CHPBK Back to Index page
 
Prolog 
Control Block Contents 
   CHPBK 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.


  CHPBK Prolog Top of page
  
 NAME       : HCPCHPBK
 DESCRIPTION: SPXTAPE Channel Program Block
 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
 RELOCATION CONSIDERATIONS : None
 
 
  CHPBK Control Block Content Top of page
  




 CHPBK DSECT
Top of page


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 (83)  Base IORBK region
        Lock for this IORBK and CHPBK work area
0298  664 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.
02B0  688 Signed       2 CHPCMCLR (0)   Beginning of area to be cleared
                                        before reuse for trailer
02B0  688 Address      4 CHPCURTK       Last ticket contained in current
                                        block
02B4  692 Address      4 CHPCMSSQ       Last SSQBK
02B8  696 Address      4 CHPCMCUR       Address of next Vpage slot in
                                        last SSQBK
02BC  700 Signed       4 CHPCURHD       Displacement in header of cur hdr
02C0  704 Signed       4 CHPCMXAB       Amt of XAB data associated with
                                        last tkt remaining to be written
02C4  708 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
02C8  712 Signed       4 CHPLLPTR       Last offset in page list +1 used
02CC  716 Address      4 CHPLSTHD       Hdr addr for last completed file
02D0  720 Signed       4 CHPLBLKZ       Save last block size at last
                                        complete file/tkt in this block.
        Counters, etc.
02D4  724 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
02D4  724 Address      4 CHPTKTSH       Head of CHPTKTS
02D8  728 Address      4 CHPTKTST       Tail of CHPTKTS
02DC  732 Signed       4 CHPTKTCT       Corresponding count of files on
                                        CHPTKTS
02E0  736 Signed       4 *              Reserved
02E4  740 Signed       4 CHPENTRY       Current entry in the header
02E8  744 Signed       4 CHPLIMIT       After the last entry in the hdr
02EC  748 Signed       4 CHPLINDX       Index into CCW list of buffers
02F0  752 Signed       4 CHPOFFST       Offset into block where data
                                        should be added
02F4  756 Signed       4 *
02F8  760 Signed       4 CHPPOOLC       Count of pool pages (data pages)
02FC  764 Address      4 CHPPLIST (14)  List of pages locked for this blk
          00000038       CHPPLLEN       *-CHPPLIST Length to clear
          0000000E       CHPPLMAX       14 Maximum number of entries
0334  820 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
0338  824 Address      4 CHPNEXT        Next work area in circular queue
        Save area across GOTO I/O request
033C  828 Signed       4 CHPSAVE (7)    Save R3-R9 across call to IOS.QS
        Channel Program and Header Block copied from TAPBK
0358  856 Dbl-Word     8 CHPPGM (26)    Modeset + hdr + 3*8 (desc + xab +
                                        data)
0428 1064 Dbl-Word     8 CHPHEADR (37)  Block header
        Pointers
0550 1360 Signed       4 CHPIDAWA       IDAW list anchor
0554 1364 Signed       4 CHPIDWNX       Next available IDAW slot
0558 1368 Signed       4 CHPBUFHL       Host logical buffer addr anchor
055C 1372 Signed       4 *              Reserved
          00000004       CHPHLLEN       4 Length of CHPBUFHL entries
        End of CHPBK definition
0560 1376 Dbl-Word     8 CHPRESVD (10)  Round it off
          00000318       CHPLENBY       *-CHPLOCK Extra space (after
                                        IORBK)
          000005B0       CHPIOBY        *-CHPBK Whole work area size in
                                        bytes
          000000B6       CHPIODW        CHPIOBY/8 Same in double words
          00000002       CHPBKCNT       2 Number of work areas per drive
        Redefinition for the channel program build area
0358  856 Dbl-Word     8 CHPMSCCW       Modeset, if applicable
0360  864 Address      4 CHPHDCCW       Read/write header CCW
0364  868 Address      4 CHPHCCWA       Address of the CHPHEADR
0368  872 Address      4 CHPCCW1        First general CCW
036C  876 Address      4 CHPCCW1A       Address section for deblocking
0370  880 Dbl-Word     8 CHPCCWS (20)   File write CCWs - desc, XAB, data
                                        Or read CCW's - up to 8 pages
          00000015       CHPCCWCT       (*-CHPCCW1)/8 Number of CCWs
                                        (doublewords)
          000000B8       CHPPGMLN       *-CHPPGM Must match size defined
                                        above
        Redefinition for the tape block header section
0428 1064 Character    4 CHPBLKID       Generally 'XHDR', could be 'TRLR'
042C 1068 Signed       4 CHPBLKSZ       Size of this block in bytes
0430 1072 Dbl-Word     8 CHPTIME        Time stamp
        Definition of an individual entry
0438 1080 Dbl-Word     8 CHPHDENT (0)   Start of the first entry
0438 1080 Character    8 CHPOWNER       File owner
0440 1088 Signed       4 CHPFSEQ        File sequence number for drive
0444 1092 Signed       4 CHPSYSID       System spool file ID when dumped
0448 1096 Signed       2 CHPSPID        User spool file ID when dumped
044A 1098 Bitstring    1 CHPHDFLG       Flags describing file section
044B 1099 Bitstring    1 *
044C 1100 Signed       4 CHPMAPCT       Count of map pages needed for
                                        file
0450 1104 Signed       4 CHPPAGNO       Starting relative page number
0454 1108 Signed       2 CHPPAGCT       Count of data pages in block
0456 1110 Signed       2 CHPXABSZ       Size of XAB section in block
0458 1112 Signed       2 CHPTKOFF       Offset to ticket - file
                                        descriptor
045A 1114 Signed       2 CHPXAOFF       Offset to extended attributes buf
045C 1116 Signed       2 CHPDPOFF       Offset to data pages
045E 1118 Signed       2 *
 
 
  CHPBK Storage Layout Top of page
  
          
*** CHPBK - SPXTAPE Channel Program Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       CHPIORBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 298 |                                                       |
*     =                       CHPLOCK                         =
*     |                                                       |
*     +---------------------------+---------------------------+
* 2B0 |         CHPCURTK          |         CHPCMSSQ          |
*     +---------------------------+---------------------------+
* 2B8 |         CHPCMCUR          |         CHPCURHD          |
*     +---------------------------+---------------------------+
* 2C0 |         CHPCMXAB          |         CHPLSTCW          |
*     +---------------------------+---------------------------+
* 2C8 |         CHPLLPTR          |         CHPLSTHD          |
*     +---------------------------+---------------------------+
* 2D0 |         CHPLBLKZ          |                           |
*     +---------------------------+                           |
*     |                       CHPTKTS                         |
*     |                           +---------------------------+
*     |                           | 2E4
*     +---------------------------+
*
*** CHPBK - SPXTAPE Channel Program Block
          
*** Overlay for CHPTKTS in CHPBK
*
*                                 +---------------------------+
* 2D0 ...                     2D4 |         CHPTKTSH          |
*     +---------------------------+---------------------------+
* 2D8 |         CHPTKTST          |         CHPTKTCT          |
*     +---------------------------+---------------------------+
* 2E0 |///////////////////////////|         CHPENTRY          |
*     +---------------------------+---------------------------+
* 2E8 |         CHPLIMIT          |         CHPLINDX          |
*     +---------------------------+---------------------------+
* 2F0 |         CHPOFFST          |///////////////////////////|
*     +---------------------------+---------------------------+
* 2F8 |         CHPPOOLC          |                           |
*     +---------------------------+                           |
* 300 |                                                       |
*     =                       CHPPLIST                        =
*     |                           +---------------------------+
* 330 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 338 |         CHPNEXT           |                           |
*     +---------------------------+                           |
* 340 |                                                       |
*     =                       CHPSAVE                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 358 |                                                       |
*     =                        CHPPGM                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 428 |                                                       |
*     =                       CHPHEADR                        =
*     |                                                       |
*     +---------------------------+---------------------------+
* 550 |         CHPIDAWA          |         CHPIDWNX          |
*     +---------------------------+---------------------------+
* 558 |         CHPBUFHL          |///////////////////////////|
*     +---------------------------+---------------------------+
* 560 |                                                       |
*     =                       CHPRESVD                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 5B0
*
*** Overlay for CHPTKTS in CHPBK
          
*** Overlay for CHPPGM in CHPBK
*
*     +-------------------------------------------------------+
* 358 |                       CHPMSCCW                        |
*     +---------------------------+---------------------------+
* 360 |         CHPHDCCW          |         CHPHCCWA          |
*     +---------------------------+---------------------------+
* 368 |         CHPCCW1           |         CHPCCW1A          |
*     +---------------------------+---------------------------+
* 370 |                                                       |
*     =                       CHPCCWS                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 410
*
*** Overlay for CHPPGM in CHPBK
          
*** Overlay for CHPHEADR in CHPBK
*
*     +---------------------------+---------------------------+
* 428 |         CHPBLKID          |         CHPBLKSZ          |
*     +---------------------------+---------------------------+
* 430 |                       CHPTIME                         |
*     +-------------------------------------------------------+
* 438 |                       CHPOWNER                        |
*     +---------------------------+---------------------------+
* 440 |         CHPFSEQ           |         CHPSYSID          |
*     +-------------+------+------+---------------------------+
* 448 |  CHPSPID    |:HDFLG|//////|         CHPMAPCT          |
*     +-------------+------+------+-------------+-------------+
* 450 |         CHPPAGNO          |  CHPPAGCT   |  CHPXABSZ   |
*     +-------------+-------------+-------------+-------------+
* 458 |  CHPTKOFF   |  CHPXAOFF   |  CHPDPOFF   |/////////////|
*     +-------------+-------------+-------------+-------------+
* 460
*
*** Overlay for CHPHEADR in CHPBK
 
 
  CHPBK Cross Reference Top of page
  
 
Symbol         Dspl Value
-------------- ---- -----
CHPBKCNT       0560 00000002
CHPBLKID       0428
CHPBLKSZ       042C
CHPBUFHL       0558
CHPCCWCT       0370 00000015
CHPCCWS        0370
CHPCCW1        0368
CHPCCW1A       036C
CHPCMCLR       02B0
CHPCMCRL       0334 00000088
CHPCMCUR       02B8
CHPCMSSQ       02B4
CHPCMXAB       02C0
CHPCURHD       02BC
CHPCURTK       02B0
CHPDPOFF       045C
CHPENTRY       02E4
CHPFSEQ        0440
CHPHCCWA       0364
CHPHDCCW       0360
CHPHDENT       0438
CHPHDFLG       044A
CHPHEADR       0428
CHPHLLEN       055C 00000004
CHPIDAWA       0550
CHPIDWNX       0554
CHPIOBY        0560 000005B0
CHPIODW        0560 000000B6
CHPIORBK       0000
CHPLBLKZ       02D0
CHPLENBY       0560 00000318
CHPLIMIT       02E8
CHPLINDX       02EC
CHPLLPTR       02C8
CHPLOCK        0298
CHPLSTCW       02C4
CHPLSTHD       02CC
CHPMAPCT       044C
CHPMSCCW       0358
CHPNEXT        0338
CHPOFFST       02F0
CHPOWNER       0438
CHPPAGCT       0454
CHPPAGNO       0450
CHPPGM         0358
CHPPGMLN       0370 000000B8
CHPPLIST       02FC
CHPPLLEN       02FC 00000038
CHPPLMAX       02FC 0000000E
CHPPOOLC       02F8
CHPRESVD       0560
CHPSAVE        033C
CHPSPID        0448
CHPSYSID       0444
CHPTIME        0430
CHPTKOFF       0458
CHPTKTCT       02DC
CHPTKTS        02D4
CHPTKTSH       02D4
CHPTKTST       02D8
CHPXABSZ       0456
CHPXAOFF       045A
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:48:03 EDT.
Copyright IBM Corporation, 1990, 2022