CHPBK - 32-bit CP - V4R4.0
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
 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 (57)  Base IORBK region
     Lock for this IORBK and CHPBK work area
01C8  456 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.
01E0  480 Signed       2 CHPCMCLR (0)   Beginning of area to be cleared
                                        before reuse for trailer
01E0  480 Address      4 CHPCURTK       Last ticket contained in current
                                        block
01E4  484 Address      4 CHPCMSSQ       Last SSQBK
01E8  488 Address      4 CHPCMCUR       Address of next Vpage slot in
                                        last SSQBK
01EC  492 Signed       4 CHPCURHD       Displacement in header of cur hdr
01F0  496 Signed       4 CHPCMXAB       Amt of XAB data associated with
                                        last tkt remaining to be written
01F4  500 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
01F8  504 Signed       4 CHPLLPTR       Last offset in page list +1 used
01FC  508 Address      4 CHPLSTHD       Hdr addr for last completed file
0200  512 Signed       4 CHPLBLKZ       Save last block size at last
                                        complete file/tkt in this block.
     Counters, etc.
0204  516 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
0204  516 Address      4 CHPTKTSH       Head of CHPTKTS
0208  520 Address      4 CHPTKTST       Tail of CHPTKTS
020C  524 Signed       4 CHPTKTCT       Corresponding count of files on
                                        CHPTKTS
0210  528 Signed       4 *              Reserved
0214  532 Signed       4 CHPENTRY       Current entry in the header
0218  536 Signed       4 CHPLIMIT       After the last entry in the hdr
021C  540 Signed       4 CHPLINDX       Index into CCW list of buffers
0220  544 Signed       4 CHPOFFST       Offset into block where data
                                        should be added
0224  548 Signed       4 *
0228  552 Signed       4 CHPPOOLC       Count of pool pages (data pages)
022C  556 Address      4 CHPPLIST (14)  List of pages locked for this blk
          00000038       CHPPLLEN       *-CHPPLIST Length to clear
          0000000E       CHPPLMAX       14 Maximum number of entries
0264  612 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
0268  616 Address      4 CHPNEXT        Next work area in circular queue
     Save area across GOTO I/O request
026C  620 Signed       4 CHPSAVE (7)    Save R3-R9 across call to IOS.QS
     Channel Program and Header Block copied from TAPBK
0288  648 Dbl-Word     8 CHPPGM (26)    Modeset + hdr + 3*8 (desc + xab +
                                        data)
0358  856 Dbl-Word     8 CHPHEADR (37)  Block header
     End of CHPBK definition
0480 1152 Dbl-Word     8 CHPRESVD (12)  Round it off
          00000318       CHPLENBY       *-CHPLOCK Extra space (after
                                        IORBK)
          000004E0       CHPIOBY        *-CHPBK Whole work area size in
                                        bytes
          0000009C       CHPIODW        CHPIOBY/8 Same in double words
          00000002       CHPBKCNT       2 Number of work areas per drive
     Redefinition for the channel program build area
0288  648 Dbl-Word     8 CHPMSCCW       Modeset, if applicable
0290  656 Address      4 CHPHDCCW       Read/write header CCW
0294  660 Address      4 CHPHCCWA       Address of the CHPHEADR
0298  664 Address      4 CHPCCW1        First general CCW
029C  668 Address      4 CHPCCW1A       Address section for deblocking
02A0  672 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
0358  856 Character    4 CHPBLKID       Generally 'XHDR', could be 'TRLR'
035C  860 Signed       4 CHPBLKSZ       Size of this block in bytes
0360  864 Dbl-Word     8 CHPTIME        Time stamp
     Definition of an individual entry
0368  872 Dbl-Word     8 CHPHDENT (0)   Start of the first entry
0368  872 Character    8 CHPOWNER       File owner
0370  880 Signed       4 CHPFSEQ        File sequence number for drive
0374  884 Signed       4 CHPSYSID       System spool file ID when dumped
0378  888 Signed       2 CHPSPID        User spool file ID when dumped
037A  890 Bitstring    1 CHPHDFLG       Flags describing file section
037B  891 Bitstring    1 *
037C  892 Signed       4 CHPMAPCT       Count of map pages needed for
                                        file
0380  896 Signed       4 CHPPAGNO       Starting relative page number
0384  900 Signed       2 CHPPAGCT       Count of data pages in block
0386  902 Signed       2 CHPXABSZ       Size of XAB section in block
0388  904 Signed       2 CHPTKOFF       Offset to ticket - file
                                        descriptor
038A  906 Signed       2 CHPXAOFF       Offset to extended attributes buf
038C  908 Signed       2 CHPDPOFF       Offset to data pages
038E  910 Signed       2 *

 

CHPBK Storage Layout

          
*** CHPBK - SPXTAPE Channel Program Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       CHPIORBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 1C8 |                                                       |
*     =                       CHPLOCK                         =
*     |                                                       |
*     +---------------------------+---------------------------+
* 1E0 |         CHPCURTK          |         CHPCMSSQ          |
*     +---------------------------+---------------------------+
* 1E8 |         CHPCMCUR          |         CHPCURHD          |
*     +---------------------------+---------------------------+
* 1F0 |         CHPCMXAB          |         CHPLSTCW          |
*     +---------------------------+---------------------------+
* 1F8 |         CHPLLPTR          |         CHPLSTHD          |
*     +---------------------------+---------------------------+
* 200 |         CHPLBLKZ          |                           |
*     +---------------------------+                           |
*     |                       CHPTKTS                         |
*     |                           +---------------------------+
*     |                           | 214
*     +---------------------------+
*
*** CHPBK - SPXTAPE Channel Program Block
          
*** Overlay for CHPTKTS in CHPBK
*
*                                 +---------------------------+
* 200 ...                     204 |         CHPTKTSH          |
*     +---------------------------+---------------------------+
* 208 |         CHPTKTST          |         CHPTKTCT          |
*     +---------------------------+---------------------------+
* 210 |///////////////////////////|         CHPENTRY          |
*     +---------------------------+---------------------------+
* 218 |         CHPLIMIT          |         CHPLINDX          |
*     +---------------------------+---------------------------+
* 220 |         CHPOFFST          |///////////////////////////|
*     +---------------------------+---------------------------+
* 228 |         CHPPOOLC          |                           |
*     +---------------------------+                           |
* 230 |                                                       |
*     =                       CHPPLIST                        =
*     |                           +---------------------------+
* 260 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 268 |         CHPNEXT           |                           |
*     +---------------------------+                           |
* 270 |                                                       |
*     =                       CHPSAVE                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 288 |                                                       |
*     =                        CHPPGM                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 358 |                                                       |
*     =                       CHPHEADR                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 480 |                                                       |
*     =                       CHPRESVD                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 4E0
*
*** Overlay for CHPTKTS in CHPBK
          
*** Overlay for CHPPGM in CHPBK
*
*     +-------------------------------------------------------+
* 288 |                       CHPMSCCW                        |
*     +---------------------------+---------------------------+
* 290 |         CHPHDCCW          |         CHPHCCWA          |
*     +---------------------------+---------------------------+
* 298 |         CHPCCW1           |         CHPCCW1A          |
*     +---------------------------+---------------------------+
* 2A0 |                                                       |
*     =                       CHPCCWS                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 340
*
*** Overlay for CHPPGM in CHPBK
          
*** Overlay for CHPHEADR in CHPBK
*
*     +---------------------------+---------------------------+
* 358 |         CHPBLKID          |         CHPBLKSZ          |
*     +---------------------------+---------------------------+
* 360 |                       CHPTIME                         |
*     +-------------------------------------------------------+
* 368 |                       CHPOWNER                        |
*     +---------------------------+---------------------------+
* 370 |         CHPFSEQ           |         CHPSYSID          |
*     +-------------+------+------+---------------------------+
* 378 |  CHPSPID    |:HDFLG|//////|         CHPMAPCT          |
*     +-------------+------+------+-------------+-------------+
* 380 |         CHPPAGNO          |  CHPPAGCT   |  CHPXABSZ   |
*     +-------------+-------------+-------------+-------------+
* 388 |  CHPTKOFF   |  CHPXAOFF   |  CHPDPOFF   |/////////////|
*     +-------------+-------------+-------------+-------------+
* 390
*
*** Overlay for CHPHEADR in CHPBK

 

CHPBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
CHPBKCNT       0480 00000002
CHPBLKID       0358
CHPBLKSZ       035C
CHPCCWS        02A0
CHPCCW1        0298
CHPCCW1A       029C
CHPCMCLR       01E0
CHPCMCRL       0264 00000088
CHPCMCUR       01E8
CHPCMSSQ       01E4
CHPCMXAB       01F0
CHPCURHD       01EC
CHPCURTK       01E0
CHPDPOFF       038C
CHPENTRY       0214
CHPFSEQ        0370
CHPHCCWA       0294
CHPHDCCW       0290
CHPHDENT       0368
CHPHDFLG       037A
CHPHEADR       0358
CHPIOBY        0480 000004E0
CHPIODW        0480 0000009C
CHPIORBK       0000
CHPLBLKZ       0200
CHPLENBY       0480 00000318
CHPLIMIT       0218
CHPLINDX       021C
CHPLLPTR       01F8
CHPLOCK        01C8
CHPLSTCW       01F4
CHPLSTHD       01FC
CHPMAPCT       037C
CHPMSCCW       0288
CHPNEXT        0268
CHPOFFST       0220
CHPOWNER       0368
CHPPAGCT       0384
CHPPAGNO       0380
CHPPGM         0288
CHPPGMLN       02A0 000000B8
CHPPLIST       022C
CHPPLLEN       022C 00000038
CHPPLMAX       022C 0000000E
CHPPOOLC       0228
CHPRESVD       0480
CHPSAVE        026C
CHPSPID        0378
CHPSYSID       0374
CHPTIME        0360
CHPTKOFF       0388
CHPTKTCT       020C
CHPTKTS        0204
CHPTKTSH       0204
CHPTKTST       0208
CHPXABSZ       0386
CHPXAOFF       038A

This information is based on z/VM V4R4.0. Last updated on 29 Jul 2003 at 15:18:15 EDT.
Copyright IBM Corporation, 1990, 2003