AoE & driver tips

[sah at coraid.com]

Hello,

I'm in the process of writing a AoE disk/protocol driver for freebsd.
AoE (ATA over Ethernet) is used to access ATA devices attached directly to the Ethernet using the AoE registered Ethernet protocol type 0x88a2.  I have already written a driver for linux 2.4 and 2.6 that makes AoE devices show up as local disks.  I'm hoping to do the same for freebsd.  I have some questions from my
initial perusal of the code.

I've been looking at the code in sys/dev/ata/ for tips on plugging into the disk device layer.
It appears that what I want is disk_create && disk_destroy.  How is the parameter "unit" related
to device major & minor?  I don't see anywhere where major and minor are related to the disk
structure, though perhaps I'm just missing it.  Do I need to register a device major?

If a device fails or vanishes, can i just fail the outstanding bios and disk_destroy it?

How does freebsd do SMART on ata?  I'd like to be able to plug into this as well
if the system uses it.

Any other tips/comments about gluing together the disk & network would be appreciated.

Cheers,

Sam
sah at coraid.com