On Friday 07 August 2009 00:25:43 Russell King - ARM Linux wrote: > > As far as userspace DMA coherency, the only way you could do it with > current kernel APIs is by using get_user_pages(), creating a scatterlist > from those, and then passing it to dma_map_sg(). While the device has > ownership of the SG, userspace must _not_ touch the buffer until after > DMA has completed. If the buffers are going to be reused again and again, would it be possible to mark the pages returned by get_user_pages() as non-cacheable instead ? Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html