From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751037AbWGDPZ6 (ORCPT ); Tue, 4 Jul 2006 11:25:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751197AbWGDPZ6 (ORCPT ); Tue, 4 Jul 2006 11:25:58 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:22542 "EHLO spitz.ucw.cz") by vger.kernel.org with ESMTP id S1751037AbWGDPZ5 (ORCPT ); Tue, 4 Jul 2006 11:25:57 -0400 Date: Tue, 4 Jul 2006 15:25:45 +0000 From: Pavel Machek To: Peter Zijlstra Cc: Petr Tesarik , Diego Calleja , linux-kernel@vger.kernel.org Subject: Re: ext4 features Message-ID: <20060704152544.GA4351@ucw.cz> References: <20060701170729.GB8763@irc.pl> <20060701174716.GC24570@cip.informatik.uni-erlangen.de> <20060701181702.GC8763@irc.pl> <20060703202219.GA9707@aitel.hist.no> <20060703205523.GA17122@irc.pl> <1151960503.3108.55.camel@laptopd505.fenrus.org> <44A9904F.7060207@wolfmountaingroup.com> <20060703232547.2d54ab9b.diegocg@gmail.com> <1152004929.3374.13.camel@elijah.suse.cz> <1152012907.23628.20.camel@lappy> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1152012907.23628.20.camel@lappy> User-Agent: Mutt/1.5.9i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > > Add a salvagable file system to ext4, i.e. when a file is deleted, you > > > > just rename it and move it to a directory called DELETED.SAV and recycle > > > > the files as people allocate new ones. Easy to do (internal "mv" of > > > > > > > > > Easily doable in userspace, why bother with kernel programming > > > > Yes and no. A simple mv is better done in userspace, but what I'd > > _really_ appreciate would be a true kernel salvage (similar to the way > > NetWare does things). That means marking the file as deleted in the I have code doing ld_preload tricks to force safe deletion... somewhere. > Wouldn't such a scheme interfere with the block allocator algorithms, > and hence increase the risk of fragmentation? Schemes like this realy > put my hairs on end, > > 1) if you don't want to lose your data, make backups; > 2) if I mean to delete a file, I want it gone proper. Silently keeping > it about is not unix like; Well, mc supports undelete on ext2 for a *long* time. And it works okay... And yes, doing echo > important_file instead of echo >> important file is way too easy with unix shells. Pavel -- Thanks for all the (sleeping) penguins.