From 7c6d90e2bb1a98b86d73b9e8ab4d97ed5507e37c Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Thu, 16 Jun 2016 18:21:19 +0100 Subject: iommu/io-pgtable-arm: Fix iova_to_phys for block entries The implementation of iova_to_phys for the long-descriptor ARM io-pgtable code always masks with the granule size when inserting the low virtual address bits into the physical address determined from the page tables. In cases where the leaf entry is found before the final level of table (i.e. due to a block mapping), this results in rounding down to the bottom page of the block mapping. Consequently, the physical address range batching in the vfio_unmap_unpin is defeated and we end up taking the long way home. This patch fixes the problem by masking the virtual address with the appropriate mask for the level at which the leaf descriptor is located. The short-descriptor code already gets this right, so no change is needed there. Cc: Reported-by: Robin Murphy Tested-by: Robin Murphy Signed-off-by: Will Deacon diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c index a1ed1b7..f5c90e1 100644 --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -576,7 +576,7 @@ static phys_addr_t arm_lpae_iova_to_phys(struct io_pgtable_ops *ops, return 0; found_translation: - iova &= (ARM_LPAE_GRANULE(data) - 1); + iova &= (ARM_LPAE_BLOCK_SIZE(lvl, data) - 1); return ((phys_addr_t)iopte_to_pfn(pte,data) << data->pg_shift) | iova; } -- cgit v0.10.2