Merge "arm: mm: call __iommu_map_sg for unaligned buffers" (5fb0ec2b) · Commits · e / devices / android_kernel_fairphone_FP3

arch/arm/mm/dma-mapping.c

+34 −3

Original line number	Diff line number	Diff line
		@@ -1862,7 +1862,7 @@ static int __map_sg_chunk(struct device dev, struct scatterlist sg,
		int ret = 0;
		unsigned int count;
		struct scatterlist *s;
		int prot;
		int prot = 0;

		size = PAGE_ALIGN(size);
		*handle = DMA_ERROR_CODE;
		@@ -1871,6 +1871,11 @@ static int __map_sg_chunk(struct device dev, struct scatterlist sg,
		if (iova == DMA_ERROR_CODE)
		return -ENOMEM;

		/*
		* Check for coherency.
		*/
		prot \|= is_coherent ? IOMMU_CACHE : 0;

		for (count = 0, s = sg; count < (size >> PAGE_SHIFT); s = sg_next(s)) {
		phys_addr_t phys = page_to_phys(sg_page(s));
		unsigned int len = PAGE_ALIGN(s->offset + s->length);
		@@ -1878,7 +1883,7 @@ static int __map_sg_chunk(struct device dev, struct scatterlist sg,
		if (!is_coherent && (attrs & DMA_ATTR_SKIP_CPU_SYNC) == 0)
		__dma_page_cpu_to_dev(sg_page(s), s->offset, s->length, dir);

		prot = __dma_direction_to_prot(dir);
		prot \|= __dma_direction_to_prot(dir);

		ret = iommu_map(mapping->domain, iova, phys, len, prot);
		if (ret < 0)
		@@ -1982,9 +1987,35 @@ int arm_iommu_map_sg(struct device dev, struct scatterlist sg,
		dma_addr_t iova;
		bool coherent;
		int prot = __dma_direction_to_prot(dir);
		int upstream_hint = 0;
		/*
		* This is used to check if there are any unaligned offset/size
		* given in the scatter list.
		*/
		bool unaligned_offset_size = false;

		for_each_sg(sg, s, nents, i)
		for_each_sg(sg, s, nents, i) {
		total_length += s->length;
		if ((s->offset & ~PAGE_MASK) \|\| (s->length & ~PAGE_MASK)) {
		unaligned_offset_size = true;
		break;
		}
		}

		/*
		* Check for the upstream domain attribute just to catch
		* any abusive clients who expects the unaligned offset/size
		* support with out setting this attribute.
		* NOTE: on future kernels, we may not have this domain
		* attribute set where the check then will be based on just
		* offset/size.
		*/
		iommu_domain_get_attr(mapping->domain,
		DOMAIN_ATTR_UPSTREAM_IOVA_ALLOCATOR,
		&upstream_hint);
		if (upstream_hint && unaligned_offset_size)
		return __iommu_map_sg(dev, sg, nents, dir, attrs,
		is_dma_coherent(dev, attrs, false));

		iova = __alloc_iova(mapping, total_length);
		if (iova == DMA_ERROR_CODE)