Hi Hiroshi, On Thu, Jun 20, 2013 at 06:49:41AM +0100, Hiroshi Doyu wrote: > In Tegra SoC, IOMMU can set some mapping attribute for each page, for > exmaple, READable, and WRITEable. We'd like to use this feature > *newly* for robustness, where read-only pages can be protected from > being overwritten by wrong operation. We have been using IOMMU via DMA > mapping API(ARM). DMA mapping API currently doesn't use "prot" > parameter when calling IOMMU API. So this series tries to pass "struct > dma_attrs *attrs" via "int prot" in IOMMU API. I'm not so sure if this > implementation is right or not because: > > - Casting (struct dma_attrs *) to (int) in DMA API doesn't look nice. > - IOMMU layer needs to cast (int) back to (struct dma_attrs *) again, > which can be considered as violation of layers. > > If you have any implementations/suggestions, it would be really helpful. > > This series isn't applied cleanly but this is posted to request for > comments. > > Hiroshi Doyu (3): > common: DMA-mapping: add DMA_ATTR_READ_ONLY attribute > ARM: dma-mapping: Pass DMA attrs as IOMMU prot > iommu/tegra: smmu: Support read-only mapping These patches don't seem to have made it to the linux-arm-kernel list (either in my inbox or the list archive). Could you try and resend them please? Also: how do they interact with my patch here?: http://lists.infradead.org/pipermail/linux-arm-kernel/2013-June/175124.html Will -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
