From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757869AbYIDI3j (ORCPT ); Thu, 4 Sep 2008 04:29:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758194AbYIDI2O (ORCPT ); Thu, 4 Sep 2008 04:28:14 -0400 Received: from one.firstfloor.org ([213.235.205.2]:55172 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757852AbYIDI2N (ORCPT ); Thu, 4 Sep 2008 04:28:13 -0400 Date: Thu, 4 Sep 2008 10:31:24 +0200 From: Andi Kleen To: FUJITA Tomonori Cc: andi@firstfloor.org, joerg.roedel@amd.com, mingo@redhat.com, tglx@linutronix.de, hpa@zytor.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, kamezawa.hiroyu@jp.fujitsu.com, tony.luck@intel.com Subject: Re: [PATCH] swiotlb: fix dma_alloc_coherent allocation failures with swiotlb Message-ID: <20080904083124.GA18288@one.firstfloor.org> References: <20080904074441.GY18288@one.firstfloor.org> <20080904165852I.fujita.tomonori@lab.ntt.co.jp> <20080904080528.GZ18288@one.firstfloor.org> <20080904171903M.fujita.tomonori@lab.ntt.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080904171903M.fujita.tomonori@lab.ntt.co.jp> User-Agent: Mutt/1.4.2.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Even if it's tree, only each IOMMU knows what's the best. That's the > point of these changes to remove the tricks in arch/x86/pci-dma.c and > let IOMMUs do what they want. Duplicating all the code. Sounds great. > > Also there's usually the problem that not all busses are translated, > > e.g. Calgary used to do that so for e.g. dev == NULL allocations you had > > to use these fallback algorithms anyways. > > dev == NULL isn't a minor thing. It's just using the fallback > device. You still have to handle it fully. -Andi