• Yan Zheng's avatar
    Btrfs: fix nodatasum handling in balancing code · 17d217fe
    Yan Zheng authored
    Checksums on data can be disabled by mount option, so it's
    possible some data extents don't have checksums or have
    invalid checksums. This causes trouble for data relocation.
    This patch contains following things to make data relocation
    1) make nodatasum/nodatacow mount option only affects new
    files. Checksums and COW on data are only controlled by the
    inode flags.
    2) check the existence of checksum in the nodatacow checker.
    If checksums exist, force COW the data extent. This ensure that
    checksum for a given block is either valid or does not exist.
    3) update data relocation code to properly handle the case
    of checksum missing.
    Signed-off-by: default avatarYan Zheng <zheng.yan@oracle.com>