From: Ted Ts'o Subject: Re: [PATCH, RFC] Don't do page stablization if !CONFIG_BLKDEV_INTEGRITY Date: Thu, 8 Mar 2012 16:41:48 -0500 Message-ID: <20120308214148.GD11861@thunk.org> References: <4F57F523.3020703@redhat.com> <4F581BF6.8000305@zabbo.net> <20120308155419.GB6777@thunk.org> <20120308180951.GB29510@shiny> <4F59148A.4070001@panasas.com> <20120308212412.GC11861@thunk.org> <20120308213808.GK29510@shiny> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: Chris Mason , Boaz Harrosh , Zach Brown , Eric Sandeen , linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Return-path: Received: from li9-11.members.linode.com ([67.18.176.11]:47691 "EHLO test.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756222Ab2CHVly (ORCPT ); Thu, 8 Mar 2012 16:41:54 -0500 Content-Disposition: inline In-Reply-To: <20120308213808.GK29510@shiny> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Thu, Mar 08, 2012 at 04:38:08PM -0500, Chris Mason wrote: > Btrfs currently does this, and the DIF code is by definition right > before the write. The pages really only get set writeback when they are > being sent in flight, so the waiting being done by the stable pages > patch is file_write or page_mkwrite being polite and waiting for the IO > to finish before changing the page. Right before submission to the bio layer? Or right before the device driver sends the request to the host bus adapter? I was thinking of the latter.... - Ted