smp_utils: command line utilities for SAS expanders

[Douglas Gilbert]

On 11-09-08 10:49 AM, Kenneth D. Merry wrote:
> On Wed, Sep 07, 2011 at 11:19:59 -0700, Matthew Jacob wrote:
>>
>>> It'll get fixed when we add SMP probe code into CAM.
>>
>> ETA?
>
> Last year I would have said this year.  Right now I'm not sure.
>
> It'll probably happen along with the multipathing work we're planning to do
> for CAM, since our initial goal will be handling multiple paths in a SAS
> topology.
>
> Our management is currently figuring out our priorties for the next set of
> features they want.  Once they figure that out I may have a better idea of
> when it'll happen.  I'm pretty sure multipathing won't be the next feature
> we do, so my guess is that we wouldn't start on it until next year.
>
> If there are other folks who are interested in helping out so that the
> multipathing work happens sooner, that might influence our time frame for
> working on it to some extent.
>
> One short-term note -- I'm working on support for descriptor sense right
> now.  Seagate's new 3TB SAS drives return descriptor sense by default.

If you are working on sense data then you might find the
sg_decode_sense utility in the sg3_utils package useful.
[BTW I have ported most of my packages to FreeBSD:
sg3_utils, sdparm, smp_utils and ddpt.] Also the
sg_lib_data.c file in the sg3_utils' lib directory contains
an up to date list (in C) of asc/ascq strings.


And then there is this nasty slipped into SAM-5 (sam5r07.pdf
section 5.3.1): "Sense data may be delivered in the buffer
defined by the Sense Data argument of the Execute Command
procedure call (see 5.1) for ANY status code."
The only example of this so far seems to be referrals (see
sbc3r27.pdf section 4.26.4). Now a successful SCSI READ may
return status=GOOD with sense data that contains
sense_key=COMPLETED and the asc/ascq pair for "INSPECT
REFERRALS SENSE DESCRIPTORS". I don't think Linux is even
close to handling this new wrinkle.

Doug Gilbert