path: root/cmds-check.c
diff options
authorQu Wenruo <>2014-12-09 16:27:24 +0800
committerDavid Sterba <>2014-12-10 11:55:17 +0100
commited3a206c8f4d71469db5899a5a4d6659b315489e (patch)
treee951f435cb2c4cf2f1cb108a4c05ecbedc9ac0bc /cmds-check.c
parent378eacf815893cad989463b0917dcd2dd6553438 (diff)
btrfs-progs: Record highest inode number before repair.
Record highest inode number before inode repair. This is especially important for corrupted leaf case. Under that case, if use btrfs_find_free_objectid, it may find a ino existing in corrupted leaf but dropped by btree_recover. If that happens, created dir will be referenced incorrectly since there may be inode_ref or dir_index/item refers to it. So we must record the highest inode number according to the inode_cache. Inode_cache is OK since when a inode_ref or dir_index/item is found even the referenced source is not found, it will be created. If we record the highest inode number of inode_cache, and use highest_inode + 1 as 'lost+found' dir, it will ensure the newly created dir not conflicting with any possible inode. This provides the basis for nlink or inode rebuild for repairing btrfs with leaf/node corruption. Signed-off-by: Qu Wenruo <> Signed-off-by: David Sterba <>
Diffstat (limited to 'cmds-check.c')
1 files changed, 15 insertions, 0 deletions
diff --git a/cmds-check.c b/cmds-check.c
index d57363c1..3d3d8d79 100644
--- a/cmds-check.c
+++ b/cmds-check.c
@@ -1927,6 +1927,21 @@ static int check_inode_recs(struct btrfs_root *root,
+ * We need to record the highest inode number for later 'lost+found'
+ * dir creation.
+ * We must select a ino not used/refered by any existing inode, or
+ * 'lost+found' ino may be a missing ino in a corrupted leaf,
+ * this may cause 'lost+found' dir has wrong nlinks.
+ */
+ cache = last_cache_extent(inode_cache);
+ if (cache) {
+ node = container_of(cache, struct ptr_node, cache);
+ rec = node->data;
+ if (rec->ino > root->highest_inode)
+ root->highest_inode = rec->ino;
+ }
+ /*
* We need to repair backrefs first because we could change some of the
* errors in the inode recs.