> @@ -693,7 +694,19 @@ dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, > unsigned long offset, size_t size, int prot) > { > return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot, > - iommu_get_dma_domain(dev)); > + iommu_get_dma_domain(dev), dma_get_mask(dev)); > +} > + > +dma_addr_t iommu_dma_map_page_coherent(struct device *dev, struct page *page, > + unsigned long offset, size_t size, int prot) > +{ Note that my tree pointed to above removes the iommu_dma_map_page wrapper. I think for the coherent mappign we should also just call __iommu_dma_map directly and not introduce another wrapper. > + dma_addr_t dma_mask = dev->coherent_dma_mask; > + > + if (!dma_mask) > + dma_mask = dma_get_mask(dev); > + > + return __iommu_dma_map(dev, page_to_phys(page) + offset, size, prot, > + iommu_get_dma_domain(dev), dma_mask); > } In the DMA API there is no fallback when the coherent_dma_mask is not set. While various bits of legacy code do that we should not copy it to new code.