From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cn.fujitsu.com ([222.73.24.84]:53791 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751060AbcDZDtl (ORCPT ); Mon, 25 Apr 2016 23:49:41 -0400 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz, Lu Fengqi Subject: [PATCH RFC 05/16] btrfs-progs: fsck: Introduce function to check shared block ref Date: Tue, 26 Apr 2016 11:48:52 +0800 Message-Id: <1461642543-4621-6-git-send-email-quwenruo@cn.fujitsu.com> In-Reply-To: <1461642543-4621-1-git-send-email-quwenruo@cn.fujitsu.com> References: <1461642543-4621-1-git-send-email-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 Sender: linux-btrfs-owner@vger.kernel.org List-ID: From: Lu Fengqi Introduce function check_shared_block_backref() to check shared block ref. Signed-off-by: Lu Fengqi Signed-off-by: Qu Wenruo --- cmds-check.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) diff --git a/cmds-check.c b/cmds-check.c index 81dd4f3..1d1b198 100644 --- a/cmds-check.c +++ b/cmds-check.c @@ -8831,6 +8831,48 @@ out: return -err; } +/* + * Check referencer for shared block backref + * If level == -1, this function will resolve the level. + */ +static int check_shared_block_backref(struct btrfs_fs_info *fs_info, + u64 parent, u64 bytenr, int level) +{ + struct extent_buffer *eb; + u32 nodesize = btrfs_super_nodesize(fs_info->super_copy); + u32 nr; + int found_parent = 0; + int i; + + eb = read_tree_block_fs_info(fs_info, parent, nodesize, 0); + if (!extent_buffer_uptodate(eb)) + goto out; + + if (level == -1) + level = query_tree_block_level(fs_info, bytenr); + if (level < 0) + goto out; + + if (level + 1 != btrfs_header_level(eb)) + goto out; + + nr = btrfs_header_nritems(eb); + for (i = 0; i < nr; i++) { + if (bytenr == btrfs_node_blockptr(eb, i)) { + found_parent = 1; + break; + } + } +out: + free_extent_buffer(eb); + if (!found_parent) { + error("Shared extent[%llu %u] lost its parent(parent: %llu, level: %u)", + bytenr, nodesize, parent, level); + return -MISSING_REFERENCER; + } + return 0; +} + static int btrfs_fsck_reinit_root(struct btrfs_trans_handle *trans, struct btrfs_root *root, int overwrite) { -- 2.8.0