On Mon, Jul 12, 2010 at 10:21:05PM -0700, Zach Pfeffer wrote: > Joerg Roedel wrote: > > The DMA-API already does this with the help of IOMMUs if they are > > present. What is the benefit of your approach over that? > > The grist to the DMA-API mill is the opaque scatterlist. Each > scatterlist element brings together a physical address and a bus > address that may be different. The set of scatterlist elements > constitute both the set of physical buffers and the mappings to those > buffers. My approach separates these two things into a struct physmem > which contains the set of physical buffers and a struct reservation > which contains the set of bus addresses (or device addresses). Each > element in the struct physmem may be of various lengths (without > resorting to chaining). A map call maps the one set to the other. Okay, thats a different concept, where is the benefit? 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>