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

#### XDRBK

Prolog

Control Block Contents
XDRBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### XDRBK Prolog

     NAME       : HCPXDRBK
     DESCRIPTION: Expanded Storage Directory Block
     DSECT      : XDRBK
     FUNCTION   : This block maintains the state of all increments
                  of expanded storage installed on the system.
     LOCATED BY : The pointer to the collection of XDRBKs known
                  as the "directory" is located in field
                  XSTDIRAN of the Expanded Storage Management
                  Data Block (XSTMG).
     CREATED BY : HCPESCDI during initialization processing.
     DELETED BY : HCPESCDI if no expanded storage is configured
                  to the system.

#### XDRBK Control Block Content

#### XDRBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      XDRBK          Expanded Storage Directory Block
    0000    0 Dbl-Word     8 XDRINCDR (4)   Increment Directory Entry
    0000    0 Dbl-Word     8 XDRENTRY (0)   Increment Directory Entry
    0000    0 Signed       4 XDRAEMAP       Address of allocation and error
                                            maps (XSUBK) for this increment.
    0004    4 Signed       4 XDRINDX        Increment index.
    0008    8 Dbl-Word     8 XDRCURNT       Current status of allocation.
    0010   16 Signed       4 XDRINALC       Count of blocks available in the
                                            increment
    0014   20 Signed       4 XDRINERC       Count of blocks in error in the
                                            increment.
    0018   24 Signed       4 XDRFLAGS       Flags and locks for the entry
    001C   28 Signed       4 *              Reserved for IBM use
    0008    8 Signed       4 XDRINCRS       Increment cursor which points to
                                            the next available block to
                                            attempt to allocate within this
                                            increment.
    000C   12 Signed       4 XDRSCLEN       Length of allocation map left to
                                            scan. It is the number of bytes
                                            between XDRINCRS and the end of
                                            the allocation map.
    0010   16 Signed       4 XDRVMDBK       Address of the base VMDBK which
                                            owns this increment of xstore.
                                            This base VMDBK is the base for
                                            the primary configuration for
                                            this user. It is equivalent to
                                            VMDORIG. This field is valid if
                                            XDRSTAT is in the Guest and not
                                            Migrating state.
    0018   24 Signed       2 XDRLOCK        Lock area for this increment
    001A   26 Bitstring    1 XDRSTAT        Increment status flag byte
              1... ....      XDRCONFG       X'80' Increment is configured to
                                            this hardware partition.
              .1.. ....      XDRSTDBY       X'40' Increment is in standby
                                            mode
              ..1. ....      XDRRESVD       X'20' Increment is in reserved
                                            mode
              .... 1...      XDRONLIN       X'08' Increment is logically
                                            online and usable. When this bit
                                            is on, the XSUBK address in
                                            XDRAEMAP can be used. When this
                                            bit is off, all the blocks
                                            associated with this XDRBK are in
                                            error despite the contents of the
                                            allocation and error maps.
              .... ..1.      XDRCP          X'02' Increment belongs to CP.
                                            When off the increment belongs to
                                            a guest.
              .... ...1      XDRINCMD       X'01' Increment state modifier.
                                            When on: If XDRCP is on then
                                            increment is in the CP-Retained
                                            state. If XDRCP is off then
                                            increment is in the
                                            Guest-Migrating state.
    001B   27 Bitstring    1 *              Reserved for IBM use
    0018   24 Bitstring    1 XDRINCLK       This is the lock byte for the
                                            increment. The lock must be
                                            obtained to scan for a block
                                            within the increment.
    0019   25 Bitstring    1 XDROWNER       This is the lock owner identifier
                                            field.
              000000E3       XDRATTCH       X'E3' Attach owns the lock
              000000D9       XDREPAIR       X'D9' Usability map repair owns
                                            lock
              000000D8       XDRQUERY       X'D8' Query XSTORE owns the lock
              000000D5       XDRETAIN       X'D5' Retain XSTORE owns the lock
              000000D4       XDRMCH         X'D4' Machine Check Handler owns
                                            lock
              000000C5       XDRDETCH       X'C5' Detach owns the lock
              000000C4       XDRDEALC       X'C4' Deallocation owns the lock
              00000000       XDRALLOC       X'00' If XDRINCLK is set,
                                            allocation owns the lock. If
                                            XDRINCLK is not set then no
                                            owner.
              00000020       XDRLENTH       *-XDRBK Length of each XDRBK in
                                            bytes
              00000004       XDRSIZE        (*-XDRBK+7)/8 Length of each
                                            XDRBK in dwords

#### XDRBK Storage Layout

    *** XDRBK - Expanded Storage Directory Block
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       XDRINCDR                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  20
    *
    *** XDRBK - Expanded Storage Directory Block

    *** Overlay for XDRINCDR in XDRBK
    *
    *     +---------------------------+---------------------------+
    *   0 |         XDRAEMAP          |         XDRINDX           |
    *     +---------------------------+---------------------------+
    *   8 |                       XDRCURNT                        |
    *     +---------------------------+---------------------------+
    *  10 |         XDRINALC          |         XDRINERC          |
    *     +---------------------------+---------------------------+
    *  18 |         XDRFLAGS          |///////////////////////////|
    *     +---------------------------+---------------------------+
    *  20
    *
    *** Overlay for XDRINCDR in XDRBK

    *** Overlay for XDRCURNT in XDRBK
    *
    *     +---------------------------+---------------------------+
    *   8 |         XDRINCRS          |         XDRSCLEN          |
    *     +---------------------------+---------------------------+
    *  10
    *
    *** Overlay for XDRCURNT in XDRBK

    *** Overlay for XDRINALC in XDRBK
    *
    *     +---------------------------+
    *  10 |         XDRVMDBK          | 14
    *     +---------------------------+
    *
    *** Overlay for XDRINALC in XDRBK

    *** Overlay for XDRFLAGS in XDRBK
    *
    *     +-------------+------+------+
    *  18 |  XDRLOCK    |:STAT |//////| 1C
    *     +-------------+------+------+
    *
    *** Overlay for XDRFLAGS in XDRBK

    *** Overlay for XDRLOCK in XDRBK
    *
    *     +------+------+
    *  18 |:INCLK|:OWNER| 1A
    *     +------+------+
    *
    *** Overlay for XDRLOCK in XDRBK

#### XDRBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    XDRAEMAP       0000
    XDRALLOC       0019 00000000
    XDRATTCH       0019 000000E3
    XDRCONFG       001A 80
    XDRCP          001A 02
    XDRCURNT       0008
    XDRDEALC       0019 000000C4
    XDRDETCH       0019 000000C5
    XDRENTRY       0000
    XDREPAIR       0019 000000D9
    XDRETAIN       0019 000000D5
    XDRFLAGS       0018
    XDRINALC       0010
    XDRINCDR       0000
    XDRINCLK       0018
    XDRINCMD       001A 01
    XDRINCRS       0008
    XDRINDX        0004
    XDRINERC       0014
    XDRLENTH       0019 00000020
    XDRLOCK        0018
    XDRMCH         0019 000000D4
    XDRONLIN       001A 08
    XDROWNER       0019
    XDRQUERY       0019 000000D8
    XDRRESVD       001A 20
    XDRSCLEN       000C
    XDRSIZE        0019 00000004
    XDRSTAT        001A
    XDRSTDBY       001A 40
    XDRVMDBK       0010

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 17:41:43 EDT.
Copyright IBM Corporation, 1990, 2005