Subject: Re: 32 bit dev_t, Revision 2
To: None <>
From: Darren Reed <>
List: tech-kern
Date: 01/12/1998 13:08:10
In some mail I received from Perry E. Metzger, sie wrote
> Todd Vierling writes:
> > On Mon, 12 Jan 1998, Darren Reed wrote:
> > 
> > : I assume for %10 and %11 there will need to be a registry kept, no ?
> > 
> > Yes, there would be a registry.  We already have one, for our current device
> > setup, but it is completely port-dependent.
> > My idea in thinking this was that for now, all devices could have static
> > numbers, but sometime in the (near?) future, devices would become dropped
> > into the dynamic pool even if compiled directly into the kernel (devfs
> > style).
> Well, that isn't in the current projects list... and even if it were,
> real machines don't have 2000 devices on the bus.

But what about 2000 different vendors each with their own devsw ?  You
want any combination of those 2000 to work.

Point I was trying to make is that if the divers for everything except
(say) wd/sd/xd/fd/tty/pty devices use dynamic major number allocation,
you only need 1 table (or 2 if cdevsw & bdevsw remain separate).

You also do away with the need to "reserve bits for MD and MI" drivers
and none of the 2k for this, 1k for that, etc.

Sure it is more complex, but things like add_drv/rem_drv on Solaris
are *damn nice* and only need to be run once.