On Mon, 2006-06-05 at 16:34 +0100, Russell King wrote: > What has zero copy (your reply) got to do with faulting pages into > userspace (my message). I'm sorry, I don't understand why you've > brought this up. The zero copy case is the case where we end up with user and kernel mappings simultaneously on the page. The nopage (or fault) case is where we end up with them sequentially. Both cases actually require the same cache treatment, but it's easiest to understand in the zero copy case. James - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html