We could add a new event type (EVFILT_DEVICE (?)) and add support into
	various device layers to raise this event. I have no objection to
	doing this; it makes perfect sense to me.

	I think the reason why jlemon classified it as generic was that:
	a) it already supports a bunch of different type of events, and
	b) it's fairly simple to add new event types, even if currently it
	   requires adding new types to <sys/event.h>. I have thoughts
	   about how to make this easier for dynamic event addition
	   (e.g., for lkm's); they need to be fleshed out a bit more first.

	I don't think it would be appropriate to hold back incorporation
	of this work because it does have every event time that anyone can
	think of right now.

I think that needing to add new event types to <sys/event.h> is
a problem.  The issue is not being able to handle every event that
anyone can think of but being able to add events without fears of
conflicts.  Since the interface is exported to userland, we shouldn't
need to recompile the universe because someone added a new event type.
I'm afraid that this limitation will eventually require the interface
be replaced by something more flexible, so I really would like to
have that issue addressed first.

Eduardo