On Thu, Jul 01, 2010 at 11:17:34PM -0700, Zach Pfeffer wrote: > Andi Kleen wrote: > > Hmm? dma_map_* does not change any CPU mappings. It only sets up > > DMA mapping(s). > > Sure, but I was saying that iommu_map() doesn't just set up the IOMMU > mappings, its sets up both the iommu and kernel buffer mappings. What do you mean by kernel buffer mappings? > > That assumes that all the IOMMUs on the system support the same page table > > format, right? > > Actually no. Since the VCMM abstracts a page-table as a Virtual > Contiguous Region (VCM) a VCM can be associated with any device, > regardless of their individual page table format. The IOMMU-API abstracts a page-table as a domain which can also be associated with any device (behind an iommu). Joerg -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>