Re: [PATCH 21/24][RFC] scsi_tgt: use of sense accessors

[Pete Wyckoff <pw@osc.edu>]

bharrosh@panasas.com wrote on Mon, 04 Feb 2008 19:53 +0200:
>   FIXME: I need help with this driver (Pete?)
>     I used scsi_sense() in a none const way. But since
>     scsi_tgt is the ULD here, it can just access it's own sense
>     buffer directly. I did not use scsi_eh_cpy_sense() because
>     I did not want the extra copy. Pete will want to use a 260
>     bytes buffer here.
> 
> Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
> Need-help-from: Pete Wyckoff <pw@osc.edu>

FYI, I never use scsi_tgt.  Only just pure userspace on the target,
and a dumb ethernet NIC that does not know it is speaking any form
of SCSI.

People who need scsi_tgt have real target-enabled NICs like the
fancy qla4xxx.  Those act as SCSI targets across FC or IP or
whatever and bring commands into the kernel, which then relays them
to a userspace tgtd process, which does the read/write as necessary,
and returns a result code to the NIC to ship back across FC.

So sorry, I won't take a guess at what has to happen here.  But
yeah, you are right that an OSD target implementation would at times
need a sense buffer bigger than 96.  Protocol maximum length for all
sense data is 264.

		-- Pete