// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2011, 2012 STRATO. All rights reserved. */ #include #include #include #include #include "ctree.h" #include "discard.h" #include "volumes.h" #include "disk-io.h" #include "ordered-data.h" #include "transaction.h" #include "backref.h" #include "extent_io.h" #include "dev-replace.h" #include "check-integrity.h" #include "raid56.h" #include "block-group.h" #include "zoned.h" #include "fs.h" #include "accessors.h" #include "file-item.h" #include "scrub.h" /* * This is only the first step towards a full-features scrub. It reads all * extent and super block and verifies the checksums. In case a bad checksum * is found or the extent cannot be read, good data will be written back if * any can be found. * * Future enhancements: * - In case an unrepairable extent is encountered, track which files are * affected and report them * - track and record media errors, throw out bad devices * - add a mode to also read unallocated space */ struct scrub_block; struct scrub_ctx; /* * The following three values only influence the performance. * * The last one configures the number of parallel and outstanding I/O * operations. The first one configures an upper limit for the number * of (dynamically allocated) pages that are added to a bio. */ #define SCRUB_SECTORS_PER_BIO 32 /* 128KiB per bio for 4KiB pages */ #define SCRUB_BIOS_PER_SCTX 64 /* 8MiB per device in flight for 4KiB pages */ #define SCRUB_STRIPES_PER_SCTX 8 /* That would be 8 64K stripe per-device. */ /* * The following value times PAGE_SIZE needs to be large enough to match the * largest node/leaf/sector size that shall be supported. */ #define SCRUB_MAX_SECTORS_PER_BLOCK (BTRFS_MAX_METADATA_BLOCKSIZE / SZ_4K) #define SCRUB_MAX_PAGES (DIV_ROUND_UP(BTRFS_MAX_METADATA_BLOCKSIZE, PAGE_SIZE)) /* * Maximum number of mirrors that can be available for all profiles counting * the target device of dev-replace as one. During an active device replace * procedure, the target device of the copy operation is a mirror for the * filesystem data as well that can be used to read data in order to repair * read errors on other disks. * * Current value is derived from RAID1C4 with 4 copies. */ #define BTRFS_MAX_MIRRORS (4 + 1) /* Represent one sector and its needed info to verify the content. */ struct scrub_sector_verification { bool is_metadata; union { /* * Csum pointer for data csum verification. Should point to a * sector csum inside scrub_stripe::csums. * * NULL if this data sector has no csum. */ u8 *csum; /* * Extra info for metadata verification. All sectors inside a * tree block share the same generation. */ u64 generation; }; }; enum scrub_stripe_flags { /* Set when @mirror_num, @dev, @physical and @logical are set. */ SCRUB_STRIPE_FLAG_INITIALIZED, /* Set when the read-repair is finished. */ SCRUB_STRIPE_FLAG_REPAIR_DONE, }; #define SCRUB_STRIPE_PAGES (BTRFS_STRIPE_LEN / PAGE_SIZE) /* * Represent one contiguous range with a length of BTRFS_STRIPE_LEN. */ struct scrub_stripe { struct scrub_ctx *sctx; struct btrfs_block_group *bg; struct page *pages[SCRUB_STRIPE_PAGES]; struct scrub_sector_verification *sectors; struct btrfs_device *dev; u64 logical; u64 physical; u16 mirror_num; /* Should be BTRFS_STRIPE_LEN / sectorsize. */ u16 nr_sectors; /* * How many data/meta extents are in this stripe. Only for scrub status * reporting purposes. */ u16 nr_data_extents; u16 nr_meta_extents; atomic_t pending_io; wait_queue_head_t io_wait; wait_queue_head_t repair_wait; /* * Indicate the states of the stripe. Bits are defined in * scrub_stripe_flags enum. */ unsigned long state; /* Indicate which sectors are covered by extent items. */ unsigned long extent_sector_bitmap; /* * The errors hit during the initial read of the stripe. * * Would be utilized for error reporting and repair. */ unsigned long init_error_bitmap; /* * The following error bitmaps are all for the current status. * Every time we submit a new read, these bitmaps may be updated. * * error_bitmap = io_error_bitmap | csum_error_bitmap | meta_error_bitmap; * * IO and csum errors can happen for both metadata and data. */ unsigned long error_bitmap; unsigned long io_error_bitmap; unsigned long csum_error_bitmap; unsigned long meta_error_bitmap; /* For writeback (repair or replace) error reporting. */ unsigned long write_error_bitmap; /* Writeback can be concurrent, thus we need to protect the bitmap. */ spinlock_t write_error_lock; /* * Checksum for the whole stripe if this stripe is inside a data block * group. */ u8 *csums; struct work_struct work; }; struct scrub_recover { refcount_t refs; struct btrfs_io_context *bioc; u64 map_length; }; struct scrub_sector { struct scrub_block *sblock; struct list_head list; u64 flags; /* extent flags */ u64 generation; /* Offset in bytes to @sblock. */ u32 offset; atomic_t refs; unsigned int have_csum:1; unsigned int io_error:1; u8 csum[BTRFS_CSUM_SIZE]; struct scrub_recover *recover; }; struct scrub_bio { int index; struct scrub_ctx *sctx; struct btrfs_device *dev; struct bio *bio; blk_status_t status; u64 logical; u64 physical; struct scrub_sector *sectors[SCRUB_SECTORS_PER_BIO]; int sector_count; int next_free; struct work_struct work; }; struct scrub_block { /* * Each page will have its page::private used to record the logical * bytenr. */ struct page *pages[SCRUB_MAX_PAGES]; struct scrub_sector *sectors[SCRUB_MAX_SECTORS_PER_BLOCK]; struct btrfs_device *dev; /* Logical bytenr of the sblock */ u64 logical; u64 physical; u64 physical_for_dev_replace; /* Length of sblock in bytes */ u32 len; int sector_count; int mirror_num; atomic_t outstanding_sectors; refcount_t refs; /* free mem on transition to zero */ struct scrub_ctx *sctx; struct scrub_parity *sparity; struct { unsigned int header_error:1; unsigned int checksum_error:1; unsigned int no_io_error_seen:1; unsigned int generation_error:1; /* also sets header_error */ /* The following is for the data used to check parity */ /* It is for the data with checksum */ unsigned int data_corrected:1; }; struct work_struct work; }; /* Used for the chunks with parity stripe such RAID5/6 */ struct scrub_parity { struct scrub_ctx *sctx; struct btrfs_device *scrub_dev; u64 logic_start; u64 logic_end; int nsectors; u32 stripe_len; refcount_t refs; struct list_head sectors_list; /* Work of parity check and repair */ struct work_struct work; /* Mark the parity blocks which have data */ unsigned long dbitmap; /* * Mark the parity blocks which have data, but errors happen when * read data or check data */ unsigned long ebitmap; }; struct scrub_ctx { struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX]; struct scrub_stripe stripes[SCRUB_STRIPES_PER_SCTX]; struct btrfs_fs_info *fs_info; int first_free; int curr; int cur_stripe; atomic_t bios_in_flight; atomic_t workers_pending; spinlock_t list_lock; wait_queue_head_t list_wait; struct list_head csum_list; atomic_t cancel_req; int readonly; int sectors_per_bio; /* State of IO submission throttling affecting the associated device */ ktime_t throttle_deadline; u64 throttle_sent; int is_dev_replace; u64 write_pointer; struct scrub_bio *wr_curr_bio; struct mutex wr_lock; struct btrfs_device *wr_tgtdev; bool flush_all_writes; /* * statistics */ struct btrfs_scrub_progress stat; spinlock_t stat_lock; /* * Use a ref counter to avoid use-after-free issues. Scrub workers * decrement bios_in_flight and workers_pending and then do a wakeup * on the list_wait wait queue. We must ensure the main scrub task * doesn't free the scrub context before or while the workers are * doing the wakeup() call. */ refcount_t refs; }; struct scrub_warning { struct btrfs_path *path; u64 extent_item_size; const char *errstr; u64 physical; u64 logical; struct btrfs_device *dev; }; struct full_stripe_lock { struct rb_node node; u64 logical; u64 refs; struct mutex mutex; }; #ifndef CONFIG_64BIT /* This structure is for architectures whose (void *) is smaller than u64 */ struct scrub_page_private { u64 logical; }; #endif static int attach_scrub_page_private(struct page *page, u64 logical) { #ifdef CONFIG_64BIT attach_page_private(page, (void *)logical); return 0; #else struct scrub_page_private *spp; spp = kmalloc(sizeof(*spp), GFP_KERNEL); if (!spp) return -ENOMEM; spp->logical = logical; attach_page_private(page, (void *)spp); return 0; #endif } static void detach_scrub_page_private(struct page *page) { #ifdef CONFIG_64BIT detach_page_private(page); return; #else struct scrub_page_private *spp; spp = detach_page_private(page); kfree(spp); return; #endif } static void release_scrub_stripe(struct scrub_stripe *stripe) { if (!stripe) return; for (int i = 0; i < SCRUB_STRIPE_PAGES; i++) { if (stripe->pages[i]) __free_page(stripe->pages[i]); stripe->pages[i] = NULL; } kfree(stripe->sectors); kfree(stripe->csums); stripe->sectors = NULL; stripe->csums = NULL; stripe->sctx = NULL; stripe->state = 0; } static int init_scrub_stripe(struct btrfs_fs_info *fs_info, struct scrub_stripe *stripe) { int ret; memset(stripe, 0, sizeof(*stripe)); stripe->nr_sectors = BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits; stripe->state = 0; init_waitqueue_head(&stripe->io_wait); init_waitqueue_head(&stripe->repair_wait); atomic_set(&stripe->pending_io, 0); spin_lock_init(&stripe->write_error_lock); ret = btrfs_alloc_page_array(SCRUB_STRIPE_PAGES, stripe->pages); if (ret < 0) goto error; stripe->sectors = kcalloc(stripe->nr_sectors, sizeof(struct scrub_sector_verification), GFP_KERNEL); if (!stripe->sectors) goto error; stripe->csums = kcalloc(BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits, fs_info->csum_size, GFP_KERNEL); if (!stripe->csums) goto error; return 0; error: release_scrub_stripe(stripe); return -ENOMEM; } static void wait_scrub_stripe_io(struct scrub_stripe *stripe) { wait_event(stripe->io_wait, atomic_read(&stripe->pending_io) == 0); } static struct scrub_block *alloc_scrub_block(struct scrub_ctx *sctx, struct btrfs_device *dev, u64 logical, u64 physical, u64 physical_for_dev_replace, int mirror_num) { struct scrub_block *sblock; sblock = kzalloc(sizeof(*sblock), GFP_KERNEL); if (!sblock) return NULL; refcount_set(&sblock->refs, 1); sblock->sctx = sctx; sblock->logical = logical; sblock->physical = physical; sblock->physical_for_dev_replace = physical_for_dev_replace; sblock->dev = dev; sblock->mirror_num = mirror_num; sblock->no_io_error_seen = 1; /* * Scrub_block::pages will be allocated at alloc_scrub_sector() when * the corresponding page is not allocated. */ return sblock; } /* * Allocate a new scrub sector and attach it to @sblock. * * Will also allocate new pages for @sblock if needed. */ static struct scrub_sector *alloc_scrub_sector(struct scrub_block *sblock, u64 logical) { const pgoff_t page_index = (logical - sblock->logical) >> PAGE_SHIFT; struct scrub_sector *ssector; /* We must never have scrub_block exceed U32_MAX in size. */ ASSERT(logical - sblock->logical < U32_MAX); ssector = kzalloc(sizeof(*ssector), GFP_KERNEL); if (!ssector) return NULL; /* Allocate a new page if the slot is not allocated */ if (!sblock->pages[page_index]) { int ret; sblock->pages[page_index] = alloc_page(GFP_KERNEL); if (!sblock->pages[page_index]) { kfree(ssector); return NULL; } ret = attach_scrub_page_private(sblock->pages[page_index], sblock->logical + (page_index << PAGE_SHIFT)); if (ret < 0) { kfree(ssector); __free_page(sblock->pages[page_index]); sblock->pages[page_index] = NULL; return NULL; } } atomic_set(&ssector->refs, 1); ssector->sblock = sblock; /* The sector to be added should not be used */ ASSERT(sblock->sectors[sblock->sector_count] == NULL); ssector->offset = logical - sblock->logical; /* The sector count must be smaller than the limit */ ASSERT(sblock->sector_count < SCRUB_MAX_SECTORS_PER_BLOCK); sblock->sectors[sblock->sector_count] = ssector; sblock->sector_count++; sblock->len += sblock->sctx->fs_info->sectorsize; return ssector; } static struct page *scrub_sector_get_page(struct scrub_sector *ssector) { struct scrub_block *sblock = ssector->sblock; pgoff_t index; /* * When calling this function, ssector must be alreaday attached to the * parent sblock. */ ASSERT(sblock); /* The range should be inside the sblock range */ ASSERT(ssector->offset < sblock->len); index = ssector->offset >> PAGE_SHIFT; ASSERT(index < SCRUB_MAX_PAGES); ASSERT(sblock->pages[index]); ASSERT(PagePrivate(sblock->pages[index])); return sblock->pages[index]; } static unsigned int scrub_sector_get_page_offset(struct scrub_sector *ssector) { struct scrub_block *sblock = ssector->sblock; /* * When calling this function, ssector must be already attached to the * parent sblock. */ ASSERT(sblock); /* The range should be inside the sblock range */ ASSERT(ssector->offset < sblock->len); return offset_in_page(ssector->offset); } static char *scrub_sector_get_kaddr(struct scrub_sector *ssector) { return page_address(scrub_sector_get_page(ssector)) + scrub_sector_get_page_offset(ssector); } static int bio_add_scrub_sector(struct bio *bio, struct scrub_sector *ssector, unsigned int len) { return bio_add_page(bio, scrub_sector_get_page(ssector), len, scrub_sector_get_page_offset(ssector)); } static int scrub_setup_recheck_block(struct scrub_block *original_sblock, struct scrub_block *sblocks_for_recheck[]); static void scrub_recheck_block(struct btrfs_fs_info *fs_info, struct scrub_block *sblock, int retry_failed_mirror); static void scrub_recheck_block_checksum(struct scrub_block *sblock); static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, struct scrub_block *sblock_good); static int scrub_repair_sector_from_good_copy(struct scrub_block *sblock_bad, struct scrub_block *sblock_good, int sector_num, int force_write); static void scrub_write_block_to_dev_replace(struct scrub_block *sblock); static int scrub_write_sector_to_dev_replace(struct scrub_block *sblock, int sector_num); static int scrub_checksum_data(struct scrub_block *sblock); static int scrub_checksum_tree_block(struct scrub_block *sblock); static int scrub_checksum_super(struct scrub_block *sblock); static void scrub_block_put(struct scrub_block *sblock); static void scrub_sector_get(struct scrub_sector *sector); static void scrub_sector_put(struct scrub_sector *sector); static void scrub_parity_get(struct scrub_parity *sparity); static void scrub_parity_put(struct scrub_parity *sparity); static void scrub_bio_end_io(struct bio *bio); static void scrub_bio_end_io_worker(struct work_struct *work); static void scrub_block_complete(struct scrub_block *sblock); static int scrub_add_sector_to_wr_bio(struct scrub_ctx *sctx, struct scrub_sector *sector); static void scrub_wr_submit(struct scrub_ctx *sctx); static void scrub_wr_bio_end_io(struct bio *bio); static void scrub_wr_bio_end_io_worker(struct work_struct *work); static void scrub_put_ctx(struct scrub_ctx *sctx); static inline int scrub_is_page_on_raid56(struct scrub_sector *sector) { return sector->recover && (sector->recover->bioc->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK); } static void scrub_pending_bio_inc(struct scrub_ctx *sctx) { refcount_inc(&sctx->refs); atomic_inc(&sctx->bios_in_flight); } static void scrub_pending_bio_dec(struct scrub_ctx *sctx) { atomic_dec(&sctx->bios_in_flight); wake_up(&sctx->list_wait); scrub_put_ctx(sctx); } static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info) { while (atomic_read(&fs_info->scrub_pause_req)) { mutex_unlock(&fs_info->scrub_lock); wait_event(fs_info->scrub_pause_wait, atomic_read(&fs_info->scrub_pause_req) == 0); mutex_lock(&fs_info->scrub_lock); } } static void scrub_pause_on(struct btrfs_fs_info *fs_info) { atomic_inc(&fs_info->scrubs_paused); wake_up(&fs_info->scrub_pause_wait); } static void scrub_pause_off(struct btrfs_fs_info *fs_info) { mutex_lock(&fs_info->scrub_lock); __scrub_blocked_if_needed(fs_info); atomic_dec(&fs_info->scrubs_paused); mutex_unlock(&fs_info->scrub_lock); wake_up(&fs_info->scrub_pause_wait); } static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info) { scrub_pause_on(fs_info); scrub_pause_off(fs_info); } /* * Insert new full stripe lock into full stripe locks tree * * Return pointer to existing or newly inserted full_stripe_lock structure if * everything works well. * Return ERR_PTR(-ENOMEM) if we failed to allocate memory * * NOTE: caller must hold full_stripe_locks_root->lock before calling this * function */ static struct full_stripe_lock *insert_full_stripe_lock( struct btrfs_full_stripe_locks_tree *locks_root, u64 fstripe_logical) { struct rb_node **p; struct rb_node *parent = NULL; struct full_stripe_lock *entry; struct full_stripe_lock *ret; lockdep_assert_held(&locks_root->lock); p = &locks_root->root.rb_node; while (*p) { parent = *p; entry = rb_entry(parent, struct full_stripe_lock, node); if (fstripe_logical < entry->logical) { p = &(*p)->rb_left; } else if (fstripe_logical > entry->logical) { p = &(*p)->rb_right; } else { entry->refs++; return entry; } } /* * Insert new lock. */ ret = kmalloc(sizeof(*ret), GFP_KERNEL); if (!ret) return ERR_PTR(-ENOMEM); ret->logical = fstripe_logical; ret->refs = 1; mutex_init(&ret->mutex); rb_link_node(&ret->node, parent, p); rb_insert_color(&ret->node, &locks_root->root); return ret; } /* * Search for a full stripe lock of a block group * * Return pointer to existing full stripe lock if found * Return NULL if not found */ static struct full_stripe_lock *search_full_stripe_lock( struct btrfs_full_stripe_locks_tree *locks_root, u64 fstripe_logical) { struct rb_node *node; struct full_stripe_lock *entry; lockdep_assert_held(&locks_root->lock); node = locks_root->root.rb_node; while (node) { entry = rb_entry(node, struct full_stripe_lock, node); if (fstripe_logical < entry->logical) node = node->rb_left; else if (fstripe_logical > entry->logical) node = node->rb_right; else return entry; } return NULL; } /* * Helper to get full stripe logical from a normal bytenr. * * Caller must ensure @cache is a RAID56 block group. */ static u64 get_full_stripe_logical(struct btrfs_block_group *cache, u64 bytenr) { u64 ret; /* * Due to chunk item size limit, full stripe length should not be * larger than U32_MAX. Just a sanity check here. */ WARN_ON_ONCE(cache->full_stripe_len >= U32_MAX); /* * round_down() can only handle power of 2, while RAID56 full * stripe length can be 64KiB * n, so we need to manually round down. */ ret = div64_u64(bytenr - cache->start, cache->full_stripe_len) * cache->full_stripe_len + cache->start; return ret; } /* * Lock a full stripe to avoid concurrency of recovery and read * * It's only used for profiles with parities (RAID5/6), for other profiles it * does nothing. * * Return 0 if we locked full stripe covering @bytenr, with a mutex held. * So caller must call unlock_full_stripe() at the same context. * * Return <0 if encounters error. */ static int lock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr, bool *locked_ret) { struct btrfs_block_group *bg_cache; struct btrfs_full_stripe_locks_tree *locks_root; struct full_stripe_lock *existing; u64 fstripe_start; int ret = 0; *locked_ret = false; bg_cache = btrfs_lookup_block_group(fs_info, bytenr); if (!bg_cache) { ASSERT(0); return -ENOENT; } /* Profiles not based on parity don't need full stripe lock */ if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK)) goto out; locks_root = &bg_cache->full_stripe_locks_root; fstripe_start = get_full_stripe_logical(bg_cache, bytenr); /* Now insert the full stripe lock */ mutex_lock(&locks_root->lock); existing = insert_full_stripe_lock(locks_root, fstripe_start); mutex_unlock(&locks_root->lock); if (IS_ERR(existing)) { ret = PTR_ERR(existing); goto out; } mutex_lock(&existing->mutex); *locked_ret = true; out: btrfs_put_block_group(bg_cache); return ret; } /* * Unlock a full stripe. * * NOTE: Caller must ensure it's the same context calling corresponding * lock_full_stripe(). * * Return 0 if we unlock full stripe without problem. * Return <0 for error */ static int unlock_full_stripe(struct btrfs_fs_info *fs_info, u64 bytenr, bool locked) { struct btrfs_block_group *bg_cache; struct btrfs_full_stripe_locks_tree *locks_root; struct full_stripe_lock *fstripe_lock; u64 fstripe_start; bool freeit = false; int ret = 0; /* If we didn't acquire full stripe lock, no need to continue */ if (!locked) return 0; bg_cache = btrfs_lookup_block_group(fs_info, bytenr); if (!bg_cache) { ASSERT(0); return -ENOENT; } if (!(bg_cache->flags & BTRFS_BLOCK_GROUP_RAID56_MASK)) goto out; locks_root = &bg_cache->full_stripe_locks_root; fstripe_start = get_full_stripe_logical(bg_cache, bytenr); mutex_lock(&locks_root->lock); fstripe_lock = search_full_stripe_lock(locks_root, fstripe_start); /* Unpaired unlock_full_stripe() detected */ if (!fstripe_lock) { WARN_ON(1); ret = -ENOENT; mutex_unlock(&locks_root->lock); goto out; } if (fstripe_lock->refs == 0) { WARN_ON(1); btrfs_warn(fs_info, "full stripe lock at %llu refcount underflow", fstripe_lock->logical); } else { fstripe_lock->refs--; } if (fstripe_lock->refs == 0) { rb_erase(&fstripe_lock->node, &locks_root->root); freeit = true; } mutex_unlock(&locks_root->lock); mutex_unlock(&fstripe_lock->mutex); if (freeit) kfree(fstripe_lock); out: btrfs_put_block_group(bg_cache); return ret; } static void scrub_free_csums(struct scrub_ctx *sctx) { while (!list_empty(&sctx->csum_list)) { struct btrfs_ordered_sum *sum; sum = list_first_entry(&sctx->csum_list, struct btrfs_ordered_sum, list); list_del(&sum->list); kfree(sum); } } static noinline_for_stack void scrub_free_ctx(struct scrub_ctx *sctx) { int i; if (!sctx) return; /* this can happen when scrub is cancelled */ if (sctx->curr != -1) { struct scrub_bio *sbio = sctx->bios[sctx->curr]; for (i = 0; i < sbio->sector_count; i++) scrub_block_put(sbio->sectors[i]->sblock); bio_put(sbio->bio); } for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) { struct scrub_bio *sbio = sctx->bios[i]; if (!sbio) break; kfree(sbio); } for (i = 0; i < SCRUB_STRIPES_PER_SCTX; i++) release_scrub_stripe(&sctx->stripes[i]); kfree(sctx->wr_curr_bio); scrub_free_csums(sctx); kfree(sctx); } static void scrub_put_ctx(struct scrub_ctx *sctx) { if (refcount_dec_and_test(&sctx->refs)) scrub_free_ctx(sctx); } static noinline_for_stack struct scrub_ctx *scrub_setup_ctx( struct btrfs_fs_info *fs_info, int is_dev_replace) { struct scrub_ctx *sctx; int i; sctx = kzalloc(sizeof(*sctx), GFP_KERNEL); if (!sctx) goto nomem; refcount_set(&sctx->refs, 1); sctx->is_dev_replace = is_dev_replace; sctx->sectors_per_bio = SCRUB_SECTORS_PER_BIO; sctx->curr = -1; sctx->fs_info = fs_info; INIT_LIST_HEAD(&sctx->csum_list); for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) { struct scrub_bio *sbio; sbio = kzalloc(sizeof(*sbio), GFP_KERNEL); if (!sbio) goto nomem; sctx->bios[i] = sbio; sbio->index = i; sbio->sctx = sctx; sbio->sector_count = 0; INIT_WORK(&sbio->work, scrub_bio_end_io_worker); if (i != SCRUB_BIOS_PER_SCTX - 1) sctx->bios[i]->next_free = i + 1; else sctx->bios[i]->next_free = -1; } for (i = 0; i < SCRUB_STRIPES_PER_SCTX; i++) { int ret; ret = init_scrub_stripe(fs_info, &sctx->stripes[i]); if (ret < 0) goto nomem; sctx->stripes[i].sctx = sctx; } sctx->first_free = 0; atomic_set(&sctx->bios_in_flight, 0); atomic_set(&sctx->workers_pending, 0); atomic_set(&sctx->cancel_req, 0); spin_lock_init(&sctx->list_lock); spin_lock_init(&sctx->stat_lock); init_waitqueue_head(&sctx->list_wait); sctx->throttle_deadline = 0; WARN_ON(sctx->wr_curr_bio != NULL); mutex_init(&sctx->wr_lock); sctx->wr_curr_bio = NULL; if (is_dev_replace) { WARN_ON(!fs_info->dev_replace.tgtdev); sctx->wr_tgtdev = fs_info->dev_replace.tgtdev; sctx->flush_all_writes = false; } return sctx; nomem: scrub_free_ctx(sctx); return ERR_PTR(-ENOMEM); } static int scrub_print_warning_inode(u64 inum, u64 offset, u64 num_bytes, u64 root, void *warn_ctx) { u32 nlink; int ret; int i; unsigned nofs_flag; struct extent_buffer *eb; struct btrfs_inode_item *inode_item; struct scrub_warning *swarn = warn_ctx; struct btrfs_fs_info *fs_info = swarn->dev->fs_info; struct inode_fs_paths *ipath = NULL; struct btrfs_root *local_root; struct btrfs_key key; local_root = btrfs_get_fs_root(fs_info, root, true); if (IS_ERR(local_root)) { ret = PTR_ERR(local_root); goto err; } /* * this makes the path point to (inum INODE_ITEM ioff) */ key.objectid = inum; key.type = BTRFS_INODE_ITEM_KEY; key.offset = 0; ret = btrfs_search_slot(NULL, local_root, &key, swarn->path, 0, 0); if (ret) { btrfs_put_root(local_root); btrfs_release_path(swarn->path); goto err; } eb = swarn->path->nodes[0]; inode_item = btrfs_item_ptr(eb, swarn->path->slots[0], struct btrfs_inode_item); nlink = btrfs_inode_nlink(eb, inode_item); btrfs_release_path(swarn->path); /* * init_path might indirectly call vmalloc, or use GFP_KERNEL. Scrub * uses GFP_NOFS in this context, so we keep it consistent but it does * not seem to be strictly necessary. */ nofs_flag = memalloc_nofs_save(); ipath = init_ipath(4096, local_root, swarn->path); memalloc_nofs_restore(nofs_flag); if (IS_ERR(ipath)) { btrfs_put_root(local_root); ret = PTR_ERR(ipath); ipath = NULL; goto err; } ret = paths_from_inode(inum, ipath); if (ret < 0) goto err; /* * we deliberately ignore the bit ipath might have been too small to * hold all of the paths here */ for (i = 0; i < ipath->fspath->elem_cnt; ++i) btrfs_warn_in_rcu(fs_info, "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu, length %u, links %u (path: %s)", swarn->errstr, swarn->logical, btrfs_dev_name(swarn->dev), swarn->physical, root, inum, offset, fs_info->sectorsize, nlink, (char *)(unsigned long)ipath->fspath->val[i]); btrfs_put_root(local_root); free_ipath(ipath); return 0; err: btrfs_warn_in_rcu(fs_info, "%s at logical %llu on dev %s, physical %llu, root %llu, inode %llu, offset %llu: path resolving failed with ret=%d", swarn->errstr, swarn->logical, btrfs_dev_name(swarn->dev), swarn->physical, root, inum, offset, ret); free_ipath(ipath); return 0; } static void scrub_print_common_warning(const char *errstr, struct btrfs_device *dev, bool is_super, u64 logical, u64 physical) { struct btrfs_fs_info *fs_info = dev->fs_info; struct btrfs_path *path; struct btrfs_key found_key; struct extent_buffer *eb; struct btrfs_extent_item *ei; struct scrub_warning swarn; unsigned long ptr = 0; u64 flags = 0; u64 ref_root; u32 item_size; u8 ref_level = 0; int ret; /* Super block error, no need to search extent tree. */ if (is_super) { btrfs_warn_in_rcu(fs_info, "%s on device %s, physical %llu", errstr, btrfs_dev_name(dev), physical); return; } path = btrfs_alloc_path(); if (!path) return; swarn.physical = physical; swarn.logical = logical; swarn.errstr = errstr; swarn.dev = NULL; ret = extent_from_logical(fs_info, swarn.logical, path, &found_key, &flags); if (ret < 0) goto out; swarn.extent_item_size = found_key.offset; eb = path->nodes[0]; ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item); item_size = btrfs_item_size(eb, path->slots[0]); if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { do { ret = tree_backref_for_extent(&ptr, eb, &found_key, ei, item_size, &ref_root, &ref_level); btrfs_warn_in_rcu(fs_info, "%s at logical %llu on dev %s, physical %llu: metadata %s (level %d) in tree %llu", errstr, swarn.logical, btrfs_dev_name(dev), swarn.physical, ref_level ? "node" : "leaf", ret < 0 ? -1 : ref_level, ret < 0 ? -1 : ref_root); } while (ret != 1); btrfs_release_path(path); } else { struct btrfs_backref_walk_ctx ctx = { 0 }; btrfs_release_path(path); ctx.bytenr = found_key.objectid; ctx.extent_item_pos = swarn.logical - found_key.objectid; ctx.fs_info = fs_info; swarn.path = path; swarn.dev = dev; iterate_extent_inodes(&ctx, true, scrub_print_warning_inode, &swarn); } out: btrfs_free_path(path); } static void scrub_print_warning(const char *errstr, struct scrub_block *sblock) { scrub_print_common_warning(errstr, sblock->dev, sblock->sectors[0]->flags & BTRFS_EXTENT_FLAG_SUPER, sblock->logical, sblock->physical); } static inline void scrub_get_recover(struct scrub_recover *recover) { refcount_inc(&recover->refs); } static inline void scrub_put_recover(struct btrfs_fs_info *fs_info, struct scrub_recover *recover) { if (refcount_dec_and_test(&recover->refs)) { btrfs_bio_counter_dec(fs_info); btrfs_put_bioc(recover->bioc); kfree(recover); } } /* * scrub_handle_errored_block gets called when either verification of the * sectors failed or the bio failed to read, e.g. with EIO. In the latter * case, this function handles all sectors in the bio, even though only one * may be bad. * The goal of this function is to repair the errored block by using the * contents of one of the mirrors. */ static int scrub_handle_errored_block(struct scrub_block *sblock_to_check) { struct scrub_ctx *sctx = sblock_to_check->sctx; struct btrfs_device *dev = sblock_to_check->dev; struct btrfs_fs_info *fs_info; u64 logical; unsigned int failed_mirror_index; unsigned int is_metadata; unsigned int have_csum; /* One scrub_block for each mirror */ struct scrub_block *sblocks_for_recheck[BTRFS_MAX_MIRRORS] = { 0 }; struct scrub_block *sblock_bad; int ret; int mirror_index; int sector_num; int success; bool full_stripe_locked; unsigned int nofs_flag; static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); BUG_ON(sblock_to_check->sector_count < 1); fs_info = sctx->fs_info; if (sblock_to_check->sectors[0]->flags & BTRFS_EXTENT_FLAG_SUPER) { /* * If we find an error in a super block, we just report it. * They will get written with the next transaction commit * anyway */ scrub_print_warning("super block error", sblock_to_check); spin_lock(&sctx->stat_lock); ++sctx->stat.super_errors; spin_unlock(&sctx->stat_lock); btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS); return 0; } logical = sblock_to_check->logical; ASSERT(sblock_to_check->mirror_num); failed_mirror_index = sblock_to_check->mirror_num - 1; is_metadata = !(sblock_to_check->sectors[0]->flags & BTRFS_EXTENT_FLAG_DATA); have_csum = sblock_to_check->sectors[0]->have_csum; if (!sctx->is_dev_replace && btrfs_repair_one_zone(fs_info, logical)) return 0; /* * We must use GFP_NOFS because the scrub task might be waiting for a * worker task executing this function and in turn a transaction commit * might be waiting the scrub task to pause (which needs to wait for all * the worker tasks to complete before pausing). * We do allocations in the workers through insert_full_stripe_lock() * and scrub_add_sector_to_wr_bio(), which happens down the call chain of * this function. */ nofs_flag = memalloc_nofs_save(); /* * For RAID5/6, race can happen for a different device scrub thread. * For data corruption, Parity and Data threads will both try * to recovery the data. * Race can lead to doubly added csum error, or even unrecoverable * error. */ ret = lock_full_stripe(fs_info, logical, &full_stripe_locked); if (ret < 0) { memalloc_nofs_restore(nofs_flag); spin_lock(&sctx->stat_lock); if (ret == -ENOMEM) sctx->stat.malloc_errors++; sctx->stat.read_errors++; sctx->stat.uncorrectable_errors++; spin_unlock(&sctx->stat_lock); return ret; } /* * read all mirrors one after the other. This includes to * re-read the extent or metadata block that failed (that was * the cause that this fixup code is called) another time, * sector by sector this time in order to know which sectors * caused I/O errors and which ones are good (for all mirrors). * It is the goal to handle the situation when more than one * mirror contains I/O errors, but the errors do not * overlap, i.e. the data can be repaired by selecting the * sectors from those mirrors without I/O error on the * particular sectors. One example (with blocks >= 2 * sectorsize) * would be that mirror #1 has an I/O error on the first sector, * the second sector is good, and mirror #2 has an I/O error on * the second sector, but the first sector is good. * Then the first sector of the first mirror can be repaired by * taking the first sector of the second mirror, and the * second sector of the second mirror can be repaired by * copying the contents of the 2nd sector of the 1st mirror. * One more note: if the sectors of one mirror contain I/O * errors, the checksum cannot be verified. In order to get * the best data for repairing, the first attempt is to find * a mirror without I/O errors and with a validated checksum. * Only if this is not possible, the sectors are picked from * mirrors with I/O errors without considering the checksum. * If the latter is the case, at the end, the checksum of the * repaired area is verified in order to correctly maintain * the statistics. */ for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS; mirror_index++) { /* * Note: the two members refs and outstanding_sectors are not * used in the blocks that are used for the recheck procedure. * * But alloc_scrub_block() will initialize sblock::ref anyway, * so we can use scrub_block_put() to clean them up. * * And here we don't setup the physical/dev for the sblock yet, * they will be correctly initialized in scrub_setup_recheck_block(). */ sblocks_for_recheck[mirror_index] = alloc_scrub_block(sctx, NULL, logical, 0, 0, mirror_index); if (!sblocks_for_recheck[mirror_index]) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; sctx->stat.read_errors++; sctx->stat.uncorrectable_errors++; spin_unlock(&sctx->stat_lock); btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); goto out; } } /* Setup the context, map the logical blocks and alloc the sectors */ ret = scrub_setup_recheck_block(sblock_to_check, sblocks_for_recheck); if (ret) { spin_lock(&sctx->stat_lock); sctx->stat.read_errors++; sctx->stat.uncorrectable_errors++; spin_unlock(&sctx->stat_lock); btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); goto out; } BUG_ON(failed_mirror_index >= BTRFS_MAX_MIRRORS); sblock_bad = sblocks_for_recheck[failed_mirror_index]; /* build and submit the bios for the failed mirror, check checksums */ scrub_recheck_block(fs_info, sblock_bad, 1); if (!sblock_bad->header_error && !sblock_bad->checksum_error && sblock_bad->no_io_error_seen) { /* * The error disappeared after reading sector by sector, or * the area was part of a huge bio and other parts of the * bio caused I/O errors, or the block layer merged several * read requests into one and the error is caused by a * different bio (usually one of the two latter cases is * the cause) */ spin_lock(&sctx->stat_lock); sctx->stat.unverified_errors++; sblock_to_check->data_corrected = 1; spin_unlock(&sctx->stat_lock); if (sctx->is_dev_replace) scrub_write_block_to_dev_replace(sblock_bad); goto out; } if (!sblock_bad->no_io_error_seen) { spin_lock(&sctx->stat_lock); sctx->stat.read_errors++; spin_unlock(&sctx->stat_lock); if (__ratelimit(&rs)) scrub_print_warning("i/o error", sblock_to_check); btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_READ_ERRS); } else if (sblock_bad->checksum_error) { spin_lock(&sctx->stat_lock); sctx->stat.csum_errors++; spin_unlock(&sctx->stat_lock); if (__ratelimit(&rs)) scrub_print_warning("checksum error", sblock_to_check); btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS); } else if (sblock_bad->header_error) { spin_lock(&sctx->stat_lock); sctx->stat.verify_errors++; spin_unlock(&sctx->stat_lock); if (__ratelimit(&rs)) scrub_print_warning("checksum/header error", sblock_to_check); if (sblock_bad->generation_error) btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_GENERATION_ERRS); else btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_CORRUPTION_ERRS); } if (sctx->readonly) { ASSERT(!sctx->is_dev_replace); goto out; } /* * now build and submit the bios for the other mirrors, check * checksums. * First try to pick the mirror which is completely without I/O * errors and also does not have a checksum error. * If one is found, and if a checksum is present, the full block * that is known to contain an error is rewritten. Afterwards * the block is known to be corrected. * If a mirror is found which is completely correct, and no * checksum is present, only those sectors are rewritten that had * an I/O error in the block to be repaired, since it cannot be * determined, which copy of the other sectors is better (and it * could happen otherwise that a correct sector would be * overwritten by a bad one). */ for (mirror_index = 0; ;mirror_index++) { struct scrub_block *sblock_other; if (mirror_index == failed_mirror_index) continue; /* raid56's mirror can be more than BTRFS_MAX_MIRRORS */ if (!scrub_is_page_on_raid56(sblock_bad->sectors[0])) { if (mirror_index >= BTRFS_MAX_MIRRORS) break; if (!sblocks_for_recheck[mirror_index]->sector_count) break; sblock_other = sblocks_for_recheck[mirror_index]; } else { struct scrub_recover *r = sblock_bad->sectors[0]->recover; int max_allowed = r->bioc->num_stripes - r->bioc->replace_nr_stripes; if (mirror_index >= max_allowed) break; if (!sblocks_for_recheck[1]->sector_count) break; ASSERT(failed_mirror_index == 0); sblock_other = sblocks_for_recheck[1]; sblock_other->mirror_num = 1 + mirror_index; } /* build and submit the bios, check checksums */ scrub_recheck_block(fs_info, sblock_other, 0); if (!sblock_other->header_error && !sblock_other->checksum_error && sblock_other->no_io_error_seen) { if (sctx->is_dev_replace) { scrub_write_block_to_dev_replace(sblock_other); goto corrected_error; } else { ret = scrub_repair_block_from_good_copy( sblock_bad, sblock_other); if (!ret) goto corrected_error; } } } if (sblock_bad->no_io_error_seen && !sctx->is_dev_replace) goto did_not_correct_error; /* * In case of I/O errors in the area that is supposed to be * repaired, continue by picking good copies of those sectors. * Select the good sectors from mirrors to rewrite bad sectors from * the area to fix. Afterwards verify the checksum of the block * that is supposed to be repaired. This verification step is * only done for the purpose of statistic counting and for the * final scrub report, whether errors remain. * A perfect algorithm could make use of the checksum and try * all possible combinations of sectors from the different mirrors * until the checksum verification succeeds. For example, when * the 2nd sector of mirror #1 faces I/O errors, and the 2nd sector * of mirror #2 is readable but the final checksum test fails, * then the 2nd sector of mirror #3 could be tried, whether now * the final checksum succeeds. But this would be a rare * exception and is therefore not implemented. At least it is * avoided that the good copy is overwritten. * A more useful improvement would be to pick the sectors * without I/O error based on sector sizes (512 bytes on legacy * disks) instead of on sectorsize. Then maybe 512 byte of one * mirror could be repaired by taking 512 byte of a different * mirror, even if other 512 byte sectors in the same sectorsize * area are unreadable. */ success = 1; for (sector_num = 0; sector_num < sblock_bad->sector_count; sector_num++) { struct scrub_sector *sector_bad = sblock_bad->sectors[sector_num]; struct scrub_block *sblock_other = NULL; /* Skip no-io-error sectors in scrub */ if (!sector_bad->io_error && !sctx->is_dev_replace) continue; if (scrub_is_page_on_raid56(sblock_bad->sectors[0])) { /* * In case of dev replace, if raid56 rebuild process * didn't work out correct data, then copy the content * in sblock_bad to make sure target device is identical * to source device, instead of writing garbage data in * sblock_for_recheck array to target device. */ sblock_other = NULL; } else if (sector_bad->io_error) { /* Try to find no-io-error sector in mirrors */ for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS && sblocks_for_recheck[mirror_index]->sector_count > 0; mirror_index++) { if (!sblocks_for_recheck[mirror_index]-> sectors[sector_num]->io_error) { sblock_other = sblocks_for_recheck[mirror_index]; break; } } if (!sblock_other) success = 0; } if (sctx->is_dev_replace) { /* * Did not find a mirror to fetch the sector from. * scrub_write_sector_to_dev_replace() handles this * case (sector->io_error), by filling the block with * zeros before submitting the write request */ if (!sblock_other) sblock_other = sblock_bad; if (scrub_write_sector_to_dev_replace(sblock_other, sector_num) != 0) { atomic64_inc( &fs_info->dev_replace.num_write_errors); success = 0; } } else if (sblock_other) { ret = scrub_repair_sector_from_good_copy(sblock_bad, sblock_other, sector_num, 0); if (0 == ret) sector_bad->io_error = 0; else success = 0; } } if (success && !sctx->is_dev_replace) { if (is_metadata || have_csum) { /* * need to verify the checksum now that all * sectors on disk are repaired (the write * request for data to be repaired is on its way). * Just be lazy and use scrub_recheck_block() * which re-reads the data before the checksum * is verified, but most likely the data comes out * of the page cache. */ scrub_recheck_block(fs_info, sblock_bad, 1); if (!sblock_bad->header_error && !sblock_bad->checksum_error && sblock_bad->no_io_error_seen) goto corrected_error; else goto did_not_correct_error; } else { corrected_error: spin_lock(&sctx->stat_lock); sctx->stat.corrected_errors++; sblock_to_check->data_corrected = 1; spin_unlock(&sctx->stat_lock); btrfs_err_rl_in_rcu(fs_info, "fixed up error at logical %llu on dev %s", logical, btrfs_dev_name(dev)); } } else { did_not_correct_error: spin_lock(&sctx->stat_lock); sctx->stat.uncorrectable_errors++; spin_unlock(&sctx->stat_lock); btrfs_err_rl_in_rcu(fs_info, "unable to fixup (regular) error at logical %llu on dev %s", logical, btrfs_dev_name(dev)); } out: for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS; mirror_index++) { struct scrub_block *sblock = sblocks_for_recheck[mirror_index]; struct scrub_recover *recover; int sector_index; /* Not allocated, continue checking the next mirror */ if (!sblock) continue; for (sector_index = 0; sector_index < sblock->sector_count; sector_index++) { /* * Here we just cleanup the recover, each sector will be * properly cleaned up by later scrub_block_put() */ recover = sblock->sectors[sector_index]->recover; if (recover) { scrub_put_recover(fs_info, recover); sblock->sectors[sector_index]->recover = NULL; } } scrub_block_put(sblock); } ret = unlock_full_stripe(fs_info, logical, full_stripe_locked); memalloc_nofs_restore(nofs_flag); if (ret < 0) return ret; return 0; } static inline int scrub_nr_raid_mirrors(struct btrfs_io_context *bioc) { if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID5) return 2; else if (bioc->map_type & BTRFS_BLOCK_GROUP_RAID6) return 3; else return (int)bioc->num_stripes; } static inline void scrub_stripe_index_and_offset(u64 logical, u64 map_type, u64 full_stripe_logical, int nstripes, int mirror, int *stripe_index, u64 *stripe_offset) { int i; if (map_type & BTRFS_BLOCK_GROUP_RAID56_MASK) { const int nr_data_stripes = (map_type & BTRFS_BLOCK_GROUP_RAID5) ? nstripes - 1 : nstripes - 2; /* RAID5/6 */ for (i = 0; i < nr_data_stripes; i++) { const u64 data_stripe_start = full_stripe_logical + (i * BTRFS_STRIPE_LEN); if (logical >= data_stripe_start && logical < data_stripe_start + BTRFS_STRIPE_LEN) break; } *stripe_index = i; *stripe_offset = (logical - full_stripe_logical) & BTRFS_STRIPE_LEN_MASK; } else { /* The other RAID type */ *stripe_index = mirror; *stripe_offset = 0; } } static int scrub_setup_recheck_block(struct scrub_block *original_sblock, struct scrub_block *sblocks_for_recheck[]) { struct scrub_ctx *sctx = original_sblock->sctx; struct btrfs_fs_info *fs_info = sctx->fs_info; u64 logical = original_sblock->logical; u64 length = original_sblock->sector_count << fs_info->sectorsize_bits; u64 generation = original_sblock->sectors[0]->generation; u64 flags = original_sblock->sectors[0]->flags; u64 have_csum = original_sblock->sectors[0]->have_csum; struct scrub_recover *recover; struct btrfs_io_context *bioc; u64 sublen; u64 mapped_length; u64 stripe_offset; int stripe_index; int sector_index = 0; int mirror_index; int nmirrors; int ret; while (length > 0) { sublen = min_t(u64, length, fs_info->sectorsize); mapped_length = sublen; bioc = NULL; /* * With a length of sectorsize, each returned stripe represents * one mirror */ btrfs_bio_counter_inc_blocked(fs_info); ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical, &mapped_length, &bioc); if (ret || !bioc || mapped_length < sublen) { btrfs_put_bioc(bioc); btrfs_bio_counter_dec(fs_info); return -EIO; } recover = kzalloc(sizeof(struct scrub_recover), GFP_KERNEL); if (!recover) { btrfs_put_bioc(bioc); btrfs_bio_counter_dec(fs_info); return -ENOMEM; } refcount_set(&recover->refs, 1); recover->bioc = bioc; recover->map_length = mapped_length; ASSERT(sector_index < SCRUB_MAX_SECTORS_PER_BLOCK); nmirrors = min(scrub_nr_raid_mirrors(bioc), BTRFS_MAX_MIRRORS); for (mirror_index = 0; mirror_index < nmirrors; mirror_index++) { struct scrub_block *sblock; struct scrub_sector *sector; sblock = sblocks_for_recheck[mirror_index]; sblock->sctx = sctx; sector = alloc_scrub_sector(sblock, logical); if (!sector) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); scrub_put_recover(fs_info, recover); return -ENOMEM; } sector->flags = flags; sector->generation = generation; sector->have_csum = have_csum; if (have_csum) memcpy(sector->csum, original_sblock->sectors[0]->csum, sctx->fs_info->csum_size); scrub_stripe_index_and_offset(logical, bioc->map_type, bioc->full_stripe_logical, bioc->num_stripes - bioc->replace_nr_stripes, mirror_index, &stripe_index, &stripe_offset); /* * We're at the first sector, also populate @sblock * physical and dev. */ if (sector_index == 0) { sblock->physical = bioc->stripes[stripe_index].physical + stripe_offset; sblock->dev = bioc->stripes[stripe_index].dev; sblock->physical_for_dev_replace = original_sblock->physical_for_dev_replace; } BUG_ON(sector_index >= original_sblock->sector_count); scrub_get_recover(recover); sector->recover = recover; } scrub_put_recover(fs_info, recover); length -= sublen; logical += sublen; sector_index++; } return 0; } static void scrub_bio_wait_endio(struct bio *bio) { complete(bio->bi_private); } static int scrub_submit_raid56_bio_wait(struct btrfs_fs_info *fs_info, struct bio *bio, struct scrub_sector *sector) { DECLARE_COMPLETION_ONSTACK(done); bio->bi_iter.bi_sector = (sector->offset + sector->sblock->logical) >> SECTOR_SHIFT; bio->bi_private = &done; bio->bi_end_io = scrub_bio_wait_endio; raid56_parity_recover(bio, sector->recover->bioc, sector->sblock->mirror_num); wait_for_completion_io(&done); return blk_status_to_errno(bio->bi_status); } static void scrub_recheck_block_on_raid56(struct btrfs_fs_info *fs_info, struct scrub_block *sblock) { struct scrub_sector *first_sector = sblock->sectors[0]; struct bio *bio; int i; /* All sectors in sblock belong to the same stripe on the same device. */ ASSERT(sblock->dev); if (!sblock->dev->bdev) goto out; bio = bio_alloc(sblock->dev->bdev, BIO_MAX_VECS, REQ_OP_READ, GFP_NOFS); for (i = 0; i < sblock->sector_count; i++) { struct scrub_sector *sector = sblock->sectors[i]; bio_add_scrub_sector(bio, sector, fs_info->sectorsize); } if (scrub_submit_raid56_bio_wait(fs_info, bio, first_sector)) { bio_put(bio); goto out; } bio_put(bio); scrub_recheck_block_checksum(sblock); return; out: for (i = 0; i < sblock->sector_count; i++) sblock->sectors[i]->io_error = 1; sblock->no_io_error_seen = 0; } /* * This function will check the on disk data for checksum errors, header errors * and read I/O errors. If any I/O errors happen, the exact sectors which are * errored are marked as being bad. The goal is to enable scrub to take those * sectors that are not errored from all the mirrors so that the sectors that * are errored in the just handled mirror can be repaired. */ static void scrub_recheck_block(struct btrfs_fs_info *fs_info, struct scrub_block *sblock, int retry_failed_mirror) { int i; sblock->no_io_error_seen = 1; /* short cut for raid56 */ if (!retry_failed_mirror && scrub_is_page_on_raid56(sblock->sectors[0])) return scrub_recheck_block_on_raid56(fs_info, sblock); for (i = 0; i < sblock->sector_count; i++) { struct scrub_sector *sector = sblock->sectors[i]; struct bio bio; struct bio_vec bvec; if (sblock->dev->bdev == NULL) { sector->io_error = 1; sblock->no_io_error_seen = 0; continue; } bio_init(&bio, sblock->dev->bdev, &bvec, 1, REQ_OP_READ); bio_add_scrub_sector(&bio, sector, fs_info->sectorsize); bio.bi_iter.bi_sector = (sblock->physical + sector->offset) >> SECTOR_SHIFT; btrfsic_check_bio(&bio); if (submit_bio_wait(&bio)) { sector->io_error = 1; sblock->no_io_error_seen = 0; } bio_uninit(&bio); } if (sblock->no_io_error_seen) scrub_recheck_block_checksum(sblock); } static inline int scrub_check_fsid(u8 fsid[], struct scrub_sector *sector) { struct btrfs_fs_devices *fs_devices = sector->sblock->dev->fs_devices; int ret; ret = memcmp(fsid, fs_devices->fsid, BTRFS_FSID_SIZE); return !ret; } static void scrub_recheck_block_checksum(struct scrub_block *sblock) { sblock->header_error = 0; sblock->checksum_error = 0; sblock->generation_error = 0; if (sblock->sectors[0]->flags & BTRFS_EXTENT_FLAG_DATA) scrub_checksum_data(sblock); else scrub_checksum_tree_block(sblock); } static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, struct scrub_block *sblock_good) { int i; int ret = 0; for (i = 0; i < sblock_bad->sector_count; i++) { int ret_sub; ret_sub = scrub_repair_sector_from_good_copy(sblock_bad, sblock_good, i, 1); if (ret_sub) ret = ret_sub; } return ret; } static int scrub_repair_sector_from_good_copy(struct scrub_block *sblock_bad, struct scrub_block *sblock_good, int sector_num, int force_write) { struct scrub_sector *sector_bad = sblock_bad->sectors[sector_num]; struct scrub_sector *sector_good = sblock_good->sectors[sector_num]; struct btrfs_fs_info *fs_info = sblock_bad->sctx->fs_info; const u32 sectorsize = fs_info->sectorsize; if (force_write || sblock_bad->header_error || sblock_bad->checksum_error || sector_bad->io_error) { struct bio bio; struct bio_vec bvec; int ret; if (!sblock_bad->dev->bdev) { btrfs_warn_rl(fs_info, "scrub_repair_page_from_good_copy(bdev == NULL) is unexpected"); return -EIO; } bio_init(&bio, sblock_bad->dev->bdev, &bvec, 1, REQ_OP_WRITE); bio.bi_iter.bi_sector = (sblock_bad->physical + sector_bad->offset) >> SECTOR_SHIFT; ret = bio_add_scrub_sector(&bio, sector_good, sectorsize); btrfsic_check_bio(&bio); ret = submit_bio_wait(&bio); bio_uninit(&bio); if (ret) { btrfs_dev_stat_inc_and_print(sblock_bad->dev, BTRFS_DEV_STAT_WRITE_ERRS); atomic64_inc(&fs_info->dev_replace.num_write_errors); return -EIO; } } return 0; } static void scrub_write_block_to_dev_replace(struct scrub_block *sblock) { struct btrfs_fs_info *fs_info = sblock->sctx->fs_info; int i; /* * This block is used for the check of the parity on the source device, * so the data needn't be written into the destination device. */ if (sblock->sparity) return; for (i = 0; i < sblock->sector_count; i++) { int ret; ret = scrub_write_sector_to_dev_replace(sblock, i); if (ret) atomic64_inc(&fs_info->dev_replace.num_write_errors); } } static int scrub_write_sector_to_dev_replace(struct scrub_block *sblock, int sector_num) { const u32 sectorsize = sblock->sctx->fs_info->sectorsize; struct scrub_sector *sector = sblock->sectors[sector_num]; if (sector->io_error) memset(scrub_sector_get_kaddr(sector), 0, sectorsize); return scrub_add_sector_to_wr_bio(sblock->sctx, sector); } static int fill_writer_pointer_gap(struct scrub_ctx *sctx, u64 physical) { int ret = 0; u64 length; if (!btrfs_is_zoned(sctx->fs_info)) return 0; if (!btrfs_dev_is_sequential(sctx->wr_tgtdev, physical)) return 0; if (sctx->write_pointer < physical) { length = physical - sctx->write_pointer; ret = btrfs_zoned_issue_zeroout(sctx->wr_tgtdev, sctx->write_pointer, length); if (!ret) sctx->write_pointer = physical; } return ret; } static void scrub_block_get(struct scrub_block *sblock) { refcount_inc(&sblock->refs); } static int scrub_add_sector_to_wr_bio(struct scrub_ctx *sctx, struct scrub_sector *sector) { struct scrub_block *sblock = sector->sblock; struct scrub_bio *sbio; int ret; const u32 sectorsize = sctx->fs_info->sectorsize; mutex_lock(&sctx->wr_lock); again: if (!sctx->wr_curr_bio) { sctx->wr_curr_bio = kzalloc(sizeof(*sctx->wr_curr_bio), GFP_KERNEL); if (!sctx->wr_curr_bio) { mutex_unlock(&sctx->wr_lock); return -ENOMEM; } sctx->wr_curr_bio->sctx = sctx; sctx->wr_curr_bio->sector_count = 0; } sbio = sctx->wr_curr_bio; if (sbio->sector_count == 0) { ret = fill_writer_pointer_gap(sctx, sector->offset + sblock->physical_for_dev_replace); if (ret) { mutex_unlock(&sctx->wr_lock); return ret; } sbio->physical = sblock->physical_for_dev_replace + sector->offset; sbio->logical = sblock->logical + sector->offset; sbio->dev = sctx->wr_tgtdev; if (!sbio->bio) { sbio->bio = bio_alloc(sbio->dev->bdev, sctx->sectors_per_bio, REQ_OP_WRITE, GFP_NOFS); } sbio->bio->bi_private = sbio; sbio->bio->bi_end_io = scrub_wr_bio_end_io; sbio->bio->bi_iter.bi_sector = sbio->physical >> 9; sbio->status = 0; } else if (sbio->physical + sbio->sector_count * sectorsize != sblock->physical_for_dev_replace + sector->offset || sbio->logical + sbio->sector_count * sectorsize != sblock->logical + sector->offset) { scrub_wr_submit(sctx); goto again; } ret = bio_add_scrub_sector(sbio->bio, sector, sectorsize); if (ret != sectorsize) { if (sbio->sector_count < 1) { bio_put(sbio->bio); sbio->bio = NULL; mutex_unlock(&sctx->wr_lock); return -EIO; } scrub_wr_submit(sctx); goto again; } sbio->sectors[sbio->sector_count] = sector; scrub_sector_get(sector); /* * Since ssector no longer holds a page, but uses sblock::pages, we * have to ensure the sblock had not been freed before our write bio * finished. */ scrub_block_get(sector->sblock); sbio->sector_count++; if (sbio->sector_count == sctx->sectors_per_bio) scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); return 0; } static void scrub_wr_submit(struct scrub_ctx *sctx) { struct scrub_bio *sbio; if (!sctx->wr_curr_bio) return; sbio = sctx->wr_curr_bio; sctx->wr_curr_bio = NULL; scrub_pending_bio_inc(sctx); /* process all writes in a single worker thread. Then the block layer * orders the requests before sending them to the driver which * doubled the write performance on spinning disks when measured * with Linux 3.5 */ btrfsic_check_bio(sbio->bio); submit_bio(sbio->bio); if (btrfs_is_zoned(sctx->fs_info)) sctx->write_pointer = sbio->physical + sbio->sector_count * sctx->fs_info->sectorsize; } static void scrub_wr_bio_end_io(struct bio *bio) { struct scrub_bio *sbio = bio->bi_private; struct btrfs_fs_info *fs_info = sbio->dev->fs_info; sbio->status = bio->bi_status; sbio->bio = bio; INIT_WORK(&sbio->work, scrub_wr_bio_end_io_worker); queue_work(fs_info->scrub_wr_completion_workers, &sbio->work); } static void scrub_wr_bio_end_io_worker(struct work_struct *work) { struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); struct scrub_ctx *sctx = sbio->sctx; int i; ASSERT(sbio->sector_count <= SCRUB_SECTORS_PER_BIO); if (sbio->status) { struct btrfs_dev_replace *dev_replace = &sbio->sctx->fs_info->dev_replace; for (i = 0; i < sbio->sector_count; i++) { struct scrub_sector *sector = sbio->sectors[i]; sector->io_error = 1; atomic64_inc(&dev_replace->num_write_errors); } } /* * In scrub_add_sector_to_wr_bio() we grab extra ref for sblock, now in * endio we should put the sblock. */ for (i = 0; i < sbio->sector_count; i++) { scrub_block_put(sbio->sectors[i]->sblock); scrub_sector_put(sbio->sectors[i]); } bio_put(sbio->bio); kfree(sbio); scrub_pending_bio_dec(sctx); } static int scrub_checksum(struct scrub_block *sblock) { u64 flags; int ret; /* * No need to initialize these stats currently, * because this function only use return value * instead of these stats value. * * Todo: * always use stats */ sblock->header_error = 0; sblock->generation_error = 0; sblock->checksum_error = 0; WARN_ON(sblock->sector_count < 1); flags = sblock->sectors[0]->flags; ret = 0; if (flags & BTRFS_EXTENT_FLAG_DATA) ret = scrub_checksum_data(sblock); else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) ret = scrub_checksum_tree_block(sblock); else if (flags & BTRFS_EXTENT_FLAG_SUPER) ret = scrub_checksum_super(sblock); else WARN_ON(1); if (ret) scrub_handle_errored_block(sblock); return ret; } static int scrub_checksum_data(struct scrub_block *sblock) { struct scrub_ctx *sctx = sblock->sctx; struct btrfs_fs_info *fs_info = sctx->fs_info; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); u8 csum[BTRFS_CSUM_SIZE]; struct scrub_sector *sector; char *kaddr; BUG_ON(sblock->sector_count < 1); sector = sblock->sectors[0]; if (!sector->have_csum) return 0; kaddr = scrub_sector_get_kaddr(sector); shash->tfm = fs_info->csum_shash; crypto_shash_init(shash); crypto_shash_digest(shash, kaddr, fs_info->sectorsize, csum); if (memcmp(csum, sector->csum, fs_info->csum_size)) sblock->checksum_error = 1; return sblock->checksum_error; } static struct page *scrub_stripe_get_page(struct scrub_stripe *stripe, int sector_nr) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; int page_index = (sector_nr << fs_info->sectorsize_bits) >> PAGE_SHIFT; return stripe->pages[page_index]; } static unsigned int scrub_stripe_get_page_offset(struct scrub_stripe *stripe, int sector_nr) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; return offset_in_page(sector_nr << fs_info->sectorsize_bits); } static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; const u64 logical = stripe->logical + (sector_nr << fs_info->sectorsize_bits); const struct page *first_page = scrub_stripe_get_page(stripe, sector_nr); const unsigned int first_off = scrub_stripe_get_page_offset(stripe, sector_nr); SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); u8 on_disk_csum[BTRFS_CSUM_SIZE]; u8 calculated_csum[BTRFS_CSUM_SIZE]; struct btrfs_header *header; /* * Here we don't have a good way to attach the pages (and subpages) * to a dummy extent buffer, thus we have to directly grab the members * from pages. */ header = (struct btrfs_header *)(page_address(first_page) + first_off); memcpy(on_disk_csum, header->csum, fs_info->csum_size); if (logical != btrfs_stack_header_bytenr(header)) { bitmap_set(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree); bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad bytenr, has %llu want %llu", logical, stripe->mirror_num, btrfs_stack_header_bytenr(header), logical); return; } if (memcmp(header->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE) != 0) { bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad fsid, has %pU want %pU", logical, stripe->mirror_num, header->fsid, fs_info->fs_devices->fsid); return; } if (memcmp(header->chunk_tree_uuid, fs_info->chunk_tree_uuid, BTRFS_UUID_SIZE) != 0) { bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad chunk tree uuid, has %pU want %pU", logical, stripe->mirror_num, header->chunk_tree_uuid, fs_info->chunk_tree_uuid); return; } /* Now check tree block csum. */ shash->tfm = fs_info->csum_shash; crypto_shash_init(shash); crypto_shash_update(shash, page_address(first_page) + first_off + BTRFS_CSUM_SIZE, fs_info->sectorsize - BTRFS_CSUM_SIZE); for (int i = sector_nr + 1; i < sector_nr + sectors_per_tree; i++) { struct page *page = scrub_stripe_get_page(stripe, i); unsigned int page_off = scrub_stripe_get_page_offset(stripe, i); crypto_shash_update(shash, page_address(page) + page_off, fs_info->sectorsize); } crypto_shash_final(shash, calculated_csum); if (memcmp(calculated_csum, on_disk_csum, fs_info->csum_size) != 0) { bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad csum, has " CSUM_FMT " want " CSUM_FMT, logical, stripe->mirror_num, CSUM_FMT_VALUE(fs_info->csum_size, on_disk_csum), CSUM_FMT_VALUE(fs_info->csum_size, calculated_csum)); return; } if (stripe->sectors[sector_nr].generation != btrfs_stack_header_generation(header)) { bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad generation, has %llu want %llu", logical, stripe->mirror_num, btrfs_stack_header_generation(header), stripe->sectors[sector_nr].generation); return; } bitmap_clear(&stripe->error_bitmap, sector_nr, sectors_per_tree); bitmap_clear(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree); bitmap_clear(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); } static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct scrub_sector_verification *sector = &stripe->sectors[sector_nr]; const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; struct page *page = scrub_stripe_get_page(stripe, sector_nr); unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); u8 csum_buf[BTRFS_CSUM_SIZE]; int ret; ASSERT(sector_nr >= 0 && sector_nr < stripe->nr_sectors); /* Sector not utilized, skip it. */ if (!test_bit(sector_nr, &stripe->extent_sector_bitmap)) return; /* IO error, no need to check. */ if (test_bit(sector_nr, &stripe->io_error_bitmap)) return; /* Metadata, verify the full tree block. */ if (sector->is_metadata) { /* * Check if the tree block crosses the stripe boudary. If * crossed the boundary, we cannot verify it but only give a * warning. * * This can only happen on a very old filesystem where chunks * are not ensured to be stripe aligned. */ if (unlikely(sector_nr + sectors_per_tree > stripe->nr_sectors)) { btrfs_warn_rl(fs_info, "tree block at %llu crosses stripe boundary %llu", stripe->logical + (sector_nr << fs_info->sectorsize_bits), stripe->logical); return; } scrub_verify_one_metadata(stripe, sector_nr); return; } /* * Data is easier, we just verify the data csum (if we have it). For * cases without csum, we have no other choice but to trust it. */ if (!sector->csum) { clear_bit(sector_nr, &stripe->error_bitmap); return; } ret = btrfs_check_sector_csum(fs_info, page, pgoff, csum_buf, sector->csum); if (ret < 0) { set_bit(sector_nr, &stripe->csum_error_bitmap); set_bit(sector_nr, &stripe->error_bitmap); } else { clear_bit(sector_nr, &stripe->csum_error_bitmap); clear_bit(sector_nr, &stripe->error_bitmap); } } /* Verify specified sectors of a stripe. */ static void scrub_verify_one_stripe(struct scrub_stripe *stripe, unsigned long bitmap) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; int sector_nr; for_each_set_bit(sector_nr, &bitmap, stripe->nr_sectors) { scrub_verify_one_sector(stripe, sector_nr); if (stripe->sectors[sector_nr].is_metadata) sector_nr += sectors_per_tree - 1; } } static int calc_sector_number(struct scrub_stripe *stripe, struct bio_vec *first_bvec) { int i; for (i = 0; i < stripe->nr_sectors; i++) { if (scrub_stripe_get_page(stripe, i) == first_bvec->bv_page && scrub_stripe_get_page_offset(stripe, i) == first_bvec->bv_offset) break; } ASSERT(i < stripe->nr_sectors); return i; } /* * Repair read is different to the regular read: * * - Only reads the failed sectors * - May have extra blocksize limits */ static void scrub_repair_read_endio(struct btrfs_bio *bbio) { struct scrub_stripe *stripe = bbio->private; struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct bio_vec *bvec; int sector_nr = calc_sector_number(stripe, bio_first_bvec_all(&bbio->bio)); u32 bio_size = 0; int i; ASSERT(sector_nr < stripe->nr_sectors); bio_for_each_bvec_all(bvec, &bbio->bio, i) bio_size += bvec->bv_len; if (bbio->bio.bi_status) { bitmap_set(&stripe->io_error_bitmap, sector_nr, bio_size >> fs_info->sectorsize_bits); bitmap_set(&stripe->error_bitmap, sector_nr, bio_size >> fs_info->sectorsize_bits); } else { bitmap_clear(&stripe->io_error_bitmap, sector_nr, bio_size >> fs_info->sectorsize_bits); } bio_put(&bbio->bio); if (atomic_dec_and_test(&stripe->pending_io)) wake_up(&stripe->io_wait); } static int calc_next_mirror(int mirror, int num_copies) { ASSERT(mirror <= num_copies); return (mirror + 1 > num_copies) ? 1 : mirror + 1; } static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, int mirror, int blocksize, bool wait) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct btrfs_bio *bbio = NULL; const unsigned long old_error_bitmap = stripe->error_bitmap; int i; ASSERT(stripe->mirror_num >= 1); ASSERT(atomic_read(&stripe->pending_io) == 0); for_each_set_bit(i, &old_error_bitmap, stripe->nr_sectors) { struct page *page; int pgoff; int ret; page = scrub_stripe_get_page(stripe, i); pgoff = scrub_stripe_get_page_offset(stripe, i); /* The current sector cannot be merged, submit the bio. */ if (bbio && ((i > 0 && !test_bit(i - 1, &stripe->error_bitmap)) || bbio->bio.bi_iter.bi_size >= blocksize)) { ASSERT(bbio->bio.bi_iter.bi_size); atomic_inc(&stripe->pending_io); btrfs_submit_bio(bbio, mirror); if (wait) wait_scrub_stripe_io(stripe); bbio = NULL; } if (!bbio) { bbio = btrfs_bio_alloc(stripe->nr_sectors, REQ_OP_READ, fs_info, scrub_repair_read_endio, stripe); bbio->bio.bi_iter.bi_sector = (stripe->logical + (i << fs_info->sectorsize_bits)) >> SECTOR_SHIFT; } ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); ASSERT(ret == fs_info->sectorsize); } if (bbio) { ASSERT(bbio->bio.bi_iter.bi_size); atomic_inc(&stripe->pending_io); btrfs_submit_bio(bbio, mirror); if (wait) wait_scrub_stripe_io(stripe); } } static void scrub_stripe_report_errors(struct scrub_ctx *sctx, struct scrub_stripe *stripe) { static DEFINE_RATELIMIT_STATE(rs, DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); struct btrfs_fs_info *fs_info = sctx->fs_info; struct btrfs_device *dev = NULL; u64 physical = 0; int nr_data_sectors = 0; int nr_meta_sectors = 0; int nr_nodatacsum_sectors = 0; int nr_repaired_sectors = 0; int sector_nr; /* * Init needed infos for error reporting. * * Although our scrub_stripe infrastucture is mostly based on btrfs_submit_bio() * thus no need for dev/physical, error reporting still needs dev and physical. */ if (!bitmap_empty(&stripe->init_error_bitmap, stripe->nr_sectors)) { u64 mapped_len = fs_info->sectorsize; struct btrfs_io_context *bioc = NULL; int stripe_index = stripe->mirror_num - 1; int ret; /* For scrub, our mirror_num should always start at 1. */ ASSERT(stripe->mirror_num >= 1); ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, stripe->logical, &mapped_len, &bioc); /* * If we failed, dev will be NULL, and later detailed reports * will just be skipped. */ if (ret < 0) goto skip; physical = bioc->stripes[stripe_index].physical; dev = bioc->stripes[stripe_index].dev; btrfs_put_bioc(bioc); } skip: for_each_set_bit(sector_nr, &stripe->extent_sector_bitmap, stripe->nr_sectors) { bool repaired = false; if (stripe->sectors[sector_nr].is_metadata) { nr_meta_sectors++; } else { nr_data_sectors++; if (!stripe->sectors[sector_nr].csum) nr_nodatacsum_sectors++; } if (test_bit(sector_nr, &stripe->init_error_bitmap) && !test_bit(sector_nr, &stripe->error_bitmap)) { nr_repaired_sectors++; repaired = true; } /* Good sector from the beginning, nothing need to be done. */ if (!test_bit(sector_nr, &stripe->init_error_bitmap)) continue; /* * Report error for the corrupted sectors. If repaired, just * output the message of repaired message. */ if (repaired) { if (dev) { btrfs_err_rl_in_rcu(fs_info, "fixed up error at logical %llu on dev %s physical %llu", stripe->logical, btrfs_dev_name(dev), physical); } else { btrfs_err_rl_in_rcu(fs_info, "fixed up error at logical %llu on mirror %u", stripe->logical, stripe->mirror_num); } continue; } /* The remaining are all for unrepaired. */ if (dev) { btrfs_err_rl_in_rcu(fs_info, "unable to fixup (regular) error at logical %llu on dev %s physical %llu", stripe->logical, btrfs_dev_name(dev), physical); } else { btrfs_err_rl_in_rcu(fs_info, "unable to fixup (regular) error at logical %llu on mirror %u", stripe->logical, stripe->mirror_num); } if (test_bit(sector_nr, &stripe->io_error_bitmap)) if (__ratelimit(&rs) && dev) scrub_print_common_warning("i/o error", dev, false, stripe->logical, physical); if (test_bit(sector_nr, &stripe->csum_error_bitmap)) if (__ratelimit(&rs) && dev) scrub_print_common_warning("checksum error", dev, false, stripe->logical, physical); if (test_bit(sector_nr, &stripe->meta_error_bitmap)) if (__ratelimit(&rs) && dev) scrub_print_common_warning("header error", dev, false, stripe->logical, physical); } spin_lock(&sctx->stat_lock); sctx->stat.data_extents_scrubbed += stripe->nr_data_extents; sctx->stat.tree_extents_scrubbed += stripe->nr_meta_extents; sctx->stat.data_bytes_scrubbed += nr_data_sectors << fs_info->sectorsize_bits; sctx->stat.tree_bytes_scrubbed += nr_meta_sectors << fs_info->sectorsize_bits; sctx->stat.no_csum += nr_nodatacsum_sectors; sctx->stat.read_errors += bitmap_weight(&stripe->io_error_bitmap, stripe->nr_sectors); sctx->stat.csum_errors += bitmap_weight(&stripe->csum_error_bitmap, stripe->nr_sectors); sctx->stat.verify_errors += bitmap_weight(&stripe->meta_error_bitmap, stripe->nr_sectors); sctx->stat.uncorrectable_errors += bitmap_weight(&stripe->error_bitmap, stripe->nr_sectors); sctx->stat.corrected_errors += nr_repaired_sectors; spin_unlock(&sctx->stat_lock); } /* * The main entrance for all read related scrub work, including: * * - Wait for the initial read to finish * - Verify and locate any bad sectors * - Go through the remaining mirrors and try to read as large blocksize as * possible * - Go through all mirrors (including the failed mirror) sector-by-sector * * Writeback does not happen here, it needs extra synchronization. */ static void scrub_stripe_read_repair_worker(struct work_struct *work) { struct scrub_stripe *stripe = container_of(work, struct scrub_stripe, work); struct btrfs_fs_info *fs_info = stripe->bg->fs_info; int num_copies = btrfs_num_copies(fs_info, stripe->bg->start, stripe->bg->length); int mirror; int i; ASSERT(stripe->mirror_num > 0); wait_scrub_stripe_io(stripe); scrub_verify_one_stripe(stripe, stripe->extent_sector_bitmap); /* Save the initial failed bitmap for later repair and report usage. */ stripe->init_error_bitmap = stripe->error_bitmap; if (bitmap_empty(&stripe->init_error_bitmap, stripe->nr_sectors)) goto out; /* * Try all remaining mirrors. * * Here we still try to read as large block as possible, as this is * faster and we have extra safety nets to rely on. */ for (mirror = calc_next_mirror(stripe->mirror_num, num_copies); mirror != stripe->mirror_num; mirror = calc_next_mirror(mirror, num_copies)) { const unsigned long old_error_bitmap = stripe->error_bitmap; scrub_stripe_submit_repair_read(stripe, mirror, BTRFS_STRIPE_LEN, false); wait_scrub_stripe_io(stripe); scrub_verify_one_stripe(stripe, old_error_bitmap); if (bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors)) goto out; } /* * Last safety net, try re-checking all mirrors, including the failed * one, sector-by-sector. * * As if one sector failed the drive's internal csum, the whole read * containing the offending sector would be marked as error. * Thus here we do sector-by-sector read. * * This can be slow, thus we only try it as the last resort. */ for (i = 0, mirror = stripe->mirror_num; i < num_copies; i++, mirror = calc_next_mirror(mirror, num_copies)) { const unsigned long old_error_bitmap = stripe->error_bitmap; scrub_stripe_submit_repair_read(stripe, mirror, fs_info->sectorsize, true); wait_scrub_stripe_io(stripe); scrub_verify_one_stripe(stripe, old_error_bitmap); if (bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors)) goto out; } out: scrub_stripe_report_errors(stripe->sctx, stripe); set_bit(SCRUB_STRIPE_FLAG_REPAIR_DONE, &stripe->state); wake_up(&stripe->repair_wait); } static void scrub_read_endio(struct btrfs_bio *bbio) { struct scrub_stripe *stripe = bbio->private; if (bbio->bio.bi_status) { bitmap_set(&stripe->io_error_bitmap, 0, stripe->nr_sectors); bitmap_set(&stripe->error_bitmap, 0, stripe->nr_sectors); } else { bitmap_clear(&stripe->io_error_bitmap, 0, stripe->nr_sectors); } bio_put(&bbio->bio); if (atomic_dec_and_test(&stripe->pending_io)) { wake_up(&stripe->io_wait); INIT_WORK(&stripe->work, scrub_stripe_read_repair_worker); queue_work(stripe->bg->fs_info->scrub_workers, &stripe->work); } } static void scrub_write_endio(struct btrfs_bio *bbio) { struct scrub_stripe *stripe = bbio->private; struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct bio_vec *bvec; int sector_nr = calc_sector_number(stripe, bio_first_bvec_all(&bbio->bio)); u32 bio_size = 0; int i; bio_for_each_bvec_all(bvec, &bbio->bio, i) bio_size += bvec->bv_len; if (bbio->bio.bi_status) { unsigned long flags; spin_lock_irqsave(&stripe->write_error_lock, flags); bitmap_set(&stripe->write_error_bitmap, sector_nr, bio_size >> fs_info->sectorsize_bits); spin_unlock_irqrestore(&stripe->write_error_lock, flags); } bio_put(&bbio->bio); if (atomic_dec_and_test(&stripe->pending_io)) wake_up(&stripe->io_wait); } /* * Submit the write bio(s) for the sectors specified by @write_bitmap. * * Here we utilize btrfs_submit_repair_write(), which has some extra benefits: * * - Only needs logical bytenr and mirror_num * Just like the scrub read path * * - Would only result in writes to the specified mirror * Unlike the regular writeback path, which would write back to all stripes * * - Handle dev-replace and read-repair writeback differently */ static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *stripe, unsigned long write_bitmap, bool dev_replace) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct btrfs_bio *bbio = NULL; const bool zoned = btrfs_is_zoned(fs_info); int sector_nr; for_each_set_bit(sector_nr, &write_bitmap, stripe->nr_sectors) { struct page *page = scrub_stripe_get_page(stripe, sector_nr); unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); int ret; /* We should only writeback sectors covered by an extent. */ ASSERT(test_bit(sector_nr, &stripe->extent_sector_bitmap)); /* Cannot merge with previous sector, submit the current one. */ if (bbio && sector_nr && !test_bit(sector_nr - 1, &write_bitmap)) { fill_writer_pointer_gap(sctx, stripe->physical + (sector_nr << fs_info->sectorsize_bits)); atomic_inc(&stripe->pending_io); btrfs_submit_repair_write(bbio, stripe->mirror_num, dev_replace); /* For zoned writeback, queue depth must be 1. */ if (zoned) wait_scrub_stripe_io(stripe); bbio = NULL; } if (!bbio) { bbio = btrfs_bio_alloc(stripe->nr_sectors, REQ_OP_WRITE, fs_info, scrub_write_endio, stripe); bbio->bio.bi_iter.bi_sector = (stripe->logical + (sector_nr << fs_info->sectorsize_bits)) >> SECTOR_SHIFT; } ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); ASSERT(ret == fs_info->sectorsize); } if (bbio) { fill_writer_pointer_gap(sctx, bbio->bio.bi_iter.bi_sector << SECTOR_SHIFT); atomic_inc(&stripe->pending_io); btrfs_submit_repair_write(bbio, stripe->mirror_num, dev_replace); if (zoned) wait_scrub_stripe_io(stripe); } } static int scrub_checksum_tree_block(struct scrub_block *sblock) { struct scrub_ctx *sctx = sblock->sctx; struct btrfs_header *h; struct btrfs_fs_info *fs_info = sctx->fs_info; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); u8 calculated_csum[BTRFS_CSUM_SIZE]; u8 on_disk_csum[BTRFS_CSUM_SIZE]; /* * This is done in sectorsize steps even for metadata as there's a * constraint for nodesize to be aligned to sectorsize. This will need * to change so we don't misuse data and metadata units like that. */ const u32 sectorsize = sctx->fs_info->sectorsize; const int num_sectors = fs_info->nodesize >> fs_info->sectorsize_bits; int i; struct scrub_sector *sector; char *kaddr; BUG_ON(sblock->sector_count < 1); /* Each member in sectors is just one sector */ ASSERT(sblock->sector_count == num_sectors); sector = sblock->sectors[0]; kaddr = scrub_sector_get_kaddr(sector); h = (struct btrfs_header *)kaddr; memcpy(on_disk_csum, h->csum, sctx->fs_info->csum_size); /* * we don't use the getter functions here, as we * a) don't have an extent buffer and * b) the page is already kmapped */ if (sblock->logical != btrfs_stack_header_bytenr(h)) { sblock->header_error = 1; btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad bytenr, has %llu want %llu", sblock->logical, sblock->mirror_num, btrfs_stack_header_bytenr(h), sblock->logical); goto out; } if (!scrub_check_fsid(h->fsid, sector)) { sblock->header_error = 1; btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad fsid, has %pU want %pU", sblock->logical, sblock->mirror_num, h->fsid, sblock->dev->fs_devices->fsid); goto out; } if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, BTRFS_UUID_SIZE)) { sblock->header_error = 1; btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad chunk tree uuid, has %pU want %pU", sblock->logical, sblock->mirror_num, h->chunk_tree_uuid, fs_info->chunk_tree_uuid); goto out; } shash->tfm = fs_info->csum_shash; crypto_shash_init(shash); crypto_shash_update(shash, kaddr + BTRFS_CSUM_SIZE, sectorsize - BTRFS_CSUM_SIZE); for (i = 1; i < num_sectors; i++) { kaddr = scrub_sector_get_kaddr(sblock->sectors[i]); crypto_shash_update(shash, kaddr, sectorsize); } crypto_shash_final(shash, calculated_csum); if (memcmp(calculated_csum, on_disk_csum, sctx->fs_info->csum_size)) { sblock->checksum_error = 1; btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad csum, has " CSUM_FMT " want " CSUM_FMT, sblock->logical, sblock->mirror_num, CSUM_FMT_VALUE(fs_info->csum_size, on_disk_csum), CSUM_FMT_VALUE(fs_info->csum_size, calculated_csum)); goto out; } if (sector->generation != btrfs_stack_header_generation(h)) { sblock->header_error = 1; sblock->generation_error = 1; btrfs_warn_rl(fs_info, "tree block %llu mirror %u has bad generation, has %llu want %llu", sblock->logical, sblock->mirror_num, btrfs_stack_header_generation(h), sector->generation); } out: return sblock->header_error || sblock->checksum_error; } static int scrub_checksum_super(struct scrub_block *sblock) { struct btrfs_super_block *s; struct scrub_ctx *sctx = sblock->sctx; struct btrfs_fs_info *fs_info = sctx->fs_info; SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); u8 calculated_csum[BTRFS_CSUM_SIZE]; struct scrub_sector *sector; char *kaddr; int fail_gen = 0; int fail_cor = 0; BUG_ON(sblock->sector_count < 1); sector = sblock->sectors[0]; kaddr = scrub_sector_get_kaddr(sector); s = (struct btrfs_super_block *)kaddr; if (sblock->logical != btrfs_super_bytenr(s)) ++fail_cor; if (sector->generation != btrfs_super_generation(s)) ++fail_gen; if (!scrub_check_fsid(s->fsid, sector)) ++fail_cor; shash->tfm = fs_info->csum_shash; crypto_shash_init(shash); crypto_shash_digest(shash, kaddr + BTRFS_CSUM_SIZE, BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, calculated_csum); if (memcmp(calculated_csum, s->csum, sctx->fs_info->csum_size)) ++fail_cor; return fail_cor + fail_gen; } static void scrub_block_put(struct scrub_block *sblock) { if (refcount_dec_and_test(&sblock->refs)) { int i; if (sblock->sparity) scrub_parity_put(sblock->sparity); for (i = 0; i < sblock->sector_count; i++) scrub_sector_put(sblock->sectors[i]); for (i = 0; i < DIV_ROUND_UP(sblock->len, PAGE_SIZE); i++) { if (sblock->pages[i]) { detach_scrub_page_private(sblock->pages[i]); __free_page(sblock->pages[i]); } } kfree(sblock); } } static void scrub_sector_get(struct scrub_sector *sector) { atomic_inc(§or->refs); } static void scrub_sector_put(struct scrub_sector *sector) { if (atomic_dec_and_test(§or->refs)) kfree(sector); } static void scrub_throttle_dev_io(struct scrub_ctx *sctx, struct btrfs_device *device, unsigned int bio_size) { const int time_slice = 1000; s64 delta; ktime_t now; u32 div; u64 bwlimit; bwlimit = READ_ONCE(device->scrub_speed_max); if (bwlimit == 0) return; /* * Slice is divided into intervals when the IO is submitted, adjust by * bwlimit and maximum of 64 intervals. */ div = max_t(u32, 1, (u32)(bwlimit / (16 * 1024 * 1024))); div = min_t(u32, 64, div); /* Start new epoch, set deadline */ now = ktime_get(); if (sctx->throttle_deadline == 0) { sctx->throttle_deadline = ktime_add_ms(now, time_slice / div); sctx->throttle_sent = 0; } /* Still in the time to send? */ if (ktime_before(now, sctx->throttle_deadline)) { /* If current bio is within the limit, send it */ sctx->throttle_sent += bio_size; if (sctx->throttle_sent <= div_u64(bwlimit, div)) return; /* We're over the limit, sleep until the rest of the slice */ delta = ktime_ms_delta(sctx->throttle_deadline, now); } else { /* New request after deadline, start new epoch */ delta = 0; } if (delta) { long timeout; timeout = div_u64(delta * HZ, 1000); schedule_timeout_interruptible(timeout); } /* Next call will start the deadline period */ sctx->throttle_deadline = 0; } /* * Throttling of IO submission, bandwidth-limit based, the timeslice is 1 * second. Limit can be set via /sys/fs/UUID/devinfo/devid/scrub_speed_max. */ static void scrub_throttle(struct scrub_ctx *sctx) { struct scrub_bio *sbio = sctx->bios[sctx->curr]; scrub_throttle_dev_io(sctx, sbio->dev, sbio->bio->bi_iter.bi_size); } static void scrub_submit(struct scrub_ctx *sctx) { struct scrub_bio *sbio; if (sctx->curr == -1) return; scrub_throttle(sctx); sbio = sctx->bios[sctx->curr]; sctx->curr = -1; scrub_pending_bio_inc(sctx); btrfsic_check_bio(sbio->bio); submit_bio(sbio->bio); } static int scrub_add_sector_to_rd_bio(struct scrub_ctx *sctx, struct scrub_sector *sector) { struct scrub_block *sblock = sector->sblock; struct scrub_bio *sbio; const u32 sectorsize = sctx->fs_info->sectorsize; int ret; again: /* * grab a fresh bio or wait for one to become available */ while (sctx->curr == -1) { spin_lock(&sctx->list_lock); sctx->curr = sctx->first_free; if (sctx->curr != -1) { sctx->first_free = sctx->bios[sctx->curr]->next_free; sctx->bios[sctx->curr]->next_free = -1; sctx->bios[sctx->curr]->sector_count = 0; spin_unlock(&sctx->list_lock); } else { spin_unlock(&sctx->list_lock); wait_event(sctx->list_wait, sctx->first_free != -1); } } sbio = sctx->bios[sctx->curr]; if (sbio->sector_count == 0) { sbio->physical = sblock->physical + sector->offset; sbio->logical = sblock->logical + sector->offset; sbio->dev = sblock->dev; if (!sbio->bio) { sbio->bio = bio_alloc(sbio->dev->bdev, sctx->sectors_per_bio, REQ_OP_READ, GFP_NOFS); } sbio->bio->bi_private = sbio; sbio->bio->bi_end_io = scrub_bio_end_io; sbio->bio->bi_iter.bi_sector = sbio->physical >> 9; sbio->status = 0; } else if (sbio->physical + sbio->sector_count * sectorsize != sblock->physical + sector->offset || sbio->logical + sbio->sector_count * sectorsize != sblock->logical + sector->offset || sbio->dev != sblock->dev) { scrub_submit(sctx); goto again; } sbio->sectors[sbio->sector_count] = sector; ret = bio_add_scrub_sector(sbio->bio, sector, sectorsize); if (ret != sectorsize) { if (sbio->sector_count < 1) { bio_put(sbio->bio); sbio->bio = NULL; return -EIO; } scrub_submit(sctx); goto again; } scrub_block_get(sblock); /* one for the page added to the bio */ atomic_inc(&sblock->outstanding_sectors); sbio->sector_count++; if (sbio->sector_count == sctx->sectors_per_bio) scrub_submit(sctx); return 0; } static void scrub_bio_end_io(struct bio *bio) { struct scrub_bio *sbio = bio->bi_private; struct btrfs_fs_info *fs_info = sbio->dev->fs_info; sbio->status = bio->bi_status; sbio->bio = bio; queue_work(fs_info->scrub_workers, &sbio->work); } static void scrub_bio_end_io_worker(struct work_struct *work) { struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); struct scrub_ctx *sctx = sbio->sctx; int i; ASSERT(sbio->sector_count <= SCRUB_SECTORS_PER_BIO); if (sbio->status) { for (i = 0; i < sbio->sector_count; i++) { struct scrub_sector *sector = sbio->sectors[i]; sector->io_error = 1; sector->sblock->no_io_error_seen = 0; } } /* Now complete the scrub_block items that have all pages completed */ for (i = 0; i < sbio->sector_count; i++) { struct scrub_sector *sector = sbio->sectors[i]; struct scrub_block *sblock = sector->sblock; if (atomic_dec_and_test(&sblock->outstanding_sectors)) scrub_block_complete(sblock); scrub_block_put(sblock); } bio_put(sbio->bio); sbio->bio = NULL; spin_lock(&sctx->list_lock); sbio->next_free = sctx->first_free; sctx->first_free = sbio->index; spin_unlock(&sctx->list_lock); if (sctx->is_dev_replace && sctx->flush_all_writes) { mutex_lock(&sctx->wr_lock); scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); } scrub_pending_bio_dec(sctx); } static inline void __scrub_mark_bitmap(struct scrub_parity *sparity, unsigned long *bitmap, u64 start, u32 len) { u64 offset; u32 nsectors; u32 sectorsize_bits = sparity->sctx->fs_info->sectorsize_bits; if (len >= sparity->stripe_len) { bitmap_set(bitmap, 0, sparity->nsectors); return; } start -= sparity->logic_start; start = div64_u64_rem(start, sparity->stripe_len, &offset); offset = offset >> sectorsize_bits; nsectors = len >> sectorsize_bits; if (offset + nsectors <= sparity->nsectors) { bitmap_set(bitmap, offset, nsectors); return; } bitmap_set(bitmap, offset, sparity->nsectors - offset); bitmap_set(bitmap, 0, nsectors - (sparity->nsectors - offset)); } static inline void scrub_parity_mark_sectors_error(struct scrub_parity *sparity, u64 start, u32 len) { __scrub_mark_bitmap(sparity, &sparity->ebitmap, start, len); } static inline void scrub_parity_mark_sectors_data(struct scrub_parity *sparity, u64 start, u32 len) { __scrub_mark_bitmap(sparity, &sparity->dbitmap, start, len); } static void scrub_block_complete(struct scrub_block *sblock) { int corrupted = 0; if (!sblock->no_io_error_seen) { corrupted = 1; scrub_handle_errored_block(sblock); } else { /* * if has checksum error, write via repair mechanism in * dev replace case, otherwise write here in dev replace * case. */ corrupted = scrub_checksum(sblock); if (!corrupted && sblock->sctx->is_dev_replace) scrub_write_block_to_dev_replace(sblock); } if (sblock->sparity && corrupted && !sblock->data_corrected) { u64 start = sblock->logical; u64 end = sblock->logical + sblock->sectors[sblock->sector_count - 1]->offset + sblock->sctx->fs_info->sectorsize; ASSERT(end - start <= U32_MAX); scrub_parity_mark_sectors_error(sblock->sparity, start, end - start); } } static void drop_csum_range(struct scrub_ctx *sctx, struct btrfs_ordered_sum *sum) { sctx->stat.csum_discards += sum->len >> sctx->fs_info->sectorsize_bits; list_del(&sum->list); kfree(sum); } /* * Find the desired csum for range [logical, logical + sectorsize), and store * the csum into @csum. * * The search source is sctx->csum_list, which is a pre-populated list * storing bytenr ordered csum ranges. We're responsible to cleanup any range * that is before @logical. * * Return 0 if there is no csum for the range. * Return 1 if there is csum for the range and copied to @csum. */ static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u8 *csum) { bool found = false; while (!list_empty(&sctx->csum_list)) { struct btrfs_ordered_sum *sum = NULL; unsigned long index; unsigned long num_sectors; sum = list_first_entry(&sctx->csum_list, struct btrfs_ordered_sum, list); /* The current csum range is beyond our range, no csum found */ if (sum->bytenr > logical) break; /* * The current sum is before our bytenr, since scrub is always * done in bytenr order, the csum will never be used anymore, * clean it up so that later calls won't bother with the range, * and continue search the next range. */ if (sum->bytenr + sum->len <= logical) { drop_csum_range(sctx, sum); continue; } /* Now the csum range covers our bytenr, copy the csum */ found = true; index = (logical - sum->bytenr) >> sctx->fs_info->sectorsize_bits; num_sectors = sum->len >> sctx->fs_info->sectorsize_bits; memcpy(csum, sum->sums + index * sctx->fs_info->csum_size, sctx->fs_info->csum_size); /* Cleanup the range if we're at the end of the csum range */ if (index == num_sectors - 1) drop_csum_range(sctx, sum); break; } if (!found) return 0; return 1; } static int scrub_sectors_for_parity(struct scrub_parity *sparity, u64 logical, u32 len, u64 physical, struct btrfs_device *dev, u64 flags, u64 gen, int mirror_num, u8 *csum) { struct scrub_ctx *sctx = sparity->sctx; struct scrub_block *sblock; const u32 sectorsize = sctx->fs_info->sectorsize; int index; ASSERT(IS_ALIGNED(len, sectorsize)); sblock = alloc_scrub_block(sctx, dev, logical, physical, physical, mirror_num); if (!sblock) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); return -ENOMEM; } sblock->sparity = sparity; scrub_parity_get(sparity); for (index = 0; len > 0; index++) { struct scrub_sector *sector; sector = alloc_scrub_sector(sblock, logical); if (!sector) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); scrub_block_put(sblock); return -ENOMEM; } sblock->sectors[index] = sector; /* For scrub parity */ scrub_sector_get(sector); list_add_tail(§or->list, &sparity->sectors_list); sector->flags = flags; sector->generation = gen; if (csum) { sector->have_csum = 1; memcpy(sector->csum, csum, sctx->fs_info->csum_size); } else { sector->have_csum = 0; } /* Iterate over the stripe range in sectorsize steps */ len -= sectorsize; logical += sectorsize; physical += sectorsize; } WARN_ON(sblock->sector_count == 0); for (index = 0; index < sblock->sector_count; index++) { struct scrub_sector *sector = sblock->sectors[index]; int ret; ret = scrub_add_sector_to_rd_bio(sctx, sector); if (ret) { scrub_block_put(sblock); return ret; } } /* Last one frees, either here or in bio completion for last sector */ scrub_block_put(sblock); return 0; } static int scrub_extent_for_parity(struct scrub_parity *sparity, u64 logical, u32 len, u64 physical, struct btrfs_device *dev, u64 flags, u64 gen, int mirror_num) { struct scrub_ctx *sctx = sparity->sctx; int ret; u8 csum[BTRFS_CSUM_SIZE]; u32 blocksize; if (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state)) { scrub_parity_mark_sectors_error(sparity, logical, len); return 0; } if (flags & BTRFS_EXTENT_FLAG_DATA) { blocksize = sparity->stripe_len; } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { blocksize = sparity->stripe_len; } else { blocksize = sctx->fs_info->sectorsize; WARN_ON(1); } while (len) { u32 l = min(len, blocksize); int have_csum = 0; if (flags & BTRFS_EXTENT_FLAG_DATA) { /* push csums to sbio */ have_csum = scrub_find_csum(sctx, logical, csum); if (have_csum == 0) goto skip; } ret = scrub_sectors_for_parity(sparity, logical, l, physical, dev, flags, gen, mirror_num, have_csum ? csum : NULL); if (ret) return ret; skip: len -= l; logical += l; physical += l; } return 0; } /* * Given a physical address, this will calculate it's * logical offset. if this is a parity stripe, it will return * the most left data stripe's logical offset. * * return 0 if it is a data stripe, 1 means parity stripe. */ static int get_raid56_logic_offset(u64 physical, int num, struct map_lookup *map, u64 *offset, u64 *stripe_start) { int i; int j = 0; u64 last_offset; const int data_stripes = nr_data_stripes(map); last_offset = (physical - map->stripes[num].physical) * data_stripes; if (stripe_start) *stripe_start = last_offset; *offset = last_offset; for (i = 0; i < data_stripes; i++) { u32 stripe_nr; u32 stripe_index; u32 rot; *offset = last_offset + (i << BTRFS_STRIPE_LEN_SHIFT); stripe_nr = (u32)(*offset >> BTRFS_STRIPE_LEN_SHIFT) / data_stripes; /* Work out the disk rotation on this stripe-set */ rot = stripe_nr % map->num_stripes; stripe_nr /= map->num_stripes; /* calculate which stripe this data locates */ rot += i; stripe_index = rot % map->num_stripes; if (stripe_index == num) return 0; if (stripe_index < num) j++; } *offset = last_offset + (j << BTRFS_STRIPE_LEN_SHIFT); return 1; } static void scrub_free_parity(struct scrub_parity *sparity) { struct scrub_ctx *sctx = sparity->sctx; struct scrub_sector *curr, *next; int nbits; nbits = bitmap_weight(&sparity->ebitmap, sparity->nsectors); if (nbits) { spin_lock(&sctx->stat_lock); sctx->stat.read_errors += nbits; sctx->stat.uncorrectable_errors += nbits; spin_unlock(&sctx->stat_lock); } list_for_each_entry_safe(curr, next, &sparity->sectors_list, list) { list_del_init(&curr->list); scrub_sector_put(curr); } kfree(sparity); } static void scrub_parity_bio_endio_worker(struct work_struct *work) { struct scrub_parity *sparity = container_of(work, struct scrub_parity, work); struct scrub_ctx *sctx = sparity->sctx; btrfs_bio_counter_dec(sctx->fs_info); scrub_free_parity(sparity); scrub_pending_bio_dec(sctx); } static void scrub_parity_bio_endio(struct bio *bio) { struct scrub_parity *sparity = bio->bi_private; struct btrfs_fs_info *fs_info = sparity->sctx->fs_info; if (bio->bi_status) bitmap_or(&sparity->ebitmap, &sparity->ebitmap, &sparity->dbitmap, sparity->nsectors); bio_put(bio); INIT_WORK(&sparity->work, scrub_parity_bio_endio_worker); queue_work(fs_info->scrub_parity_workers, &sparity->work); } static void scrub_parity_check_and_repair(struct scrub_parity *sparity) { struct scrub_ctx *sctx = sparity->sctx; struct btrfs_fs_info *fs_info = sctx->fs_info; struct bio *bio; struct btrfs_raid_bio *rbio; struct btrfs_io_context *bioc = NULL; u64 length; int ret; if (!bitmap_andnot(&sparity->dbitmap, &sparity->dbitmap, &sparity->ebitmap, sparity->nsectors)) goto out; length = sparity->logic_end - sparity->logic_start; btrfs_bio_counter_inc_blocked(fs_info); ret = btrfs_map_sblock(fs_info, BTRFS_MAP_WRITE, sparity->logic_start, &length, &bioc); if (ret || !bioc) goto bioc_out; bio = bio_alloc(NULL, BIO_MAX_VECS, REQ_OP_READ, GFP_NOFS); bio->bi_iter.bi_sector = sparity->logic_start >> 9; bio->bi_private = sparity; bio->bi_end_io = scrub_parity_bio_endio; rbio = raid56_parity_alloc_scrub_rbio(bio, bioc, sparity->scrub_dev, &sparity->dbitmap, sparity->nsectors); btrfs_put_bioc(bioc); if (!rbio) goto rbio_out; scrub_pending_bio_inc(sctx); raid56_parity_submit_scrub_rbio(rbio); return; rbio_out: bio_put(bio); bioc_out: btrfs_bio_counter_dec(fs_info); bitmap_or(&sparity->ebitmap, &sparity->ebitmap, &sparity->dbitmap, sparity->nsectors); spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); out: scrub_free_parity(sparity); } static void scrub_parity_get(struct scrub_parity *sparity) { refcount_inc(&sparity->refs); } static void scrub_parity_put(struct scrub_parity *sparity) { if (!refcount_dec_and_test(&sparity->refs)) return; scrub_parity_check_and_repair(sparity); } /* * Return 0 if the extent item range covers any byte of the range. * Return <0 if the extent item is before @search_start. * Return >0 if the extent item is after @start_start + @search_len. */ static int compare_extent_item_range(struct btrfs_path *path, u64 search_start, u64 search_len) { struct btrfs_fs_info *fs_info = path->nodes[0]->fs_info; u64 len; struct btrfs_key key; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); ASSERT(key.type == BTRFS_EXTENT_ITEM_KEY || key.type == BTRFS_METADATA_ITEM_KEY); if (key.type == BTRFS_METADATA_ITEM_KEY) len = fs_info->nodesize; else len = key.offset; if (key.objectid + len <= search_start) return -1; if (key.objectid >= search_start + search_len) return 1; return 0; } /* * Locate one extent item which covers any byte in range * [@search_start, @search_start + @search_length) * * If the path is not initialized, we will initialize the search by doing * a btrfs_search_slot(). * If the path is already initialized, we will use the path as the initial * slot, to avoid duplicated btrfs_search_slot() calls. * * NOTE: If an extent item starts before @search_start, we will still * return the extent item. This is for data extent crossing stripe boundary. * * Return 0 if we found such extent item, and @path will point to the extent item. * Return >0 if no such extent item can be found, and @path will be released. * Return <0 if hit fatal error, and @path will be released. */ static int find_first_extent_item(struct btrfs_root *extent_root, struct btrfs_path *path, u64 search_start, u64 search_len) { struct btrfs_fs_info *fs_info = extent_root->fs_info; struct btrfs_key key; int ret; /* Continue using the existing path */ if (path->nodes[0]) goto search_forward; if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) key.type = BTRFS_METADATA_ITEM_KEY; else key.type = BTRFS_EXTENT_ITEM_KEY; key.objectid = search_start; key.offset = (u64)-1; ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); if (ret < 0) return ret; ASSERT(ret > 0); /* * Here we intentionally pass 0 as @min_objectid, as there could be * an extent item starting before @search_start. */ ret = btrfs_previous_extent_item(extent_root, path, 0); if (ret < 0) return ret; /* * No matter whether we have found an extent item, the next loop will * properly do every check on the key. */ search_forward: while (true) { btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); if (key.objectid >= search_start + search_len) break; if (key.type != BTRFS_METADATA_ITEM_KEY && key.type != BTRFS_EXTENT_ITEM_KEY) goto next; ret = compare_extent_item_range(path, search_start, search_len); if (ret == 0) return ret; if (ret > 0) break; next: path->slots[0]++; if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { ret = btrfs_next_leaf(extent_root, path); if (ret) { /* Either no more item or fatal error */ btrfs_release_path(path); return ret; } } } btrfs_release_path(path); return 1; } static void get_extent_info(struct btrfs_path *path, u64 *extent_start_ret, u64 *size_ret, u64 *flags_ret, u64 *generation_ret) { struct btrfs_key key; struct btrfs_extent_item *ei; btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); ASSERT(key.type == BTRFS_METADATA_ITEM_KEY || key.type == BTRFS_EXTENT_ITEM_KEY); *extent_start_ret = key.objectid; if (key.type == BTRFS_METADATA_ITEM_KEY) *size_ret = path->nodes[0]->fs_info->nodesize; else *size_ret = key.offset; ei = btrfs_item_ptr(path->nodes[0], path->slots[0], struct btrfs_extent_item); *flags_ret = btrfs_extent_flags(path->nodes[0], ei); *generation_ret = btrfs_extent_generation(path->nodes[0], ei); } static bool does_range_cross_boundary(u64 extent_start, u64 extent_len, u64 boundary_start, u64 boudary_len) { return (extent_start < boundary_start && extent_start + extent_len > boundary_start) || (extent_start < boundary_start + boudary_len && extent_start + extent_len > boundary_start + boudary_len); } static int scrub_raid56_data_stripe_for_parity(struct scrub_ctx *sctx, struct scrub_parity *sparity, struct map_lookup *map, struct btrfs_device *sdev, struct btrfs_path *path, u64 logical) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct btrfs_root *extent_root = btrfs_extent_root(fs_info, logical); struct btrfs_root *csum_root = btrfs_csum_root(fs_info, logical); u64 cur_logical = logical; int ret; ASSERT(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK); /* Path must not be populated */ ASSERT(!path->nodes[0]); while (cur_logical < logical + BTRFS_STRIPE_LEN) { struct btrfs_io_context *bioc = NULL; struct btrfs_device *extent_dev; u64 extent_start; u64 extent_size; u64 mapped_length; u64 extent_flags; u64 extent_gen; u64 extent_physical; u64 extent_mirror_num; ret = find_first_extent_item(extent_root, path, cur_logical, logical + BTRFS_STRIPE_LEN - cur_logical); /* No more extent item in this data stripe */ if (ret > 0) { ret = 0; break; } if (ret < 0) break; get_extent_info(path, &extent_start, &extent_size, &extent_flags, &extent_gen); /* Metadata should not cross stripe boundaries */ if ((extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) && does_range_cross_boundary(extent_start, extent_size, logical, BTRFS_STRIPE_LEN)) { btrfs_err(fs_info, "scrub: tree block %llu spanning stripes, ignored. logical=%llu", extent_start, logical); spin_lock(&sctx->stat_lock); sctx->stat.uncorrectable_errors++; spin_unlock(&sctx->stat_lock); cur_logical += extent_size; continue; } /* Skip hole range which doesn't have any extent */ cur_logical = max(extent_start, cur_logical); /* Truncate the range inside this data stripe */ extent_size = min(extent_start + extent_size, logical + BTRFS_STRIPE_LEN) - cur_logical; extent_start = cur_logical; ASSERT(extent_size <= U32_MAX); scrub_parity_mark_sectors_data(sparity, extent_start, extent_size); mapped_length = extent_size; ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, extent_start, &mapped_length, &bioc, 0); if (!ret && (!bioc || mapped_length < extent_size)) ret = -EIO; if (ret) { btrfs_put_bioc(bioc); scrub_parity_mark_sectors_error(sparity, extent_start, extent_size); break; } extent_physical = bioc->stripes[0].physical; extent_mirror_num = bioc->mirror_num; extent_dev = bioc->stripes[0].dev; btrfs_put_bioc(bioc); ret = btrfs_lookup_csums_list(csum_root, extent_start, extent_start + extent_size - 1, &sctx->csum_list, 1, false); if (ret) { scrub_parity_mark_sectors_error(sparity, extent_start, extent_size); break; } ret = scrub_extent_for_parity(sparity, extent_start, extent_size, extent_physical, extent_dev, extent_flags, extent_gen, extent_mirror_num); scrub_free_csums(sctx); if (ret) { scrub_parity_mark_sectors_error(sparity, extent_start, extent_size); break; } cond_resched(); cur_logical += extent_size; } btrfs_release_path(path); return ret; } static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx, struct map_lookup *map, struct btrfs_device *sdev, u64 logic_start, u64 logic_end) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct btrfs_path *path; u64 cur_logical; int ret; struct scrub_parity *sparity; int nsectors; path = btrfs_alloc_path(); if (!path) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); return -ENOMEM; } path->search_commit_root = 1; path->skip_locking = 1; nsectors = BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits; ASSERT(nsectors <= BITS_PER_LONG); sparity = kzalloc(sizeof(struct scrub_parity), GFP_NOFS); if (!sparity) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); btrfs_free_path(path); return -ENOMEM; } sparity->stripe_len = BTRFS_STRIPE_LEN; sparity->nsectors = nsectors; sparity->sctx = sctx; sparity->scrub_dev = sdev; sparity->logic_start = logic_start; sparity->logic_end = logic_end; refcount_set(&sparity->refs, 1); INIT_LIST_HEAD(&sparity->sectors_list); ret = 0; for (cur_logical = logic_start; cur_logical < logic_end; cur_logical += BTRFS_STRIPE_LEN) { ret = scrub_raid56_data_stripe_for_parity(sctx, sparity, map, sdev, path, cur_logical); if (ret < 0) break; } scrub_parity_put(sparity); scrub_submit(sctx); mutex_lock(&sctx->wr_lock); scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); btrfs_free_path(path); return ret < 0 ? ret : 0; } static int sync_write_pointer_for_zoned(struct scrub_ctx *sctx, u64 logical, u64 physical, u64 physical_end) { struct btrfs_fs_info *fs_info = sctx->fs_info; int ret = 0; if (!btrfs_is_zoned(fs_info)) return 0; wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); mutex_lock(&sctx->wr_lock); if (sctx->write_pointer < physical_end) { ret = btrfs_sync_zone_write_pointer(sctx->wr_tgtdev, logical, physical, sctx->write_pointer); if (ret) btrfs_err(fs_info, "zoned: failed to recover write pointer"); } mutex_unlock(&sctx->wr_lock); btrfs_dev_clear_zone_empty(sctx->wr_tgtdev, physical); return ret; } static void fill_one_extent_info(struct btrfs_fs_info *fs_info, struct scrub_stripe *stripe, u64 extent_start, u64 extent_len, u64 extent_flags, u64 extent_gen) { for (u64 cur_logical = max(stripe->logical, extent_start); cur_logical < min(stripe->logical + BTRFS_STRIPE_LEN, extent_start + extent_len); cur_logical += fs_info->sectorsize) { const int nr_sector = (cur_logical - stripe->logical) >> fs_info->sectorsize_bits; struct scrub_sector_verification *sector = &stripe->sectors[nr_sector]; set_bit(nr_sector, &stripe->extent_sector_bitmap); if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { sector->is_metadata = true; sector->generation = extent_gen; } } } static void scrub_stripe_reset_bitmaps(struct scrub_stripe *stripe) { stripe->extent_sector_bitmap = 0; stripe->init_error_bitmap = 0; stripe->error_bitmap = 0; stripe->io_error_bitmap = 0; stripe->csum_error_bitmap = 0; stripe->meta_error_bitmap = 0; } /* * Locate one stripe which has at least one extent in its range. * * Return 0 if found such stripe, and store its info into @stripe. * Return >0 if there is no such stripe in the specified range. * Return <0 for error. */ static int scrub_find_fill_first_stripe(struct btrfs_block_group *bg, struct btrfs_device *dev, u64 physical, int mirror_num, u64 logical_start, u32 logical_len, struct scrub_stripe *stripe) { struct btrfs_fs_info *fs_info = bg->fs_info; struct btrfs_root *extent_root = btrfs_extent_root(fs_info, bg->start); struct btrfs_root *csum_root = btrfs_csum_root(fs_info, bg->start); const u64 logical_end = logical_start + logical_len; struct btrfs_path path = { 0 }; u64 cur_logical = logical_start; u64 stripe_end; u64 extent_start; u64 extent_len; u64 extent_flags; u64 extent_gen; int ret; memset(stripe->sectors, 0, sizeof(struct scrub_sector_verification) * stripe->nr_sectors); scrub_stripe_reset_bitmaps(stripe); /* The range must be inside the bg. */ ASSERT(logical_start >= bg->start && logical_end <= bg->start + bg->length); path.search_commit_root = 1; path.skip_locking = 1; ret = find_first_extent_item(extent_root, &path, logical_start, logical_len); /* Either error or not found. */ if (ret) goto out; get_extent_info(&path, &extent_start, &extent_len, &extent_flags, &extent_gen); if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) stripe->nr_meta_extents++; if (extent_flags & BTRFS_EXTENT_FLAG_DATA) stripe->nr_data_extents++; cur_logical = max(extent_start, cur_logical); /* * Round down to stripe boundary. * * The extra calculation against bg->start is to handle block groups * whose logical bytenr is not BTRFS_STRIPE_LEN aligned. */ stripe->logical = round_down(cur_logical - bg->start, BTRFS_STRIPE_LEN) + bg->start; stripe->physical = physical + stripe->logical - logical_start; stripe->dev = dev; stripe->bg = bg; stripe->mirror_num = mirror_num; stripe_end = stripe->logical + BTRFS_STRIPE_LEN - 1; /* Fill the first extent info into stripe->sectors[] array. */ fill_one_extent_info(fs_info, stripe, extent_start, extent_len, extent_flags, extent_gen); cur_logical = extent_start + extent_len; /* Fill the extent info for the remaining sectors. */ while (cur_logical <= stripe_end) { ret = find_first_extent_item(extent_root, &path, cur_logical, stripe_end - cur_logical + 1); if (ret < 0) goto out; if (ret > 0) { ret = 0; break; } get_extent_info(&path, &extent_start, &extent_len, &extent_flags, &extent_gen); if (extent_flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) stripe->nr_meta_extents++; if (extent_flags & BTRFS_EXTENT_FLAG_DATA) stripe->nr_data_extents++; fill_one_extent_info(fs_info, stripe, extent_start, extent_len, extent_flags, extent_gen); cur_logical = extent_start + extent_len; } /* Now fill the data csum. */ if (bg->flags & BTRFS_BLOCK_GROUP_DATA) { int sector_nr; unsigned long csum_bitmap = 0; /* Csum space should have already been allocated. */ ASSERT(stripe->csums); /* * Our csum bitmap should be large enough, as BTRFS_STRIPE_LEN * should contain at most 16 sectors. */ ASSERT(BITS_PER_LONG >= BTRFS_STRIPE_LEN >> fs_info->sectorsize_bits); ret = btrfs_lookup_csums_bitmap(csum_root, stripe->logical, stripe_end, stripe->csums, &csum_bitmap, true); if (ret < 0) goto out; if (ret > 0) ret = 0; for_each_set_bit(sector_nr, &csum_bitmap, stripe->nr_sectors) { stripe->sectors[sector_nr].csum = stripe->csums + sector_nr * fs_info->csum_size; } } set_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state); out: btrfs_release_path(&path); return ret; } static void scrub_reset_stripe(struct scrub_stripe *stripe) { scrub_stripe_reset_bitmaps(stripe); stripe->nr_meta_extents = 0; stripe->nr_data_extents = 0; stripe->state = 0; for (int i = 0; i < stripe->nr_sectors; i++) { stripe->sectors[i].is_metadata = false; stripe->sectors[i].csum = NULL; stripe->sectors[i].generation = 0; } } static void scrub_submit_initial_read(struct scrub_ctx *sctx, struct scrub_stripe *stripe) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct btrfs_bio *bbio; int mirror = stripe->mirror_num; ASSERT(stripe->bg); ASSERT(stripe->mirror_num > 0); ASSERT(test_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &stripe->state)); bbio = btrfs_bio_alloc(SCRUB_STRIPE_PAGES, REQ_OP_READ, fs_info, scrub_read_endio, stripe); /* Read the whole stripe. */ bbio->bio.bi_iter.bi_sector = stripe->logical >> SECTOR_SHIFT; for (int i = 0; i < BTRFS_STRIPE_LEN >> PAGE_SHIFT; i++) { int ret; ret = bio_add_page(&bbio->bio, stripe->pages[i], PAGE_SIZE, 0); /* We should have allocated enough bio vectors. */ ASSERT(ret == PAGE_SIZE); } atomic_inc(&stripe->pending_io); /* * For dev-replace, either user asks to avoid the source dev, or * the device is missing, we try the next mirror instead. */ if (sctx->is_dev_replace && (fs_info->dev_replace.cont_reading_from_srcdev_mode == BTRFS_DEV_REPLACE_ITEM_CONT_READING_FROM_SRCDEV_MODE_AVOID || !stripe->dev->bdev)) { int num_copies = btrfs_num_copies(fs_info, stripe->bg->start, stripe->bg->length); mirror = calc_next_mirror(mirror, num_copies); } btrfs_submit_bio(bbio, mirror); } static void flush_scrub_stripes(struct scrub_ctx *sctx) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct scrub_stripe *stripe; const int nr_stripes = sctx->cur_stripe; if (!nr_stripes) return; ASSERT(test_bit(SCRUB_STRIPE_FLAG_INITIALIZED, &sctx->stripes[0].state)); scrub_throttle_dev_io(sctx, sctx->stripes[0].dev, nr_stripes << BTRFS_STRIPE_LEN_SHIFT); for (int i = 0; i < nr_stripes; i++) { stripe = &sctx->stripes[i]; scrub_submit_initial_read(sctx, stripe); } for (int i = 0; i < nr_stripes; i++) { stripe = &sctx->stripes[i]; wait_event(stripe->repair_wait, test_bit(SCRUB_STRIPE_FLAG_REPAIR_DONE, &stripe->state)); } /* * Submit the repaired sectors. For zoned case, we cannot do repair * in-place, but queue the bg to be relocated. */ if (btrfs_is_zoned(fs_info)) { for (int i = 0; i < nr_stripes; i++) { stripe = &sctx->stripes[i]; if (!bitmap_empty(&stripe->error_bitmap, stripe->nr_sectors)) { btrfs_repair_one_zone(fs_info, sctx->stripes[0].bg->start); break; } } } else { for (int i = 0; i < nr_stripes; i++) { unsigned long repaired; stripe = &sctx->stripes[i]; bitmap_andnot(&repaired, &stripe->init_error_bitmap, &stripe->error_bitmap, stripe->nr_sectors); scrub_write_sectors(sctx, stripe, repaired, false); } } /* Submit for dev-replace. */ if (sctx->is_dev_replace) { for (int i = 0; i < nr_stripes; i++) { unsigned long good; stripe = &sctx->stripes[i]; ASSERT(stripe->dev == fs_info->dev_replace.srcdev); bitmap_andnot(&good, &stripe->extent_sector_bitmap, &stripe->error_bitmap, stripe->nr_sectors); scrub_write_sectors(sctx, stripe, good, true); } } /* Wait for the above writebacks to finish. */ for (int i = 0; i < nr_stripes; i++) { stripe = &sctx->stripes[i]; wait_scrub_stripe_io(stripe); scrub_reset_stripe(stripe); } sctx->cur_stripe = 0; } static int queue_scrub_stripe(struct scrub_ctx *sctx, struct btrfs_block_group *bg, struct btrfs_device *dev, int mirror_num, u64 logical, u32 length, u64 physical) { struct scrub_stripe *stripe; int ret; /* No available slot, submit all stripes and wait for them. */ if (sctx->cur_stripe >= SCRUB_STRIPES_PER_SCTX) flush_scrub_stripes(sctx); stripe = &sctx->stripes[sctx->cur_stripe]; /* We can queue one stripe using the remaining slot. */ scrub_reset_stripe(stripe); ret = scrub_find_fill_first_stripe(bg, dev, physical, mirror_num, logical, length, stripe); /* Either >0 as no more extents or <0 for error. */ if (ret) return ret; sctx->cur_stripe++; return 0; } /* * Scrub one range which can only has simple mirror based profile. * (Including all range in SINGLE/DUP/RAID1/RAID1C*, and each stripe in * RAID0/RAID10). * * Since we may need to handle a subset of block group, we need @logical_start * and @logical_length parameter. */ static int scrub_simple_mirror(struct scrub_ctx *sctx, struct btrfs_block_group *bg, struct map_lookup *map, u64 logical_start, u64 logical_length, struct btrfs_device *device, u64 physical, int mirror_num) { struct btrfs_fs_info *fs_info = sctx->fs_info; const u64 logical_end = logical_start + logical_length; /* An artificial limit, inherit from old scrub behavior */ struct btrfs_path path = { 0 }; u64 cur_logical = logical_start; int ret; /* The range must be inside the bg */ ASSERT(logical_start >= bg->start && logical_end <= bg->start + bg->length); path.search_commit_root = 1; path.skip_locking = 1; /* Go through each extent items inside the logical range */ while (cur_logical < logical_end) { u64 cur_physical = physical + cur_logical - logical_start; /* Canceled? */ if (atomic_read(&fs_info->scrub_cancel_req) || atomic_read(&sctx->cancel_req)) { ret = -ECANCELED; break; } /* Paused? */ if (atomic_read(&fs_info->scrub_pause_req)) { /* Push queued extents */ sctx->flush_all_writes = true; scrub_submit(sctx); mutex_lock(&sctx->wr_lock); scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); sctx->flush_all_writes = false; scrub_blocked_if_needed(fs_info); } /* Block group removed? */ spin_lock(&bg->lock); if (test_bit(BLOCK_GROUP_FLAG_REMOVED, &bg->runtime_flags)) { spin_unlock(&bg->lock); ret = 0; break; } spin_unlock(&bg->lock); ret = queue_scrub_stripe(sctx, bg, device, mirror_num, cur_logical, logical_end - cur_logical, cur_physical); if (ret > 0) { /* No more extent, just update the accounting */ sctx->stat.last_physical = physical + logical_length; ret = 0; break; } if (ret < 0) break; ASSERT(sctx->cur_stripe > 0); cur_logical = sctx->stripes[sctx->cur_stripe - 1].logical + BTRFS_STRIPE_LEN; /* Don't hold CPU for too long time */ cond_resched(); } btrfs_release_path(&path); return ret; } /* Calculate the full stripe length for simple stripe based profiles */ static u64 simple_stripe_full_stripe_len(const struct map_lookup *map) { ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)); return (map->num_stripes / map->sub_stripes) << BTRFS_STRIPE_LEN_SHIFT; } /* Get the logical bytenr for the stripe */ static u64 simple_stripe_get_logical(struct map_lookup *map, struct btrfs_block_group *bg, int stripe_index) { ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)); ASSERT(stripe_index < map->num_stripes); /* * (stripe_index / sub_stripes) gives how many data stripes we need to * skip. */ return ((stripe_index / map->sub_stripes) << BTRFS_STRIPE_LEN_SHIFT) + bg->start; } /* Get the mirror number for the stripe */ static int simple_stripe_mirror_num(struct map_lookup *map, int stripe_index) { ASSERT(map->type & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)); ASSERT(stripe_index < map->num_stripes); /* For RAID0, it's fixed to 1, for RAID10 it's 0,1,0,1... */ return stripe_index % map->sub_stripes + 1; } static int scrub_simple_stripe(struct scrub_ctx *sctx, struct btrfs_block_group *bg, struct map_lookup *map, struct btrfs_device *device, int stripe_index) { const u64 logical_increment = simple_stripe_full_stripe_len(map); const u64 orig_logical = simple_stripe_get_logical(map, bg, stripe_index); const u64 orig_physical = map->stripes[stripe_index].physical; const int mirror_num = simple_stripe_mirror_num(map, stripe_index); u64 cur_logical = orig_logical; u64 cur_physical = orig_physical; int ret = 0; while (cur_logical < bg->start + bg->length) { /* * Inside each stripe, RAID0 is just SINGLE, and RAID10 is * just RAID1, so we can reuse scrub_simple_mirror() to scrub * this stripe. */ ret = scrub_simple_mirror(sctx, bg, map, cur_logical, BTRFS_STRIPE_LEN, device, cur_physical, mirror_num); if (ret) return ret; /* Skip to next stripe which belongs to the target device */ cur_logical += logical_increment; /* For physical offset, we just go to next stripe */ cur_physical += BTRFS_STRIPE_LEN; } return ret; } static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, struct btrfs_block_group *bg, struct extent_map *em, struct btrfs_device *scrub_dev, int stripe_index) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct map_lookup *map = em->map_lookup; const u64 profile = map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK; const u64 chunk_logical = bg->start; int ret; u64 physical = map->stripes[stripe_index].physical; const u64 dev_stripe_len = btrfs_calc_stripe_length(em); const u64 physical_end = physical + dev_stripe_len; u64 logical; u64 logic_end; /* The logical increment after finishing one stripe */ u64 increment; /* Offset inside the chunk */ u64 offset; u64 stripe_logical; u64 stripe_end; int stop_loop = 0; wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); scrub_blocked_if_needed(fs_info); if (sctx->is_dev_replace && btrfs_dev_is_sequential(sctx->wr_tgtdev, physical)) { mutex_lock(&sctx->wr_lock); sctx->write_pointer = physical; mutex_unlock(&sctx->wr_lock); sctx->flush_all_writes = true; } /* * There used to be a big double loop to handle all profiles using the * same routine, which grows larger and more gross over time. * * So here we handle each profile differently, so simpler profiles * have simpler scrubbing function. */ if (!(profile & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10 | BTRFS_BLOCK_GROUP_RAID56_MASK))) { /* * Above check rules out all complex profile, the remaining * profiles are SINGLE|DUP|RAID1|RAID1C*, which is simple * mirrored duplication without stripe. * * Only @physical and @mirror_num needs to calculated using * @stripe_index. */ ret = scrub_simple_mirror(sctx, bg, map, bg->start, bg->length, scrub_dev, map->stripes[stripe_index].physical, stripe_index + 1); offset = 0; goto out; } if (profile & (BTRFS_BLOCK_GROUP_RAID0 | BTRFS_BLOCK_GROUP_RAID10)) { ret = scrub_simple_stripe(sctx, bg, map, scrub_dev, stripe_index); offset = (stripe_index / map->sub_stripes) << BTRFS_STRIPE_LEN_SHIFT; goto out; } /* Only RAID56 goes through the old code */ ASSERT(map->type & BTRFS_BLOCK_GROUP_RAID56_MASK); ret = 0; /* Calculate the logical end of the stripe */ get_raid56_logic_offset(physical_end, stripe_index, map, &logic_end, NULL); logic_end += chunk_logical; /* Initialize @offset in case we need to go to out: label */ get_raid56_logic_offset(physical, stripe_index, map, &offset, NULL); increment = nr_data_stripes(map) << BTRFS_STRIPE_LEN_SHIFT; /* * Due to the rotation, for RAID56 it's better to iterate each stripe * using their physical offset. */ while (physical < physical_end) { ret = get_raid56_logic_offset(physical, stripe_index, map, &logical, &stripe_logical); logical += chunk_logical; if (ret) { /* it is parity strip */ stripe_logical += chunk_logical; stripe_end = stripe_logical + increment; ret = scrub_raid56_parity(sctx, map, scrub_dev, stripe_logical, stripe_end); if (ret) goto out; goto next; } /* * Now we're at a data stripe, scrub each extents in the range. * * At this stage, if we ignore the repair part, inside each data * stripe it is no different than SINGLE profile. * We can reuse scrub_simple_mirror() here, as the repair part * is still based on @mirror_num. */ ret = scrub_simple_mirror(sctx, bg, map, logical, BTRFS_STRIPE_LEN, scrub_dev, physical, 1); if (ret < 0) goto out; next: logical += increment; physical += BTRFS_STRIPE_LEN; spin_lock(&sctx->stat_lock); if (stop_loop) sctx->stat.last_physical = map->stripes[stripe_index].physical + dev_stripe_len; else sctx->stat.last_physical = physical; spin_unlock(&sctx->stat_lock); if (stop_loop) break; } out: /* push queued extents */ scrub_submit(sctx); mutex_lock(&sctx->wr_lock); scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); flush_scrub_stripes(sctx); if (sctx->is_dev_replace && ret >= 0) { int ret2; ret2 = sync_write_pointer_for_zoned(sctx, chunk_logical + offset, map->stripes[stripe_index].physical, physical_end); if (ret2) ret = ret2; } return ret < 0 ? ret : 0; } static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx, struct btrfs_block_group *bg, struct btrfs_device *scrub_dev, u64 dev_offset, u64 dev_extent_len) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct extent_map_tree *map_tree = &fs_info->mapping_tree; struct map_lookup *map; struct extent_map *em; int i; int ret = 0; read_lock(&map_tree->lock); em = lookup_extent_mapping(map_tree, bg->start, bg->length); read_unlock(&map_tree->lock); if (!em) { /* * Might have been an unused block group deleted by the cleaner * kthread or relocation. */ spin_lock(&bg->lock); if (!test_bit(BLOCK_GROUP_FLAG_REMOVED, &bg->runtime_flags)) ret = -EINVAL; spin_unlock(&bg->lock); return ret; } if (em->start != bg->start) goto out; if (em->len < dev_extent_len) goto out; map = em->map_lookup; for (i = 0; i < map->num_stripes; ++i) { if (map->stripes[i].dev->bdev == scrub_dev->bdev && map->stripes[i].physical == dev_offset) { ret = scrub_stripe(sctx, bg, em, scrub_dev, i); if (ret) goto out; } } out: free_extent_map(em); return ret; } static int finish_extent_writes_for_zoned(struct btrfs_root *root, struct btrfs_block_group *cache) { struct btrfs_fs_info *fs_info = cache->fs_info; struct btrfs_trans_handle *trans; if (!btrfs_is_zoned(fs_info)) return 0; btrfs_wait_block_group_reservations(cache); btrfs_wait_nocow_writers(cache); btrfs_wait_ordered_roots(fs_info, U64_MAX, cache->start, cache->length); trans = btrfs_join_transaction(root); if (IS_ERR(trans)) return PTR_ERR(trans); return btrfs_commit_transaction(trans); } static noinline_for_stack int scrub_enumerate_chunks(struct scrub_ctx *sctx, struct btrfs_device *scrub_dev, u64 start, u64 end) { struct btrfs_dev_extent *dev_extent = NULL; struct btrfs_path *path; struct btrfs_fs_info *fs_info = sctx->fs_info; struct btrfs_root *root = fs_info->dev_root; u64 chunk_offset; int ret = 0; int ro_set; int slot; struct extent_buffer *l; struct btrfs_key key; struct btrfs_key found_key; struct btrfs_block_group *cache; struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->reada = READA_FORWARD; path->search_commit_root = 1; path->skip_locking = 1; key.objectid = scrub_dev->devid; key.offset = 0ull; key.type = BTRFS_DEV_EXTENT_KEY; while (1) { u64 dev_extent_len; ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) break; if (ret > 0) { if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) { ret = btrfs_next_leaf(root, path); if (ret < 0) break; if (ret > 0) { ret = 0; break; } } else { ret = 0; } } l = path->nodes[0]; slot = path->slots[0]; btrfs_item_key_to_cpu(l, &found_key, slot); if (found_key.objectid != scrub_dev->devid) break; if (found_key.type != BTRFS_DEV_EXTENT_KEY) break; if (found_key.offset >= end) break; if (found_key.offset < key.offset) break; dev_extent = btrfs_item_ptr(l, slot, struct btrfs_dev_extent); dev_extent_len = btrfs_dev_extent_length(l, dev_extent); if (found_key.offset + dev_extent_len <= start) goto skip; chunk_offset = btrfs_dev_extent_chunk_offset(l, dev_extent); /* * get a reference on the corresponding block group to prevent * the chunk from going away while we scrub it */ cache = btrfs_lookup_block_group(fs_info, chunk_offset); /* some chunks are removed but not committed to disk yet, * continue scrubbing */ if (!cache) goto skip; ASSERT(cache->start <= chunk_offset); /* * We are using the commit root to search for device extents, so * that means we could have found a device extent item from a * block group that was deleted in the current transaction. The * logical start offset of the deleted block group, stored at * @chunk_offset, might be part of the logical address range of * a new block group (which uses different physical extents). * In this case btrfs_lookup_block_group() has returned the new * block group, and its start address is less than @chunk_offset. * * We skip such new block groups, because it's pointless to * process them, as we won't find their extents because we search * for them using the commit root of the extent tree. For a device * replace it's also fine to skip it, we won't miss copying them * to the target device because we have the write duplication * setup through the regular write path (by btrfs_map_block()), * and we have committed a transaction when we started the device * replace, right after setting up the device replace state. */ if (cache->start < chunk_offset) { btrfs_put_block_group(cache); goto skip; } if (sctx->is_dev_replace && btrfs_is_zoned(fs_info)) { if (!test_bit(BLOCK_GROUP_FLAG_TO_COPY, &cache->runtime_flags)) { btrfs_put_block_group(cache); goto skip; } } /* * Make sure that while we are scrubbing the corresponding block * group doesn't get its logical address and its device extents * reused for another block group, which can possibly be of a * different type and different profile. We do this to prevent * false error detections and crashes due to bogus attempts to * repair extents. */ spin_lock(&cache->lock); if (test_bit(BLOCK_GROUP_FLAG_REMOVED, &cache->runtime_flags)) { spin_unlock(&cache->lock); btrfs_put_block_group(cache); goto skip; } btrfs_freeze_block_group(cache); spin_unlock(&cache->lock); /* * we need call btrfs_inc_block_group_ro() with scrubs_paused, * to avoid deadlock caused by: * btrfs_inc_block_group_ro() * -> btrfs_wait_for_commit() * -> btrfs_commit_transaction() * -> btrfs_scrub_pause() */ scrub_pause_on(fs_info); /* * Don't do chunk preallocation for scrub. * * This is especially important for SYSTEM bgs, or we can hit * -EFBIG from btrfs_finish_chunk_alloc() like: * 1. The only SYSTEM bg is marked RO. * Since SYSTEM bg is small, that's pretty common. * 2. New SYSTEM bg will be allocated * Due to regular version will allocate new chunk. * 3. New SYSTEM bg is empty and will get cleaned up * Before cleanup really happens, it's marked RO again. * 4. Empty SYSTEM bg get scrubbed * We go back to 2. * * This can easily boost the amount of SYSTEM chunks if cleaner * thread can't be triggered fast enough, and use up all space * of btrfs_super_block::sys_chunk_array * * While for dev replace, we need to try our best to mark block * group RO, to prevent race between: * - Write duplication * Contains latest data * - Scrub copy * Contains data from commit tree * * If target block group is not marked RO, nocow writes can * be overwritten by scrub copy, causing data corruption. * So for dev-replace, it's not allowed to continue if a block * group is not RO. */ ret = btrfs_inc_block_group_ro(cache, sctx->is_dev_replace); if (!ret && sctx->is_dev_replace) { ret = finish_extent_writes_for_zoned(root, cache); if (ret) { btrfs_dec_block_group_ro(cache); scrub_pause_off(fs_info); btrfs_put_block_group(cache); break; } } if (ret == 0) { ro_set = 1; } else if (ret == -ENOSPC && !sctx->is_dev_replace) { /* * btrfs_inc_block_group_ro return -ENOSPC when it * failed in creating new chunk for metadata. * It is not a problem for scrub, because * metadata are always cowed, and our scrub paused * commit_transactions. */ ro_set = 0; } else if (ret == -ETXTBSY) { btrfs_warn(fs_info, "skipping scrub of block group %llu due to active swapfile", cache->start); scrub_pause_off(fs_info); ret = 0; goto skip_unfreeze; } else { btrfs_warn(fs_info, "failed setting block group ro: %d", ret); btrfs_unfreeze_block_group(cache); btrfs_put_block_group(cache); scrub_pause_off(fs_info); break; } /* * Now the target block is marked RO, wait for nocow writes to * finish before dev-replace. * COW is fine, as COW never overwrites extents in commit tree. */ if (sctx->is_dev_replace) { btrfs_wait_nocow_writers(cache); btrfs_wait_ordered_roots(fs_info, U64_MAX, cache->start, cache->length); } scrub_pause_off(fs_info); down_write(&dev_replace->rwsem); dev_replace->cursor_right = found_key.offset + dev_extent_len; dev_replace->cursor_left = found_key.offset; dev_replace->item_needs_writeback = 1; up_write(&dev_replace->rwsem); ret = scrub_chunk(sctx, cache, scrub_dev, found_key.offset, dev_extent_len); /* * flush, submit all pending read and write bios, afterwards * wait for them. * Note that in the dev replace case, a read request causes * write requests that are submitted in the read completion * worker. Therefore in the current situation, it is required * that all write requests are flushed, so that all read and * write requests are really completed when bios_in_flight * changes to 0. */ sctx->flush_all_writes = true; scrub_submit(sctx); mutex_lock(&sctx->wr_lock); scrub_wr_submit(sctx); mutex_unlock(&sctx->wr_lock); wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); scrub_pause_on(fs_info); /* * must be called before we decrease @scrub_paused. * make sure we don't block transaction commit while * we are waiting pending workers finished. */ wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0); sctx->flush_all_writes = false; scrub_pause_off(fs_info); if (sctx->is_dev_replace && !btrfs_finish_block_group_to_copy(dev_replace->srcdev, cache, found_key.offset)) ro_set = 0; down_write(&dev_replace->rwsem); dev_replace->cursor_left = dev_replace->cursor_right; dev_replace->item_needs_writeback = 1; up_write(&dev_replace->rwsem); if (ro_set) btrfs_dec_block_group_ro(cache); /* * We might have prevented the cleaner kthread from deleting * this block group if it was already unused because we raced * and set it to RO mode first. So add it back to the unused * list, otherwise it might not ever be deleted unless a manual * balance is triggered or it becomes used and unused again. */ spin_lock(&cache->lock); if (!test_bit(BLOCK_GROUP_FLAG_REMOVED, &cache->runtime_flags) && !cache->ro && cache->reserved == 0 && cache->used == 0) { spin_unlock(&cache->lock); if (btrfs_test_opt(fs_info, DISCARD_ASYNC)) btrfs_discard_queue_work(&fs_info->discard_ctl, cache); else btrfs_mark_bg_unused(cache); } else { spin_unlock(&cache->lock); } skip_unfreeze: btrfs_unfreeze_block_group(cache); btrfs_put_block_group(cache); if (ret) break; if (sctx->is_dev_replace && atomic64_read(&dev_replace->num_write_errors) > 0) { ret = -EIO; break; } if (sctx->stat.malloc_errors > 0) { ret = -ENOMEM; break; } skip: key.offset = found_key.offset + dev_extent_len; btrfs_release_path(path); } btrfs_free_path(path); return ret; } static int scrub_one_super(struct scrub_ctx *sctx, struct btrfs_device *dev, struct page *page, u64 physical, u64 generation) { struct btrfs_fs_info *fs_info = sctx->fs_info; struct bio_vec bvec; struct bio bio; struct btrfs_super_block *sb = page_address(page); int ret; bio_init(&bio, dev->bdev, &bvec, 1, REQ_OP_READ); bio.bi_iter.bi_sector = physical >> SECTOR_SHIFT; __bio_add_page(&bio, page, BTRFS_SUPER_INFO_SIZE, 0); ret = submit_bio_wait(&bio); bio_uninit(&bio); if (ret < 0) return ret; ret = btrfs_check_super_csum(fs_info, sb); if (ret != 0) { btrfs_err_rl(fs_info, "super block at physical %llu devid %llu has bad csum", physical, dev->devid); return -EIO; } if (btrfs_super_generation(sb) != generation) { btrfs_err_rl(fs_info, "super block at physical %llu devid %llu has bad generation %llu expect %llu", physical, dev->devid, btrfs_super_generation(sb), generation); return -EUCLEAN; } return btrfs_validate_super(fs_info, sb, -1); } static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx, struct btrfs_device *scrub_dev) { int i; u64 bytenr; u64 gen; int ret = 0; struct page *page; struct btrfs_fs_info *fs_info = sctx->fs_info; if (BTRFS_FS_ERROR(fs_info)) return -EROFS; page = alloc_page(GFP_KERNEL); if (!page) { spin_lock(&sctx->stat_lock); sctx->stat.malloc_errors++; spin_unlock(&sctx->stat_lock); return -ENOMEM; } /* Seed devices of a new filesystem has their own generation. */ if (scrub_dev->fs_devices != fs_info->fs_devices) gen = scrub_dev->generation; else gen = fs_info->last_trans_committed; for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) { bytenr = btrfs_sb_offset(i); if (bytenr + BTRFS_SUPER_INFO_SIZE > scrub_dev->commit_total_bytes) break; if (!btrfs_check_super_location(scrub_dev, bytenr)) continue; ret = scrub_one_super(sctx, scrub_dev, page, bytenr, gen); if (ret) { spin_lock(&sctx->stat_lock); sctx->stat.super_errors++; spin_unlock(&sctx->stat_lock); } } __free_page(page); return 0; } static void scrub_workers_put(struct btrfs_fs_info *fs_info) { if (refcount_dec_and_mutex_lock(&fs_info->scrub_workers_refcnt, &fs_info->scrub_lock)) { struct workqueue_struct *scrub_workers = fs_info->scrub_workers; struct workqueue_struct *scrub_wr_comp = fs_info->scrub_wr_completion_workers; struct workqueue_struct *scrub_parity = fs_info->scrub_parity_workers; fs_info->scrub_workers = NULL; fs_info->scrub_wr_completion_workers = NULL; fs_info->scrub_parity_workers = NULL; mutex_unlock(&fs_info->scrub_lock); if (scrub_workers) destroy_workqueue(scrub_workers); if (scrub_wr_comp) destroy_workqueue(scrub_wr_comp); if (scrub_parity) destroy_workqueue(scrub_parity); } } /* * get a reference count on fs_info->scrub_workers. start worker if necessary */ static noinline_for_stack int scrub_workers_get(struct btrfs_fs_info *fs_info, int is_dev_replace) { struct workqueue_struct *scrub_workers = NULL; struct workqueue_struct *scrub_wr_comp = NULL; struct workqueue_struct *scrub_parity = NULL; unsigned int flags = WQ_FREEZABLE | WQ_UNBOUND; int max_active = fs_info->thread_pool_size; int ret = -ENOMEM; if (refcount_inc_not_zero(&fs_info->scrub_workers_refcnt)) return 0; scrub_workers = alloc_workqueue("btrfs-scrub", flags, is_dev_replace ? 1 : max_active); if (!scrub_workers) goto fail_scrub_workers; scrub_wr_comp = alloc_workqueue("btrfs-scrubwrc", flags, max_active); if (!scrub_wr_comp) goto fail_scrub_wr_completion_workers; scrub_parity = alloc_workqueue("btrfs-scrubparity", flags, max_active); if (!scrub_parity) goto fail_scrub_parity_workers; mutex_lock(&fs_info->scrub_lock); if (refcount_read(&fs_info->scrub_workers_refcnt) == 0) { ASSERT(fs_info->scrub_workers == NULL && fs_info->scrub_wr_completion_workers == NULL && fs_info->scrub_parity_workers == NULL); fs_info->scrub_workers = scrub_workers; fs_info->scrub_wr_completion_workers = scrub_wr_comp; fs_info->scrub_parity_workers = scrub_parity; refcount_set(&fs_info->scrub_workers_refcnt, 1); mutex_unlock(&fs_info->scrub_lock); return 0; } /* Other thread raced in and created the workers for us */ refcount_inc(&fs_info->scrub_workers_refcnt); mutex_unlock(&fs_info->scrub_lock); ret = 0; destroy_workqueue(scrub_parity); fail_scrub_parity_workers: destroy_workqueue(scrub_wr_comp); fail_scrub_wr_completion_workers: destroy_workqueue(scrub_workers); fail_scrub_workers: return ret; } int btrfs_scrub_dev(struct btrfs_fs_info *fs_info, u64 devid, u64 start, u64 end, struct btrfs_scrub_progress *progress, int readonly, int is_dev_replace) { struct btrfs_dev_lookup_args args = { .devid = devid }; struct scrub_ctx *sctx; int ret; struct btrfs_device *dev; unsigned int nofs_flag; bool need_commit = false; if (btrfs_fs_closing(fs_info)) return -EAGAIN; /* At mount time we have ensured nodesize is in the range of [4K, 64K]. */ ASSERT(fs_info->nodesize <= BTRFS_STRIPE_LEN); /* * SCRUB_MAX_SECTORS_PER_BLOCK is calculated using the largest possible * value (max nodesize / min sectorsize), thus nodesize should always * be fine. */ ASSERT(fs_info->nodesize <= SCRUB_MAX_SECTORS_PER_BLOCK << fs_info->sectorsize_bits); /* Allocate outside of device_list_mutex */ sctx = scrub_setup_ctx(fs_info, is_dev_replace); if (IS_ERR(sctx)) return PTR_ERR(sctx); ret = scrub_workers_get(fs_info, is_dev_replace); if (ret) goto out_free_ctx; mutex_lock(&fs_info->fs_devices->device_list_mutex); dev = btrfs_find_device(fs_info->fs_devices, &args); if (!dev || (test_bit(BTRFS_DEV_STATE_MISSING, &dev->dev_state) && !is_dev_replace)) { mutex_unlock(&fs_info->fs_devices->device_list_mutex); ret = -ENODEV; goto out; } if (!is_dev_replace && !readonly && !test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) { mutex_unlock(&fs_info->fs_devices->device_list_mutex); btrfs_err_in_rcu(fs_info, "scrub on devid %llu: filesystem on %s is not writable", devid, btrfs_dev_name(dev)); ret = -EROFS; goto out; } mutex_lock(&fs_info->scrub_lock); if (!test_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &dev->dev_state) || test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &dev->dev_state)) { mutex_unlock(&fs_info->scrub_lock); mutex_unlock(&fs_info->fs_devices->device_list_mutex); ret = -EIO; goto out; } down_read(&fs_info->dev_replace.rwsem); if (dev->scrub_ctx || (!is_dev_replace && btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) { up_read(&fs_info->dev_replace.rwsem); mutex_unlock(&fs_info->scrub_lock); mutex_unlock(&fs_info->fs_devices->device_list_mutex); ret = -EINPROGRESS; goto out; } up_read(&fs_info->dev_replace.rwsem); sctx->readonly = readonly; dev->scrub_ctx = sctx; mutex_unlock(&fs_info->fs_devices->device_list_mutex); /* * checking @scrub_pause_req here, we can avoid * race between committing transaction and scrubbing. */ __scrub_blocked_if_needed(fs_info); atomic_inc(&fs_info->scrubs_running); mutex_unlock(&fs_info->scrub_lock); /* * In order to avoid deadlock with reclaim when there is a transaction * trying to pause scrub, make sure we use GFP_NOFS for all the * allocations done at btrfs_scrub_sectors() and scrub_sectors_for_parity() * invoked by our callees. The pausing request is done when the * transaction commit starts, and it blocks the transaction until scrub * is paused (done at specific points at scrub_stripe() or right above * before incrementing fs_info->scrubs_running). */ nofs_flag = memalloc_nofs_save(); if (!is_dev_replace) { u64 old_super_errors; spin_lock(&sctx->stat_lock); old_super_errors = sctx->stat.super_errors; spin_unlock(&sctx->stat_lock); btrfs_info(fs_info, "scrub: started on devid %llu", devid); /* * by holding device list mutex, we can * kick off writing super in log tree sync. */ mutex_lock(&fs_info->fs_devices->device_list_mutex); ret = scrub_supers(sctx, dev); mutex_unlock(&fs_info->fs_devices->device_list_mutex); spin_lock(&sctx->stat_lock); /* * Super block errors found, but we can not commit transaction * at current context, since btrfs_commit_transaction() needs * to pause the current running scrub (hold by ourselves). */ if (sctx->stat.super_errors > old_super_errors && !sctx->readonly) need_commit = true; spin_unlock(&sctx->stat_lock); } if (!ret) ret = scrub_enumerate_chunks(sctx, dev, start, end); memalloc_nofs_restore(nofs_flag); wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); atomic_dec(&fs_info->scrubs_running); wake_up(&fs_info->scrub_pause_wait); wait_event(sctx->list_wait, atomic_read(&sctx->workers_pending) == 0); if (progress) memcpy(progress, &sctx->stat, sizeof(*progress)); if (!is_dev_replace) btrfs_info(fs_info, "scrub: %s on devid %llu with status: %d", ret ? "not finished" : "finished", devid, ret); mutex_lock(&fs_info->scrub_lock); dev->scrub_ctx = NULL; mutex_unlock(&fs_info->scrub_lock); scrub_workers_put(fs_info); scrub_put_ctx(sctx); /* * We found some super block errors before, now try to force a * transaction commit, as scrub has finished. */ if (need_commit) { struct btrfs_trans_handle *trans; trans = btrfs_start_transaction(fs_info->tree_root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); btrfs_err(fs_info, "scrub: failed to start transaction to fix super block errors: %d", ret); return ret; } ret = btrfs_commit_transaction(trans); if (ret < 0) btrfs_err(fs_info, "scrub: failed to commit transaction to fix super block errors: %d", ret); } return ret; out: scrub_workers_put(fs_info); out_free_ctx: scrub_free_ctx(sctx); return ret; } void btrfs_scrub_pause(struct btrfs_fs_info *fs_info) { mutex_lock(&fs_info->scrub_lock); atomic_inc(&fs_info->scrub_pause_req); while (atomic_read(&fs_info->scrubs_paused) != atomic_read(&fs_info->scrubs_running)) { mutex_unlock(&fs_info->scrub_lock); wait_event(fs_info->scrub_pause_wait, atomic_read(&fs_info->scrubs_paused) == atomic_read(&fs_info->scrubs_running)); mutex_lock(&fs_info->scrub_lock); } mutex_unlock(&fs_info->scrub_lock); } void btrfs_scrub_continue(struct btrfs_fs_info *fs_info) { atomic_dec(&fs_info->scrub_pause_req); wake_up(&fs_info->scrub_pause_wait); } int btrfs_scrub_cancel(struct btrfs_fs_info *fs_info) { mutex_lock(&fs_info->scrub_lock); if (!atomic_read(&fs_info->scrubs_running)) { mutex_unlock(&fs_info->scrub_lock); return -ENOTCONN; } atomic_inc(&fs_info->scrub_cancel_req); while (atomic_read(&fs_info->scrubs_running)) { mutex_unlock(&fs_info->scrub_lock); wait_event(fs_info->scrub_pause_wait, atomic_read(&fs_info->scrubs_running) == 0); mutex_lock(&fs_info->scrub_lock); } atomic_dec(&fs_info->scrub_cancel_req); mutex_unlock(&fs_info->scrub_lock); return 0; } int btrfs_scrub_cancel_dev(struct btrfs_device *dev) { struct btrfs_fs_info *fs_info = dev->fs_info; struct scrub_ctx *sctx; mutex_lock(&fs_info->scrub_lock); sctx = dev->scrub_ctx; if (!sctx) { mutex_unlock(&fs_info->scrub_lock); return -ENOTCONN; } atomic_inc(&sctx->cancel_req); while (dev->scrub_ctx) { mutex_unlock(&fs_info->scrub_lock); wait_event(fs_info->scrub_pause_wait, dev->scrub_ctx == NULL); mutex_lock(&fs_info->scrub_lock); } mutex_unlock(&fs_info->scrub_lock); return 0; } int btrfs_scrub_progress(struct btrfs_fs_info *fs_info, u64 devid, struct btrfs_scrub_progress *progress) { struct btrfs_dev_lookup_args args = { .devid = devid }; struct btrfs_device *dev; struct scrub_ctx *sctx = NULL; mutex_lock(&fs_info->fs_devices->device_list_mutex); dev = btrfs_find_device(fs_info->fs_devices, &args); if (dev) sctx = dev->scrub_ctx; if (sctx) memcpy(progress, &sctx->stat, sizeof(*progress)); mutex_unlock(&fs_info->fs_devices->device_list_mutex); return dev ? (sctx ? 0 : -ENOTCONN) : -ENODEV; }