On Tue, Oct 06, 2020 at 08:23:06AM +0100, Christoph Hellwig wrote: > If people want to use the "raw" IOMMU API with not cache coherent > devices we'll need a cache maintainance API that goes along with it. > It could either be formally part of the IOMMU API or be separate. The IOMMU-API does not care about the caching effects of DMA, is manages IO address spaces for devices. I also don't know how this would be going to be implemented, the IOMMU-API does not have the concept of handles for mapped ranges and does not care about CPU virtual addresses (which are needed for cache flushes) of the memory it maps into IO page-tables. So I think a cache management API should be separate from the IOMMU-API. Regards, Joerg
