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



Control Block Contents  

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

PPDBK Prolog

 Name       : HCPPPDBK
 Description: Paged PGMBK Data block
 Function   : A PPDBK contains information required to find
              and process an STE corresponding to a paged
              PGMBK (PTRM page) which has been paged to DASD.
 Located by : The PPDBK address is saved in the invalid PTRM PTE
              for PTRM pages (paged PGMBKs) that reside on DASD.
              The address is saved in a hashed format so that the
              Invalid and Page Protect bits of the PTRM PTE are
              left undisturbed; HCPISTEA macro is used to insert
              the PPDBK address into the PTRM PTE, HCPGSTEA macro
              is used to extract the PPDBK address from the PTRM
 Created by : HCPPRPOP/HCPHRPOP when a PTRM page is invalidated,
              in preparation for the PTRM page (pageable PGMBK)
              potentially being paged to DASD.
              HCPMIPRB/HCPPMPRB when a PTRM page (paged PGMBK) is
              migrated from expanded storage to DASD.
              HCPPRUSM/HCPHRUSM when processing a segment table
              relocation, and a PTRM page (pageable PGMBK) on
              DASD, but without a PPDBK address in the PTRM PTE,
              is encountered.
 Deleted by : HCPPTUPF/HCPHTUPF when a PTRM page (paged PGMBK) is
              is read in from DASD.
              HCPPTAQA when a PTRM page (pageable PGMBK) is paged
              to expanded storage instead of DASD.
 Serialized :
              Serialized by PTRM PTE serialization, though to use
              or change the PPDSTE field, (at least) a share of
              VMDPTIL on the virtual configuration that owns the
              the corresponding segment table entry is required,
              to serialize against concurrent destructive changes
              to the segment table (such as segment table relocate
              for resize during NSS/DCSS imbed/unimbed).
 Comments   :


PPDBK Control Block Content


Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      PPDBK          Paged PGMBK Data block
0000    0 Address      4 PPDSTE         Address of STE corresponding to
                                        paged PGMBK
0004    4 Address      4 PPDVMDBK       Address of the owning vconfig's
                                        base VMDBK
          00000008       PPDBKLEN       *-PPDBK Size of one PPDBK in
          00000001       PPDBKSIZ       ((*-PPDBK)+7)/8 Size of one PPDBK
                                        in dws
     End of PPDBK definitions


PPDBK Storage Layout

*** PPDBK - Paged PGMBK Data block
*     +---------------------------+---------------------------+
*   0 |          PPDSTE           |         PPDVMDBK          |
*     +---------------------------+---------------------------+
*   8
*** PPDBK - Paged PGMBK Data block


PPDBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
PPDBKLEN       0004 00000008
PPDBKSIZ       0004 00000001
PPDSTE         0000
PPDVMDBK       0004

This information is based on z/VM V4R3.0. Last updated on 30 Apr 2002 at 17:20:51 EDT.
Copyright IBM Corporation, 1990, 2002