diff options
Diffstat (limited to 'fs/btrfs/scrub.c')
| -rw-r--r-- | fs/btrfs/scrub.c | 668 |
1 files changed, 525 insertions, 143 deletions
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index a8d03d5..ddf2c90 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -17,10 +17,14 @@ */ #include <linux/blkdev.h> +#include <linux/ratelimit.h> #include "ctree.h" #include "volumes.h" #include "disk-io.h" #include "ordered-data.h" +#include "transaction.h" +#include "backref.h" +#include "extent_io.h" /* * This is only the first step towards a full-features scrub. It reads all @@ -29,15 +33,12 @@ * any can be found. * * Future enhancements: - * - To enhance the performance, better read-ahead strategies for the - * extent-tree can be employed. * - In case an unrepairable extent is encountered, track which files are * affected and report them * - In case of a read error on files with nodatasum, map the file and read * the extent to trigger a writeback of the good copy * - track and record media errors, throw out bad devices * - add a mode to also read unallocated space - * - make the prefetch cancellable */ struct scrub_bio; @@ -63,7 +64,7 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix); struct scrub_page { u64 flags; /* extent flags */ u64 generation; - u64 mirror_num; + int mirror_num; int have_csum; u8 csum[BTRFS_CSUM_SIZE]; }; @@ -87,6 +88,7 @@ struct scrub_dev { int first_free; int curr; atomic_t in_flight; + atomic_t fixup_cnt; spinlock_t list_lock; wait_queue_head_t list_wait; u16 csum_size; @@ -100,6 +102,27 @@ struct scrub_dev { spinlock_t stat_lock; }; +struct scrub_fixup_nodatasum { + struct scrub_dev *sdev; + u64 logical; + struct btrfs_root *root; + struct btrfs_work work; + int mirror_num; +}; + +struct scrub_warning { + struct btrfs_path *path; + u64 extent_item_size; + char *scratch_buf; + char *msg_buf; + const char *errstr; + sector_t sector; + u64 logical; + struct btrfs_device *dev; + int msg_bufsize; + int scratch_bufsize; +}; + static void scrub_free_csums(struct scrub_dev *sdev) { while (!list_empty(&sdev->csum_list)) { @@ -175,14 +198,15 @@ struct scrub_dev *scrub_setup_dev(struct btrfs_device *dev) if (i != SCRUB_BIOS_PER_DEV-1) sdev->bios[i]->next_free = i + 1; - else + else sdev->bios[i]->next_free = -1; } sdev->first_free = 0; sdev->curr = -1; atomic_set(&sdev->in_flight, 0); + atomic_set(&sdev->fixup_cnt, 0); atomic_set(&sdev->cancel_req, 0); - sdev->csum_size = btrfs_super_csum_size(&fs_info->super_copy); + sdev->csum_size = btrfs_super_csum_size(fs_info->super_copy); INIT_LIST_HEAD(&sdev->csum_list); spin_lock_init(&sdev->list_lock); @@ -195,24 +219,366 @@ nomem: return ERR_PTR(-ENOMEM); } +static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx) +{ + u64 isize; + u32 nlink; + int ret; + int i; + struct extent_buffer *eb; + struct btrfs_inode_item *inode_item; + struct scrub_warning *swarn = ctx; + struct btrfs_fs_info *fs_info = swarn->dev->dev_root->fs_info; + struct inode_fs_paths *ipath = NULL; + struct btrfs_root *local_root; + struct btrfs_key root_key; + + root_key.objectid = root; + root_key.type = BTRFS_ROOT_ITEM_KEY; + root_key.offset = (u64)-1; + local_root = btrfs_read_fs_root_no_name(fs_info, &root_key); + if (IS_ERR(local_root)) { + ret = PTR_ERR(local_root); + goto err; + } + + ret = inode_item_info(inum, 0, local_root, swarn->path); + if (ret) { + 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); + isize = btrfs_inode_size(eb, inode_item); + nlink = btrfs_inode_nlink(eb, inode_item); + btrfs_release_path(swarn->path); + + ipath = init_ipath(4096, local_root, swarn->path); + if (IS_ERR(ipath)) { + 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) + printk(KERN_WARNING "btrfs: %s at logical %llu on dev " + "%s, sector %llu, root %llu, inode %llu, offset %llu, " + "length %llu, links %u (path: %s)\n", swarn->errstr, + swarn->logical, swarn->dev->name, + (unsigned long long)swarn->sector, root, inum, offset, + min(isize - offset, (u64)PAGE_SIZE), nlink, + (char *)(unsigned long)ipath->fspath->val[i]); + + free_ipath(ipath); + return 0; + +err: + printk(KERN_WARNING "btrfs: %s at logical %llu on dev " + "%s, sector %llu, root %llu, inode %llu, offset %llu: path " + "resolving failed with ret=%d\n", swarn->errstr, + swarn->logical, swarn->dev->name, + (unsigned long long)swarn->sector, root, inum, offset, ret); + + free_ipath(ipath); + return 0; +} + +static void scrub_print_warning(const char *errstr, struct scrub_bio *sbio, + int ix) +{ + struct btrfs_device *dev = sbio->sdev->dev; + struct btrfs_fs_info *fs_info = dev->dev_root->fs_info; + struct btrfs_path *path; + struct btrfs_key found_key; + struct extent_buffer *eb; + struct btrfs_extent_item *ei; + struct scrub_warning swarn; + u32 item_size; + int ret; + u64 ref_root; + u8 ref_level; + unsigned long ptr = 0; + const int bufsize = 4096; + u64 extent_offset; + + path = btrfs_alloc_path(); + + swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS); + swarn.msg_buf = kmalloc(bufsize, GFP_NOFS); + swarn.sector = (sbio->physical + ix * PAGE_SIZE) >> 9; + swarn.logical = sbio->logical + ix * PAGE_SIZE; + swarn.errstr = errstr; + swarn.dev = dev; + swarn.msg_bufsize = bufsize; + swarn.scratch_bufsize = bufsize; + + if (!path || !swarn.scratch_buf || !swarn.msg_buf) + goto out; + + ret = extent_from_logical(fs_info, swarn.logical, path, &found_key); + if (ret < 0) + goto out; + + extent_offset = swarn.logical - found_key.objectid; + 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_nr(eb, path->slots[0]); + + if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK) { + do { + ret = tree_backref_for_extent(&ptr, eb, ei, item_size, + &ref_root, &ref_level); + printk(KERN_WARNING "%s at logical %llu on dev %s, " + "sector %llu: metadata %s (level %d) in tree " + "%llu\n", errstr, swarn.logical, dev->name, + (unsigned long long)swarn.sector, + ref_level ? "node" : "leaf", + ret < 0 ? -1 : ref_level, + ret < 0 ? -1 : ref_root); + } while (ret != 1); + } else { + swarn.path = path; + iterate_extent_inodes(fs_info, path, found_key.objectid, + extent_offset, + scrub_print_warning_inode, &swarn); + } + +out: + btrfs_free_path(path); + kfree(swarn.scratch_buf); + kfree(swarn.msg_buf); +} + +static int scrub_fixup_readpage(u64 inum, u64 offset, u64 root, void *ctx) +{ + struct page *page = NULL; + unsigned long index; + struct scrub_fixup_nodatasum *fixup = ctx; + int ret; + int corrected = 0; + struct btrfs_key key; + struct inode *inode = NULL; + u64 end = offset + PAGE_SIZE - 1; + struct btrfs_root *local_root; + + key.objectid = root; + key.type = BTRFS_ROOT_ITEM_KEY; + key.offset = (u64)-1; + local_root = btrfs_read_fs_root_no_name(fixup->root->fs_info, &key); + if (IS_ERR(local_root)) + return PTR_ERR(local_root); + + key.type = BTRFS_INODE_ITEM_KEY; + key.objectid = inum; + key.offset = 0; + inode = btrfs_iget(fixup->root->fs_info->sb, &key, local_root, NULL); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + index = offset >> PAGE_CACHE_SHIFT; + + page = find_or_create_page(inode->i_mapping, index, GFP_NOFS); + if (!page) { + ret = -ENOMEM; + goto out; + } + + if (PageUptodate(page)) { + struct btrfs_mapping_tree *map_tree; + if (PageDirty(page)) { + /* + * we need to write the data to the defect sector. the + * data that was in that sector is not in memory, + * because the page was modified. we must not write the + * modified page to that sector. + * + * TODO: what could be done here: wait for the delalloc + * runner to write out that page (might involve + * COW) and see whether the sector is still + * referenced afterwards. + * + * For the meantime, we'll treat this error + * incorrectable, although there is a chance that a + * later scrub will find the bad sector again and that + * there's no dirty page in memory, then. + */ + ret = -EIO; + goto out; + } + map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree; + ret = repair_io_failure(map_tree, offset, PAGE_SIZE, + fixup->logical, page, + fixup->mirror_num); + unlock_page(page); + corrected = !ret; + } else { + /* + * we need to get good data first. the general readpage path + * will call repair_io_failure for us, we just have to make + * sure we read the bad mirror. + */ + ret = set_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + if (ret) { + /* set_extent_bits should give proper error */ + WARN_ON(ret > 0); + if (ret > 0) + ret = -EFAULT; + goto out; + } + + ret = extent_read_full_page(&BTRFS_I(inode)->io_tree, page, + btrfs_get_extent, + fixup->mirror_num); + wait_on_page_locked(page); + + corrected = !test_range_bit(&BTRFS_I(inode)->io_tree, offset, + end, EXTENT_DAMAGED, 0, NULL); + if (!corrected) + clear_extent_bits(&BTRFS_I(inode)->io_tree, offset, end, + EXTENT_DAMAGED, GFP_NOFS); + } + +out: + if (page) + put_page(page); + if (inode) + iput(inode); + + if (ret < 0) + return ret; + + if (ret == 0 && corrected) { + /* + * we only need to call readpage for one of the inodes belonging + * to this extent. so make iterate_extent_inodes stop + */ + return 1; + } + + return -EIO; +} + +static void scrub_fixup_nodatasum(struct btrfs_work *work) +{ + int ret; + struct scrub_fixup_nodatasum *fixup; + struct scrub_dev *sdev; + struct btrfs_trans_handle *trans = NULL; + struct btrfs_fs_info *fs_info; + struct btrfs_path *path; + int uncorrectable = 0; + + fixup = container_of(work, struct scrub_fixup_nodatasum, work); + sdev = fixup->sdev; + fs_info = fixup->root->fs_info; + + path = btrfs_alloc_path(); + if (!path) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.malloc_errors; + spin_unlock(&sdev->stat_lock); + uncorrectable = 1; + goto out; + } + + trans = btrfs_join_transaction(fixup->root); + if (IS_ERR(trans)) { + uncorrectable = 1; + goto out; + } + + /* + * the idea is to trigger a regular read through the standard path. we + * read a page from the (failed) logical address by specifying the + * corresponding copynum of the failed sector. thus, that readpage is + * expected to fail. + * that is the point where on-the-fly error correction will kick in + * (once it's finished) and rewrite the failed sector if a good copy + * can be found. + */ + ret = iterate_inodes_from_logical(fixup->logical, fixup->root->fs_info, + path, scrub_fixup_readpage, + fixup); + if (ret < 0) { + uncorrectable = 1; + goto out; + } + WARN_ON(ret != 1); + + spin_lock(&sdev->stat_lock); + ++sdev->stat.corrected_errors; + spin_unlock(&sdev->stat_lock); + +out: + if (trans && !IS_ERR(trans)) + btrfs_end_transaction(trans, fixup->root); + if (uncorrectable) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.uncorrectable_errors; + spin_unlock(&sdev->stat_lock); + printk_ratelimited(KERN_ERR "btrfs: unable to fixup " + "(nodatasum) error at logical %llu\n", + fixup->logical); + } + + btrfs_free_path(path); + kfree(fixup); + + /* see caller why we're pretending to be paused in the scrub counters */ + mutex_lock(&fs_info->scrub_lock); + atomic_dec(&fs_info->scrubs_running); + atomic_dec(&fs_info->scrubs_paused); + mutex_unlock(&fs_info->scrub_lock); + atomic_dec(&sdev->fixup_cnt); + wake_up(&fs_info->scrub_pause_wait); + wake_up(&sdev->list_wait); +} + /* * scrub_recheck_error gets called when either verification of the page * failed or the bio failed to read, e.g. with EIO. In the latter case, * recheck_error gets called for every page in the bio, even though only * one may be bad */ -static void scrub_recheck_error(struct scrub_bio *sbio, int ix) +static int scrub_recheck_error(struct scrub_bio *sbio, int ix) { + struct scrub_dev *sdev = sbio->sdev; + u64 sector = (sbio->physical + ix * PAGE_SIZE) >> 9; + static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, + DEFAULT_RATELIMIT_BURST); + if (sbio->err) { - if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, - (sbio->physical + ix * PAGE_SIZE) >> 9, + if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, sector, sbio->bio->bi_io_vec[ix].bv_page) == 0) { if (scrub_fixup_check(sbio, ix) == 0) - return; + return 0; } + if (__ratelimit(&_rs)) + scrub_print_warning("i/o error", sbio, ix); + } else { + if (__ratelimit(&_rs)) + scrub_print_warning("checksum error", sbio, ix); } + spin_lock(&sdev->stat_lock); + ++sdev->stat.read_errors; + spin_unlock(&sdev->stat_lock); + scrub_fixup(sbio, ix); + return 1; } static int scrub_fixup_check(struct scrub_bio *sbio, int ix) @@ -250,7 +616,8 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) struct scrub_dev *sdev = sbio->sdev; struct btrfs_fs_info *fs_info = sdev->dev->dev_root->fs_info; struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree; - struct btrfs_multi_bio *multi = NULL; + struct btrfs_bio *bbio = NULL; + struct scrub_fixup_nodatasum *fixup; u64 logical = sbio->logical + ix * PAGE_SIZE; u64 length; int i; @@ -259,38 +626,57 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) if ((sbio->spag[ix].flags & BTRFS_EXTENT_FLAG_DATA) && (sbio->spag[ix].have_csum == 0)) { + fixup = kzalloc(sizeof(*fixup), GFP_NOFS); + if (!fixup) + goto uncorrectable; + fixup->sdev = sdev; + fixup->logical = logical; + fixup->root = fs_info->extent_root; + fixup->mirror_num = sbio->spag[ix].mirror_num; /* - * nodatasum, don't try to fix anything - * FIXME: we can do better, open the inode and trigger a - * writeback + * increment scrubs_running to prevent cancel requests from + * completing as long as a fixup worker is running. we must also + * increment scrubs_paused to prevent deadlocking on pause + * requests used for transactions commits (as the worker uses a + * transaction context). it is safe to regard the fixup worker + * as paused for all matters practical. effectively, we only + * avoid cancellation requests from completing. */ - goto uncorrectable; + mutex_lock(&fs_info->scrub_lock); + atomic_inc(&fs_info->scrubs_running); + atomic_inc(&fs_info->scrubs_paused); + mutex_unlock(&fs_info->scrub_lock); + atomic_inc(&sdev->fixup_cnt); + fixup->work.func = scrub_fixup_nodatasum; + btrfs_queue_worker(&fs_info->scrub_workers, &fixup->work); + return; } length = PAGE_SIZE; ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length, - &multi, 0); - if (ret || !multi || length < PAGE_SIZE) { + &bbio, 0); + if (ret || !bbio || length < PAGE_SIZE) { printk(KERN_ERR "scrub_fixup: btrfs_map_block failed us for %llu\n", (unsigned long long)logical); WARN_ON(1); + kfree(bbio); return; } - if (multi->num_stripes == 1) + if (bbio->num_stripes == 1) /* there aren't any replicas */ goto uncorrectable; /* * first find a good copy */ - for (i = 0; i < multi->num_stripes; ++i) { - if (i == sbio->spag[ix].mirror_num) + for (i = 0; i < bbio->num_stripes; ++i) { + if (i + 1 == sbio->spag[ix].mirror_num) continue; - if (scrub_fixup_io(READ, multi->stripes[i].dev->bdev, - multi->stripes[i].physical >> 9, + if (scrub_fixup_io(READ, bbio->stripes[i].dev->bdev, + bbio->stripes[i].physical >> 9, sbio->bio->bi_io_vec[ix].bv_page)) { /* I/O-error, this is not a good copy */ continue; @@ -299,7 +685,7 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) if (scrub_fixup_check(sbio, ix) == 0) break; } - if (i == multi->num_stripes) + if (i == bbio->num_stripes) goto uncorrectable; if (!sdev->readonly) { @@ -314,25 +700,23 @@ static void scrub_fixup(struct scrub_bio *sbio, int ix) } } - kfree(multi); + kfree(bbio); spin_lock(&sdev->stat_lock); ++sdev->stat.corrected_errors; spin_unlock(&sdev->stat_lock); - if (printk_ratelimit()) - printk(KERN_ERR "btrfs: fixed up at %llu\n", - (unsigned long long)logical); + printk_ratelimited(KERN_ERR "btrfs: fixed up error at logical %llu\n", + (unsigned long long)logical); return; uncorrectable: - kfree(multi); + kfree(bbio); spin_lock(&sdev->stat_lock); ++sdev->stat.uncorrectable_errors; spin_unlock(&sdev->stat_lock); - if (printk_ratelimit()) - printk(KERN_ERR "btrfs: unable to fixup at %llu\n", - (unsigned long long)logical); + printk_ratelimited(KERN_ERR "btrfs: unable to fixup (regular) error at " + "logical %llu\n", (unsigned long long)logical); } static int scrub_fixup_io(int rw, struct block_device *bdev, sector_t sector, @@ -382,8 +766,14 @@ static void scrub_checksum(struct btrfs_work *work) int ret; if (sbio->err) { + ret = 0; for (i = 0; i < sbio->count; ++i) - scrub_recheck_error(sbio, i); + ret |= scrub_recheck_error(sbio, i); + if (!ret) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.unverified_errors; + spin_unlock(&sdev->stat_lock); + } sbio->bio->bi_flags &= ~(BIO_POOL_MASK - 1); sbio->bio->bi_flags |= 1 << BIO_UPTODATE; @@ -396,10 +786,6 @@ static void scrub_checksum(struct btrfs_work *work) bi->bv_offset = 0; bi->bv_len = PAGE_SIZE; } - - spin_lock(&sdev->stat_lock); - ++sdev->stat.read_errors; - spin_unlock(&sdev->stat_lock); goto out; } for (i = 0; i < sbio->count; ++i) { @@ -420,8 +806,14 @@ static void scrub_checksum(struct btrfs_work *work) WARN_ON(1); } kunmap_atomic(buffer, KM_USER0); - if (ret) - scrub_recheck_error(sbio, i); + if (ret) { + ret = scrub_recheck_error(sbio, i); + if (!ret) { + spin_lock(&sdev->stat_lock); + ++sdev->stat.unverified_errors; + spin_unlock(&sdev->stat_lock); + } + } } out: @@ -557,57 +949,27 @@ static int scrub_checksum_super(struct scrub_bio *sbio, void *buffer) static int scrub_submit(struct scrub_dev *sdev) { struct scrub_bio *sbio; - struct bio *bio; - int i; if (sdev->curr == -1) return 0; sbio = sdev->bios[sdev->curr]; - - bio = bio_alloc(GFP_NOFS, sbio->count); - if (!bio) - goto nomem; - - bio->bi_private = sbio; - bio->bi_end_io = scrub_bio_end_io; - bio->bi_bdev = sdev->dev->bdev; - bio->bi_sector = sbio->physical >> 9; - - for (i = 0; i < sbio->count; ++i) { - struct page *page; - int ret; - - page = alloc_page(GFP_NOFS); - if (!page) - goto nomem; - - ret = bio_add_page(bio, page, PAGE_SIZE, 0); - if (!ret) { - __free_page(page); - goto nomem; - } - } - sbio->err = 0; sdev->curr = -1; atomic_inc(&sdev->in_flight); - submit_bio(READ, bio); + submit_bio(READ, sbio->bio); return 0; - -nomem: - scrub_free_bio(bio); - - return -ENOMEM; } static int scrub_page(struct scrub_dev *sdev, u64 logical, u64 len, - u64 physical, u64 flags, u64 gen, u64 mirror_num, + u64 physical, u64 flags, u64 gen, int mirror_num, u8 *csum, int force) { struct scrub_bio *sbio; + struct page *page; + int ret; again: /* @@ -628,12 +990,22 @@ again: } sbio = sdev->bios[sdev->curr]; if (sbio->count == 0) { + struct bio *bio; + sbio->physical = physical; sbio->logical = logical; + bio = bio_alloc(GFP_NOFS, SCRUB_PAGES_PER_BIO); + if (!bio) + return -ENOMEM; + + bio->bi_private = sbio; + bio->bi_end_io = scrub_bio_end_io; + bio->bi_bdev = sdev->dev->bdev; + bio->bi_sector = sbio->physical >> 9; + sbio->err = 0; + sbio->bio = bio; } else if (sbio->physical + sbio->count * PAGE_SIZE != physical || sbio->logical + sbio->count * PAGE_SIZE != logical) { - int ret; - ret = scrub_submit(sdev); if (ret) return ret; @@ -643,6 +1015,20 @@ again: sbio->spag[sbio->count].generation = gen; sbio->spag[sbio->count].have_csum = 0; sbio->spag[sbio->count].mirror_num = mirror_num; + + page = alloc_page(GFP_NOFS); + if (!page) + return -ENOMEM; + + ret = bio_add_page(sbio->bio, page, PAGE_SIZE, 0); + if (!ret) { + __free_page(page); + ret = scrub_submit(sdev); + if (ret) + return ret; + goto again; + } + if (csum) { sbio->spag[sbio->count].have_csum = 1; memcpy(sbio->spag[sbio->count].csum, csum, sdev->csum_size); @@ -701,7 +1087,7 @@ static int scrub_find_csum(struct scrub_dev *sdev, u64 logical, u64 len, /* scrub extent tries to collect up to 64 kB for each bio */ static int scrub_extent(struct scrub_dev *sdev, u64 logical, u64 len, - u64 physical, u64 flags, u64 gen, u64 mirror_num) + u64 physical, u64 flags, u64 gen, int mirror_num) { int ret; u8 csum[BTRFS_CSUM_SIZE]; @@ -741,13 +1127,16 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, int slot; int i; u64 nstripes; - int start_stripe; struct extent_buffer *l; struct btrfs_key key; u64 physical; u64 logical; u64 generation; - u64 mirror_num; + int mirror_num; + struct reada_control *reada1; + struct reada_control *reada2; + struct btrfs_key key_start; + struct btrfs_key key_end; u64 increment = map->stripe_len; u64 offset; @@ -758,102 +1147,88 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev, if (map->type & BTRFS_BLOCK_GROUP_RAID0) { offset = map->stripe_len * num; increment = map->stripe_len * map->num_stripes; - mirror_num = 0; + mirror_num = 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID10) { int factor = map->num_stripes / map->sub_stripes; offset = map->stripe_len * (num / map->sub_stripes); increment = map->stripe_len * factor; - mirror_num = num % map->sub_stripes; + mirror_num = num % map->sub_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { increment = map->stripe_len; - mirror_num = num % map->num_stripes; + mirror_num = num % map->num_stripes + 1; } else if (map->type & BTRFS_BLOCK_GROUP_DUP) { increment = map->stripe_len; - mirror_num = num % map->num_stripes; + mirror_num = num % map->num_stripes + 1; } else { increment = map->stripe_len; - mirror_num = 0; + mirror_num = 1; } path = btrfs_alloc_path(); if (!path) return -ENOMEM; - path->reada = 2; path->search_commit_root = 1; path->skip_locking = 1; /* - * find all extents for each stripe and just read them to get - * them into the page cache - * FIXME: we can do better. build a more intelligent prefetching + * trigger the readahead for extent tree csum tree and wait for + * completion. During readahead, the scrub is officially paused + * to not hold off transaction commits */ logical = base + offset; - physical = map->stripes[num].physical; - ret = 0; - for (i = 0; i < nstripes; ++i) { - key.objectid = logical; - key.type = BTRFS_EXTENT_ITEM_KEY; - key.offset = (u64)0; - - ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); - if (ret < 0) - goto out_noplug; - /* - * we might miss half an extent here, but that doesn't matter, - * as it's only the prefetch - */ - while (1) { - l = path->nodes[0]; - slot = path->slots[0]; - if (slot >= btrfs_header_nritems(l)) { - ret = btrfs_next_leaf(root, path); - if (ret == 0) - continue; - if (ret < 0) - goto out_noplug; - - break; - } - btrfs_item_key_to_cpu(l, &key, slot); + wait_event(sdev->list_wait, + atomic_read(&sdev->in_flight) == 0); + atomic_inc(&fs_info->scrubs_paused); + wake_up(&fs_info->scrub_pause_wait); - if (key.objectid >= logical + map->stripe_len) - break; + /* FIXME it might be better to start readahead at commit root */ + key_start.objectid = logical; + key_start.type = BTRFS_EXTENT_ITEM_KEY; + key_start.offset = (u64)0; + key_end.objectid = base + offset + nstripes * increment; + key_end.type = BTRFS_EXTENT_ITEM_KEY; + key_end.offset = (u64)0; + reada1 = btrfs_reada_add(root, &key_start, &key_end); + + key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID; + key_start.type = BTRFS_EXTENT_CSUM_KEY; + key_start.offset = logical; + key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID; + key_end.type = BTRFS_EXTENT_CSUM_KEY; + key_end.offset = base + offset + nstripes * increment; + reada2 = btrfs_reada_add(csum_root, &key_start, &key_end); + + if (!IS_ERR(reada1)) + btrfs_reada_wait(reada1); + if (!IS_ERR(reada2)) + btrfs_reada_wait(reada2); - path->slots[0]++; - } - btrfs_release_path(path); - logical += increment; - physical += map->stripe_len; - cond_resched(); + mutex_lock(&fs_info->scrub_lock); + 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); } + atomic_dec(&fs_info->scrubs_paused); + mutex_unlock(&fs_info->scrub_lock); + wake_up(&fs_info->scrub_pause_wait); /* * collect all data csums for the stripe to avoid seeking during * the scrub. This might currently (crc32) end up to be about 1MB */ - start_stripe = 0; blk_start_plug(&plug); -again: - logical = base + offset + start_stripe * increment; - for (i = start_stripe; i < nstripes; ++i) { - ret = btrfs_lookup_csums_range(csum_root, logical, - logical + map->stripe_len - 1, - &sdev->csum_list, 1); - if (ret) - goto out; - logical += increment; - cond_resched(); - } /* * now find all extents for each stripe and scrub them */ - logical = base + offset + start_stripe * increment; - physical = map->stripes[num].physical + start_stripe * map->stripe_len; + logical = base + offset; + physical = map->stripes[num].physical; ret = 0; - for (i = start_stripe; i < nstripes; ++i) { + for (i = 0; i < nstripes; ++i) { /* * canceled? */ @@ -882,11 +1257,14 @@ again: atomic_dec(&fs_info->scrubs_paused); mutex_unlock(&fs_info->scrub_lock); wake_up(&fs_info->scrub_pause_wait); - scrub_free_csums(sdev); - start_stripe = i; - goto again; } + ret = btrfs_lookup_csums_range(csum_root, logical, + logical + map->stripe_len - 1, + &sdev->csum_list, 1); + if (ret) + goto out; + key.objectid = logical; key.type = BTRFS_EXTENT_ITEM_KEY; key.offset = (u64)0; @@ -982,7 +1360,6 @@ next: out: blk_finish_plug(&plug); -out_noplug: btrfs_free_path(path); return ret < 0 ? ret : 0; } @@ -1158,18 +1535,22 @@ static noinline_for_stack int scrub_supers(struct scrub_dev *sdev) static noinline_for_stack int scrub_workers_get(struct btrfs_root *root) { struct btrfs_fs_info *fs_info = root->fs_info; + int ret = 0; mutex_lock(&fs_info->scrub_lock); if (fs_info->scrub_workers_refcnt == 0) { btrfs_init_workers(&fs_info->scrub_workers, "scrub", fs_info->thread_pool_size, &fs_info->generic_worker); fs_info->scrub_workers.idle_thresh = 4; - btrfs_start_workers(&fs_info->scrub_workers, 1); + ret = btrfs_start_workers(&fs_info->scrub_workers); + if (ret) + goto out; } ++fs_info->scrub_workers_refcnt; +out: mutex_unlock(&fs_info->scrub_lock); - return 0; + return ret; } static noinline_for_stack void scrub_workers_put(struct btrfs_root *root) @@ -1253,10 +1634,11 @@ int btrfs_scrub_dev(struct btrfs_root *root, u64 devid, u64 start, u64 end, ret = scrub_enumerate_chunks(sdev, start, end); wait_event(sdev->list_wait, atomic_read(&sdev->in_flight) == 0); - atomic_dec(&fs_info->scrubs_running); wake_up(&fs_info->scrub_pause_wait); + wait_event(sdev->list_wait, atomic_read(&sdev->fixup_cnt) == 0); + if (progress) memcpy(progress, &sdev->stat, sizeof(*progress)); |