Commit 6ac7dffe authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Will Deacon
Browse files

iommu: Add a kdoc to iommu_unmap() 



Describe the most conservative version of the driver implementations.
All drivers should support this.

Many drivers support extending the range if a large page is hit, but
let's not make that officially approved API. The main point is to
document explicitly that split is not supported.

Reviewed-by: default avatarLiviu Dudau <liviu.dudau@arm.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/3-v3-b3a5b5937f56+7bb-arm_no_split_jgg@nvidia.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent fd506516

drivers/iommu/iommu.c

+14 −0
Original line number Diff line number Diff line
@@ -2586,6 +2586,20 @@ static size_t __iommu_unmap(struct iommu_domain *domain, 
	return unmapped;

}



/**

 * iommu_unmap() - Remove mappings from a range of IOVA

 * @domain: Domain to manipulate

 * @iova: IO virtual address to start

 * @size: Length of the range starting from @iova

 *

 * iommu_unmap() will remove a translation created by iommu_map(). It cannot

 * subdivide a mapping created by iommu_map(), so it should be called with IOVA

 * ranges that match what was passed to iommu_map(). The range can aggregate

 * contiguous iommu_map() calls so long as no individual range is split.

 *

 * Returns: Number of bytes of IOVA unmapped. iova + res will be the point

 * unmapping stopped.

 */

size_t iommu_unmap(struct iommu_domain *domain,

		   unsigned long iova, size_t size)

{