Linux-kernel mailing list archive 1999-34,: DVD-RAM-Support in CD-ROM driver?

# DVD-RAM-Support in CD-ROM driver?

Michael Mess (michael@kawo2.rwth-aachen.de)
Mon, 23 Aug 1999 10:48:11 +0200

- Messages sorted by: [ date ][ thread ][ subject ][ author ]
- Next message: Dan Hollis: "Re: DVD-RAM-Support in CD-ROM driver?"
- Previous message: bart@etpmod.phys.tue.nl: "Improved IDT/Centaur WinChip detection patch"
- Next in thread: Michael Mess: "Re: DVD-RAM-Support in CD-ROM driver?"
- Reply: Michael Mess: "Re: DVD-RAM-Support in CD-ROM driver?"

Hi!

I own a Toshiba DVD-RAM drive (SCSI) and I would like to write to
DVD-RAM-Medium.
In Linux 2.2.9 I can read this medium without problems by using the
CDROM-driver (The drive identificates itself as CDROM-drive). When I try
to write to the medium, I get "READ ONLY FILESYSTEM" as error message.
I would like to modify the CDROM-driver to allow writing if a
DVD-RAM-medium is present and not write protected. When a DVD or CDROM
is in the drive the driver should behave like now.
So I can use this drive like a CDROM drive but when a DVD-RAM is in it,
I can write to that medium.

Where in the source-code is the decision about that "CDROM" is readonly?
Does it make sense to modify the CDROM driver or do I have to change
everything so that it would be better to write a separate driver?
What about the write behind cache of Linux? Are there any difficulties
with it, because the sector size of DVD-RAM is 2048?

I read that the CDROM-driver (sr.c) was taken from the SCSI disk driver
(sd.c).
What are the modifications from the SCSI disk driver? Is it possible to
take some routines for writing just from the SCSI disk driver (maybe
with modifications)?

Greetings, Michael

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/

- Next message: Dan Hollis: "Re: DVD-RAM-Support in CD-ROM driver?"
- Previous message: bart@etpmod.phys.tue.nl: "Improved IDT/Centaur WinChip detection patch"
- Next in thread: Michael Mess: "Re: DVD-RAM-Support in CD-ROM driver?"
- Reply: Michael Mess: "Re: DVD-RAM-Support in CD-ROM driver?"