cdrom blocksize reset bug with 2.4.x kernels

[Attila Kinali]

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Hi,

After some discussion on the mplayer-users mailinglist about
that for some scsi drives it's impossible to read a data cd
after reading a vcd/scvd until the next reboot.
(see http://mplayerhq.hu/pipermail/mplayer-users/2002-December/025696.html)

I found that there is a reset of the cdrom block size needed
for those drives which doesnt restet it themselfs if a new
cd is put in (looks like only a few scsi cdroms are affected)

Attached is a small patch for drivers/cdrom/cdrom.c that fixes=20
this for the 2.4.20 kernel (and also for 2.4.21 as the code didn't
change). It's reseting the blocksize when a cdrom is opened for
the first time (meaning that a umount/mount cycle can reset
the blocksize).

I run this code now for about half a year and didnt have any problems.
But, as i didnt get any feadback from other people, i'm not sure if
everything is correct.

Greetings
			Attila Kinali

--=20
Emacs ist f=FCr mich kein Editor. F=FCr mich ist das genau das gleiche, als=
 wenn
ich nach einem Fahrrad (f=FCr die Sonntagbr=F6tchen) frage und einen pangal=
aktischen
Raumkreuzer mit 10 km Gesamtl=E4nge bekomme. Ich wei=DF nicht, was ich dami=
t soll.
		-- Frank Klemm, de.comp.os.unix.discussion

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