Programming Interface Information: This information is NOT intended to be
used as Programming Interfaces of VM/ESA. It is to be used for diagnosis only.

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
 STATUS     : VM/ESA Version 2, Release 3.0
 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 (IORSIZE) Base IORBK region Lock for this IORBK and CHPBK work area 0140 320 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. 0158 344 Signed 2 CHPCMCLR (0) Beginning of area to be cleared before reuse for trailer 0158 344 Address 4 CHPCURTK Last ticket contained in current block 015C 348 Address 4 CHPCMSSQ Last SSQBK 0160 352 Address 4 CHPCMCUR Address of next Vpage slot in last SSQBK 0164 356 Signed 4 CHPCURHD Displacement in header of cur hdr 0168 360 Signed 4 CHPCMXAB Amt of XAB data associated with last tkt remaining to be written 016C 364 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 0170 368 Signed 4 CHPLLPTR Last offset in page list +1 used 0174 372 Address 4 CHPLSTHD Hdr addr for last completed file 0178 376 Signed 4 CHPLBLKZ Save last block size at last complete file/tkt in this block. Counters, etc. 017C 380 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 017C 380 Address 4 CHPTKTSH Head of CHPTKTS 0180 384 Address 4 CHPTKTST Tail of CHPTKTS 0184 388 Signed 4 CHPTKTCT Corresponding count of files on CHPTKTS 0188 392 Signed 4 * Reserved 018C 396 Signed 4 CHPENTRY Current entry in the header 0190 400 Signed 4 CHPLIMIT After the last entry in the hdr 0194 404 Signed 4 CHPLINDX Index into CCW list of buffers 0198 408 Signed 4 CHPOFFST Offset into block where data should be added 019C 412 Signed 4 * 01A0 416 Signed 4 CHPPOOLC Count of pool pages (data pages) 01A4 420 Address 4 CHPPLIST (14) List of pages locked for this blk 00000038 CHPPLLEN *-CHPPLIST Length to clear 0000000E CHPPLMAX 14 Maximum number of entries 01DC 476 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 01E0 480 Address 4 CHPNEXT Next work area in circular queue Save area across GOTO I/O request 01E4 484 Signed 4 CHPSAVE (7) Save R3-R9 across call to IOS.QS Channel Program and Header Block copied from TAPBK 0200 512 Dbl-Word 8 CHPPGM (TAPCPLEN/8) Modeset + hdr + 3*8 (desc + xab + data) 02D0 720 Dbl-Word 8 CHPHEADR (TAPHDRSZ/8) Block header End of CHPBK definition 03F8 1016 Dbl-Word 8 CHPRESVD (12) Round it off 00000318 CHPLENBY *-CHPLOCK Extra space (after IORBK) 00000458 CHPIOBY *-CHPBK Whole work area size in bytes 0000008B CHPIODW CHPIOBY/8 Same in double words 00000002 CHPBKCNT 2 Number of work areas per drive Redefinition for the channel program build area 0200 512 Dbl-Word 8 CHPMSCCW Modeset, if applicable 0208 520 Address 4 CHPHDCCW Read/write header CCW 020C 524 Address 4 CHPHCCWA Address of the CHPHEADR 0210 528 Address 4 CHPCCW1 First general CCW 0214 532 Address 4 CHPCCW1A Address section for deblocking 0218 536 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 02D0 720 Character 4 CHPBLKID Generally 'XHDR', could be 'TRLR' 02D4 724 Signed 4 CHPBLKSZ Size of this block in bytes 02D8 728 Dbl-Word 8 CHPTIME Time stamp Definition of an individual entry 02E0 736 Dbl-Word 8 CHPHDENT (0) Start of the first entry 02E0 736 Character 8 CHPOWNER File owner 02E8 744 Signed 4 CHPFSEQ File sequence number for drive 02EC 748 Signed 4 CHPSYSID System spool file ID when dumped 02F0 752 Signed 2 CHPSPID User spool file ID when dumped 02F2 754 Bitstring 1 CHPHDFLG Flags describing file section 02F3 755 Bitstring 1 * 02F4 756 Signed 4 CHPMAPCT Count of map pages needed for file 02F8 760 Signed 4 CHPPAGNO Starting relative page number 02FC 764 Signed 2 CHPPAGCT Count of data pages in block 02FE 766 Signed 2 CHPXABSZ Size of XAB section in block 0300 768 Signed 2 CHPTKOFF Offset to ticket - file descriptor 0302 770 Signed 2 CHPXAOFF Offset to extended attributes buf 0304 772 Signed 2 CHPDPOFF Offset to data pages 0306 774 Signed 2 *

 

CHPBK Storage Layout

*** CHPBK - SPXTAPE Channel Program Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       CHPIORBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 140 |                                                       |
*     =                       CHPLOCK                         =
*     |                                                       |
*     +---------------------------+---------------------------+
* 158 |         CHPCURTK          |         CHPCMSSQ          |
*     +---------------------------+---------------------------+
* 160 |         CHPCMCUR          |         CHPCURHD          |
*     +---------------------------+---------------------------+
* 168 |         CHPCMXAB          |         CHPLSTCW          |
*     +---------------------------+---------------------------+
* 170 |         CHPLLPTR          |         CHPLSTHD          |
*     +---------------------------+---------------------------+
* 178 |         CHPLBLKZ          |                           |
*     +---------------------------+                           |
*     |                       CHPTKTS                         |
*     |                           +---------------------------+
*     |                           | 18C
*     +---------------------------+
*
*** CHPBK - SPXTAPE Channel Program Block
*** Overlay for CHPTKTS in CHPBK
*
*                                 +---------------------------+
* 178 ...                     17C |         CHPTKTSH          |
*     +---------------------------+---------------------------+
* 180 |         CHPTKTST          |         CHPTKTCT          |
*     +---------------------------+---------------------------+
* 188 |///////////////////////////|         CHPENTRY          |
*     +---------------------------+---------------------------+
* 190 |         CHPLIMIT          |         CHPLINDX          |
*     +---------------------------+---------------------------+
* 198 |         CHPOFFST          |///////////////////////////|
*     +---------------------------+---------------------------+
* 1A0 |         CHPPOOLC          |                           |
*     +---------------------------+                           |
* 1A8 |                                                       |
*     =                       CHPPLIST                        =
*     |                           +---------------------------+
* 1D8 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 1E0 |         CHPNEXT           |                           |
*     +---------------------------+                           |
* 1E8 |                                                       |
*     =                       CHPSAVE                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 200 |                                                       |
*     =                        CHPPGM                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 2D0 |                                                       |
*     =                       CHPHEADR                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 3F8 |                                                       |
*     =                       CHPRESVD                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 458
*
*** Overlay for CHPTKTS in CHPBK
*** Overlay for CHPPGM in CHPBK
*
*     +-------------------------------------------------------+
* 200 |                       CHPMSCCW                        |
*     +---------------------------+---------------------------+
* 208 |         CHPHDCCW          |         CHPHCCWA          |
*     +---------------------------+---------------------------+
* 210 |         CHPCCW1           |         CHPCCW1A          |
*     +---------------------------+---------------------------+
* 218 |                                                       |
*     =                       CHPCCWS                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 2B8
*
*** Overlay for CHPPGM in CHPBK
*** Overlay for CHPHEADR in CHPBK
*
*     +---------------------------+---------------------------+
* 2D0 |         CHPBLKID          |         CHPBLKSZ          |
*     +---------------------------+---------------------------+
* 2D8 |                       CHPTIME                         |
*     +-------------------------------------------------------+
* 2E0 |                       CHPOWNER                        |
*     +---------------------------+---------------------------+
* 2E8 |         CHPFSEQ           |         CHPSYSID          |
*     +-------------+------+------+---------------------------+
* 2F0 |  CHPSPID    |:HDFLG|//////|         CHPMAPCT          |
*     +-------------+------+------+-------------+-------------+
* 2F8 |         CHPPAGNO          |  CHPPAGCT   |  CHPXABSZ   |
*     +-------------+-------------+-------------+-------------+
* 300 |  CHPTKOFF   |  CHPXAOFF   |  CHPDPOFF   |/////////////|
*     +-------------+-------------+-------------+-------------+
* 308
*
*** Overlay for CHPHEADR in CHPBK

 

CHPBK Cross Reference

(contains links to field and bit definitions)
Symbol         Dspl Value
-------------- ---- -----

CHPBKCNT 03F8 00000002

CHPBLKID 02D0

CHPBLKSZ 02D4

CHPCCWS 0218

CHPCCW1 0210

CHPCCW1A 0214

CHPCMCLR 0158

CHPCMCRL 01DC 00000088

CHPCMCUR 0160

CHPCMSSQ 015C

CHPCMXAB 0168

CHPCURHD 0164

CHPCURTK 0158

CHPDPOFF 0304

CHPENTRY 018C

CHPFSEQ 02E8

CHPHCCWA 020C

CHPHDCCW 0208

CHPHDENT 02E0

CHPHDFLG 02F2

CHPHEADR 02D0

CHPIOBY 03F8 00000458

CHPIODW 03F8 0000008B

CHPIORBK 0000

CHPLBLKZ 0178

CHPLENBY 03F8 00000318

CHPLIMIT 0190

CHPLINDX 0194

CHPLLPTR 0170

CHPLOCK 0140

CHPLSTCW 016C

CHPLSTHD 0174

CHPMAPCT 02F4

CHPMSCCW 0200

CHPNEXT 01E0

CHPOFFST 0198

CHPOWNER 02E0

CHPPAGCT 02FC

CHPPAGNO 02F8

CHPPGM 0200

CHPPGMLN 0218 000000B8

CHPPLIST 01A4

CHPPLLEN 01A4 00000038

CHPPLMAX 01A4 0000000E

CHPPOOLC 01A0

CHPRESVD 03F8

CHPSAVE 01E4

CHPSPID 02F0

CHPSYSID 02EC

CHPTIME 02D8

CHPTKOFF 0300

CHPTKTCT 0184

CHPTKTS 017C

CHPTKTSH 017C

CHPTKTST 0180

CHPXABSZ 02FE

CHPXAOFF 0302


This information is based on VM/ESA 2.4.0.
Last updated on 3 Aug 1999 at 11:45:24 EDT.
Copyright IBM Corporation, 1990, 1999