From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751507AbWGMHs5 (ORCPT ); Thu, 13 Jul 2006 03:48:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751508AbWGMHs5 (ORCPT ); Thu, 13 Jul 2006 03:48:57 -0400 Received: from hp3.statik.TU-Cottbus.De ([141.43.120.68]:11725 "EHLO hp3.statik.tu-cottbus.de") by vger.kernel.org with ESMTP id S1751507AbWGMHs4 (ORCPT ); Thu, 13 Jul 2006 03:48:56 -0400 Message-ID: <44B5FA31.9030309@s5r6.in-berlin.de> Date: Thu, 13 Jul 2006 09:45:53 +0200 From: Stefan Richter User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.12) Gecko/20050915 X-Accept-Language: de, en MIME-Version: 1.0 To: ralphc@pathscale.com CC: David Miller , rdreier@cisco.com, rolandd@cisco.com, openib-general@openib.org, linux-kernel@vger.kernel.org Subject: Re: Suggestions for how to remove bus_to_virt() References: <1152746967.4572.263.camel@brick.pathscale.com> <20060712.174013.95062313.davem@davemloft.net> In-Reply-To: <20060712.174013.95062313.davem@davemloft.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org David Miller wrote: > If you need device level DMA mapping semantics, create them for your > device type. This is what USB does, btw. Ralph, two other examples where drivers provide some sort of address lookup are: - drivers/ieee1394/dma.[hc] AFAIK this deals with housekeeping of ringbuffers as used by 1394 controllers for isochronous transmit and receive. Users of this little API are dv1394, video1394, ohci1394. - patch "dc395x: dynamically map scatter-gather for PIO" by Guennadi Liakhovetski, http://kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=cdb8c2a6d848deb9eeefffff42974478fbb51b8c This mapping is not specific to SCSI. The user is a driver which mixes PIO and DMA. I don't know if these have any similarity to your requirements though. (I too need to come up with either a portable replacement of bus_to_virt or with a fundamentally different implementation but haven't started my project yet. This occurrence of bus_to_virt is in drivers/ieee1394/sbp2 but #ifdef'd out by default.) -- Stefan Richter -=====-=-==- -=== -==-- http://arcgraph.de/sr/