Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753867AbZIQUSc (ORCPT ); Thu, 17 Sep 2009 16:18:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752428AbZIQUSc (ORCPT ); Thu, 17 Sep 2009 16:18:32 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:38804 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751923AbZIQUSb (ORCPT ); Thu, 17 Sep 2009 16:18:31 -0400 Date: Thu, 17 Sep 2009 13:17:55 -0700 (PDT) From: Linus Torvalds X-X-Sender: torvalds@localhost.localdomain To: Roland Dreier cc: Joel Becker , Mark Fasheh , Andrew Morton , Linux Kernel Mailing List , ocfs2-devel@oss.oracle.com Subject: Re: [GIT PULL] ocfs2 changes for 2.6.32 In-Reply-To: Message-ID: References: <20090914221434.GA4507@mail.oracle.com> <20090915000417.GC4507@mail.oracle.com> <20090915005417.GD4507@mail.oracle.com> <20090915040601.GE4507@mail.oracle.com> <20090915214530.GA11060@mail.oracle.com> <20090916044047.GA30453@mail.oracle.com> User-Agent: Alpine 2.01 (LFD 1184 2008-12-16) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 941 Lines: 25 On Thu, 17 Sep 2009, Roland Dreier wrote: > > I guess one bit of semantics to figure out is what happens if copyfile() > does the async case but then copyfile_ctrl() returns an error halfway > through... is the state of the dest file just undefined? I think that's the one that most filesystems would prefer. Maybe the file is there, it's just that it's only half copied because the filesystem filled up. Making filesystems give atomicity guarantees would be hard for the async case. Of course, if the filesystem can do the copy entirely atomically (ie by just incrementing a refcount), then it can give atomicity guarantees, but then you'd never see the async case either. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/