Pages allocated using the DMA API have a coherent memory mapping. Make
this mapping visible to drivers so they can decide to use it instead of
creating their own redundant one.
Signed-off-by: NAlexandre Courbot <acourbot@nvidia.com>
Acked-by: NDavid Airlie <airlied@linux.ie>
Signed-off-by: NBen Skeggs <bskeggs@redhat.com>