On Wed, Apr 06, 2022 at 03:51:50PM +0200, Christoph Hellwig wrote: > On Wed, Apr 06, 2022 at 09:07:30AM -0300, Jason Gunthorpe wrote: > > Didn't see it > > > > I'll move dev_is_dma_coherent to device.h along with > > device_iommu_mapped() and others then > > No. It it is internal for a reason. It also doesn't actually work > outside of the dma core. E.g. for non-swiotlb ARM configs it will > not actually work. Really? It is the only condition that dma_info_to_prot() tests to decide of IOMMU_CACHE is used or not, so you are saying that there is a condition where a device can be attached to an iommu_domain and dev_is_dma_coherent() returns the wrong information? How does dma-iommu.c safely use it then? In any case I still need to do something about the places checking IOMMU_CAP_CACHE_COHERENCY and thinking that means IOMMU_CACHE works. Any idea? Jason