On Fri, Jul 29, 2011 at 12:14:25PM +0200, Marek Szyprowski wrote: > > This sounds rather hacky. How about partitioning the address space for > > the device and give the dma-api only a part of it. The other parts can > > be directly mapped using the iommu-api then. > > Well, I'm not convinced that iommu-api should be used by the device drivers > directly. If possible we should rather extend dma-mapping than use such hacks. Building this into dma-api would turn it into an iommu-api. The line between the apis are clear. The iommu-api provides direct mapping of bus-addresses to system-addresses while the dma-api puts a memory manager on-top which deals with bus-address allocation itself. So if you want to map bus-addresses directly the iommu-api is the way to go. This is in no way a hack. Regards, Joerg -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>