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From: Wilko Bulte <wilko@yedi.iaf.nl>
Message-Id: <199609301943.UAA00673@yedi.iaf.nl>
Subject: Re: HP T4000s tape drive
To: joerg_wunsch@uriah.heep.sax.de
Date: Mon, 30 Sep 1996 20:43:58 +0100 (MET)
Cc: freebsd-scsi@FreeBSD.ORG, richard@cogsci.ed.ac.uk
In-Reply-To: <199609300625.IAA11367@uriah.heep.sax.de> from "J Wunsch" at Sep 30, 96 08:25:42 am
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As J Wunsch wrote...
> As Richard Tobin wrote:
> 
> > > > ! #define SCSI_2_MAX_DENSITY_CODE	0xff	/* SCSI 2 spec is out of date! */
> > > and this?  The entire check for a ``max density'' could go.
> > 
> > Well the user passes it in as a u_int32 (in the ioctl) and it gets
> > assigned to a u_char (for the scsi_select), so perhaps a range check
> > is still appropriate?
> 
> No.  It's garbage.  There's no use of limiting the density range that
> could be passed down to the device.  The worst that happens (if a user
> specifies a bogus density in the ``mt density'' command) is a SCSI
> error that will pop up on the console.  We already agreed before that
> this test can go away.

As an example: my DLT2000 can use 0x81 to switch to compressed mode.
Drives should be smart enough to return invalid mode or something similar.

Wilko
_     ____________________________________________________________________
 |   / o / /  _  Bulte  email: wilko@yedi.iaf.nl - Arnhem, The Netherlands
 |/|/ / / /( (_) 	Do, or do not. There is no 'try' - Yoda
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