Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758895AbXLSBO7 (ORCPT ); Tue, 18 Dec 2007 20:14:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753721AbXLSBOu (ORCPT ); Tue, 18 Dec 2007 20:14:50 -0500 Received: from filer.fsl.cs.sunysb.edu ([130.245.126.2]:51190 "EHLO filer.fsl.cs.sunysb.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753068AbXLSBOt (ORCPT ); Tue, 18 Dec 2007 20:14:49 -0500 Date: Tue, 18 Dec 2007 20:14:36 -0500 Message-Id: <200712190114.lBJ1Ean2023273@agora.fsl.cs.sunysb.edu> From: Erez Zadok To: Hugh Dickins Cc: Erez Zadok , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/4] unionfs: restructure unionfs_setattr In-reply-to: Your message of "Wed, 19 Dec 2007 00:53:12 GMT." X-MailKey: Erez_Zadok Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1675 Lines: 34 In message , Hugh Dickins writes: > On Tue, 18 Dec 2007, Erez Zadok wrote: > > In message , Hugh Dickins writes: > > > In order to fix unionfs truncation, we need to move the lower notify_change > > > out of the loop in unionfs_setattr. But when I came to do that, I couldn't > > [...] > > > > Hugh, I want to understand how patches 3/4 and 4/4 are related. In patch 3 > > you say "in order to fix truncation" but you mention a truncation problem > > only in patch 4; is there a patch ordering problem, or they're both related > > to the same issue (with 3/4 being a code cleanup, and 4/4 actually fixing > > the problem)? > > I needed to move that notify_change out of the loop, to fix the truncation > problem, but had great difficulty understanding the loop. So, just as you > say, made the code cleanup first in 3/4, then fixed the problem in 4/4. > > But that cleanup does need your review and testing. A quick look at your setattr patches seems very promising. And I've further realized more cleanup is possible: because we call revalidate_chain at the opening to ->setattr, we're guaranteed to have a valid lower dentry, so for example we can remove the else case for "if (lower_dentry)". I'll be testing this and your other patches, plus look into the locking issues you brought up. Thanks, Erez. -- 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/