Commit 27e7a6ba authored Mar 04, 2015 by Mitchel Humpherys Committed by Matt Wagantall May 30, 2015

iommu/arm-smmu: fix leak in arm_smmu_flush_pgtable



We're currently mapping a page in arm_smmu_flush_pgtable without ever
unmapping it.  Fix this by calling dma_unmap_page on the returned dma
address.  Since the only reason we're calling dma_map_page is to make
sure it actually gets flushed out to RAM, we can just call
dma_unmap_page immediately following the map.

Without this, eventually swiotlb runs out of memory and starts printing
things like:

    arm-smmu d00000.arm,smmu: swiotlb buffer is full (sz: 128 bytes)

Change-Id: I69421de6e2189a16cd88f225e2698cd88d669dff
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>

parent e491deea

drivers/iommu/arm-smmu.c

+13 −4

Original line number	Diff line number	Diff line
		@@ -978,13 +978,22 @@ static void arm_smmu_flush_pgtable(struct arm_smmu_domain *smmu_domain,
		* recursion here as the SMMU table walker will not be wired
		* through another SMMU.
		*/
		if (smmu)
		if (smmu) {
		dma_addr_t handle =
		dma_map_page(smmu->dev, virt_to_page(addr),
		offset, size, DMA_TO_DEVICE);
		if (handle == DMA_ERROR_CODE)
		dev_err(smmu->dev,
		"Couldn't flush page tables at %p!\n",
		addr);
		else
		dma_unmap_page(smmu->dev, handle, size,
		DMA_TO_DEVICE);
		} else {
		dmac_clean_range(addr, addr + size);
		}
		}
		}

		static void arm_smmu_init_context_bank(struct arm_smmu_domain *smmu_domain)
		{