On Tue, Feb 03, 2015 at 09:04:03AM -0500, Rob Clark wrote: > Since I'm stuck w/ an iommu, instead of built in mmu, my plan was to > drop use of dma-mapping entirely (incl the current call to dma_map_sg, > which I just need until we can use drm_cflush on arm), and > attach/detach iommu domains directly to implement context switches. > At that point, dma_addr_t really has no sensible meaning for me. So how do you intend to import from a subsystem which only gives you the dma_addr_t? If you aren't passing system memory, you have no struct page. You can't fake up a struct page. What this means is that struct scatterlist can't represent it any other way. -- FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up according to speedtest.net. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>