On Fri, Oct 23, 2015 at 4:11 PM, Jeff Mahoney <je...@suse.com> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On 10/23/15 4:03 AM, Zhao Lei wrote: >> Since we set source bg to readonly in scrub/replace, we don't need >> to consider confliction of no-cow write in scrub/replace operaion. > > What happens if there's a read failure? IIRC the initial purpose of > this code was to correct read failures during scrub and device > replacement by fetching the bad extent from another device if one is > available.
And we don't have xfstests, or any other automated test suite, to test those code paths. So completely useless to run xfstests in a loop for 5 days, especially the generic tests which never trigger scrub runs... > > See commit 0ef8e45158f (btrfs scrub: add fixup code for errors on > nodatasum files) > > - -Jeff > >> This patch removes special code for no-cow mode in scrub/replace, >> reduced 670 lines. >> >> Tested by continuous xfstests in 5 days, include generic and btrfs >> groups with 10 mount options include nodatacow. >> >> Signed-off-by: Zhao Lei <zhao...@cn.fujitsu.com> --- >> fs/btrfs/ctree.h | 1 - fs/btrfs/scrub.c | 669 >> ------------------------------------------------------- 2 files >> changed, 670 deletions(-) >> >> diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index >> 938efe3..3387509 100644 --- a/fs/btrfs/ctree.h +++ >> b/fs/btrfs/ctree.h @@ -1688,7 +1688,6 @@ struct btrfs_fs_info { int >> scrub_workers_refcnt; struct btrfs_workqueue *scrub_workers; struct >> btrfs_workqueue *scrub_wr_completion_workers; - struct >> btrfs_workqueue *scrub_nocow_workers; struct btrfs_workqueue >> *scrub_parity_workers; >> >> #ifdef CONFIG_BTRFS_FS_CHECK_INTEGRITY diff --git >> a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index d64f557..6027679 >> 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -205,32 >> +205,6 @@ struct scrub_ctx { atomic_t refs; }; >> >> -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; @@ >> -242,8 +216,6 >> @@ struct scrub_warning { >> >> 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_block *original_sblock, struct scrub_block >> *sblocks_for_recheck); @@ -298,13 +270,6 @@ static int >> scrub_add_page_to_wr_bio(struct scrub_ctx *sctx, 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_put_ctx(struct scrub_ctx *sctx); @@ -355,60 +320,6 @@ >> static void scrub_blocked_if_needed(struct btrfs_fs_info *fs_info) >> scrub_pause_off(fs_info); } >> >> -/* - * 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; - - >> atomic_inc(&sctx->refs); - /* - * 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); - >> scrub_put_ctx(sctx); -} - static void scrub_free_csums(struct >> scrub_ctx *sctx) { while (!list_empty(&sctx->csum_list)) { @@ >> -686,194 +597,6 @@ out: btrfs_free_path(path); } >> >> -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; - } - ret = repair_io_failure(inode, offset, >> PAGE_SIZE, - fixup->logical, page, - >> offset - >> page_offset(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); -} - static inline void >> scrub_get_recover(struct scrub_recover *recover) { >> atomic_inc(&recover->refs); @@ -940,11 +663,6 @@ static int >> scrub_handle_errored_block(struct scrub_block *sblock_to_check) >> 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 @@ -1058,36 +776,6 >> @@ static int scrub_handle_errored_block(struct scrub_block >> *sblock_to_check) goto out; } >> >> - if (!is_metadata && !have_csum) { - struct >> scrub_fixup_nodatasum >> *fixup_nodatasum; - - WARN_ON(sctx->is_dev_replace); - >> -nodatasum_case: - - /* - * !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, btrfs_scrub_helper, - >> 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. @@ >> -2575,23 +2263,9 @@ static int scrub_extent(struct scrub_ctx *sctx, >> u64 logical, u64 len, 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; @@ -3762,10 >> +3436,6 @@ static noinline_for_stack int scrub_workers_get(struct >> btrfs_fs_info *fs_info, if (!fs_info->scrub_wr_completion_workers) >> goto fail_scrub_wr_completion_workers; >> >> - fs_info->scrub_nocow_workers = - >> btrfs_alloc_workqueue("btrfs-scrubnc", flags, 1, 0); - if >> (!fs_info->scrub_nocow_workers) - goto >> fail_scrub_nocow_workers; >> fs_info->scrub_parity_workers = >> btrfs_alloc_workqueue("btrfs-scrubparity", flags, max_active, 2); >> @@ -3776,8 +3446,6 @@ static noinline_for_stack int >> scrub_workers_get(struct btrfs_fs_info *fs_info, return 0; >> >> fail_scrub_parity_workers: - >> btrfs_destroy_workqueue(fs_info->scrub_nocow_workers); >> -fail_scrub_nocow_workers: >> btrfs_destroy_workqueue(fs_info->scrub_wr_completion_workers); >> fail_scrub_wr_completion_workers: >> btrfs_destroy_workqueue(fs_info->scrub_workers); @@ -3790,7 +3458,6 >> @@ 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); >> btrfs_destroy_workqueue(fs_info->scrub_parity_workers); } >> WARN_ON(fs_info->scrub_workers_refcnt < 0); @@ -4081,339 +3748,3 @@ >> static void scrub_free_wr_ctx(struct scrub_wr_ctx *wr_ctx) >> mutex_unlock(&wr_ctx->wr_lock); } >> >> -static int copy_nocow_pages(struct scrub_ctx *sctx, u64 logical, >> u64 len, - int mirror_num, u64 >> physical_for_dev_replace) -{ - >> struct scrub_copy_nocow_ctx *nocow_ctx; - struct btrfs_fs_info >> *fs_info = sctx->dev_root->fs_info; - - nocow_ctx = >> kzalloc(sizeof(*nocow_ctx), GFP_NOFS); - if (!nocow_ctx) { - >> spin_lock(&sctx->stat_lock); - sctx->stat.malloc_errors++; - >> spin_unlock(&sctx->stat_lock); - return -ENOMEM; - } - - >> scrub_pending_trans_workers_inc(sctx); - - nocow_ctx->sctx = sctx; >> - nocow_ctx->logical = logical; - nocow_ctx->len = len; - >> nocow_ctx->mirror_num = mirror_num; - >> nocow_ctx->physical_for_dev_replace = physical_for_dev_replace; - >> btrfs_init_work(&nocow_ctx->work, btrfs_scrubnc_helper, - >> copy_nocow_pages_worker, NULL, NULL); - >> INIT_LIST_HEAD(&nocow_ctx->inodes); - >> btrfs_queue_work(fs_info->scrub_nocow_workers, - >> &nocow_ctx->work); - - return 0; -} - -static int >> record_inode_for_nocow(u64 inum, u64 offset, u64 root, void *ctx) >> -{ - struct scrub_copy_nocow_ctx *nocow_ctx = ctx; - struct >> scrub_nocow_inode *nocow_inode; - - nocow_inode = >> kzalloc(sizeof(*nocow_inode), GFP_NOFS); - if (!nocow_inode) - >> return -ENOMEM; - nocow_inode->inum = inum; - nocow_inode->offset = >> offset; - nocow_inode->root = root; - >> list_add_tail(&nocow_inode->list, &nocow_ctx->inodes); - return 0; >> -} - -#define COPY_COMPLETE 1 - -static void >> copy_nocow_pages_worker(struct btrfs_work *work) -{ - struct >> scrub_copy_nocow_ctx *nocow_ctx = - container_of(work, struct >> scrub_copy_nocow_ctx, work); - struct scrub_ctx *sctx = >> nocow_ctx->sctx; - u64 logical = nocow_ctx->logical; - u64 len = >> nocow_ctx->len; - int mirror_num = nocow_ctx->mirror_num; - u64 >> physical_for_dev_replace = nocow_ctx->physical_for_dev_replace; - >> int ret; - struct btrfs_trans_handle *trans = NULL; - struct >> btrfs_fs_info *fs_info; - struct btrfs_path *path; - struct >> btrfs_root *root; - int not_written = 0; - - fs_info = >> sctx->dev_root->fs_info; - root = fs_info->extent_root; - - path = >> btrfs_alloc_path(); - if (!path) { - spin_lock(&sctx->stat_lock); >> - sctx->stat.malloc_errors++; - >> spin_unlock(&sctx->stat_lock); - >> not_written = 1; - goto out; - } - - trans = >> btrfs_join_transaction(root); - if (IS_ERR(trans)) { - >> not_written >> = 1; - goto out; - } - - ret = >> iterate_inodes_from_logical(logical, fs_info, path, - >> record_inode_for_nocow, nocow_ctx); - if (ret != 0 && ret != >> -ENOENT) { - btrfs_warn(fs_info, "iterate_inodes_from_logical() >> failed: log %llu, " - "phys %llu, len %llu, mir %u, ret %d", >> - >> logical, physical_for_dev_replace, len, mirror_num, - ret); - >> not_written = 1; - goto out; - } - - >> btrfs_end_transaction(trans, >> root); - trans = NULL; - while (!list_empty(&nocow_ctx->inodes)) { >> - struct scrub_nocow_inode *entry; - entry = >> list_first_entry(&nocow_ctx->inodes, - >> struct >> scrub_nocow_inode, - list); - >> list_del_init(&entry->list); - >> ret = copy_nocow_pages_for_inode(entry->inum, entry->offset, - >> entry->root, nocow_ctx); - kfree(entry); - if (ret == >> COPY_COMPLETE) { - ret = 0; - break; >> - } else if (ret) { - >> break; - } - } -out: - while >> (!list_empty(&nocow_ctx->inodes)) { - >> struct scrub_nocow_inode *entry; - entry = >> list_first_entry(&nocow_ctx->inodes, - >> struct >> scrub_nocow_inode, - list); - >> list_del_init(&entry->list); - >> kfree(entry); - } - if (trans && !IS_ERR(trans)) - >> btrfs_end_transaction(trans, root); - if (not_written) - >> btrfs_dev_replace_stats_inc(&fs_info->dev_replace. - >> num_uncorrectable_read_errors); - - btrfs_free_path(path); - >> kfree(nocow_ctx); - - scrub_pending_trans_workers_dec(sctx); -} - >> -static int check_extent_to_block(struct inode *inode, u64 start, >> u64 len, - u64 logical) -{ - struct >> extent_state *cached_state >> = NULL; - struct btrfs_ordered_extent *ordered; - struct >> extent_io_tree *io_tree; - struct extent_map *em; - u64 lockstart = >> start, lockend = start + len - 1; - int ret = 0; - - io_tree = >> &BTRFS_I(inode)->io_tree; - - lock_extent_bits(io_tree, lockstart, >> lockend, 0, &cached_state); - ordered = >> btrfs_lookup_ordered_range(inode, lockstart, len); - if (ordered) >> { - btrfs_put_ordered_extent(ordered); - ret = 1; - >> goto >> out_unlock; - } - - em = btrfs_get_extent(inode, NULL, 0, start, >> len, 0); - if (IS_ERR(em)) { - ret = PTR_ERR(em); - >> goto >> out_unlock; - } - - /* - * This extent does not actually cover the >> logical extent anymore, - * move on to the next inode. - */ - if >> (em->block_start > logical || - em->block_start + em->block_len >> < logical + len) { - free_extent_map(em); - ret = 1; - >> goto >> out_unlock; - } - free_extent_map(em); - -out_unlock: - >> unlock_extent_cached(io_tree, lockstart, lockend, &cached_state, - >> GFP_NOFS); - return ret; -} - -static int >> copy_nocow_pages_for_inode(u64 inum, u64 offset, u64 root, - >> struct scrub_copy_nocow_ctx *nocow_ctx) -{ - struct btrfs_fs_info >> *fs_info = nocow_ctx->sctx->dev_root->fs_info; - struct btrfs_key >> key; - struct inode *inode; - struct page *page; - struct >> btrfs_root *local_root; - struct extent_io_tree *io_tree; - u64 >> physical_for_dev_replace; - u64 nocow_ctx_logical; - u64 len = >> nocow_ctx->len; - unsigned long index; - int srcu_index; - int ret >> = 0; - int err = 0; - - key.objectid = root; - key.type = >> BTRFS_ROOT_ITEM_KEY; - key.offset = (u64)-1; - - 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); - - /* Avoid >> truncate/dio/punch hole.. */ - mutex_lock(&inode->i_mutex); - >> inode_dio_wait(inode); - - physical_for_dev_replace = >> nocow_ctx->physical_for_dev_replace; - io_tree = >> &BTRFS_I(inode)->io_tree; - nocow_ctx_logical = >> nocow_ctx->logical; - - ret = check_extent_to_block(inode, offset, >> len, nocow_ctx_logical); - if (ret) { - ret = ret > 0 ? 0 : >> ret; - >> goto out; - } - - while (len >= PAGE_CACHE_SIZE) { - index = >> offset >> PAGE_CACHE_SHIFT; -again: - page = >> find_or_create_page(inode->i_mapping, index, GFP_NOFS); - if >> (!page) { - btrfs_err(fs_info, "find_or_create_page() >> failed"); - >> ret = -ENOMEM; - goto out; - } - - >> if (PageUptodate(page)) { - >> if (PageDirty(page)) - goto next_page; - >> } else { - >> ClearPageError(page); - err = >> extent_read_full_page(io_tree, >> page, - >> btrfs_get_extent, - >> nocow_ctx->mirror_num); - if (err) { - >> ret = err; - goto >> next_page; - } - - lock_page(page); - >> /* - * If the page >> has been remove from the page cache, - * the data on >> it is >> meaningless, because it may be - * old one, the new >> data may be >> written into the new - * page in the page cache. - >> */ - if >> (page->mapping != inode->i_mapping) { - >> unlock_page(page); - >> page_cache_release(page); - goto again; - >> } - if >> (!PageUptodate(page)) { - ret = -EIO; - >> goto next_page; - >> } - } - - ret = check_extent_to_block(inode, offset, >> len, - >> nocow_ctx_logical); - if (ret) { - ret = ret > 0 >> ? 0 : ret; - >> goto next_page; - } - - err = >> write_page_nocow(nocow_ctx->sctx, - >> physical_for_dev_replace, page); - if (err) - >> ret = err; >> -next_page: - unlock_page(page); - >> page_cache_release(page); - - >> if (ret) - break; - - offset += >> PAGE_CACHE_SIZE; - >> physical_for_dev_replace += PAGE_CACHE_SIZE; - >> nocow_ctx_logical >> += PAGE_CACHE_SIZE; - len -= PAGE_CACHE_SIZE; - } - ret = >> COPY_COMPLETE; -out: - mutex_unlock(&inode->i_mutex); - >> iput(inode); - return ret; -} - -static int write_page_nocow(struct >> scrub_ctx *sctx, - u64 physical_for_dev_replace, >> struct page >> *page) -{ - struct bio *bio; - struct btrfs_device *dev; - int >> ret; - - dev = sctx->wr_ctx.tgtdev; - if (!dev) - return >> -EIO; - >> if (!dev->bdev) { - printk_ratelimited(KERN_WARNING - >> "BTRFS: >> scrub write_page_nocow(bdev == NULL) is unexpected!\n"); - return >> -EIO; - } - bio = btrfs_io_bio_alloc(GFP_NOFS, 1); - if >> (!bio) { - >> spin_lock(&sctx->stat_lock); - sctx->stat.malloc_errors++; - >> spin_unlock(&sctx->stat_lock); - return -ENOMEM; - } - >> bio->bi_iter.bi_size = 0; - bio->bi_iter.bi_sector = >> physical_for_dev_replace >> 9; - bio->bi_bdev = dev->bdev; - ret = >> bio_add_page(bio, page, PAGE_CACHE_SIZE, 0); - if (ret != >> PAGE_CACHE_SIZE) { -leave_with_eio: - bio_put(bio); - >> btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS); - >> return -EIO; - } - - if (btrfsic_submit_bio_wait(WRITE_SYNC, bio)) >> - goto leave_with_eio; - - bio_put(bio); - return 0; -} >> > > > - -- > Jeff Mahoney > SUSE Labs > -----BEGIN PGP SIGNATURE----- > Version: GnuPG/MacGPG2 v2.0.19 (Darwin) > > iQIcBAEBAgAGBQJWKk4SAAoJEB57S2MheeWyVwkP/0jftdMvTiXNe+7pzcnyoimA > lYDb0pXTE+/F7utsRMFN1z/NHMLJaTzfmeBVffG+FlEPKakzsXqfTKuQ1MO3F+NK > m8djSfGd88rQFfIU3kdhw3g+3LIp4JG10/IMKjESS7ra4zFymIOrHAuK9JxsqCO5 > VQ4f6rgqpeXGfi3F3huS6JVhDJJrXQcNCgbwUbNajzM052AsOsxfxUj7cLERgJ9Q > 72GyA+cNstMMoHb5XqR3P+LlYdBJmQTQBnYSMP55WY+jZy6Eyt969Tkwr+T+S7j1 > s6PePS7ak8sZNpXhLxMtipIPF7b764iMTZrauf4uqa7woO4cAq5b/El+CvYrJA4B > fgxHRyCAJVdJrmdJuFP/ddY4OzzWByXyoT2cvv8+eysAUlRxrYB4/lE5FfDxUhC0 > wwUDruFbk27pYdCZNxnLkJ8oMaJLaYjcNSu5jgD3omNmWOSa6ZN17Ha7VPtLLA4W > jUZXy/k4J4wKTR+/BfpsE52wcSEgFT6C3n+2A+y+/tS10fTw2UgTW3SwiYZlmYHi > amDXa8NcbrMNaZql1ykzkIpKHfkkNNScZTI8u4GWyVCs30npf8YOOmBNVRshp5WQ > BnBPqgHcJFw+5autuBrtw58Z1j8IVlGdASt1d/VcBmgMJPCvIm/U/YfBHXslcUHU > MNOl/0NrfnfAdRZbAFeL > =wNWX > -----END PGP SIGNATURE----- > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Filipe David Manana, "Reasonable men adapt themselves to the world. Unreasonable men adapt the world to themselves. That's why all progress depends on unreasonable men." -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html