recent commits and availability

[Alex Hornung]

Hi all,

first off I'd like to mention that the best way to contact me from now
on isn't IRC anymore but rather e-mail. This is because I wast^Wspend
way too much time on IRC, so I'm cutting back on that. So please drop me
an email if something is wrong with a commit, or for
comments/reviews/asking for reviews/criticism/...

Regarding the recent commits to switch device mapper over to our disk
subsystem, please note that I'm not quite done yet. There are a few
quirks and issues such as the creation of the compatbility slice s0
(/dev/mapper/foo.s0) and some issues with the base device
(/dev/mapper/foo) that doesn't allow it to be used for at least swap,
but possibly also others. I'll fix that as soon as I can, probably some
time this week.

In one of the commits I've switched hotplugd to use libdevattr which
means that the hotplug(4) device driver should be ripped out of the
kernel. I'd appreciate if someone could do that; it's just a matter of
deleting the files and removing the lines from sys/conf/files (?) and
the Makefile in sys/dev/misc (?).

I've also bound dm into devstat, which means it will show up on iostat,
but due to the formatting used by iostat, it means you will just see
'mapper0' or so instead of 'mapper/foo'.

Kind Regards,
Alex Hornung