Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757677AbcCUSW0 (ORCPT ); Mon, 21 Mar 2016 14:22:26 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:44425 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756223AbcCUSWY (ORCPT ); Mon, 21 Mar 2016 14:22:24 -0400 To: Christoph Hellwig Cc: "Darrick J. Wong" , axboe@kernel.dk, torvalds@linux-foundation.org, bfields@fieldses.org, tytso@mit.edu, martin.petersen@oracle.com, linux-api@vger.kernel.org, david@fromorbit.com, linux-kernel@vger.kernel.org, shane.seymour@hpe.com, linux-fsdevel@vger.kernel.org, jlayton@poochiereds.net, akpm@linux-foundation.org Subject: Re: [PATCH 3/3] block: implement (some of) fallocate for block devices From: "Martin K. Petersen" Organization: Oracle Corporation References: <20160315194221.30093.70506.stgit@birch.djwong.org> <20160315194244.30093.6483.stgit@birch.djwong.org> <20160321153827.GA27230@infradead.org> <20160321175235.GA5812@birch.djwong.org> <20160321181726.GA10892@infradead.org> Date: Mon, 21 Mar 2016 14:21:39 -0400 In-Reply-To: <20160321181726.GA10892@infradead.org> (Christoph Hellwig's message of "Mon, 21 Mar 2016 11:17:26 -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: userv0021.oracle.com [156.151.31.71] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 792 Lines: 19 >>>>> "Christoph" == Christoph Hellwig writes: Christoph> On Mon, Mar 21, 2016 at 10:52:35AM -0700, Darrick J. Wong wrote: >> > I don't really understand the comment. But I think you'd be much >> >> I don't know of a block device primitive that corresponds to the >> "default" mode of fallocate, as documented in the manpage (i.e. mode >> == 0). I agree that the whole thing could be simplified in the >> manner you point out below. Christoph> SCSI allows 'anchoring' blocks, which is pretty similar to a Christoph> normal fallocate, but we don't support anchoring blocks in Christoph> Linux yet. Chicken and egg problem. I actually did tinker with this for a different project a while back and can easily revive it. -- Martin K. Petersen Oracle Linux Engineering