dm: introduce a new DM_MAPIO_KILL return value

This untangles the DM_MAPIO_* values returned from ->clone_and_map_rq
from the error codes used by the block layer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
3 files changed