From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S264572AbUEDStG (ORCPT ); Tue, 4 May 2004 14:49:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264573AbUEDStG (ORCPT ); Tue, 4 May 2004 14:49:06 -0400 Received: from [195.23.16.24] ([195.23.16.24]:13215 "EHLO bipbip.comserver-pie.com") by vger.kernel.org with ESMTP id S264572AbUEDStE (ORCPT ); Tue, 4 May 2004 14:49:04 -0400 Message-ID: <4097E4DD.6090904@grupopie.com> Date: Tue, 04 May 2004 19:45:49 +0100 From: Paulo Marques Organization: GrupoPIE User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.4.1) Gecko/20020508 Netscape6/6.2.3 X-Accept-Language: en-us MIME-Version: 1.0 To: Libor Vanek Cc: "Richard B. Johnson" , linux-kernel@vger.kernel.org Subject: Re: Read from file fails References: <20040503000004.GA26707@Loki> <20040503150606.GB6411@Loki> <20040504011957.GA20676@Loki> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-AntiVirus: checked by Vexira MailArmor (version: 2.0.1.16; VAE: 6.25.0.3; VDF: 6.25.0.47; host: bipbip) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Libor Vanek wrote: > Using kernel module: > - user space process wants to change some file which is in "snapshoted" dir > - my module catches this request, holds it, creates copy of original file and allows original request to proceed Did you take a look at LVM snapshots? http://tldp.org/HOWTO/LVM-HOWTO/snapshotintro.html Maybe your problem is already solved... Anyway, you really shouldn't worry about the time it takes to make a context switch when you want to copy a file on modify ;) -- Paulo Marques - www.grupopie.com "In a world without walls and fences who needs windows and gates?"