Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764411AbXFEN4W (ORCPT ); Tue, 5 Jun 2007 09:56:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1760591AbXFEN4O (ORCPT ); Tue, 5 Jun 2007 09:56:14 -0400 Received: from havoc.gtf.org ([69.61.125.42]:42120 "EHLO havoc.gtf.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760512AbXFEN4O (ORCPT ); Tue, 5 Jun 2007 09:56:14 -0400 Date: Tue, 5 Jun 2007 09:56:08 -0400 From: Jeff Garzik To: Alan Cox Cc: Christoph Hellwig , David Miller , mroos@linux.ee, linux-kernel@vger.kernel.org Subject: Re: libata & no PCI: dma_[un]map_single undefined Message-ID: <20070605135608.GA31565@havoc.gtf.org> References: <20070603.174010.41894721.davem@davemloft.net> <20070604074719.GB15390@infradead.org> <20070604171952.GA3437@dhcp83-182.boston.redhat.com> <20070605122218.410d611b@the-village.bc.nu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070605122218.410d611b@the-village.bc.nu> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1178 Lines: 35 On Tue, Jun 05, 2007 at 12:22:18PM +0100, Alan Cox wrote: > > NAK > > > > We have generic devices and generic DMA mapping. libata already uses > > the generic stuff. Now fix the platform... > > Nice theory but your generic helpers rely on the map functions working > even for generic hardware that doesn't need them, so at the very least > there is some clean up required. Sure there is some clean up needed -- on the arch side. Even !PCI dma_xxx wrappers that do nothing more than return a dma mapping error are a valid platform implementation. Even !HAS_DMA (s/390?) arches should be using the aforementioned return-error wrappers, mimicing the implementation of PCI functions in linux/pci.h for the !PCI case. libata core for DMA mapping is already generic enough such that, #ifdefs are not needed in the code. OTOH..... further work in libata _is_ need for I/O accessors, to isolate those from the core code. Jeff - 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/