Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754036AbYHLQtZ (ORCPT ); Tue, 12 Aug 2008 12:49:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752170AbYHLQtR (ORCPT ); Tue, 12 Aug 2008 12:49:17 -0400 Received: from 8bytes.org ([88.198.83.132]:46723 "EHLO 8bytes.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751861AbYHLQtR (ORCPT ); Tue, 12 Aug 2008 12:49:17 -0400 Date: Tue, 12 Aug 2008 18:49:14 +0200 From: Joerg Roedel To: Muli Ben-Yehuda Cc: Joerg Roedel , mingo@redhat.com, tglx@linutronix.de, hpa@zytor.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, andi@firstfloor.org Subject: Re: [PATCH 0/7] x86 dma_*_coherent rework patchset Message-ID: <20080812164914.GC4342@8bytes.org> References: <1218554657-16070-1-git-send-email-joerg.roedel@amd.com> <20080812160658.GH30426@il.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080812160658.GH30426@il.ibm.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1542 Lines: 34 On Tue, Aug 12, 2008 at 07:06:58PM +0300, Muli Ben-Yehuda wrote: > [added Andi to CC] > > On Tue, Aug 12, 2008 at 05:24:10PM +0200, Joerg Roedel wrote: > > Hi, > > > > this patchset reworks the dma_*_coherent functions in the DMA layer > > for the x86 architecture. The patch series extends the existing DMA > > backends with missing *coherent callbacks and simplifies the generic > > function to basically only call the registered backend. This allows > > future optimizations in hardware specific IOMMU implementations. > > The code ist tested on AMD64 with AMD IOMMU and GART as well as on > > my old 486 box. It is not yet tested on a Calgary IOMMU system. > > Now it is---appears to work fine on a Calgary system. > > In general the patchset looks good and is definitely a step in the > right direction. I am a bit concerned about the contortions that the > generic dma_alloc_coherent went through before calling the ops > version---have you verified they are no longer needed? Most of the logic in the old dma_alloc_coherent function is moved to the specific IOMMU implementations now. The old function tried to handle all cases, hardware IOMMU, GART and NOMMU in one function which made it a bit hard to read. This logic is split up and moved to the specific DMA backends now. Joerg -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/