This iommu_op can tell if domain have a specific capability, like snooping
control for Intel IOMMU, which can be used by other components of kernel to
adjust the behaviour.
Signed-off-by: NSheng Yang <sheng@linux.intel.com>
Signed-off-by: NDavid Woodhouse <David.Woodhouse@intel.com>

This API can be used by KVM for accessing different types of IOMMUs to
do device passthrough to guests. Beside that this API can also be used
by device drivers to map non-linear host memory into dma-linear
addresses to prevent sgather-gather DMA. UIO may be another user for
this API.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>