_u64_rem(start, sparity->stripe_len, &offset); 2379 offset = div_u64(offset, sectorsize); 2380 nsectors64 = div_u64(len, sectorsize); 2381 2382 ASSERT(nsectors64 < UINT_MAX); 2383 nsectors = (u32)nsectors64; 2384 2385 if (offset + nsectors <= sparity->nsectors) { 2386 bitmap_set(bitmap, offset, nsectors); 2387 return; 2388 } 2389 2390 bitmap_set(bitmap, offset, sparity->nsectors - offset); 2391 bitmap_set(bitmap, 0, nsectors - (sparity->nsectors - offset)); 2392 } 2393 2394 static inline void scrub_parity_mark_sectors_error(struct scrub_parity *sparity, 2395 u64 start, u64 len) 2396 { 2397 __scrub_mark_bitmap(sparity, sparity->ebitmap, start, len); 2398 } 2399 2400 static inline void scrub_parity_mark_sectors_data(struct scrub_parity *sparity, 2401 u64 start, u64 len) 2402 { 2403 __scrub_mark_bitmap(sparity, sparity->dbitmap, start, len); 2404 } 2405 2406 static void scrub_block_complete(struct scrub_block *sblock) 2407 { 2408 int corrupted = 0; 2409 2410 if (!sblock->no_io_error_seen) { 2411 corrupted = 1; 2412 scrub_handle_errored_block(sblock); 2413 } else { 2414 /* 2415 * if has checksum error, write via repair mechanism in 2416 * dev replace case, otherwise write here in dev replace 2417 * case. 2418 */ 2419 corrupted = scrub_checksum(sblock); 2420 if (!corrupted && sblock->sctx->is_dev_replace) 2421 scrub_write_block_to_dev_replace(sblock); 2422 } 2423 2424 if (sblock->sparity && corrupted && !sblock->data_corrected) { 2425 u64 start = sblock->pagev[0]->logical; 2426 u64 end = sblock->pagev[sblock->page_count - 1]->logical + 2427 PAGE_SIZE; 2428 2429 scrub_parity_mark_sectors_error(sblock->sparity, 2430 start, end - start); 2431 } 2432 } 2433 2434 static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum) 2435 { 2436 struct btrfs_ordered_sum *sum = NULL; 2437 unsigned long index; 2438 unsigned long num_sectors; 2439 2440 while (!list_empty(&sctx->csum_list)) { 2441 sum = list_first_entry(&sctx->csum_list, 2442 struct btrfs_ordered_sum, list); 2443 if (sum->bytenr > logical) 2444 return 0; 2445 if (sum->bytenr + sum->len > logical) 2446 break; 2447 2448 ++sctx->stat.csum_discards; 2449 list_del(&sum->list); 2450 kfree(sum); 2451 sum = NULL; 2452 } 2453 if (!sum) 2454 return 0; 2455 2456 index = div_u64(logical - sum->bytenr, sctx->fs_info->sectorsize); 2457 ASSERT(index < UINT_MAX); 2458 2459 num_sectors = sum->len / sctx->fs_info->sectorsize; 2460 memcpy(csum, sum->sums + index * sctx->csum_size, sctx->csum_size); 2461 if (index == num_sectors - 1) { 2462 list_del(&sum->list); 2463 kfree(sum); 2464 } 2465 return 1; 2466 } 2467 2468 /* scrub extent tries to collect up to 64 kB for each bio */ 2469 static int scrub_extent(struct scrub_ctx *sctx, struct map_lookup *map, 2470 u64 logical, u64 len, 2471 u64 physical, struct btrfs_device *dev, u64 flags, 2472 u64 gen, int mirror_num, u64 physical_for_dev_replace) 2473 { 2474 int ret; 2475 u8 csum[BTRFS_CSUM_SIZE]; 2476 u32 blocksize; 2477 2478 if (flags & BTRFS_EXTENT_FLAG_DATA) { 2479 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) 2480 blocksize = map->stripe_len; 2481 else 2482 blocksize = sctx->fs_info->sectorsize; 2483 spin_lock(&sctx->stat_lock); 2484 sctx->stat.data_extents_scrubbed++; 2485 sctx->stat.data_bytes_scrubbed += len; 2486 spin_unlock(&sctx->stat_lock); 2487 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 2488 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) 2489 blocksize = map->stripe_len; 2490 else 2491 blocksize = sctx->fs_info->nodesize; 2492 spin_lock(&sctx->stat_lock); 2493 sctx->stat.tree_extents_scrubbed++; 2494 sctx->stat.tree_bytes_scrubbed += len; 2495 spin_unlock(&sctx->stat_lock); 2496 } else { 2497 blocksize = sctx->fs_info->sectorsize; 2498 WARN_ON(1); 2499 } 2500 2501 while (len) { 2502 u64 l = min_t(u64, len, blocksize); 2503 int have_csum = 0; 2504 2505 if (flags & BTRFS_EXTENT_FLAG_DATA) { 2506 /* push csums to sbio */ 2507 have_csum = scrub_find_csum(sctx, logical, csum); 2508 if (have_csum == 0) 2509 ++sctx->stat.no_csum; 2510 } 2511 ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen, 2512 mirror_num, have_csum ? csum : NULL, 0, 2513 physical_for_dev_replace); 2514 if (ret) 2515 return ret; 2516 len -= l; 2517 logical += l; 2518 physical += l; 2519 physical_for_dev_replace += l; 2520 } 2521 return 0; 2522 } 2523 2524 static int scrub_pages_for_parity(struct scrub_parity *sparity, 2525 u64 logical, u64 len, 2526 u64 physical, struct btrfs_device *dev, 2527 u64 flags, u64 gen, int mirror_num, u8 *csum) 2528 { 2529 struct scrub_ctx *sctx = sparity->sctx; 2530 struct scrub_block *sblock; 2531 int index; 2532 2533 sblock = kzalloc(sizeof(*sblock), GFP_KERNEL); 2534 if (!sblock) { 2535 spin_lock(&sctx->stat_lock); 2536 sctx->stat.malloc_errors++; 2537 spin_unlock(&sctx->stat_lock); 2538 return -ENOMEM; 2539 } 2540 2541 /* one ref inside this function, plus one for each page added to 2542 * a bio later on */ 2543 refcount_set(&sblock->refs, 1); 2544 sblock->sctx = sctx; 2545 sblock->no_io_error_seen = 1; 2546 sblock->sparity = sparity; 2547 scrub_parity_get(sparity); 2548 2549 for (index = 0; len > 0; index++) { 2550 struct scrub_page *spage; 2551 u64 l = min_t(u64, len, PAGE_SIZE); 2552 2553 spage = kzalloc(sizeof(*spage), GFP_KERNEL); 2554 if (!spage) { 2555 leave_nomem: 2556 spin_lock(&sctx->stat_lock); 2557 sctx->stat.malloc_errors++; 2558 spin_unlock(&sctx->stat_lock); 2559 scrub_block_put(sblock); 2560 return -ENOMEM; 2561 } 2562 BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK); 2563 /* For scrub block */ 2564 scrub_page_get(spage); 2565 sblock->pagev[index] = spage; 2566 /* For scrub parity */ 2567 scrub_page_get(spage); 2568 list_add_tail(&spage->list, &sparity->spages); 2569 spage->sblock = sblock; 2570 spage->dev = dev; 2571 spage->flags = flags; 2572 spage->generation = gen; 2573 spage->logical = logical; 2574 spage->physical = physical; 2575 spage->mirror_num = mirror_num; 2576 if (csum) { 2577 spage->have_csum = 1; 2578 memcpy(spage->csum, csum, sctx->csum_size); 2579 } else { 2580 spage->have_csum = 0; 2581 } 2582 sblock->page_count++; 2583 spage->page = alloc_page(GFP_KERNEL); 2584 if (!spage->page) 2585 goto leave_nomem; 2586 len -= l; 2587 logical += l; 2588 physical += l; 2589 } 2590 2591 WARN_ON(sblock->page_count == 0); 2592 for (index = 0; index < sblock->page_count; index++) { 2593 struct scrub_page *spage = sblock->pagev[index]; 2594 int ret; 2595 2596 ret = scrub_add_page_to_rd_bio(sctx, spage); 2597 if (ret) { 2598 scrub_block_put(sblock); 2599 return ret; 2600 } 2601 } 2602 2603 /* last one frees, either here or in bio completion for last page */ 2604 scrub_block_put(sblock); 2605 return 0; 2606 } 2607 2608 static int scrub_extent_for_parity(struct scrub_parity *sparity, 2609 u64 logical, u64 len, 2610 u64 physical, struct btrfs_device *dev, 2611 u64 flags, u64 gen, int mirror_num) 2612 { 2613 struct scrub_ctx *sctx = sparity->sctx; 2614 int ret; 2615 u8 csum[BTRFS_CSUM_SIZE]; 2616 u32 blocksize; 2617 2618 if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) { 2619 scrub_parity_mark_sectors_error(sparity, logical, len); 2620 return 0; 2621 } 2622 2623 if (flags & BTRFS_EXTENT_FLAG_DATA) { 2624 blocksize = sparity->stripe_len; 2625 } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { 2626 blocksize = sparity->stripe_len; 2627 } else { 2628 blocksize = sctx->fs_info->sectorsize; 2629 WARN_ON(1); 2630 } 2631 2632 while (len) { 2633 u64 l = min_t(u64, len, blocksize); 2634 int have_csum = 0; 2635 2636 if (flags & BTRFS_EXTENT_FLAG_DATA) { 2637 /* push csums to sbio */ 2638 have_csum = scrub_find_csum(sctx, logical, csum); 2639 if (have_csum == 0) 2640 goto skip; 2641 } 2642 ret = scrub_pages_for_parity(sparity, logical, l, physical, dev, 2643 flags, gen, mirror_num, 2644 have_csum ? csum : NULL); 2645 if (ret) 2646 return ret; 2647 skip: 2648 len -= l; 2649 logical += l; 2650 physical += l; 2651 } 2652 return 0; 2653 } 2654 2655 /* 2656 * Given a physical address, this will calculate it's 2657 * logical offset. if this is a parity stripe, it will return 2658 * the most left data stripe's logical offset. 2659 * 2660 * return 0 if it is a data stripe, 1 means parity stripe. 2661 */ 2662 static int get_raid56_logic_offset(u64 physical, int num, 2663 struct map_lookup *map, u64 *offset, 2664 u64 *stripe_start) 2665 { 2666 int i; 2667 int j = 0; 2668 u64 stripe_nr; 2669 u64 last_offset; 2670 u32 stripe_index; 2671 u32 rot; 2672 const int data_stripes = nr_data_stripes(map); 2673 2674 last_offset = (physical - map->stripes[num].physical) * data_stripes; 2675 if (stripe_start) 2676 *stripe_start = last_offset; 2677 2678 *offset = last_offset; 2679 for (i = 0; i < data_stripes; i++) { 2680 *offset = last_offset + i * map->stripe_len; 2681 2682 stripe_nr = div64_u64(*offset, map->stripe_len); 2683 stripe_nr = div_u64(stripe_nr, data_stripes); 2684 2685 /* Work out the disk rotation on this stripe-set */ 2686 stripe_nr = div_u64_rem(stripe_nr, map->num_stripes, &rot); 2687 /* calculate which stripe this data locates */ 2688 rot += i; 2689 stripe_index = rot % map->num_stripes; 2690 if (stripe_index == num) 2691 return 0; 2692 if (stripe_index < num) 2693 j++; 2694 } 2695 *offset = last_offset + j * map->stripe_len; 2696 return 1; 2697 } 2698 2699 static void scrub_free_parity(struct scrub_parity *sparity) 2700 { 2701 struct scrub_ctx *sctx = sparity->sctx; 2702 struct scrub_page *curr, *next; 2703 int nbits; 2704 2705 nbits = bitmap_weight(sparity->ebitmap, sparity->nsectors); 2706 if (nbits) { 2707 spin_lock(&sctx->stat_lock); 2708 sctx->stat.read_errors += nbits; 2709 sctx->stat.uncorrectable_errors += nbits; 2710 spin_unlock(&sctx->stat_lock); 2711 } 2712 2713 list_for_each_entry_safe(curr, next, &sparity->spages, list) { 2714 list_del_init(&curr->list); 2715 scrub_page_put(curr); 2716 } 2717 2718 kfree(sparity); 2719 } 2720 2721 static void scrub_parity_bio_endio_worker(struct btrfs_work *work) 2722 { 2723 struct scrub_parity *sparity = container_of(work, struct scrub_parity, 2724 work); 2725 struct scrub_ctx *sctx = sparity->sctx; 2726 2727 scrub_free_parity(sparity); 2728 scrub_pending_bio_dec(sctx); 2729 } 2730 2731 static void scrub_parity_bio_endio(struct bio *bio) 2732 { 2733 struct scrub_parity *sparity = (struct scrub_parity *)bio->bi_private; 2734 struct btrfs_fs_info *fs_info = sparity->sctx->fs_info; 2735 2736 if (bio->bi_status) 2737 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap, 2738 sparity->nsectors); 2739 2740 bio_put(bio); 2741 2742 btrfs_init_work(&sparity->work, scrub_parity_bio_endio_worker, NULL, 2743 NULL); 2744 btrfs_queue_work(fs_info->scrub_parity_workers, &sparity->work); 2745 } 2746 2747 static void scrub_parity_check_and_repair(struct scrub_parity *sparity) 2748 { 2749 struct scrub_ctx *sctx = sparity->sctx; 2750 struct btrfs_fs_info *fs_info = sctx->fs_info; 2751 struct bio *bio; 2752 struct btrfs_raid_bio *rbio; 2753 struct btrfs_bio *bbio = NULL; 2754 u64 length; 2755 int ret; 2756 2757 if (!bitmap_andnot(sparity->dbitmap, sparity->dbitmap, sparity->ebitmap, 2758 sparity->nsectors)) 2759 goto out; 2760 2761 length = sparity->logic_end - sparity->logic_start; 2762 2763 btrfs_bio_counter_inc_blocked(fs_info); 2764 ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start, 2765 &length, &bbio); 2766 if (ret || !bbio || !bbio->raid_map) 2767 goto bbio_out; 2768 2769 bio = btrfs_io_bio_alloc(0); 2770 bio->bi_iter.bi_sector = sparity->logic_start >> 9; 2771 bio->bi_private = sparity; 2772 bio->bi_end_io = scrub_parity_bio_endio; 2773 2774 rbio = raid56_parity_alloc_scrub_rbio(fs_info, bio, bbio, 2775 length, sparity->scrub_dev, 2776 sparity->dbitmap, 2777 sparity->nsectors); 2778 if (!rbio) 2779 goto rbio_out; 2780 2781 scrub_pending_bio_inc(sctx); 2782 raid56_parity_submit_scrub_rbio(rbio); 2783 return; 2784 2785 rbio_out: 2786 bio_put(bio); 2787 bbio_out: 2788 btrfs_bio_counter_dec(fs_info); 2789 btrfs_put_bbio(bbio); 2790 bitmap_or(sparity->ebitmap, sparity->ebitmap, sparity->dbitmap, 2791 sparity->nsectors); 2792 spin_lock(&sctx->stat_lock); 2793 sctx->stat.malloc_errors++; 2794 spin_unlock(&sctx->stat_lock); 2795 out: 2796 scrub_free_parity(sparity); 2797 } 2798 2799 static inline int scrub_calc_parity_bitmap_len(int nsectors) 2800 { 2801 return DIV_ROUND_UP(nsectors, BITS_PER_LONG) * sizeof(long); 2802 } 2803 2804 static void scrub_parity_get(struct scrub_parity *sparity) 2805 { 2806 refcount_inc(&sparity->refs); 2807 } 2808 2809 static void scrub_parity_put(struct scrub_parity *sparity) 2810 { 2811 if (!refcount_dec_and_test(&sparity->refs)) 2812 return; 2813 2814 scrub_parity_check_and_repair(sparity); 2815 } 2816 2817 static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx, 2818 struct map_lookup *map, 2819 struct btrfs_device *sdev, 2820 struct btrfs_path *path, 2821 u64 logic_start, 2822 u64 logic_end) 2823 { 2824 struct btrfs_fs_info *fs_info = sctx->fs_info; 2825 struct btrfs_root *root = fs_info->extent_root; 2826 struct btrfs_root *csum_root = fs_info->csum_root; 2827 struct btrfs_extent_item *extent; 2828 struct btrfs_bio *bbio = NULL; 2829 u64 flags; 2830 int ret; 2831 int slot; 2832 struct extent_buffer *l; 2833 struct btrfs_key key; 2834 u64 generation; 2835 u64 extent_logical; 2836 u64 extent_physical; 2837 u64 extent_len; 2838 u64 mapped_length; 2839 struct btrfs_device *extent_dev; 2840 struct scrub_parity *sparity; 2841 int nsectors; 2842 int bitmap_len; 2843 int extent_mirror_num; 2844 int stop_loop = 0; 2845 2846 nsectors = div_u64(map->stripe_len, fs_info->sectorsize); 2847 bitmap_len = scrub_calc_parity_bitmap_len(nsectors); 2848 sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len, 2849 GFP_NOFS); 2850 if (!sparity) { 2851 spin_lock(&sctx->stat_lock); 2852 sctx->stat.malloc_errors++; 2853 spin_unlock(&sctx->stat_lock); 2854 return -ENOMEM; 2855 } 2856 2857 sparity->stripe_len = map->stripe_len; 2858 sparity->nsectors = nsectors; 2859 sparity->sctx = sctx; 2860 sparity->scrub_dev = sdev; 2861 sparity->logic_start = logic_start; 2862 sparity->logic_end = logic_end; 2863 refcount_set(&sparity->refs, 1); 2864 INIT_LIST_HEAD(&sparity->spages); 2865 sparity->dbitmap = sparity->bitmap; 2866 sparity->ebitmap = (void *)sparity->bitmap + bitmap_len; 2867 2868 ret = 0; 2869 while (logic_start < logic_end) { 2870 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) 2871 key.type = BTRFS_METADATA_ITEM_KEY; 2872 else 2873 key.type = BTRFS_EXTENT_ITEM_KEY; 2874 key.objectid = logic_start; 2875 key.offset = (u64)-1; 2876 2877 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 2878 if (ret < 0) 2879 goto out; 2880 2881 if (ret > 0) { 2882 ret = btrfs_previous_extent_item(root, path, 0); 2883 if (ret < 0) 2884 goto out; 2885 if (ret > 0) { 2886 btrfs_release_path(path); 2887 ret = btrfs_search_slot(NULL, root, &key, 2888 path, 0, 0); 2889 if (ret < 0) 2890 goto out; 2891 } 2892 } 2893 2894 stop_loop = 0; 2895 while (1) { 2896 u64 bytes; 2897 2898 l = path->nodes[0]; 2899 slot = path->slots[0]; 2900 if (slot >= btrfs_header_nritems(l)) { 2901 ret = btrfs_next_leaf(root, path); 2902 if (ret == 0) 2903 continue; 2904 if (ret < 0) 2905 goto out; 2906 2907 stop_loop = 1; 2908 break; 2909 } 2910 btrfs_item_key_to_cpu(l, &key, slot); 2911 2912 if (key.type != BTRFS_EXTENT_ITEM_KEY && 2913 key.type != BTRFS_METADATA_ITEM_KEY) 2914 goto next; 2915 2916 if (key.type == BTRFS_METADATA_ITEM_KEY) 2917 bytes = fs_info->nodesize; 2918 else 2919 bytes = key.offset; 2920 2921 if (key.objectid + bytes <= logic_start) 2922 goto next; 2923 2924 if (key.objectid >= logic_end) { 2925 stop_loop = 1; 2926 break; 2927 } 2928 2929 while (key.objectid >= logic_start + map->stripe_len) 2930 logic_start += map->stripe_len; 2931 2932 extent = btrfs_item_ptr(l, slot, 2933 struct btrfs_extent_item); 2934 flags = btrfs_extent_flags(l, extent); 2935 generation = btrfs_extent_generation(l, extent); 2936 2937 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) && 2938 (key.objectid < logic_start || 2939 key.objectid + bytes > 2940 logic_start + map->stripe_len)) { 2941 btrfs_err(fs_info, 2942 "scrub: tree block %llu spanning stripes, ignored. logical=%llu", 2943 key.objectid, logic_start); 2944 spin_lock(&sctx->stat_lock); 2945 sctx->stat.uncorrectable_errors++; 2946 spin_unlock(&sctx->stat_lock); 2947 goto next; 2948 } 2949 again: 2950 extent_logical = key.objectid; 2951 extent_len = bytes; 2952 2953 if (extent_logical < logic_start) { 2954 extent_len -= logic_start - extent_logical; 2955 extent_logical = logic_start; 2956 } 2957 2958 if (extent_logical + extent_len > 2959 logic_start + map->stripe_len) 2960 extent_len = logic_start + map->stripe_len - 2961 extent_logical; 2962 2963 scrub_parity_mark_sectors_data(sparity, extent_logical, 2964 extent_len); 2965 2966 mapped_length = extent_len; 2967 bbio = NULL; 2968 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, 2969 extent_logical, &mapped_length, &bbio, 2970 0); 2971 if (!ret) { 2972 if (!bbio || mapped_length < extent_len) 2973 ret = -EIO; 2974 } 2975 if (ret) { 2976 btrfs_put_bbio(bbio); 2977 goto out; 2978 } 2979 extent_physical = bbio->stripes[0].physical; 2980 extent_mirror_num = bbio->mirror_num; 2981 extent_dev = bbio->stripes[0].dev; 2982 btrfs_put_bbio(bbio); 2983 2984 ret = btrfs_lookup_csums_range(csum_root, 2985 extent_logical, 2986 extent_logical + extent_len - 1, 2987 &sctx->csum_list, 1); 2988 if (ret) 2989 goto out; 2990 2991 ret = scrub_extent_for_parity(sparity, extent_logical, 2992 extent_len, 2993 extent_physical, 2994 extent_dev, flags, 2995 generation, 2996 extent_mirror_num); 2997 2998 scrub_free_csums(sctx); 2999 3000 if (ret) 3001 goto out; 3002 3003 if (extent_logical + extent_len < 3004 key.objectid + bytes) { 3005 logic_start += map->stripe_len; 3006 3007 if (logic_start >= logic_end) { 3008 stop_loop = 1; 3009 break; 3010 } 3011 3012 if (logic_start < key.objectid + bytes) { 3013 cond_resched(); 3014 goto again; 3015 } 3016 } 3017 next: 3018 path->slots[0]++; 3019 } 3020 3021 btrfs_release_path(path); 3022 3023 if (stop_loop) 3024 break; 3025 3026 logic_start += map->stripe_len; 3027 } 3028 out: 3029 if (ret < 0) 3030 scrub_parity_mark_sectors_error(sparity, logic_start, 3031 logic_end - logic_start); 3032 scrub_parity_put(sparity); 3033 scrub_submit(sctx); 3034 mutex_lock(&sctx->wr_lock); 3035 scrub_wr_submit(sctx); 3036 mutex_unlock(&sctx->wr_lock); 3037 3038 btrfs_release_path(path); 3039 return ret < 0 ? ret : 0; 3040 } 3041 3042 static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, 3043 struct map_lookup *map, 3044 struct btrfs_device *scrub_dev, 3045 int num, u64 base, u64 length) 3046 { 3047 struct btrfs_path *path, *ppath; 3048 struct btrfs_fs_info *fs_info = sctx->fs_info; 3049 struct btrfs_root *root = fs_info->extent_root; 3050 struct btrfs_root *csum_root = fs_info->csum_root; 3051 struct btrfs_extent_item *extent; 3052 struct blk_plug plug; 3053 u64 flags; 3054 int ret; 3055 int slot; 3056 u64 nstripes; 3057 struct extent_buffer *l; 3058 u64 physical; 3059 u64 logical; 3060 u64 logic_end; 3061 u64 physical_end; 3062 u64 generation; 3063 int mirror_num; 3064 struct reada_control *reada1; 3065 struct reada_control *reada2; 3066 struct btrfs_key key; 3067 struct btrfs_key key_end; 3068 u64 increment = map->stripe_len; 3069 u64 offset; 3070 u64 extent_logical; 3071 u64 extent_physical; 3072 u64 extent_len; 3073 u64 stripe_logical; 3074 u64 stripe_end; 3075 struct btrfs_device *extent_dev; 3076 int extent_mirror_num; 3077 int stop_loop = 0; 3078 3079 physical = map->stripes[num].physical; 3080 offset = 0; 3081 nstripes = div64_u64(length, map->stripe_len); 3082 if (map->type & BTRFS_BLOCK_GROUP_RAID0) { 3083 offset = map->stripe_len * num; 3084 increment = map->stripe_len * map->num_stripes; 3085 mirror_num = 1; 3086 } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { 3087 int factor = map->num_stripes / map->sub_stripes; 3088 offset = map->stripe_len * (num / map->sub_stripes); 3089 increment = map->stripe_len * factor; 3090 mirror_num = num % map->sub_stripes + 1; 3091 } else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) { 3092 increment = map->stripe_len; 3093 mirror_num = num % map->num_stripes + 1; 3094 } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { 3095 increment = map->stripe_len; 3096 mirror_num = num % map->num_stripes + 1; 3097 } else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 3098 get_raid56_logic_offset(physical, num, map, &offset, NULL); 3099 increment = map->stripe_len * nr_data_stripes(map); 3100 mirror_num = 1; 3101 } else { 3102 increment = map->stripe_len; 3103 mirror_num = 1; 3104 } 3105 3106 path = btrfs_alloc_path(); 3107 if (!path) 3108 return -ENOMEM; 3109 3110 ppath = btrfs_alloc_path(); 3111 if (!ppath) { 3112 btrfs_free_path(path); 3113 return -ENOMEM; 3114 } 3115 3116 /* 3117 * work on commit root. The related disk blocks are static as 3118 * long as COW is applied. This means, it is save to rewrite 3119 * them to repair disk errors without any race conditions 3120 */ 3121 path->search_commit_root = 1; 3122 path->skip_locking = 1; 3123 3124 ppath->search_commit_root = 1; 3125 ppath->skip_locking = 1; 3126 /* 3127 * trigger the readahead for extent tree csum tree and wait for 3128 * completion. During readahead, the scrub is officially paused 3129 * to not hold off transaction commits 3130 */ 3131 logical = base + offset; 3132 physical_end = physical + nstripes * map->stripe_len; 3133 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 3134 get_raid56_logic_offset(physical_end, num, 3135 map, &logic_end, NULL); 3136 logic_end += base; 3137 } else { 3138 logic_end = logical + increment * nstripes; 3139 } 3140 wait_event(sctx->list_wait, 3141 atomic_read(&sctx->bios_in_flight) == 0); 3142 scrub_blocked_if_needed(fs_info); 3143 3144 /* FIXME it might be better to start readahead at commit root */ 3145 key.objectid = logical; 3146 key.type = BTRFS_EXTENT_ITEM_KEY; 3147 key.offset = (u64)0; 3148 key_end.objectid = logic_end; 3149 key_end.type = BTRFS_METADATA_ITEM_KEY; 3150 key_end.offset = (u64)-1; 3151 reada1 = btrfs_reada_add(root, &key, &key_end); 3152 3153 key.objectid = BTRFS_EXTENT_CSUM_OBJECTID; 3154 key.type = BTRFS_EXTENT_CSUM_KEY; 3155 key.offset = logical; 3156 key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID; 3157 key_end.type = BTRFS_EXTENT_CSUM_KEY; 3158 key_end.offset = logic_end; 3159 reada2 = btrfs_reada_add(csum_root, &key, &key_end); 3160 3161 if (!IS_ERR(reada1)) 3162 btrfs_reada_wait(reada1); 3163 if (!IS_ERR(reada2)) 3164 btrfs_reada_wait(reada2); 3165 3166 3167 /* 3168 * collect all data csums for the stripe to avoid seeking during 3169 * the scrub. This might currently (crc32) end up to be about 1MB 3170 */ 3171 blk_start_plug(&plug); 3172 3173 /* 3174 * now find all extents for each stripe and scrub them 3175 */ 3176 ret = 0; 3177 while (physical < physical_end) { 3178 /* 3179 * canceled? 3180 */ 3181 if (atomic_read(&fs_info->scrub_cancel_req) || 3182 atomic_read(&sctx->cancel_req)) { 3183 ret = -ECANCELED; 3184 goto out; 3185 } 3186 /* 3187 * check to see if we have to pause 3188 */ 3189 if (atomic_read(&fs_info->scrub_pause_req)) { 3190 /* push queued extents */ 3191 sctx->flush_all_writes = true; 3192 scrub_submit(sctx); 3193 mutex_lock(&sctx->wr_lock); 3194 scrub_wr_submit(sctx); 3195 mutex_unlock(&sctx->wr_lock); 3196 wait_event(sctx->list_wait, 3197 atomic_read(&sctx->bios_in_flight) == 0); 3198 sctx->flush_all_writes = false; 3199 scrub_blocked_if_needed(fs_info); 3200 } 3201 3202 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 3203 ret = get_raid56_logic_offset(physical, num, map, 3204 &logical, 3205 &stripe_logical); 3206 logical += base; 3207 if (ret) { 3208 /* it is parity strip */ 3209 stripe_logical += base; 3210 stripe_end = stripe_logical + increment; 3211 ret = scrub_raid56_parity(sctx, map, scrub_dev, 3212 ppath, stripe_logical, 3213 stripe_end); 3214 if (ret) 3215 goto out; 3216 goto skip; 3217 } 3218 } 3219 3220 if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) 3221 key.type = BTRFS_METADATA_ITEM_KEY; 3222 else 3223 key.type = BTRFS_EXTENT_ITEM_KEY; 3224 key.objectid = logical; 3225 key.offset = (u64)-1; 3226 3227 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3228 if (ret < 0) 3229 goto out; 3230 3231 if (ret > 0) { 3232 ret = btrfs_previous_extent_item(root, path, 0); 3233 if (ret < 0) 3234 goto out; 3235 if (ret > 0) { 3236 /* there's no smaller item, so stick with the 3237 * larger one */ 3238 btrfs_release_path(path); 3239 ret = btrfs_search_slot(NULL, root, &key, 3240 path, 0, 0); 3241 if (ret < 0) 3242 goto out; 3243 } 3244 } 3245 3246 stop_loop = 0; 3247 while (1) { 3248 u64 bytes; 3249 3250 l = path->nodes[0]; 3251 slot = path->slots[0]; 3252 if (slot >= btrfs_header_nritems(l)) { 3253 ret = btrfs_next_leaf(root, path); 3254 if (ret == 0) 3255 continue; 3256 if (ret < 0) 3257 goto out; 3258 3259 stop_loop = 1; 3260 break; 3261 } 3262 btrfs_item_key_to_cpu(l, &key, slot); 3263 3264 if (key.type != BTRFS_EXTENT_ITEM_KEY && 3265 key.type != BTRFS_METADATA_ITEM_KEY) 3266 goto next; 3267 3268 if (key.type == BTRFS_METADATA_ITEM_KEY) 3269 bytes = fs_info->nodesize; 3270 else 3271 bytes = key.offset; 3272 3273 if (key.objectid + bytes <= logical) 3274 goto next; 3275 3276 if (key.objectid >= logical + map->stripe_len) { 3277 /* out of this device extent */ 3278 if (key.objectid >= logic_end) 3279 stop_loop = 1; 3280 break; 3281 } 3282 3283 extent = btrfs_item_ptr(l, slot, 3284 struct btrfs_extent_item); 3285 flags = btrfs_extent_flags(l, extent); 3286 generation = btrfs_extent_generation(l, extent); 3287 3288 if ((flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) && 3289 (key.objectid < logical || 3290 key.objectid + bytes > 3291 logical + map->stripe_len)) { 3292 btrfs_err(fs_info, 3293 "scrub: tree block %llu spanning stripes, ignored. logical=%llu", 3294 key.objectid, logical); 3295 spin_lock(&sctx->stat_lock); 3296 sctx->stat.uncorrectable_errors++; 3297 spin_unlock(&sctx->stat_lock); 3298 goto next; 3299 } 3300 3301 again: 3302 extent_logical = key.objectid; 3303 extent_len = bytes; 3304 3305 /* 3306 * trim extent to this stripe 3307 */ 3308 if (extent_logical < logical) { 3309 extent_len -= logical - extent_logical; 3310 extent_logical = logical; 3311 } 3312 if (extent_logical + extent_len > 3313 logical + map->stripe_len) { 3314 extent_len = logical + map->stripe_len - 3315 extent_logical; 3316 } 3317 3318 extent_physical = extent_logical - logical + physical; 3319 extent_dev = scrub_dev; 3320 extent_mirror_num = mirror_num; 3321 if (sctx->is_dev_replace) 3322 scrub_remap_extent(fs_info, extent_logical, 3323 extent_len, &extent_physical, 3324 &extent_dev, 3325 &extent_mirror_num); 3326 3327 ret = btrfs_lookup_csums_range(csum_root, 3328 extent_logical, 3329 extent_logical + 3330 extent_len - 1, 3331 &sctx->csum_list, 1); 3332 if (ret) 3333 goto out; 3334 3335 ret = scrub_extent(sctx, map, extent_logical, extent_len, 3336 extent_physical, extent_dev, flags, 3337 generation, extent_mirror_num, 3338 extent_logical - logical + physical); 3339 3340 scrub_free_csums(sctx); 3341 3342 if (ret) 3343 goto out; 3344 3345 if (extent_logical + extent_len < 3346 key.objectid + bytes) { 3347 if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) { 3348 /* 3349 * loop until we find next data stripe 3350 * or we have finished all stripes. 3351 */ 3352 loop: 3353 physical += map->stripe_len; 3354 ret = get_raid56_logic_offset(physical, 3355 num, map, &logical, 3356 &stripe_logical); 3357 logical += base; 3358 3359 if (ret && physical < physical_end) { 3360 stripe_logical += base; 3361 stripe_end = stripe_logical + 3362 increment; 3363 ret = scrub_raid56_parity(sctx, 3364 map, scrub_dev, ppath, 3365 stripe_logical, 3366 stripe_end); 3367 if (ret) 3368 goto out; 3369 goto loop; 3370 } 3371 } else { 3372 physical += map->stripe_len; 3373 logical += increment; 3374 } 3375 if (logical < key.objectid + bytes) { 3376 cond_resched(); 3377 goto again; 3378 } 3379 3380 if (physical >= physical_end) { 3381 stop_loop = 1; 3382 break; 3383 } 3384 } 3385 next: 3386 path->slots[0]++; 3387 } 3388 btrfs_release_path(path); 3389 skip: 3390 logical += increment; 3391 physical += map->stripe_len; 3392 spin_lock(&sctx->stat_lock); 3393 if (stop_loop) 3394 sctx->stat.last_physical = map->stripes[num].physical + 3395 length; 3396 else 3397 sctx->stat.last_physical = physical; 3398 spin_unlock(&sctx->stat_lock); 3399 if (stop_loop) 3400 break; 3401 } 3402 out: 3403 /* push queued extents */ 3404 scrub_submit(sctx); 3405 mutex_lock(&sctx->wr_lock); 3406 scrub_wr_submit(sctx); 3407 mutex_unlock(&sctx->wr_lock); 3408 3409 blk_finish_plug(&plug); 3410 btrfs_free_path(path); 3411 btrfs_free_path(ppath); 3412 return ret < 0 ? ret : 0; 3413 } 3414 3415 static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx, 3416 struct btrfs_device *scrub_dev, 3417 u64 chunk_offset, u64 length, 3418 u64 dev_offset, 3419 struct btrfs_block_group *cache) 3420 { 3421 struct btrfs_fs_info *fs_info = sctx->fs_info; 3422 struct extent_map_tree *map_tree = &fs_info->mapping_tree; 3423 struct map_lookup *map; 3424 struct extent_map *em; 3425 int i; 3426 int ret = 0; 3427 3428 read_lock(&map_tree->lock); 3429 em = lookup_extent_mapping(map_tree, chunk_offset, 1); 3430 read_unlock(&map_tree->lock); 3431 3432 if (!em) { 3433 /* 3434 * Might have been an unused block group deleted by the cleaner 3435 * kthread or relocation. 3436 */ 3437 spin_lock(&cache->lock); 3438 if (!cache->removed) 3439 ret = -EINVAL; 3440 spin_unlock(&cache->lock); 3441 3442 return ret; 3443 } 3444 3445 map = em->map_lookup; 3446 if (em->start != chunk_offset) 3447 goto out; 3448 3449 if (em->len < length) 3450 goto out; 3451 3452 for (i = 0; i < map->num_stripes; ++i) { 3453 if (map->stripes[i].dev->bdev == scrub_dev->bdev && 3454 map->stripes[i].physical == dev_offset) { 3455 ret = scrub_stripe(sctx, map, scrub_dev, i, 3456 chunk_offset, length); 3457 if (ret) 3458 goto out; 3459 } 3460 } 3461 out: 3462 free_extent_map(em); 3463 3464 return ret; 3465 } 3466 3467 static noinline_for_stack 3468 int scrub_enumerate_chunks(struct scrub_ctx *sctx, 3469 struct btrfs_device *scrub_dev, u64 start, u64 end) 3470 { 3471 struct btrfs_dev_extent *dev_extent = NULL; 3472 struct btrfs_path *path; 3473 struct btrfs_fs_info *fs_info = sctx->fs_info; 3474 struct btrfs_root *root = fs_info->dev_root; 3475 u64 length; 3476 u64 chunk_offset; 3477 int ret = 0; 3478 int ro_set; 3479 int slot; 3480 struct extent_buffer *l; 3481 struct btrfs_key key; 3482 struct btrfs_key found_key; 3483 struct btrfs_block_group *cache; 3484 struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; 3485 3486 path = btrfs_alloc_path(); 3487 if (!path) 3488 return -ENOMEM; 3489 3490 path->reada = READA_FORWARD; 3491 path->search_commit_root = 1; 3492 path->skip_locking = 1; 3493 3494 key.objectid = scrub_dev->devid; 3495 key.offset = 0ull; 3496 key.type = BTRFS_DEV_EXTENT_KEY; 3497 3498 while (1) { 3499 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); 3500 if (ret < 0) 3501 break; 3502 if (ret > 0) { 3503 if (path->slots[0] >= 3504 btrfs_header_nritems(path->nodes[0])) { 3505 ret = btrfs_next_leaf(root, path); 3506 if (ret < 0) 3507 break; 3508 if (ret > 0) { 3509 ret = 0; 3510 break; 3511 } 3512 } else { 3513 ret = 0; 3514 } 3515 } 3516 3517 l = path->nodes[0]; 3518 slot = path->slots[0]; 3519 3520 btrfs_item_key_to_cpu(l, &found_key, slot); 3521 3522 if (found_key.objectid != scrub_dev->devid) 3523 break; 3524 3525 if (found_key.type != BTRFS_DEV_EXTENT_KEY) 3526 break; 3527 3528 if (found_key.offset >= end) 3529 break; 3530 3531 if (found_key.offset < key.offset) 3532 break; 3533 3534 dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); 3535 length = btrfs_dev_extent_length(l, dev_extent); 3536 3537 if (found_key.offset + length <= start) 3538 goto skip; 3539 3540 chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); 3541 3542 /* 3543 * get a reference on the corresponding block group to prevent 3544 * the chunk from going away while we scrub it 3545 */ 3546 cache = btrfs_lookup_block_group(fs_info, chunk_offset); 3547 3548 /* some chunks are removed but not committed to disk yet, 3549 * continue scrubbing */ 3550 if (!cache) 3551 goto skip; 3552 3553 /* 3554 * we need call btrfs_inc_block_group_ro() with scrubs_paused, 3555 * to avoid deadlock caused by: 3556 * btrfs_inc_block_group_ro() 3557 * -> btrfs_wait_for_commit() 3558 * -> btrfs_commit_transaction() 3559 * -> btrfs_scrub_pause() 3560 */ 3561 scrub_pause_on(fs_info); 3562 3563 /* 3564 * Don't do chunk preallocation for scrub. 3565 * 3566 * This is especially important for SYSTEM bgs, or we can hit 3567 * -EFBIG from btrfs_finish_chunk_alloc() like: 3568 * 1. The only SYSTEM bg is marked RO. 3569 * Since SYSTEM bg is small, that's pretty common. 3570 * 2. New SYSTEM bg will be allocated 3571 * Due to regular version will allocate new chunk. 3572 * 3. New SYSTEM bg is empty and will get cleaned up 3573 * Before cleanup really happens, it's marked RO again. 3574 * 4. Empty SYSTEM bg get scrubbed 3575 * We go back to 2. 3576 * 3577 * This can easily boost the amount of SYSTEM chunks if cleaner 3578 * thread can't be triggered fast enough, and use up all space 3579 * of btrfs_super_block::sys_chunk_array 3580 */ 3581 ret = btrfs_inc_block_group_ro(cache, false); 3582 scrub_pause_off(fs_info); 3583 3584 if (ret == 0) { 3585 ro_set = 1; 3586 } else if (ret == -ENOSPC) { 3587 /* 3588 * btrfs_inc_block_group_ro return -ENOSPC when it 3589 * failed in creating new chunk for metadata. 3590 * It is not a problem for scrub/replace, because 3591 * metadata are always cowed, and our scrub paused 3592 * commit_transactions. 3593 */ 3594 ro_set = 0; 3595 } else { 3596 btrfs_warn(fs_info, 3597 "failed setting block group ro: %d", ret); 3598 btrfs_put_block_group(cache); 3599 break; 3600 } 3601 3602 down_write(&dev_replace->rwsem); 3603 dev_replace->cursor_right = found_key.offset + length; 3604 dev_replace->cursor_left = found_key.offset; 3605 dev_replace->item_needs_writeback = 1; 3606 up_write(&dev_replace->rwsem); 3607 3608 ret = scrub_chunk(sctx, scrub_dev, chunk_offset, length, 3609 found_key.offset, cache); 3610 3611 /* 3612 * flush, submit all pending read and write bios, afterwards 3613 * wait for them. 3614 * Note that in the dev replace case, a read request causes 3615 * write requests that are submitted in the read completion 3616 * worker. Therefore in the current situation, it is required 3617 * that all write requests are flushed, so that all read and 3618 * write requests are really completed when bios_in_flight 3619 * changes to 0. 3620 */ 3621 sctx->flush_all_writes = true; 3622 scrub_submit(sctx); 3623 mutex_lock(&sctx->wr_lock); 3624 scrub_wr_submit(sctx); 3625 mutex_unlock(&sctx->wr_lock); 3626 3627 wait_event(sctx->list_wait, 3628 atomic_read(&sctx->bios_in_flight) == 0); 3629 3630 scrub_pause_on(fs_info); 3631 3632 /* 3633 * must be called before we decrease @scrub_paused. 3634 * make sure we don't block transaction commit while 3635 * we are waiting pending workers finished. 3636 */ 3637 wait_event(sctx->list_wait, 3638 atomic_read(&sctx->workers_pending) == 0); 3639 sctx->flush_all_writes = false; 3640 3641 scrub_pause_off(fs_info); 3642 3643 down_write(&dev_replace->rwsem); 3644 dev_replace->cursor_left = dev_replace->cursor_right; 3645 dev_replace->item_needs_writeback = 1; 3646 up_write(&dev_replace->rwsem); 3647 3648 if (ro_set) 3649 btrfs_dec_block_group_ro(cache); 3650 3651 /* 3652 * We might have prevented the cleaner kthread from deleting 3653 * this block group if it was already unused because we raced 3654 * and set it to RO mode first. So add it back to the unused 3655 * list, otherwise it might not ever be deleted unless a manual 3656 * balance is triggered or it becomes used and unused again. 3657 */ 3658 spin_lock(&cache->lock); 3659 if (!cache->removed && !cache->ro && cache->reserved == 0 && 3660 cache->used == 0) { 3661 spin_unlock(&cache->lock); 3662 btrfs_mark_bg_unused(cache); 3663 } else { 3664 spin_unlock(&cache->lock); 3665 } 3666 3667 btrfs_put_block_group(cache); 3668 if (ret) 3669 break; 3670 if (sctx->is_dev_replace && 3671 atomic64_read(&dev_replace->num_write_errors) > 0) { 3672 ret = -EIO; 3673 break; 3674 } 3675 if (sctx->stat.malloc_errors > 0) { 3676 ret = -ENOMEM; 3677 break; 3678 } 3679 skip: 3680 key.offset = found_key.offset + length; 3681 btrfs_release_path(path); 3682 } 3683 3684 btrfs_free_path(path); 3685 3686 return ret; 3687 } 3688 3689 static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx, 3690 struct btrfs_device *scrub_dev) 3691 { 3692 int i; 3693 u64 bytenr; 3694 u64 gen; 3695 int ret; 3696 struct btrfs_fs_info *fs_info = sctx->fs_info; 3697 3698 if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state)) 3699 return -EIO; 3700 3701 /* Seed devices of a new filesystem has their own generation. */ 3702 if (scrub_dev->fs_devices != fs_info->fs_devices) 3703 gen = scrub_dev->generation; 3704 else 3705 gen = fs_info->last_trans_committed; 3706 3707 for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { 3708 bytenr = btrfs_sb_offset(i); 3709 if (bytenr + BTRFS_SUPER_INFO_SIZE > 3710 scrub_dev->commit_total_bytes) 3711 break; 3712 3713 ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr, 3714 scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i, 3715 NULL, 1, bytenr); 3716 if (ret) 3717 return ret; 3718 } 3719 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); 3720 3721 return 0; 3722 } 3723 3724 /* 3725 * get a reference count on fs_info->scrub_workers. start worker if necessary 3726 */ 3727 static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info, 3728 int is_dev_replace) 3729 { 3730 unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND; 3731 int max_active = fs_info->thread_pool_size; 3732 3733 lockdep_assert_held(&fs_info->scrub_lock); 3734 3735 if (refcount_read(&fs_info->scrub_workers_refcnt) == 0) { 3736 ASSERT(fs_info->scrub_workers == NULL); 3737 fs_info->scrub_workers = btrfs_alloc_workqueue(fs_info, "scrub", 3738 flags, is_dev_replace ? 1 : max_active, 4); 3739 if (!fs_info->scrub_workers) 3740 goto fail_scrub_workers; 3741 3742 ASSERT(fs_info->scrub_wr_completion_workers == NULL); 3743 fs_info->scrub_wr_completion_workers = 3744 btrfs_alloc_workqueue(fs_info, "scrubwrc", flags, 3745 max_active, 2); 3746 if (!fs_info->scrub_wr_completion_workers) 3747 goto fail_scrub_wr_completion_workers; 3748 3749 ASSERT(fs_info->scrub_parity_workers == NULL); 3750 fs_info->scrub_parity_workers = 3751 btrfs_alloc_workqueue(fs_info, "scrubparity", flags, 3752 max_active, 2); 3753 if (!fs_info->scrub_parity_workers) 3754 goto fail_scrub_parity_workers; 3755 3756 refcount_set(&fs_info->scrub_workers_refcnt, 1); 3757 } else { 3758 refcount_inc(&fs_info->scrub_workers_refcnt); 3759 } 3760 return 0; 3761 3762 fail_scrub_parity_workers: 3763 btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers); 3764 fail_scrub_wr_completion_workers: 3765 btrfs_destroy_workqueue(fs_info->scrub_workers); 3766 fail_scrub_workers: 3767 return -ENOMEM; 3768 } 3769 3770 int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start, 3771 u64 end, struct btrfs_scrub_progress *progress, 3772 int readonly, int is_dev_replace) 3773 { 3774 struct scrub_ctx *sctx; 3775 int ret; 3776 struct btrfs_device *dev; 3777 unsigned int nofs_flag; 3778 struct btrfs_workqueue *scrub_workers = NULL; 3779 struct btrfs_workqueue *scrub_wr_comp = NULL; 3780 struct btrfs_workqueue *scrub_parity = NULL; 3781 3782 if (btrfs_fs_closing(fs_info)) 3783 return -EAGAIN; 3784 3785 if (fs_info->nodesize > BTRFS_STRIPE_LEN) { 3786 /* 3787 * in this case scrub is unable to calculate the checksum 3788 * the way scrub is implemented. Do not handle this 3789 * situation at all because it won't ever happen. 3790 */ 3791 btrfs_err(fs_info, 3792 "scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails", 3793 fs_info->nodesize, 3794 BTRFS_STRIPE_LEN); 3795 return -EINVAL; 3796 } 3797 3798 if (fs_info->sectorsize != PAGE_SIZE) { 3799 /* not supported for data w/o checksums */ 3800 btrfs_err_rl(fs_info, 3801 "scrub: size assumption sectorsize != PAGE_SIZE (%d != %lu) fails", 3802 fs_info->sectorsize, PAGE_SIZE); 3803 return -EINVAL; 3804 } 3805 3806 if (fs_info->nodesize > 3807 PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK || 3808 fs_info->sectorsize > PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) { 3809 /* 3810 * would exhaust the array bounds of pagev member in 3811 * struct scrub_block 3812 */ 3813 btrfs_err(fs_info, 3814 "scrub: size assumption nodesize and sectorsize <= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails", 3815 fs_info->nodesize, 3816 SCRUB_MAX_PAGES_PER_BLOCK, 3817 fs_info->sectorsize, 3818 SCRUB_MAX_PAGES_PER_BLOCK); 3819 return -EINVAL; 3820 } 3821 3822 /* Allocate outside of device_list_mutex */ 3823 sctx = scrub_setup_ctx(fs_info, is_dev_replace); 3824 if (IS_ERR(sctx)) 3825 return PTR_ERR(sctx); 3826 3827 mutex_lock(&fs_info->fs_devices->device_list_mutex); 3828 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true); 3829 if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) && 3830 !is_dev_replace)) { 3831 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3832 ret = -ENODEV; 3833 goto out_free_ctx; 3834 } 3835 3836 if (!is_dev_replace && !readonly && 3837 !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) { 3838 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3839 btrfs_err_in_rcu(fs_info, "scrub: device %s is not writable", 3840 rcu_str_deref(dev->name)); 3841 ret = -EROFS; 3842 goto out_free_ctx; 3843 } 3844 3845 mutex_lock(&fs_info->scrub_lock); 3846 if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || 3847 test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) { 3848 mutex_unlock(&fs_info->scrub_lock); 3849 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3850 ret = -EIO; 3851 goto out_free_ctx; 3852 } 3853 3854 down_read(&fs_info->dev_replace.rwsem); 3855 if (dev->scrub_ctx || 3856 (!is_dev_replace && 3857 btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) { 3858 up_read(&fs_info->dev_replace.rwsem); 3859 mutex_unlock(&fs_info->scrub_lock); 3860 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3861 ret = -EINPROGRESS; 3862 goto out_free_ctx; 3863 } 3864 up_read(&fs_info->dev_replace.rwsem); 3865 3866 ret = scrub_workers_get(fs_info, is_dev_replace); 3867 if (ret) { 3868 mutex_unlock(&fs_info->scrub_lock); 3869 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3870 goto out_free_ctx; 3871 } 3872 3873 sctx->readonly = readonly; 3874 dev->scrub_ctx = sctx; 3875 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3876 3877 /* 3878 * checking @scrub_pause_req here, we can avoid 3879 * race between committing transaction and scrubbing. 3880 */ 3881 __scrub_blocked_if_needed(fs_info); 3882 atomic_inc(&fs_info->scrubs_running); 3883 mutex_unlock(&fs_info->scrub_lock); 3884 3885 /* 3886 * In order to avoid deadlock with reclaim when there is a transaction 3887 * trying to pause scrub, make sure we use GFP_NOFS for all the 3888 * allocations done at btrfs_scrub_pages() and scrub_pages_for_parity() 3889 * invoked by our callees. The pausing request is done when the 3890 * transaction commit starts, and it blocks the transaction until scrub 3891 * is paused (done at specific points at scrub_stripe() or right above 3892 * before incrementing fs_info->scrubs_running). 3893 */ 3894 nofs_flag = memalloc_nofs_save(); 3895 if (!is_dev_replace) { 3896 btrfs_info(fs_info, "scrub: started on devid %llu", devid); 3897 /* 3898 * by holding device list mutex, we can 3899 * kick off writing super in log tree sync. 3900 */ 3901 mutex_lock(&fs_info->fs_devices->device_list_mutex); 3902 ret = scrub_supers(sctx, dev); 3903 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 3904 } 3905 3906 if (!ret) 3907 ret = scrub_enumerate_chunks(sctx, dev, start, end); 3908 memalloc_nofs_restore(nofs_flag); 3909 3910 wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); 3911 atomic_dec(&fs_info->scrubs_running); 3912 wake_up(&fs_info->scrub_pause_wait); 3913 3914 wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0); 3915 3916 if (progress) 3917 memcpy(progress, &sctx->stat, sizeof(*progress)); 3918 3919 if (!is_dev_replace) 3920 btrfs_info(fs_info, "scrub: %s on devid %llu with status: %d", 3921 ret ? "not finished" : "finished", devid, ret); 3922 3923 mutex_lock(&fs_info->scrub_lock); 3924 dev->scrub_ctx = NULL; 3925 if (refcount_dec_and_test(&fs_info->scrub_workers_refcnt)) { 3926 scrub_workers = fs_info->scrub_workers; 3927 scrub_wr_comp = fs_info->scrub_wr_completion_workers; 3928 scrub_parity = fs_info->scrub_parity_workers; 3929 3930 fs_info->scrub_workers = NULL; 3931 fs_info->scrub_wr_completion_workers = NULL; 3932 fs_info->scrub_parity_workers = NULL; 3933 } 3934 mutex_unlock(&fs_info->scrub_lock); 3935 3936 btrfs_destroy_workqueue(scrub_workers); 3937 btrfs_destroy_workqueue(scrub_wr_comp); 3938 btrfs_destroy_workqueue(scrub_parity); 3939 scrub_put_ctx(sctx); 3940 3941 return ret; 3942 3943 out_free_ctx: 3944 scrub_free_ctx(sctx); 3945 3946 return ret; 3947 } 3948 3949 void btrfs_scrub_pause(struct btrfs_fs_info *fs_info) 3950 { 3951 mutex_lock(&fs_info->scrub_lock); 3952 atomic_inc(&fs_info->scrub_pause_req); 3953 while (atomic_read(&fs_info->scrubs_paused) != 3954 atomic_read(&fs_info->scrubs_running)) { 3955 mutex_unlock(&fs_info->scrub_lock); 3956 wait_event(fs_info->scrub_pause_wait, 3957 atomic_read(&fs_info->scrubs_paused) == 3958 atomic_read(&fs_info->scrubs_running)); 3959 mutex_lock(&fs_info->scrub_lock); 3960 } 3961 mutex_unlock(&fs_info->scrub_lock); 3962 } 3963 3964 void btrfs_scrub_continue(struct btrfs_fs_info *fs_info) 3965 { 3966 atomic_dec(&fs_info->scrub_pause_req); 3967 wake_up(&fs_info->scrub_pause_wait); 3968 } 3969 3970 int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info) 3971 { 3972 mutex_lock(&fs_info->scrub_lock); 3973 if (!atomic_read(&fs_info->scrubs_running)) { 3974 mutex_unlock(&fs_info->scrub_lock); 3975 return -ENOTCONN; 3976 } 3977 3978 atomic_inc(&fs_info->scrub_cancel_req); 3979 while (atomic_read(&fs_info->scrubs_running)) { 3980 mutex_unlock(&fs_info->scrub_lock); 3981 wait_event(fs_info->scrub_pause_wait, 3982 atomic_read(&fs_info->scrubs_running) == 0); 3983 mutex_lock(&fs_info->scrub_lock); 3984 } 3985 atomic_dec(&fs_info->scrub_cancel_req); 3986 mutex_unlock(&fs_info->scrub_lock); 3987 3988 return 0; 3989 } 3990 3991 int btrfs_scrub_cancel_dev(struct btrfs_device *dev) 3992 { 3993 struct btrfs_fs_info *fs_info = dev->fs_info; 3994 struct scrub_ctx *sctx; 3995 3996 mutex_lock(&fs_info->scrub_lock); 3997 sctx = dev->scrub_ctx; 3998 if (!sctx) { 3999 mutex_unlock(&fs_info->scrub_lock); 4000 return -ENOTCONN; 4001 } 4002 atomic_inc(&sctx->cancel_req); 4003 while (dev->scrub_ctx) { 4004 mutex_unlock(&fs_info->scrub_lock); 4005 wait_event(fs_info->scrub_pause_wait, 4006 dev->scrub_ctx == NULL); 4007 mutex_lock(&fs_info->scrub_lock); 4008 } 4009 mutex_unlock(&fs_info->scrub_lock); 4010 4011 return 0; 4012 } 4013 4014 int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid, 4015 struct btrfs_scrub_progress *progress) 4016 { 4017 struct btrfs_device *dev; 4018 struct scrub_ctx *sctx = NULL; 4019 4020 mutex_lock(&fs_info->fs_devices->device_list_mutex); 4021 dev = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true); 4022 if (dev) 4023 sctx = dev->scrub_ctx; 4024 if (sctx) 4025 memcpy(progress, &sctx->stat, sizeof(*progress)); 4026 mutex_unlock(&fs_info->fs_devices->device_list_mutex); 4027 4028 return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV; 4029 } 4030 4031 static void scrub_remap_extent(struct btrfs_fs_info *fs_info, 4032 u64 extent_logical, u64 extent_len, 4033 u64 *extent_physical, 4034 struct btrfs_device **extent_dev, 4035 int *extent_mirror_num) 4036 { 4037 u64 mapped_length; 4038 struct btrfs_bio *bbio = NULL; 4039 int ret; 4040 4041 mapped_length = extent_len; 4042 ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, extent_logical, 4043 &mapped_length, &bbio, 0); 4044 if (ret || !bbio || mapped_length < extent_len || 4045 !bbio->stripes[0].dev->bdev) { 4046 btrfs_put_bbio(bbio); 4047 return; 4048 } 4049 4050 *extent_physical = bbio->stripes[0].physical; 4051 *extent_mirror_num = bbio->mirror_num; 4052 *extent_dev = bbio->stripes[0].dev; 4053 btrfs_put_bbio(bbio); 4054 } 4055