From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934035Ab1IOPQM (ORCPT ); Thu, 15 Sep 2011 11:16:12 -0400 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:45402 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756395Ab1IOPQK (ORCPT ); Thu, 15 Sep 2011 11:16:10 -0400 Date: Thu, 15 Sep 2011 11:15:40 -0400 From: Christoph Hellwig To: Jan Kara Cc: Konrad Rzeszutek Wilk , Jan Beulich , Jeremy Fitzhardinge , hch@infradead.org, axboe@kernel.dk, linux-kernel@vger.kernel.org Subject: Re: [PATCH]: xen/blkback: Add support for old BARRIER requests - 'feature-barrier', was "Help with implementing some form of barriers in 3.0 kernels." Message-ID: <20110915151540.GA24348@infradead.org> References: <4E6F50170200007800055CF5@nat28.tlf.novell.com> <20110914085913.GB25628@phenom.oracle.com> <4E708C240200007800055FDF@nat28.tlf.novell.com> <20110914143247.GA17206@phenom.oracle.com> <20110914150102.GA18015@phenom.oracle.com> <4E70EEB302000078000561AE@nat28.tlf.novell.com> <20110915125111.GA18875@phenom.oracle.com> <4E72131B02000078000564AC@nat28.tlf.novell.com> <20110915142125.GB19897@phenom.oracle.com> <20110915151326.GA16195@quack.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110915151326.GA16195@quack.suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Btw, I'm really against exporting any of the low-level request/elevator code interfaces. I have plans for huge changes in that area, and having someone poke into it is just a bad idea. Try to take a look at the barrier era dm implementation of them, which did the draining on the bio layer and copy & paste that.