| /* |
| * Copyright (C) 2011, 2012 STRATO. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public |
| * License v2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public |
| * License along with this program; if not, write to the |
| * Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| * Boston, MA 021110-1307, USA. |
| */ |
| |
| #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" |
| #include "dev-replace.h" |
| #include "check-integrity.h" |
| #include "rcu-string.h" |
| #include "raid56.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 two values configure an upper limit for the number |
| * of (dynamically allocated) pages that are added to a bio. |
| */ |
| #define SCRUB_PAGES_PER_RD_BIO 32 /* 128k per bio */ |
| #define SCRUB_PAGES_PER_WR_BIO 32 /* 128k per bio */ |
| #define SCRUB_BIOS_PER_SCTX 64 /* 8MB per device in flight */ |
| |
| /* |
| * the following value times PAGE_SIZE needs to be large enough to match the |
| * largest node/leaf/sector size that shall be supported. |
| * Values larger than BTRFS_STRIPE_LEN are not supported. |
| */ |
| #define SCRUB_MAX_PAGES_PER_BLOCK 16 /* 64k per node/leaf/sector */ |
| |
| struct scrub_page { |
| struct scrub_block *sblock; |
| struct page *page; |
| struct btrfs_device *dev; |
| u64 flags; /* extent flags */ |
| u64 generation; |
| u64 logical; |
| u64 physical; |
| u64 physical_for_dev_replace; |
| atomic_t ref_count; |
| struct { |
| unsigned int mirror_num:8; |
| unsigned int have_csum:1; |
| unsigned int io_error:1; |
| }; |
| u8 csum[BTRFS_CSUM_SIZE]; |
| }; |
| |
| struct scrub_bio { |
| int index; |
| struct scrub_ctx *sctx; |
| struct btrfs_device *dev; |
| struct bio *bio; |
| int err; |
| u64 logical; |
| u64 physical; |
| #if SCRUB_PAGES_PER_WR_BIO >= SCRUB_PAGES_PER_RD_BIO |
| struct scrub_page *pagev[SCRUB_PAGES_PER_WR_BIO]; |
| #else |
| struct scrub_page *pagev[SCRUB_PAGES_PER_RD_BIO]; |
| #endif |
| int page_count; |
| int next_free; |
| struct btrfs_work work; |
| }; |
| |
| struct scrub_block { |
| struct scrub_page *pagev[SCRUB_MAX_PAGES_PER_BLOCK]; |
| int page_count; |
| atomic_t outstanding_pages; |
| atomic_t ref_count; /* free mem on transition to zero */ |
| struct scrub_ctx *sctx; |
| 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 */ |
| }; |
| }; |
| |
| struct scrub_wr_ctx { |
| struct scrub_bio *wr_curr_bio; |
| struct btrfs_device *tgtdev; |
| int pages_per_wr_bio; /* <= SCRUB_PAGES_PER_WR_BIO */ |
| atomic_t flush_all_writes; |
| struct mutex wr_lock; |
| }; |
| |
| struct scrub_ctx { |
| struct scrub_bio *bios[SCRUB_BIOS_PER_SCTX]; |
| struct btrfs_root *dev_root; |
| int first_free; |
| int curr; |
| atomic_t bios_in_flight; |
| atomic_t workers_pending; |
| spinlock_t list_lock; |
| wait_queue_head_t list_wait; |
| u16 csum_size; |
| struct list_head csum_list; |
| atomic_t cancel_req; |
| int readonly; |
| int pages_per_rd_bio; |
| u32 sectorsize; |
| u32 nodesize; |
| u32 leafsize; |
| |
| int is_dev_replace; |
| struct scrub_wr_ctx wr_ctx; |
| |
| /* |
| * statistics |
| */ |
| struct btrfs_scrub_progress stat; |
| spinlock_t stat_lock; |
| }; |
| |
| struct scrub_fixup_nodatasum { |
| struct scrub_ctx *sctx; |
| struct btrfs_device *dev; |
| u64 logical; |
| struct btrfs_root *root; |
| struct btrfs_work work; |
| int mirror_num; |
| }; |
| |
| struct scrub_nocow_inode { |
| u64 inum; |
| u64 offset; |
| u64 root; |
| struct list_head list; |
| }; |
| |
| struct scrub_copy_nocow_ctx { |
| struct scrub_ctx *sctx; |
| u64 logical; |
| u64 len; |
| int mirror_num; |
| u64 physical_for_dev_replace; |
| struct list_head inodes; |
| struct btrfs_work work; |
| }; |
| |
| 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_pending_bio_inc(struct scrub_ctx *sctx); |
| static void scrub_pending_bio_dec(struct scrub_ctx *sctx); |
| static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx); |
| static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx); |
| static int scrub_handle_errored_block(struct scrub_block *sblock_to_check); |
| static int scrub_setup_recheck_block(struct scrub_ctx *sctx, |
| struct btrfs_fs_info *fs_info, |
| struct scrub_block *original_sblock, |
| u64 length, u64 logical, |
| struct scrub_block *sblocks_for_recheck); |
| static void scrub_recheck_block(struct btrfs_fs_info *fs_info, |
| struct scrub_block *sblock, int is_metadata, |
| int have_csum, u8 *csum, u64 generation, |
| u16 csum_size); |
| static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info, |
| struct scrub_block *sblock, |
| int is_metadata, int have_csum, |
| const u8 *csum, u64 generation, |
| u16 csum_size); |
| static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, |
| struct scrub_block *sblock_good, |
| int force_write); |
| static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad, |
| struct scrub_block *sblock_good, |
| int page_num, int force_write); |
| static void scrub_write_block_to_dev_replace(struct scrub_block *sblock); |
| static int scrub_write_page_to_dev_replace(struct scrub_block *sblock, |
| int page_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_get(struct scrub_block *sblock); |
| static void scrub_block_put(struct scrub_block *sblock); |
| static void scrub_page_get(struct scrub_page *spage); |
| static void scrub_page_put(struct scrub_page *spage); |
| static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx, |
| struct scrub_page *spage); |
| static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len, |
| u64 physical, struct btrfs_device *dev, u64 flags, |
| u64 gen, int mirror_num, u8 *csum, int force, |
| u64 physical_for_dev_replace); |
| static void scrub_bio_end_io(struct bio *bio, int err); |
| static void scrub_bio_end_io_worker(struct btrfs_work *work); |
| static void scrub_block_complete(struct scrub_block *sblock); |
| static void scrub_remap_extent(struct btrfs_fs_info *fs_info, |
| u64 extent_logical, u64 extent_len, |
| u64 *extent_physical, |
| struct btrfs_device **extent_dev, |
| int *extent_mirror_num); |
| static int scrub_setup_wr_ctx(struct scrub_ctx *sctx, |
| struct scrub_wr_ctx *wr_ctx, |
| struct btrfs_fs_info *fs_info, |
| struct btrfs_device *dev, |
| int is_dev_replace); |
| static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx); |
| static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx, |
| struct scrub_page *spage); |
| static void scrub_wr_submit(struct scrub_ctx *sctx); |
| static void scrub_wr_bio_end_io(struct bio *bio, int err); |
| static void scrub_wr_bio_end_io_worker(struct btrfs_work *work); |
| static int write_page_nocow(struct scrub_ctx *sctx, |
| u64 physical_for_dev_replace, struct page *page); |
| static int copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root, |
| struct scrub_copy_nocow_ctx *ctx); |
| static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, u64 len, |
| int mirror_num, u64 physical_for_dev_replace); |
| static void copy_nocow_pages_worker(struct btrfs_work *work); |
| static void __scrub_blocked_if_needed(struct btrfs_fs_info *fs_info); |
| static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info); |
| |
| |
| static void scrub_pending_bio_inc(struct scrub_ctx *sctx) |
| { |
| 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); |
| } |
| |
| 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_blocked_if_needed(struct btrfs_fs_info *fs_info) |
| { |
| atomic_inc(&fs_info->scrubs_paused); |
| wake_up(&fs_info->scrub_pause_wait); |
| |
| 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); |
| } |
| |
| /* |
| * used for workers that require transaction commits (i.e., for the |
| * NOCOW case) |
| */ |
| static void scrub_pending_trans_workers_inc(struct scrub_ctx *sctx) |
| { |
| struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info; |
| |
| /* |
| * increment scrubs_running to prevent cancel requests from |
| * completing as long as a 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 worker |
| * as paused for all matters practical. effectively, we only |
| * avoid cancellation requests from completing. |
| */ |
| mutex_lock(&fs_info->scrub_lock); |
| atomic_inc(&fs_info->scrubs_running); |
| atomic_inc(&fs_info->scrubs_paused); |
| mutex_unlock(&fs_info->scrub_lock); |
| |
| /* |
| * check if @scrubs_running=@scrubs_paused condition |
| * inside wait_event() is not an atomic operation. |
| * which means we may inc/dec @scrub_running/paused |
| * at any time. Let's wake up @scrub_pause_wait as |
| * much as we can to let commit transaction blocked less. |
| */ |
| wake_up(&fs_info->scrub_pause_wait); |
| |
| atomic_inc(&sctx->workers_pending); |
| } |
| |
| /* used for workers that require transaction commits */ |
| static void scrub_pending_trans_workers_dec(struct scrub_ctx *sctx) |
| { |
| struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info; |
| |
| /* |
| * see scrub_pending_trans_workers_inc() 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(&sctx->workers_pending); |
| wake_up(&fs_info->scrub_pause_wait); |
| wake_up(&sctx->list_wait); |
| } |
| |
| 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; |
| |
| scrub_free_wr_ctx(&sctx->wr_ctx); |
| |
| /* this can happen when scrub is cancelled */ |
| if (sctx->curr != -1) { |
| struct scrub_bio *sbio = sctx->bios[sctx->curr]; |
| |
| for (i = 0; i < sbio->page_count; i++) { |
| WARN_ON(!sbio->pagev[i]->page); |
| scrub_block_put(sbio->pagev[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); |
| } |
| |
| scrub_free_csums(sctx); |
| kfree(sctx); |
| } |
| |
| static noinline_for_stack |
| struct scrub_ctx *scrub_setup_ctx(struct btrfs_device *dev, int is_dev_replace) |
| { |
| struct scrub_ctx *sctx; |
| int i; |
| struct btrfs_fs_info *fs_info = dev->dev_root->fs_info; |
| int pages_per_rd_bio; |
| int ret; |
| |
| /* |
| * the setting of pages_per_rd_bio is correct for scrub but might |
| * be wrong for the dev_replace code where we might read from |
| * different devices in the initial huge bios. However, that |
| * code is able to correctly handle the case when adding a page |
| * to a bio fails. |
| */ |
| if (dev->bdev) |
| pages_per_rd_bio = min_t(int, SCRUB_PAGES_PER_RD_BIO, |
| bio_get_nr_vecs(dev->bdev)); |
| else |
| pages_per_rd_bio = SCRUB_PAGES_PER_RD_BIO; |
| sctx = kzalloc(sizeof(*sctx), GFP_NOFS); |
| if (!sctx) |
| goto nomem; |
| sctx->is_dev_replace = is_dev_replace; |
| sctx->pages_per_rd_bio = pages_per_rd_bio; |
| sctx->curr = -1; |
| sctx->dev_root = dev->dev_root; |
| for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) { |
| struct scrub_bio *sbio; |
| |
| sbio = kzalloc(sizeof(*sbio), GFP_NOFS); |
| if (!sbio) |
| goto nomem; |
| sctx->bios[i] = sbio; |
| |
| sbio->index = i; |
| sbio->sctx = sctx; |
| sbio->page_count = 0; |
| btrfs_init_work(&sbio->work, scrub_bio_end_io_worker, |
| NULL, NULL); |
| |
| if (i != SCRUB_BIOS_PER_SCTX - 1) |
| sctx->bios[i]->next_free = i + 1; |
| else |
| sctx->bios[i]->next_free = -1; |
| } |
| sctx->first_free = 0; |
| sctx->nodesize = dev->dev_root->nodesize; |
| sctx->leafsize = dev->dev_root->leafsize; |
| sctx->sectorsize = dev->dev_root->sectorsize; |
| atomic_set(&sctx->bios_in_flight, 0); |
| atomic_set(&sctx->workers_pending, 0); |
| atomic_set(&sctx->cancel_req, 0); |
| sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy); |
| INIT_LIST_HEAD(&sctx->csum_list); |
| |
| spin_lock_init(&sctx->list_lock); |
| spin_lock_init(&sctx->stat_lock); |
| init_waitqueue_head(&sctx->list_wait); |
| |
| ret = scrub_setup_wr_ctx(sctx, &sctx->wr_ctx, fs_info, |
| fs_info->dev_replace.tgtdev, is_dev_replace); |
| if (ret) { |
| scrub_free_ctx(sctx); |
| return ERR_PTR(ret); |
| } |
| return sctx; |
| |
| nomem: |
| scrub_free_ctx(sctx); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, |
| void *warn_ctx) |
| { |
| u64 isize; |
| u32 nlink; |
| int ret; |
| int i; |
| struct extent_buffer *eb; |
| struct btrfs_inode_item *inode_item; |
| struct scrub_warning *swarn = warn_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_in_rcu(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, rcu_str_deref(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_in_rcu(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, rcu_str_deref(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_block *sblock) |
| { |
| struct btrfs_device *dev; |
| struct btrfs_fs_info *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 extent_item_pos; |
| u64 flags = 0; |
| u64 ref_root; |
| u32 item_size; |
| u8 ref_level; |
| const int bufsize = 4096; |
| int ret; |
| |
| WARN_ON(sblock->page_count < 1); |
| dev = sblock->pagev[0]->dev; |
| fs_info = sblock->sctx->dev_root->fs_info; |
| |
| path = btrfs_alloc_path(); |
| |
| swarn.scratch_buf = kmalloc(bufsize, GFP_NOFS); |
| swarn.msg_buf = kmalloc(bufsize, GFP_NOFS); |
| swarn.sector = (sblock->pagev[0]->physical) >> 9; |
| swarn.logical = sblock->pagev[0]->logical; |
| swarn.errstr = errstr; |
| swarn.dev = NULL; |
| 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, |
| &flags); |
| if (ret < 0) |
| goto out; |
| |
| extent_item_pos = 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 (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { |
| do { |
| ret = tree_backref_for_extent(&ptr, eb, &found_key, ei, |
| item_size, &ref_root, |
| &ref_level); |
| printk_in_rcu(KERN_WARNING |
| "BTRFS: %s at logical %llu on dev %s, " |
| "sector %llu: metadata %s (level %d) in tree " |
| "%llu\n", errstr, swarn.logical, |
| rcu_str_deref(dev->name), |
| (unsigned long long)swarn.sector, |
| ref_level ? "node" : "leaf", |
| ret < 0 ? -1 : ref_level, |
| ret < 0 ? -1 : ref_root); |
| } while (ret != 1); |
| btrfs_release_path(path); |
| } else { |
| btrfs_release_path(path); |
| swarn.path = path; |
| swarn.dev = dev; |
| iterate_extent_inodes(fs_info, found_key.objectid, |
| extent_item_pos, 1, |
| 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 *fixup_ctx) |
| { |
| struct page *page = NULL; |
| unsigned long index; |
| struct scrub_fixup_nodatasum *fixup = fixup_ctx; |
| int ret; |
| int corrected = 0; |
| struct btrfs_key key; |
| struct inode *inode = NULL; |
| struct btrfs_fs_info *fs_info; |
| u64 end = offset + PAGE_SIZE - 1; |
| struct btrfs_root *local_root; |
| int srcu_index; |
| |
| key.objectid = root; |
| key.type = BTRFS_ROOT_ITEM_KEY; |
| key.offset = (u64)-1; |
| |
| fs_info = fixup->root->fs_info; |
| srcu_index = srcu_read_lock(&fs_info->subvol_srcu); |
| |
| local_root = btrfs_read_fs_root_no_name(fs_info, &key); |
| if (IS_ERR(local_root)) { |
| srcu_read_unlock(&fs_info->subvol_srcu, srcu_index); |
| return PTR_ERR(local_root); |
| } |
| |
| key.type = BTRFS_INODE_ITEM_KEY; |
| key.objectid = inum; |
| key.offset = 0; |
| inode = btrfs_iget(fs_info->sb, &key, local_root, NULL); |
| srcu_read_unlock(&fs_info->subvol_srcu, srcu_index); |
| 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)) { |
| 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; |
| } |
| fs_info = BTRFS_I(inode)->root->fs_info; |
| ret = repair_io_failure(fs_info, 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); |
| |
| 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_ctx *sctx; |
| struct btrfs_trans_handle *trans = NULL; |
| struct btrfs_path *path; |
| int uncorrectable = 0; |
| |
| fixup = container_of(work, struct scrub_fixup_nodatasum, work); |
| sctx = fixup->sctx; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| spin_lock(&sctx->stat_lock); |
| ++sctx->stat.malloc_errors; |
| spin_unlock(&sctx->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(&sctx->stat_lock); |
| ++sctx->stat.corrected_errors; |
| spin_unlock(&sctx->stat_lock); |
| |
| out: |
| if (trans && !IS_ERR(trans)) |
| btrfs_end_transaction(trans, fixup->root); |
| if (uncorrectable) { |
| spin_lock(&sctx->stat_lock); |
| ++sctx->stat.uncorrectable_errors; |
| spin_unlock(&sctx->stat_lock); |
| btrfs_dev_replace_stats_inc( |
| &sctx->dev_root->fs_info->dev_replace. |
| num_uncorrectable_read_errors); |
| printk_ratelimited_in_rcu(KERN_ERR "BTRFS: " |
| "unable to fixup (nodatasum) error at logical %llu on dev %s\n", |
| fixup->logical, rcu_str_deref(fixup->dev->name)); |
| } |
| |
| btrfs_free_path(path); |
| kfree(fixup); |
| |
| scrub_pending_trans_workers_dec(sctx); |
| } |
| |
| /* |
| * scrub_handle_errored_block gets called when either verification of the |
| * pages failed or the bio failed to read, e.g. with EIO. In the latter |
| * case, this function handles all pages 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; |
| struct btrfs_fs_info *fs_info; |
| u64 length; |
| u64 logical; |
| u64 generation; |
| unsigned int failed_mirror_index; |
| unsigned int is_metadata; |
| unsigned int have_csum; |
| u8 *csum; |
| struct scrub_block *sblocks_for_recheck; /* holds one for each mirror */ |
| struct scrub_block *sblock_bad; |
| int ret; |
| int mirror_index; |
| int page_num; |
| int success; |
| static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL, |
| DEFAULT_RATELIMIT_BURST); |
| |
| BUG_ON(sblock_to_check->page_count < 1); |
| fs_info = sctx->dev_root->fs_info; |
| if (sblock_to_check->pagev[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 |
| */ |
| spin_lock(&sctx->stat_lock); |
| ++sctx->stat.super_errors; |
| spin_unlock(&sctx->stat_lock); |
| return 0; |
| } |
| length = sblock_to_check->page_count * PAGE_SIZE; |
| logical = sblock_to_check->pagev[0]->logical; |
| generation = sblock_to_check->pagev[0]->generation; |
| BUG_ON(sblock_to_check->pagev[0]->mirror_num < 1); |
| failed_mirror_index = sblock_to_check->pagev[0]->mirror_num - 1; |
| is_metadata = !(sblock_to_check->pagev[0]->flags & |
| BTRFS_EXTENT_FLAG_DATA); |
| have_csum = sblock_to_check->pagev[0]->have_csum; |
| csum = sblock_to_check->pagev[0]->csum; |
| dev = sblock_to_check->pagev[0]->dev; |
| |
| if (sctx->is_dev_replace && !is_metadata && !have_csum) { |
| sblocks_for_recheck = NULL; |
| goto nodatasum_case; |
| } |
| |
| /* |
| * 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, |
| * page by page this time in order to know which pages |
| * 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 |
| * pages from those mirrors without I/O error on the |
| * particular pages. One example (with blocks >= 2 * PAGE_SIZE) |
| * would be that mirror #1 has an I/O error on the first page, |
| * the second page is good, and mirror #2 has an I/O error on |
| * the second page, but the first page is good. |
| * Then the first page of the first mirror can be repaired by |
| * taking the first page of the second mirror, and the |
| * second page of the second mirror can be repaired by |
| * copying the contents of the 2nd page of the 1st mirror. |
| * One more note: if the pages 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 pages 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. |
| */ |
| |
| sblocks_for_recheck = kzalloc(BTRFS_MAX_MIRRORS * |
| sizeof(*sblocks_for_recheck), |
| GFP_NOFS); |
| if (!sblocks_for_recheck) { |
| 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 pages */ |
| ret = scrub_setup_recheck_block(sctx, fs_info, sblock_to_check, length, |
| logical, 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, is_metadata, have_csum, |
| csum, generation, sctx->csum_size); |
| |
| if (!sblock_bad->header_error && !sblock_bad->checksum_error && |
| sblock_bad->no_io_error_seen) { |
| /* |
| * the error disappeared after reading page by page, 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++; |
| 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; |
| } |
| |
| if (!is_metadata && !have_csum) { |
| struct scrub_fixup_nodatasum *fixup_nodatasum; |
| |
| nodatasum_case: |
| WARN_ON(sctx->is_dev_replace); |
| |
| /* |
| * !is_metadata and !have_csum, this means that the data |
| * might not be COW'ed, that it might be modified |
| * concurrently. The general strategy to work on the |
| * commit root does not help in the case when COW is not |
| * used. |
| */ |
| fixup_nodatasum = kzalloc(sizeof(*fixup_nodatasum), GFP_NOFS); |
| if (!fixup_nodatasum) |
| goto did_not_correct_error; |
| fixup_nodatasum->sctx = sctx; |
| fixup_nodatasum->dev = dev; |
| fixup_nodatasum->logical = logical; |
| fixup_nodatasum->root = fs_info->extent_root; |
| fixup_nodatasum->mirror_num = failed_mirror_index + 1; |
| scrub_pending_trans_workers_inc(sctx); |
| btrfs_init_work(&fixup_nodatasum->work, scrub_fixup_nodatasum, |
| NULL, NULL); |
| btrfs_queue_work(fs_info->scrub_workers, |
| &fixup_nodatasum->work); |
| 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 pages are rewritten that had |
| * an I/O error in the block to be repaired, since it cannot be |
| * determined, which copy of the other pages is better (and it |
| * could happen otherwise that a correct page would be |
| * overwritten by a bad one). |
| */ |
| for (mirror_index = 0; |
| mirror_index < BTRFS_MAX_MIRRORS && |
| sblocks_for_recheck[mirror_index].page_count > 0; |
| mirror_index++) { |
| struct scrub_block *sblock_other; |
| |
| if (mirror_index == failed_mirror_index) |
| continue; |
| sblock_other = sblocks_for_recheck + mirror_index; |
| |
| /* build and submit the bios, check checksums */ |
| scrub_recheck_block(fs_info, sblock_other, is_metadata, |
| have_csum, csum, generation, |
| sctx->csum_size); |
| |
| 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); |
| } else { |
| int force_write = is_metadata || have_csum; |
| |
| ret = scrub_repair_block_from_good_copy( |
| sblock_bad, sblock_other, |
| force_write); |
| } |
| if (0 == ret) |
| goto corrected_error; |
| } |
| } |
| |
| /* |
| * for dev_replace, pick good pages and write to the target device. |
| */ |
| if (sctx->is_dev_replace) { |
| success = 1; |
| for (page_num = 0; page_num < sblock_bad->page_count; |
| page_num++) { |
| int sub_success; |
| |
| sub_success = 0; |
| for (mirror_index = 0; |
| mirror_index < BTRFS_MAX_MIRRORS && |
| sblocks_for_recheck[mirror_index].page_count > 0; |
| mirror_index++) { |
| struct scrub_block *sblock_other = |
| sblocks_for_recheck + mirror_index; |
| struct scrub_page *page_other = |
| sblock_other->pagev[page_num]; |
| |
| if (!page_other->io_error) { |
| ret = scrub_write_page_to_dev_replace( |
| sblock_other, page_num); |
| if (ret == 0) { |
| /* succeeded for this page */ |
| sub_success = 1; |
| break; |
| } else { |
| btrfs_dev_replace_stats_inc( |
| &sctx->dev_root-> |
| fs_info->dev_replace. |
| num_write_errors); |
| } |
| } |
| } |
| |
| if (!sub_success) { |
| /* |
| * did not find a mirror to fetch the page |
| * from. scrub_write_page_to_dev_replace() |
| * handles this case (page->io_error), by |
| * filling the block with zeros before |
| * submitting the write request |
| */ |
| success = 0; |
| ret = scrub_write_page_to_dev_replace( |
| sblock_bad, page_num); |
| if (ret) |
| btrfs_dev_replace_stats_inc( |
| &sctx->dev_root->fs_info-> |
| dev_replace.num_write_errors); |
| } |
| } |
| |
| goto out; |
| } |
| |
| /* |
| * for regular scrub, repair those pages that are errored. |
| * In case of I/O errors in the area that is supposed to be |
| * repaired, continue by picking good copies of those pages. |
| * Select the good pages from mirrors to rewrite bad pages 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 pages from the different mirrors |
| * until the checksum verification succeeds. For example, when |
| * the 2nd page of mirror #1 faces I/O errors, and the 2nd page |
| * of mirror #2 is readable but the final checksum test fails, |
| * then the 2nd page of mirror #3 could be tried, whether now |
| * the final checksum succeedes. 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 PAGE_SIZE. 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 PAGE_SIZE |
| * area are unreadable. |
| */ |
| |
| /* can only fix I/O errors from here on */ |
| if (sblock_bad->no_io_error_seen) |
| goto did_not_correct_error; |
| |
| success = 1; |
| for (page_num = 0; page_num < sblock_bad->page_count; page_num++) { |
| struct scrub_page *page_bad = sblock_bad->pagev[page_num]; |
| |
| if (!page_bad->io_error) |
| continue; |
| |
| for (mirror_index = 0; |
| mirror_index < BTRFS_MAX_MIRRORS && |
| sblocks_for_recheck[mirror_index].page_count > 0; |
| mirror_index++) { |
| struct scrub_block *sblock_other = sblocks_for_recheck + |
| mirror_index; |
| struct scrub_page *page_other = sblock_other->pagev[ |
| page_num]; |
| |
| if (!page_other->io_error) { |
| ret = scrub_repair_page_from_good_copy( |
| sblock_bad, sblock_other, page_num, 0); |
| if (0 == ret) { |
| page_bad->io_error = 0; |
| break; /* succeeded for this page */ |
| } |
| } |
| } |
| |
| if (page_bad->io_error) { |
| /* did not find a mirror to copy the page from */ |
| success = 0; |
| } |
| } |
| |
| if (success) { |
| 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, |
| is_metadata, have_csum, csum, |
| generation, sctx->csum_size); |
| 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++; |
| spin_unlock(&sctx->stat_lock); |
| printk_ratelimited_in_rcu(KERN_ERR |
| "BTRFS: fixed up error at logical %llu on dev %s\n", |
| logical, rcu_str_deref(dev->name)); |
| } |
| } else { |
| did_not_correct_error: |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.uncorrectable_errors++; |
| spin_unlock(&sctx->stat_lock); |
| printk_ratelimited_in_rcu(KERN_ERR |
| "BTRFS: unable to fixup (regular) error at logical %llu on dev %s\n", |
| logical, rcu_str_deref(dev->name)); |
| } |
| |
| out: |
| if (sblocks_for_recheck) { |
| for (mirror_index = 0; mirror_index < BTRFS_MAX_MIRRORS; |
| mirror_index++) { |
| struct scrub_block *sblock = sblocks_for_recheck + |
| mirror_index; |
| int page_index; |
| |
| for (page_index = 0; page_index < sblock->page_count; |
| page_index++) { |
| sblock->pagev[page_index]->sblock = NULL; |
| scrub_page_put(sblock->pagev[page_index]); |
| } |
| } |
| kfree(sblocks_for_recheck); |
| } |
| |
| return 0; |
| } |
| |
| static int scrub_setup_recheck_block(struct scrub_ctx *sctx, |
| struct btrfs_fs_info *fs_info, |
| struct scrub_block *original_sblock, |
| u64 length, u64 logical, |
| struct scrub_block *sblocks_for_recheck) |
| { |
| int page_index; |
| int mirror_index; |
| int ret; |
| |
| /* |
| * note: the two members ref_count and outstanding_pages |
| * are not used (and not set) in the blocks that are used for |
| * the recheck procedure |
| */ |
| |
| page_index = 0; |
| while (length > 0) { |
| u64 sublen = min_t(u64, length, PAGE_SIZE); |
| u64 mapped_length = sublen; |
| struct btrfs_bio *bbio = NULL; |
| |
| /* |
| * with a length of PAGE_SIZE, each returned stripe |
| * represents one mirror |
| */ |
| ret = btrfs_map_block(fs_info, REQ_GET_READ_MIRRORS, logical, |
| &mapped_length, &bbio, 0); |
| if (ret || !bbio || mapped_length < sublen) { |
| kfree(bbio); |
| return -EIO; |
| } |
| |
| BUG_ON(page_index >= SCRUB_PAGES_PER_RD_BIO); |
| for (mirror_index = 0; mirror_index < (int)bbio->num_stripes; |
| mirror_index++) { |
| struct scrub_block *sblock; |
| struct scrub_page *page; |
| |
| if (mirror_index >= BTRFS_MAX_MIRRORS) |
| continue; |
| |
| sblock = sblocks_for_recheck + mirror_index; |
| sblock->sctx = sctx; |
| page = kzalloc(sizeof(*page), GFP_NOFS); |
| if (!page) { |
| leave_nomem: |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.malloc_errors++; |
| spin_unlock(&sctx->stat_lock); |
| kfree(bbio); |
| return -ENOMEM; |
| } |
| scrub_page_get(page); |
| sblock->pagev[page_index] = page; |
| page->logical = logical; |
| page->physical = bbio->stripes[mirror_index].physical; |
| BUG_ON(page_index >= original_sblock->page_count); |
| page->physical_for_dev_replace = |
| original_sblock->pagev[page_index]-> |
| physical_for_dev_replace; |
| /* for missing devices, dev->bdev is NULL */ |
| page->dev = bbio->stripes[mirror_index].dev; |
| page->mirror_num = mirror_index + 1; |
| sblock->page_count++; |
| page->page = alloc_page(GFP_NOFS); |
| if (!page->page) |
| goto leave_nomem; |
| } |
| kfree(bbio); |
| length -= sublen; |
| logical += sublen; |
| page_index++; |
| } |
| |
| return 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 pages |
| * which are errored are marked as being bad. The goal is to enable scrub |
| * to take those pages that are not errored from all the mirrors so that |
| * the pages 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 is_metadata, |
| int have_csum, u8 *csum, u64 generation, |
| u16 csum_size) |
| { |
| int page_num; |
| |
| sblock->no_io_error_seen = 1; |
| sblock->header_error = 0; |
| sblock->checksum_error = 0; |
| |
| for (page_num = 0; page_num < sblock->page_count; page_num++) { |
| struct bio *bio; |
| struct scrub_page *page = sblock->pagev[page_num]; |
| |
| if (page->dev->bdev == NULL) { |
| page->io_error = 1; |
| sblock->no_io_error_seen = 0; |
| continue; |
| } |
| |
| WARN_ON(!page->page); |
| bio = btrfs_io_bio_alloc(GFP_NOFS, 1); |
| if (!bio) { |
| page->io_error = 1; |
| sblock->no_io_error_seen = 0; |
| continue; |
| } |
| bio->bi_bdev = page->dev->bdev; |
| bio->bi_iter.bi_sector = page->physical >> 9; |
| |
| bio_add_page(bio, page->page, PAGE_SIZE, 0); |
| if (btrfsic_submit_bio_wait(READ, bio)) |
| sblock->no_io_error_seen = 0; |
| |
| bio_put(bio); |
| } |
| |
| if (sblock->no_io_error_seen) |
| scrub_recheck_block_checksum(fs_info, sblock, is_metadata, |
| have_csum, csum, generation, |
| csum_size); |
| |
| return; |
| } |
| |
| static void scrub_recheck_block_checksum(struct btrfs_fs_info *fs_info, |
| struct scrub_block *sblock, |
| int is_metadata, int have_csum, |
| const u8 *csum, u64 generation, |
| u16 csum_size) |
| { |
| int page_num; |
| u8 calculated_csum[BTRFS_CSUM_SIZE]; |
| u32 crc = ~(u32)0; |
| void *mapped_buffer; |
| |
| WARN_ON(!sblock->pagev[0]->page); |
| if (is_metadata) { |
| struct btrfs_header *h; |
| |
| mapped_buffer = kmap_atomic(sblock->pagev[0]->page); |
| h = (struct btrfs_header *)mapped_buffer; |
| |
| if (sblock->pagev[0]->logical != btrfs_stack_header_bytenr(h) || |
| memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE) || |
| memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, |
| BTRFS_UUID_SIZE)) { |
| sblock->header_error = 1; |
| } else if (generation != btrfs_stack_header_generation(h)) { |
| sblock->header_error = 1; |
| sblock->generation_error = 1; |
| } |
| csum = h->csum; |
| } else { |
| if (!have_csum) |
| return; |
| |
| mapped_buffer = kmap_atomic(sblock->pagev[0]->page); |
| } |
| |
| for (page_num = 0;;) { |
| if (page_num == 0 && is_metadata) |
| crc = btrfs_csum_data( |
| ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE, |
| crc, PAGE_SIZE - BTRFS_CSUM_SIZE); |
| else |
| crc = btrfs_csum_data(mapped_buffer, crc, PAGE_SIZE); |
| |
| kunmap_atomic(mapped_buffer); |
| page_num++; |
| if (page_num >= sblock->page_count) |
| break; |
| WARN_ON(!sblock->pagev[page_num]->page); |
| |
| mapped_buffer = kmap_atomic(sblock->pagev[page_num]->page); |
| } |
| |
| btrfs_csum_final(crc, calculated_csum); |
| if (memcmp(calculated_csum, csum, csum_size)) |
| sblock->checksum_error = 1; |
| } |
| |
| static int scrub_repair_block_from_good_copy(struct scrub_block *sblock_bad, |
| struct scrub_block *sblock_good, |
| int force_write) |
| { |
| int page_num; |
| int ret = 0; |
| |
| for (page_num = 0; page_num < sblock_bad->page_count; page_num++) { |
| int ret_sub; |
| |
| ret_sub = scrub_repair_page_from_good_copy(sblock_bad, |
| sblock_good, |
| page_num, |
| force_write); |
| if (ret_sub) |
| ret = ret_sub; |
| } |
| |
| return ret; |
| } |
| |
| static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad, |
| struct scrub_block *sblock_good, |
| int page_num, int force_write) |
| { |
| struct scrub_page *page_bad = sblock_bad->pagev[page_num]; |
| struct scrub_page *page_good = sblock_good->pagev[page_num]; |
| |
| BUG_ON(page_bad->page == NULL); |
| BUG_ON(page_good->page == NULL); |
| if (force_write || sblock_bad->header_error || |
| sblock_bad->checksum_error || page_bad->io_error) { |
| struct bio *bio; |
| int ret; |
| |
| if (!page_bad->dev->bdev) { |
| printk_ratelimited(KERN_WARNING "BTRFS: " |
| "scrub_repair_page_from_good_copy(bdev == NULL) " |
| "is unexpected!\n"); |
| return -EIO; |
| } |
| |
| bio = btrfs_io_bio_alloc(GFP_NOFS, 1); |
| if (!bio) |
| return -EIO; |
| bio->bi_bdev = page_bad->dev->bdev; |
| bio->bi_iter.bi_sector = page_bad->physical >> 9; |
| |
| ret = bio_add_page(bio, page_good->page, PAGE_SIZE, 0); |
| if (PAGE_SIZE != ret) { |
| bio_put(bio); |
| return -EIO; |
| } |
| |
| if (btrfsic_submit_bio_wait(WRITE, bio)) { |
| btrfs_dev_stat_inc_and_print(page_bad->dev, |
| BTRFS_DEV_STAT_WRITE_ERRS); |
| btrfs_dev_replace_stats_inc( |
| &sblock_bad->sctx->dev_root->fs_info-> |
| dev_replace.num_write_errors); |
| bio_put(bio); |
| return -EIO; |
| } |
| bio_put(bio); |
| } |
| |
| return 0; |
| } |
| |
| static void scrub_write_block_to_dev_replace(struct scrub_block *sblock) |
| { |
| int page_num; |
| |
| for (page_num = 0; page_num < sblock->page_count; page_num++) { |
| int ret; |
| |
| ret = scrub_write_page_to_dev_replace(sblock, page_num); |
| if (ret) |
| btrfs_dev_replace_stats_inc( |
| &sblock->sctx->dev_root->fs_info->dev_replace. |
| num_write_errors); |
| } |
| } |
| |
| static int scrub_write_page_to_dev_replace(struct scrub_block *sblock, |
| int page_num) |
| { |
| struct scrub_page *spage = sblock->pagev[page_num]; |
| |
| BUG_ON(spage->page == NULL); |
| if (spage->io_error) { |
| void *mapped_buffer = kmap_atomic(spage->page); |
| |
| memset(mapped_buffer, 0, PAGE_CACHE_SIZE); |
| flush_dcache_page(spage->page); |
| kunmap_atomic(mapped_buffer); |
| } |
| return scrub_add_page_to_wr_bio(sblock->sctx, spage); |
| } |
| |
| static int scrub_add_page_to_wr_bio(struct scrub_ctx *sctx, |
| struct scrub_page *spage) |
| { |
| struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx; |
| struct scrub_bio *sbio; |
| int ret; |
| |
| mutex_lock(&wr_ctx->wr_lock); |
| again: |
| if (!wr_ctx->wr_curr_bio) { |
| wr_ctx->wr_curr_bio = kzalloc(sizeof(*wr_ctx->wr_curr_bio), |
| GFP_NOFS); |
| if (!wr_ctx->wr_curr_bio) { |
| mutex_unlock(&wr_ctx->wr_lock); |
| return -ENOMEM; |
| } |
| wr_ctx->wr_curr_bio->sctx = sctx; |
| wr_ctx->wr_curr_bio->page_count = 0; |
| } |
| sbio = wr_ctx->wr_curr_bio; |
| if (sbio->page_count == 0) { |
| struct bio *bio; |
| |
| sbio->physical = spage->physical_for_dev_replace; |
| sbio->logical = spage->logical; |
| sbio->dev = wr_ctx->tgtdev; |
| bio = sbio->bio; |
| if (!bio) { |
| bio = btrfs_io_bio_alloc(GFP_NOFS, wr_ctx->pages_per_wr_bio); |
| if (!bio) { |
| mutex_unlock(&wr_ctx->wr_lock); |
| return -ENOMEM; |
| } |
| sbio->bio = bio; |
| } |
| |
| bio->bi_private = sbio; |
| bio->bi_end_io = scrub_wr_bio_end_io; |
| bio->bi_bdev = sbio->dev->bdev; |
| bio->bi_iter.bi_sector = sbio->physical >> 9; |
| sbio->err = 0; |
| } else if (sbio->physical + sbio->page_count * PAGE_SIZE != |
| spage->physical_for_dev_replace || |
| sbio->logical + sbio->page_count * PAGE_SIZE != |
| spage->logical) { |
| scrub_wr_submit(sctx); |
| goto again; |
| } |
| |
| ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0); |
| if (ret != PAGE_SIZE) { |
| if (sbio->page_count < 1) { |
| bio_put(sbio->bio); |
| sbio->bio = NULL; |
| mutex_unlock(&wr_ctx->wr_lock); |
| return -EIO; |
| } |
| scrub_wr_submit(sctx); |
| goto again; |
| } |
| |
| sbio->pagev[sbio->page_count] = spage; |
| scrub_page_get(spage); |
| sbio->page_count++; |
| if (sbio->page_count == wr_ctx->pages_per_wr_bio) |
| scrub_wr_submit(sctx); |
| mutex_unlock(&wr_ctx->wr_lock); |
| |
| return 0; |
| } |
| |
| static void scrub_wr_submit(struct scrub_ctx *sctx) |
| { |
| struct scrub_wr_ctx *wr_ctx = &sctx->wr_ctx; |
| struct scrub_bio *sbio; |
| |
| if (!wr_ctx->wr_curr_bio) |
| return; |
| |
| sbio = wr_ctx->wr_curr_bio; |
| wr_ctx->wr_curr_bio = NULL; |
| WARN_ON(!sbio->bio->bi_bdev); |
| 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_submit_bio(WRITE, sbio->bio); |
| } |
| |
| static void scrub_wr_bio_end_io(struct bio *bio, int err) |
| { |
| struct scrub_bio *sbio = bio->bi_private; |
| struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info; |
| |
| sbio->err = err; |
| sbio->bio = bio; |
| |
| btrfs_init_work(&sbio->work, scrub_wr_bio_end_io_worker, NULL, NULL); |
| btrfs_queue_work(fs_info->scrub_wr_completion_workers, &sbio->work); |
| } |
| |
| static void scrub_wr_bio_end_io_worker(struct btrfs_work *work) |
| { |
| struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); |
| struct scrub_ctx *sctx = sbio->sctx; |
| int i; |
| |
| WARN_ON(sbio->page_count > SCRUB_PAGES_PER_WR_BIO); |
| if (sbio->err) { |
| struct btrfs_dev_replace *dev_replace = |
| &sbio->sctx->dev_root->fs_info->dev_replace; |
| |
| for (i = 0; i < sbio->page_count; i++) { |
| struct scrub_page *spage = sbio->pagev[i]; |
| |
| spage->io_error = 1; |
| btrfs_dev_replace_stats_inc(&dev_replace-> |
| num_write_errors); |
| } |
| } |
| |
| for (i = 0; i < sbio->page_count; i++) |
| scrub_page_put(sbio->pagev[i]); |
| |
| bio_put(sbio->bio); |
| kfree(sbio); |
| scrub_pending_bio_dec(sctx); |
| } |
| |
| static int scrub_checksum(struct scrub_block *sblock) |
| { |
| u64 flags; |
| int ret; |
| |
| WARN_ON(sblock->page_count < 1); |
| flags = sblock->pagev[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) |
| (void)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; |
| u8 csum[BTRFS_CSUM_SIZE]; |
| u8 *on_disk_csum; |
| struct page *page; |
| void *buffer; |
| u32 crc = ~(u32)0; |
| int fail = 0; |
| u64 len; |
| int index; |
| |
| BUG_ON(sblock->page_count < 1); |
| if (!sblock->pagev[0]->have_csum) |
| return 0; |
| |
| on_disk_csum = sblock->pagev[0]->csum; |
| page = sblock->pagev[0]->page; |
| buffer = kmap_atomic(page); |
| |
| len = sctx->sectorsize; |
| index = 0; |
| for (;;) { |
| u64 l = min_t(u64, len, PAGE_SIZE); |
| |
| crc = btrfs_csum_data(buffer, crc, l); |
| kunmap_atomic(buffer); |
| len -= l; |
| if (len == 0) |
| break; |
| index++; |
| BUG_ON(index >= sblock->page_count); |
| BUG_ON(!sblock->pagev[index]->page); |
| page = sblock->pagev[index]->page; |
| buffer = kmap_atomic(page); |
| } |
| |
| btrfs_csum_final(crc, csum); |
| if (memcmp(csum, on_disk_csum, sctx->csum_size)) |
| fail = 1; |
| |
| return fail; |
| } |
| |
| static int scrub_checksum_tree_block(struct scrub_block *sblock) |
| { |
| struct scrub_ctx *sctx = sblock->sctx; |
| struct btrfs_header *h; |
| struct btrfs_root *root = sctx->dev_root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| u8 calculated_csum[BTRFS_CSUM_SIZE]; |
| u8 on_disk_csum[BTRFS_CSUM_SIZE]; |
| struct page *page; |
| void *mapped_buffer; |
| u64 mapped_size; |
| void *p; |
| u32 crc = ~(u32)0; |
| int fail = 0; |
| int crc_fail = 0; |
| u64 len; |
| int index; |
| |
| BUG_ON(sblock->page_count < 1); |
| page = sblock->pagev[0]->page; |
| mapped_buffer = kmap_atomic(page); |
| h = (struct btrfs_header *)mapped_buffer; |
| memcpy(on_disk_csum, h->csum, sctx->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->pagev[0]->logical != btrfs_stack_header_bytenr(h)) |
| ++fail; |
| |
| if (sblock->pagev[0]->generation != btrfs_stack_header_generation(h)) |
| ++fail; |
| |
| if (memcmp(h->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) |
| ++fail; |
| |
| if (memcmp(h->chunk_tree_uuid, fs_info->chunk_tree_uuid, |
| BTRFS_UUID_SIZE)) |
| ++fail; |
| |
| WARN_ON(sctx->nodesize != sctx->leafsize); |
| len = sctx->nodesize - BTRFS_CSUM_SIZE; |
| mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE; |
| p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE; |
| index = 0; |
| for (;;) { |
| u64 l = min_t(u64, len, mapped_size); |
| |
| crc = btrfs_csum_data(p, crc, l); |
| kunmap_atomic(mapped_buffer); |
| len -= l; |
| if (len == 0) |
| break; |
| index++; |
| BUG_ON(index >= sblock->page_count); |
| BUG_ON(!sblock->pagev[index]->page); |
| page = sblock->pagev[index]->page; |
| mapped_buffer = kmap_atomic(page); |
| mapped_size = PAGE_SIZE; |
| p = mapped_buffer; |
| } |
| |
| btrfs_csum_final(crc, calculated_csum); |
| if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size)) |
| ++crc_fail; |
| |
| return fail || crc_fail; |
| } |
| |
| static int scrub_checksum_super(struct scrub_block *sblock) |
| { |
| struct btrfs_super_block *s; |
| struct scrub_ctx *sctx = sblock->sctx; |
| struct btrfs_root *root = sctx->dev_root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| u8 calculated_csum[BTRFS_CSUM_SIZE]; |
| u8 on_disk_csum[BTRFS_CSUM_SIZE]; |
| struct page *page; |
| void *mapped_buffer; |
| u64 mapped_size; |
| void *p; |
| u32 crc = ~(u32)0; |
| int fail_gen = 0; |
| int fail_cor = 0; |
| u64 len; |
| int index; |
| |
| BUG_ON(sblock->page_count < 1); |
| page = sblock->pagev[0]->page; |
| mapped_buffer = kmap_atomic(page); |
| s = (struct btrfs_super_block *)mapped_buffer; |
| memcpy(on_disk_csum, s->csum, sctx->csum_size); |
| |
| if (sblock->pagev[0]->logical != btrfs_super_bytenr(s)) |
| ++fail_cor; |
| |
| if (sblock->pagev[0]->generation != btrfs_super_generation(s)) |
| ++fail_gen; |
| |
| if (memcmp(s->fsid, fs_info->fsid, BTRFS_UUID_SIZE)) |
| ++fail_cor; |
| |
| len = BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE; |
| mapped_size = PAGE_SIZE - BTRFS_CSUM_SIZE; |
| p = ((u8 *)mapped_buffer) + BTRFS_CSUM_SIZE; |
| index = 0; |
| for (;;) { |
| u64 l = min_t(u64, len, mapped_size); |
| |
| crc = btrfs_csum_data(p, crc, l); |
| kunmap_atomic(mapped_buffer); |
| len -= l; |
| if (len == 0) |
| break; |
| index++; |
| BUG_ON(index >= sblock->page_count); |
| BUG_ON(!sblock->pagev[index]->page); |
| page = sblock->pagev[index]->page; |
| mapped_buffer = kmap_atomic(page); |
| mapped_size = PAGE_SIZE; |
| p = mapped_buffer; |
| } |
| |
| btrfs_csum_final(crc, calculated_csum); |
| if (memcmp(calculated_csum, on_disk_csum, sctx->csum_size)) |
| ++fail_cor; |
| |
| if (fail_cor + fail_gen) { |
| /* |
| * if we find an error in a super block, we just report it. |
| * They will get written with the next transaction commit |
| * anyway |
| */ |
| spin_lock(&sctx->stat_lock); |
| ++sctx->stat.super_errors; |
| spin_unlock(&sctx->stat_lock); |
| if (fail_cor) |
| btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev, |
| BTRFS_DEV_STAT_CORRUPTION_ERRS); |
| else |
| btrfs_dev_stat_inc_and_print(sblock->pagev[0]->dev, |
| BTRFS_DEV_STAT_GENERATION_ERRS); |
| } |
| |
| return fail_cor + fail_gen; |
| } |
| |
| static void scrub_block_get(struct scrub_block *sblock) |
| { |
| atomic_inc(&sblock->ref_count); |
| } |
| |
| static void scrub_block_put(struct scrub_block *sblock) |
| { |
| if (atomic_dec_and_test(&sblock->ref_count)) { |
| int i; |
| |
| for (i = 0; i < sblock->page_count; i++) |
| scrub_page_put(sblock->pagev[i]); |
| kfree(sblock); |
| } |
| } |
| |
| static void scrub_page_get(struct scrub_page *spage) |
| { |
| atomic_inc(&spage->ref_count); |
| } |
| |
| static void scrub_page_put(struct scrub_page *spage) |
| { |
| if (atomic_dec_and_test(&spage->ref_count)) { |
| if (spage->page) |
| __free_page(spage->page); |
| kfree(spage); |
| } |
| } |
| |
| static void scrub_submit(struct scrub_ctx *sctx) |
| { |
| struct scrub_bio *sbio; |
| |
| if (sctx->curr == -1) |
| return; |
| |
| sbio = sctx->bios[sctx->curr]; |
| sctx->curr = -1; |
| scrub_pending_bio_inc(sctx); |
| |
| if (!sbio->bio->bi_bdev) { |
| /* |
| * this case should not happen. If btrfs_map_block() is |
| * wrong, it could happen for dev-replace operations on |
| * missing devices when no mirrors are available, but in |
| * this case it should already fail the mount. |
| * This case is handled correctly (but _very_ slowly). |
| */ |
| printk_ratelimited(KERN_WARNING |
| "BTRFS: scrub_submit(bio bdev == NULL) is unexpected!\n"); |
| bio_endio(sbio->bio, -EIO); |
| } else { |
| btrfsic_submit_bio(READ, sbio->bio); |
| } |
| } |
| |
| static int scrub_add_page_to_rd_bio(struct scrub_ctx *sctx, |
| struct scrub_page *spage) |
| { |
| struct scrub_block *sblock = spage->sblock; |
| struct scrub_bio *sbio; |
| 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]->page_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->page_count == 0) { |
| struct bio *bio; |
| |
| sbio->physical = spage->physical; |
| sbio->logical = spage->logical; |
| sbio->dev = spage->dev; |
| bio = sbio->bio; |
| if (!bio) { |
| bio = btrfs_io_bio_alloc(GFP_NOFS, sctx->pages_per_rd_bio); |
| if (!bio) |
| return -ENOMEM; |
| sbio->bio = bio; |
| } |
| |
| bio->bi_private = sbio; |
| bio->bi_end_io = scrub_bio_end_io; |
| bio->bi_bdev = sbio->dev->bdev; |
| bio->bi_iter.bi_sector = sbio->physical >> 9; |
| sbio->err = 0; |
| } else if (sbio->physical + sbio->page_count * PAGE_SIZE != |
| spage->physical || |
| sbio->logical + sbio->page_count * PAGE_SIZE != |
| spage->logical || |
| sbio->dev != spage->dev) { |
| scrub_submit(sctx); |
| goto again; |
| } |
| |
| sbio->pagev[sbio->page_count] = spage; |
| ret = bio_add_page(sbio->bio, spage->page, PAGE_SIZE, 0); |
| if (ret != PAGE_SIZE) { |
| if (sbio->page_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_pages); |
| sbio->page_count++; |
| if (sbio->page_count == sctx->pages_per_rd_bio) |
| scrub_submit(sctx); |
| |
| return 0; |
| } |
| |
| static int scrub_pages(struct scrub_ctx *sctx, u64 logical, u64 len, |
| u64 physical, struct btrfs_device *dev, u64 flags, |
| u64 gen, int mirror_num, u8 *csum, int force, |
| u64 physical_for_dev_replace) |
| { |
| struct scrub_block *sblock; |
| int index; |
| |
| sblock = kzalloc(sizeof(*sblock), GFP_NOFS); |
| if (!sblock) { |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.malloc_errors++; |
| spin_unlock(&sctx->stat_lock); |
| return -ENOMEM; |
| } |
| |
| /* one ref inside this function, plus one for each page added to |
| * a bio later on */ |
| atomic_set(&sblock->ref_count, 1); |
| sblock->sctx = sctx; |
| sblock->no_io_error_seen = 1; |
| |
| for (index = 0; len > 0; index++) { |
| struct scrub_page *spage; |
| u64 l = min_t(u64, len, PAGE_SIZE); |
| |
| spage = kzalloc(sizeof(*spage), GFP_NOFS); |
| if (!spage) { |
| leave_nomem: |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.malloc_errors++; |
| spin_unlock(&sctx->stat_lock); |
| scrub_block_put(sblock); |
| return -ENOMEM; |
| } |
| BUG_ON(index >= SCRUB_MAX_PAGES_PER_BLOCK); |
| scrub_page_get(spage); |
| sblock->pagev[index] = spage; |
| spage->sblock = sblock; |
| spage->dev = dev; |
| spage->flags = flags; |
| spage->generation = gen; |
| spage->logical = logical; |
| spage->physical = physical; |
| spage->physical_for_dev_replace = physical_for_dev_replace; |
| spage->mirror_num = mirror_num; |
| if (csum) { |
| spage->have_csum = 1; |
| memcpy(spage->csum, csum, sctx->csum_size); |
| } else { |
| spage->have_csum = 0; |
| } |
| sblock->page_count++; |
| spage->page = alloc_page(GFP_NOFS); |
| if (!spage->page) |
| goto leave_nomem; |
| len -= l; |
| logical += l; |
| physical += l; |
| physical_for_dev_replace += l; |
| } |
| |
| WARN_ON(sblock->page_count == 0); |
| for (index = 0; index < sblock->page_count; index++) { |
| struct scrub_page *spage = sblock->pagev[index]; |
| int ret; |
| |
| ret = scrub_add_page_to_rd_bio(sctx, spage); |
| if (ret) { |
| scrub_block_put(sblock); |
| return ret; |
| } |
| } |
| |
| if (force) |
| scrub_submit(sctx); |
| |
| /* last one frees, either here or in bio completion for last page */ |
| scrub_block_put(sblock); |
| return 0; |
| } |
| |
| static void scrub_bio_end_io(struct bio *bio, int err) |
| { |
| struct scrub_bio *sbio = bio->bi_private; |
| struct btrfs_fs_info *fs_info = sbio->dev->dev_root->fs_info; |
| |
| sbio->err = err; |
| sbio->bio = bio; |
| |
| btrfs_queue_work(fs_info->scrub_workers, &sbio->work); |
| } |
| |
| static void scrub_bio_end_io_worker(struct btrfs_work *work) |
| { |
| struct scrub_bio *sbio = container_of(work, struct scrub_bio, work); |
| struct scrub_ctx *sctx = sbio->sctx; |
| int i; |
| |
| BUG_ON(sbio->page_count > SCRUB_PAGES_PER_RD_BIO); |
| if (sbio->err) { |
| for (i = 0; i < sbio->page_count; i++) { |
| struct scrub_page *spage = sbio->pagev[i]; |
| |
| spage->io_error = 1; |
| spage->sblock->no_io_error_seen = 0; |
| } |
| } |
| |
| /* now complete the scrub_block items that have all pages completed */ |
| for (i = 0; i < sbio->page_count; i++) { |
| struct scrub_page *spage = sbio->pagev[i]; |
| struct scrub_block *sblock = spage->sblock; |
| |
| if (atomic_dec_and_test(&sblock->outstanding_pages)) |
| 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 && |
| atomic_read(&sctx->wr_ctx.flush_all_writes)) { |
| mutex_lock(&sctx->wr_ctx.wr_lock); |
| scrub_wr_submit(sctx); |
| mutex_unlock(&sctx->wr_ctx.wr_lock); |
| } |
| |
| scrub_pending_bio_dec(sctx); |
| } |
| |
| static void scrub_block_complete(struct scrub_block *sblock) |
| { |
| if (!sblock->no_io_error_seen) { |
| 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. |
| */ |
| if (!scrub_checksum(sblock) && sblock->sctx->is_dev_replace) |
| scrub_write_block_to_dev_replace(sblock); |
| } |
| } |
| |
| static int scrub_find_csum(struct scrub_ctx *sctx, u64 logical, u64 len, |
| u8 *csum) |
| { |
| struct btrfs_ordered_sum *sum = NULL; |
| unsigned long index; |
| unsigned long num_sectors; |
| |
| while (!list_empty(&sctx->csum_list)) { |
| sum = list_first_entry(&sctx->csum_list, |
| struct btrfs_ordered_sum, list); |
| if (sum->bytenr > logical) |
| return 0; |
| if (sum->bytenr + sum->len > logical) |
| break; |
| |
| ++sctx->stat.csum_discards; |
| list_del(&sum->list); |
| kfree(sum); |
| sum = NULL; |
| } |
| if (!sum) |
| return 0; |
| |
| index = ((u32)(logical - sum->bytenr)) / sctx->sectorsize; |
| num_sectors = sum->len / sctx->sectorsize; |
| memcpy(csum, sum->sums + index, sctx->csum_size); |
| if (index == num_sectors - 1) { |
| list_del(&sum->list); |
| kfree(sum); |
| } |
| return 1; |
| } |
| |
| /* scrub extent tries to collect up to 64 kB for each bio */ |
| static int scrub_extent(struct scrub_ctx *sctx, u64 logical, u64 len, |
| u64 physical, struct btrfs_device *dev, u64 flags, |
| u64 gen, int mirror_num, u64 physical_for_dev_replace) |
| { |
| int ret; |
| u8 csum[BTRFS_CSUM_SIZE]; |
| u32 blocksize; |
| |
| if (flags & BTRFS_EXTENT_FLAG_DATA) { |
| blocksize = sctx->sectorsize; |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.data_extents_scrubbed++; |
| sctx->stat.data_bytes_scrubbed += len; |
| spin_unlock(&sctx->stat_lock); |
| } else if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { |
| WARN_ON(sctx->nodesize != sctx->leafsize); |
| blocksize = sctx->nodesize; |
| spin_lock(&sctx->stat_lock); |
| sctx->stat.tree_extents_scrubbed++; |
| sctx->stat.tree_bytes_scrubbed += len; |
| spin_unlock(&sctx->stat_lock); |
| } else { |
| blocksize = sctx->sectorsize; |
| WARN_ON(1); |
| } |
| |
| while (len) { |
| u64 l = min_t(u64, len, blocksize); |
| int have_csum = 0; |
| |
| if (flags & BTRFS_EXTENT_FLAG_DATA) { |
| /* push csums to sbio */ |
| have_csum = scrub_find_csum(sctx, logical, l, csum); |
| if (have_csum == 0) |
| ++sctx->stat.no_csum; |
| if (sctx->is_dev_replace && !have_csum) { |
| ret = copy_nocow_pages(sctx, logical, l, |
| mirror_num, |
| physical_for_dev_replace); |
| goto behind_scrub_pages; |
| } |
| } |
| ret = scrub_pages(sctx, logical, l, physical, dev, flags, gen, |
| mirror_num, have_csum ? csum : NULL, 0, |
| physical_for_dev_replace); |
| behind_scrub_pages: |
| if (ret) |
| return ret; |
| len -= l; |
| logical += l; |
| physical += l; |
| physical_for_dev_replace += 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) |
| { |
| int i; |
| int j = 0; |
| u64 stripe_nr; |
| u64 last_offset; |
| int stripe_index; |
| int rot; |
| |
| last_offset = (physical - map->stripes[num].physical) * |
| nr_data_stripes(map); |
| *offset = last_offset; |
| for (i = 0; i < nr_data_stripes(map); i++) { |
| *offset = last_offset + i * map->stripe_len; |
| |
| stripe_nr = *offset; |
| do_div(stripe_nr, map->stripe_len); |
| do_div(stripe_nr, nr_data_stripes(map)); |
| |
| /* Work out the disk rotation on this stripe-set */ |
| rot = do_div(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 * map->stripe_len; |
| return 1; |
| } |
| |
| static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, |
| struct map_lookup *map, |
| struct btrfs_device *scrub_dev, |
| int num, u64 base, u64 length, |
| int is_dev_replace) |
| { |
| struct btrfs_path *path; |
| struct btrfs_fs_info *fs_info = sctx->dev_root->fs_info; |
| struct btrfs_root *root = fs_info->extent_root; |
| struct btrfs_root *csum_root = fs_info->csum_root; |
| struct btrfs_extent_item *extent; |
| struct blk_plug plug; |
| u64 flags; |
| int ret; |
| int slot; |
| u64 nstripes; |
| struct extent_buffer *l; |
| struct btrfs_key key; |
| u64 physical; |
| u64 logical; |
| u64 logic_end; |
| u64 physical_end; |
| u64 generation; |
| 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; |
| u64 extent_logical; |
| u64 extent_physical; |
| u64 extent_len; |
| struct btrfs_device *extent_dev; |
| int extent_mirror_num; |
| int stop_loop = 0; |
| |
| nstripes = length; |
| physical = map->stripes[num].physical; |
| offset = 0; |
| do_div(nstripes, map->stripe_len); |
| if (map->type & BTRFS_BLOCK_GROUP_RAID0) { |
| offset = map->stripe_len * num; |
| increment = map->stripe_len * map->num_stripes; |
| 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 + 1; |
| } else if (map->type & BTRFS_BLOCK_GROUP_RAID1) { |
| increment = map->stripe_len; |
| 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 + 1; |
| } else if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | |
| BTRFS_BLOCK_GROUP_RAID6)) { |
| get_raid56_logic_offset(physical, num, map, &offset); |
| increment = map->stripe_len * nr_data_stripes(map); |
| mirror_num = 1; |
| } else { |
| increment = map->stripe_len; |
| mirror_num = 1; |
| } |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| /* |
| * work on commit root. The related disk blocks are static as |
| * long as COW is applied. This means, it is save to rewrite |
| * them to repair disk errors without any race conditions |
| */ |
| path->search_commit_root = 1; |
| path->skip_locking = 1; |
| |
| /* |
| * 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_end = physical + nstripes * map->stripe_len; |
| if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | |
| BTRFS_BLOCK_GROUP_RAID6)) { |
| get_raid56_logic_offset(physical_end, num, |
| map, &logic_end); |
| logic_end += base; |
| } else { |
| logic_end = logical + increment * nstripes; |
| } |
| wait_event(sctx->list_wait, |
| atomic_read(&sctx->bios_in_flight) == 0); |
| scrub_blocked_if_needed(fs_info); |
| |
| /* 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 = logic_end; |
| key_end.type = BTRFS_METADATA_ITEM_KEY; |
| key_end.offset = (u64)-1; |
| 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 = logic_end; |
| 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); |
| |
| |
| /* |
| * collect all data csums for the stripe to avoid seeking during |
| * the scrub. This might currently (crc32) end up to be about 1MB |
| */ |
| blk_start_plug(&plug); |
| |
| /* |
| * now find all extents for each stripe and scrub them |
| */ |
| ret = 0; |
| while (physical < physical_end) { |
| /* for raid56, we skip parity stripe */ |
| if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | |
| BTRFS_BLOCK_GROUP_RAID6)) { |
| ret = get_raid56_logic_offset(physical, num, |
| map, &logical); |
| logical += base; |
| if (ret) |
| goto skip; |
| } |
| /* |
| * canceled? |
| */ |
| if (atomic_read(&fs_info->scrub_cancel_req) || |
| atomic_read(&sctx->cancel_req)) { |
| ret = -ECANCELED; |
| goto out; |
| } |
| /* |
| * check to see if we have to pause |
| */ |
| if (atomic_read(&fs_info->scrub_pause_req)) { |
| /* push queued extents */ |
| atomic_set(&sctx->wr_ctx.flush_all_writes, 1); |
| scrub_submit(sctx); |
| mutex_lock(&sctx->wr_ctx.wr_lock); |
| scrub_wr_submit(sctx); |
| mutex_unlock(&sctx->wr_ctx.wr_lock); |
| wait_event(sctx->list_wait, |
| atomic_read(&sctx->bios_in_flight) == 0); |
| atomic_set(&sctx->wr_ctx.flush_all_writes, 0); |
| scrub_blocked_if_needed(fs_info); |
| } |
| |
| if (btrfs_fs_incompat(fs_info, SKINNY_METADATA)) |
| key.type = BTRFS_METADATA_ITEM_KEY; |
| else |
| key.type = BTRFS_EXTENT_ITEM_KEY; |
| key.objectid = logical; |
| key.offset = (u64)-1; |
| |
| ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); |
| if (ret < 0) |
| goto out; |
| |
| if (ret > 0) { |
| ret = btrfs_previous_extent_item(root, path, 0); |
| if (ret < 0) |
| goto out; |
| if (ret > 0) { |
| /* there's no smaller item, so stick with the |
| * larger one */ |
| btrfs_release_path(path); |
| ret = btrfs_search_slot(NULL, root, &key, |
| path, 0, 0); |
| if (ret < 0) |
| goto out; |
| } |
| } |
| |
| stop_loop = 0; |
| while (1) { |
| u64 bytes; |
| |
| 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; |
| |
| stop_loop = 1; |
| break; |
| } |
| btrfs_item_key_to_cpu(l, &key, slot); |
| |
| if (key.type == BTRFS_METADATA_ITEM_KEY) |
| bytes = root->leafsize; |
| else |
| bytes = key.offset; |
| |
| if (key.objectid + bytes <= logical) |
| goto next; |
| |
| if (key.type != BTRFS_EXTENT_ITEM_KEY && |
| key.type != BTRFS_METADATA_ITEM_KEY) |
| goto next; |
| |
| if (key.objectid >= logical + map->stripe_len) { |
| /* out of this device extent */ |
| if (key.objectid >= logic_end) |
| stop_loop = 1; |
| break; |
| } |
| |
| extent = btrfs_item_ptr(l, slot, |
| struct btrfs_extent_item); |
| flags = btrfs_extent_flags(l, extent); |
| generation = btrfs_extent_generation(l, extent); |
| |
| if (key.objectid < logical && |
| (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) { |
| btrfs_err(fs_info, |
| "scrub: tree block %llu spanning " |
| "stripes, ignored. logical=%llu", |
| key.objectid, logical); |
| goto next; |
| } |
| |
| again: |
| extent_logical = key.objectid; |
| extent_len = bytes; |
| |
| /* |
| * trim extent to this stripe |
| */ |
| if (extent_logical < logical) { |
| extent_len -= logical - extent_logical; |
| extent_logical = logical; |
| } |
| if (extent_logical + extent_len > |
| logical + map->stripe_len) { |
| extent_len = logical + map->stripe_len - |
| extent_logical; |
| } |
| |
| extent_physical = extent_logical - logical + physical; |
| extent_dev = scrub_dev; |
| extent_mirror_num = mirror_num; |
| if (is_dev_replace) |
| scrub_remap_extent(fs_info, extent_logical, |
| extent_len, &extent_physical, |
| &extent_dev, |
| &extent_mirror_num); |
| |
| ret = btrfs_lookup_csums_range(csum_root, logical, |
| logical + map->stripe_len - 1, |
| &sctx->csum_list, 1); |
| if (ret) |
| goto out; |
| |
| ret = scrub_extent(sctx, extent_logical, extent_len, |
| extent_physical, extent_dev, flags, |
| generation, extent_mirror_num, |
| extent_logical - logical + physical); |
| if (ret) |
| goto out; |
| |
| scrub_free_csums(sctx); |
| if (extent_logical + extent_len < |
| key.objectid + bytes) { |
| if (map->type & (BTRFS_BLOCK_GROUP_RAID5 | |
| BTRFS_BLOCK_GROUP_RAID6)) { |
| /* |
| * loop until we find next data stripe |
| * or we have finished all stripes. |
| */ |
| do { |
| physical += map->stripe_len; |
| ret = get_raid56_logic_offset( |
| physical, num, |
| map, &logical); |
| logical += base; |
| } while (physical < physical_end && ret); |
| } else { |
| physical += map->stripe_len; |
| logical += increment; |
| } |
| if (logical < key.objectid + bytes) { |
| cond_resched(); |
| goto again; |
| } |
| |
| if (physical >= physical_end) { |
| stop_loop = 1; |
| break; |
| } |
| } |
| next: |
| path->slots[0]++; |
| } |
| btrfs_release_path(path); |
| skip: |
| logical += increment; |
| physical += map->stripe_len; |
| spin_lock(&sctx->stat_lock); |
| if (stop_loop) |
| sctx->stat.last_physical = map->stripes[num].physical + |
| length; |
| 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_ctx.wr_lock); |
| scrub_wr_submit(sctx); |
| mutex_unlock(&sctx->wr_ctx.wr_lock); |
| |
| blk_finish_plug(&plug); |
| btrfs_free_path(path); |
| return ret < 0 ? ret : 0; |
| } |
| |
| static noinline_for_stack int scrub_chunk(struct scrub_ctx *sctx, |
| struct btrfs_device *scrub_dev, |
| u64 chunk_tree, u64 chunk_objectid, |
| u64 chunk_offset, u64 length, |
| u64 dev_offset, int is_dev_replace) |
| { |
| struct btrfs_mapping_tree *map_tree = |
| &sctx->dev_root->fs_info->mapping_tree; |
| struct map_lookup *map; |
| struct extent_map *em; |
| int i; |
| int ret = 0; |
| |
| read_lock(&map_tree->map_tree.lock); |
| em = lookup_extent_mapping(&map_tree->map_tree, chunk_offset, 1); |
| read_unlock(&map_tree->map_tree.lock); |
| |
| if (!em) |
| return -EINVAL; |
| |
| map = (struct map_lookup *)em->bdev; |
| if (em->start != chunk_offset) |
| goto out; |
| |
| if (em->len < length) |
| goto out; |
| |
| 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, map, scrub_dev, i, |
| chunk_offset, length, |
| is_dev_replace); |
| if (ret) |
| goto out; |
| } |
| } |
| out: |
| free_extent_map(em); |
| |
| return ret; |
| } |
| |
| static noinline_for_stack |
| int scrub_enumerate_chunks(struct scrub_ctx *sctx, |
| struct btrfs_device *scrub_dev, u64 start, u64 end, |
| int is_dev_replace) |
| { |
| struct btrfs_dev_extent *dev_extent = NULL; |
| struct btrfs_path *path; |
| struct btrfs_root *root = sctx->dev_root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| u64 length; |
| u64 chunk_tree; |
| u64 chunk_objectid; |
| u64 chunk_offset; |
| int ret; |
| int slot; |
| struct extent_buffer *l; |
| struct btrfs_key key; |
| struct btrfs_key found_key; |
| struct btrfs_block_group_cache *cache; |
| struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| path->reada = 2; |
| 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) { |
| 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) |
| break; |
| } |
| } |
| |
| 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 (btrfs_key_type(&found_key) != 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); |
| length = btrfs_dev_extent_length(l, dev_extent); |
| |
| if (found_key.offset + length <= start) |
| goto skip; |
| |
| chunk_tree = btrfs_dev_extent_chunk_tree(l, dev_extent); |
| chunk_objectid = btrfs_dev_extent_chunk_objectid(l, dev_extent); |
| 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; |
| |
| dev_replace->cursor_right = found_key.offset + length; |
| dev_replace->cursor_left = found_key.offset; |
| dev_replace->item_needs_writeback = 1; |
| ret = scrub_chunk(sctx, scrub_dev, chunk_tree, chunk_objectid, |
| chunk_offset, length, found_key.offset, |
| is_dev_replace); |
| |
| /* |
| * 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. |
| */ |
| atomic_set(&sctx->wr_ctx.flush_all_writes, 1); |
| scrub_submit(sctx); |
| mutex_lock(&sctx->wr_ctx.wr_lock); |
| scrub_wr_submit(sctx); |
| mutex_unlock(&sctx->wr_ctx.wr_lock); |
| |
| wait_event(sctx->list_wait, |
| atomic_read(&sctx->bios_in_flight) == 0); |
| atomic_inc(&fs_info->scrubs_paused); |
| wake_up(&fs_info->scrub_pause_wait); |
| |
| /* |
| * 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); |
| atomic_set(&sctx->wr_ctx.flush_all_writes, 0); |
| |
| 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); |
| |
| btrfs_put_block_group(cache); |
| if (ret) |
| break; |
| if (is_dev_replace && |
| atomic64_read(&dev_replace->num_write_errors) > 0) { |
| ret = -EIO; |
| break; |
| } |
| if (sctx->stat.malloc_errors > 0) { |
| ret = -ENOMEM; |
| break; |
| } |
| |
| dev_replace->cursor_left = dev_replace->cursor_right; |
| dev_replace->item_needs_writeback = 1; |
| skip: |
| key.offset = found_key.offset + length; |
| btrfs_release_path(path); |
| } |
| |
| btrfs_free_path(path); |
| |
| /* |
| * ret can still be 1 from search_slot or next_leaf, |
| * that's not an error |
| */ |
| return ret < 0 ? ret : 0; |
| } |
| |
| static noinline_for_stack int scrub_supers(struct scrub_ctx *sctx, |
| struct btrfs_device *scrub_dev) |
| { |
| int i; |
| u64 bytenr; |
| u64 gen; |
| int ret; |
| struct btrfs_root *root = sctx->dev_root; |
| |
| if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) |
| return -EIO; |
| |
| gen = root->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->total_bytes) |
| break; |
| |
| ret = scrub_pages(sctx, bytenr, BTRFS_SUPER_INFO_SIZE, bytenr, |
| scrub_dev, BTRFS_EXTENT_FLAG_SUPER, gen, i, |
| NULL, 1, bytenr); |
| if (ret) |
| return ret; |
| } |
| wait_event(sctx->list_wait, atomic_read(&sctx->bios_in_flight) == 0); |
| |
| return 0; |
| } |
| |
| /* |
| * 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) |
| { |
| int ret = 0; |
| int flags = WQ_FREEZABLE | WQ_UNBOUND; |
| int max_active = fs_info->thread_pool_size; |
| |
| if (fs_info->scrub_workers_refcnt == 0) { |
| if (is_dev_replace) |
| fs_info->scrub_workers = |
| btrfs_alloc_workqueue("btrfs-scrub", flags, |
| 1, 4); |
| else |
| fs_info->scrub_workers = |
| btrfs_alloc_workqueue("btrfs-scrub", flags, |
| max_active, 4); |
| if (!fs_info->scrub_workers) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| fs_info->scrub_wr_completion_workers = |
| btrfs_alloc_workqueue("btrfs-scrubwrc", flags, |
| max_active, 2); |
| if (!fs_info->scrub_wr_completion_workers) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| fs_info->scrub_nocow_workers = |
| btrfs_alloc_workqueue("btrfs-scrubnc", flags, 1, 0); |
| if (!fs_info->scrub_nocow_workers) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| } |
| ++fs_info->scrub_workers_refcnt; |
| out: |
| return ret; |
| } |
| |
| static noinline_for_stack void scrub_workers_put(struct btrfs_fs_info *fs_info) |
| { |
| if (--fs_info->scrub_workers_refcnt == 0) { |
| btrfs_destroy_workqueue(fs_info->scrub_workers); |
| btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers); |
| btrfs_destroy_workqueue(fs_info->scrub_nocow_workers); |
| } |
| WARN_ON(fs_info->scrub_workers_refcnt < 0); |
| } |
| |
| 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 scrub_ctx *sctx; |
| int ret; |
| struct btrfs_device *dev; |
| |
| if (btrfs_fs_closing(fs_info)) |
| return -EINVAL; |
| |
| /* |
| * check some assumptions |
| */ |
| if (fs_info->chunk_root->nodesize != fs_info->chunk_root->leafsize) { |
| btrfs_err(fs_info, |
| "scrub: size assumption nodesize == leafsize (%d == %d) fails", |
| fs_info->chunk_root->nodesize, |
| fs_info->chunk_root->leafsize); |
| return -EINVAL; |
| } |
| |
| if (fs_info->chunk_root->nodesize > BTRFS_STRIPE_LEN) { |
| /* |
| * in this case scrub is unable to calculate the checksum |
| * the way scrub is implemented. Do not handle this |
| * situation at all because it won't ever happen. |
| */ |
| btrfs_err(fs_info, |
| "scrub: size assumption nodesize <= BTRFS_STRIPE_LEN (%d <= %d) fails", |
| fs_info->chunk_root->nodesize, BTRFS_STRIPE_LEN); |
| return -EINVAL; |
| } |
| |
| if (fs_info->chunk_root->sectorsize != PAGE_SIZE) { |
| /* not supported for data w/o checksums */ |
| btrfs_err(fs_info, |
| "scrub: size assumption sectorsize != PAGE_SIZE " |
| "(%d != %lu) fails", |
| fs_info->chunk_root->sectorsize, PAGE_SIZE); |
| return -EINVAL; |
| } |
| |
| if (fs_info->chunk_root->nodesize > |
| PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK || |
| fs_info->chunk_root->sectorsize > |
| PAGE_SIZE * SCRUB_MAX_PAGES_PER_BLOCK) { |
| /* |
| * would exhaust the array bounds of pagev member in |
| * struct scrub_block |
| */ |
| btrfs_err(fs_info, "scrub: size assumption nodesize and sectorsize " |
| "<= SCRUB_MAX_PAGES_PER_BLOCK (%d <= %d && %d <= %d) fails", |
| fs_info->chunk_root->nodesize, |
| SCRUB_MAX_PAGES_PER_BLOCK, |
| fs_info->chunk_root->sectorsize, |
| SCRUB_MAX_PAGES_PER_BLOCK); |
| return -EINVAL; |
| } |
| |
| |
| mutex_lock(&fs_info->fs_devices->device_list_mutex); |
| dev = btrfs_find_device(fs_info, devid, NULL, NULL); |
| if (!dev || (dev->missing && !is_dev_replace)) { |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| return -ENODEV; |
| } |
| |
| mutex_lock(&fs_info->scrub_lock); |
| if (!dev->in_fs_metadata || dev->is_tgtdev_for_dev_replace) { |
| mutex_unlock(&fs_info->scrub_lock); |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| return -EIO; |
| } |
| |
| btrfs_dev_replace_lock(&fs_info->dev_replace); |
| if (dev->scrub_device || |
| (!is_dev_replace && |
| btrfs_dev_replace_is_ongoing(&fs_info->dev_replace))) { |
| btrfs_dev_replace_unlock(&fs_info->dev_replace); |
| mutex_unlock(&fs_info->scrub_lock); |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| return -EINPROGRESS; |
| } |
| btrfs_dev_replace_unlock(&fs_info->dev_replace); |
| |
| ret = scrub_workers_get(fs_info, is_dev_replace); |
| if (ret) { |
| mutex_unlock(&fs_info->scrub_lock); |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| return ret; |
| } |
| |
| sctx = scrub_setup_ctx(dev, is_dev_replace); |
| if (IS_ERR(sctx)) { |
| mutex_unlock(&fs_info->scrub_lock); |
| mutex_unlock(&fs_info->fs_devices->device_list_mutex); |
| scrub_workers_put(fs_info); |
| return PTR_ERR(sctx); |
| } |
| sctx->readonly = readonly; |
| dev->scrub_device = 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); |
| |
| if (!is_dev_replace) { |
| /* |
| * 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); |
| } |
| |
| if (!ret) |
| ret = scrub_enumerate_chunks(sctx, dev, start, end, |
| is_dev_replace); |
| |
| 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)); |
| |
| mutex_lock(&fs_info->scrub_lock); |
| dev->scrub_device = NULL; |
| scrub_workers_put(fs_info); |
| mutex_unlock(&fs_info->scrub_lock); |
| |
| scrub_free_ctx(sctx); |
| |
| return ret; |
| } |
| |
| void btrfs_scrub_pause(struct btrfs_root *root) |
| { |
| struct btrfs_fs_info *fs_info = root->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_root *root) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| |
|