From: David Sterba <dsterba@xxxxxxxx> commit 6819703f5a365c95488b07066a8744841bf14231 upstream. The defrag loop processes leaves in batches and starting transaction for each. The whole defragmentation on a given root is protected by a bit but in case the transaction fails, the bit is not cleared In case the transaction fails the bit would prevent starting defragmentation again, so make sure it's cleared. CC: stable@xxxxxxxxxxxxxxx # 4.4+ Reviewed-by: Qu Wenruo <wqu@xxxxxxxx> Reviewed-by: Anand Jain <anand.jain@xxxxxxxxxx> Signed-off-by: David Sterba <dsterba@xxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/btrfs/transaction.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -1406,8 +1406,10 @@ int btrfs_defrag_root(struct btrfs_root while (1) { trans = btrfs_start_transaction(root, 0); - if (IS_ERR(trans)) - return PTR_ERR(trans); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + break; + } ret = btrfs_defrag_leaves(trans, root);