From 34f3e4f23ca3d259fe078f62a128d97ca83508ef Mon Sep 17 00:00:00 2001 From: liubo Date: Sat, 6 Aug 2011 08:35:23 +0000 Subject: [PATCH] Btrfs: fix an oops of log replay When btrfs recovers from a crash, it may hit the oops below: ------------[ cut here ]------------ kernel BUG at fs/btrfs/inode.c:4580! [...] RIP: 0010:[] [] btrfs_add_link+0x161/0x1c0 [btrfs] [...] Call Trace: [] ? btrfs_inode_ref_index+0x31/0x80 [btrfs] [] add_inode_ref+0x319/0x3f0 [btrfs] [] replay_one_buffer+0x2c7/0x390 [btrfs] [] walk_down_log_tree+0x32a/0x480 [btrfs] [] walk_log_tree+0xf5/0x240 [btrfs] [] btrfs_recover_log_trees+0x250/0x350 [btrfs] [] ? btrfs_recover_log_trees+0x350/0x350 [btrfs] [] open_ctree+0x1442/0x17d0 [btrfs] [...] This comes from that while replaying an inode ref item, we forget to check those old conflicting DIR_ITEM and DIR_INDEX items in fs/file tree, then we will come to conflict corners which lead to BUG_ON(). Signed-off-by: Liu Bo Tested-by: Andy Lutomirski Signed-off-by: Chris Mason --- fs/btrfs/tree-log.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index babee65f8eda..786639fca067 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -799,14 +799,15 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans, struct extent_buffer *eb, int slot, struct btrfs_key *key) { - struct inode *dir; - int ret; struct btrfs_inode_ref *ref; + struct btrfs_dir_item *di; + struct inode *dir; struct inode *inode; - char *name; - int namelen; unsigned long ref_ptr; unsigned long ref_end; + char *name; + int namelen; + int ret; int search_done = 0; /* @@ -909,6 +910,25 @@ again: } btrfs_release_path(path); + /* look for a conflicting sequence number */ + di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir), + btrfs_inode_ref_index(eb, ref), + name, namelen, 0); + if (di && !IS_ERR(di)) { + ret = drop_one_dir_item(trans, root, path, dir, di); + BUG_ON(ret); + } + btrfs_release_path(path); + + /* look for a conflicing name */ + di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir), + name, namelen, 0); + if (di && !IS_ERR(di)) { + ret = drop_one_dir_item(trans, root, path, dir, di); + BUG_ON(ret); + } + btrfs_release_path(path); + insert: /* insert our name */ ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,