IORBK - 64-bit CP - V4R4.0

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

#### IORBK

Prolog

Control Block Contents
IORBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### IORBK Prolog

     NAME       : HCPIORBK
     DESCRIPTION: I/O Request and Response Block
     DSECT      : IORBK
     FUNCTION   : THE I/O REQUEST AND RESPONSE BLOCK IS USED
                  TO REPRESENT AN I/O OPERATION.
     LOCATED BY : CACXUIOR FIELD OF CACBK - CTC UNSOLICITED IORBK
                  CACYUIOR FIELD OF CACBK - CTC UNSOLICITED IORBK
                  CPVIORS  FIELD OF CPVOL - PREFORMATTED PAGING IORBK
                  GSRIORBK FIELD OF GSRBK - IORBK'S FOR RECOVERY
                  IORFPNT  FIELD OF IORBK - FORWARD  IORBK POINTER
                  IORBPNT  FIELD OF IORBK - BACKWARD IORBK POINTER
                  IORPIOR  FIELD OF IORBK - NEXT PENDING INTERRUPTION IORBK
                  MDIDEOWD FIELD OF MDISK - DEVICE-END OWED IORBK
                  MDIDEPND FIELD OF MDISK - DEVICE-END PENDING IORBK
                  MDIQWAIT FILED OF MDISK - WAIT FOR "RELEASE" IORBK
                  MNDAIOR  FIELD OF MNDC  - MONITOR TAPE IORBK
                  PIOIOR   FIELD OF PIOBK - IORBK FOR THIS PIOBK
                  RDEVAIOR FIELD OF RDEV  - ACTIVE IORBK
                  RDEVNXTL FIELD OF RDEV  - NEXT LOWER  IORBK
                  RDEVNXTH FIELD OF RDEV  - NEXT HIGHER IORBK
                  RDEVNXTI FIELD OF RDEV  - NEXT IMMEDIATE IORBK
                  RDEVNXTW FIELD OF RDEV  - INTER-REQUIRED WAIT IORBK
                  VCTXDATN FIELD OF VCTCA - DEFERRED ATTENTION IORBK
                  VCTYDATN FIELD OF VCTCA - DEFERRED ATTENTION IORBK
                  VDEVAIOR FIELD OF VDEV  - ACTIVE IORBK
                  VDEVIORQ FIELD OF VDEV  - UNSOLICITED INTERRUPT IORBK
                  VDEVNIOR FIELD OF VDEV  - REDRIVE/SUSPENDED IORBK
                  VDEVPIOR FIELD OF VDEV  - PENDING INTERRUPT IORBK
                  VDEVSIOR FIELD OF VDEV  - PENDING SENSE DATA IORBK
                  VMDQIORF FIELD OF VMDBK - IORBK/TRQBK STACK
     CREATED BY : IORBK'S ARE DYNAMICALLY CREATED BY CALLING HCPFREE.
     DELETED BY : IORBK'S ARE DELETED BY CALLING HCPFRET.

#### IORBK Control Block Content

#### IORBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      IORBK          I/O Request and Response Block
         WARNING - THE FIRST THREE DOUBLE WORDS MUST BE IDENTICAL TO THE TRQBK
         COPY FILE.
    0000    0 Signed       4 IORUSER        VIRTUAL USER TO BE CHARGED
    0004    4 Signed       4 IORIRA         I/O INTERRUPTION RETURN ADDR.
    0008    8 Signed       4 IORFPNT        POINTER TO NEXT QUEUED IORBK
    000C   12 Signed       4 IORBPNT        POINTER TO PREVIOUS QUEUED IORBK
    0010   16 Signed       4 IORDISPN (0)   DISPATCHING FLAGS
    0010   16 Bitstring    1 IORQSTAT       DISPATCHING QUEUING STATUS
              1... ....      IORQQUED       X'80' WAITING AFTER STARTING I/O
              ..1. ....      IORQDSP        X'20' DISPATCHER HAS CONTROL OF
                                            IORBK
              ...1 ....      IORACT         X'10' ACTIVE I/O
              .... ...1      IORQANCH       X'01' CHANNEL SCHEDULING QUEUE
                                            (ANCHOR)
    0011   17 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
    0012   18 Bitstring    1 IORSCHED       SCHEDULING, UNSTACK CONTROL FLAGS
              1... ....      IORHIPRI       X'80' REQUEST TO GRANT A VERY
                                            HIGH DISPATCHER/SCHEDULER
                                            PRIORITY FOR THE VMDBK IDENTIFIED
                                            BY IORUSER
              .1.. ....      IORUCALL       X'40' UNSTACK IORBK WITH
                                            CALL-LINKAGE WHEN UNSTACKED BY
                                            THE DISPATCHER
              ..1. ....      IORFULLR       X'20' Target IRA is a fullreg
                                            entry point.
              .... ...1      IORIDTRQ       X'01' TRQBK IDENTIFIER (1=TRQBK,
                                            0=IORBK)
    0013   19 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
    0014   20 Signed       4 *              RESERVED FOR FUTURE IBM USE
    0018   24 Signed       4 IORSAVE        LOCATION TO SAVE R13 FOR IORSYN
                                            HCPPAG USES THIS FIELD AS THE
                                            POINTER IN A SINGLY LINKED LIST
                                            OF IORBKS. HCPCPH USES THIS FIELD
                                            AS THE POINTER TO A HLTBLK.
                                            HCPCPH WILL RESTORE THIS FIELD TO
                                            ITS ORIGINAL VALUE WHEN HALT
                                            PROCESSING IS COMPLETE.
    001C   28 Signed       4 IORPIOR        PENDING INTERRUPTION LIST
    0020   32 Signed       4 IORTASK        ADDRESS OF RCWTASK/CONTASK CHAIN
    0024   36 Signed       4 IORRDFND       ADDR OF 3270 FULL SCREEN READ
    0028   40 Signed       2 IORTYGBL       E.R.P. GLOBAL RETRY COUNT
              00000801       IORMXGCT       2049 MAXIMUM GLOBAL RETRY COUNT
    002A   42 Signed       2 IORTYLCL       E.R.P. LOCAL RETRY COUNT
    002C   44 Signed       2 IORECLVL       E.R.P. RECURSION LEVEL
              0000000A       IORMXRCT       10 MAXIMUM RECURSIVE COUNT
    002E   46 Signed       2 IORETCOD       E.R.P. COMPLETION CODE
              00000000       IORRCOK        0 SUCCESSFUL COMPLETION
              00000004       IORRCDRV       4 REDRIVE / RESUME
              00000008       IORRCEOF       8 END-OF-FILE
              0000000C       IORRCFTL       12 FATAL I/O COMPLETION
              00000010       IORRCKIL       16 SEVERE I/O ERROR
              00000014       IORRCNCL       20 I/O CANCELLED
    0030   48 Signed       4 IORVDEV        ADDRESS OF VIRTUAL DEVICE BLOCK
         OPERATION REQUEST BLOCK
    0034   52 Bitstring   32 IORORB (0)     OPERATION REQUEST BLOCK
    0034   52 Signed       4 IORRDEV        ADDRESS OF REAL DEVICE BLOCK
                                            (PARM)
    0038   56 Signed       4 IOROCTL (0)    FOLLOWING ARE CONTROL FIELDS
    0038   56 Bitstring    2 IOROKF (0)     KEY AND FLAG BYTES
    0038   56 Bitstring    1 IOROKEY        KEY PLUS 4 REQUIRED ZEROS
    0039   57 Bitstring    1 IOROFPI        FETCH, PROTECT AND INITIAL STATUS
    003A   58 Bitstring    1 IOROLPM        LOGICAL PATH MASK
    003B   59 Bitstring    1 IOROORB7       BYTE 7 OF SYSTEM ORB
    003C   60 Signed       4 IORCCWS (0)    FIRST CHANNEL COMMAND WORD
    003C   60 Signed       4 IORCPA         CHANNEL PROGRAM ADDRESS
    0040   64 Bitstring   20 IORXOWDS (0)   Extended portion of the ORB
    0040   64 Signed       4 IOROWRD3 (0)   ORB word 3
    0040   64 Bitstring    1 IORPRTY        I/O priority for channel
                                            subsystem
    0041   65 Bitstring    1 IOROW3B1       ORB word 3 byte 1
    0042   66 Bitstring    1 IOROW3B2       ORB word 3 byte 2
    0043   67 Bitstring    1 IOROW3B3       ORB word 3 byte 3
    0044   68 Signed       4 *              Reserved for future hardware use
    0048   72 Signed       4 *              Reserved for future hardware use
    004C   76 Signed       4 *              Reserved for future hardware use
    0050   80 Signed       4 *              Reserved for future hardware use
         VIRTUAL MACHINE'S ORB CONTROLS
    0054   84 Signed       4 IORUCTL (0)    SAVED GUEST CONTROL FIELD VALUES
    0054   84 Bitstring    2 IORUKF (0)     KEY AND FLAG BYTES
    0054   84 Bitstring    1 IORUKEY        KEY PLUS 4 REQUIRED ZEROS
    0055   85 Bitstring    1 IORUFPI        FETCH, PROTECT AND INITIAL STATUS
    0056   86 Bitstring    1 IORULPM        LOGICAL PATH MASK
    0057   87 Bitstring    1 IORUORB7       BYTE 7 OF GUEST ORB
    0058   88 Signed       4 *              Reserved for IBM use
    005C   92 Signed       4 IORPOSCT       MONITOR DASD ACCESS ARM
                                            POSITIONING COUNT- number of
                                            SEEKS or LOCATEs in the channel
                                            program. Valid when IORDPOSD is
                                            ON.
    0060   96 Signed       4 IORPOSSM       MONITOR DASD ARM MOTION -
                                            distance between first and last
                                            seek or locate in the channel
                                            program in terms of cylinders.
                                            Valid when IORDPOSD is ON.
    0064  100 Signed       4 *              Reserved for IBM use
         INTERRUPT RESPONSE BLOCK
    0068  104 Bitstring   96 IORIRB (0)     INTERRUPTION RESPONSE BLOCK
    0068  104 Bitstring   12 IORSCSW (0)    SUBCHANNEL CSW AREA
    0068  104 Bitstring    2 IORSCTLS (0)   SUBCHANNEL CSW CONTROLS
    0068  104 Bitstring    1 IORSKEY        SCSW KEY, LOGOUT, COND CODE
    0069  105 Bitstring    1 IORFPIZN       CCW CONTROLS & INITIAL RESPONSES
    006A  106 Bitstring    2 IORFCAC (0)    FUNCTION AND ACTIVITY BYTES
    006A  106 Bitstring    1 IORFCTL        FUNCTION CONTROL BYTE
    006B  107 Bitstring    1 IORACTL        ACTIVITY CONTROL PART
    006C  108 Bitstring    8 IORCASC (0)    COMBINED CCW ADDRESS, DEVICE
                                            STATUS, SUBCHANNEL STATUS, AND
                                            RESIDUAL COUNT FIELDS
    006C  108 Signed       4 IORCCWA        SCSW CHANNEL CMD WORD ADDR
    0070  112 Bitstring    4 IORCSC (0)     COMBINED DEVICE STATUS,
                                            SUBCHANNEL STATUS, AND RESIDUAL
                                            COUNT FIELDS
    0070  112 Bitstring    2 IORSTFLG (0)   STATUS FLAG FIELDS TOGETHER
    0070  112 Bitstring    1 IORDVST        SCSW DEVICE STATUS BITS
    0071  113 Bitstring    1 IORSCST        SCSW SUBCHANNEL STATUS BITS
    0072  114 Signed       2 IORCNT         SCSW RESIDUAL CCW DATA COUNT
    0074  116 Signed       4 IORIRLG (0)    LIMITED SUBCHANNEL LOGOUT WORD
    0074  116 Bitstring    1 IORDETCT (0)   S/370 ERROR DETECT FIELD
    0074  116 Bitstring    1 IORECF         ERROR CHECK FLAGS
    0075  117 Bitstring    1 IORSOURC (0)   S/370 ERROR SOURCE FIELD
    0075  117 Bitstring    1 IORLPUM        LAST PATH USED
    0076  118 Signed       2 IORDCTI (0)    DEVICE CONNECT TIME
    0076  118 Bitstring    1 IORFVF         FIELD VALIDITY FLAGS
    0077  119 Bitstring    1 IORTMSEQ       TERMINATION AND SEQUENCE CODES
    0078  120 Signed       4 IORERW (0)     EXTENDED REPORT WORD
    0078  120 Bitstring    1 IORERWB0       EXTENDED REPORT WORD, BYTE 0
    0079  121 Bitstring    1 IORERWB1       Extended Report Word, Byte 1
    007A  122 Bitstring    1 IORERWB2       Extended Report Word, Byte 2
    007B  123 Bitstring    1 IORERWB3       Extended Report Word, Byte 3
    007C  124 Bitstring    8 IORFSA64 (0)   64 bit failing storage address
    007C  124 Signed       4 IORFSA         Failing-Storage Address
    0080  128 Signed       4 *              RESERVED FOR FUTURE HARDWARE USE
    0084  132 Signed       4 IOR2DCCW       Secondary CCW address
    0088  136 Bitstring   32 IORXTLOG       I/O EXTENDED LOGOUT AREA
    00A8  168 Bitstring   32 IORXMEAS (0)   Extended Measurement Word
    00A8  168 Signed       4 IORXCNTI       Device-Connect Time
    00AC  172 Signed       4 IORXFPTI       Function-Pending Time
    00B0  176 Signed       4 IORXDDTI       Device-Disconnect Time
    00B4  180 Signed       4 IORXCQTI       Control-Unit-Queuing Time
    00B8  184 Signed       4 IORXDATI       Device-Active-Only Time
    00BC  188 Signed       4 IORXDBTI       Device-Busy Time
    00C0  192 Signed       4 IORXIRTI       Initial-Command-Response Time
    00C4  196 Signed       4 *              Reserved for future IBM use
    00C8  200 Bitstring   64 IORSCMSV       SCMBK save area
    0108  264 Signed       2 IORECYL        LAST CYLINDER USED IN CHANNEL
                                            PROGRAM Valid when IORDPOSD is
                                            turned on.
    010A  266 Bitstring    6 IORSEEK (0)    BBCCHH FOR COUNT-KEY-DATA
    010A  266 Bitstring    4 IORSBBCC (0)   BIN AND CYLINDER FOR
                                            COUNT-KEY-DATA
    010A  266 Signed       2 IORBIN         BIN NUMBER FOR COUNT-KEY-DATA
    010C  268 Signed       2 IORCYL         CYLINDER NUMBER FOR
                                            COUNT-KEY-DATA Valid when
                                            IORDPOSD is turned on.
    010E  270 Signed       2 IORHEAD        HEAD NUMBER FOR COUNT-KEY-DATA
    0110  272 Dbl-Word     8 IORSKCCW (0)   PRELIMINARY SEEK TO BE EXECUTED
    0110  272 Dbl-Word     8 IORSCCW (0)    SENSE CCW TO BE EXECUTED
    0110  272 Bitstring    1 IORCCWOC       CCW OPCODE
    0111  273 Bitstring    1 *              CCW FLAG BYTE
    0112  274 Signed       2 IORSCNT        CCW COUNT FIELD / SENSE BYTE
                                            COUNT
    0114  276 Signed       4 *              CCW ADDRESS FIELD
    0118  280 Signed       4 IOREXTN        POINTER TO EXTENSION DATA
    011C  284 Signed       4 *              Reserved for IBM use
    0120  288 Signed       4 IORRCTL (0)    CONTROLS PRESERVED FOR CHANNEL
                                            PROGRAM RESUMPTION (EXCEPT CFLG)
    0120  288 Signed       2 IORCCTL (0)    CONTROLS PRESERVED FOR CHANNEL
                                            PROGRAM CONTINUATION
    0120  288 Bitstring    1 IORIFLG        SPECIAL INFORMATION BLOCK
              1... ....      IORCONT        X'80' CHANNEL PROGRAM
                                            CONTINUATION
              .1.. ....      IORMDLCK       X'40' MINI-DISK LOCK HELD FOR
                                            THIS REQUEST
              ..1. ....      IORTRTRM       X'20' TRACE CCW'S FOR TERMINAL
                                            OUTPUT
              ...1 ....      IORTRPRT       X'10' TRACE CCW'S FOR PRINTER
                                            OUTPUT
              ..11 ....      IORTRCCW       IORTRTRM+IORTRPRT TRACE CCW'S FOR
                                            THIS OPERAT'N
              .... 1...      IORRESUM       X'08' CHANNEL PROGRAM RESUMPTION
              .... .1..      IORVXA         X'04' VIRTUAL XA GUEST I/O
                                            REQUEST
              .... ..1.      IORDPOSD       X'02' MONITOR SEEK DATA IS VALID
                                            IORDPOSD validates that IORCYL,
                                            IORECYL, IORPOSCT, IORPOSSM, and
                                            IORDWRIT were filled in when the
                                            channel program was built.
              .... ...1      IORDWRIT       X'01' DASD WRITE OPERATION
                                            Indicates channel program is
                                            write-only OR mixed read/write.
                                            Valid when IORDPOSD is turned on.
    0121  289 Bitstring    1 IORRFLG        I/O REQUEST CONTROL FLAGS
              1... ....      IORSYNCH       X'80' SYNCHRONOUS. MERGE
                                            SOLICITED STS. IORBK WILL NOT BE
                                            DISPATCHED UNTIL ALL SOLICITED
                                            STATUS IS RECIEVED.
              .1.. ....      IORDQUNS       X'40' DEQUEUE WITH UNSOLICITED
                                            STATUS. IF UNSOLICITED STATUS IS
                                            RECIEVED WHILE THIS IORBK IS
                                            START-PENDING OR ENQUEUED ON A
                                            REAL DEVICE, THE UNSOLICITED
                                            STATUS WILL BECOME THE COMPLETION
                                            STATUS FOR THIS IORBK. THIS DOES
                                            NOT APPLY TO UNSOLICITED
                                            ATTENTION FROM A CTCA. ATTENTION
                                            + BUSY FROM A CTCA IS SOLICITED
                                            WHEN THE SENSE DATA INDICATES
                                            THAT THE COMMANDS ON THE TWO
                                            SIDES OF THE ADAPTOR ARE
                                            CONFLICTING. WHEN THEY ARE NOT
                                            CONFLICTING, THE STATUS IS SIMPLY
                                            DISCARDED.
              ..1. ....      IORERPEQ       X'20' DETECT EQUIPMENT CHECKS
                                            WHICH MAY AFFECT OTHER I/O
                                            REQUESTS FOR THE SAME REAL
                                            DEVICE.
              ...1 ....      IORERPCP       X'10' PERFORM FULL CP I/O ERROR
                                            RECOVERY.
              .... 1...      IORERPNW       X'08' IF REAL DEVICE IS
                                            NOT-READY, DON'T WAIT FOR IT TO
                                            BECOME READY.
              .... .1..      IORUSRIO       X'04' USER (AS OPPOSED TO CP) IO
                                            OPERATION
              .... ..1.      IORHSCH0       X'02' GENERATE NON-FINAL IORBK
                                            FOR CC 0 FROM HOST
                                            HALT-SUBCHANNEL.
              .... ...1      IORDIAG        X'01' GUEST DIAGNOSE INTERFACE
                                            CCWS
    0122  290 Bitstring    1 IORCFLG        I/O REQUEST COMPLETION FLAGS
              1... ....      IORUNSL        X'80' UNSOLICITED STATUS
              .1.. ....      IORCOPY        X'40' NON-FINAL SOLICITED STATUS
              ..1. ....      IORCCWTR       X'20' CCW TRANSLATION PERFORMED
              ...1 ....      IORNOERP       X'10' ERP INVOCATION NOT ALLOWED
                                            TO PREVENT ERP RECURSION
              .... 1...      IORFTRAN       X'08' Channel program translated
                                            by HCPFTRAN (fast CCW translate)
              .... .1..      IORFATL        X'04' UNRECOVERABLE I/O ERROR
              .... ..1.      IORERDAS       X'02' CALLED FOR DASDI ERRORS
              .... ...1      IORDIA98       X'01' DIAGNOSE X'98' CCW
                                            TRANSLATION
    0123  291 Bitstring    1 IORCMD         COMMAND FIELD
              00000001       IORSTART       001 START REQUEST - ORB AT IORORB
              00000002       IORHALT        002 HALT REQUEST - CSWRESPN SET
                                            IN IOROFPI TO REQUEST A NON-FINAL
                                            IORBK WHEN CC 0 RECEIVED FOR HSCH
                                            INSTRUCTION.
              00000003       IORHALTD       003 HALTED START REQUEST
              00000004       IORCLEAR       004 CLEAR REQUEST
              00000005       IORMODFY       005 MODIFY REQUEST
              00000006       IORCANCL       006 CANCEL REQUEST
    0124  292 Bitstring    1 IORSTAT        I/O REQUEST STATUS FLAGS
              1... ....      IORSNSRQ       X'80' SENSE WILL BE REQUIRED
              .1.. ....      IORSNSAC       X'40' SENSE CURRENTLY ACTIVE ON
                                            DEVICE
              ..1. ....      IORSNSIV       X'20' SENSE INFORMATION WILL BE
                                            INVALID
              ...1 ....      IORSNS         X'10' VALID SENSE INFORMATION
                                            PRESENT
              .... 1...      IORCSNAV       X'08' CONCURRENT SENSE DATA IS
                                            ALREADY AVAILABLE
              .... .1..      IOR9C00        X'04' SIO OPERATION
              .... ..1.      IORSIFCC       X'02' ADD INTERFACE CONTROL
                                            CHECK. A MISSING INTERRUPT WAS
                                            DETECTED OR THE DEVICE PRESENTED
                                            INVALID STATUS (ALERT THE USER SO
                                            THE DEVICE WILL BE FIXED)
              .... ...1      IORMBUPD       X'01' GUEST MEASUREMENT BLOCK
                                            UPDATED
    0125  293 Bitstring    1 IORLMSGF       CFLF Inline Message flag byte
              1... ....      IORLFPSF       X'80' CFLF PSF CCW Simulation
                                            active
              .1.. ....      IORLFRLD       X'40' CFLF Lock Data queued
              ..1. ....      IORLFRID       X'20' CFLF User ID Data queued
              ...1 ....      IORLFATN       X'10' CFLF Attention Message
                                            queued
              .... 1...      IORLFRAD       X'08' CFLF Allocation data queued
              .... .1..      IORLFSSM       X'04' CFLF SSM CCW Simulation
                                            active
    0126  294 Bitstring    1 IORDFLGS       General I/O Flags
              1... ....      IORD254        X'80' Diagnose 254 I/O request
              .1.. ....      IORDSIC        X'40' Diagnose knocked device out
                                            of SIC
              ..1. ....      IORDIFC        X'20' IFCC forced by IOSBS
              ...1 ....      IORCTRAN       X'10' HCPCTR did the CCW
                                            translation
              .... 1...      IORDCAN        X'08' Active Diagnose 254 request
                                            cancelled by HCPIOSCA
    0127  295 Address      1 IORTYPE        I/O OPERATION REQUEST TYPE
              00000000       IORSIO         000 START I/O
              000000FE       IORCUSER       254 CHANGE IORUSER TO "SYSTEM"
              000000FF       IORSPECL       255 INFORMATIONAL IORBK
    0128  296 Bitstring    1 IORXFLG        EXTENDED INFORMATION FLAG
              1... ....      IORCPSUS       X'80' SUSPENDED CHANNEL PROGRAM
              .1.. ....      IORLIFO        X'40' RECOVERY REQUEST - QUEUE IT
                                            LIFO
              ..1. ....      IORISAM        X'20' IORBK CONTAINS ISAM
                                            RCWTASKS
              ...1 ....      IORDISAB       X'10' IORBK CONTAINS DISABLE
                                            RCWTASK
              .... 1...      IORMALPM       X'08' I/O MAY AFFECT PATH MASK
                                            VALIDITY
              .... .1..      IORNOLPM       X'04' DISREGARD RDEVLPM ON SSCH'S
              .... ..1.      IORMSWSP       X'02' SPECIAL PROCESSING
              .... ...1      IORUNLOK       X'01' PAGES ARE NOT LOCKED
    0129  297 Bitstring    1 IORITFLG       INTERRUPT FLAG
              1... ....      IORFKBSY       X'80' DEVICE STATUS BUSY SET BY
                                            HCPIOS
              .1.. ....      IORTSS         X'40' IORBK used for simulation
                                            by HCPTSS
              ..1. ....      IORHDVA        X'20' ISTAT on HSCH should be
                                            handled, not discarded. This
                                            status is due to the HDV Assist.
              ...1 ....      IORTRASH       X'10' IORBK to be discarded
              .... 1...      IOR370AC       X'08' Vestigial status from a 370
                                            Accommo- dation I/O. Status has
                                            already been presented in a 370
                                            CSW but is being preserved for a
                                            possible TSCH
              .... .1..      IORABUSY       X'04' 370 Accommodation busy. A
                                            condition which causes busy for
                                            370 but not for ESA/XC was
                                            detected. Show the Busy only in
                                            the 370 CSW.
              .... ..1.      IORNODQ        X'02' Prevents previously queued
                                            "non- flush" recovery I/O from
                                            being dequeued during flush ERP's
    012A  298 Bitstring    1 IORTFLG        TERMINAL CONTROL FLAG
              1... ....      IORCLSCR       X'80' CLEAR SCREEN & ISSUE FULL
                                            SCREEN I/O
    012B  299 Bitstring    1 IORSWCC        WCC CHARACTER
              .... ...1      IORCSENQ       X'01' REQUEST ENQUEUED ON
                                            RDEVBLOK
              .... ..1.      IORCSWAD       X'02' REQUEST WAITING FOR
                                            AVAILABLE DEV
              .... .1..      IORCSWBY       X'04' REQUEST WAITING FOR BUSY TO
                                            CLEAR
              .... 1...      IORCSTRU       X'08' REQUEST STARTED, NOT
                                            CONFIRMED
              ...1 ....      IORCSTRC       X'10' REQUEST STARTED, CONFIRMED
              ..1. ....      IORCSPCM       X'20' PARTIAL COMPLETION (CE OR
                                            PCI)
              .1.. ....      IORCSHLT       X'40' DEVICE HALTED PRIOR TO
                                            COMPLETION
              1... ....      IORCSFCM       X'80' FULL COMPLETION (SEE
                                            IORTTERM)
    012C  300 Bitstring    1 IORPFLG        PROCESSING FLAG
              1... ....      IORBKOUT       X'80' An end-user break-out
                                            occurred
              .1.. ....      IORIDONE       X'40' A break-out occurred after
                                            the I/O was complete
              ..1. ....      IORMULTI       X'20' This CP contains a
                                            multi-track CCW
              ...1 ....      IORWRKAL       X'10' WRKALLEG ON when I/O
                                            started
              .... 1...      IORPLV         X'08' MDC purge limits valid
              .... .1..      IORSCPQ        X'04' On state-change-pending
                                            queue
              .... ..1.      IORCIO         X'02' MDC I/O done on behalf of a
                                            guest channel program.
              .... ...1      IORUPVIO       X'01' Update virtual I/O request
                                            counters. Used by HCPIOV and
                                            HCPIOS to ensure that some
                                            counters are updated only once
                                            per guest start, regardless of
                                            the number of real starts done by
                                            CP.
    012D  301 Bitstring    1 IORCRCLC       Used for enable completion for
                                            dialled ASCII terminals
    012E  302 Bitstring    1 IORERMSG       ERROR MESSAGE CODE
              00000000       IORMREJ        000 COMMAND R  MESSAGE
              00000001       IORMIRQ        001 INTERVENTION REQUIRED MESSAGE
              00000002       IORMBUS        002 BUSOUT CHECK MESSAGE
              00000003       IORMEQP        003 EQUIPMENT CHECK MESSAGE
              00000004       IORMDTA        004 DATA CHECK MESSAGE
              00000005       IORMOVR        005 OVERRUN MESSAGE
              00000006       IORMTRK        006 TRACK CONDITION MESSAGE
              00000007       IORMSEK        007 SEEK CHECK MESSAGE
              00000008       IORMPRM        008 PERMANENT ERROR MESSAGE
              00000009       IORMTOV        009 TRACK OVERFLOW MESSAGE
              0000000A       IORMCNV        010 CONVERTOR CHECK MESSAGE
              0000000B       IORMCMP        011 COMPATIBILITY CHECK MESSAGE
              0000000C       IORMLDP        012 LOAD POINT MESSAGE
              0000000D       IORMPRT        013 PROTECTION CHECK MESSAGE
              0000000E       IORMNRF        014 NO RECORD FOUND MESSAGE
              0000000F       IORMEOC        015 END OF CYLINDER MESSAGE
              00000010       IORMBSN        016 BAD SENSE MESSAGE
              00000011       IORMUNK        017 UNKNOWN CCW MESSAGE
              00000012       IORMRCV        018 RECOVERY ERROR MESSAGE
              00000013       IORMPEB        019 PE BURST MESSAGE
              00000014       IORMCHN        020 CHANNEL ERROR MESSAGE
              00000015       IORMNDV        021 NO DEVICE MESSAGE
              00000016       IORMGAP        022 ERASE GAP ERROR MESSAGE
              00000017       IORMCTL        023 CONTROL CHECK MESSAGE
              00000018       IORMLDC        024 LOAD CHECK MESSAGE
              00000019       IORMFMT        025 FORMAT CHECK MESSAGE
              0000001A       IORDSEF        026 TAPE DATA SECURITY ERASE
                                            FAILED
              0000001B       IORMLST        027 LOST DATA MESSAGE
              0000001C       IORMTIM        028 TIME OUT MESSAGE
              0000001D       IORMPAR        029 PARITY CHECK MESSAGE
              0000001E       IORMUSP        030 UNIT SPECIFICATION
              0000001F       IORMDCK        031 DISPLAY CONTROL CHECK
              00000020       IORMOCK        032 OPERATION CHECK
              00000021       IORMEQPA       033 EQUPMENT CHECK WITH
                                            OPERATOR'S ACTION
              00000022       IORMUCS        034 UNUSUAL COMMAND SEQUENCE
              00000023       IORMOFF        035 DEVICE VARIED OFFLINE MESSAGE
              00000024       IORMWLB        036 DASD PACKED LABEL NOT MATCHED
              00000025       IORMELB        037 DASD LABEL CAN NOT BE READ
              00000026       IORMUNS        038 REPETITIVE UNSOLICITED DEVICE
                                            END
              00000027       IORMHDC        039 DASD POTENTIAL HEAD CRASH
              00000028       IORMSUP        040 COMMAND SUPPRESSION MESSSAGE
              0000002A       IORMINC        042 OPERATION INCOMPLETE
              00000057       IORMPEDP       087 MULTIPLE ENVIRONMENTAL DATA
                                            PRESENT
              0000005B       IORMCPRG       091 CHANNEL PROGRAM CHECK
              0000005F       IORMDLB        095 DASD LABEL DAMAGED
              000000EE       IORMBLFL       238 INDICATE BUFFER LOG FULL
              000000FE       IORMSGER       254 NON-CP (GUEST) ERROR
    012F  303 Bitstring    1 IORRFLGE       I/O REQUEST EXTENDED FLAG
              1... ....      IORVMISF       X'80' CSE CHANNEL PROGRAM, DO NOT
                                            RETRY
              .1.. ....      IORFABST       X'40' FABRICATE A STORE
                                            SUBCHANNEL (STSCH)
              ..1. ....      IORDSO1        X'20' First CCW is a DSO.
              ...1 ....      IORIOA         X'10' IOASSIST INTERRUPT
              .... 1...      IORHLTED       X'08' The I/O was halted by a
                                            function internal to HCPCNS. The
                                            IRA for the I/O should go
                                            directly to HALTIO to process the
                                            I/O completion.
              .... .1..      IORVCAN        X'04' Virtual Cancel Request
                                            Occurred
    0130  304 Bitstring   32 IORSDATA (0)   BUFFER FOR 32 BYTES OF SENSE DATA
    0130  304 Bitstring    1 IORSDB00       BYTE 0 OF SENSE DATA
    0131  305 Bitstring    1 IORSDB01       BYTE 1 OF SENSE DATA
    0132  306 Bitstring    1 IORSDB02       BYTE 2 OF SENSE DATA
    0133  307 Bitstring    1 IORSDB03       BYTE 3 OF SENSE DATA
    0134  308 Bitstring    1 IORSDB04       BYTE 4 OF SENSE DATA
    0135  309 Bitstring    1 IORSDB05       BYTE 5 OF SENSE DATA
    0136  310 Bitstring    1 IORSDB06       BYTE 6 OF SENSE DATA
    0137  311 Bitstring    1 IORSDB07       BYTE 7 OF SENSE DATA
    0138  312 Bitstring    1 IORSDB08       BYTE 8 OF SENSE DATA
    0139  313 Bitstring    1 IORSDB09       BYTE 9 OF SENSE DATA
    013A  314 Bitstring    1 IORSDB10       BYTE 10 OF SENSE DATA
    013B  315 Bitstring    1 IORSDB11       BYTE 11 OF SENSE DATA
    013C  316 Bitstring    1 IORSDB12       BYTE 12 OF SENSE DATA
    013D  317 Bitstring    1 IORSDB13       BYTE 13 OF SENSE DATA
    013E  318 Bitstring    1 IORSDB14       BYTE 14 OF SENSE DATA
    013F  319 Bitstring    1 IORSDB15       BYTE 15 OF SENSE DATA
    0140  320 Bitstring    1 IORSDB16       BYTE 16 OF SENSE DATA
    0141  321 Bitstring    1 IORSDB17       BYTE 17 OF SENSE DATA
    0142  322 Bitstring    1 IORSDB18       BYTE 18 OF SENSE DATA
    0143  323 Bitstring    1 IORSDB19       BYTE 19 OF SENSE DATA
    0144  324 Bitstring    1 IORSDB20       BYTE 20 OF SENSE DATA
    0145  325 Bitstring    1 IORSDB21       BYTE 21 OF SENSE DATA
    0146  326 Bitstring    1 IORSDB22       BYTE 22 OF SENSE DATA
    0147  327 Bitstring    1 IORSDB23       BYTE 23 OF SENSE DATA
    0148  328 Bitstring    1 IORSDB24       BYTE 24 OF SENSE DATA
    0149  329 Bitstring    1 IORSDB25       BYTE 25 OF SENSE DATA
    014A  330 Bitstring    1 IORSDB26       BYTE 26 OF SENSE DATA
    014B  331 Bitstring    1 IORSDB27       BYTE 27 OF SENSE DATA
    014C  332 Bitstring    1 IORSDB28       BYTE 28 OF SENSE DATA
    014D  333 Bitstring    1 IORSDB29       BYTE 29 OF SENSE DATA
    014E  334 Bitstring    1 IORSDB30       BYTE 30 OF SENSE DATA
    014F  335 Bitstring    1 IORSDB31       BYTE 31 OF SENSE DATA
    0150  336 Bitstring    1 IOREFLGS       General I/O Flags
              1... ....      IORASSH        X'80' Assign owned by another
                                            guest
              .1.. ....      IORNSNS        X'40' Don't do sense on channel
                                            program chk
              ..1. ....      IORALOK        X'20' Assign lock is held
              ...1 ....      IOROPCT        X'10' Out-prioritized count
                                            already updated
              .... 1...      IORPSFB        X'08' Tape PSF simulation had to
                                            backout
    0151  337 Bitstring    1 IORCPRI        Current priority of this I/O
                                            operation
    0152  338 Bitstring    2 IOROPTI        Times this segment has been
                                            out-prioritized
    0154  340 Bitstring    1 IOROPRI        Original priority of this I/O
                                            operation
    0155  341 Bitstring    3 *              Reserved for IBM use
    0158  344 Signed       4 IORLOWTA       Lowest track affected by I/O
    015C  348 Signed       4 IORHITA        Highest track affected by I/O
    0160  352 Address      4 IORPURGE       MDC purge block chain
    0164  356 Address      4 IORMIPTR       POINTER TO BLOCKS USED FOR
                                            HANDLING MISSING INTERRUPT
                                            CONDITIONS (HCPMIHDR)
    0168  360 Address      4 IORSUSND       ADDRESS OF ROUTINE TO ALLOW A
                                            SUSPENDED CHANNEL PROGRAM TO
                                            COMPLETE NOTE! ROUTINE IS CALLED
                                            BY STATIC LINKAGE ONLY
    016C  364 Signed       4 IORCPTCA       POINTER TO CHANNEL PROGRAM
                                            TRANSLATION COMMUNICATION AREA
    0170  368 Signed       4 IORMSGID       Message id
    0174  372 Signed       2 IORETRSN       Reason code for IORETCOD
         Only information that must be preserved for redrive processing may be
         added following this block comment.
              00000176       IORRDRVB       * IO REDRIVE FIELD BEGINNING
    0176  374 Bitstring    1 IORDFLG2       DASD FLAG 2
              1... ....      IORLREST       X'80' LOCATE RECORD EXTENDED
                                            TRANSLATED
              .1.. ....      IORSMRST       X'40' SUSPEND MULTIPATH
                                            RECONNECTION WAS TRANSLATED
              ..1. ....      IORMBSET       X'20' 'PREPARE FOR READ SUBSYSTEM
                                            DATA' CCW WITH SUBORDER OF
                                            MESSAGE BUFFER
              ...1 ....      IORCASET       X'10' 'PERFORM SUBSYSTEM
                                            FUNCTION' CCW WITH ORDER OF
                                            'CANCEL ASYNCH. FUNCTION'
              .... 1...      IORSKSV        X'08' SEEK ARGUMENT STORED BY
                                            ARMPS FROM A LOCATE RECORD OR
                                            SEEK
              .... .1..      IORRISET       X'04' A Read IPL CCW was
                                            translated
              .... ..1.      IORFLSET       X'02' A Locate CCW was translated
              .... ...1      IORCONCP       X'01' It's a CONCOPY channel
                                            program
    0177  375 Bitstring    1 IORPFLAG       DASD flags for redrive
              1... ....      IORVISET       X'80' Virtual I/O counter has
                                            been updated
              .1.. ....      IORVWSET       X'40' Virtual write I/O counter
                                            updated
              ..1. ....      IORPXUSD       X'20' Prefix CCW was translated
                                            and IORPREFX has valid data
              ...1 ....      IORPXSIM       X'10' Prefix CCW was simulated
              .... 1...      IORCPREF       X'08' CP has turned on the
                                            prefetch bit
                                            (IOROFPI/IORUFPI,CSWPREF) in the
                                            ORB (IORORB) for this guest I/O
                                            request.
    0178  376 Bitstring    4 IORPREFX (0)   Prefix CCW bytes 0-3
    0178  376 Bitstring    1 IORPXFMT       Prefix Format byte
    0179  377 Bitstring    1 IORPXVLD       Prefix Validity byte
              1... ....      IORPXDXV       X'80' Define Ext data valid
              .1.. ....      IORPXTSV       X'40' Time Stamp valid
              ..1. ....      IORPXVBA       X'20' Verify base address
    017A  378 Bitstring    1 IORPXBAA       Base address
    017B  379 Bitstring    1 IORPXAUX       Prefix Auxiliary byte
              1... ....      IORPXSMR       X'80' Suspend Multipath Reconnect
    017C  380 Bitstring   32 IORDEXNT       Define extent data
    019C  412 Signed       2 IORDEXDC       Define extent Data Count
    019E  414 Bitstring    1 IORDEXFG       Define extent CCW flags
              ..1. ....      IORDEXSL       X'20' Define extent sili bit
    019F  415 Bitstring    1 *              Reserved for future IBM use
    01A0  416 Bitstring    1 IORFMASK       SET FILE MASK DATA
         The IORDESET and IORGENDX bits in IORDFLG are used together to keep
         track of define extents within a guest channel program. Their meanings
         are defined as follows:
                   IORDESET   IORGENDX    MEANING
                      0          0        No define extent in
                                          channel program
                      0          1        (not defined)
                      1          0        Guest define extent in
                                          channel program
                      1          1        No guest define extent,
                                          only host-inserted one.
    01A1  417 Bitstring    1 IORDFLG        DASD FLAG
              1... ....      IORFMSET       X'80' FILE MASK CCW WAS
                                            TRANSLATED
              .1.. ....      IORDESET       X'40' DEFINE EXTENT CCW WAS
                                            TRANSLATED
              ..1. ....      IORSCSET       X'20' SPACE COUNT CCW WAS
                                            TRANSLATED
              ...1 ....      IORLRSET       X'10' LOCATE RECORD WAS
                                            TRANSLATED
              .... 1...      IORRASET       X'08' RESET ALLEGIENCE WAS
                                            SIMULATED
              .... .1..      IORSKSET       X'04' SEEK WAS SIMULATED
              .... ..1.      IORGCCWP       X'02' IORBK CONTAINS GLOBAL CCW
              .... ...1      IORGENDX       X'01' DEFINE EXTENT CCW WAS
                                            GENERATED TO BYPASS CU CACHE
    01A2  418 Bitstring    1 IORRLCMD       LAST EXECUTED REAL COMMAND CODE
    01A3  419 Bitstring    1 IORLRCNT       COUNT OF CCWS TRANSLATED AFTER A
                                            Locate Record or Locate CCW
    01A4  420 Bitstring    8 IORLCFBA (0)   Locate CCW parameter data
    01A4  420 Bitstring   24 IORLREC        Locate Record Data
    01BC  444 Bitstring    4 *              Reserved for IBM use
    01C0  448 Bitstring    4 IORSVW3        Save ORB Word 3
              0000004E       IORRDRSZ       (*-IORRDRVB) IORRDRV FIELD SIZE
                                            IN BYTES
              00000176       IORRDRV        IORRDRVB,IORRDRSZ IO REDRIVE
                                            FIELD
              00000039       IORSIZE        (*-IORBK+7)/8 IORBLOK BLOCK SIZE
         The following macro invocations are to ensure that an assembly error is
         generated if an increase, or decrease, in the size of the IORBK should
         have resulted in a change to the number of MVC or XC instructions
         generated by the HCPIORCC macro.
              00000040       IORMAX         512/8 The maximum number of
                                            doublewords that can be handled
                                            by two MVC or XC instructions.
              00000020       IORMIN         256/8 The minimum number of
                                            doublewords that can be handled
                                            by one MVC or XC instructions.
    0034   52 Signed       4 IORDEVIB (0)   SCHIB LOCATION FOR STSCH/MSCH
    0034   52 Bitstring   52 IORSCHIB       AREA TO COLLECT A SCHIB
    00C8  200 Signed       4 IORSCMBK (0)   OVERLAY FOR MEASUREMENT INFO
    00C8  200 Signed       4 IORNSSCH       INITIAL/DELTA SSCH OR RSCH COUNT
    00CC  204 Signed       4 IORNSAMP       INITIAL/DELTA SAMPLE COUNT
    00D0  208 Signed       4 IORCNTIM       INITIAL/DELTA DEVICE-CONNECT TIME
    00D4  212 Signed       4 IORFPTIM       INITIAL/DELTA FUNCTION-PENDING
                                            TIME
    00D8  216 Signed       4 IORDDTIM       INITIAL/DELTA DEVICE-DISCONNECT
                                            TIME
    00DC  220 Signed       4 IORCQTIM       INITIAL/DELTA
                                            CONTROL-UNIT-QUEUEING TIME
    00E0  224 Signed       4 IORDATIM       Device-Active-Only Time
    00E4  228 Signed       4 IORDBTIM       Device-Busy Time
    00E8  232 Signed       4 IORIRTIM       Initial-Command-Response Time
    00EC  236 Signed       4 * (7)          Not used
         Definitions of Reason Codes (IORETRSN) for different return codes
         (IORETCOD):
         IORFRESN - Fatal reason code (IORETCOD = 12) IORCRESN - Cancel reason
         code (IORETCOD = 20)
         NOTES : All non-zero reason codes should be unique regardless of the
         return code. This is because the return code may change without the
         reason code being updated, which could lead to a misinterpretation of
         the residual reason code if duplicates were defined.
    0174  372 Signed       2 IORFRESN       Reason code for IORETCOD = fatal
              00000000       IORFOK         0 Fatal with no special
                                            processing
              00000004       IORFSCP        4 Fatal due to
                                            state-change-pending
    0174  372 Signed       2 IORCRESN       Reason code for IORETCOD =
                                            cancelled
              00000000       IORCNLST       0 Cancelled after being started
              00000008       IORCNLSP       8 Cancelled before being started,
                                            i.e. the subchannel was start
                                            pending
    010A  266 Bitstring    4 IORPSFA        PSF CCW ADDRESS
    0068  104 Bitstring    1 IORDKEY        TYPE 1 Subchannel CRQBK Storage
                                            Key
    0069  105 Bitstring    1 *              Reserve
    006A  106 Bitstring    2 IORDFASC (0)   FCTL (BIT 17-19) ACTL (BIT 20-26)
    006A  106 Bitstring    1 IORDFCTL
    006B  107 Bitstring    1 IORDACTL
    006C  108 Bitstring    4 IORDCRQ        CRQBK address
    0070  112 Bitstring    1 *
    0071  113 Bitstring    1 IORDSC         TYPE 1 Status Control
    0072  114 Bitstring    2 *

#### IORBK Storage Layout

    *** IORBK - I/O Request and Response Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         IORUSER           |          IORIRA           |
    *     +---------------------------+---------------------------+
    *   8 |         IORFPNT           |         IORBPNT           |
    *     +------+------+------+------+---------------------------+
    *  10 |:QSTAT|//////|:SCHED|//////|///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  18 |         IORSAVE           |         IORPIOR           |
    *     +---------------------------+---------------------------+
    *  20 |         IORTASK           |         IORRDFND          |
    *     +-------------+-------------+-------------+-------------+
    *  28 |  IORTYGBL   |  IORTYLCL   |  IORECLVL   |  IORETCOD   |
    *     +-------------+-------------+-------------+-------------+
    *  30 |         IORVDEV           |         IORRDEV           |
    *     +------+------+------+------+---------------------------+
    *  38 |:OKEY |:OFPI |:OLPM |:OORB7|          IORCPA           |
    *     +------+------+------+------+---------------------------+
    *  40 |:PRTY |:OW3B1|:OW3B2|:OW3B3|///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  48 |///////////////////////////|///////////////////////////|
    *     +---------------------------+------+------+------+------+
    *  50 |///////////////////////////|:UKEY |:UFPI |:ULPM |:UORB7|
    *     +---------------------------+------+------+------+------+
    *  58 |///////////////////////////|         IORPOSCT          |
    *     +---------------------------+---------------------------+
    *  60 |         IORPOSSM          |///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  68 |:SKEY |:FPIZN|:FCTL |:ACTL |         IORCCWA           |
    *     +------+------+------+------+------+------+------+------+
    *  70 |:DVST |:SCST |   IORCNT    |IORECF|:LPUM |IORFVF|:TMSEQ|
    *     +------+------+------+------+------+------+------+------+
    *  78 |:ERWB0|:ERWB1|:ERWB2|:ERWB3|          IORFSA           |
    *     +------+------+------+------+---------------------------+
    *  80 |///////////////////////////|         IOR2DCCW          |
    *     +---------------------------+---------------------------+
    *  88 |                                                       |
    *     =                       IORXTLOG                        =
    *     |                                                       |
    *     +---------------------------+---------------------------+
    *  A8 |         IORXCNTI          |         IORXFPTI          |
    *     +---------------------------+---------------------------+
    *  B0 |         IORXDDTI          |         IORXCQTI          |
    *     +---------------------------+---------------------------+
    *  B8 |         IORXDATI          |         IORXDBTI          |
    *     +---------------------------+---------------------------+
    *  C0 |         IORXIRTI          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  C8 |                                                       |
    *     =                       IORSCMSV                        =
    *     |                                                       |
    *     +-------------+-------------+-------------+-------------+
    * 108 |  IORECYL    |   IORBIN    |   IORCYL    |  IORHEAD    |
    *     +------+------+-------------+-------------+-------------+
    * 110 |:CCWOC|//////|  IORSCNT    |///////////////////////////|
    *     +------+------+-------------+---------------------------+
    * 118 |         IOREXTN           |///////////////////////////|
    *     +------+------+------+------+------+------+------+------+
    * 120 |:IFLG |:RFLG |:CFLG |IORCMD|:STAT |:LMSGF|:DFLGS|:TYPE |
    *     +------+------+------+------+------+------+------+------+
    * 128 |:XFLG |:ITFLG|:TFLG |:SWCC |:PFLG |:CRCLC|:ERMSG|:RFLGE|
    *     +------+------+------+------+------+------+------+------+
    * 130 |:SDB00|:SDB01|:SDB02|:SDB03|:SDB04|:SDB05|:SDB06|:SDB07|
    *     +------+------+------+------+------+------+------+------+
    * 138 |:SDB08|:SDB09|:SDB10|:SDB11|:SDB12|:SDB13|:SDB14|:SDB15|
    *     +------+------+------+------+------+------+------+------+
    * 140 |:SDB16|:SDB17|:SDB18|:SDB19|:SDB20|:SDB21|:SDB22|:SDB23|
    *     +------+------+------+------+------+------+------+------+
    * 148 |:SDB24|:SDB25|:SDB26|:SDB27|:SDB28|:SDB29|:SDB30|:SDB31|
    *     +------+------+------+------+------+------+------+------+
    * 150 |:EFLGS|:CPRI |  IOROPTI    |:OPRI |////////////////////|
    *     +------+------+-------------+------+--------------------+
    * 158 |         IORLOWTA          |         IORHITA           |
    *     +---------------------------+---------------------------+
    * 160 |         IORPURGE          |         IORMIPTR          |
    *     +---------------------------+---------------------------+
    * 168 |         IORSUSND          |         IORCPTCA          |
    *     +---------------------------+-------------+------+------+
    * 170 |         IORMSGID          |  IORETRSN   |:DFLG2|:PFLAG|
    *     +------+------+------+------+-------------+------+------+
    * 178 |:PXFMT|:PXVLD|:PXBAA|:PXAUX|                           |
    *     +------+------+------+------+                           |
    * 180 |                                                       |
    *     =                       IORDEXNT                        =
    *     |                           +-------------+------+------+
    * 198 |                           |  IORDEXDC   |:DEXFG|//////|
    *     +------+------+------+------+-------------+------+------+
    * 1A0 |:FMASK|:DFLG |:RLCMD|:LRCNT|                           |
    *     +------+------+------+------+                           |
    * 1A8 |                                                       |
    *     =                       IORLREC                         =
    *     |                           +---------------------------+
    * 1B8 |                           |///////////////////////////|
    *     +---------------------------+---------------------------+
    * 1C0 |         IORSVW3           | 1C4
    *     +---------------------------+
    *
    *** IORBK - I/O Request and Response Block

    *** Overlay for IORORB in IORBK
    *
    *                                 +---------------------------+
    *     ...                      34 |                           |
    *     +---------------------------+                           |
    *  38 |                                                       |
    *     =                       IORSCHIB                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  68
    *
    *** Overlay for IORORB in IORBK

    *** Overlay for IORSCMSV in IORBK
    *
    *     +---------------------------+---------------------------+
    *  C8 |         IORNSSCH          |         IORNSAMP          |
    *     +---------------------------+---------------------------+
    *  D0 |         IORCNTIM          |         IORFPTIM          |
    *     +---------------------------+---------------------------+
    *  D8 |         IORDDTIM          |         IORCQTIM          |
    *     +---------------------------+---------------------------+
    *  E0 |         IORDATIM          |         IORDBTIM          |
    *     +---------------------------+---------------------------+
    *  E8 |         IORIRTIM          |///////////////////////////|
    *     +---------------------------+///////////////////////////|
    *  F0 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    * 108
    *
    *** Overlay for IORSCMSV in IORBK

    *** Overlay for IORETRSN in IORBK
    *
    *                                 +-------------+
    * 170 ...                     174 |  IORFRESN   | 176
    *                                 +-------------+
    *
    *** Overlay for IORETRSN in IORBK

    *** Overlay for IORETRSN in IORBK
    *
    *                                 +-------------+
    * 170 ...                     174 |  IORCRESN   | 176
    *                                 +-------------+
    *
    *** Overlay for IORETRSN in IORBK

    *** Overlay for IORSBBCC in IORBK
    *
    *                   +---------------------------+
    * 108 ...       10A |         IORPSFA           | 10E
    *                   +---------------------------+
    *
    *** Overlay for IORSBBCC in IORBK

    *** Overlay for IORSCSW in IORBK
    *
    *     +------+------+------+------+---------------------------+
    *  68 |:DKEY |//////|:DFCTL|:DACTL|         IORDCRQ           |
    *     +------+------+------+------+---------------------------+
    *  70 |//////|IORDSC|/////////////| 74
    *     +------+------+-------------+
    *
    *** Overlay for IORSCSW in IORBK

#### IORBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    IORABUSY       0129 04
    IORACT         0010 10
    IORACTL        006B
    IORALOK        0150 20
    IORASSH        0150 80
    IORBIN         010A
    IORBKOUT       012C 80
    IORBPNT        000C
    IORCANCL       0123 00000006
    IORCASC        006C
    IORCASET       0176 10
    IORCCTL        0120
    IORCCWA        006C
    IORCCWOC       0110
    IORCCWS        003C
    IORCCWTR       0122 20
    IORCFLG        0122
    IORCIO         012C 02
    IORCLEAR       0123 00000004
    IORCLSCR       012A 80
    IORCMD         0123
    IORCNLSP       0174 00000008
    IORCNLST       0174 00000000
    IORCNT         0072
    IORCNTIM       00D0
    IORCONCP       0176 01
    IORCONT        0120 80
    IORCOPY        0122 40
    IORCPA         003C
    IORCPREF       0177 08
    IORCPRI        0151
    IORCPSUS       0128 80
    IORCPTCA       016C
    IORCQTIM       00DC
    IORCRCLC       012D
    IORCRESN       0174
    IORCSC         0070
    IORCSENQ       012B 01
    IORCSFCM       012B 80
    IORCSHLT       012B 40
    IORCSNAV       0124 08
    IORCSPCM       012B 20
    IORCSTRC       012B 10
    IORCSTRU       012B 08
    IORCSWAD       012B 02
    IORCSWBY       012B 04
    IORCTRAN       0126 10
    IORCUSER       0127 000000FE
    IORCYL         010C
    IORDACTL       006B
    IORDATIM       00E0
    IORDBTIM       00E4
    IORDCAN        0126 08
    IORDCRQ        006C
    IORDCTI        0076
    IORDDTIM       00D8
    IORDESET       01A1 40
    IORDETCT       0074
    IORDEVIB       0034
    IORDEXDC       019C
    IORDEXFG       019E
    IORDEXNT       017C
    IORDEXSL       019E 20
    IORDFASC       006A
    IORDFCTL       006A
    IORDFLG        01A1
    IORDFLGS       0126
    IORDFLG2       0176
    IORDIAG        0121 01
    IORDIA98       0122 01
    IORDIFC        0126 20
    IORDISAB       0128 10
    IORDISPN       0010
    IORDKEY        0068
    IORDPOSD       0120 02
    IORDQUNS       0121 40
    IORDSC         0071
    IORDSEF        012E 0000001A
    IORDSIC        0126 40
    IORDSO1        012F 20
    IORDVST        0070
    IORDWRIT       0120 01
    IORD254        0126 80
    IORECF         0074
    IORECLVL       002C
    IORECYL        0108
    IOREFLGS       0150
    IORERDAS       0122 02
    IORERMSG       012E
    IORERPCP       0121 10
    IORERPEQ       0121 20
    IORERPNW       0121 08
    IORERW         0078
    IORERWB0       0078
    IORERWB1       0079
    IORERWB2       007A
    IORERWB3       007B
    IORETCOD       002E
    IORETRSN       0174
    IOREXTN        0118
    IORFABST       012F 40
    IORFATL        0122 04
    IORFCAC        006A
    IORFCTL        006A
    IORFKBSY       0129 80
    IORFLSET       0176 02
    IORFMASK       01A0
    IORFMSET       01A1 80
    IORFOK         0174 00000000
    IORFPIZN       0069
    IORFPNT        0008
    IORFPTIM       00D4
    IORFRESN       0174
    IORFSA         007C
    IORFSA64       007C
    IORFSCP        0174 00000004
    IORFTRAN       0122 08
    IORFULLR       0012 20
    IORFVF         0076
    IORGCCWP       01A1 02
    IORGENDX       01A1 01
    IORHALT        0123 00000002
    IORHALTD       0123 00000003
    IORHDVA        0129 20
    IORHEAD        010E
    IORHIPRI       0012 80
    IORHITA        015C
    IORHLTED       012F 08
    IORHSCH0       0121 02
    IORIDONE       012C 40
    IORIDTRQ       0012 01
    IORIFLG        0120
    IORIOA         012F 10
    IORIRA         0004
    IORIRB         0068
    IORIRLG        0074
    IORIRTIM       00E8
    IORISAM        0128 20
    IORITFLG       0129
    IORLCFBA       01A4
    IORLFATN       0125 10
    IORLFPSF       0125 80
    IORLFRAD       0125 08
    IORLFRID       0125 20
    IORLFRLD       0125 40
    IORLFSSM       0125 04
    IORLIFO        0128 40
    IORLMSGF       0125
    IORLOWTA       0158
    IORLPUM        0075
    IORLRCNT       01A3
    IORLREC        01A4
    IORLREST       0176 80
    IORLRSET       01A1 10
    IORMALPM       0128 08
    IORMAX         01C0 00000040
    IORMBLFL       012E 000000EE
    IORMBSET       0176 20
    IORMBSN        012E 00000010
    IORMBUPD       0124 01
    IORMBUS        012E 00000002
    IORMCHN        012E 00000014
    IORMCMP        012E 0000000B
    IORMCNV        012E 0000000A
    IORMCPRG       012E 0000005B
    IORMCTL        012E 00000017
    IORMDCK        012E 0000001F
    IORMDLB        012E 0000005F
    IORMDLCK       0120 40
    IORMDTA        012E 00000004
    IORMELB        012E 00000025
    IORMEOC        012E 0000000F
    IORMEQP        012E 00000003
    IORMEQPA       012E 00000021
    IORMFMT        012E 00000019
    IORMGAP        012E 00000016
    IORMHDC        012E 00000027
    IORMIN         01C0 00000020
    IORMINC        012E 0000002A
    IORMIPTR       0164
    IORMIRQ        012E 00000001
    IORMLDC        012E 00000018
    IORMLDP        012E 0000000C
    IORMLST        012E 0000001B
    IORMNDV        012E 00000015
    IORMNRF        012E 0000000E
    IORMOCK        012E 00000020
    IORMODFY       0123 00000005
    IORMOFF        012E 00000023
    IORMOVR        012E 00000005
    IORMPAR        012E 0000001D
    IORMPEB        012E 00000013
    IORMPEDP       012E 00000057
    IORMPRM        012E 00000008
    IORMPRT        012E 0000000D
    IORMRCV        012E 00000012
    IORMREJ        012E 00000000
    IORMSEK        012E 00000007
    IORMSGER       012E 000000FE
    IORMSGID       0170
    IORMSUP        012E 00000028
    IORMSWSP       0128 02
    IORMTIM        012E 0000001C
    IORMTOV        012E 00000009
    IORMTRK        012E 00000006
    IORMUCS        012E 00000022
    IORMULTI       012C 20
    IORMUNK        012E 00000011
    IORMUNS        012E 00000026
    IORMUSP        012E 0000001E
    IORMWLB        012E 00000024
    IORMXGCT       0028 00000801
    IORMXRCT       002C 0000000A
    IORNODQ        0129 02
    IORNOERP       0122 10
    IORNOLPM       0128 04
    IORNSAMP       00CC
    IORNSNS        0150 40
    IORNSSCH       00C8
    IOROCTL        0038
    IOROFPI        0039
    IOROKEY        0038
    IOROKF         0038
    IOROLPM        003A
    IOROORB7       003B
    IOROPCT        0150 10
    IOROPRI        0154
    IOROPTI        0152
    IORORB         0034
    IOROWRD3       0040
    IOROW3B1       0041
    IOROW3B2       0042
    IOROW3B3       0043
    IORPFLAG       0177
    IORPFLG        012C
    IORPIOR        001C
    IORPLV         012C 08
    IORPOSCT       005C
    IORPOSSM       0060
    IORPREFX       0178
    IORPRTY        0040
    IORPSFA        010A
    IORPSFB        0150 08
    IORPURGE       0160
    IORPXAUX       017B
    IORPXBAA       017A
    IORPXDXV       0179 80
    IORPXFMT       0178
    IORPXSIM       0177 10
    IORPXSMR       017B 80
    IORPXTSV       0179 40
    IORPXUSD       0177 20
    IORPXVBA       0179 20
    IORPXVLD       0179
    IORQANCH       0010 01
    IORQDSP        0010 20
    IORQQUED       0010 80
    IORQSTAT       0010
    IORRASET       01A1 08
    IORRCDRV       002E 00000004
    IORRCEOF       002E 00000008
    IORRCFTL       002E 0000000C
    IORRCKIL       002E 00000010
    IORRCNCL       002E 00000014
    IORRCOK        002E 00000000
    IORRCTL        0120
    IORRDEV        0034
    IORRDFND       0024
    IORRDRSZ       01C0 0000004E
    IORRDRV        01C0 00000176
    IORRDRVB       0174 00000176
    IORRESUM       0120 08
    IORRFLG        0121
    IORRFLGE       012F
    IORRISET       0176 04
    IORRLCMD       01A2
    IORSAVE        0018
    IORSBBCC       010A
    IORSCCW        0110
    IORSCHED       0012
    IORSCHIB       0034
    IORSCMBK       00C8
    IORSCMSV       00C8
    IORSCNT        0112
    IORSCPQ        012C 04
    IORSCSET       01A1 20
    IORSCST        0071
    IORSCSW        0068
    IORSCTLS       0068
    IORSDATA       0130
    IORSDB00       0130
    IORSDB01       0131
    IORSDB02       0132
    IORSDB03       0133
    IORSDB04       0134
    IORSDB05       0135
    IORSDB06       0136
    IORSDB07       0137
    IORSDB08       0138
    IORSDB09       0139
    IORSDB10       013A
    IORSDB11       013B
    IORSDB12       013C
    IORSDB13       013D
    IORSDB14       013E
    IORSDB15       013F
    IORSDB16       0140
    IORSDB17       0141
    IORSDB18       0142
    IORSDB19       0143
    IORSDB20       0144
    IORSDB21       0145
    IORSDB22       0146
    IORSDB23       0147
    IORSDB24       0148
    IORSDB25       0149
    IORSDB26       014A
    IORSDB27       014B
    IORSDB28       014C
    IORSDB29       014D
    IORSDB30       014E
    IORSDB31       014F
    IORSEEK        010A
    IORSIFCC       0124 02
    IORSIO         0127 00000000
    IORSIZE        01C0 00000039
    IORSKCCW       0110
    IORSKEY        0068
    IORSKSET       01A1 04
    IORSKSV        0176 08
    IORSMRST       0176 40
    IORSNS         0124 10
    IORSNSAC       0124 40
    IORSNSIV       0124 20
    IORSNSRQ       0124 80
    IORSOURC       0075
    IORSPECL       0127 000000FF
    IORSTART       0123 00000001
    IORSTAT        0124
    IORSTFLG       0070
    IORSUSND       0168
    IORSVW3        01C0
    IORSWCC        012B
    IORSYNCH       0121 80
    IORTASK        0020
    IORTFLG        012A
    IORTMSEQ       0077
    IORTRASH       0129 10
    IORTRCCW       0120 30
    IORTRPRT       0120 10
    IORTRTRM       0120 20
    IORTSS         0129 40
    IORTYGBL       0028
    IORTYLCL       002A
    IORTYPE        0127
    IORUCALL       0012 40
    IORUCTL        0054
    IORUFPI        0055
    IORUKEY        0054
    IORUKF         0054
    IORULPM        0056
    IORUNLOK       0128 01
    IORUNSL        0122 80
    IORUORB7       0057
    IORUPVIO       012C 01
    IORUSER        0000
    IORUSRIO       0121 04
    IORVCAN        012F 04
    IORVDEV        0030
    IORVISET       0177 80
    IORVMISF       012F 80
    IORVWSET       0177 40
    IORVXA         0120 04
    IORWRKAL       012C 10
    IORXCNTI       00A8
    IORXCQTI       00B4
    IORXDATI       00B8
    IORXDBTI       00BC
    IORXDDTI       00B0
    IORXFLG        0128
    IORXFPTI       00AC
    IORXIRTI       00C0
    IORXMEAS       00A8
    IORXOWDS       0040
    IORXTLOG       0088
    IOR2DCCW       0084
    IOR370AC       0129 08
    IOR9C00        0124 04

This information is based on z/VM V4R4.0. Last updated on 30 Jul 2003 at 13:01:49 EDT.
Copyright IBM Corporation, 1990, 2003