From 17d217fe970d34720f4f1633dca73a6aa2f3d9d1 Mon Sep 17 00:00:00 2001 From: Yan Zheng Date: Fri, 12 Dec 2008 10:03:38 -0500 Subject: Btrfs: fix nodatasum handling in balancing code Checksums on data can be disabled by mount option, so it's possible some data extents don't have checksums or have invalid checksums. This causes trouble for data relocation. This patch contains following things to make data relocation work. 1) make nodatasum/nodatacow mount option only affects new files. Checksums and COW on data are only controlled by the inode flags. 2) check the existence of checksum in the nodatacow checker. If checksums exist, force COW the data extent. This ensure that checksum for a given block is either valid or does not exist. 3) update data relocation code to properly handle the case of checksum missing. Signed-off-by: Yan Zheng --- fs/btrfs/file-item.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 111 insertions(+), 3 deletions(-) (limited to 'fs/btrfs/file-item.c') diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 3ebef871ee6c..df0447632dbd 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -140,6 +140,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, return ret; } + int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode, struct bio *bio, u32 *dst) { @@ -185,9 +186,16 @@ int btrfs_lookup_bio_sums(struct btrfs_root *root, struct inode *inode, if (ret == -ENOENT || ret == -EFBIG) ret = 0; sum = 0; - printk("no csum found for inode %lu start " - "%llu\n", inode->i_ino, - (unsigned long long)offset); + if (BTRFS_I(inode)->root->root_key.objectid == + BTRFS_DATA_RELOC_TREE_OBJECTID) { + set_extent_bits(io_tree, offset, + offset + bvec->bv_len - 1, + EXTENT_NODATASUM, GFP_NOFS); + } else { + printk("no csum found for inode %lu " + "start %llu\n", inode->i_ino, + (unsigned long long)offset); + } item = NULL; btrfs_release_path(root, path); goto found; @@ -228,6 +236,106 @@ found: return 0; } +int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end, + struct list_head *list) +{ + struct btrfs_key key; + struct btrfs_path *path; + struct extent_buffer *leaf; + struct btrfs_ordered_sum *sums; + struct btrfs_sector_sum *sector_sum; + struct btrfs_csum_item *item; + unsigned long offset; + int ret; + size_t size; + u64 csum_end; + u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy); + + path = btrfs_alloc_path(); + BUG_ON(!path); + + key.objectid = BTRFS_EXTENT_CSUM_OBJECTID; + key.offset = start; + key.type = BTRFS_EXTENT_CSUM_KEY; + + ret = btrfs_search_slot(NULL, root->fs_info->csum_root, + &key, path, 0, 0); + if (ret < 0) + goto fail; + if (ret > 0 && path->slots[0] > 0) { + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1); + if (key.objectid == BTRFS_EXTENT_CSUM_OBJECTID && + key.type == BTRFS_EXTENT_CSUM_KEY) { + offset = (start - key.offset) >> + root->fs_info->sb->s_blocksize_bits; + if (offset * csum_size < + btrfs_item_size_nr(leaf, path->slots[0] - 1)) + path->slots[0]--; + } + } + + while (start <= end) { + leaf = path->nodes[0]; + if (path->slots[0] >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root->fs_info->csum_root, path); + if (ret < 0) + goto fail; + if (ret > 0) + break; + leaf = path->nodes[0]; + } + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.objectid != BTRFS_EXTENT_CSUM_OBJECTID || + key.type != BTRFS_EXTENT_CSUM_KEY) + break; + + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + if (key.offset > end) + break; + + if (key.offset > start) + start = key.offset; + + size = btrfs_item_size_nr(leaf, path->slots[0]); + csum_end = key.offset + (size / csum_size) * root->sectorsize; + + size = min(csum_end, end + 1) - start; + sums = kzalloc(btrfs_ordered_sum_size(root, size), GFP_NOFS); + BUG_ON(!sums); + + sector_sum = sums->sums; + sums->bytenr = start; + sums->len = size; + + offset = (start - key.offset) >> + root->fs_info->sb->s_blocksize_bits; + offset *= csum_size; + + item = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_csum_item); + while (size > 0) { + read_extent_buffer(path->nodes[0], §or_sum->sum, + ((unsigned long)item) + offset, + csum_size); + sector_sum->bytenr = start; + + size -= root->sectorsize; + start += root->sectorsize; + offset += csum_size; + sector_sum++; + } + list_add_tail(&sums->list, list); + + path->slots[0]++; + } + ret = 0; +fail: + btrfs_free_path(path); + return ret; +} + int btrfs_csum_one_bio(struct btrfs_root *root, struct inode *inode, struct bio *bio, u64 file_start, int contig) { -- cgit v1.2.3