iSCSI: v15 R2T and DATA-OUT

["Rod Harrison" <rod.harrison@windriver.com>]

Folks,

	There is a potential inconsistency in the description of the use of
the LUN field in DATA-OUT and R2T in the working v15 draft.

	9.7.3 Target Transfer Tag, for DATA-IN last paragraph says ...

	"If the Target Transfer Tag is provided, then the LUN field MUST hold
a valid value and be consistent with whatever was specified with the
command;"

	9.8.5 Target Transfer Tag, for R2T says ...

	"The Target Transfer Tag and LUN are copied in the outgoing data PDUs
and are used by the target only."

	Potentially a target could return a different LUN field in the R2T,
for perhaps some funky LUN mapping or other internal reason expecting
it to be copied to the DATA-OUT as per the R2T text. I suspect we just
want to say this is not allowed and the LUN field MUST be the same as
the command PDU.

	Either way I think we need to indicate what is expected of the
initiator if the LUN field in the R2T does not match the LUN in the
command PDU.

	Apologies for not spotting this before the end of last call.

	- Rod