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, 25 Jun 2001 11:05:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 25 Jun 2001 11:04:59 -0400 Received: from babel.spoiled.org ([212.84.234.227]:22204 "HELO babel.spoiled.org") by vger.kernel.org with SMTP id ; Mon, 25 Jun 2001 11:04:49 -0400 Date: 25 Jun 2001 15:04:47 -0000 Message-ID: <20010625150447.17109.qmail@babel.spoiled.org> From: Juri Haberland To: phillips@bonn-fries.net (Daniel Phillips) Cc: linux-kernel@vger.kernel.org Subject: Re: FAT32 superiority over ext2 :-) X-Newsgroups: spoiled.linux.kernel In-Reply-To: <0106250203070J.00430@starship> User-Agent: tin/1.4.4-20000803 ("Vet for the Insane") (UNIX) (OpenBSD/2.9 (i386)) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org In article <0106250203070J.00430@starship> you wrote: > On Monday 25 June 2001 01:49, Albert D. Cahalan wrote: >> Daniel Phillips writes: >> > On Monday 25 June 2001 00:54, Albert D. Cahalan wrote: >> >> By dumb luck (?), FAT32 is compatible with the phase-tree algorithm >> >> as seen in Tux2. This means it offers full data integrity. >> >> Yep, it whips your typical journalling filesystem. Look at what >> >> we have in the superblock (boot sector): >> >> >> >> __u32 fat32_length; /* sectors/FAT */ >> >> __u16 flags; /* bit 8: fat mirroring, low 4: active fat */ >> >> __u8 version[2]; /* major, minor filesystem version */ >> >> __u32 root_cluster; /* first cluster in root directory */ >> >> __u16 info_sector; /* filesystem info sector */ >> >> >> >> All in one atomic write, one can... >> >> >> >> 1. change the active FAT >> >> 2. change the root directory >> >> 3. change the free space count >> >> >> >> That's enough to atomically move from one phase to the next. >> >> You create new directories in the free space, and make FAT >> >> changes to an inactive FAT copy. Then you write the superblock >> >> to atomically transition to the next phase. [--snip--] > When can we expect the patch? Don't! Blasphemy!!! Juri ;-) -- Juri Haberland