Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161492AbWJUURa (ORCPT ); Sat, 21 Oct 2006 16:17:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1161490AbWJUURa (ORCPT ); Sat, 21 Oct 2006 16:17:30 -0400 Received: from mail.parknet.jp ([210.171.160.80]:31236 "EHLO parknet.jp") by vger.kernel.org with ESMTP id S1161025AbWJUUR3 (ORCPT ); Sat, 21 Oct 2006 16:17:29 -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> <87lkn9x0ly.fsf@duaron.myhome.or.jp> <20061021173849.GA1999@localhost.localdomain> From: OGAWA Hirofumi Date: Sun, 22 Oct 2006 05:17:22 +0900 In-Reply-To: <20061021173849.GA1999@localhost.localdomain> (Damien Wyart's message of "Sat\, 21 Oct 2006 19\:38\:49 +0200") Message-ID: <87ac3ptodp.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: 1788 Lines: 41 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. > > * OGAWA Hirofumi [2006-10-21 22:24]: >> 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)". > > Reverting the change makes the problem go away. But I do not know if > this is safe wrt the fs-prepare_write-fixes patch. Yes, maybe another patch will be needed. However, I don't know the background of this change. I'll make time and see what happened. -- 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/