From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751982AbcFJCFz (ORCPT ); Thu, 9 Jun 2016 22:05:55 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:40102 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750772AbcFJCFy (ORCPT ); Thu, 9 Jun 2016 22:05:54 -0400 To: Christoph Hellwig Cc: "Martin K. Petersen" , Mike Snitzer , Shaohua Li , linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, sitsofe@yahoo.com, axboe@fb.com, Kernel-team@fb.com Subject: Re: block: correctly fallback for zeroout From: "Martin K. Petersen" Organization: Oracle Corporation References: <20160526180813.GA49039@shli-mbp.local> <20160529064728.GA14383@infradead.org> <20160603035415.GA8236@redhat.com> <20160607063842.GA21032@infradead.org> Date: Thu, 09 Jun 2016 22:05:21 -0400 In-Reply-To: <20160607063842.GA21032@infradead.org> (Christoph Hellwig's message of "Mon, 6 Jun 2016 23:38:42 -0700") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org >>>>> "Christoph" == Christoph Hellwig writes: >> Userland apps rely on EOPNOTSUPP, we can't break that. Christoph> Rely on what exactly? Current we return EOPNOTSUPP if the Christoph> device doesn't claim to support discards, but it returns 0 if Christoph> the device first claims to support it but then fails the I/O. Hopefully we can clean up this when/if we go the fallocate() route. -- Martin K. Petersen Oracle Linux Engineering