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

CHPBK

Prolog  

Control Block Contents  
   CHPBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


CHPBK Prolog

 NAME       : HCPCHPBK
 DESCRIPTION: SPXTAPE Channel Program Block
 COPYRIGHT -  THIS MODULE IS "RESTRICTED MATERIALS OF IBM"
              5654-030 (C) COPYRIGHT IBM CORP. - 1994, 1998
              LICENSED MATERIALS - PROPERTY OF IBM
 DSECT      : CHPBK
 FUNCTION   : Work area to hold a channel program and
              the resources needed (including an
              IORBK) to issue an SPXTAPE tape I/O
              request and handle the completion or
              recovery procedures.
 LOCATED BY :
              Routines:
              HCPSPYWT - to set up the I/O operation
              HCPSPYWI - interrupt processing
              HCPSPZRT - to set up the I/O operation
              HCPSPZRI - interrupt processing
              Control block fields:
              TAPCHPQ  - head of queue in the TAPBK
              CHPNEXT  - next in circular queue
 CREATED BY : HCPSPYWT - SPXTAPE DUMP commands
              HCPSPZRT - SPXTAPE LOAD and SCAN commands
 DELETED BY : HCPSPYWT - SPXTAPE DUMP commands
              HCPSPZRT - SPXTAPE LOAD and SCAN commands
 References : HCPCHPBK requires HCPIORBK COPY

 

CHPBK Control Block Content


CHPBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      CHPBK          SPXTAPE Channel Program Block
     Reserve space for the base IORBK
0000    0 Dbl-Word     8 CHPIORBK (45)  Base IORBK region
     Lock for this IORBK and CHPBK work area
0168  360 Dbl-Word     8 CHPLOCK (3)    Lock to serialize this block
     Commit and recovery control data. Last items in the current block used
     to update commit cursors when successfully sent to tape.
0180  384 Signed       2 CHPCMCLR (0)   Beginning of area to be cleared
                                        before reuse for trailer
0180  384 Address      4 CHPCURTK       Last ticket contained in current
                                        block
0184  388 Address      4 CHPCMSSQ       Last SSQBK
0188  392 Address      4 CHPCMCUR       Address of next Vpage slot in
                                        last SSQBK
018C  396 Signed       4 CHPCURHD       Displacement in header of cur hdr
0190  400 Signed       4 CHPCMXAB       Amt of XAB data associated with
                                        last tkt remaining to be written
0194  404 Address      4 CHPLSTCW       CCW address of the last piece of
                                        data for files that completed in
                                        the current block. If = 0 then
                                        block contains no complete files
0198  408 Signed       4 CHPLLPTR       Last offset in page list +1 used
019C  412 Address      4 CHPLSTHD       Hdr addr for last completed file
01A0  416 Signed       4 CHPLBLKZ       Save last block size at last
                                        complete file/tkt in this block.
     Counters, etc.
01A4  420 Character   16 CHPTKTS        Queue of files completed in this
                                        channel program. Moved to TAPTKTQ
                                        when I/O completes OK.
                                        Single-threaded double-headed
                                        FIFO queue terminated by zero
01A4  420 Address      4 CHPTKTSH       Head of CHPTKTS
01A8  424 Address      4 CHPTKTST       Tail of CHPTKTS
01AC  428 Signed       4 CHPTKTCT       Corresponding count of files on
                                        CHPTKTS
01B0  432 Signed       4 *              Reserved
01B4  436 Signed       4 CHPENTRY       Current entry in the header
01B8  440 Signed       4 CHPLIMIT       After the last entry in the hdr
01BC  444 Signed       4 CHPLINDX       Index into CCW list of buffers
01C0  448 Signed       4 CHPOFFST       Offset into block where data
                                        should be added
01C4  452 Signed       4 *
01C8  456 Signed       4 CHPPOOLC       Count of pool pages (data pages)
01CC  460 Address      4 CHPPLIST (14)  List of pages locked for this blk
          00000038       CHPPLLEN       *-CHPPLIST Length to clear
          0000000E       CHPPLMAX       14 Maximum number of entries
0204  516 Signed       4 *              End flag for PLIST - zero = end
          00000088       CHPCMCRL       *-CHPCMCLR Length of area to be
                                        cleared before reuse for trailer
     Queue of CHPbks link field
0208  520 Address      4 CHPNEXT        Next work area in circular queue
     Save area across GOTO I/O request
020C  524 Signed       4 CHPSAVE (7)    Save R3-R9 across call to IOS.QS
     Channel Program and Header Block copied from TAPBK
0228  552 Dbl-Word     8 CHPPGM (26)    Modeset + hdr + 3*8 (desc + xab +
                                        data)
02F8  760 Dbl-Word     8 CHPHEADR (37)  Block header
     End of CHPBK definition
0420 1056 Dbl-Word     8 CHPRESVD (12)  Round it off
          00000318       CHPLENBY       *-CHPLOCK Extra space (after
                                        IORBK)
          00000480       CHPIOBY        *-CHPBK Whole work area size in
                                        bytes
          00000090       CHPIODW        CHPIOBY/8 Same in double words
          00000002       CHPBKCNT       2 Number of work areas per drive
     Redefinition for the channel program build area
0228  552 Dbl-Word     8 CHPMSCCW       Modeset, if applicable
0230  560 Address      4 CHPHDCCW       Read/write header CCW
0234  564 Address      4 CHPHCCWA       Address of the CHPHEADR
0238  568 Address      4 CHPCCW1        First general CCW
023C  572 Address      4 CHPCCW1A       Address section for deblocking
0240  576 Dbl-Word     8 CHPCCWS (20)   File write CCWs - desc, XAB, data
                                        Or read CCW's - up to 8 pages
          000000B8       CHPPGMLN       *-CHPPGM Must match size defined
                                        above
     Redefinition for the tape block header section
02F8  760 Character    4 CHPBLKID       Generally 'XHDR', could be 'TRLR'
02FC  764 Signed       4 CHPBLKSZ       Size of this block in bytes
0300  768 Dbl-Word     8 CHPTIME        Time stamp
     Definition of an individual entry
0308  776 Dbl-Word     8 CHPHDENT (0)   Start of the first entry
0308  776 Character    8 CHPOWNER       File owner
0310  784 Signed       4 CHPFSEQ        File sequence number for drive
0314  788 Signed       4 CHPSYSID       System spool file ID when dumped
0318  792 Signed       2 CHPSPID        User spool file ID when dumped
031A  794 Bitstring    1 CHPHDFLG       Flags describing file section
031B  795 Bitstring    1 *
031C  796 Signed       4 CHPMAPCT       Count of map pages needed for
                                        file
0320  800 Signed       4 CHPPAGNO       Starting relative page number
0324  804 Signed       2 CHPPAGCT       Count of data pages in block
0326  806 Signed       2 CHPXABSZ       Size of XAB section in block
0328  808 Signed       2 CHPTKOFF       Offset to ticket - file
                                        descriptor
032A  810 Signed       2 CHPXAOFF       Offset to extended attributes buf
032C  812 Signed       2 CHPDPOFF       Offset to data pages
032E  814 Signed       2 *

 

CHPBK Storage Layout

          
*** CHPBK - SPXTAPE Channel Program Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       CHPIORBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 168 |                                                       |
*     =                       CHPLOCK                         =
*     |                                                       |
*     +---------------------------+---------------------------+
* 180 |         CHPCURTK          |         CHPCMSSQ          |
*     +---------------------------+---------------------------+
* 188 |         CHPCMCUR          |         CHPCURHD          |
*     +---------------------------+---------------------------+
* 190 |         CHPCMXAB          |         CHPLSTCW          |
*     +---------------------------+---------------------------+
* 198 |         CHPLLPTR          |         CHPLSTHD          |
*     +---------------------------+---------------------------+
* 1A0 |         CHPLBLKZ          |                           |
*     +---------------------------+                           |
*     |                       CHPTKTS                         |
*     |                           +---------------------------+
*     |                           | 1B4
*     +---------------------------+
*
*** CHPBK - SPXTAPE Channel Program Block
          
*** Overlay for CHPTKTS in CHPBK
*
*                                 +---------------------------+
* 1A0 ...                     1A4 |         CHPTKTSH          |
*     +---------------------------+---------------------------+
* 1A8 |         CHPTKTST          |         CHPTKTCT          |
*     +---------------------------+---------------------------+
* 1B0 |///////////////////////////|         CHPENTRY          |
*     +---------------------------+---------------------------+
* 1B8 |         CHPLIMIT          |         CHPLINDX          |
*     +---------------------------+---------------------------+
* 1C0 |         CHPOFFST          |///////////////////////////|
*     +---------------------------+---------------------------+
* 1C8 |         CHPPOOLC          |                           |
*     +---------------------------+                           |
* 1D0 |                                                       |
*     =                       CHPPLIST                        =
*     |                           +---------------------------+
* 200 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 208 |         CHPNEXT           |                           |
*     +---------------------------+                           |
* 210 |                                                       |
*     =                       CHPSAVE                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 228 |                                                       |
*     =                        CHPPGM                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 2F8 |                                                       |
*     =                       CHPHEADR                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 420 |                                                       |
*     =                       CHPRESVD                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 480
*
*** Overlay for CHPTKTS in CHPBK
          
*** Overlay for CHPPGM in CHPBK
*
*     +-------------------------------------------------------+
* 228 |                       CHPMSCCW                        |
*     +---------------------------+---------------------------+
* 230 |         CHPHDCCW          |         CHPHCCWA          |
*     +---------------------------+---------------------------+
* 238 |         CHPCCW1           |         CHPCCW1A          |
*     +---------------------------+---------------------------+
* 240 |                                                       |
*     =                       CHPCCWS                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 2E0
*
*** Overlay for CHPPGM in CHPBK
          
*** Overlay for CHPHEADR in CHPBK
*
*     +---------------------------+---------------------------+
* 2F8 |         CHPBLKID          |         CHPBLKSZ          |
*     +---------------------------+---------------------------+
* 300 |                       CHPTIME                         |
*     +-------------------------------------------------------+
* 308 |                       CHPOWNER                        |
*     +---------------------------+---------------------------+
* 310 |         CHPFSEQ           |         CHPSYSID          |
*     +-------------+------+------+---------------------------+
* 318 |  CHPSPID    |:HDFLG|//////|         CHPMAPCT          |
*     +-------------+------+------+-------------+-------------+
* 320 |         CHPPAGNO          |  CHPPAGCT   |  CHPXABSZ   |
*     +-------------+-------------+-------------+-------------+
* 328 |  CHPTKOFF   |  CHPXAOFF   |  CHPDPOFF   |/////////////|
*     +-------------+-------------+-------------+-------------+
* 330
*
*** Overlay for CHPHEADR in CHPBK

 

CHPBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
CHPBKCNT       0420 00000002
CHPBLKID       02F8
CHPBLKSZ       02FC
CHPCCWS        0240
CHPCCW1        0238
CHPCCW1A       023C
CHPCMCLR       0180
CHPCMCRL       0204 00000088
CHPCMCUR       0188
CHPCMSSQ       0184
CHPCMXAB       0190
CHPCURHD       018C
CHPCURTK       0180
CHPDPOFF       032C
CHPENTRY       01B4
CHPFSEQ        0310
CHPHCCWA       0234
CHPHDCCW       0230
CHPHDENT       0308
CHPHDFLG       031A
CHPHEADR       02F8
CHPIOBY        0420 00000480
CHPIODW        0420 00000090
CHPIORBK       0000
CHPLBLKZ       01A0
CHPLENBY       0420 00000318
CHPLIMIT       01B8
CHPLINDX       01BC
CHPLLPTR       0198
CHPLOCK        0168
CHPLSTCW       0194
CHPLSTHD       019C
CHPMAPCT       031C
CHPMSCCW       0228
CHPNEXT        0208
CHPOFFST       01C0
CHPOWNER       0308
CHPPAGCT       0324
CHPPAGNO       0320
CHPPGM         0228
CHPPGMLN       0240 000000B8
CHPPLIST       01CC
CHPPLLEN       01CC 00000038
CHPPLMAX       01CC 0000000E
CHPPOOLC       01C8
CHPRESVD       0420
CHPSAVE        020C
CHPSPID        0318
CHPSYSID       0314
CHPTIME        0300
CHPTKOFF       0328
CHPTKTCT       01AC
CHPTKTS        01A4
CHPTKTSH       01A4
CHPTKTST       01A8
CHPXABSZ       0326
CHPXAOFF       032A

This information is based on z/VM V4R3.0. Last updated on 1 May 2002 at 08:09:02 EDT.
Copyright IBM Corporation, 1990, 2002