From mboxrd@z Thu Jan 1 00:00:00 1970 From: Boaz Harrosh Subject: Re: [PATCH] [14/20] Don't disable direct_io for unchecked_isa_dma in st.c Date: Sun, 16 Mar 2008 14:39:19 +0200 Message-ID: <47DD14F7.4070607@panasas.com> References: <20080307653.720459648@firstfloor.org> <20080307175414.08C981B41AE@basil.firstfloor.org> <20080314135135.GT17940@kernel.dk> <20080314142412.GA30325@infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from bzq-219-195-70.pop.bezeqint.net ([62.219.195.70]:38634 "EHLO bh-buildlin2.bhalevy.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751712AbYCPMkc (ORCPT ); Sun, 16 Mar 2008 08:40:32 -0400 In-Reply-To: <20080314142412.GA30325@infradead.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Christoph Hellwig , Jens Axboe , Mike Christie Cc: Andi Kleen , James.Bottomley@HansenPartnership.com, linux-scsi@vger.kernel.org On Fri, Mar 14 2008 at 16:24 +0200, Christoph Hellwig wrote: > On Fri, Mar 14, 2008 at 02:51:35PM +0100, Jens Axboe wrote: >> Are you sure? Seems to me that st builds its own list with >> get_user_pages() for direct io, where will that get bounced? The block >> layer will only bounce things that are mapped directly, so if st used >> blk_rq_map_kern() and inserted that request in the queue, we could >> proceed with killing that check in st. > > Which shouldn't be all too difficult and would be the right thing to > do. We really need someone to sit down and convert st/osst/sg to use > the proper block layer helpers. > First they do. They all call scsi_execute_async which at the end produces a BIO and then calls blk_execute_nowait(). and all is swell. Second some one did, long a go, and have submitted them rebased more then 3 times. I'd say their time is do long a go. (I mean Mike Christie) Mike, please, do you have these patches on a public git somewhere I want to help push them. Boaz