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Prolog 
Control Block Contents 
   PODBK DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.


  PODBK Prolog Top of page
 
 NAME       : HCPPODBK
 DESCRIPTION: Relocation Pages on DASD Block
 DSECT      : PODBK
 FUNCTION   : A Relocation Pages on DASD block will hold information
              about the pages from DASD that will be sent from the
              source to the destination during relocation.
 LOCATED BY : PODBKs are queued in a gated queue that is anchored
              at RLOBK.RLOPODGQ. Each relocation will have a separate
              gated queue.  The first two fullwords of the gated
              queue field point to the first and last WORKITEM
              (HCPPODBK).
 CREATED BY : A Relocation Pages on DASD block is allocated by
              HCPPODNQ and HCPPODPW in HCPPOD.
 DELETED BY : A Relocation Pages on DASD block is released by
              HCPPODDQ and/or HCPPODSQ in HCPPOD.
 REFERENCES : See HCPPOD for information about the usage of this
              block.
              See HCPPOD for information about the role that this
              block plays in PGMBK Walker (HCPRLTPW) throttling.
 SERIALIZED : The queueing and dequeing of PODBKs are serialized by
              the gated queue macro (HCPGQMGR).
 RELOCATION CONSIDERATIONS : - This block is not relocated during a relocation of a
              guest from one system to another.
              - During a relocation, one PODBK is created for each
              guest page that is on DASD and needs to be sent to
              the destination system.
 NOTES      : There are two flavors of HCPPODBKs.
              1.- Contains a PTE from a page on DASD that
              relocation needs to send.
              2.- Contains a Post-And-Wait message to notify
              HCPPODDQ that the complete address space was
              processed for the current relocation memory
              pass.
              DSECT USED AS WORKING ELEMENT FOR THE GATED QUEUE MANAGER
              (If FLAG not set, then PODBK is defined as follows)
              +------+------+------+------+------+------+------+------+
              | NEXT ELEMT IN GATED QUEUE | FLAG |  RESERVED FOR IBM  |
              +------+------+------+------+------+------+------+------+
              |                  PTE FOR PAGE ON DASD                 |
              +------+------+------+------+------+------+------+------+
              |    ADDRESS OF THE RLOBK   |      RESERVED FOR IBM     |
              +------+------+------+------+------+------+------+------+
              (If FLAG is set to PODNOTIFY, then PODBK is defined as
              follows)
              +------+------+------+------+------+------+------+------+
              | NEXT ELEM IN GATED QUEUE  | FLAG |  RESERVED FOR IBM  |
              +------+------+------+------+------+------+------+------+
              |   RESERVED FOR IBM USE    | CPEBK TASK FOR POST & WAIT|
              +------+------+------+------+------+------+------+------+
              |    ADDRESS OF THE RLOBK   |      RESERVED FOR IBM     |
              +------+------+------+------+------+------+------+------+
 
 
  PODBK Control Block Content Top of page
 

 PODBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure PODBK Relocation Pages on DASD Block 0000 0 Address 4 PODNEXT Reserved for Gated Queue Manager for use as a queue chain pointer 0004 4 Bitstring 1 PODFLAG Work element flag 00000080 PODNOTIFY X'80' PODNOTIFY This work element is for notification processing. >>>> BEGIN DEBUG ONLY CODE <<<< This debug only code is taking part of the reserved space. >>>> END DEBUG ONLY CODE <<<< 0005 5 Bitstring 1 * (3) Reserved for future IBM use. 0008 8 Address 8 PODPTE PTE for page on DASD. 0010 16 Address 4 PODRLO Address of the RLOBK related to this PTE 0014 20 Address 4 PODPWI Address of PWIBK 00000003 PODDSIZE ((*-PODBK)+7)/8 PODBK size in double-words 00000018 PODBSIZE PODDSIZE*8 size in bytes 0008 8 Address 4 * Reserved for future IBM use. 000C 12 Address 4 PODPOST CPEBK address to stack when this work element is processed.
 
 
  PODBK Storage Layout Top of page
 
          
*** PODBK - Relocation Pages on DASD Block
*
*     +---------------------------+------+--------------------+
*   0 |         PODNEXT           |:FLAG |////////////////////|
*     +---------------------------+------+--------------------+
*   8 |                        PODPTE                         |
*     +---------------------------+---------------------------+
*  10 |          PODRLO           |          PODPWI           |
*     +---------------------------+---------------------------+
*  18
*
*** PODBK - Relocation Pages on DASD Block
          
*** Overlay for PODPTE in PODBK
*
*     +---------------------------+---------------------------+
*   8 |///////////////////////////|         PODPOST           |
*     +---------------------------+---------------------------+
*  10
*
*** Overlay for PODPTE in PODBK
 
 
  PODBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
PODBSIZE       0014 00000018
PODDSIZE       0014 00000003
PODFLAG        0004
PODNEXT        0000
PODNOTIFY      0004 00000080
PODPOST        000C
PODPTE         0008
PODPWI         0014
PODRLO         0010
 
This information is based on z/VM 7.1.0 Last updated on 22 Jun 2018 at 11:51:32 EDT.
Copyright IBM Corporation, 1990, 2018