• Ross Zwisler's avatar
    dm: prevent DAX mounts if not supported · dbc62659
    Ross Zwisler authored
    Currently device_supports_dax() just checks to see if the QUEUE_FLAG_DAX
    flag is set on the device's request queue to decide whether or not the
    device supports filesystem DAX.  Really we should be using
    bdev_dax_supported() like filesystems do at mount time.  This performs
    other tests like checking to make sure the dax_direct_access() path works.
    
    We also explicitly clear QUEUE_FLAG_DAX on the DM device's request queue if
    any of the underlying devices do not support DAX.  This makes the handling
    of QUEUE_FLAG_DAX consistent with the setting/clearing of most other flags
    in dm_table_set_restrictions().
    
    Now that bdev_dax_supported() explicitly checks for QUEUE_FLAG_DAX, this
    will ensure that filesystems built upon DM devices will only be able to
    mount with DAX if all underlying devices also support DAX.
    Signed-off-by: default avatarRoss Zwisler <ross.zwisler@linux.intel.com>
    Fixes: commit 545ed20e ("dm: add infrastructure for DAX support")
    Cc: stable@vger.kernel.org
    Acked-by: default avatarDan Williams <dan.j.williams@intel.com>
    Reviewed-by: default avatarToshi Kani <toshi.kani@hpe.com>
    Signed-off-by: default avatarMike Snitzer <snitzer@redhat.com>
    dbc62659
dm-table.c 49.6 KB