From: ethanwu <[email protected]> commit cfc0eed0ec89db7c4a8d461174cabfaa4a0912c7 upstream.
We could have some nodes/leaves in subvolume whose owner are not the that subvolume. In this way, when we resolve normal backrefs of that subvolume, we should avoid collecting those references from these blocks. Reviewed-by: Josef Bacik <[email protected]> Reviewed-by: Johannes Thumshirn <[email protected]> Signed-off-by: ethanwu <[email protected]> Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/btrfs/backref.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -443,11 +443,14 @@ static int add_all_parents(struct btrfs_ * slot == nritems. * 2. We are searching for normal backref but bytenr of this leaf * matches shared data backref + * 3. The leaf owner is not equal to the root we are searching + * * For these cases, go to the next leaf before we continue. */ eb = path->nodes[0]; if (path->slots[0] >= btrfs_header_nritems(eb) || - is_shared_data_backref(preftrees, eb->start)) { + is_shared_data_backref(preftrees, eb->start) || + ref->root_id != btrfs_header_owner(eb)) { if (time_seq == SEQ_LAST) ret = btrfs_next_leaf(root, path); else @@ -466,9 +469,12 @@ static int add_all_parents(struct btrfs_ /* * We are searching for normal backref but bytenr of this leaf - * matches shared data backref. + * matches shared data backref, OR + * the leaf owner is not equal to the root we are searching for */ - if (slot == 0 && is_shared_data_backref(preftrees, eb->start)) { + if (slot == 0 && + (is_shared_data_backref(preftrees, eb->start) || + ref->root_id != btrfs_header_owner(eb))) { if (time_seq == SEQ_LAST) ret = btrfs_next_leaf(root, path); else
