diff options
| -rw-r--r-- | cmds-check.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/cmds-check.c b/cmds-check.c index 84890f3d..8c2ff3f9 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -8860,6 +8860,82 @@ error: return err; } +/* + * Get real tree block level for the case like shared block + * Return >= 0 as tree level + * Return <0 for error + */ +static int query_tree_block_level(struct btrfs_fs_info *fs_info, u64 bytenr) +{ + struct extent_buffer *eb; + struct btrfs_path path; + struct btrfs_key key; + struct btrfs_extent_item *ei; + u64 flags; + u64 transid; + u32 nodesize = btrfs_super_nodesize(fs_info->super_copy); + u8 backref_level; + u8 header_level; + int ret; + + /* Search extent tree for extent generation and level */ + key.objectid = bytenr; + key.type = BTRFS_METADATA_ITEM_KEY; + key.offset = (u64)-1; + + btrfs_init_path(&path); + ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, &path, 0, 0); + if (ret < 0) + goto release_out; + ret = btrfs_previous_extent_item(fs_info->extent_root, &path, bytenr); + if (ret < 0) + goto release_out; + if (ret > 0) { + ret = -ENOENT; + goto release_out; + } + + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); + ei = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_extent_item); + flags = btrfs_extent_flags(path.nodes[0], ei); + if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) { + ret = -ENOENT; + goto release_out; + } + + /* Get transid for later read_tree_block() check */ + transid = btrfs_extent_generation(path.nodes[0], ei); + + /* Get backref level as one source */ + if (key.type == BTRFS_METADATA_ITEM_KEY) { + backref_level = key.offset; + } else { + struct btrfs_tree_block_info *info; + + info = (struct btrfs_tree_block_info *)(ei + 1); + backref_level = btrfs_tree_block_level(path.nodes[0], info); + } + btrfs_release_path(&path); + + /* Get level from tree block as an alternative source */ + eb = read_tree_block_fs_info(fs_info, bytenr, nodesize, transid); + if (!extent_buffer_uptodate(eb)) { + free_extent_buffer(eb); + return -EIO; + } + header_level = btrfs_header_level(eb); + free_extent_buffer(eb); + + if (header_level != backref_level) + return -EIO; + return header_level; + +release_out: + btrfs_release_path(&path); + return ret; +} + static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, int overwrite) { |