MFC: graid(8) (RAID GEOM) support

[Doug Ambrisko]

Jeremy Chadwick writes:
| Sorry for the cross-post, but I thought both lists would want to know
| about this.
| 
| Looks like mav@ just committed this ~17 hours ago:
| http://www.freebsd.org/cgi/cvsweb.cgi/src/sys/geom/raid/g_raid.c
| 
| Those who have historically wanted to use Intel MatrixRAID (now called
| Intel RST (Rapid Storage Technology)), but haven't due to the severe
| issues/risks with ataraid(4), will probably be very interested in
| this commit.  I know I am!
| 
| I plan on stress-testing the Intel support on a 2-disk system with
| RAID-1 enabled, and will document my experiences, procedures, etc...

We definitely want people to help test this out.  It was designed from 
the start to be robust and do recovery for RAID 1 which is our use.
We had previously hacked enhanced support into ataraid(4) and ata(4) for 
use in-house. 

Doug A.