Hi,
do we want to port the bio(4) interface and associated bioctl(8) tool
from openbsd ? Basically it allows control of hardware RAID controllers in a
generic way (get states, add hot-spare, start rebuilds, etc ...).
On OpenBSD it's currently supported on ami(4), arc(4), ciss(4), mfi(4).
I won't go into the softraid stuff, at last not yet.
Man pages:
http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/sbin/bioctl/bioctl.8?rev=1.43&content-type=text/plain
http://www.openbsd.org/cgi-bin/cvsweb/~checkout~/src/share/man/man4/bio.4?rev=1.19&content-type=text/plain

In kernel, there's a pseudo-device (bio) to which RAID controllers registers
(note that we can use the controllers without bio(4) in the kernel).
This pseudo-device keeps a list of raid controllers, and dispatch the
IOCTLs. This avoids having one major device per controller driver type.

OpenBSD has added sensors for the drives: SENSOR_DRIVE, with the states:
#define SENSOR_DRIVE_EMPTY    1
#define SENSOR_DRIVE_READY    2
#define SENSOR_DRIVE_POWERUP  3
#define SENSOR_DRIVE_ONLINE   4
#define SENSOR_DRIVE_IDLE     5
#define SENSOR_DRIVE_ACTIVE   6
#define SENSOR_DRIVE_REBUILD  7
#define SENSOR_DRIVE_POWERDOWN        8
#define SENSOR_DRIVE_FAIL     9
#define SENSOR_DRIVE_PFAIL    10
The benefit of this is that we could get notification in real time
instead of polling though bioctl.

I want this for mfi(4), for which I have no alternatives to get RAID status
(if a drive fail you don't know, unless you go in front of the box and look
at the LEDs). I will also add support to amr(4) as I have the hardware
for this.

Comments ?

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--