Commit a2cc11db authored Sep 08, 2014 by Filipe Manana Committed by Chris Mason Sep 17, 2014

Btrfs: fix directory recovery from fsync log



When replaying a directory from the fsync log, if a directory entry
exists both in the fs/subvol tree and in the log, the directory's inode
got its i_size updated incorrectly, accounting for the dentry's name
twice.

Reproducer, from a test for xfstests:

    _scratch_mkfs >> $seqres.full 2>&1
    _init_flakey
    _mount_flakey

    touch $SCRATCH_MNT/foo
    sync

    touch $SCRATCH_MNT/bar
    xfs_io -c "fsync" $SCRATCH_MNT
    xfs_io -c "fsync" $SCRATCH_MNT/bar

    _load_flakey_table $FLAKEY_DROP_WRITES
    _unmount_flakey

    _load_flakey_table $FLAKEY_ALLOW_WRITES
    _mount_flakey

    [ -f $SCRATCH_MNT/foo ] || echo "file foo is missing"
    [ -f $SCRATCH_MNT/bar ] || echo "file bar is missing"

    _unmount_flakey
    _check_scratch_fs $FLAKEY_DEV

The filesystem check at the end failed with the message:
"root 5 root dir 256 error".

A test case for xfstests follows.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>

parent 25ce459c

fs/btrfs/tree-log.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1637,6 +1637,7 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans,
		found_key.type == log_key.type &&
		found_key.offset == log_key.offset &&
		btrfs_dir_type(path->nodes[0], dst_di) == log_type) {
		update_size = false;
		goto out;
		}