From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S268260AbTGLSte (ORCPT ); Sat, 12 Jul 2003 14:49:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268281AbTGLStd (ORCPT ); Sat, 12 Jul 2003 14:49:33 -0400 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:2188 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S268260AbTGLStc (ORCPT ); Sat, 12 Jul 2003 14:49:32 -0400 Message-ID: <3F105B9A.7070803@pobox.com> Date: Sat, 12 Jul 2003 15:03:54 -0400 From: Jeff Garzik Organization: none User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.2.1) Gecko/20021213 Debian/1.2.1-2.bunk X-Accept-Language: en MIME-Version: 1.0 To: Jamie Lokier CC: Andrew Morton , davej@codemonkey.org.uk, linux-kernel@vger.kernel.org Subject: Re: 2.5 'what to expect' References: <20030711140219.GB16433@suse.de> <20030712152406.GA9521@mail.jlokier.co.uk> <3F103018.6020008@pobox.com> <20030712112722.55f80b60.akpm@osdl.org> <20030712183929.GA10450@mail.jlokier.co.uk> In-Reply-To: <20030712183929.GA10450@mail.jlokier.co.uk> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Jamie Lokier wrote: > Andrew Morton wrote: > >>>One problem is O_DIRECT should return an error on open(2) or fcntl(2), >>> not write(2). >> >>That is the 2.5 behaviour. > > > What do you mean? > > The problem with db4 is that operations on O_DIRECT handles now return > EINVAL if the address isn't suitable aligned, and db4 is not expecting > that - it aborts. That was true for 2.5.74, at least. These are separate db4+kernel problems. The first is that there needs to be a reliable way to know if O_DIRECT writes are going to succeed or not. The 2.4 kernel fails on write(2) but not open(2) or fcntl(2). The second is that db4 doesn't appear to know about the alignment requirement. Jeff