NAME       : HCPMTPBK
 DESCRIPTION: MEMBER TOPOLOGY PACKET
              This copy file contains:
              MTPBK DSECT which maps a Member Topology Packet (MTP)
              MTRTABLE MACRO that is used to define the synchronization
              request router table
              MTRTABL DSECT which maps a router table entry
 DSECT      : MTPBK
 FUNCTION   : Used to transmit Relocation Domain topology to other members
              of the SSI. The MTPBK is used in four circumstances:
              1) To propagate a DEFINE DOMAIN request from the member that
              receives the user's command to other members of the SSI.
              2) To propagate notification of a concurrent upgrade to
              members of the SSI.
              3) For resynchronization purposes when a member rejoins the
              SSI following a transition out of safe mode.
              4) For synchronization purposes when a member first joins the
              SSI cluster.
              Each of these four uses requires different processing on the
              receiving system. Therefore a router worker ID is included in
              the MTP to allow the receiving thread to route the MTP
              correctly.
              Router table entries comprise the worker routine address
              with a flag to indicate whether they are invoked synchronously
              or asynchronously using a deferred call.
              Synchronous calls return an MTP from the receive in the
              SEND_REPLY message.
              Asynchronous calls return a SEND_REPLY VOTE=YES as soon as
              the worker has been scheduled.  No MTP response is sent back.
              The worker routines are responsible for freeing their input
              MTP.
 LOCATED BY : In the message buffer portion of an MBHBK
 CREATED BY : HCPRDMBT
 DELETED BY : Synchronization worker routines once they are
              finished their work.
 SERIALIZED : The VAAXLK will be held during processing that uses MTPBKs.
 RELOCATION CONSIDERATIONS : None

 MTPBK DSECT
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Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      MTPBK          MEMBER TOPOLOGY PACKET
0000    0 Signed       4 MTPLEN         Length of MTPBK in bytes
0004    4 Signed       4 MTPSNDX        Sending member's index
0008    8 Signed       4 MTPCVN         Comms Version for domain sync
                                        operations MTPCVN is used to
                                        identify the communications
                                        protocol version used by
                                        cross-SSI Domain and ARD
                                        synchronization. The VAACVN is
                                        stored in the Member Topology
                                        Packet in MTPCVN to alert a
                                        remote member of the version of
                                        the comms structures and
                                        protocols in use by the CP.
      When a MTPBK is created MTPCVN is populated with MTPCVER.
          00000001       MTPCV1         1 Comms Version 1
          00000002       MTPCV2         2 Comms Version 2
          00000003       MTPCV3         3 Comms Version 3
          00000004       MTPCV4         4 Comms Version 4
          00000005       MTPCV5         5 Comms Version 5
          00000006       MTPCV6         6 Comms Version 6
          00000007       MTPCV7         7 Comms Version 7
          00000008       MTPCV8         8 Comms Version 8
          00000009       MTPCV9         9 Comms Version 9
          00000001       MTPCVER        MTPCV1 Comms Version supported by
                                        this CP
000C   12 Signed       4 MTPRID         Router Worker Id (or Request ID)
0010   16 Signed       4 MTPSEQ         State sequence number for this
                                        request. For synchronization
                                        requets this will be set to the
                                        sender's VAASEQ. For new DEF RELO
                                        requets this will be set to the
                                        sender's next state (VAASEQN)
0014   20 Signed       4 MTPDCT         Number of Domain Entries in
                                        Packet
0018   24 Bitstring    1 MTPFLAGS       Flags for the message
          1... ....      MTPGLOCK       X'80' MTPGLOCK Indicates that the
                                        requester has acquired the VAAXLK
                                        lock globally. If this bit is
                                        OFF, the receiver(s) of this
                                        packet must get the lock locally
                                        before doing the necessary
                                        processing. If it is ON, the
                                        receiver must call HCPXLKUU to
                                        inform the lock manager it will
                                        release the lock.
0019   25 Bitstring    3 *              Reserved for future IBM use
001C   28 Signed       4 MTPXLUNQ       Value of XLKUNQ after the global
                                        lock was obtained. This is passed
                                        to the remote system which then
                                        passes it to HCPXLKUU to register
                                        that the remote worker routine is
                                        now responsible for releasing the
                                        lock on that system
          00000020       MTPHLEN        *-MTPBK MTP Header length The
                                        rest of the MTPBK is variable
                                        length depending on the number of
                                        domains in the member's topology.
                                        There is one MTPENT for each
                                        domain in the member's topology.
                                        They are appended here as an
                                        array of MTPENTs one after the
                                        other. MTPDCT contains the count
                                        of entries appended in the
                                        packet.
0020   32 Bitstring   12 MTPENT         Domain Entry
0020   32 Character    8 MTPDNM         Domain Name
0028   40 Bitstring    4 MTPDMM         Domain Membership Mask. Zero mask
                                        signals domain deletion.
          0000000C       MTPENTL        L'MTPENT Length of a domain entry
                                        (bytes)
          00000004       MTPHDDWL       (MTPHLEN+7)/8 Length of an MTP
                                        header (DWs)
      Mapping DSECT for the MTP Router Table

          
*** MTPBK - MEMBER TOPOLOGY PACKET
*
*     +---------------------------+---------------------------+
*   0 |          MTPLEN           |         MTPSNDX           |
*     +---------------------------+---------------------------+
*   8 |          MTPCVN           |          MTPRID           |
*     +---------------------------+---------------------------+
*  10 |          MTPSEQ           |          MTPDCT           |
*     +------+--------------------+---------------------------+
*  18 |:FLAGS|////////////////////|         MTPXLUNQ          |
*     +------+--------------------+---------------------------+
*  20 |                        MTPENT                         |
*     |                           +---------------------------+
*     |                           | 2C
*     +---------------------------+
*
*** MTPBK - MEMBER TOPOLOGY PACKET
          
*** Overlay for MTPENT in MTPBK
*
*     +-------------------------------------------------------+
*  20 |                        MTPDNM                         |
*     +---------------------------+---------------------------+
*  28 |          MTPDMM           | 2C
*     +---------------------------+
*
*** Overlay for MTPENT in MTPBK

 
Symbol         Dspl Value
-------------- ---- -----
MTPCVER        0008 00000001
MTPCVN         0008
MTPCV1         0008 00000001
MTPCV2         0008 00000002
MTPCV3         0008 00000003
MTPCV4         0008 00000004
MTPCV5         0008 00000005
MTPCV6         0008 00000006
MTPCV7         0008 00000007
MTPCV8         0008 00000008
MTPCV9         0008 00000009
MTPDCT         0014
MTPDMM         0028
MTPDNM         0020
MTPENT         0020
MTPENTL        0028 0000000C
MTPFLAGS       0018
MTPGLOCK       0018 80
MTPHDDWL       0028 00000004
MTPHLEN        001C 00000020
MTPLEN         0000
MTPRID         000C
MTPSEQ         0010
MTPSNDX        0004
MTPXLUNQ       001C