iommu: Implement common IOMMU ops for DMA mapping
Taking inspiration from the existing arch/arm code, break out some
generic functions to interface the DMA-API to the IOMMU-API. This will
do the bulk of the heavy lifting for IOMMU-backed dma-mapping.
Since associating an IOVA allocator with an IOMMU domain is a fairly
common need, rather than introduce yet another private structure just to
do this for ourselves, extend the top-level struct iommu_domain with the
notion. A simple opaque cookie allows reuse by other IOMMU API users
with their various different incompatible allocator types.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index f9c1b6d..f174506 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -81,6 +81,7 @@
iommu_fault_handler_t handler;
void *handler_token;
struct iommu_domain_geometry geometry;
+ void *iova_cookie;
};
enum iommu_cap {