From mboxrd@z Thu Jan 1 00:00:00 1970 From: Will Deacon Subject: [PATCH 3/9] ARM: dma-mapping: convert DMA direction into IOMMU protection attributes Date: Mon, 10 Jun 2013 19:34:39 +0100 Message-ID: <1370889285-22799-4-git-send-email-will.deacon@arm.com> References: <1370889285-22799-1-git-send-email-will.deacon@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1370889285-22799-1-git-send-email-will.deacon-5wv7dgnIgG8@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Will Deacon , linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org IOMMU mappings take a prot parameter, identifying the protection bits to enforce on the newly created mapping (READ or WRITE). The ARM dma-mapping framework currently just passes 0 as the prot argument, resulting in faulting mappings. This patch infers the protection attributes based on the direction of the DMA transfer. Cc: Marek Szyprowski Signed-off-by: Will Deacon --- arch/arm/mm/dma-mapping.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 6fb80cf..d119de7 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -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); if (ret < 0) goto fail; -- 1.8.2.2