Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992863AbWJUNZK (ORCPT ); Sat, 21 Oct 2006 09:25:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S2992887AbWJUNZK (ORCPT ); Sat, 21 Oct 2006 09:25:10 -0400 Received: from mail.parknet.jp ([210.171.160.80]:23300 "EHLO parknet.jp") by vger.kernel.org with ESMTP id S2992863AbWJUNZH (ORCPT ); Sat, 21 Oct 2006 09:25:07 -0400 X-AuthUser: hirofumi@parknet.jp To: Damien Wyart Cc: linux-kernel , Nick Piggin , Andrew Morton Subject: Re: 2.6.19-rc2-mm2 : empty files on vfat file system References: <20061021104454.GA1996@localhost.localdomain> From: OGAWA Hirofumi Date: Sat, 21 Oct 2006 22:24:57 +0900 In-Reply-To: <20061021104454.GA1996@localhost.localdomain> (Damien Wyart's message of "Sat\, 21 Oct 2006 12\:44\:54 +0200") Message-ID: <87lkn9x0ly.fsf@duaron.myhome.or.jp> User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1702 Lines: 39 Damien Wyart writes: > I have noticed something strange (and bad :) since using 2.6.19-rc2-mm2 > (the problem is NOT present on 2.6.19-rc2-mm1 ; do not know for > mainline, I have not been able to test yet, but I think there have not > been recent changes in this area) : writing a file to a vfat > fs (fat 32) writes it, but with size 0 and no content. All this is > silent : no error message, nothing in the logs. After several attempts, > I checked the fs with fsck.vfat and it reported errors about some of the > files and told it was truncating them to size 0 (but their displayed > size was already 0, btw). diff -puN fs/fat/inode.c~fs-prepare_write-fixes fs/fat/inode.c --- a/fs/fat/inode.c~fs-prepare_write-fixes +++ a/fs/fat/inode.c @@ -150,7 +150,11 @@ static int fat_commit_write(struct file unsigned from, unsigned to) { struct inode *inode = page->mapping->host; - int err = generic_commit_write(file, page, from, to); + int err; + if (to - from > 0) + return 0; + + err = generic_commit_write(file, page, from, to); if (!err && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) { inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC; MSDOS_I(inode)->i_attrs |= ATTR_ARCH; This change does't update ->i_size. Could you just delete, and test it? Anyway, this seems wrong even if it's "if ((to - from) == 0)". The zero range is valid for cont_prepare_write()... -- OGAWA Hirofumi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/