From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762893AbYGBKTe (ORCPT ); Wed, 2 Jul 2008 06:19:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751767AbYGBKTX (ORCPT ); Wed, 2 Jul 2008 06:19:23 -0400 Received: from bu3sch.de ([62.75.166.246]:41889 "EHLO vs166246.vserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751660AbYGBKTX (ORCPT ); Wed, 2 Jul 2008 06:19:23 -0400 From: Michael Buesch To: Andrew Morton Subject: Re: [PATCH v2 -mm 1/2] add the device argument to dma_mapping_error Date: Wed, 2 Jul 2008 12:18:40 +0200 User-Agent: KMail/1.9.6 (enterprise 0.20070907.709405) Cc: FUJITA Tomonori , linux-kernel@vger.kernel.org, amit.shah@qumranet.com, muli@il.ibm.com, alexisb@us.ibm.com, andi@firstfloor.org, kvm-devel@lists.sourceforge.net, avi@qumranet.com References: <1211178689-3507-1-git-send-email-fujita.tomonori@lab.ntt.co.jp> <1211178689-3507-2-git-send-email-fujita.tomonori@lab.ntt.co.jp> <20080702030723.dabf7546.akpm@linux-foundation.org> In-Reply-To: <20080702030723.dabf7546.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200807021218.41153.mb@bu3sch.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 02 July 2008 12:07:23 Andrew Morton wrote: > On Mon, 19 May 2008 15:31:28 +0900 FUJITA Tomonori wrote: > > > dma_mapping_error doesn't take a pointer to the device unlike other > > DMA operations. So we can't have dma_mapping_ops per device. > > > > Note that POWER already has dma_mapping_ops per device but all the > > POWER IOMMUs use the same dma_mapping_error function. x86 IOMMUs use > > different dma_mapping_error functions. So dma_mapping_error needs the > > device argument. > > This patch continues to turn my hair grey. > > I'm currently staring at this, in include/linux/ssb/ssb.h: > > static inline int ssb_dma_mapping_error(struct ssb_device *dev, dma_addr_t addr) > { > switch (dev->bus->bustype) { > case SSB_BUSTYPE_PCI: > return pci_dma_mapping_error(dev->dev, addr); > case SSB_BUSTYPE_SSB: > return dma_mapping_error(dev->dev, addr); > default: > __ssb_dma_not_implemented(dev); > } > return -ENOSYS; > } > > How do I go from an ssb_device* to a pci_dev*? > > Dunno. I think I'll cheat and do: > > static inline int ssb_dma_mapping_error(struct ssb_device *dev, dma_addr_t addr) > { > switch (dev->bus->bustype) { > case SSB_BUSTYPE_PCI: > return dma_mapping_error(dev->dev, addr); The statement above is wrong. The PCI-specific dma-mapping-error function must be used here. (I hope such a thing exists. Otherwise the API is broken). So return pci_mapping_error(dev->bus->host_pci, addr); > case SSB_BUSTYPE_SSB: > return dma_mapping_error(dev->dev, addr); > default: > __ssb_dma_not_implemented(dev); > } > return -ENOSYS; > } -- Greetings Michael.