From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S266003AbUBCNf4 (ORCPT ); Tue, 3 Feb 2004 08:35:56 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S266004AbUBCNf4 (ORCPT ); Tue, 3 Feb 2004 08:35:56 -0500 Received: from users.linvision.com ([62.58.92.114]:42681 "HELO bitwizard.nl") by vger.kernel.org with SMTP id S266003AbUBCNfx (ORCPT ); Tue, 3 Feb 2004 08:35:53 -0500 Date: Tue, 3 Feb 2004 14:35:51 +0100 From: Erik Mouw To: "P. Christeas" Cc: lkml , viro@math.psu.edu Subject: Re: Q: large files in iso9660 ? Message-ID: <20040203133551.GA11957@bitwizard.nl> References: <200402020024.31785.p_christ@hol.gr> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200402020024.31785.p_christ@hol.gr> User-Agent: Mutt/1.3.28i Organization: Harddisk-recovery.com Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 02, 2004 at 12:24:31AM +0200, P. Christeas wrote: > I've tried to create a disk (DVD) which contains a single 3.8GB file. The > creation (mkisofs) worked and the disk's TOC reads 3.8GB. No, it didn't. Last time I tried mkisofs warned about files being larger than 2GB. Feel free to ignore the warnings, though. > However, the > filesystem reads as if one ~9MB file only exists. > I guess large files in isofs may be out of spec. > > Q: What's the file size limit in iso9660? About 2GB. > Q: Is there any chance the negative number (although out of spec) may be > correctly interpreted (mount option) ? The kernel (2.6 and 2.4) has the following code in isofs_read_inode(): /* * The ISO-9660 filesystem only stores 32 bits for file size. * mkisofs handles files up to 2GB-2 = 2147483646 = 0x7FFFFFFE bytes * in size. This is according to the large file summit paper from 1996. * WARNING: ISO-9660 filesystems > 1 GB and even > 2 GB are fully * legal. Do not prevent to use DVD's schilling@fokus.gmd.de */ if ((inode->i_size < 0 || inode->i_size > 0x7FFFFFFE) && sbi->s_cruft == 'n') { printk(KERN_WARNING "Warning: defective CD-ROM. " "Enabling \"cruft\" mount option.\n"); sbi->s_cruft = 'y'; } IOW: your kernel should have warned you about the defective CDROM and truncated filesizes to 16MB (which is what the "cruft" mount option does). Erik -- +-- Erik Mouw -- www.harddisk-recovery.com -- +31 70 370 12 90 -- | Lab address: Delftechpark 26, 2628 XH, Delft, The Netherlands