From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: libata+SGIO: is .dma_boundary respected? Date: Wed, 22 Mar 2006 20:25:18 +0900 Message-ID: <4421341E.80704@gmail.com> References: <441DC397.9040504@rtr.ca> <441DC9CB.7030203@pobox.com> <441DCAC9.5090603@rtr.ca> <441DCF73.2080600@pobox.com> <441DD101.5050202@rtr.ca> <441DD300.9050702@rtr.ca> <441F544A.6080301@pobox.com> <441F8478.50806@rtr.ca> <441F99AC.4000200@pobox.com> <442006BC.8020100@rtr.ca> <20060321184215.GJ4285@suse.de> <442051A0.1050200@rtr.ca> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from pproxy.gmail.com ([64.233.166.176]:12806 "EHLO pproxy.gmail.com") by vger.kernel.org with ESMTP id S1750704AbWCVLZd (ORCPT ); Wed, 22 Mar 2006 06:25:33 -0500 Received: by pproxy.gmail.com with SMTP id m51so101416pye for ; Wed, 22 Mar 2006 03:25:32 -0800 (PST) In-Reply-To: <442051A0.1050200@rtr.ca> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Mark Lord Cc: Jens Axboe , Jeff Garzik , IDE/ATA development list Hello, all. Mark Lord wrote: > Jens Axboe wrote: > .. >> Seems to me that your reasoning is correct. It's a fact that the >> original block mapped sg lists satisfies all requirements of the device >> driver and/or hardware, otherwise would be a bug. The iommu may go nuts >> of course, but logically that new sg list should be choppable into the >> same requirements. > > I just finished going through all of the arch implementations and, > as near as I can tell, they only ever *merge* sg list items, > and never create additional sg entries. > One question though. Do IOMMU's preserve alignment? ie. Do they align 33k block on 64k boundary? I guess they do, just wanna make sure. -- tejun