From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH v3 2/2][BNX2]: Add iSCSI support to BNX2 devices. Date: Tue, 25 Sep 2007 10:39:17 +0200 Message-ID: <46F8C935.8050907@suse.de> References: <20070908084127G.tomof@acm.org> <46E2884B.2070107@garzik.org> <20070908120036.GB8478@infradead.org> <20070909061551G.tomof@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: open-iscsi@googlegroups.com, hch@infradead.org, jeff@garzik.org, davem@davemloft.net, mchristi@redhat.com, netdev@vger.kernel.org, anilgv@broadcom.com, talm@broadcom.com, lusinsky@broadcom.com, uri@broadcom.com, fujita.tomonori@lab.ntt.co.jp To: tomof@acm.org Return-path: Received: from mx2.suse.de ([195.135.220.15]:60910 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756766AbXIYIjW (ORCPT ); Tue, 25 Sep 2007 04:39:22 -0400 In-Reply-To: <20070909061551G.tomof@acm.org> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hi Tomo, =46UJITA Tomonori wrote: > On Sat, 8 Sep 2007 13:00:36 +0100 > Christoph Hellwig wrote: >=20 >> On Sat, Sep 08, 2007 at 07:32:27AM -0400, Jeff Garzik wrote: >>> FUJITA Tomonori wrote: >>>> Yeah, iommu code ignores the lld limitations (the problem is that = the >>>> lld limitations are in request_queue and iommu code can't access t= o >>>> request_queue). There is no way to tell iommu code about the lld >>>> limitations. >>> >>> This fact very much wants fixing. >> >> Absolutely. Unfortunately everyone wastes their time on creating wo= rkarounds >> instead of fixing the underlying problem. >=20 > Any ideas on how to fix this? >=20 > I chatted to Jens and James on this last week. >=20 > - we could just copies the lld limitations to device structure. it's > hacky but device structure already has hacky stuff. >=20 > - we could just link device structure to request_queue structure so > that iommu code can see request_queue structure. >=20 > - we could remove the lld limitations in request_queue strucutre and > have a new strucutre (something like struct io_restrictions). then > somehow we could link the new structure with request_queue and device > strucutres. >=20 I'd prefer the latter. These struct io_restrictions could then be used by dm (which has it's own version right now) to merge queue capabilitie= s. Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: Markus Rex, HRB 16746 (AG N=FCrnberg)