From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 13 May 2002 00:22:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 13 May 2002 00:22:58 -0400 Received: from daimi.au.dk ([130.225.16.1]:4728 "EHLO daimi.au.dk") by vger.kernel.org with ESMTP id ; Mon, 13 May 2002 00:22:57 -0400 Message-ID: <3CDF3F92.B3C3A18A@daimi.au.dk> Date: Mon, 13 May 2002 06:22:42 +0200 From: Kasper Dupont Organization: daimi.au.dk X-Mailer: Mozilla 4.76 [en] (X11; U; Linux 2.4.9-12smp i686) X-Accept-Language: en MIME-Version: 1.0 To: Alexander Viro CC: Peter Chubb , Elladan , " Jakob =?iso-8859-1?Q?=D8stergaard?=" , Linux-Kernel Subject: Re: [RFC] ext2 and ext3 block reservations can be bypassed In-Reply-To: Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Alexander Viro wrote: > > On Mon, 13 May 2002, Peter Chubb wrote: > > > This is why in SVr4, struct cred is cloned at open time, and passed > > down to each VFS operation. > > That doesn't work for shared mappings over holes. Unfortunately. > Yes, credentials cache a-la 4.4BSD would help in many cases, but > we have no reasonably credentials when kswapd writes a dirty page > on disk. It _can_ cause allocations. And many processes might've > touched that page until it finally got written out - which credentials > would you use? I'd rather have the check done when the page gets dirty in the first place. Refuse the CoW if there is not diskspace to write it back. Right now we can go beyond the diskspace we are allowed to use and we will silently loose data if we go beyond the available diskspace. -- Kasper Dupont -- der bruger for meget tid på usenet. For sending spam use mailto:razor-report@daimi.au.dk