Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.

SSQBK

Prolog  

Control Block Contents  
   SSQBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


SSQBK Prolog

 Name       : HCPSSQBK
 DESCRIPTION: SPXTAPE Section Quorum Block
 DSECT      : SSQBK
 FUNCTION   : Work area to hold the data page
              system virtual addresses for one
              allotment of read buffers.
 Located by :
              Routines:
              HCPSPXDR - read file and save ASA's
              HCPSPYTM - lock vpages and build channel program
              HCPSPXTI - unlock vpages and return count to pool
              Control block fields:
              TKTSSQ   - head of queue in the TKTBK
              SSQNEXT  - next in queue
 Created by : HCPSPXDU - for SPXTAPE DUMP commands
              HCPSPZRI - for SPXTAPE LOAD commands
 Deleted by : HCPSPORR - for SPXTAPE DUMP commands
              HCPSPOFV - for SPXTAPE DUMP commands
              HCPSPNDW - for SPXTAPE LOAD commands

 

SSQBK Control Block Content


SSQBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      SSQBK          SPXTAPE Section Quorum Block
0000    0 Signed       4 SSQNEXT        Next work area
0004    4 Bitstring    1 SSQFLAG        Flags for this quorum
          ..1. ....      SSQTAKEN       X'20' SSQBK selected for output
                                        processing
          .... 1...      SSQEOF         X'08' End of file with this block
          .... .1..      SSQREADY       X'04' Reads complete for this
                                        quorum (has VAs or 0s) Does not
                                        contain any ASAs
          .... ...1      SSQERROR       X'01' Read errors detected
0005    5 Bitstring    1 * (3)          Reserved
0008    8 Signed       4 SSQPAGCT       Count of data pages in section
000C   12 Signed       4 SSQPAGNO       File relative page number of
                                        first page
0010   16 Signed       4 SSQCMCUR       Last committed current slot.
                                        Point of back out in case of I/O
                                        error.
0014   20 Signed       4 SSQCUR         Current slot
0018   24 Signed       4 SSQEND         Address past last slot
001C   28 Signed       4 SSQDASWT       Waiting CPEBK when DASD I/O done
0020   32 Signed       4 SSQWTCNT       Count of DASD tasks to end wait
0024   36 Signed       4 SSQVPGS (32)   Slots for this group of pages
          00000080       SSQVPLEN       *-SSQVPGS Size of the page list
                                        area
          00000020       SSQALLOT       SSQVPLEN/4 Standard quorum
                                        allotment count
          00000015       SSQDWLEN       (*-SSQBK+7)/8 Size in double
                                        words

 

SSQBK Storage Layout

          
*** SSQBK - SPXTAPE Section Quorum Block
*
*     +---------------------------+------+--------------------+
*   0 |         SSQNEXT           |:FLAG |////////////////////|
*     +---------------------------+------+--------------------+
*   8 |         SSQPAGCT          |         SSQPAGNO          |
*     +---------------------------+---------------------------+
*  10 |         SSQCMCUR          |          SSQCUR           |
*     +---------------------------+---------------------------+
*  18 |          SSQEND           |         SSQDASWT          |
*     +---------------------------+---------------------------+
*  20 |         SSQWTCNT          |                           |
*     +---------------------------+                           |
*  28 |                                                       |
*     =                       SSQVPGS                         =
*     |                           +---------------------------+
*     |                           | A4
*     +---------------------------+
*
*** SSQBK - SPXTAPE Section Quorum Block

 

SSQBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
SSQALLOT       0024 00000020
SSQCMCUR       0010
SSQCUR         0014
SSQDASWT       001C
SSQDWLEN       0024 00000015
SSQEND         0018
SSQEOF         0004 08
SSQERROR       0004 01
SSQFLAG        0004
SSQNEXT        0000
SSQPAGCT       0008
SSQPAGNO       000C
SSQREADY       0004 04
SSQTAKEN       0004 20
SSQVPGS        0024
SSQVPLEN       0024 00000080
SSQWTCNT       0020

This information is based on z/VM V4R2.0. Last updated on 17 Oct 2001 at 16:59:22 EDT.
Copyright IBM Corporation, 1990, 2001