NAME       : HCPSDNX
 DESCRIPTION: State Description Annex
 DSECT      : SDNX
 FUNCTION   : Maps the State Description Annex
 LOCATED BY : SIESDNXD field in SIEBK (host real)
 CREATED BY : HCPSDN when a guest first attempts to use a
              feature requiring an SD annex.
 DELETED BY : HCPSDN during RESET CLEAR, LOGOFF or DETACH
              CPU processing
 REFERENCES : None
 SERIALIZED :
 RELOCATION CONSIDERATIONS : This control block is relocated as part of a live
              guest relocation (LGR). The bits and fields that
              need to be relocated are defined in the
              corresponding LGRSDNX COPY file. Whenever changes
              are made to this control block, consideration must
              be given to any effects these changes will have on
              a relocation. If any new fields or bits are
              defined, they may need to be relocated. If
              existing bits or fields are changed, corresponding
              modifications may be required in the LGR version of
              this control block. Consider also the effects of
              these changes on a relocation involving a back-level
              release of CP.
 COMPATIBILITY AND MIGRATION CONCERNS : The format of this control block is defined by the
              z/Architecture CPU Architecture.
 GENERAL NOTES      : Although the architecture defines the minimum size
              for an SD annex to be 64 bytes, this implementation
              uses a minimum of 256 bytes so as to ensure cache-
              line alignment.

 SDNX DSECT
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Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      SDNX           State Description Annex
      The first eight bytes of the SDNX are defined as 'Reserved
      for Program Use'. We use the first four bytes as an eye-
      catcher, and the second four bytes to hold the host logical
      address of the owning VMDBK.
0000    0 Bitstring    8 SDNXPROG (0)   Program use area
0000    0 Character    4 SDNXEYE        Eyecatcher: 'SDNX'
0004    4 Address      4 SDNXVMD        HLA of owning VMDBK
0008    8 Bitstring   56 SDNXSYSA (0)   System use area
0008    8 Bitstring    8 *              Reserved
      Feature control blocks. Add new ones to the list as
      necessary.
0010   16 Bitstring   32 SDNXGSCB       Guarded-Storage Control Block
      IBM Reservered Area 1
0030   48 Bitstring   16 SDNXIBM1       Reserved for IBM use
      The next statement must appear after all of the feature
      control blocks.
          00000040       SDNXDLEN       *-SDNX Length of defined data
      The architecture requires the State Description Annex to
      have a length that is a power of two, the minimum being 64
      and the maximum 4096. We assign a minimum of 256 bytes so
      as to ensure cache-line alignment.
      These values define the control block sizes that will be
      allocated by CP.
          00000008       SDNXC          8 Characteristic: 2**8 = 256
          00000020       SDNXSIZE       32 SDNX size in doublewords
0040   64 Bitstring    1 *              Pad to 256-byte boundary

          
*** SDNX - State Description Annex
*
*     +---------------------------+---------------------------+
*   0 |         SDNXEYE           |         SDNXVMD           |
*     +---------------------------+---------------------------+
*   8 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  10 |                                                       |
*     =                       SDNXGSCB                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  30 |                       SDNXIBM1                        |
*     |                                                       |
*     +------+------------------------------------------------+
*  40 |//////|////////////////////////////////////////////////|
*     +------+////////////////////////////////////////////////|
*  48 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
* 100
*
*** SDNX - State Description Annex

 
Symbol         Dspl Value
-------------- ---- -----
SDNXC          0030 00000008
SDNXDLEN       0030 00000040
SDNXEYE        0000
SDNXGSCB       0010
SDNXIBM1       0030
SDNXPROG       0000
SDNXSIZE       0030 00000020
SDNXSYSA       0008
SDNXVMD        0004