From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261661AbULBQYK (ORCPT ); Thu, 2 Dec 2004 11:24:10 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261665AbULBQYJ (ORCPT ); Thu, 2 Dec 2004 11:24:09 -0500 Received: from goliat.gorzow.mm.pl ([62.141.232.226]:48285 "EHLO gorzow.mm.pl") by vger.kernel.org with ESMTP id S261661AbULBQYB (ORCPT ); Thu, 2 Dec 2004 11:24:01 -0500 From: Radoslaw Szkodzinski Reply-To: astralstorm@gorzow.mm.pl To: Martin Schlemmer Subject: Re: cdrecord dev=ATA cannont scanbus as non-root [u] Date: Thu, 2 Dec 2004 17:23:48 +0100 User-Agent: KMail/1.7.1 Cc: Jens Axboe , "J.A. Magallon" , Jan Engelhardt , Lista Linux-Kernel References: <1101763996l.13519l.0l@werewolf.able.es> <20041130071638.GC10450@suse.de> <1101935773.11949.86.camel@nosferatu.lan> In-Reply-To: <1101935773.11949.86.camel@nosferatu.lan> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-2" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200412021723.48883.astralstorm@gorzow.mm.pl> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday 01 of December 2004 22:16, Martin Schlemmer [c] wrote: > On Tue, 2004-11-30 at 08:16 +0100, Jens Axboe wrote: > > On Mon, Nov 29 2004, J.A. Magallon wrote: > > > dev=ATAPI uses ide-scsi interface, through /dev/sgX. And: > > > > scsibus: -1 target: -1 lun: -1 > > > > Warning: Using ATA Packet interface. > > > > Warning: The related Linux kernel interface code seems to be > > > > unmaintained. Warning: There is absolutely NO DMA, operations thus > > > > are slow. > > > > > > dev=ATA uses direct IDE burning. Try that as root. In my box, as root: > > > > Oh no, not this again... Please check the facts: the ATAPI method uses > > the SG_IO ioctl, which is direct-to-device. It does _not_ go through > > /dev/sgX, unless you actually give /dev/sgX as the device name. It has > > nothing to do with ide-scsi. Period. > > > > ATA uses CDROM_SEND_PACKET. This has nothing to do with direct IDE > > burning, it's a crippled interface from the CDROM layer that should not > > be used for anything. scsi-linux-ata.c should be ripped from the > > cdrecord sources, or at least cdrecord should _never_ select that > > transport for 2.6 kernels. For 2.4 you are far better off using > > ide-scsi. > > > > > The scan through ATA lasts much less than with ATAPI, and you can burn > > > with dev=ATA:1,0,0 or dev=/dev/burner, which is the new recommended > > > way. > > > > No! ATAPI is the recommended way. > > Ok, so I am a bit confused here. We basically have 3 ways to use > cdrecord on linux-2.6 without ide-scsi: > > 1) cdrecord dev=/dev/hdx > 2) cdrecord dev=ATA > 3) cdrecord dev=ATAPI > > Now, if I run all three and grep for '^Warning', I get: > > ----- > $ cdrecord dev=/dev/cdrw -scanbus 2>&1 | grep '^Warning' > Warning: Open by 'devname' is unintentional and not supported. > $ cdrecord dev=ATA -scanbus 2>&1 | grep '^Warning' > Warning: Using badly designed ATAPI via /dev/hd* interface. > $ cdrecord dev=ATAPI -scanbus 2>&1 | grep '^Warning' > Warning: Using ATA Packet interface. > Warning: The related Linux kernel interface code seems to be unmaintained. > Warning: There is absolutely NO DMA, operations thus are slow. > $ > ----- > > Which means: > > 1) dev=/dev/hdx - Open by 'devname' is unintentional and not supported. > 2) dev=ATA - Using badly designed ATAPI via /dev/hd* interface. > 3) dev=ATAPI - Using ATA Packet interface. > (And some nice things about it not being maintained and > slow) > Well, dev=ATA:nr,nr,nr will not produce any warning and works correctly with full performance. dev=ATAPI:* gives bad performance and as stated above, shouldn't be used. dev=/dev/hdx is just the same as dev=ATA:/dev/hdx, you can of course replace it with correct numbers if you know them or an alias in /etc/defaults/cdrecord.dfl (The path's from Gentoo, may be different elsewhere.)