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

#### VDEV

Prolog

Control Block Contents
VDEV DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### VDEV Prolog

     NAME       : HCPVDEV
     DESCRIPTION: VIRTUAL DEVICE CONTROL BLOCK
     DSECT      : VDEV
     FUNCTION   : DESCRIBE THE STATUS OF AN I/O DEVICE (REAL OR VIRTUAL)
                  ACCESSABLE BY A VIRTUAL MACHINE.
     LOCATED BY - A POINTER IN THE LOWEST LEVEL INDEX VECTOR IN THE
                  FOUR-LEVEL TREE ANCHORED IN:
                    VMDCHRSN - FOR ACCESS VIA SUBCHANNEL NUMBER
                    VMDCHRDN - FOR ACCESS VIA DEVICE NUMBER
                  RDEVVDEV - DEDICATED DEVICE ONLY
                  BLKVDEVA - DEVICES CONNECTED TO DASD BLOCK I/O
                             SYSTEM SERVICE
                  VMDVSPRT - PRINTER TO USE IN DUMP, TRACE, ... CMDS
                  VMDVCONS - CONSOLE
                  MDIRVDEV - VDEV TO WHICH A MINI-DISK EXTENT IS
                             VIRTUALLY RESERVED.
                  WHILE AN I/O EVENT IS OUTSTANDING FOR A VIRTUAL
                  MACHINE, THE ADDRESS OF A VDEV MAY APPEAR IN:
                    CHCQUEUE(I) - FIRST DEVICE WITH AN INTERRUPT PENDING
                                  ON CHANNEL I (OR IN CHANNEL CLASS I)
                    VDEVFPNT - NEXT DEVICE WITH INTERRUPT PENDING ON
                               THIS CHANNEL (OR THIS VDEV, IF LAST)
                    VDEVBPNT - PREVIOUS INTERRUPT PENDING DEVICE ON THIS
                               CHANNEL (OR THIS VDEV, IF FIRST)
                    VMDWVDEV - DEVICE CAUSING I/O WAIT CONDITION
                               - SYNCHRONOUS I/O VIA DIAGNOSE 18 OR 20
                               - VIRTUAL MACHINE LOOPING ON TIO INSTR.
                    IORVDEV -  VDEV WITH WHICH VIRTUAL MACHINE'S I/O
                               REQUEST IS ASSOCIATED.
                  WHEN A GUEST REQUESTS AN ASYNCHRONOUS MESSAGE,
                  THE ADDRESS OF A VDEV MAY APPEAR IN:
                    AEBKVDEV - VDEV WITH WHICH VIRTUAL MACHINE'S
                               ASYNCHRONOUS MESSAGE REQUEST IS
                               ASSOCIATED.
                  I/O SUPERVISOR ROUTINES NORMALLY USE REGISTER 6 TO
                  ADDRESS THE VDEV ASSOCIATED WITH THE EVENT BEING
                  PROCESSED.
     CREATED BY : HCPVDB
     DELETED BY : HCPVDB

#### VDEV Control Block Content

#### VDEV DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      VDEV           VIRTUAL DEVICE CONTROL BLOCK
    0000    0 Signed       4 VDEVFPNT       Forward interruption pointer.
                                            Host logical address of a VDEV.
                                            Points to self if not enqueued.
    0004    4 Signed       4 VDEVBPNT       Backward interruption pointer.
                                            Host logical address of a VDEV.
                                            Points to self if not enqueued.
    0008    8 Dbl-Word     8 VDEVLOCK (0)   VIRTUAL DEVICE LOCKWORD
    0008    8 Address      4 VDEVLOWN       ADDRESS OF LOCK OWNER'S VMDBK
    000C   12 Address      4 VDEVTSKQ       ANCHOR FOR QUEUE OF WAITING TASKS
    0010   16 Signed       2 VDEVSUB        VIRTUAL SUBCHANNEL NUMBER
    0012   18 Signed       2 VDEVCODE (0)   VIRTUAL DEVICE IDENTITY CODE
    0012   18 Bitstring    1 VDEVCLAS       DEVICE CLASS
              1... ....      CLASTERM       X'80' CLASTERM TERMINAL DEVICE
                                            CLASS
              .1.. ....      CLASGRAF       X'40' CLASGRAF GRAPHIC DISPLAY
                                            DEVICE CLASS
              .1.. ...1      CLASGRFR       X'41' CLASGRFR GRAPHIC DISPLAY
                                            DEVICE CLASS (REMOTE)
              ..1. ....      CLASPOOL       X'20' CLASPOOL UNIT RECORD
                                            SPOOLING DEVICE CLASS
              ...1 ....      CLASSVCM       X'10' CLASSVCM SIMULATED DEVICE
                                            CLASS
              .... 1...      CLASTAPE       X'08' CLASTAPE MAGNETIC TAPE
                                            DEVICE CLASS
              .... .1..      CLASDASD       X'04' CLASDASD DIRECT ACCESS
                                            STORAGE DEVICE CLASS
              .... ..1.      CLASSPEC       X'02' CLASSPEC SPECIAL DEVICE
                                            CLASS
              .... ...1      CLASSWCH       X'01' CLASSWCH Switch device
                                            class
              1111 1111      CLASAIF        X'FF' CLASAIF
                                            Adapter-Interrupt-Facility (AIF)
                                            Class
    0013   19 Bitstring    1 VDEVTYPE       DEVICE TYPE
              1... ....      TYP2700        X'80' TYP2700 TERM - 2700 BISYNC
                                            LINE
              1... 1...      TYPBSC         X'88' TYPBSC TERM - BISYNC LINE
                                            FOR 3270 REMOTE STATION
              .1.. ....      TYPCONS        X'40' TYPCONS TERM - CONSOLE
                                            DEVICE
              .1.. ....      TYP3215        X'40' TYP3215 TERM - 3215 CONSOLE
              .1.. ....      TYP1052        X'40' TYP1052 TERM - 1052 CONSOLE
              ..1. ....      TYPTTY         X'20' TYPTTY TERM - USASCII-8
                                            TELEGRAPH TERMINAL
              ...1 ....      TYPIBM1        X'10' TYPIBM1 TERM - IBM TERMINAL
                                            CONTROL TYPE 1
              ...1 11..      TYPUNDEF       X'1C' TYPUNDEF TERM - TERMINAL
                                            TYPE UNDEFINED
              ...1 1...      TYP2741        X'18' TYP2741 TERM - 2741
                                            COMMUNICATIONS TERMINAL
              ...1 1...      TYP3767        X'18' TYP3767 TERM - 3767 IN 2741
                                            COMPATIBILITY MOD
              ...1 .1..      TYP1050        X'14' TYP1050 TERM - 1050
                                            COMMUNICATIONS TERMINAL
              .... 1...      TYPSDLC        X'08' TYPSDLC TERM - SDLC
                                            Integrated Adapter
              ..1. ....      TYPTELE2       X'20' TYPTELE2 TERM - TELE2
                                            Integrated Adapter
              ..1. .1..      TYPHDLC        X'24' TYPHDLC TERM - HDLC
                                            Integrated Adapter
              ..1. 1...      TYPILAN        X'28' TYPILAN TERM - ILAN
                                            Integrated Adapter
              ..1. 1...      TYPELAN        X'28' TYPELAN TERM - ELAN
                                            Integrated Adapter
              .1.. ....      TYP3270        X'40' TYP3270 GRAF - 3270 GENERIC
                                            DISPLAY STATION
              1... ....      TYP3277        X'80' TYP3277 GRAF - 3277 DISPLAY
                                            STATION
              .1.. ....      TYP3278        X'40' TYP3278 GRAF - 3278 DISPLAY
                                            STATION
              .1.. ....      TYP3178        X'40' TYP3178 GRAF - 3178 DISPLAY
                                            STATION
              .1.. ....      TYP3279        X'40' TYP3279 GRAF - 3279 DISPLAY
                                            STATION
              .1.. ....      TYP3179        X'40' TYP3179 GRAF - 3179 DISPLAY
                                            STATION
              .1.. ....      TYP3180        X'40' TYP3180 GRAF - 3180 DISPLAY
                                            STATION
              .1.. ....      TYP3290        X'40' TYP3290 GRAF - 3290 DISPLAY
                                            STATION
              .1.. ....      TYP3190        X'40' TYP3190 GRAF - 3190 DISPLAY
                                            STATION
              ..1. ....      TYP3271        X'20' TYP3271 GRAF - 3271
                                            CONTROLLER (REMOTE)
              ...1 ....      TYP3275        X'10' TYP3275 GRAF - 3275 DISPLAY
                                            STATION
              .... 1...      TYP3284        X'08' TYP3284 GRAF - 3284 PRINTER
              .... 1...      TYP3286        X'08' TYP3286 GRAF - 3286 PRINTER
              .... 1..1      TYP3287        X'09' TYP3287 GRAF - 3287 PRINTER
              .... 1...      TYP3288        X'08' TYP3288 GRAF - 3288 PRINTER
              .... 1..1      TYP3289        X'09' TYP3289 GRAF - 3289 PRINTER
              .... 1...      TYP3287L       X'08' TYP3287L GRAF - 3287
                                            LOGICAL PRINTER
              .... 1...      TYP3289L       X'08' TYP3289L GRAF - 3289
                                            LOGICAL PRINTER
              .... .1..      TYP2250        X'04' TYP2250 GRAF - 2250 DISPLAY
                                            UNIT
              .... .1..      TYP3250        X'04' TYP3250 GRAF - 3250 DISPLAY
                                            UNIT
              .... .11.      TYP5080        X'06' TYP5080 GRAF - 5080 DISPLAY
                                            UNIT
              ..11 ....      TYPCLUST       X'30' TYPCLUST GRAF - CLUSTER
                                            CTLR (3271 OR 3275)
              .... ..1.      TYPIC          X'02' TYPIC TERM - Integrated
                                            console GRAF - Integrated 3270
              1... ....      TYPRDR         X'80' TYPRDR SPOL - CARD READER
                                            DEVICE
              1... ...1      TYP2501        X'81' TYP2501 SPOL - 2501 CARD
                                            READER
              1... ..1.      TYP2540R       X'82' TYP2540R SPOL - 2540 CARD
                                            READER
              1... .1..      TYP3505        X'84' TYP3505 SPOL - 3505 CARD
                                            READER
              .1.. ....      TYPPUN         X'40' TYPPUN SPOL - CARD PUNCH
                                            DEVICE
              .1.. ..1.      TYP2540P       X'42' TYP2540P SPOL - 2540 CARD
                                            PUNCH
              .1.. .1..      TYP3525        X'44' TYP3525 SPOL - 3525 CARD
                                            PUNCH
              ..1. ....      TYPPRT         X'20' TYPPRT SPOL - PRINTER TYPE
                                            DEVICE
              ..1. ...1      TYP1403        X'21' TYP1403 SPOL - 1403 PRINTER
              ..1. ..1.      TYP32XX        X'22' TYP32XX SPOL - 3203 OR 3211
                                            PRINTER
              ..1. .11.      TYP3203        X'26' TYP3203 SPOL - 3203 PRINTER
              ..1. ..1.      TYP3211        X'22' TYP3211 SPOL - 3211 PRINTER
              ..1. 1...      TYP3800        X'28' TYP3800 SPOL - 3800 PRINTER
              ..1. ..11      TYP3262        X'23' TYP3262 SPOL - 3262 PRINTER
              ..1. .1..      TYP4245        X'24' TYP4245 SPOL - 4245 PRINTER
              ..1. 1..1      TYP4248        X'29' TYP4248 SPOL - 4248 PRINTER
              ..1. .1.1      TYP3820        X'25' TYP3820 SPOL - 3820 PRINTER
                                            - dedicated only
              ..1. .111      TYPAFP1        X'27' TYPAFP1 SPOL - AFP1 PRINTER
                                            - dedicated only
              ..1. 1.1.      TYPVAFP        X'2A' TYPVAFP SPOL - VAFP PRINTER
                                            - simulated only
              ...1 ....      TYPSYS         X'10' TYPSYS SPOL - SYSTEM VIRT
                                            DEVICE FOR DUMPS
              ...1 ....      TYP3420        X'10' TYP3420 TAPE - 3420 TAPE
                                            DRIVE
              ..1. ....      TYP3430        X'20' TYP3430 TAPE - 3430 TAPE
                                            DRIVE
              .1.. ....      TYP3480        X'40' TYP3480 TAPE - 3480 TAPE
                                            DRIVE
              .1.. ..1.      TYP3424        X'42' TYP3424 TAPE - 3424 TAPE
                                            DRIVE
              .1.. .1..      TYP9348        X'44' TYP9348 TAPE - 9348 TAPE
                                            DRIVE
              1... ....      TYP3422        X'80' TYP3422 TAPE - 3422 TAPE
                                            DRIVE
              1... ...1      TYP3490        X'81' TYP3490 TAPE - 3490 TAPE
                                            DRIVE
              1... ..11      TYP3590        X'83' TYP3590 TAPE - 3590 TAPE
                                            DRIVE
              .1.. ....      TYP3330        X'40' TYP3330 DASD - 3330 DISK
                                            STORAGE FACILITY
              ..1. ....      TYP3340        X'20' TYP3340 DASD - 3340 DISK
                                            STORAGE FACILITY
              ...1 ....      TYP3350        X'10' TYP3350 DASD - 3350 DISK
                                            STORAGE FACILITY
              ...1 ...1      TYP3350C       X'11' TYP3350C DASD - 3350 4 X 8
                                            PAGING STORAGE
              ...1 ..1.      TYP3350D       X'12' TYP3350D DASD - 3350 4 X 4
                                            PAGING STORAGE
              .... 1...      TYP2305        X'08' TYP2305 DASD - 2305 FIXED
                                            HEAD STORAGE FACILITY
              .... .1..      TYP3380        X'04' TYP3380 DASD - 3380 DISK
                                            STORAGE FACILITY
              1... ..1.      TYP3390        X'82' TYP3390 DASD - 3390 DISK
                                            STORAGE FACILITY
              1... ....      TYP3375        X'80' TYP3375 DASD - 3375 DISK
                                            STORAGE FACILITY
              .... ..1.      TYP3370        X'02' TYP3370 DASD - 3370 DISK
                                            STORAGE FACILITY
              1... ...1      TYP9345        X'81' TYP9345 DASD - 9345 DISK
                                            STORAGE FACILITY
              ..1. ...1      TYP9332        X'21' TYP9332 DASD - 9332 FBA
                                            Direct Access Storage
              ..1. ..1.      TYP9335        X'22' TYP9335 DASD - 9335 FBA
                                            Direct Access Storage
              ..1. .1..      TYP9336        X'24' TYP9336 DASD - 9336 FBA
                                            Direct Access Storage
              ..1. 1...      TYPFBA         X'28' TYPFBA DASD - Generic FBA
                                            DAS
              .1.. ....      TYP9033        X'40' TYP9033 SWCH - 9033 Switch
                                            device
              1... ....      TYP9032        X'80' TYP9032 SWCH - 9032 Switch
                                            device
              ..1. ....      TYP2032        X'20' TYP2032 SWCH - 2032 FICON
                                            Switch device
              1... ....      TYPCTCA        X'80' TYPCTCA SPEC - CHANNEL TO
                                            CHANNEL ADAPTER
              1... ....      TYP3088        X'80' TYP3088 SPEC - 3088
                                            MULTISYSTEM CHANNEL COMMUNICATION
                                            UNIT
              .1.. ....      TYP3704        X'40' TYP3704 SPEC - 3704
                                            PROGRAMMABLE COMMUNICATION
                                            CONTROL UNIT
              .1.. ....      TYP3705        X'40' TYP3705 SPEC - 3705
                                            PROGRAMMABLE COMMUNICATION
                                            CONTROL UNIT
              ..1. ....      TYPOSA         X'20' TYPOSA SPEC - Open Systems
                                            Adapter (OSA)
              ...1 ....      TYPFCP         X'10' TYPFCP SPEC - Open FCP
                                            Adapter (FCP)
              .... ..1.      TYP3851        X'02' TYP3851 SPEC - MSS MASS
                                            STORAGE COMMUNICATOR
              .... 1...      TYP3890        X'08' TYP3890 SPEC - 3890
                                            DOCUMENT PROCESSOR
              .... ..11      TYPALIAS       X'03' TYPALIAS SPEC - PAV Alias
              .... ...1      TYPUNSUP       X'01' TYPUNSUP SPEC - DEVICE
                                            UNSUPPORTED BY * THE VM/ 370
                                            MIGRATION AID
              .... ..1.      TYPDYNIO       X'02' TYPDYNIO VCM - Dynamic I/O
              .... ...1      TYPMSGF        X'01' TYPMSGF VCM - Message
                                            Facility
    0014   20 Signed       4 VDEVUSER       Host logical address of VMDBK of
                                            owner
    0018   24 Bitstring    1 VDEVSTAT       DEVICE STATUS - OWNED BY VIRTUAL
                                            I/O INSTRUCTION SIMULATION. THIS
                                            IS NOT TO BE USED BY VIRTUAL
                                            DEVICE SIMULA- TION.
              1... ....      VDEVBUSY       X'80' VDEVBUSY START FUNCTION
              .1.. ....      VDEVPRCE       X'40' VDEVPRCE CHANNEL END
                                            RECEIVED
              ..1. ....      VDEVCLRF       X'20' VDEVCLRF CLEAR FUNCTION
              ...1 ....      VDEVHLTF       X'10' VDEVHLTF HALT FUNCTION
              1111 ....      VDEVACTV       VDEVBUSY+VDEVPRCE+VDEVCLRF+VDEVHL
                                            TF VDEVACTV
              .... 1...      VDEVSUSP       X'08' VDEVSUSP SUBCHANNEL
                                            SUSPENDED
              .... .1..      VDEVRPND       X'04' VDEVRPND RESUME PENDING
              .... ..1.      VDEVQUED       X'02' VDEVQUED DEVICE-BUSY
                                            RECEIVED - VDEVNIOR CONTAINS THE
                                            ADDRESS OF AN IORBK WHICH
                                            RECEIVED AN INITIAL STATUS OF
                                            BUSY-ALONE AND IS AWAITING AN
                                            UNSOLICITED DEVICE END.
              .... ...1      VDEVCATT       X'01' VDEVCATT ATTACHED VIA
                                            CONSOLE COMMAND
    0019   25 Bitstring    1 VDEVWAIT       WAIT STATUS CONTROLS
              1... ....      VDEVIMRS       X'80' VDEVIMRS VM SUSPENDED
                                            PENDING I/O RESPONSE
              .1.. ....      VDEVWINT       X'40' VDEVWINT CPU(S) AWAITING
                                            STATUS (TIO/TSCH BUSY)
    001A   26 Bitstring    1 VDEVAFLG       DEVICE ALLOCATION FLAG
              1... ....      VDEVINTV       X'80' VDEVINTV SIMULATED
                                            INTERVENTION REQUIRED
              .1.. ....      VDEVTDSK       X'40' VDEVTDSK DEVICE IS DASD
                                            TDISK
              ..1. ....      VDEVVSIM       X'20' VDEVVSIM DEVICE IS
                                            SIMULATED BY VDSBK
              ...1 ....      VDEVFULL       X'10' VDEVFULL DEVICE IS A
                                            COMPLETE VOLUME
              .... 1...      VDEVDED        X'08' VDEVDED DEVICE IS ATTACHED
                                            TO VDEVRDEV
              .... .1..      VDEVMPLX       X'04' VDEVMPLX MULTIPLE EXPOSURE
                                            DEVICE
              .... ..1.      VDEVFPO        X'02' VDEVFPO THE DEVICE IS A
                                            FULL-PACK-OVERLAY MINIDISK
              .... ...1      VDEVDTCH       X'01' VDEVDTCH THE DEVICE IS
                                            BEING DETACHED
    001B   27 Bitstring    1 VDEVBFLG       HALT flags plus some misc flags
              1... ....      VDEVBCC0       X'80' VDEVBCC0 BACKUP CONFIRMED
                                            CC 0 FLAG
              .1.. ....      VDEVBPCI       X'40' VDEVBPCI BACKUP PCI FLAG
              ..1. ....      VDEVBSUI       X'20' VDEVBSUI BACKUP SUSPENSION
                                            INTERRUPT FLAG
              .... 1...      VDEVQACT       X'08' VDEVQACT BACKUP QDIO Active
                                            Status
              .... .1..      VDEVCMS        X'04' VDEVCMS Device is attached
                                            to adjunct
              .... ..1.      VDEVVMIO       X'02' VDEVVMIO Update VMDIOACT
                                            for active I/O
    001C   28 Bitstring    1 VDEVDFLG       DEVICE CONTROL FLAGS
              1... ....      VDEVRO         X'80' VDEVRO DEVICE- READ ONLY
                                            ACCESS
              .1.. ....      VDEVENAB       X'40' VDEVENAB COMMUNICATION LINE
                                            - ENABLED
              ..1. ....      VDEVDIAL       X'20' VDEVDIAL COMMUNICATION LINE
                                            - DIALED
              ...1 ....      VDEVSDIA       X'10' VDEVSDIA COMMUNICATION LINE
                                            - SNA DIALED
              .... 1...      VDEVNOTO       X'08' VDEVNOTO If on, means that
                                            this VDEV is no longer
                                            operational, because it is soon
                                            going away. Set by Detach
                                            processing.
              .... .1..      VDEVRSRL       X'04' VDEVRSRL RESERVE/RELEASE
                                            VALID CCW'S
              .... ..1.      VDEVNSEG       X'02' VDEVNSEG NO CHAN PROG
                                            SEGMENTATION ALLOWED
              .... ...1      VDEVGCWE       X'01' VDEVGCWE GLOBAL CCW
                                            EXPECTED FOR THIS DEVICE
    001D   29 Bitstring    1 VDEVCFLG       CONSOLE PROCESSING CONTROLS
              1... ....      VDEVINT3       X'80' VDEVINT3 Device used as
                                            integrated 3270
              .1.. ....      VDEVPPA1       X'40' VDEVPPA1 REFLECT PA1 KEY TO
                                            THE VIRTUAL MACHINE
              ..1. ....      VDEVGSUS       X'20' VDEVGSUS FULL SCREEN GUEST
                                            WAS SUSPENDED WITH UNIT
                                            EXCEPTION. CP MUST GENERATE AN
                                            UNSOLICITED DEVICE END TO RESUME
                                            GUEST
              ...1 ....      VDEVDING       X'10' VDEVDING dial in progress
              .... 1...      VDEVATTN       X'08' VDEVATTN ATTENTION
                                            INTERRUPT MUST BE GENERATED
              .... .1..      VDEVBRGS       X'04' VDEVBRGS Set RDEVGSUS when
                                            reconnected to console RDEV
    001E   30 Bitstring    1 VDEVFFLG       MINIDISK FLAGS
              1... ....      VDEVLNKS       X'80' VDEVLNKS STABLE MINIDISK
                                            LINK
              .1.. ....      VDEVLNKE       X'40' VDEVLNKE EXCLUSIVE MINIDISK
                                            LINK
              ..1. ....      VDEVDVFP       X'20' VDEVDVFP THE DEVICE IS A
                                            DEVNO DEFINED FULL-PACK MINIDISK
              ...1 ....      VDEVQDSK       X'10' VDEVQDSK The device is a
                                            VDISK
              .... 1...      VDEVFBA        X'08' VDEVFBA FBA disk or
                                            minidisk
              .... .1..      VDEVRMLF       X'04' VDEVRMLF Minidisk can use
                                            real MPLF facility
              .... ..1.      VDEVSULF       X'02' VDEVSULF Suppress CFLF and
                                            MPLF
              .... ...1      VDEV3DSK       X'01' VDEV3DSK VCM Vdisk
    001F   31 Bitstring    1 VDEVPFLG       DEVICE PROCESSING FLAG
              1... ....      VDEVCPCL       X'80' VDEVCPCL DEVICE CLOSED BY
                                            CP COMMAND
              .1.. ....      VDEVPURG       X'40' VDEVPURG DEVICE CLOSED AND
                                            PURGED BY CP COMMAND
              ..1. ....      VDEVNRSM       X'20' VDEVNRSM DEVICE CANNOT
                                            RESUME CHANNEL PROGRAM
              ...1 ....      VDEVDPRE       X'10' VDEVDPRE DYMAMIC PATHING
                                            HAS BEEN REQUESTED
              .... 1...      VDEVTRCW       X'08' VDEVTRCW FORCE TRANSLATION
                                            OF CHANNEL PROGRAM FOR THIS
                                            DEVICE
              .... .1..      VDEVTENB       X'04' VDEVTENB TAPE Device has
                                            not been enabled. Device End has
                                            not been presented.
              .... ..1.      VDEVSHRD       X'02' VDEVSHRD Multiuser device
                                            bit
              .... ...1      VDEVSHND       X'01' VDEVSHND Multiuser/Detach
                                            ALL fails for vdev
    0020   32 Bitstring   28 VDEVPMCW       PATH MANAGEMENT CONTROL WORD
    003C   60 Signed       4 VDEVAIOR       Host logical address of active
                                            IORBK
    0040   64 Signed       4 VDEVNIOR       SSCH pending (not yet started)
                                            IORBK Host logical address of an
                                            IORBK.
    0044   68 Address      4 VDEVSIOR       IORBK holding sense data for
                                            device. Host logical address of
                                            an IORBK.
    0048   72 Signed       4 VDEVIORQ       RDEV-to-VDEV lock swapping pivot
                                            Host logical address of an IORBK.
    004C   76 Signed       4 VDEVPIOR       HL @ of Pending interrupt IORBK
    0050   80 Signed       4 VDEVENDQ       COMPLETION TASK QUEUE ANCHOR
    0054   84 Address      4 VDEVDEOT       DELAYED ENDOP TRQBK ANCHOR
    0058   88 Signed       4 VDEVRDEV       Host logical address of RDEV of
                                            actual device.
    005C   92 Address      4 VDEVAEVT       POINTER TO LIST OF ASYNCHRONOUS
                                            EVENTS IN THIS VDEV.
    0060   96 Signed       4 *              Reserved for future IBM use.
    0064  100 Address      4 VDEVCEOT       POINTER TO 20 SECOND TIMER
    0068  104 Address      4 VDEVLMSG       CFLF In-line Message Block
                                            Pointer
    006C  108 Signed       4 VDEVIOCT       Count of virtual I/O requests
                                            issued to the virtual device.
                                            (See VDEVIOCA). Not applicable to
                                            consoles, virtual spool or I/O
                                            Assist devices.
    0070  112 Dbl-Word     8 VDEVTIME (0)   TOD CLOCK AT DEVICE CREATION
    0070  112 Signed       4 VDEVTIMH       HI ORDER TOD CLOCK ROUGHLY IN
                                            SECONDS
    0074  116 Signed       4 VDEVTIML       LO ORDER TOD CLOCK
    0078  120 Signed       4 VDEVSPEC (10)  DEVICE-DEPENDENT SPECIFICATIONS
    00A0  160 Address      4 VDEVIOMI       Address of Virtual I/O Management
                                            Info
    00A4  164 Address      4 VDEVUIOR       Pending unsolicited IORBK came in
                                            after unit check
    00A8  168 Signed       4 VDEVIOCA       Count of actual I/O operations
                                            initiated by CP for this virtual
                                            device. Not applicable to
                                            consoles, virtual spool or I/O
                                            Assist devices. Notes : This
                                            value may be lower than the
                                            number of virtual I/O requests if
                                            data can be obtained thru MDC, or
                                            it may be higher, if a virtual
                                            I/O request is broken up by CP
                                            into more than one actual I/O
                                            request (e.g., a diagnose x'A4'
                                            request for blocks on multiple
                                            cylinders.
    00AC  172 Signed       4 VDEVATIM       Time of device creation or last
                                            ACNT, whichever is later
    00B0  176 Bitstring    1 VDEVIOP1       I/O PASS THROUGH FLAGS
              1... ....      VDEVIOPQ       X'80' VDEVIOPQ User set QIOAssist
                                            off for the device
              .1.. ....      VDEVIOPA       X'40' VDEVIOPA DEV IS OPERATING
                                            UNDER PASS THROUGH
              ..1. ....      VDEVIOPI       X'20' VDEVIOPI DEV BEING PUT
                                            UNDER I/O PASS THROUGH
              ...1 ....      VDEVIOPO       X'10' VDEVIOPO TAKE DEVICE OUT OF
                                            PASS THROUGH AT NEXT OPPORTUNITY
              .... 1...      VDEVIOPR       X'08' VDEVIOPR DEV BEING REMOVED
                                            FROM PASS THROUGH
              .... .1..      VDEVIOPS       X'04' VDEVIOPS User set I/O
                                            Assist off for the device
              .... ..1.      VDEVIOPX       X'02' VDEVIOPX DEVICE IS ELIGIBLE
                                            FOR XA I/O PASS THROUGH
              .... ...1      VDEVIOP3       X'01' VDEVIOP3 DEVICE IS ELIGIBLE
                                            FOR 370 I/O PASS THROUGH
    00B1  177 Bitstring    1 VDEVMODL       VIRTUAL DEVICE MODEL NUMBER
    00B2  178 Bitstring    1 VDEVCPIE       CHANNEL PATH IN ERROR MASK
    00B3  179 Bitstring    1 VDEVCRDR       Count of I/O redrives to
                                            simulation
    00B4  180 Signed       4 VDEVIUBK       I/O Assist Utilization Block
                                            Address
    00B8  184 Bitstring    1 VDEVLCNT       CURRENT LINE COUNT
    00B9  185 Bitstring    1 VDEVLTOD (3)   BYTES 2-4 OF TOD CLOCK WHEN LCNT
                                            RESET
    00BC  188 Address      4 VDEVBKIA       Address of the BKIBK This field
                                            is serialized by: If = 0,
                                            compare-and-swap if ^=0, BKILOCK
                                            held exclusive and
                                            single-access-word-current-store.
    00C0  192 Address      4 VDEVIPTS       Used by HCPIPT to contain a
                                            pointer to the SCHIB before a
                                            CSCH is done.
    00C4  196 Bitstring    1 *              Reserved for future IBM use
    00C5  197 Bitstring    1 VDEVPMSK       Mask of path on which the
                                            Quiesce/Resume message was
                                            received
    00C6  198 Bitstring    1 VDEVVNET       Virtual Network Simulation flags
              1... ....      VDEVNSIM       X'80' VDEVNSIM Virtual Network
                                            Simulation is ACTIVE (this means
                                            VDEVNIP is active)
              .1.. ....      VDEVVSW        X'40' VDEVVSW Virtual SWITCH
                                            (VSWITCH) device
    00C7  199 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
                 RESERVED FIELDS FOR INSTALLATION USE
                 THIS AREA IS PERMANENTLY AVAILABLE, BUT MAY
                 BE MOVED TO ANOTHER OFFSET IN THE BLOCK AT
                 A LATER RELEASE OF THE SYSTEM.
    00C8  200 Signed       4 VDEVUSR1       RESERVED FOR INSTALLATION USE
    00CC  204 Signed       4 VDEVUSR2       RESERVED FOR INSTALLATION USE
    00D0  208 Signed       4 VDEVUSR3       RESERVED FOR INSTALLATION USE
    00D4  212 Signed       4 VDEVUSR4       RESERVED FOR INSTALLATION USE
                 End of Installation reserved fields
    00D8  216 Signed       4 *              Reserved for future IBM use
    00DC  220 Signed       4 VDEVRTMR       Pointer to RESET TRQBK. This
                                            field is serialized by VDEV lock
                                            when it is set and the dispatch
                                            lock when the field is reset.
    00E0  224 Signed       4 VDEVTRKF       First relative track for device
    00E4  228 Signed       4 VDEVTRKL       Last relative track for device
    00E8  232 Signed       4 VDEVARSL       Pointer to next Diag 254 pseudo
                                            vdev
    00EC  236 Signed       4 VDEVARSI       Pointer to Diag 254 information
                                            block
    00F0  240 Signed       4 VDEVARPV       Pointer to Diag 254 parent vdev
    00F4  244 Bitstring    1 VDEVMDFG       Message Device Flag
              1... ....      VDEVMDEL       X'80' VDEVMDEL Message Device
                                            Deleted
    00F5  245 Bitstring    1 * (3)          Reserved for future IBM use
    00F8  248 Address      4 VDEVQDIO       HL address of the QDIO block.
    00FC  252 Address      4 VDEVAIF        HL address of Adapter
                                            Interruption Facility Block.
                                            (AIFBK).
    0100  256 Address      4 VDEVSHTP       MULTIuser tape device forward
                                            pointer
    0104  260 Address      4 VDEVIODD       CCW TRACE IODATA buffer
    0108  264 Dbl-Word     8 VDEVMBLK (0)   64-bit measurement block address
    0108  264 Signed       4 VDEVMBAH       High order MBA word
    010C  268 Signed       4 VDEVMBAL       Low order MBA word
              VDEVMBAL       VDEVMBAO       VDEVMBAL VDEVMBAO 390 measurement
                                            block address
          Parallel Access Volume Support
    0110  272 Signed       2 VDEVHPPL       HyperPAV Pool Number
    0112  274 Bitstring    1 VDEVPVFG       PAV Flags
              1... ....      VDEVPVBA       X'80' VDEVPVBA PAV Base Device
              .1.. ....      VDEVPVAL       X'40' VDEVPVAL PAV Alias Device
              ..1. ....      VDEVHPBA       X'20' VDEVHPBA HyperPAV Base
                                            Device
              ...1 ....      VDEVHPAL       X'10' VDEVHPAL HyperPAV Alias
                                            Device
              .... 1...      VDEVUVAL       X'08' VDEVUVAL PAV Unit Address
                                            Valid
              000000F0       VDEVPVHP       (VDEVPVBA+VDEVPVAL+VDEVHPBA+VDEVH
                                            PAL) PAV/Hyperpav summary bits
    0113  275 Bitstring    1 VDEVUNIT       Dynamic PAV Unit Address
    0114  276 Address      4 VDEVPAVB       Addr of PAV VDEV Base
    0118  280 Address      4 VDEVPAVP       Addr of PAV VDEV Alias bak ptr
    011C  284 Address      4 VDEVPAVA       Addr of PAV VDEV Alias fwd ptr
    0120  288 Address      4 VDEVPREF       Addr of PAV Referenced Base or
                                            Alias
          Guest Characteristics
             Store (ST) and Load (L) this field to/from a register
             in whole to prevent other tasks from getting partial
             updates.  This is the only serialization provided for
             this field.
    0124  292 Signed       4 VDEVGCHR       Guest Characteristics
                 Start VDEV overlay area
              00000128       VDEVBYSZ       *-VDEV VDEV size in bytes
              00000025       VDEVSIZE       ((*-VDEV)+7)/8 VDEV SIZE IN
                                            DOUBLE-WORDS
    0078  120 Signed       4 VDEVPOSN_CCCH (0)
                                            VIRTUAL DASD ARM POSITION
    0078  120 Signed       4 VDEVPOSN (0)   VIRTUAL DASD ARM POSITION
    0078  120 Signed       2 VDEVCYLN       VIRTUAL DASD CYLINDER NUMBER
              .111 1...      VDEVCYL0       00001 VDEVCYLN,1 1ST BYTE OF
                                            CYLINDER INFORMATION
              .111 1..1      VDEVCYL1       00001 VDEVCYLN+1,1 2ND BYTE OF
                                            CYLINDER INFORMATION
    007A  122 Signed       2 VDEVHEAD       VIRTUAL DASD HEAD NUMBER
              .111 1.1.      VDEVHED0       00001 VDEVHEAD,1 1ST BYTE OF HEAD
                                            INFORMATION
              .111 1.11      VDEVHED1       00001 VDEVHEAD+1,1 2ND BYTE OF
                                            HEAD INFORMATION
    007C  124 Signed       4 VDEVSEXT (0)   Minidisk Start of EXTent. May be
                                            in cylinders (CKD/ECKD) or
                                            blocks(FBA)
    007C  124 Signed       2 *              Filler for beginning cylinder
    007E  126 Signed       2 VDEVBCYL       Minidisk beginning cylinder
    0080  128 Signed       4 VDEVEEXT (0)   Minidisk End of EXTent. May be in
                                            cylinders (CKD/ECKD) or
                                            blocks(FBA)
    0080  128 Signed       2 *              Filler for last cylinder
    0082  130 Signed       2 VDEVLCYL       Minidisk last cylinder
    0084  132 Signed       4 VDEVLINK       Next VDEV on this MDISK (cf.
                                            VDEVLINP)
    0088  136 Signed       4 VDEVBIOA       BLOCK I/O CONNECT BLOCK
    008C  140 Signed       4 VDEVMDSK       MINI-DISK BLOCK FOR
                                            RESERVE/RELEASE
    0090  144 Address      4 VDEVHPLK       Pointer to next hyperpav alias
                                            VDEV in the list anchored in
                                            RDEVHPLK
    0094  148 Bitstring    1 VDEVMNGT       LEVEL OF CONTROL FOR CACHED DASD
              1... ....      VDEVCA         X'80' VDEVCA CACHING AVAILABLE TO
                                            A MINIDISK
              .1.. ....      VDEVCNA        X'40' VDEVCNA CACHING NOT
                                            AVAILABLE TO A MINIDISK
              ..1. ....      VDEVSCTL       X'20' VDEVSCTL SYSTEM CONTROL FOR
                                            CACHED DASD
              ...1 ....      VDEVDCTL       X'10' VDEVDCTL DEVICE CONTROL FOR
                                            CACHED DASD
              .... 1...      VDEVNCTL       X'08' VDEVNCTL NO CONTROL FOR
                                            CACHED DASD
    0095  149 Bitstring    1 VDEVSFLG       DASD SPECIFIC FLAG
              ...1 ....      VDEVRFID       X'10' VDEVRFID READ CACHE
                                            FASTWRITE ID CCW ISSUED
              .... 1...      VDEVSCPI       X'08' VDEVSCPI REFLECT A
                                            STATE-CHANGE INTERRUPT WHEN A
                                            STATE-CHANGE-PENDING CONDITION
                                            ENDS
    0096  150 Bitstring    2 *              RESERVED FOR FUTURE IBM USE
    0098  152 Signed       2 VDEVMPCT       COUNT OF EXTENTS DEFINED FOR THIS
                                            MINIDISK.
    009A  154 Signed       2 *              RESERVED FOR IBM USE
    009C  156 Signed       4 VDEVLINP       Prev VDEV on this MDISK
                                            (cf.VDEVLINK) (Previous of head
                                            is tail but Next of tail is
                                            zero.)
    0078  120 Bitstring   36 *              RESERVED FOR FUTURE IBM USE
    009C  156 Address      4 VDEVDYPT       Pointer to Tape Pathing Control
                                            Block
    0078  120 Character    8 VDEVCUSR       RESTRICTED USERID FOR COUPLING
    0080  128 Address      4 VDEVCTCA       ADDRESS OF CACBK
    0084  132 Bitstring    4 VDEVCTCD       CTCA designation 3088 = 3088
                                            emulation SCTC = ESCON SCTC
                                            emulation BCTC = ESCON BCTC
                                            emulation CNC = ESCON CNC
                                            emulation FCTC = FICON emulation
    0088  136 Bitstring   24 *              Reserved for IBM use
          Overlay for a fully-simulated Virtual Network device.
          This definition is active whenever VDEVNSIM is ON.
              00000078       VDEVNIP        * Network Interface Properties
    0078  120 Character    4 VDEVNIFT       Interface Type (e.g. c'IQDC')
    007C  124 Signed       4 VDEVNIDX       Index of this NID in the adapter
    0080  128 Address      4 VDEVNIC        Host logical address of adapter
                                            NICBK
    0084  132 Address      4 VDEVNID        Host logical address of device
                                            NIDBK
    0088  136 Address      4 VDEVSIGA       SIGA Simulation Routine Linkage:
                                            HCPCALL R15 Input/Output: Like
                                            HCPIQQWR TMODEAR or TMODESTD
    008C  140 Bitstring    4 VDEVQMSK       QDIO Queue Selection Mask
    0090  144 Bitstring    1 VDEVOTSK       QDIO Output Queue Processing Task
    0091  145 Bitstring    1 VDEVITSK       QDIO Input Queue Processing Task
    0092  146 Bitstring    1 VDEVSWFL       VSWITCH Flags
              1... ....      VDEVSWDD       X'80' VDEVSWDD VSWITCH DATA
                                            device
              .... ...1      VDEVD2A8       X'01' VDEVD2A8 QDIO Diagnose 2A8
                                            Device Connection
    0093  147 Bitstring    1 VDEVSBSY       SIGA Busy Counter
    0094  148 Signed       4 VDEVCHKQ       Checking queues (stacked call)
    0098  152 Bitstring    8 *              Reserved for IBM Use
    0078  120 Signed       4 *              RESERVED FOR FUTURE IBM USE
    007C  124 Address      4 VDEVVSP        ADDRESS OF THE VIRTUAL SPOOL
                                            BLOCK
    0080  128 Address      4 VDEVVPX        ADDRESS OF PRT EXTENSION BLOCK
    0084  132 Address      4 VDEVVDS        DEVICE SIMULATION POINTER
    0088  136 Bitstring   24 *              RESERVED FOR FUTURE IBM USE
    0078  120 Address      4 VDEVMNPT       Pointer to Next Message Device
    007C  124 Address      4 VDEVLCF        Address of Lock Facility Data
                                            Block
    0080  128 Address      4 VDEVLFIO       Address Of Lock Facility IORBK
    0084  132 Bitstring    1 VDEVMCHP (8)   Message Facility CHPIDs
    008C  140 Bitstring   20 *              Reserved for Future IBM Use
    0020   32 Signed       4 VDEVPMW0 (0)   WORD 0 OF PMCW
    0020   32 Signed       4 VDEVINTP       INTERRUPT PARAMETER
    0024   36 Signed       4 VDEVPMW1 (0)   WORD 1 OF PMCW
    0024   36 Bitstring    1 VDEVIRCF       SUBCHANNEL INTERUPT REQUEST CODE
              ..11 1...      CSWIRC         X'38' CSWIRC INTERRUPTION
                                            SUBCLASS EXTRACT MASK
              1... ....      CSWQDIO        X'80' CSWQDIO QDIO Facility (Q)
                                            Available
              .... .1..      CSWIOINC       X'04' CSWIOINC I/O Initiation
                                            Control bit
              .... ..1.      CSWHDVA        X'02' CSWHDVA HALT DEVICE (HDV)
                                            Assist Control bit
              .... ...1      CSWABC         X'01' CSWABC ALTERNATE BLOCK
                                            CONTROL BIT
              1... ....      CSWPATH        X'80' CSWPATH MODEL DEPENDENT
                                            PATH FOR MSG SUBCHANL
              ..11 111.      CSWMSV         X'3E' CSWMSV MESSAGE SUBCHANNEL
                                            VALID BITS
              .1.. ....      CSWMINS        X'40' CSWMINS MESSAGE DEVICE MAY
                                            BE INSTALLED
    0025   37 Bitstring    1 VDEVCTL        SUBCHANNEL STATUS CONTROL
    0026   38 Bitstring    2 VDEVDEV (0)    INTERNAL DEVICE NUMBER
    0026   38 Bitstring    1 VDEVDEVC       CHANNEL NUMBER
    0027   39 Bitstring    1 VDEVDEVU       DEVICE/CONTROL UNIT NUMBER
    0028   40 Signed       4 VDEVPMW2 (0)   WORD 2 OF PMCW
    0028   40 Bitstring    1 VDEVLPM        SUBCHANNEL LOGICAL PATH MASK
    0029   41 Bitstring    1 VDEVPNOM       SUBCHANNEL PATH NOT OPERATIONAL
                                            MASK
    002A   42 Bitstring    1 VDEVLPUM       SUBCHANNEL LAST PATH USED MASK
    002B   43 Bitstring    1 VDEVPIM        SUBCHANNEL PATH INSTALLED MASK
    002C   44 Signed       4 VDEVPMW3 (0)   WORD 3 OF PMCW
    002C   44 Signed       2 VDEVMBI        MEASUREMENT BLOCK INDEX
    002E   46 Bitstring    1 VDEVPOM        SUBCHANNEL OPERATIONAL MASK
    002F   47 Bitstring    1 VDEVPAM        SUBCHANNEL PATH AVAILABLE MASK
    0030   48 Bitstring    1 VDEVCPID (8)   CHANNEL PATH IDENTIFIERS 0 - 7
    0038   56 Signed       4 VDEVPMW6 (0)   WORD 6 OF PMCW
    0038   56 Bitstring    1 VDEVZONE       ZONE
    0039   57 Bitstring    1 VDEVVISC       GUEST ISC
              .1.. ....      VDEVMSGS       X'40' VDEVMSGS Type of Subchannel
                                            is Message
              ..1. ....      VDEVDYN        X'20' VDEVDYN Type of Subchaneel
                                            is DYN I/O (ST=1)
    003A   58 Bitstring    1 *              RESERVED
    003B   59 Bitstring    1 VDEVECFG       EXTENDED CONTROL FLAGS
    0010   16 Bitstring    1 VDEVSUBL       LEFT DIGIT OF SUBCHANNEL NUMBER
    0011   17 Bitstring    1 VDEVSUBR       RIGHT DIGIT OF SUBCHANNEL NUMBER

#### VDEV Storage Layout

    *** VDEV - VIRTUAL DEVICE CONTROL BLOCK
    *
    *     +---------------------------+---------------------------+
    *   0 |         VDEVFPNT          |         VDEVBPNT          |
    *     +---------------------------+---------------------------+
    *   8 |         VDEVLOWN          |         VDEVTSKQ          |
    *     +-------------+------+------+---------------------------+
    *  10 |  VDEVSUB    |:VCLAS|:VTYPE|         VDEVUSER          |
    *     +------+------+------+------+------+------+------+------+
    *  18 |:VSTAT|:VWAIT|:VAFLG|:VBFLG|:VDFLG|:VCFLG|:VFFLG|:VPFLG|
    *     +------+------+------+------+------+------+------+------+
    *  20 |                                                       |
    *     =                       VDEVPMCW                        =
    *     |                           +---------------------------+
    *  38 |                           |         VDEVAIOR          |
    *     +---------------------------+---------------------------+
    *  40 |         VDEVNIOR          |         VDEVSIOR          |
    *     +---------------------------+---------------------------+
    *  48 |         VDEVIORQ          |         VDEVPIOR          |
    *     +---------------------------+---------------------------+
    *  50 |         VDEVENDQ          |         VDEVDEOT          |
    *     +---------------------------+---------------------------+
    *  58 |         VDEVRDEV          |         VDEVAEVT          |
    *     +---------------------------+---------------------------+
    *  60 |///////////////////////////|         VDEVCEOT          |
    *     +---------------------------+---------------------------+
    *  68 |         VDEVLMSG          |         VDEVIOCT          |
    *     +---------------------------+---------------------------+
    *  70 |         VDEVTIMH          |         VDEVTIML          |
    *     +---------------------------+---------------------------+
    *  78 |                                                       |
    *     =                       VDEVSPEC                        =
    *     |                                                       |
    *     +---------------------------+---------------------------+
    *  A0 |         VDEVIOMI          |         VDEVUIOR          |
    *     +---------------------------+---------------------------+
    *  A8 |         VDEVIOCA          |         VDEVATIM          |
    *     +------+------+------+------+---------------------------+
    *  B0 |:VIOP1|:VMODL|:VCPIE|:VCRDR|         VDEVIUBK          |
    *     +------+------+------+------+---------------------------+
    *  B8 |:VLCNT|     VDEVLTOD       |         VDEVBKIA          |
    *     +------+--------------------+------+------+------+------+
    *  C0 |         VDEVIPTS          |//////|:VPMSK|:VVNET|//////|
    *     +---------------------------+------+------+------+------+
    *  C8 |         VDEVUSR1          |         VDEVUSR2          |
    *     +---------------------------+---------------------------+
    *  D0 |         VDEVUSR3          |         VDEVUSR4          |
    *     +---------------------------+---------------------------+
    *  D8 |///////////////////////////|         VDEVRTMR          |
    *     +---------------------------+---------------------------+
    *  E0 |         VDEVTRKF          |         VDEVTRKL          |
    *     +---------------------------+---------------------------+
    *  E8 |         VDEVARSL          |         VDEVARSI          |
    *     +---------------------------+------+--------------------+
    *  F0 |         VDEVARPV          |:VMDFG|////////////////////|
    *     +---------------------------+------+--------------------+
    *  F8 |         VDEVQDIO          |         VDEVAIF           |
    *     +---------------------------+---------------------------+
    * 100 |         VDEVSHTP          |         VDEVIODD          |
    *     +---------------------------+---------------------------+
    * 108 |         VDEVMBAH          |         VDEVMBAL          |
    *     +-------------+------+------+---------------------------+
    * 110 |  VDEVHPPL   |:VPVFG|:VUNIT|         VDEVPAVB          |
    *     +-------------+------+------+---------------------------+
    * 118 |         VDEVPAVP          |         VDEVPAVA          |
    *     +---------------------------+---------------------------+
    * 120 |         VDEVPREF          |         VDEVGCHR          |
    *     +---------------------------+---------------------------+
    * 128
    *
    *** VDEV - VIRTUAL DEVICE CONTROL BLOCK

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +-------------+-------------+-------------+-------------+
    *  78 |  VDEVCYLN   |  VDEVHEAD   |/////////////|  VDEVBCYL   |
    *     +-------------+-------------+-------------+-------------+
    *  80 |/////////////|  VDEVLCYL   |         VDEVLINK          |
    *     +-------------+-------------+---------------------------+
    *  88 |         VDEVBIOA          |         VDEVMDSK          |
    *     +---------------------------+------+------+-------------+
    *  90 |         VDEVHPLK          |:VMNGT|:VSFLG|/////////////|
    *     +-------------+-------------+------+------+-------------+
    *  98 |  VDEVMPCT   |/////////////|         VDEVLINP          |
    *     +-------------+-------------+---------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +-------------------------------------------------------+
    *  78 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////+---------------------------+
    *  98 |///////////////////////////|         VDEVDYPT          |
    *     +---------------------------+---------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +-------------------------------------------------------+
    *  78 |                       VDEVCUSR                        |
    *     +---------------------------+---------------------------+
    *  80 |         VDEVCTCA          |         VDEVCTCD          |
    *     +---------------------------+---------------------------+
    *  88 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +---------------------------+---------------------------+
    *  78 |         VDEVNIFT          |         VDEVNIDX          |
    *     +---------------------------+---------------------------+
    *  80 |         VDEVNIC           |         VDEVNID           |
    *     +---------------------------+---------------------------+
    *  88 |         VDEVSIGA          |         VDEVQMSK          |
    *     +------+------+------+------+---------------------------+
    *  90 |:VOTSK|:VITSK|:VSWFL|:VSBSY|         VDEVCHKQ          |
    *     +------+------+------+------+---------------------------+
    *  98 |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +---------------------------+---------------------------+
    *  78 |///////////////////////////|         VDEVVSP           |
    *     +---------------------------+---------------------------+
    *  80 |         VDEVVPX           |         VDEVVDS           |
    *     +---------------------------+---------------------------+
    *  88 |///////////////////////////////////////////////////////|
    *     =///////////////////////////////////////////////////////=
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVSPEC in VDEV
    *
    *     +---------------------------+---------------------------+
    *  78 |         VDEVMNPT          |         VDEVLCF           |
    *     +---------------------------+---------------------------+
    *  80 |         VDEVLFIO          |        VDEVMCHP-          |
    *     +---------------------------+---------------------------+
    *  88 |          -(084)           |///////////////////////////|
    *     +---------------------------+///////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  A0
    *
    *** Overlay for VDEVSPEC in VDEV

    *** Overlay for VDEVPMCW in VDEV
    *
    *     +---------------------------+------+------+------+------+
    *  20 |         VDEVINTP          |:VIRCF|:VCTL |:VDEVC|:VDEVU|
    *     +------+------+------+------+------+------+------+------+
    *  28 |:VLPM |:VPNOM|:VLPUM|:VPIM |  VDEVMBI    |:VPOM |:VPAM |
    *     +------+------+------+------+-------------+------+------+
    *  30 |                       VDEVCPID                        |
    *     +------+------+------+------+---------------------------+
    *  38 |:VZONE|:VVISC|//////|:VECFG| 3C
    *     +------+------+------+------+
    *
    *** Overlay for VDEVPMCW in VDEV

    *** Overlay for VDEVSUB in VDEV
    *
    *     +------+------+
    *  10 |:VSUBL|:VSUBR| 12
    *     +------+------+
    *
    *** Overlay for VDEVSUB in VDEV

#### VDEV Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    CLASAIF        0012 FF
    CLASDASD       0012 04
    CLASGRAF       0012 40
    CLASGRFR       0012 41
    CLASPOOL       0012 20
    CLASSPEC       0012 02
    CLASSVCM       0012 10
    CLASSWCH       0012 01
    CLASTAPE       0012 08
    CLASTERM       0012 80
    CSWABC         0024 01
    CSWHDVA        0024 02
    CSWIOINC       0024 04
    CSWIRC         0024 38
    CSWMINS        0024 40
    CSWMSV         0024 3E
    CSWPATH        0024 80
    CSWQDIO        0024 80
    TYPAFP1        0013 27
    TYPALIAS       0013 03
    TYPBSC         0013 88
    TYPCLUST       0013 30
    TYPCONS        0013 40
    TYPCTCA        0013 80
    TYPDYNIO       0013 02
    TYPELAN        0013 28
    TYPFBA         0013 28
    TYPFCP         0013 10
    TYPHDLC        0013 24
    TYPIBM1        0013 10
    TYPIC          0013 02
    TYPILAN        0013 28
    TYPMSGF        0013 01
    TYPOSA         0013 20
    TYPPRT         0013 20
    TYPPUN         0013 40
    TYPRDR         0013 80
    TYPSDLC        0013 08
    TYPSYS         0013 10
    TYPTELE2       0013 20
    TYPTTY         0013 20
    TYPUNDEF       0013 1C
    TYPUNSUP       0013 01
    TYPVAFP        0013 2A
    TYP1050        0013 14
    TYP1052        0013 40
    TYP1403        0013 21
    TYP2032        0013 20
    TYP2250        0013 04
    TYP2305        0013 08
    TYP2501        0013 81
    TYP2540P       0013 42
    TYP2540R       0013 82
    TYP2700        0013 80
    TYP2741        0013 18
    TYP3088        0013 80
    TYP3178        0013 40
    TYP3179        0013 40
    TYP3180        0013 40
    TYP3190        0013 40
    TYP32XX        0013 22
    TYP3203        0013 26
    TYP3211        0013 22
    TYP3215        0013 40
    TYP3250        0013 04
    TYP3262        0013 23
    TYP3270        0013 40
    TYP3271        0013 20
    TYP3275        0013 10
    TYP3277        0013 80
    TYP3278        0013 40
    TYP3279        0013 40
    TYP3284        0013 08
    TYP3286        0013 08
    TYP3287        0013 09
    TYP3287L       0013 08
    TYP3288        0013 08
    TYP3289        0013 09
    TYP3289L       0013 08
    TYP3290        0013 40
    TYP3330        0013 40
    TYP3340        0013 20
    TYP3350        0013 10
    TYP3350C       0013 11
    TYP3350D       0013 12
    TYP3370        0013 02
    TYP3375        0013 80
    TYP3380        0013 04
    TYP3390        0013 82
    TYP3420        0013 10
    TYP3422        0013 80
    TYP3424        0013 42
    TYP3430        0013 20
    TYP3480        0013 40
    TYP3490        0013 81
    TYP3505        0013 84
    TYP3525        0013 44
    TYP3590        0013 83
    TYP3704        0013 40
    TYP3705        0013 40
    TYP3767        0013 18
    TYP3800        0013 28
    TYP3820        0013 25
    TYP3851        0013 02
    TYP3890        0013 08
    TYP4245        0013 24
    TYP4248        0013 29
    TYP5080        0013 06
    TYP9032        0013 80
    TYP9033        0013 40
    TYP9332        0013 21
    TYP9335        0013 22
    TYP9336        0013 24
    TYP9345        0013 81
    TYP9348        0013 44
    VDEVACTV       0018 F0
    VDEVAEVT       005C
    VDEVAFLG       001A
    VDEVAIF        00FC
    VDEVAIOR       003C
    VDEVARPV       00F0
    VDEVARSI       00EC
    VDEVARSL       00E8
    VDEVATIM       00AC
    VDEVATTN       001D 08
    VDEVBCC0       001B 80
    VDEVBCYL       007E
    VDEVBFLG       001B
    VDEVBIOA       0088
    VDEVBKIA       00BC
    VDEVBPCI       001B 40
    VDEVBPNT       0004
    VDEVBRGS       001D 04
    VDEVBSUI       001B 20
    VDEVBUSY       0018 80
    VDEVBYSZ       0124 00000128
    VDEVCA         0094 80
    VDEVCATT       0018 01
    VDEVCEOT       0064
    VDEVCFLG       001D
    VDEVCHKQ       0094
    VDEVCLAS       0012
    VDEVCLRF       0018 20
    VDEVCMS        001B 04
    VDEVCNA        0094 40
    VDEVCODE       0012
    VDEVCPCL       001F 80
    VDEVCPID       0030
    VDEVCPIE       00B2
    VDEVCRDR       00B3
    VDEVCTCA       0080
    VDEVCTCD       0084
    VDEVCTL        0025
    VDEVCUSR       0078
    VDEVCYLN       0078
    VDEVCYL0       0078 78
    VDEVCYL1       0078 79
    VDEVDCTL       0094 10
    VDEVDED        001A 08
    VDEVDEOT       0054
    VDEVDEV        0026
    VDEVDEVC       0026
    VDEVDEVU       0027
    VDEVDFLG       001C
    VDEVDIAL       001C 20
    VDEVDING       001D 10
    VDEVDPRE       001F 10
    VDEVDTCH       001A 01
    VDEVDVFP       001E 20
    VDEVDYN        0039 20
    VDEVDYPT       009C
    VDEVD2A8       0092 01
    VDEVECFG       003B
    VDEVEEXT       0080
    VDEVENAB       001C 40
    VDEVENDQ       0050
    VDEVFBA        001E 08
    VDEVFFLG       001E
    VDEVFPNT       0000
    VDEVFPO        001A 02
    VDEVFULL       001A 10
    VDEVGCHR       0124
    VDEVGCWE       001C 01
    VDEVGSUS       001D 20
    VDEVHEAD       007A
    VDEVHED0       007A 7A
    VDEVHED1       007A 7B
    VDEVHLTF       0018 10
    VDEVHPAL       0112 10
    VDEVHPBA       0112 20
    VDEVHPLK       0090
    VDEVHPPL       0110
    VDEVIMRS       0019 80
    VDEVINTP       0020
    VDEVINTV       001A 80
    VDEVINT3       001D 80
    VDEVIOCA       00A8
    VDEVIOCT       006C
    VDEVIODD       0104
    VDEVIOMI       00A0
    VDEVIOPA       00B0 40
    VDEVIOPI       00B0 20
    VDEVIOPO       00B0 10
    VDEVIOPQ       00B0 80
    VDEVIOPR       00B0 08
    VDEVIOPS       00B0 04
    VDEVIOPX       00B0 02
    VDEVIOP1       00B0
    VDEVIOP3       00B0 01
    VDEVIORQ       0048
    VDEVIPTS       00C0
    VDEVIRCF       0024
    VDEVITSK       0091
    VDEVIUBK       00B4
    VDEVLCF        007C
    VDEVLCNT       00B8
    VDEVLCYL       0082
    VDEVLFIO       0080
    VDEVLINK       0084
    VDEVLINP       009C
    VDEVLMSG       0068
    VDEVLNKE       001E 40
    VDEVLNKS       001E 80
    VDEVLOCK       0008
    VDEVLOWN       0008
    VDEVLPM        0028
    VDEVLPUM       002A
    VDEVLTOD       00B9
    VDEVMBAH       0108
    VDEVMBAL       010C
    VDEVMBAO       010C VDEVMBAL
    VDEVMBI        002C
    VDEVMBLK       0108
    VDEVMCHP       0084
    VDEVMDEL       00F4 80
    VDEVMDFG       00F4
    VDEVMDSK       008C
    VDEVMNGT       0094
    VDEVMNPT       0078
    VDEVMODL       00B1
    VDEVMPCT       0098
    VDEVMPLX       001A 04
    VDEVMSGS       0039 40
    VDEVNCTL       0094 08
    VDEVNIC        0080
    VDEVNID        0084
    VDEVNIDX       007C
    VDEVNIFT       0078
    VDEVNIOR       0040
    VDEVNIP        0088 00000078
    VDEVNOTO       001C 08
    VDEVNRSM       001F 20
    VDEVNSEG       001C 02
    VDEVNSIM       00C6 80
    VDEVOTSK       0090
    VDEVPAM        002F
    VDEVPAVA       011C
    VDEVPAVB       0114
    VDEVPAVP       0118
    VDEVPFLG       001F
    VDEVPIM        002B
    VDEVPIOR       004C
    VDEVPMCW       0020
    VDEVPMSK       00C5
    VDEVPMW0       0020
    VDEVPMW1       0024
    VDEVPMW2       0028
    VDEVPMW3       002C
    VDEVPMW6       0038
    VDEVPNOM       0029
    VDEVPOM        002E
    VDEVPOSN       0078
    VDEVPOSN_CCCH  0078
    VDEVPPA1       001D 40
    VDEVPRCE       0018 40
    VDEVPREF       0120
    VDEVPURG       001F 40
    VDEVPVAL       0112 40
    VDEVPVBA       0112 80
    VDEVPVFG       0112
    VDEVPVHP       0112 000000F0
    VDEVQACT       001B 08
    VDEVQDIO       00F8
    VDEVQDSK       001E 10
    VDEVQMSK       008C
    VDEVQUED       0018 02
    VDEVRDEV       0058
    VDEVRFID       0095 10
    VDEVRMLF       001E 04
    VDEVRO         001C 80
    VDEVRPND       0018 04
    VDEVRSRL       001C 04
    VDEVRTMR       00DC
    VDEVSBSY       0093
    VDEVSCPI       0095 08
    VDEVSCTL       0094 20
    VDEVSDIA       001C 10
    VDEVSEXT       007C
    VDEVSFLG       0095
    VDEVSHND       001F 01
    VDEVSHRD       001F 02
    VDEVSHTP       0100
    VDEVSIGA       0088
    VDEVSIOR       0044
    VDEVSIZE       0124 00000025
    VDEVSPEC       0078
    VDEVSTAT       0018
    VDEVSUB        0010
    VDEVSUBL       0010
    VDEVSUBR       0011
    VDEVSULF       001E 02
    VDEVSUSP       0018 08
    VDEVSWDD       0092 80
    VDEVSWFL       0092
    VDEVTDSK       001A 40
    VDEVTENB       001F 04
    VDEVTIME       0070
    VDEVTIMH       0070
    VDEVTIML       0074
    VDEVTRCW       001F 08
    VDEVTRKF       00E0
    VDEVTRKL       00E4
    VDEVTSKQ       000C
    VDEVTYPE       0013
    VDEVUIOR       00A4
    VDEVUNIT       0113
    VDEVUSER       0014
    VDEVUSR1       00C8
    VDEVUSR2       00CC
    VDEVUSR3       00D0
    VDEVUSR4       00D4
    VDEVUVAL       0112 08
    VDEVVDS        0084
    VDEVVISC       0039
    VDEVVMIO       001B 02
    VDEVVNET       00C6
    VDEVVPX        0080
    VDEVVSIM       001A 20
    VDEVVSP        007C
    VDEVVSW        00C6 40
    VDEVWAIT       0019
    VDEVWINT       0019 40
    VDEVZONE       0038
    VDEV3DSK       001E 01

This information is based on z/VM V6R1.0. Last updated on 18 Feb 2010 at 09:21:06 EDT.
Copyright IBM Corporation, 1990, 2008