From e81e99bacc9f9347bda7808a949c1ce9fcc2bbf4 Mon Sep 17 00:00:00 2001 From: David Stevens Date: Wed, 29 Sep 2021 11:32:59 +0900 Subject: swiotlb: Support aligned swiotlb buffers Add an argument to swiotlb_tbl_map_single that specifies the desired alignment of the allocated buffer. This is used by dma-iommu to ensure the buffer is aligned to the iova granule size when using swiotlb with untrusted sub-granule mappings. This addresses an issue where adjacent slots could be exposed to the untrusted device if IO_TLB_SIZE < iova granule < PAGE_SIZE. Signed-off-by: David Stevens Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20210929023300.335969-7-stevensd@google.com Signed-off-by: Joerg Roedel --- drivers/iommu/dma-iommu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 85a005b268f6..289c49ead01a 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -818,8 +818,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, size_t padding_size; aligned_size = iova_align(iovad, size); - phys = swiotlb_tbl_map_single(dev, phys, size, - aligned_size, dir, attrs); + phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size, + iova_mask(iovad), dir, attrs); if (phys == DMA_MAPPING_ERROR) return DMA_MAPPING_ERROR; -- cgit