PGLBK | Back to Index page

| Prolog Control Block Contents PGLBK DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

PGLBK Prolog | Top of page

     NAME       : HCPPGLBK
     DESCRIPTION: Page List Block
     DSECT      : PGLBK
     FUNCTION   : Contains a list of PTE addresses that
                  comprise a paging block on the destination
                  system during a Live Guest Relocation
     LOCATED BY : Passed as a parameter from the Memory Move Receive
                  Loop (HCPRLBRC) to the DASD Handler (HCPDOPMW)
     CREATED BY : HCPRLBRC - VMRELOCATE Memory Move Receive Loop on
                  the destination system
     DELETED BY : HCPDOPMW - VMRELOCATE Write pages to DASD on
                  the destination system
     SERIALIZED : Local task serialization
     RELOCATION CONSIDERATIONS : None
     COMMENTS   : The size of this list is variable. HCPRLBRC will
                  allocate enough space to hold a PTE address for
                  every guest address passed from the source system
                  in a "pages on DASD" Memory Move ISFC message.
                  The order of the PTE addresses in the PGLBK
                  corresponds to the order of the 4K buffer
                  addresses passed in the 2nd-Nth message fragments
                  of the ISFC message.
                  HCPRLBRC may not fill the entire PGLBK:
                  1) If a page included in the ISFC message is a
                  state-change only, then no page content needs to be
                  written for this page. (This should be rare, only
                  occurring for a PGSERROR condition on the
                  source system.)
                  2) If HCPRLBRC cannot obtain PTE serialization,
                  the corresponding PTE entry in the PGLBK will remain
                  zero and the page will not be included in the paging
                  block. When HCPDOPMW finds a zero PTE address in the
                  PGLBK it skips the corresponding buffer address in
                  the ISFC message.

PGLBK Control Block Content | Top of page

     PGLBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      PGLBK          Page List Block
    0000    0 Dbl-Word     8 PGLPTEAD       PTE address (or zero if page
                                            serialization could not be
                                            obtained)
              00000008       PGLENTLN       *-PGLBK Length of one entry
    0008    8 Dbl-Word     8 PGLNXENT (0)   Next PTE address in list
          End of PGLBK

PGLBK Storage Layout | Top of page

    *** PGLBK - Page List Block
    *
    *     +-------------------------------------------------------+
    *   0 |                       PGLPTEAD                        |
    *     +-------------------------------------------------------+
    *
    *** PGLBK - Page List Block

PGLBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    PGLENTLN       0000 00000008
    PGLNXENT       0008
    PGLPTEAD       0000

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:29:37 EDT.
Copyright IBM Corporation, 1990, 2020