2004-03-04 21:12:18

by Olaf Frączyk

[permalink] [raw]
Subject: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

Hi,
I switched to 2.6.3 from 2.4.x serie.
When I mount DVD-RAM it is mounted read-only:

[root@venus olaf]# mount /dev/dvdram /mnt/dvdram
mount: block device /dev/dvdram is write-protected, mounting read-only
[root@venus olaf]#

In 2.4 it is mounted correctly as read-write.

Drive: Panasonic LF-201, reported in Linux as:
MATSHITA DVD-RAM LF-D200 A120

SCSI controller: Adaptec 2940U2W

Please CC me.

Regards,

Olaf Fraczyk


2004-03-05 08:23:54

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> Hi,
> I switched to 2.6.3 from 2.4.x serie.
> When I mount DVD-RAM it is mounted read-only:
>
> [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> mount: block device /dev/dvdram is write-protected, mounting read-only
> [root@venus olaf]#
>
> In 2.4 it is mounted correctly as read-write.
>
> Drive: Panasonic LF-201, reported in Linux as:
> MATSHITA DVD-RAM LF-D200 A120
>
> SCSI controller: Adaptec 2940U2W

What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
messages in dmesg when the rw mount fails?

--
Jens Axboe

2004-03-05 11:42:25

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > Hi,
> > I switched to 2.6.3 from 2.4.x serie.
> > When I mount DVD-RAM it is mounted read-only:
> >
> > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > mount: block device /dev/dvdram is write-protected, mounting read-only
> > [root@venus olaf]#
> >
> > In 2.4 it is mounted correctly as read-write.
> >
> > Drive: Panasonic LF-201, reported in Linux as:
> > MATSHITA DVD-RAM LF-D200 A120
> >
> > SCSI controller: Adaptec 2940U2W
>
> What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> messages in dmesg when the rw mount fails?

I get nothing in /var/log/dmesg and in /var/log/messages
In /proc/sys/dev/cdrom/info I get:
[olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
CD-ROM information, Id: cdrom.c 3.20 2003/12/17

drive name: sr1 sr0 hdc
drive speed: 0 16 44
drive # of slots: 1 1 1
Can close tray: 1 1 1
Can open tray: 1 1 1
Can lock tray: 1 1 1
Can change speed: 1 1 1
Can select disk: 0 0 0
Can read multisession: 1 1 1
Can read MCN: 1 1 1
Reports media changed: 1 1 1
Can play audio: 1 1 1
Can write CD-R: 0 1 1
Can write CD-RW: 0 1 1
Can read DVD: 1 0 0
Can write DVD-R: 0 0 0
Can write DVD-RAM: 1 0 0
Can read MRW: 0 0 1
Can write MRW: 0 0 1

The one I'm mounting is /dev/scd1.
As there is capablity to write-protect DVD-RAM disk (like a 1.44"
Floppy), I think that the linux kernel interprets some message from
device in wrong way.

Regards,

Olaf


2004-03-05 20:54:56

by Daniel Egger

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Mar 5, 2004, at 12:45 pm, Olaf Frączyk wrote:

CD-ROM information, Id: cdrom.c 3.20 2003/12/17

drive name: hdc
drive speed: 63
drive # of slots: 1
Can close tray: 1
Can open tray: 1
Can lock tray: 1
Can change speed: 1
Can select disk: 0
Can read multisession: 1
Can read MCN: 1
Reports media changed: 1
Can play audio: 1
Can write CD-R: 1
Can write CD-RW: 1
Can read DVD: 1
Can write DVD-R: 1
Can write DVD-RAM: 1
Can read MRW: 0
Can write MRW: 0

DVD-RAM mounting works for me.

However shouldn't this table also contain DVD-RW, DVD+R and DVD+RW?

This is a LG 4040B which is capable of this formats also.

Servus,
Daniel


Attachments:
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2004-03-07 10:59:15

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > Hi,
> > > I switched to 2.6.3 from 2.4.x serie.
> > > When I mount DVD-RAM it is mounted read-only:
> > >
> > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > [root@venus olaf]#
> > >
> > > In 2.4 it is mounted correctly as read-write.
> > >
> > > Drive: Panasonic LF-201, reported in Linux as:
> > > MATSHITA DVD-RAM LF-D200 A120
> > >
> > > SCSI controller: Adaptec 2940U2W
> >
> > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > messages in dmesg when the rw mount fails?
>
> I get nothing in /var/log/dmesg and in /var/log/messages
> In /proc/sys/dev/cdrom/info I get:
> [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> CD-ROM information, Id: cdrom.c 3.20 2003/12/17
>
> drive name: sr1 sr0 hdc
> drive speed: 0 16 44
> drive # of slots: 1 1 1
> Can close tray: 1 1 1
> Can open tray: 1 1 1
> Can lock tray: 1 1 1
> Can change speed: 1 1 1
> Can select disk: 0 0 0
> Can read multisession: 1 1 1
> Can read MCN: 1 1 1
> Reports media changed: 1 1 1
> Can play audio: 1 1 1
> Can write CD-R: 0 1 1
> Can write CD-RW: 0 1 1
> Can read DVD: 1 0 0
> Can write DVD-R: 0 0 0
> Can write DVD-RAM: 1 0 0
> Can read MRW: 0 0 1
> Can write MRW: 0 0 1
>
> The one I'm mounting is /dev/scd1.
> As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> Floppy), I think that the linux kernel interprets some message from
> device in wrong way.

Please repeat with this patch applied and send back the results, thanks.

===== drivers/cdrom/cdrom.c 1.48 vs edited =====
--- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
+++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
@@ -645,9 +645,12 @@
{
disc_information di;

- if (cdrom_get_disc_info(cdi, &di))
+ if (cdrom_get_disc_info(cdi, &di)) {
+ printk("cdrom: read di failed\n");
return 0;
+ }

+ printk("cdrom: erasable: %d\n", di.erasable);
return di.erasable;
}


--
Jens Axboe

2004-03-09 07:55:42

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > Hi,
> > > > I switched to 2.6.3 from 2.4.x serie.
> > > > When I mount DVD-RAM it is mounted read-only:
> > > >
> > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > [root@venus olaf]#
> > > >
> > > > In 2.4 it is mounted correctly as read-write.
> > > >
> > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > MATSHITA DVD-RAM LF-D200 A120
> > > >
> > > > SCSI controller: Adaptec 2940U2W
> > >
> > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > messages in dmesg when the rw mount fails?
> >
> > I get nothing in /var/log/dmesg and in /var/log/messages
> > In /proc/sys/dev/cdrom/info I get:
> > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> >
> > drive name: sr1 sr0 hdc
> > drive speed: 0 16 44
> > drive # of slots: 1 1 1
> > Can close tray: 1 1 1
> > Can open tray: 1 1 1
> > Can lock tray: 1 1 1
> > Can change speed: 1 1 1
> > Can select disk: 0 0 0
> > Can read multisession: 1 1 1
> > Can read MCN: 1 1 1
> > Reports media changed: 1 1 1
> > Can play audio: 1 1 1
> > Can write CD-R: 0 1 1
> > Can write CD-RW: 0 1 1
> > Can read DVD: 1 0 0
> > Can write DVD-R: 0 0 0
> > Can write DVD-RAM: 1 0 0
> > Can read MRW: 0 0 1
> > Can write MRW: 0 0 1
> >
> > The one I'm mounting is /dev/scd1.
> > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > Floppy), I think that the linux kernel interprets some message from
> > device in wrong way.
>
> Please repeat with this patch applied and send back the results, thanks.
>
> ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> --- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> @@ -645,9 +645,12 @@
> {
> disc_information di;
>
> - if (cdrom_get_disc_info(cdi, &di))
> + if (cdrom_get_disc_info(cdi, &di)) {
> + printk("cdrom: read di failed\n");
> return 0;
> + }
>
> + printk("cdrom: erasable: %d\n", di.erasable);
> return di.erasable;
> }
>
I get:
cdrom: read di failed

Regards,

Olaf

2004-03-09 09:12:28

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > Hi,
> > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > When I mount DVD-RAM it is mounted read-only:
> > > > >
> > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > [root@venus olaf]#
> > > > >
> > > > > In 2.4 it is mounted correctly as read-write.
> > > > >
> > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > >
> > > > > SCSI controller: Adaptec 2940U2W
> > > >
> > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > messages in dmesg when the rw mount fails?
> > >
> > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > In /proc/sys/dev/cdrom/info I get:
> > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > >
> > > drive name: sr1 sr0 hdc
> > > drive speed: 0 16 44
> > > drive # of slots: 1 1 1
> > > Can close tray: 1 1 1
> > > Can open tray: 1 1 1
> > > Can lock tray: 1 1 1
> > > Can change speed: 1 1 1
> > > Can select disk: 0 0 0
> > > Can read multisession: 1 1 1
> > > Can read MCN: 1 1 1
> > > Reports media changed: 1 1 1
> > > Can play audio: 1 1 1
> > > Can write CD-R: 0 1 1
> > > Can write CD-RW: 0 1 1
> > > Can read DVD: 1 0 0
> > > Can write DVD-R: 0 0 0
> > > Can write DVD-RAM: 1 0 0
> > > Can read MRW: 0 0 1
> > > Can write MRW: 0 0 1
> > >
> > > The one I'm mounting is /dev/scd1.
> > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > Floppy), I think that the linux kernel interprets some message from
> > > device in wrong way.
> >
> > Please repeat with this patch applied and send back the results, thanks.
> >
> > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > --- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > @@ -645,9 +645,12 @@
> > {
> > disc_information di;
> >
> > - if (cdrom_get_disc_info(cdi, &di))
> > + if (cdrom_get_disc_info(cdi, &di)) {
> > + printk("cdrom: read di failed\n");
> > return 0;
> > + }
> >
> > + printk("cdrom: erasable: %d\n", di.erasable);
> > return di.erasable;
> > }
> >
> I get:
> cdrom: read di failed

Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
as well (that alone might be enough to pin point the problem).

--
Jens Axboe

2004-03-11 01:53:01

by Thomas Duda

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

Hi,

to me this seems to be a problem with dvdram drives connected to a scsi
hba.
I've got exactly the same software setup based on 2.6.2 on 3 systems
with
a dvdram drive. One is a Panasonic LFD-201 (SCSI), another one is a
Panasonic
LFD-521 (IDE), the third is an LG-4020B (IDE).

The SCSI LFD-201 is connected to an Adaptec 7890. There is no way I can
use it to write data. A mount always happens read-only. Even though "Can
write DVD-RAM" is reported in /proc/sys/dev/cdrom/info.

Another phenomen: mkfs.ext2 /dev/scd0 runs as usual. No errors or any
other messages. The drive led lightens up. However - the dvdram doesn't
have
an ext2 fs afterwards. If I do a tune2fs -c 0 -t 0 /dev/scd0 it tells me
"bad superblock".

The 2 IDE dvdram drives in the other machines perform the task as
expected.

If I take the dvdram out of the scsi drive into the ide drives, format
it with mkfs.ext2, put it back into the scsi drive, then I see an ext2
fs
on it.

Just for clarification: They all workfine with all their speced out
capabilities
with plain Suse 9.0 out-of-the-box! (off-course with ide-scsi, kernel
2.4.21-192)

To me this looks like a problem in 2.6.2/3 with scsi connected dvdram
drives only..?
So may be the problem lies not in the cdrom stuff but in interfacing
that to the
scsi layer..?

As a remark: I noticed that /proc/sys/dev/cdrom/info doesn't report
anything
related to dvd-rw nor dvd+rw write capabilites for the ide based LG
GSA-4040B
or the Panasonic LFD-521E (dvd-rw only!). Is this intentional?

regs

td


Jens Axboe schrieb:
>
> On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > Hi,
> > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > >
> > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > [root@venus olaf]#
> > > > > >
> > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > >
> > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > >
> > > > > > SCSI controller: Adaptec 2940U2W
> > > > >
> > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > messages in dmesg when the rw mount fails?
> > > >
> > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > In /proc/sys/dev/cdrom/info I get:
> > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > >
> > > > drive name: sr1 sr0 hdc
> > > > drive speed: 0 16 44
> > > > drive # of slots: 1 1 1
> > > > Can close tray: 1 1 1
> > > > Can open tray: 1 1 1
> > > > Can lock tray: 1 1 1
> > > > Can change speed: 1 1 1
> > > > Can select disk: 0 0 0
> > > > Can read multisession: 1 1 1
> > > > Can read MCN: 1 1 1
> > > > Reports media changed: 1 1 1
> > > > Can play audio: 1 1 1
> > > > Can write CD-R: 0 1 1
> > > > Can write CD-RW: 0 1 1
> > > > Can read DVD: 1 0 0
> > > > Can write DVD-R: 0 0 0
> > > > Can write DVD-RAM: 1 0 0
> > > > Can read MRW: 0 0 1
> > > > Can write MRW: 0 0 1
> > > >
> > > > The one I'm mounting is /dev/scd1.
> > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > Floppy), I think that the linux kernel interprets some message from
> > > > device in wrong way.
> > >
> > > Please repeat with this patch applied and send back the results, thanks.
> > >
> > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > --- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > @@ -645,9 +645,12 @@
> > > {
> > > disc_information di;
> > >
> > > - if (cdrom_get_disc_info(cdi, &di))
> > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > + printk("cdrom: read di failed\n");
> > > return 0;
> > > + }
> > >
> > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > return di.erasable;
> > > }
> > >
> > I get:
> > cdrom: read di failed
>
> Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> as well (that alone might be enough to pin point the problem).
>
> --
> Jens Axboe
>
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/

2004-03-14 11:13:12

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Tue, 2004-03-09 at 10:12, Jens Axboe wrote:
> On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > Hi,
> > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > >
> > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > [root@venus olaf]#
> > > > > >
> > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > >
> > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > >
> > > > > > SCSI controller: Adaptec 2940U2W
> > > > >
> > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > messages in dmesg when the rw mount fails?
> > > >
> > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > In /proc/sys/dev/cdrom/info I get:
> > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > >
> > > > drive name: sr1 sr0 hdc
> > > > drive speed: 0 16 44
> > > > drive # of slots: 1 1 1
> > > > Can close tray: 1 1 1
> > > > Can open tray: 1 1 1
> > > > Can lock tray: 1 1 1
> > > > Can change speed: 1 1 1
> > > > Can select disk: 0 0 0
> > > > Can read multisession: 1 1 1
> > > > Can read MCN: 1 1 1
> > > > Reports media changed: 1 1 1
> > > > Can play audio: 1 1 1
> > > > Can write CD-R: 0 1 1
> > > > Can write CD-RW: 0 1 1
> > > > Can read DVD: 1 0 0
> > > > Can write DVD-R: 0 0 0
> > > > Can write DVD-RAM: 1 0 0
> > > > Can read MRW: 0 0 1
> > > > Can write MRW: 0 0 1
> > > >
> > > > The one I'm mounting is /dev/scd1.
> > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > Floppy), I think that the linux kernel interprets some message from
> > > > device in wrong way.
> > >
> > > Please repeat with this patch applied and send back the results, thanks.
> > >
> > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > -- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > @@ -645,9 +645,12 @@
> > > {
> > > disc_information di;
> > >
> > > - if (cdrom_get_disc_info(cdi, &di))
> > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > + printk("cdrom: read di failed\n");
> > > return 0;
> > > + }
> > >
> > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > return di.erasable;
> > > }
> > >
> > I get:
> > cdrom: read di failed
>
> Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> as well (that alone might be enough to pin point the problem).
Sorry for the delay. I couldn't take tha machine down.
After setting cgc.quiet=0 I get no additional messages from kernel.
cdrom_get_disc_info returns after FIRST:
cdo->generic_packet(cdi, &cgc).

BTW, I suppose return codes are interpreted not well:
In cdrom_get_disc_info we return after first (cdo->generic_packet) if it
returns not 0. (Success?) And we return with not 0 value.
And in cdrom_media_erasable we assume that not 0 is error, not success.
So probably in cdrom_get_disc_info we should have:
if (!(ret = cdo->generic_packet(cdi, &cgc)))
return ret;

I tried it, but it changed nothing regarding to the problem.
It returns then after second cdo->generic_packet, but I still get:
read di failed.

Regards,

Olaf

2004-03-14 11:23:24

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected


BTW, both of you please use 2.6.4 as the base, not 2.6.3. The latter has
some other scsi problems that could affect this.

On Sun, Mar 14 2004, Jens Axboe wrote:
> On Sun, Mar 14 2004, Olaf Fr?czyk wrote:
> > On Tue, 2004-03-09 at 10:12, Jens Axboe wrote:
> > > On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > > > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > > > Hi,
> > > > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > > > >
> > > > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > > > [root@venus olaf]#
> > > > > > > >
> > > > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > > > >
> > > > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > > > >
> > > > > > > > SCSI controller: Adaptec 2940U2W
> > > > > > >
> > > > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > > > messages in dmesg when the rw mount fails?
> > > > > >
> > > > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > > > In /proc/sys/dev/cdrom/info I get:
> > > > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > > > >
> > > > > > drive name: sr1 sr0 hdc
> > > > > > drive speed: 0 16 44
> > > > > > drive # of slots: 1 1 1
> > > > > > Can close tray: 1 1 1
> > > > > > Can open tray: 1 1 1
> > > > > > Can lock tray: 1 1 1
> > > > > > Can change speed: 1 1 1
> > > > > > Can select disk: 0 0 0
> > > > > > Can read multisession: 1 1 1
> > > > > > Can read MCN: 1 1 1
> > > > > > Reports media changed: 1 1 1
> > > > > > Can play audio: 1 1 1
> > > > > > Can write CD-R: 0 1 1
> > > > > > Can write CD-RW: 0 1 1
> > > > > > Can read DVD: 1 0 0
> > > > > > Can write DVD-R: 0 0 0
> > > > > > Can write DVD-RAM: 1 0 0
> > > > > > Can read MRW: 0 0 1
> > > > > > Can write MRW: 0 0 1
> > > > > >
> > > > > > The one I'm mounting is /dev/scd1.
> > > > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > > > Floppy), I think that the linux kernel interprets some message from
> > > > > > device in wrong way.
> > > > >
> > > > > Please repeat with this patch applied and send back the results, thanks.
> > > > >
> > > > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > > > -- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > > > @@ -645,9 +645,12 @@
> > > > > {
> > > > > disc_information di;
> > > > >
> > > > > - if (cdrom_get_disc_info(cdi, &di))
> > > > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > > > + printk("cdrom: read di failed\n");
> > > > > return 0;
> > > > > + }
> > > > >
> > > > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > > > return di.erasable;
> > > > > }
> > > > >
> > > > I get:
> > > > cdrom: read di failed
> > >
> > > Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> > > and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> > > as well (that alone might be enough to pin point the problem).
> > Sorry for the delay. I couldn't take tha machine down.
> > After setting cgc.quiet=0 I get no additional messages from kernel.
> > cdrom_get_disc_info returns after FIRST:
> > cdo->generic_packet(cdi, &cgc).
>
> Ok, at least that's a little clue... Maybe your drive is buggy (I think
> we already established that, question is what the bug is) and doesn't
> like to return just two bytes, please try with attached patch.
>
> > BTW, I suppose return codes are interpreted not well:
> > In cdrom_get_disc_info we return after first (cdo->generic_packet) if it
> > returns not 0. (Success?) And we return with not 0 value.
> > And in cdrom_media_erasable we assume that not 0 is error, not success.
> > So probably in cdrom_get_disc_info we should have:
> > if (!(ret = cdo->generic_packet(cdi, &cgc)))
> > return ret;
>
> No, you are not reading the code correctly. ->generic_packet() returns 0
> on success, or the error (standard kernel practice).
> cdrom_media_erasable() returns a bool, and if cdrom_get_disc_info()
> fails then we return it's not erasable.
>
> > I tried it, but it changed nothing regarding to the problem.
> > It returns then after second cdo->generic_packet, but I still get:
> > read di failed.
>
> You broke it, the first check simply returns the header so .erasable
> must be 0 because we cleared the buffer first.
>
> ===== drivers/cdrom/cdrom.c 1.49 vs edited =====
> --- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
> +++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
> @@ -2658,11 +2658,13 @@
> /* set up command and get the disc info */
> init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
> cgc.cmd[0] = GPCMD_READ_DISC_INFO;
> - cgc.cmd[8] = cgc.buflen = 2;
> - cgc.quiet = 1;
> + cgc.cmd[8] = cgc.buflen = 8;
> + cgc.quiet = 0;
>
> - if ((ret = cdo->generic_packet(cdi, &cgc)))
> + if ((ret = cdo->generic_packet(cdi, &cgc))) {
> + printk("cdrom: read_di failed, %d\n", ret);
> return ret;
> + }
>
> /* not all drives have the same disc_info length, so requeue
> * packet with the length the drive tells us it can supply
> @@ -2673,6 +2675,7 @@
> if (cgc.buflen > sizeof(disc_information))
> cgc.buflen = sizeof(disc_information);
>
> + printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
> cgc.cmd[8] = cgc.buflen;
> return cdo->generic_packet(cdi, &cgc);
> }
>
> --
> Jens Axboe
>

--
Jens Axboe

2004-03-14 11:22:20

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Sun, Mar 14 2004, Olaf Fr?czyk wrote:
> On Tue, 2004-03-09 at 10:12, Jens Axboe wrote:
> > On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > > Hi,
> > > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > > >
> > > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > > [root@venus olaf]#
> > > > > > >
> > > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > > >
> > > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > > >
> > > > > > > SCSI controller: Adaptec 2940U2W
> > > > > >
> > > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > > messages in dmesg when the rw mount fails?
> > > > >
> > > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > > In /proc/sys/dev/cdrom/info I get:
> > > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > > >
> > > > > drive name: sr1 sr0 hdc
> > > > > drive speed: 0 16 44
> > > > > drive # of slots: 1 1 1
> > > > > Can close tray: 1 1 1
> > > > > Can open tray: 1 1 1
> > > > > Can lock tray: 1 1 1
> > > > > Can change speed: 1 1 1
> > > > > Can select disk: 0 0 0
> > > > > Can read multisession: 1 1 1
> > > > > Can read MCN: 1 1 1
> > > > > Reports media changed: 1 1 1
> > > > > Can play audio: 1 1 1
> > > > > Can write CD-R: 0 1 1
> > > > > Can write CD-RW: 0 1 1
> > > > > Can read DVD: 1 0 0
> > > > > Can write DVD-R: 0 0 0
> > > > > Can write DVD-RAM: 1 0 0
> > > > > Can read MRW: 0 0 1
> > > > > Can write MRW: 0 0 1
> > > > >
> > > > > The one I'm mounting is /dev/scd1.
> > > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > > Floppy), I think that the linux kernel interprets some message from
> > > > > device in wrong way.
> > > >
> > > > Please repeat with this patch applied and send back the results, thanks.
> > > >
> > > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > > -- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > > @@ -645,9 +645,12 @@
> > > > {
> > > > disc_information di;
> > > >
> > > > - if (cdrom_get_disc_info(cdi, &di))
> > > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > > + printk("cdrom: read di failed\n");
> > > > return 0;
> > > > + }
> > > >
> > > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > > return di.erasable;
> > > > }
> > > >
> > > I get:
> > > cdrom: read di failed
> >
> > Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> > and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> > as well (that alone might be enough to pin point the problem).
> Sorry for the delay. I couldn't take tha machine down.
> After setting cgc.quiet=0 I get no additional messages from kernel.
> cdrom_get_disc_info returns after FIRST:
> cdo->generic_packet(cdi, &cgc).

Ok, at least that's a little clue... Maybe your drive is buggy (I think
we already established that, question is what the bug is) and doesn't
like to return just two bytes, please try with attached patch.

> BTW, I suppose return codes are interpreted not well:
> In cdrom_get_disc_info we return after first (cdo->generic_packet) if it
> returns not 0. (Success?) And we return with not 0 value.
> And in cdrom_media_erasable we assume that not 0 is error, not success.
> So probably in cdrom_get_disc_info we should have:
> if (!(ret = cdo->generic_packet(cdi, &cgc)))
> return ret;

No, you are not reading the code correctly. ->generic_packet() returns 0
on success, or the error (standard kernel practice).
cdrom_media_erasable() returns a bool, and if cdrom_get_disc_info()
fails then we return it's not erasable.

> I tried it, but it changed nothing regarding to the problem.
> It returns then after second cdo->generic_packet, but I still get:
> read di failed.

You broke it, the first check simply returns the header so .erasable
must be 0 because we cleared the buffer first.

===== drivers/cdrom/cdrom.c 1.49 vs edited =====
--- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
+++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
@@ -2658,11 +2658,13 @@
/* set up command and get the disc info */
init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
cgc.cmd[0] = GPCMD_READ_DISC_INFO;
- cgc.cmd[8] = cgc.buflen = 2;
- cgc.quiet = 1;
+ cgc.cmd[8] = cgc.buflen = 8;
+ cgc.quiet = 0;

- if ((ret = cdo->generic_packet(cdi, &cgc)))
+ if ((ret = cdo->generic_packet(cdi, &cgc))) {
+ printk("cdrom: read_di failed, %d\n", ret);
return ret;
+ }

/* not all drives have the same disc_info length, so requeue
* packet with the length the drive tells us it can supply
@@ -2673,6 +2675,7 @@
if (cgc.buflen > sizeof(disc_information))
cgc.buflen = sizeof(disc_information);

+ printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
cgc.cmd[8] = cgc.buflen;
return cdo->generic_packet(cdi, &cgc);
}

--
Jens Axboe

2004-03-23 14:46:03

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Sun, 2004-03-14 at 12:22, Jens Axboe wrote:
> On Sun, Mar 14 2004, Olaf Fr?czyk wrote:
> > On Tue, 2004-03-09 at 10:12, Jens Axboe wrote:
> > > On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > > > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > > > Hi,
> > > > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > > > >
> > > > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > > > [root@venus olaf]#
> > > > > > > >
> > > > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > > > >
> > > > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > > > >
> > > > > > > > SCSI controller: Adaptec 2940U2W
> > > > > > >
> > > > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > > > messages in dmesg when the rw mount fails?
> > > > > >
> > > > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > > > In /proc/sys/dev/cdrom/info I get:
> > > > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > > > >
> > > > > > drive name: sr1 sr0 hdc
> > > > > > drive speed: 0 16 44
> > > > > > drive # of slots: 1 1 1
> > > > > > Can close tray: 1 1 1
> > > > > > Can open tray: 1 1 1
> > > > > > Can lock tray: 1 1 1
> > > > > > Can change speed: 1 1 1
> > > > > > Can select disk: 0 0 0
> > > > > > Can read multisession: 1 1 1
> > > > > > Can read MCN: 1 1 1
> > > > > > Reports media changed: 1 1 1
> > > > > > Can play audio: 1 1 1
> > > > > > Can write CD-R: 0 1 1
> > > > > > Can write CD-RW: 0 1 1
> > > > > > Can read DVD: 1 0 0
> > > > > > Can write DVD-R: 0 0 0
> > > > > > Can write DVD-RAM: 1 0 0
> > > > > > Can read MRW: 0 0 1
> > > > > > Can write MRW: 0 0 1
> > > > > >
> > > > > > The one I'm mounting is /dev/scd1.
> > > > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > > > Floppy), I think that the linux kernel interprets some message from
> > > > > > device in wrong way.
> > > > >
> > > > > Please repeat with this patch applied and send back the results, thanks.
> > > > >
> > > > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > > > -- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > > > @@ -645,9 +645,12 @@
> > > > > {
> > > > > disc_information di;
> > > > >
> > > > > - if (cdrom_get_disc_info(cdi, &di))
> > > > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > > > + printk("cdrom: read di failed\n");
> > > > > return 0;
> > > > > + }
> > > > >
> > > > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > > > return di.erasable;
> > > > > }
> > > > >
> > > > I get:
> > > > cdrom: read di failed
> > >
> > > Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> > > and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> > > as well (that alone might be enough to pin point the problem).
> > Sorry for the delay. I couldn't take tha machine down.
> > After setting cgc.quiet=0 I get no additional messages from kernel.
> > cdrom_get_disc_info returns after FIRST:
> > cdo->generic_packet(cdi, &cgc).
>
> Ok, at least that's a little clue... Maybe your drive is buggy (I think
> we already established that, question is what the bug is) and doesn't
> like to return just two bytes, please try with attached patch.
>
> > BTW, I suppose return codes are interpreted not well:
> > In cdrom_get_disc_info we return after first (cdo->generic_packet) if it
> > returns not 0. (Success?) And we return with not 0 value.
> > And in cdrom_media_erasable we assume that not 0 is error, not success.
> > So probably in cdrom_get_disc_info we should have:
> > if (!(ret = cdo->generic_packet(cdi, &cgc)))
> > return ret;
>
> No, you are not reading the code correctly. ->generic_packet() returns 0
> on success, or the error (standard kernel practice).
> cdrom_media_erasable() returns a bool, and if cdrom_get_disc_info()
> fails then we return it's not erasable.
>
> > I tried it, but it changed nothing regarding to the problem.
> > It returns then after second cdo->generic_packet, but I still get:
> > read di failed.
>
> You broke it, the first check simply returns the header so .erasable
> must be 0 because we cleared the buffer first.
>
> ===== drivers/cdrom/cdrom.c 1.49 vs edited =====
> --- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
> +++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
> @@ -2658,11 +2658,13 @@
> /* set up command and get the disc info */
> init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
> cgc.cmd[0] = GPCMD_READ_DISC_INFO;
> - cgc.cmd[8] = cgc.buflen = 2;
> - cgc.quiet = 1;
> + cgc.cmd[8] = cgc.buflen = 8;
> + cgc.quiet = 0;
>
> - if ((ret = cdo->generic_packet(cdi, &cgc)))
> + if ((ret = cdo->generic_packet(cdi, &cgc))) {
> + printk("cdrom: read_di failed, %d\n", ret);
> return ret;
> + }
>
> /* not all drives have the same disc_info length, so requeue
> * packet with the length the drive tells us it can supply
> @@ -2673,6 +2675,7 @@
> if (cgc.buflen > sizeof(disc_information))
> cgc.buflen = sizeof(disc_information);
>
> + printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
> cgc.cmd[8] = cgc.buflen;
> return cdo->generic_packet(cdi, &cgc);
> }
On 2.6.4 with your patch I get:
Mar 23 15:46:03 venus kernel: cdrom: read_di failed, -95

Regards,

Olaf

2004-03-23 15:23:46

by Jens Axboe

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Tue, Mar 23 2004, Olaf Fr?czyk wrote:
> > You broke it, the first check simply returns the header so .erasable
> > must be 0 because we cleared the buffer first.
> >
> > ===== drivers/cdrom/cdrom.c 1.49 vs edited =====
> > --- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
> > +++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
> > @@ -2658,11 +2658,13 @@
> > /* set up command and get the disc info */
> > init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
> > cgc.cmd[0] = GPCMD_READ_DISC_INFO;
> > - cgc.cmd[8] = cgc.buflen = 2;
> > - cgc.quiet = 1;
> > + cgc.cmd[8] = cgc.buflen = 8;
> > + cgc.quiet = 0;
> >
> > - if ((ret = cdo->generic_packet(cdi, &cgc)))
> > + if ((ret = cdo->generic_packet(cdi, &cgc))) {
> > + printk("cdrom: read_di failed, %d\n", ret);
> > return ret;
> > + }
> >
> > /* not all drives have the same disc_info length, so requeue
> > * packet with the length the drive tells us it can supply
> > @@ -2673,6 +2675,7 @@
> > if (cgc.buflen > sizeof(disc_information))
> > cgc.buflen = sizeof(disc_information);
> >
> > + printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
> > cgc.cmd[8] = cgc.buflen;
> > return cdo->generic_packet(cdi, &cgc);
> > }
> On 2.6.4 with your patch I get:
> Mar 23 15:46:03 venus kernel: cdrom: read_di failed, -95

Ok, so your drive doesn't support GPCMD_READ_DISC_INFO at all. Probably
the best bet is simply to allow writable open if cdrom_get_disc_info()
fails after all, even though I hate doing stuff like that.

===== drivers/cdrom/cdrom.c 1.50 vs edited =====
--- 1.50/drivers/cdrom/cdrom.c Tue Mar 16 09:41:01 2004
+++ edited/drivers/cdrom/cdrom.c Tue Mar 23 16:23:07 2004
@@ -725,7 +725,7 @@
disc_information di;

if (cdrom_get_disc_info(cdi, &di))
- return 0;
+ return -1;

return di.erasable;
}
@@ -735,7 +735,16 @@
*/
static int cdrom_dvdram_open_write(struct cdrom_device_info *cdi)
{
- return !cdrom_media_erasable(cdi);
+ int ret = cdrom_media_erasable(cdi);
+
+ /*
+ * allow writable open if media info read worked and media is
+ * erasable, _or_ if it fails since not all drives support it
+ */
+ if (!ret)
+ return 1;
+
+ return 0;
}

static int cdrom_mrw_open_write(struct cdrom_device_info *cdi)

--
Jens Axboe

2004-03-23 15:28:34

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Tue, 2004-03-23 at 15:50, Olaf Frączyk wrote:
> On Sun, 2004-03-14 at 12:22, Jens Axboe wrote:
> > On Sun, Mar 14 2004, Olaf Fr?czyk wrote:
> > > On Tue, 2004-03-09 at 10:12, Jens Axboe wrote:
> > > > On Tue, Mar 09 2004, Olaf Fr?czyk wrote:
> > > > > On Sun, 2004-03-07 at 11:59, Jens Axboe wrote:
> > > > > > On Fri, Mar 05 2004, Olaf Fr?czyk wrote:
> > > > > > > On Fri, 2004-03-05 at 09:23, Jens Axboe wrote:
> > > > > > > > On Thu, Mar 04 2004, Olaf Fr?czyk wrote:
> > > > > > > > > Hi,
> > > > > > > > > I switched to 2.6.3 from 2.4.x serie.
> > > > > > > > > When I mount DVD-RAM it is mounted read-only:
> > > > > > > > >
> > > > > > > > > [root@venus olaf]# mount /dev/dvdram /mnt/dvdram
> > > > > > > > > mount: block device /dev/dvdram is write-protected, mounting read-only
> > > > > > > > > [root@venus olaf]#
> > > > > > > > >
> > > > > > > > > In 2.4 it is mounted correctly as read-write.
> > > > > > > > >
> > > > > > > > > Drive: Panasonic LF-201, reported in Linux as:
> > > > > > > > > MATSHITA DVD-RAM LF-D200 A120
> > > > > > > > >
> > > > > > > > > SCSI controller: Adaptec 2940U2W
> > > > > > > >
> > > > > > > > What does cat /proc/sys/dev/cdrom/info say? Do you get any kernel
> > > > > > > > messages in dmesg when the rw mount fails?
> > > > > > >
> > > > > > > I get nothing in /var/log/dmesg and in /var/log/messages
> > > > > > > In /proc/sys/dev/cdrom/info I get:
> > > > > > > [olaf@venus olaf]$ cat /proc/sys/dev/cdrom/info
> > > > > > > CD-ROM information, Id: cdrom.c 3.20 2003/12/17
> > > > > > >
> > > > > > > drive name: sr1 sr0 hdc
> > > > > > > drive speed: 0 16 44
> > > > > > > drive # of slots: 1 1 1
> > > > > > > Can close tray: 1 1 1
> > > > > > > Can open tray: 1 1 1
> > > > > > > Can lock tray: 1 1 1
> > > > > > > Can change speed: 1 1 1
> > > > > > > Can select disk: 0 0 0
> > > > > > > Can read multisession: 1 1 1
> > > > > > > Can read MCN: 1 1 1
> > > > > > > Reports media changed: 1 1 1
> > > > > > > Can play audio: 1 1 1
> > > > > > > Can write CD-R: 0 1 1
> > > > > > > Can write CD-RW: 0 1 1
> > > > > > > Can read DVD: 1 0 0
> > > > > > > Can write DVD-R: 0 0 0
> > > > > > > Can write DVD-RAM: 1 0 0
> > > > > > > Can read MRW: 0 0 1
> > > > > > > Can write MRW: 0 0 1
> > > > > > >
> > > > > > > The one I'm mounting is /dev/scd1.
> > > > > > > As there is capablity to write-protect DVD-RAM disk (like a 1.44"
> > > > > > > Floppy), I think that the linux kernel interprets some message from
> > > > > > > device in wrong way.
> > > > > >
> > > > > > Please repeat with this patch applied and send back the results, thanks.
> > > > > >
> > > > > > ===== drivers/cdrom/cdrom.c 1.48 vs edited =====
> > > > > > -- 1.48/drivers/cdrom/cdrom.c Mon Feb 9 21:58:21 2004
> > > > > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 7 11:58:40 2004
> > > > > > @@ -645,9 +645,12 @@
> > > > > > {
> > > > > > disc_information di;
> > > > > >
> > > > > > - if (cdrom_get_disc_info(cdi, &di))
> > > > > > + if (cdrom_get_disc_info(cdi, &di)) {
> > > > > > + printk("cdrom: read di failed\n");
> > > > > > return 0;
> > > > > > + }
> > > > > >
> > > > > > + printk("cdrom: erasable: %d\n", di.erasable);
> > > > > > return di.erasable;
> > > > > > }
> > > > > >
> > > > > I get:
> > > > > cdrom: read di failed
> > > >
> > > > Can you try to instrument drivers/cdrom/cdrom.c:cdrom_get_disc_info()
> > > > and find out where it fails? Change the cgc.quiet = 1 to a = 0 in there
> > > > as well (that alone might be enough to pin point the problem).
> > > Sorry for the delay. I couldn't take tha machine down.
> > > After setting cgc.quiet=0 I get no additional messages from kernel.
> > > cdrom_get_disc_info returns after FIRST:
> > > cdo->generic_packet(cdi, &cgc).
> >
> > Ok, at least that's a little clue... Maybe your drive is buggy (I think
> > we already established that, question is what the bug is) and doesn't
> > like to return just two bytes, please try with attached patch.
> >
> > > BTW, I suppose return codes are interpreted not well:
> > > In cdrom_get_disc_info we return after first (cdo->generic_packet) if it
> > > returns not 0. (Success?) And we return with not 0 value.
> > > And in cdrom_media_erasable we assume that not 0 is error, not success.
> > > So probably in cdrom_get_disc_info we should have:
> > > if (!(ret = cdo->generic_packet(cdi, &cgc)))
> > > return ret;
> >
> > No, you are not reading the code correctly. ->generic_packet() returns 0
> > on success, or the error (standard kernel practice).
> > cdrom_media_erasable() returns a bool, and if cdrom_get_disc_info()
> > fails then we return it's not erasable.
> >
> > > I tried it, but it changed nothing regarding to the problem.
> > > It returns then after second cdo->generic_packet, but I still get:
> > > read di failed.
> >
> > You broke it, the first check simply returns the header so .erasable
> > must be 0 because we cleared the buffer first.
> >
> > ===== drivers/cdrom/cdrom.c 1.49 vs edited =====
> > --- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
> > +++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
> > @@ -2658,11 +2658,13 @@
> > /* set up command and get the disc info */
> > init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
> > cgc.cmd[0] = GPCMD_READ_DISC_INFO;
> > - cgc.cmd[8] = cgc.buflen = 2;
> > - cgc.quiet = 1;
> > + cgc.cmd[8] = cgc.buflen = 8;
> > + cgc.quiet = 0;
> >
> > - if ((ret = cdo->generic_packet(cdi, &cgc)))
> > + if ((ret = cdo->generic_packet(cdi, &cgc))) {
> > + printk("cdrom: read_di failed, %d\n", ret);
> > return ret;
> > + }
> >
> > /* not all drives have the same disc_info length, so requeue
> > * packet with the length the drive tells us it can supply
> > @@ -2673,6 +2675,7 @@
> > if (cgc.buflen > sizeof(disc_information))
> > cgc.buflen = sizeof(disc_information);
> >
> > + printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
> > cgc.cmd[8] = cgc.buflen;
> > return cdo->generic_packet(cdi, &cgc);
> > }
> On 2.6.4 with your patch I get:
> Mar 23 15:46:03 venus kernel: cdrom: read_di failed, -95
I have found, that I can't mount CD in my Yamaha 6416S now. It worked
with 2.6.3. So we have two problems now. Should I start separate thread
or continue here?

When I try to mount CD I get in command line:
[root@venus scsi]# mount /dev/scd0 /mnt/cdrom
/dev/scd0: Invalid argument
mount: block device /dev/scd0 is write-protected, mounting read-only
/dev/scd0: Invalid argument
mount: /dev/scd0: can't read superblock

And in /var/log/messages:
Mar 23 16:23:08 venus kernel: end_request: I/O error, dev sr0, sector 0
Mar 23 16:23:08 venus kernel: FAT: unable to read boot sector

Regards,

Olaf



2004-03-23 15:31:48

by Olaf Frączyk

[permalink] [raw]
Subject: Re: 2.6.3 BUG - can't write DVD-RAM - reported as write-protected

On Tue, 2004-03-23 at 16:23, Jens Axboe wrote:
> On Tue, Mar 23 2004, Olaf Fr?czyk wrote:
> > > You broke it, the first check simply returns the header so .erasable
> > > must be 0 because we cleared the buffer first.
> > >
> > > ===== drivers/cdrom/cdrom.c 1.49 vs edited =====
> > > --- 1.49/drivers/cdrom/cdrom.c Thu Mar 11 13:31:15 2004
> > > +++ edited/drivers/cdrom/cdrom.c Sun Mar 14 12:21:44 2004
> > > @@ -2658,11 +2658,13 @@
> > > /* set up command and get the disc info */
> > > init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
> > > cgc.cmd[0] = GPCMD_READ_DISC_INFO;
> > > - cgc.cmd[8] = cgc.buflen = 2;
> > > - cgc.quiet = 1;
> > > + cgc.cmd[8] = cgc.buflen = 8;
> > > + cgc.quiet = 0;
> > >
> > > - if ((ret = cdo->generic_packet(cdi, &cgc)))
> > > + if ((ret = cdo->generic_packet(cdi, &cgc))) {
> > > + printk("cdrom: read_di failed, %d\n", ret);
> > > return ret;
> > > + }
> > >
> > > /* not all drives have the same disc_info length, so requeue
> > > * packet with the length the drive tells us it can supply
> > > @@ -2673,6 +2675,7 @@
> > > if (cgc.buflen > sizeof(disc_information))
> > > cgc.buflen = sizeof(disc_information);
> > >
> > > + printk("cdrom: re-reading di, len=%d\n", cgc.buflen);
> > > cgc.cmd[8] = cgc.buflen;
> > > return cdo->generic_packet(cdi, &cgc);
> > > }
> > On 2.6.4 with your patch I get:
> > Mar 23 15:46:03 venus kernel: cdrom: read_di failed, -95
>
> Ok, so your drive doesn't support GPCMD_READ_DISC_INFO at all. Probably
> the best bet is simply to allow writable open if cdrom_get_disc_info()
> fails after all, even though I hate doing stuff like that.
>
> ===== drivers/cdrom/cdrom.c 1.50 vs edited =====
> --- 1.50/drivers/cdrom/cdrom.c Tue Mar 16 09:41:01 2004
> +++ edited/drivers/cdrom/cdrom.c Tue Mar 23 16:23:07 2004
> @@ -725,7 +725,7 @@
> disc_information di;
>
> if (cdrom_get_disc_info(cdi, &di))
> - return 0;
> + return -1;
>
> return di.erasable;
> }
> @@ -735,7 +735,16 @@
> */
> static int cdrom_dvdram_open_write(struct cdrom_device_info *cdi)
> {
> - return !cdrom_media_erasable(cdi);
> + int ret = cdrom_media_erasable(cdi);
> +
> + /*
> + * allow writable open if media info read worked and media is
> + * erasable, _or_ if it fails since not all drives support it
> + */
> + if (!ret)
> + return 1;
> +
> + return 0;
> }
>
> static int cdrom_mrw_open_write(struct cdrom_device_info *cdi)
Just to be sure. In 2.4 it was not checked?
Will your patch go in 2.6.5/2.6.6 or I'll have to patch it manually till
end of my life ? :)
Regards,

Olaf