Re: Serial Attached SCSI Driver Interface (SDI)

[Jeff Garzik <jgarzik@pobox.com>]

Luben Tuikov wrote:
> I completely agree with you.  Minimalistic approach is a good thing.
> 
> As to the API: the more reason for knowlegable Linux folks to keep
> an "eye" on SDI and other relevant developing standards.
> This way there'd be yet another voice of experience (Linux).
> 
> Getting the design right is very important.  IMO, I think it'd
> better to have OS independence (SDI) as opposed to "Windows, Linux
> and other OSs are addressed" (pre-SDI).

I would prefer to see how a rough-draft Linux implementation would look 
first.  Otherwise, without an implementation, linux-scsi denizens don't 
really have a basis from which to form design input.  That's really the 
"Internet way" -- form a rough consensus based on [test | production] 
implementations, then write the standard.

This area is also a bit delicate politically, because various companies 
have various bits of "value-add" in their management utils.  This is 
delicate because it clashes with the Linux wish to be vendor-neutral.  A 
vendor-neutral "Linux-ish" management API (be it RAID or SAN or 
whatever) would strongly encourage existence of a vendor-neutral, open 
source management utility.


For a starting point...  basically the problem boils to:  you need a 
control point (/dev node, /sysfs file, ioctl, etc.) that allows you to 
create, destroy, and manipulate nodes [a.k.a. SCSI targets] and node 
attributes.  James seemed to favor creating a few transport classes 
(visible through sysfs) that could act as these control points.

I should dig up a RAID card somewhere, and see what I could do about a 
block-level RAID management API.  (thinking out loud, probably silly)

	Jeff