multi-vkd support patch for review

[Chris Turner]

Sascha Wildner wrote:
> I've cleaned it up a bit and added some words to the man page. Please
> check out http://leaf.dragonflybsd.org/~swildner/multivkd.diff
Nifty - I was thinking of pestering the lists to check on it -
because I just *know* someone had to be using it, especially with
all this new-fangled-filesystem-talk :)
> Can you cvsup and try again? This was due to a bug in get_empty_drive().

will do - although my -CURRENT machines are unavailable at the moment,
so I'll probably manually apply to 1.8 release until a week or so from
now.
Another thing to be noted was that vinum assumes it's using a kernel
module generally, and the vinum docs warn against a static build,
and I had to statically built into the VKERNEL since module support for 
vkernels isn't? there yet?...

> Well, regardless of the vinum issue, I think what we already have is
> useful enough to be committed.
thanks & IMHO agree

> The only thing I'm wondering about is if we should rename the '-r'
> option to the more general '-D' (analogous to -I). Any opinions on this?
personally I wasn't sure what to use, as '-r' didn't seem to fit,
so -D works and makes more sense (to me) as well.
I'm probably going to look at various command line / config file kinds 
of things for the vkernel 'CLI' if you call it that in about a month or 
so - right now I'm working on getting my systems installed in a very 
repeatable way for some performance & stress tests I want to do shortly.

> I'll commit the patch next weekend if no one objects.

woohoo! thanks!

- Chris