From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751919Ab2LDC6y (ORCPT ); Mon, 3 Dec 2012 21:58:54 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:24624 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751512Ab2LDC6w (ORCPT ); Mon, 3 Dec 2012 21:58:52 -0500 Message-ID: <50BD66D9.8080408@oracle.com> Date: Mon, 03 Dec 2012 20:58:33 -0600 From: Dave Kleikamp User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Dave Chinner CC: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Zach Brown , "Maxim V. Patlasov" Subject: Re: [PATCH v4 16/31] loop: use aio to perform io on the underlying file References: <1353537671-26284-1-git-send-email-dave.kleikamp@oracle.com> <1353537671-26284-17-git-send-email-dave.kleikamp@oracle.com> <20121122230628.GV2591@dastard> <50BCDA7B.7080000@oracle.com> <20121204025221.GF32450@dastard> In-Reply-To: <20121204025221.GF32450@dastard> X-Enigmail-Version: 1.4.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsinet21.oracle.com [141.146.126.237] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/03/2012 08:52 PM, Dave Chinner wrote: > On Mon, Dec 03, 2012 at 10:59:39AM -0600, Dave Kleikamp wrote: >> On 11/22/2012 05:06 PM, Dave Chinner wrote: >>> And this extra fsync is now not done in the aio path. I.e. the AIO >>> completion path needs to issue the fsync to maintain correct REQ_FUA >>> semantics... >> >> If this is really necessary, I can fix it. > > Absolutely. If we don't implement FUA properly, we'll end up with > corrupted filesystems and/or data loss when kernel crashes or > powerloss occurs. That's not an acceptable outcome, so we need FUA > to be implemented properly. Okay, just wanted to make sure. Thanks, Shaggy