Subject: Re: 32 bit dev_t, Revision 2
To: Chris G. Demetriou <firstname.lastname@example.org>
From: Todd Vierling <tv@NetBSD.ORG>
Date: 01/11/1998 19:13:39
On Sun, 11 Jan 1998, Chris G. Demetriou wrote:
: There's no reason that you can't have thousands of LKM devices per
: kernel, _without_ devoting a bit to it.
: doing _anything_ other than a table is going to be slower than a
: table-based approach (though, compared to the work required to do a
: device access, that's not really significant). Using a solely
: table-based approach _does not_ prevent you from switching to using a
: bit mask later, does not prevent you from having thousands of LKM
: devices, etc.
: There's no need to do the bit-fiddling now, so why make one large
: change which introduces a whole lot of complexity, when there really
: is no reason that part of it couldn't be done later?
Well, one bit mask at the very least is a good thing: MI versus MD devices.
The former could be in a table in the MI part of the sys tree, and the
latter in tables in the various arch trees. This was my original thought
wrt bit masks, and I added the "dynamic" space after the fact.
I dunno, do we at least want to specify device number ranges for MI and MD
so we don't start using up device numbers for platform specific devices
starting at `1'? Seems kinda pointless to me to have a whole bunch of NULL
entries in `the table' for devices for other platforms.
===== Todd Vierling (Personal email@example.com) =====
== "There's a myth that there is a scarcity of justice to go around, so
== that if we extend justice to 'those people,' it will somehow erode the
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