On Tue, Jun 25, 2013 at 11:12:15AM +0100, Hiroshi Doyu wrote: > Hi Will,
Hi Hiroshi, > On Mon, 10 Jun 2013 20:34:39 +0200 > Will Deacon <[email protected]> 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. Yes, we could use the same trick there (probably worth moving the logic into a helper function for translating dma_data_direction into IOMMU_* values). There are also iommu_map calls when allocating DMA buffers, but I think 0 is the right thing to pass there (i.e. no permission until pages have been explicitly mapped). Although, to be honest, I don't see why we need to map the buffer at all when we allocate it. Will -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
