From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 7 Jun 2001 17:59:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 7 Jun 2001 17:59:22 -0400 Received: from runyon.cygnus.com ([205.180.230.5]:59786 "EHLO cygnus.com") by vger.kernel.org with ESMTP id ; Thu, 7 Jun 2001 17:59:16 -0400 Date: Thu, 7 Jun 2001 14:59:12 -0700 From: Richard Henderson To: Linus Torvalds Cc: Jens Axboe , Patrick Mochel , Alan Cox , "David S. Miller" , MOLNAR Ingo , Kanoj Sarcar , Kernel Mailing List Subject: Re: [patch] 32-bit dma memory zone Message-ID: <20010607145912.B2286@redhat.com> In-Reply-To: <20010607153119.H1522@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: ; from torvalds@transmeta.com on Thu, Jun 07, 2001 at 02:22:10PM -0700 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 07, 2001 at 02:22:10PM -0700, Linus Torvalds wrote: > For example, what's the difference between ZONE_HIGHMEM and ZONE_NORMAL > on a sane 64-bit architecture (right now I _think_ the 64-bit architectures > actually make ZONE_NORMAL be what we call ZONE_DMA32 on x86, because they > already need to be able to distinguish between memory that can be PCI-DMA'd > to, and memory that needs bounce-buffers. Or maybe it's ZONE_DMA that they > use for the DMA32 stuff?). On most alphas we use only one zone -- ZONE_DMA. The iommu makes it possible to do 32-bit pci to the entire memory space. For those alphas without an iommu, we also set up ZONE_NORMAL. r~