On Tue, Feb 3, 2015 at 9:37 AM, Russell King - ARM Linux <linux@xxxxxxxxxxxxxxxx> wrote: > 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. Tell the exporter to stop using carveouts, and give me proper memory instead.. ;-) Well, at least on these SoC's, I think the only valid use for carveout memory is the bootloader splashscreen. And I was planning on just hanging on to that for myself for fbdev scanout buffer or other internal (non shared) usage.. BR, -R > -- > 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>