From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030824AbXDVUHI (ORCPT ); Sun, 22 Apr 2007 16:07:08 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030869AbXDVUHI (ORCPT ); Sun, 22 Apr 2007 16:07:08 -0400 Received: from smtp01.cdmon.com ([86.109.99.230]:53349 "EHLO smtp01.cdmon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030824AbXDVUHG (ORCPT ); Sun, 22 Apr 2007 16:07:06 -0400 Date: Sun, 22 Apr 2007 22:08:39 +0200 From: DervishD To: OGAWA Hirofumi Cc: Andrew Morton , Juergen Beisert , linux-kernel@vger.kernel.org Subject: Re: Wrong free clusters count on FAT32 Message-ID: <20070422200839.GC12748@DervishD> Mail-Followup-To: OGAWA Hirofumi , Andrew Morton , Juergen Beisert , linux-kernel@vger.kernel.org References: <20070419085750.GA2833@DervishD> <200704191352.06456.juergen127@kreuzholzen.de> <20070419141942.GF8287@DervishD> <87d51xtkmp.fsf@duaron.myhome.or.jp> <20070421201841.85717088.akpm@linux-foundation.org> <87wt05vxu7.fsf@duaron.myhome.or.jp> <20070422112658.GB5786@DervishD> <87mz10tyi1.fsf@duaron.myhome.or.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87mz10tyi1.fsf@duaron.myhome.or.jp> User-Agent: Mutt/1.4.2.2i Organization: DervishD Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi Ogawa :) * OGAWA Hirofumi dixit: > DervishD writes: > > The problem is that if a program writes a file onto the filesystem > > without using statfs first to check for free space, the free_clusters > > entry won't have the real value and the driver may report "disk full" (I > > haven't read the code for the vfat driver, sorry, so I'm not sure about > > this) when really there are plenty of clusters to write the new file. > > No need to worry about it. If we ignored the ->free_clusters in > FSINFO, the fat drivers counts the current free clusters by scaning > FAT entries if needed. Cool! :) > > Probably it's stupid to update the free clusters count at mount time > > (sorry if so...) but it looks like a good idea to me. And of course, I > > don't mean to update the value _on disk_, but the kernel's idea of free > > clusters (so even FAT filesystems mounted R/O will report correct > > values). > > It would add the limitation to following simple usage, > > # mount -t vfat /dev/sda1 /mnt > # cp -a * /mnt > # umount > > if /dev/sda1 was the large and slow device, "mount" will need several > minutes to counts free clusters. I think the user will be hard to > accept the several minutes at "mount". I can carry some tests, but if Windows does that tasks lightning fast, Linux surely does it faster ;) I don't think, anyway, that having a huge USB disk is a common practice when using "modest" machines. If you want, I can perform a couple of tests. I have a 80GB disk that I can connect using an USB adapter and my machine is AMD Athlon XP 1900+ with 1GB of RAM, which looks pretty slow nowadays O:) Raúl Núñez de Arenas Coronado -- Linux Registered User 88736 | http://www.dervishd.net It's my PC and I'll cry if I want to... RAmen!