dma: add calls for dma_map_page_attrs and dma_unmap_page_attrs
authorAlexander Duyck <alexander.h.duyck@intel.com>
Wed, 14 Dec 2016 23:05:23 +0000 (15:05 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 15 Dec 2016 00:04:08 +0000 (16:04 -0800)
commit0495c3d367944e4af053983ff3cdf256b567b053
tree7d7418b6377cc4a8d6db54bcd9da8d40e998bf45
parent4bfa135abec99f4b35b5636f56a6db75ce3c64d7
dma: add calls for dma_map_page_attrs and dma_unmap_page_attrs

Add support for mapping and unmapping a page with attributes.

The primary use for this is currently to allow for us to pass the
DMA_ATTR_SKIP_CPU_SYNC attribute when mapping and unmapping a page.  On
some architectures such as ARM the synchronization has significant
overhead and if we are already taking care of the sync_for_cpu and
sync_for_device from the driver there isn't much need to handle this in
the map/unmap calls as well.

Link: http://lkml.kernel.org/r/20161110113601.76501.46095.stgit@ahduyck-blue-test.jf.intel.com
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
include/linux/dma-mapping.h