RE: iSCSI Change - New NOP-Out/In text

["Wheat, Stephen R" <stephen.r.wheat@intel.com>]

Here is a (maybe partial) draft of the suggested NOP-In rewording.  Whether
this type of commentary is worthwhile, please let me know.

Embedded are some questions I have from the original writing this morning.

As a commentary/question, shouldn't all fields be documented, rather than
having their semantics covered in other field documentation???

At the very least, I'd appreciate the text to be changed to answer my
questions embedded below.

BTW, since a NOP-In could result in a corresponding NOP-Out, the name of the
ping data fields is kind of lopsided.  I.e., for NOP-Out, it is "Ping Data",
and for NOP-In, it is "Return Ping Data."  A NOP-Out's ping data is "return
ping data" when sent as a response to a NOP-In.  So, how about just calling
it "Ping Data" in both messages??

Stephen

==================

1.2  NOP-In

   NOP-In is either sent by a target as a response to having received a
NOP-Out,
   as a "ping" to an initiator, or a means to carry a changed ExpCmdSN
   and/or MaxCmdSN if there is no other PDU to carry them for a long time.

   When a target receives the NOP-Out with a valid Initiator Task Tag (not
   the reserved value 0xffffffff), it MUST respond with a NOP-In with the
   same Initiator Task Tag that was provided in the NOP-Out Command. It
   SHOULD also duplicate up to first 4096 bytes of the initiator provided
   Ping Data.

1.2.1     Target Transfer Tag

   A target assigned identifier for the operation.

   If the target is responding to a NOP-Out, this is set to ?????????

   If the target is initiating a NOP-Out as a Ping (intending to receive a
corresponding
   NOP-Out), this field is set to a valid value (not the reserved
0xffffffff).

   If the target is initiating a NOP-Out without wanting to receive a
corresponding
   NOP-In, this field MUST hold the reserved value of 0xffffffff.

1.2.2   Initiator Task Tag
   When the NOP-Out is in response to a NOP-In, this is the same value as
found in the NOP-Out.

   Otherwise, this field MUST be 0xffffffff.

1.2.3     LUN

   A LUN MUST be set to a correct value when the Target Transfer Tag is
   valid (not the reserved value 0xffffffff).  Otherwise, it SHOULD be set
to the
   reserved value of 0.

1.2.4  StatSN
   Whenever the NOP-In is not issued in response to a NOP-Out the, StatSN
   field will contain the next StatSN but StatSN for this
   connection is not advanced.  Otherwise, it will be set to ????????.

1.2.5  Data Segment Length
   The number of bytes in the Return Ping Data.  The range is [0..4096].