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From: trt@rti.rti.org (Thomas Truscott)
Newsgroups: comp.unix.large
Subject: How does one add a custom device driver to an Amdahl kernel?
Message-ID: <4079@rtifs1.UUCP>
Date: 17 Sep 90 21:54:36 GMT
References: <PAR.90Sep10154010@hq.af.mil> <98J602sDc85K01@amdahl.uts.amdahl.com>
Organization: Research Triangle Institute, RTP, NC
Lines: 26


We sell a distributed file/computing system (Freedomnet)
that is added to the kernel as a "pseudo device driver".

Unfortunately, Amdahl does not provide any way to add
a custom (i.e. unknown to Amdahl) device driver.
Here are some specific problems:

1) Running "sysgen" creates a completely new conf.c file
(containing bdevsw and cdevsw) from /etc/devlist (as I recall).
We cannot add our device to devlist,
but manually editing conf.c is futile because the next time
sysgen is run our changes disappear.

2) The /dev directory is completely regenerated by sysgen.
That means our "/dev/FN" entry disappears on each sysgen.

3) The major device numbers are dynamically assigned
on each sysgen.  (Minor detail, it just makes our task
a little harder.)

We do have hacks to /etc/sysgen and uts/cf/cf.mk,
but the result is less than ideal.
Is there something we have overlooked?
	Tom Truscott
	(919) 541-7005