[PATCH 3/9] ARM: dma-mapping: convert DMA direction into IOMMU protection attributes

[Hiroshi Doyu]

Hi Will,

On Mon, 10 Jun 2013 20:34:39 +0200
Will Deacon <will.deacon at arm.com> wrote:
...
> @@ -1636,13 +1636,27 @@ static dma_addr_t arm_coherent_iommu_map_page(struct device *dev, struct page *p
>  {
>  	struct dma_iommu_mapping *mapping = dev->archdata.mapping;
>  	dma_addr_t dma_addr;
> -	int ret, len = PAGE_ALIGN(size + offset);
> +	int ret, prot, len = PAGE_ALIGN(size + offset);
>  
>  	dma_addr = __alloc_iova(mapping, len);
>  	if (dma_addr == DMA_ERROR_CODE)
>  		return dma_addr;
>  
> -	ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, 0);
> +	switch (dir) {
> +	case DMA_BIDIRECTIONAL:
> +		prot = IOMMU_READ | IOMMU_WRITE;
> +		break;
> +	case DMA_TO_DEVICE:
> +		prot = IOMMU_READ;
> +		break;
> +	case DMA_FROM_DEVICE:
> +		prot = IOMMU_WRITE;
> +		break;
> +	default:
> +		prot = 0;
> +	}
> +
> +	ret = iommu_map(mapping->domain, dma_addr, page_to_phys(page), len, prot);

Do we need similar changes for map_sg case as well? They still passes '0' as prot.