GVSBK Back to Index page
 
Prolog 
Control Block Contents 
   GVSBK DSECT
   GVSENBK DSECT
   GVSMBK 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.


  GVSBK Prolog Top of page
 
 NAME       : HCPGVSBK
 DESCRIPTION: Global VSwitch Manager Block
 DSECT      : GVSBK
 FUNCTION   :
              This block maintains a list of Global VSwitches defined
              on a local z/VM image.  Each Global VSwitch within the
              list contains information for each active IVL Member
              which has an instance of the VSwitch defined on its
              system.
  NCHORED BY -
              HCPLANGV = Contains Address for the L:GVSBK
 CREATED BY :
              HCPIVSCR when an IVL VSwitch is first defined for
              the z/VM system.
 DELETED BY :
              The GVSBK is never deleted once created.  Although its
              lock will be destroyed if the IVL VSwitch is DETACHED.
              See "Notes" for additional information.
 SERIALIZED :
              The GVSHLOCK is used to serialize fields within the
              L:GVSBK (header) and to add, remove and modify Global
              VSwitch entities (GVSENBK).
              The LANLKWRD is used to serialize fields in the local
              system's VSwitch Member entry (GVSMBK).
 RELOCATION CONSIDERATIONS : None
 COMPATIBILITY AND MIGRATION CONCERNS : N/A.
 NOTES      :
              Individual Global VSwitch entities (GVSENBKs) are added
              by DEFINE VSWITCH (GLOBAL) and deleted by DETACH
              VSWITCH (GLOBAL). The L:GVSENBK for a given VSwitch is
              anchored in the LANBK (LANGVSENBK).
 
 
  GVSBK Control Block Content Top of page
 

 GVSBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure GVSBK Global VSwitch Manager Block EQUATES 00000010 GVSMMAX 16 Maximum Global VSwitch Members per Global VSwitch The Global VSwitch Manager Block 0000 0 Dbl-Word 8 GVSHLKST (0) Start displacement for block clear 0000 0 Dbl-Word 8 GVSHLOCK (3) GVSBK Header Lock-word 0018 24 Address 4 GVSHLPTR Ptr to Global VSwitch Array header 001C 28 Signed 4 * Reserved for future IBM use 0020 32 Dbl-Word 8 * Reserved for future IBM Use 00000005 GVSHSIZ (*-GVSBK+7)/8 Size in double words 00000028 GVSHBSIZ GVSHSIZ*8 Size in bytes Global VSwitch Linked List The Global VSwitch Linked List Structure - Global VSwitch entities (GVSENBK) - Up to 16 VSwitch Member Array (GVSMBK) entries per parent Global VSwitch entity. - Each VSwitch Array entry represents a single VSwitch instance that is a member of the parent Global VSwitch. GVSBK +----------+ | GVSHLOCK | GVSENBK GVSENBK | GVSHLPTR |---->+---------------+ +---------------+ +----------+ +->| GVSEHFP |--->| GVSEHFP = 0 | HCPLANBK | | GVSEHBP = 0 |<---| GVSEHBP | +-----------+ | | GVSENAME | | GVSENAME | | LANGVSENBK|-+ |---------------| |---------------| +-----------+ |(1)GVSMBK | |(1)GVSMBK | | ! ----- | | ! ----- | | ! GVSMSN | | ! GVSMSN | | ! GVSMSTAT | | ! GVSMSTAT | | ! . | | ! . | | ! . | | ! . | | V | | V | |(16)GVSMBK | |(16)GVSMBK | | ------ | | ------ | | GVSMSN | | GVSMSN | | GVSMSTAT | | GVSMSTAT | +---------------+ +---------------+ Serialized : LAN Lock (LANLKWRD) - The LAN Lock (LANLKWRD) serializes the DEFINE, SET STATE and membership of a GLOBAL VSwitch which is represented as a Global VSwitch Array entry. GVSBK Header Lock (GVSHLOCK) - The GVSBK Header Lock (GVSHKWRD) serializes the addition and deletion of Global VSwitch Array entries. Global VSwitch Array Entity The Global VSwitch Array Entity: A single Global VSwitch entity and its imbedded VSwitch Member Array. This Global VSwitch entity is linked to all known Global VSwitch entities discovered by the local Global VSwitch Manager.
 GVSENBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure GVSENBK Global VSwitch Manager Block 0000 0 Address 4 GVSEHFP L:next Global VSwitch Entity block 0004 4 Address 4 GVSEHBP L:prev Global VSwitch Entity block 0008 8 Character 8 GVSENAME Name of Global VSwitch 0010 16 Bitstring 1 GVSELAST Index to last VSwitch Member Entry 0011 17 Character 1 * (7) Reserved for future IBM Use Local VSwitch Member Area - Currently supports 16 VSwitch members per Global VSwitch (Global VSwitch Array Entry). The memory allocated needs to contain a potential maximum of 16 VSwitch Member entries. 0018 24 Bitstring 256 GVSVMEMB Memory for the maximum number of VSwitch Member Arrays. 00000023 GVSESIZE (*-GVSENBK+7)/8 Size in double words 00000118 GVSEBSZE GVSESIZE*8 Size in bytes VSwitch Member Entry The VSwitch member entry represents a particular VSwitch that is a member of a the Global VSwitch represented by the Global VSwitch Entry. The current limit of 16 LPARs supported for the IVL LAN segment insures that the total number of VSwitch Member entries will not exceed 16. NOTES : If the VSwitch member entry is expanded beyond 16 bytes, then the GVSVMEMB area must also be increased to accommodate the growth for 16 entries.
 GVSMBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure GVSMBK Global VSwitch Manager Block 0000 0 Character 8 GVSMSN System name for member VSwitch 0008 8 Signed 4 GVSMREAS ERROR State Reason Message Number 000C 12 Bitstring 1 GVSMSTAT Global VSwitch Handler State machine representing the synch state of the VSwitch member 00000000 GVSMSTAT_OUTOFSYNC X'00' GVSMSTAT_OUTOFSYNC - Member is not in sync Global VSwitch attributes 00000050 GVSMSTAT_ERROR X'50' GVSMSTAT_ERROR - Member is in an error sta 00000060 GVSMSTAT_PENDING X'60' GVSMSTAT_PENDING - Member is in pending sy state (transitional state) 000000F0 GVSMSTAT_INSYNC X'F0' GVSMSTAT_INSYNC - Member attributes in syn with Global VSwitch attributes 000D 13 Bitstring 3 * Reserved for future IBM Use 00000002 GVSMSIZE (*-GVSMBK+7)/8 Size in double words 00000010 GVSMBSZE GVSMSIZE*8 Size in bytes
 
 
  GVSBK Storage Layout Top of page
 
          
*** GVSBK - Global VSwitch Manager Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       GVSHLOCK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  18 |         GVSHLPTR          |///////////////////////////|
*     +---------------------------+---------------------------+
*  20 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  28
*
*** GVSBK - Global VSwitch Manager Block
          
*** GVSENBK - Global VSwitch Manager Block
*
*     +---------------------------+---------------------------+
*   0 |         GVSEHFP           |         GVSEHBP           |
*     +---------------------------+---------------------------+
*   8 |                       GVSENAME                        |
*     +------+------------------------------------------------+
*  10 |:ELAST|////////////////////////////////////////////////|
*     +------+------------------------------------------------+
*  18 |                                                       |
*     =                       GVSVMEMB                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 118
*
*** GVSENBK - Global VSwitch Manager Block
          
*** GVSMBK - Global VSwitch Manager Block
*
*     +-------------------------------------------------------+
*   0 |                        GVSMSN                         |
*     +---------------------------+------+--------------------+
*   8 |         GVSMREAS          |:MSTAT|////////////////////|
*     +---------------------------+------+--------------------+
*  10
*
*** GVSMBK - Global VSwitch Manager Block
 
 
  GVSBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
GVSEBSZE       0018 00000118
GVSEHBP        0004
GVSEHFP        0000
GVSELAST       0010
GVSENAME       0008
GVSESIZE       0018 00000023
GVSHBSIZ       0020 00000028
GVSHLKST       0000
GVSHLOCK       0000
GVSHLPTR       0018
GVSHSIZ        0020 00000005
GVSMBSZE       000D 00000010
GVSMMAX        0000 00000010
GVSMREAS       0008
GVSMSIZE       000D 00000002
GVSMSN         0000
GVSMSTAT       000C
GVSMSTAT_ERROR
               000C 00000050
GVSMSTAT_INSYNC
               000C 000000F0
GVSMSTAT_OUTOFSYNC
               000C 00000000
GVSMSTAT_PENDING
               000C 00000060
GVSVMEMB       0018
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:51:00 EDT.
Copyright IBM Corporation, 1990, 2022