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From: Charles Henrich <henrich@crh.cl.msu.edu>
Message-Id: <199701052032.PAA03705@crh.cl.msu.edu>
Subject: Re: more than 32 disks?
To: dg@root.com
Date: Sun, 5 Jan 1997 15:32:35 -0500 (EST)
Cc: freebsd-hackers@freebsd.org
In-Reply-To: <199701030329.TAA18783@root.com> from David Greenman at "Jan 2, 97 07:29:46 pm"
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> unit number. This means that one will have to make driver changes to go
> beyond 32 units. :-(

I noticed this pop up in relation to CD changers as well.  I have a suggestion,
perhaps I'll even get a moment to write it (assuming people think this is a
good idea).  During boot phase when DEVFS is probing around making devices,
change the format of the minor number to just be 11 bits for type, and then 21
bits as an offset into a dynamically built kernel table (4 bytes/entry).  This
gives us 2097152 different device possibilities.. Still a limit (I hate limits)
but far better than what we have today!

-Crh

       Charles Henrich     Michigan State University     henrich@msu.edu

                         http://pilot.msu.edu/~henrich