On Mon, Oct 14, 2019 at 11:29:24AM +0100, Robin Murphy wrote: >> However, I would like to see the commit message (and maybe the inline >> comments) expanded a bit on what the distinction here is about. Some >> of the text from the next patch would be suitable, about DMA addresses >> usually being in a different address space but not in the case of >> bounce buffering. > > Right, this needs a much tighter definition. "DMA address happens to be a > valid physical address" is true of various IOMMU setups too, but I can't > believe it's meaningful in such cases. > > If what you actually want is "DMA is direct or SWIOTLB" - i.e. "DMA address > is physical address of DMA data (not necessarily the original buffer)" - > wouldn't dma_is_direct() suffice? It would. But drivers have absolutely no business knowing any of this. _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization