From: Leon Romanovsky <leonro@xxxxxxxxxx> Add kernel-doc section for iommu_unmap and iommu_unmap_fast to document existing limitation of underlying functions which can't split individual ranges. Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Acked-by: Will Deacon <will@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxx> --- drivers/iommu/iommu.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index ec75d14497bf..c86a57abe292 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2590,6 +2590,25 @@ size_t iommu_unmap(struct iommu_domain *domain, } EXPORT_SYMBOL_GPL(iommu_unmap); +/** + * iommu_unmap_fast() - Remove mappings from a range of IOVA without IOTLB sync + * @domain: Domain to manipulate + * @iova: IO virtual address to start + * @size: Length of the range starting from @iova + * @iotlb_gather: range information for a pending IOTLB flush + * + * iommu_unmap_fast() will remove a translation created by iommu_map(). + * It can't 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. + * + * Basically iommu_unmap_fast() is the same as iommu_unmap() but for callers + * which manage the IOTLB flushing externally to perform a batched sync. + * + * Returns: Number of bytes of IOVA unmapped. iova + res will be the point + * unmapping stopped. + */ size_t iommu_unmap_fast(struct iommu_domain *domain, unsigned long iova, size_t size, struct iommu_iotlb_gather *iotlb_gather) -- 2.47.0
