From: Chris Wedgwood Subject: Re: [PATCH 0/5] fallocate system call Date: Sun, 29 Apr 2007 22:25:59 -0700 Message-ID: <20070430052559.GA13145@tuatara.stupidest.org> References: <20070329115126.GB7374@amitarora.in.ibm.com> <20070329101010.7a2b8783.akpm@linux-foundation.org> <20070330071417.GI355@devserv.devel.redhat.com> <20070417125514.GA7574@amitarora.in.ibm.com> <20070418130600.GW5967@schatzie.adilger.int> <20070420135146.GA21352@amitarora.in.ibm.com> <20070420145918.GY355@devserv.devel.redhat.com> <20070424121632.GA10136@amitarora.in.ibm.com> <20070426175056.GA25321@amitarora.in.ibm.com> <20070430004702.GM32602149@melbourne.sgi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "Amit K. Arora" , torvalds@osdl.org, akpm@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, xfs@oss.sgi.com, suparna@in.ibm.com, cmm@us.ibm.com To: David Chinner Return-path: Received: from smtp102.sbc.mail.mud.yahoo.com ([68.142.198.201]:24934 "HELO smtp102.sbc.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1423020AbXD3F0E (ORCPT ); Mon, 30 Apr 2007 01:26:04 -0400 Content-Disposition: inline In-Reply-To: <20070430004702.GM32602149@melbourne.sgi.com> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Mon, Apr 30, 2007 at 10:47:02AM +1000, David Chinner wrote: > For FA_ALLOCATE, it's supposed to change the file size if we > allocate past EOF, right? I would argue no. Use truncate for that. > For FA_DEALLOCATE, does it change the filesize at all? Same as above. > Or does > it just punch a hole in the file? Yes. > FWIW, we definitely need a FA_PREALLOCATE mode (FA_ALLOCATE but does > not change file size) so we can preallocate beyond EOF for apps > which use O_APPEND (i.e. changing file size would cause problems for > them). FA_ALLOCATE should be able to allocate past-EOF I would argue.