• Mike Snitzer's avatar
    dm: add WRITE SAME support · 23508a96
    Mike Snitzer authored
    
    
    WRITE SAME bios have a payload that contain a single page.  When
    cloning WRITE SAME bios DM has no need to modify the bi_io_vec
    attributes (and doing so would be detrimental).  DM need only alter the
    start and end of the WRITE SAME bio accordingly.
    
    Rather than duplicate __clone_and_map_discard, factor out a common
    function that is also used by __clone_and_map_write_same.
    Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
    Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
    23508a96