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Prolog 
Control Block Contents 
   DIOSECT 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.


  DIOSECT Prolog Top of page
 
 NAME       : DIOSECT
 DESCRIPTION: Disk I/O Work Area
 DSECT      : DIOSECT
 NOTES      : MODULE TYPE - Macro
 FUNCTION   : This is the bilingual macro
              containing the mapping of the disk I/O work
              area used primarily by module DMSDIO. DIOSECT
              describes the fields used by DMSDIO as a work
              area when reading and writing actual blocks of
              data on CMS disks. DIOSECT is pointed to by a
              V-constant in DMSNUC, and referenced indirectly
              by ADIOSECT in NUCON.
 
 
  DIOSECT Control Block Content Top of page
 

 DIOSECT DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure DIOSECT Disk I/O Work Area 0000 0 Dbl-Word 8 IOOLD IO-OLD-PSW (FROM INTERRUPT ROUTINE) 0008 8 Dbl-Word 8 DIOCSW CSW (FROM INTERRUPT ROUTINE) WAIT CALLING SEQUENCE 0010 16 Signed 4 * (0) 0010 16 Character 8 PWAIT 0018 24 Character 4 * FILLED IN TO CORRECT SYMBOLIC DISK NO. 001C 28 Signed 4 * 0020 32 Signed 4 * 0024 36 Signed 4 QQDSK1 1ST TWO BYTES ALWAYS = 0 ..1. .11. QQDSK2 QQDSK1+2 QQDSK2 HALFWORD COPY OF 16TH TRACK DISK-ADDRESS CCW CHAIN 0050 80 Bitstring 7 SEEKADR SEEK/SEARCH INFO (1ST 3 BYTES ARE 0) 0057 87 Bitstring 1 SECTNUM SECTOR NUMBER FBA CCWS FOR USE IN ONE-CMS-BLK OPERATIONS FULL MINIDISK NEXT OPERATION DEFINE EXTENT LIST 0070 112 Bitstring 1 FBACD1 MASK 0071 113 Bitstring 3 * RESERVED 0074 116 Signed 4 FBACD1MO MAJOR OFFSET 0078 120 Signed 4 FBACD1FB FIRST BLOCK OFFSET 007C 124 Signed 4 FBACD1LB LAST BLOCK OFFSET LOCATE LIST 0080 128 Bitstring 1 FBACL1 OPERATION 0081 129 Bitstring 1 * AUX BYTE 0082 130 Signed 2 FBACL1NB NUMBER OF BLKS 0084 132 Signed 4 FBACL1BO BLOCK OFFSET I/O INFO 0088 136 Signed 4 LASTCYL BECOMES 'LAST CYLINDER-NUMBER USED' 008C 140 Signed 4 LASTHED BECOMES 'LAST HEAD-NUMBER USED' 0090 144 Bitstring 1 DEVTYP Device type from the DEVTAB 0091 145 Bitstring 1 DIOFLAG RDTK/WRTK FLAG: .1.. .... DIODYBUF X'40' DIODYBUF DYnamic BUFfer obtained ..1. .... DIOFLSB X'20' DIOFLSB Sense bytes stored on I/O error ...1 .... DIOFLCSW X'10' DIOFLCSW CSW stored on I/O error .... .1.. TOOBIG X'04' TOOBIG BYTE-COUNT > 800 .... ..1. WRTKF X'02' WRTKF WRITING FIRST CHAIN LINK .... ...1 QQTRK X'01' QQTRK HANDLING FIRST CHAIN LINK ...1 1... DIAGNUM 24 DIAGNUM **** NUMBER ASSIGNED BY 'CP' FOR DIAGNOSE I/O .... .1.. DIOBKWTH 4 DIOBKWTH Default block width is 4.. 0098 152 Dbl-Word 8 * (0) 0098 152 Bitstring 32 SENSB SENSE INFORMATION MISCELLANEOUS STORAGE 00C0 192 Dbl-Word 8 DOUBLE (SCRATCH-AREA, FOR CVD USE ETC.) KEEP THE FOLLOWING THREE IN ORDER 00C8 200 Signed 4 XRSAVE (15) REGISTERS 0-14 SAVED HERE FOR RDTK-WRTK 0104 260 Address 3 * FIRST 3 BYTES OF R15 ERROR-CODE 0107 263 Address 1 ERRCODE ERROR-CODE (IN R15 AT EXIT) KEEP THE FOLLOWING TWO IN ORDER 0108 264 Signed 4 FREER0 NO. DBL-WORDS OF FREE STORAGE (IF ANY) 010C 268 Signed 4 DIOFREE ADD. OF FREE STORAGE FOR BUFFER OR CCW'S 0110 272 Signed 2 DIOSNSCT SENSE BYTE COUNT 0112 274 Signed 2 * RESERVED 0120 288 Bitstring 1 DIAGRET CP'S DIAGNOSE RETURN CODE IF NON-ZERO 0121 289 Bitstring 1 IOCOMM SET TO READ (06) OR WRITE (05) 0122 290 Bitstring 1 LASTREC NUMBER (1-14) OF THE LAST RECORD PROCESSED 0128 296 Dbl-Word 8 DIOCCW01 (128) CCW BUILD AREA FOR LONG OPERATIONS VA09499 00000080 DIOCCWLN (*-DIOCCW01)/8 Number of Dwords in work area 0528 1320 Signed 4 DIODIEPL (7) Reserve storage for DISKDIE parameter list 0544 1348 Signed 4 * Reserved 0548 1352 Dbl-Word 8 * (0) 0128 296 Signed 4 DIOBUFEN Max number of SBILIST entries that can be built in the workarea 0130 304 Dbl-Word 8 DIOSBIOP (11) SBIOP block build area 0000000C DIODWUSD (*-DIOCCW01)/8 Number of d-words used 0188 392 Dbl-Word 8 DIOSBL01 (0) SBILIST build area .111 .1.. DIOSBLMX DIOCCWLN-DIODWUSD DIOSBLMX Number of SBILISTS buildable static save area ECKD CCW CHAIN 0560 1376 Signed 4 * (0) Set up alignment 0560 1376 Bitstring 16 DIODEX (0) Define extent parameter list 0560 1376 Bitstring 1 DIOMASK Mask byte 0561 1377 Bitstring 1 DIOATTRB Extended CKD implemented 0562 1378 Signed 2 DIOBLKSZ Maximum block size allowed 0564 1380 Bitstring 3 * RESERVED /*VA59119*/ 0567 1383 Bitstring 1 DIOGLOA7 Global attribute byte seven /*VA59119*/ .1.. .1.. DIOR0FMT X'44' DIOR0FMT Standard Record Format /*VA64602* Standard R0 /*VA64602*/ 0568 1384 Signed 2 DIOBEGCC Beginning cylinder extent 056A 1386 Signed 2 DIOBEGHH Beginning head extent 056C 1388 Signed 2 DIOENDCC End cylinder extent 056E 1390 Signed 2 DIOENDHH End head extent 0570 1392 Signed 4 * (0) Set up alignment 0570 1392 Bitstring 16 DIOLOC (0) Locate record parameter list 0570 1392 Bitstring 1 DIOOPBYT OP code byte 0571 1393 Bitstring 1 DIOAUX Auxiliary byte 0572 1394 Bitstring 1 * RESERVED - SET TO ZEROS 0573 1395 Bitstring 1 DIORECNO Number of records to process 0574 1396 Signed 2 DIOSEEKC Seek cylinder 0576 1398 Signed 2 DIOSEEKH Seek head 0578 1400 Signed 2 DIOSRCHC Search cylinder 057A 1402 Signed 2 DIOSRCHH Search head 057C 1404 Bitstring 1 DIOSRCHR Search record number 057D 1405 Bitstring 1 DIOSSECT Sector number 057E 1406 Signed 2 DIOTLF Transfer length factor ** CMS EQUATE SYMBOLS
 
 
  DIOSECT Storage Layout Top of page
 
          
*** DIOSECT - Disk I/O Work Area
*
*     +-------------------------------------------------------+
*   0 |                        IOOLD                          |
*     +-------------------------------------------------------+
*   8 |                        DIOCSW                         |
*     +-------------------------------------------------------+
*  10 |                        PWAIT                          |
*     +---------------------------+---------------------------+
*  18 |///////////////////////////|///////////////////////////|
*     +---------------------------+---------------------------+
*  20 |///////////////////////////|          QQDSK1           |
*     +---------------------------+---------------------------+
*  28 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------------------------------------------------+------+
*  50 |                    SEEKADR                     |:TNUM |
*     +------------------------------------------------+------+
*  58 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------+--------------------+---------------------------+
*  70 |FBACD1|////////////////////|         FBACD1MO          |
*     +------+--------------------+---------------------------+
*  78 |         FBACD1FB          |         FBACD1LB          |
*     +------+------+-------------+---------------------------+
*  80 |FBACL1|//////|  FBACL1NB   |         FBACL1BO          |
*     +------+------+-------------+---------------------------+
*  88 |         LASTCYL           |         LASTHED           |
*     +------+------+-------------+---------------------------+
*  90 |DEVTYP|:FLAG |/////////////////////////////////////////|
*     +------+------+-----------------------------------------+
*  98 |                                                       |
*     =                        SENSB                          =
*     |                                                       |
*     +-------------------------------------------------------+
*  B8 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  C0 |                        DOUBLE                         |
*     +-------------------------------------------------------+
*  C8 |                                                       |
*     =                        XRSAVE                         =
*     |                           +--------------------+------+
* 100 |                           |////////////////////|:CODE |
*     +---------------------------+--------------------+------+
* 108 |          FREER0           |         DIOFREE           |
*     +-------------+-------------+---------------------------+
* 110 |  DIOSNSCT   |/////////////|///////////////////////////|
*     +-------------+-------------+///////////////////////////|
*     |///////////////////////////////////////////////////////|
*     +------+------+------+----------------------------------+
* 120 |:GRET |IOCOMM|:TREC |//////////////////////////////////|
*     +------+------+------+----------------------------------+
* 128 |                                                       |
*     =                       DIOCCW01                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 528 |                                                       |
*     =                       DIODIEPL                        =
*     |                           +---------------------------+
* 540 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 548 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------+------+-------------+--------------------+------+
* 560 |:MASK |:ATTRB|  DIOBLKSZ   |////////////////////|:GLOA7|
*     +------+------+-------------+-------------+------+------+
* 568 |  DIOBEGCC   |  DIOBEGHH   |  DIOENDCC   |  DIOENDHH   |
*     +------+------+------+------+-------------+-------------+
* 570 |:OPBYT|DIOAUX|//////|:RECNO|  DIOSEEKC   |  DIOSEEKH   |
*     +------+------+------+------+------+------+-------------+
* 578 |  DIOSRCHC   |  DIOSRCHH   |:SRCHR|:SSECT|   DIOTLF    |
*     +-------------+-------------+------+------+-------------+
* 580
*
*** DIOSECT - Disk I/O Work Area
          
*** Overlay for DIOCCW01 in DIOSECT
*
*     +---------------------------+---------------------------+
* 128 |         DIOBUFEN          |///////////////////////////|
*     +---------------------------+---------------------------+
* 130 |                                                       |
*     =                       DIOSBIOP                        =
*     |                                                       |
*     +-------------------------------------------------------+
*
*** Overlay for DIOCCW01 in DIOSECT
 
 
  DIOSECT Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
DEVTYP         0090
DIAGNUM        0091 18
DIAGRET        0120
DIOATTRB       0561
DIOAUX         0571
DIOBEGCC       0568
DIOBEGHH       056A
DIOBKWTH       0091 04
DIOBLKSZ       0562
DIOBUFEN       0128
DIOCCWLN       0128 00000080
DIOCCW01       0128
DIOCSW         0008
DIODEX         0560
DIODIEPL       0528
DIODWUSD       0130 0000000C
DIODYBUF       0091 40
DIOENDCC       056C
DIOENDHH       056E
DIOFLAG        0091
DIOFLCSW       0091 10
DIOFLSB        0091 20
DIOFREE        010C
DIOGLOA7       0567
DIOLOC         0570
DIOMASK        0560
DIOOPBYT       0570
DIORECNO       0573
DIOR0FMT       0567 44
DIOSBIOP       0130
DIOSBLMX       0188 74
DIOSBL01       0188
DIOSEEKC       0574
DIOSEEKH       0576
DIOSNSCT       0110
DIOSRCHC       0578
DIOSRCHH       057A
DIOSRCHR       057C
DIOSSECT       057D
DIOTLF         057E
DOUBLE         00C0
ERRCODE        0107
FBACD1         0070
FBACD1FB       0078
FBACD1LB       007C
FBACD1MO       0074
FBACL1         0080
FBACL1BO       0084
FBACL1NB       0082
FREER0         0108
IOCOMM         0121
IOOLD          0000
LASTCYL        0088
LASTHED        008C
LASTREC        0122
PWAIT          0010
QQDSK1         0024
QQDSK2         0024 26
QQTRK          0091 01
SECTNUM        0057
SEEKADR        0050
SENSB          0098
TOOBIG         0091 04
WRTKF          0091 02
XRSAVE         00C8
 
This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:36:08 EDT.
Copyright IBM Corporation, 1990, 2020