SASBK | Back to Index page

| Prolog Control Block Contents SASBK DSECT SASEDATA 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.

SASBK Prolog | Top of page

     NAME       : HCPSASBK
     DESCRIPTION: Saved Segments Data Array
     DSECT      : SASBK
     FUNCTION   :
                  Defines a fixed-length array containing data about
                  saved segments during a live guest relocation
     LOCATED BY :
                  Source system -
                  Transient area, accessed only within HCPRLLSE
                  Destination system -
                  The RLOSSEGS field of the RLOBK
     CREATED BY :
                  Source system -
                  HCPRLLSE during source system eligibility checking.
                  Destination system -
                  HCPRLLDE during destination system eligibility
                  checking.
     DELETED BY :
                  Source system -
                  HCPRLLSE after completing source eligibility
                  checking.
                  Destination system -
                  HCPRLNCT during destination system STMGT cleanup.
     REFERENCES :
                  None.
     SERIALIZED :
                  An SASBK is created on the source system once during
                  each relocation, and once created is never updated.
                  It is destroyed by HCPRLLSE (Source system storage
                  eligibility checking) at the close of the initial set
                  of eligibility checks.
                  The SASBK is sent to the destination system where it
                  is used by one task at a time, either HCPRLLDE
                  (Destination system storage eligibility checking)
                  or by HCPRLLCS (Create guest address spaces), neither
                  of which update the block.  On the destination, the
                  SASBK is released only by HCPRLNCT (Cleanup routine
                  for LGR Memory Move - Target System).
                  Changes to the guest's NSS or DCSS configuration
                  cannot be made during a relocation; DIAG x'64'
                  LOAD/UNLOAD and the IPL command will fail a
                  relocation in progress.
     RELOCATION CONSIDERATIONS : This block is sent from the source to the
                  destination system.
     NOTES      :
                  None.

SASBK Control Block Content | Top of page

     SASBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SASBK          Saved Segments Data Array
                 The following is header information for the array.
    0000    0 Character    8 SASBKNAM       (+00) Indicate start of the
                                            SASBK. This is an eyecatcher,
                                            'SASBK=>', and is used to ID
                                            this block. On the destination,
                                            ISFC allocates this block as free
                                            storage, and as such it will lack
                                            a trailer.
    0008    8 Signed       2 SASCOUNT       (+08) Ct. of segs loaded on the
                                            user
    000A   10 Bitstring    1 SASTYPES       (+0A) Types of segs in this
                                            relocation
              .... ..1.      SASDCSS        X'02' SASDCSS We're migrating at
                                            least one DCSS
              .... ...1      SASNSS         X'01' SASNSS We're migrating an
                                            NSS
    000B   11 Bitstring    5 *              (+0B) Reserved for IBM use
              00000010       SASHDEND       * Mark the end of the header
              00000010       SASHDSIZ       *-SASBK Byte size of the SASBK
                                            header
              00000002       SASHDSZD       (SASHDSIZ+7)/8 DWORD size of the
                                            SASBK header
                 Start of the variable data section of the array.

     SASEDATA DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SASEDATA       Saved Segments Data Array
    0000    0 Signed       2 SASEHEAD (0)   (+00) Start of a data entry
    0000    0 Character    8 SASENAME       (+00) Name of this segment
    0008    8 Character    8 SASETYPE       (+08) Filetype of this segment
    0010   16 Bitstring    1 SASESBCD       (+10) Flags for this segment
              .... .1..      SASENSHR       X'04' SASENSHR This is an
                                            exclusive copy of a DCSS
              .... ..1.      SASENSS        X'02' SASENSS This is an NSS
              .... ...1      SASGT2G        X'01' SASGT2G This is a segment
                                            loaded > 2G
    0011   17 Bitstring    3 *              (+11) Reserved for IBM use
    0014   20 Bitstring   20 SASCHKSM       (+14) SHA-1 segment checksum
    0028   40 Bitstring    8 *              (+28) Reserved for IBM use
              00000030       SASENEXT       * Address of the next SAS entry
              00000030       SASENTLN       *-SASEDATA Byte length of a data
                                            entry
              00000006       SASENLND       (SASENTLN+7)/8 DWORD length of a
                                            data entry

SASBK Storage Layout | Top of page

    *** SASBK - Saved Segments Data Array
    *
    *     +-------------------------------------------------------+
    *   0 |                       SASBKNAM                        |
    *     +-------------+------+----------------------------------+
    *   8 |  SASCOUNT   |:TYPES|//////////////////////////////////|
    *     +-------------+------+----------------------------------+
    *  10
    *
    *** SASBK - Saved Segments Data Array

    *** SASEDATA - Saved Segments Data Array
    *
    *     +-------------------------------------------------------+
    *   0 |                       SASENAME                        |
    *     +-------------------------------------------------------+
    *   8 |                       SASETYPE                        |
    *     +------+--------------------+---------------------------+
    *  10 |:ESBCD|////////////////////|                           |
    *     +------+--------------------+                           |
    *     |                       SASCHKSM                        |
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  28 |///////////////////////////////////////////////////////|
    *     +-------------------------------------------------------+
    *  30
    *
    *** SASEDATA - Saved Segments Data Array

SASBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    SASBKNAM       0000
    SASCHKSM       0014
    SASCOUNT       0008
    SASDCSS        000A 02
    SASEHEAD       0000
    SASENAME       0000
    SASENEXT       0028 00000030
    SASENLND       0028 00000006
    SASENSHR       0010 04
    SASENSS        0010 02
    SASENTLN       0028 00000030
    SASESBCD       0010
    SASETYPE       0008
    SASGT2G        0010 01
    SASHDEND       000B 00000010
    SASHDSIZ       000B 00000010
    SASHDSZD       000B 00000002
    SASNSS         000A 01
    SASTYPES       000A

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:30:08 EDT.
Copyright IBM Corporation, 1990, 2020