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

NSUBK

Prolog  

Control Block Contents  
   NSUBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


NSUBK Prolog

 NAME       : HCPNSUBK
 DESCRIPTION: Auxillary Storage Management utility data
 DSECT      : NSUBK
 FUNCTION   : This block will map the ASM data module HCPNSUDA.
 LOCATED BY : This block is located in HCPNSUDA.
 NOTES      :
                  Data Queue Definitions
                  ----------------------
  Saved Segment SNTBK queue: The Saved Segment SNTBK queue is
  a list of SNTBKs that represents each DCSS and Segment Space
  that is currently loaded by at least one user. Its header
  is NSUSGQAN.
  Named Saved System SNTBK queue: The Named Saved System SNTBK
  queue is a list of SNTBKs that represents each Named Saved
  System that is IPL'd by at least one user. Its header is
  NSUSYQAN.
  *NSS SDF queue: The *NSS SDF queue is a list of all Saved
  Segment and Named Saved System SDF files. Whenever a Saved
  Segment or Named Saved System is defined a spool file is
  created and put onto this queue. When the first DIAG X'64'
  Load or CP IPL command is processed for the Saved Segment
  or Named Saved System, the SDF file is opened, the SNTBK
  description page is read into storage and put onto the
  Saved Segment SNTBK or Named Saved System SNTBK queue
  respectively. If the Saved Segment is a member segment then
  the Segment Space SNTBK will be put onto the Saved Segment
  SNTBK queue. The SDF file remains open for read as long as
  at least one user has the Saved Segment loaded or the Named
  Saved System IPLed. The header of the *NSS SDF queue is
  located in the FILID table (reserved entry *NSS).
  VMDBK/SHRBK queue: The VMDBK/SHRBK is a queue of SHRBKs
  that represents a DIAG X'64' Load or CP IPL command for
  the owner of the VMDBK. Each time a Saved Segment or Named
  Saved System is loaded a SHRBK is added to this queue. It
  is removed by a DIAG X'64' Purge request or a system reset.
  The header of the VMDBK/SHRBK is VMDSHRPT.
  SNTBK/SHRBK queue: The SNTBK/SHRBK is a queue of SHRBKs that
  represents a DIAG X'64' Load or CP IPL command for this
  Saved Segment or Named Saved System. Each time a Saved
  Segment or Named Saved System is loaded a SHRBK is added to
  this queue. It is removed by a DIAG X'64' Purge request or
  a system reset. The header of the SNTBK/SHRBK is SNTSHRPT.
  SAVESEG SNTBK queue: The SAVESEG SNTBK queue is a list of
  SNTBKs that represents each Saved Segment that is currently
  being saved. This queue should be referenced by any CP
  function (such as Query or Purge NSS) that needs to obtain
  information about a Saved Segment that is currently being
  saved. The header of the SAVESEG queue is NSUSSGAN.
  SAVESYS SNTBK queue: The SAVESYS SNTBK queue is a list of
  SNTBKs that represents each Named Saved System that is
  currently being saved. This queue should be referenced by
  any CP function (such as Query or Purge NSS) that needs to
  obtain information about a Named Saved System that is
  currently being saved. The header of the SAVESYS queue is
  NSUSSYAN.
  Lock Hierarchy for Saved Segment or Named Saved System
  ------------------------------------------------------
  Level 1 Locks: VMDBK/SHRBK queue lock (VMDSHRLK)
                 DEFSEG/SAVESEG exclusive command lock
                   (NSUDSGLK)
                 DEFSYS/SAVESYS symbolic command lock
                   (NSUDSYAN)
  Level 2 Lock:  *NSS SDF queue lock (NSUSDFLK)
  Level 3 Lock:  Named Saved System SNTBK queue lock
                 (NSUSYQLK)
  Level 4 Lock:  Saved Segment SNTBK queue lock (NSUSGQLK)
  Level 5 Lock:  SNTBK/SHRBK queue lock (SNTSHRLK) for one of
                   Member Saved Segment, DCSS, or Named Saved
                   System
  Level 6 Lock:  SNTBK/SHRBK queue lock (SNTSHRLK) for Segment
                   Space
  Note: 1) The level 1 locks are the hightest level locks and
           the level 6 locks are the lowest level locks.
        2) If locks need to be obtained from different levels,
           then the higher level lock needs to be obtained
           first.
        See the definition and description of each individual
        lock for more detailed information.
  Saved Segment or Named Saved System serialization matrix
  --------------------------------------------------------
          +-----------------+-----+-----+-----+-----+-----+
          |      LVL1       | LVL2| LVL3| LVL4| LVL5| LVL6|
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  | Func- | VMD | Def | Def | *NSS| NSS | Sseg| SNT | SNT |
  | tion  | SHR | Save| Save| SDF |  Q  |  Q  | SHR | SHR |
  |       |  Q  | seg | SYS |  Q  | lock| lock|  Q  |  Q  |
  |       | lock| cmd | cmd | lock|     |     | Lock| Lock|
  |       |     | lock| lock|     |     |     |     |(SSP)|
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DEFSEG |     | exc |     | exc |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |SAVESEG|     | exc |     | exc |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64|     |     |     |     |     | shr |     |     |
  |Find-1 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64|     |     |     | exc |     |     |     |     |
  |Find-2 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64| exc |     |     |     |     | shr | exc | exc |
  |Load-1 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64| exc |     |     | exc |     | exc |     |     |
  |Load-2 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64| exc |     |     |     |     | shr | exc | exc |
  |Purge1 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DIAG 64| exc |     |     | exc |     | exc |     |     |
  |Purge2 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Q NSS  |     |     |     | exc |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Q NSS  |     |     |     |     | shr | shr | shr | shr |
  |USERS  |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Inter  | exc |     |     |     | shr | shr | exc | exc |
  |Purge-1|     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Inter  | exc |     |     | exc | exc | exc |     |     |
  |Purge-2|     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |DEFSYS |     |     | exc | exc |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |SAVESYS|     |     | exc | exc |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  | IPL   | exc |     |     | shr | shr |     | exc |     |
  | NSS-1 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  | IPL   | exc |     |     | exc | exc |     |     |     |
  | NSS-2 |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Monitor|     |     |     |     | shr | shr |     |     |
  |Sample |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Monitor| shr |     |     |     |     |     |     |     |
  | IUCV  |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  | Purge |     |     |     | exc | exc | exc |     |     |
  | Cmd   |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  | Indi- |     |     |     |     | shr | shr |     |     |
  | cate  |     |     |     |     |     |     |     |     |
  | NSS   |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |VMdump | exc |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  |Mig-   |     |     |     |     | shr | shr |     |     |
  |rator  |     |     |     |     |     |     |     |     |
  +-------+-----+-----+-----+-----+-----+-----+-----+-----+
  Notes:
  DIAG 64 Find-1 : Find a Saved Segment from the Saved Segment
                   SNTBK queue
  DIAG 64 Find-2 : Find a Saved Segment from the *NSS SDF
                   queue
  DIAG 64 Load-1 : Load a Saved Segment from the Saved Segment
                   SNTBK queue.
  DIAG 64 Load-2 : Load a Saved Segment from the *NSS SDF
                   queue
  DIAG 64 Purge1 : 'use-count' > 1, not the last user.
  DIAG 64 Purge2 : 'use-count' = 1, last user of the Saved
                   Segment.
  Inter Purge-1  : 'Internal' Purge, 'use-count' > 1, not the
                   last user.
  Inter Purge-2  : 'Internal' Purge, 'use-count' = 1, last
                   user of the Saved Segment.
  IPL NSS-1      : IPLing a Named Saved System from the Named
                   Saved System SNTBK queue
  IPL NSS-2      : IPLing a Named Saved System from the *NSS
                   SDF queue

 

NSUBK Control Block Content


NSUBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      NSUBK          Auxillary Storage Management
                                        utility data
              Saved Segment SNTBK Queue lock (NSUSGQLK)
           Lock type: This is a formal shared or exclusive lock
           Resource serialized: This lock will serialize the
           Saved Segment SNTBK queue. The lock will be obtained
           shared when scanning the Saved Segment SNTBK queue
           and exclusive when adding to, or deleting from, the
           queue.
           Notes      : If the *NSS SDF queue lock is held exclusively
           then the Saved Segment SNTBK queue can be scanned
           without holding the queue lock. This is because the
           *NSS SDF queue lock must be held exclusively to add
           or remove a SNTBK from the Saved Segment SNTBK queue.
0000    0 Dbl-Word     8 NSUSGQLK (3)   Shared/exclusive defer lock to
                                        serialize the queue of Saved
                                        Segment SNTBKs anchored at
                                        NSUNSGAN
           Saved Segment SNTBK Queue anchors
0018   24 Dbl-Word     8 NSUNSGAN (0)   Anchors to queue of Saved Segment
                                        SNTBKs
0018   24 Address      4 NSUNSGFW       Foward pointer of Saved Segment
                                        SNTBKs
001C   28 Address      4 NSUNSGBK       Backward pointer of Saved Segment
                                        SNTBKs
             Named Saved System SNTBK Queue lock (NSUSYQLK)
           Lock type: This is a formal shared or exclusive lock
           Resource serialized: This lock will serialize the
           Named Saved System SNTBK queue. The lock will be
           obtained shared when scanning the Named Saved System
           SNTBK queue and exclusive when adding to, or deleting
           from, the queue.
           Notes      : If the *NSS SDF queue lock is held exclusively
           then the Named Saved System SNTBK queue can be scanned
           without holding the queue lock. This is because the
           *NSS SDF queue lock must be held exclusively to add
           or remove a SNTBK from the Named Saved System SNTBK
           queue.
0020   32 Dbl-Word     8 NSUSYQLK (3)   Shared/exclusive defer lock to
                                        serialize the queue of NSS SNTBKs
                                        anchored at NSUNSYAN
            NSS SNTBK Queue anchors
0038   56 Dbl-Word     8 NSUNSYAN (0)   Anchors to queue of NSS SNTBKs.
0038   56 Address      4 NSUNSYFW       Foward pointer of NSS SNTBKs.
003C   60 Address      4 NSUNSYBK       Backward pointer of NSS SNTBKs.
            IMG SNTBK Queue anchors and queue lock
0040   64 Dbl-Word     8 NSUIMGLK (3)   Lockword for image SNTBK queue
                                        lock.
0058   88 Dbl-Word     8 NSUIMGAN (0)   Anchors to image HCPSNTBK queue.
0058   88 Address      4 NSUIMGFW       Foward pointer of HCPSNTBK image
                                        queue.
005C   92 Address      4 NSUIMGBK       Backward pointer of HCPSNTBK
                                        image queue.
            NLS SNTBK Queue anchors and queue lock
0060   96 Dbl-Word     8 NSUNLSLK (3)   Lockword for NLS SNTBK queue
                                        lock.
0078  120 Dbl-Word     8 NSUNLSAN (0)   Anchors to queue of NLS SNTBKs.
0078  120 Address      4 NSUNLSFW       Foward pointer of NLS SNTBKs.
007C  124 Address      4 NSUNLSBK       Backward pointer of NLS SNTBKs.
           Saveseg SNTBK Queue anchors
           Notes      : This queue is serialized by *NSS SDF queue lock
                 NSUSDFLK.
0080  128 Dbl-Word     8 NSUSSGAN (0)   Anchors to queue of SAVESEG
                                        SNTBKs
0080  128 Address      4 NSUSSGFW       Foward pointer of SAVESEG SNTBKs
0084  132 Address      4 NSUSSGBK       Backward pointer of SAVESEG
                                        SNTBKs
           Savesys SNTBK Queue anchors
           Notes      : This queue is serialized by *NSS SDF queue lock
                 NSUSDFLK.
0088  136 Dbl-Word     8 NSUSSYAN (0)   Anchors to queue of SAVESYS
                                        SNTBKs
0088  136 Address      4 NSUSSYFW       Foward pointer of SAVESYS SNTBKs
008C  140 Address      4 NSUSSYBK       Backward pointer of SAVESYS
                                        SNTBKs
0090  144 Signed       4 * (2)          Reserved for future IBM use
           DEFSEG/SAVESEG exclusive command lock (NSUDSGLK)
           Lock type: This is a formal exclusive lock
           Resource serialized: This lock serializes the DEFSEG
           and SAVESEG commands. Only one DEFSEG or SAVESEG
           command can be processed at one time.
0098  152 Dbl-Word     8 NSUDSGLK (3)   Exclusive defer lock to serialize
                                        the DEFSEG/SAVESEG command
           DEFSYS/SAVESYS symbolic command lock (NSUDSYAN)
           Lock type: This is a formal exclusive symbolic name
                      lock.
           Resource serialized: This lock serializes the DEFSYS
           and SAVESYS commands for the Named Saved System that
           is being defined or saved. Only one DEFSYS or SAVESYS
           can be processed for a particular Named Saved System
           at any given time.
00B0  176 Dbl-Word     8 NSUDSYAN       Symbolic queue lock anchor to
                                        serialize the DEFSYS/SAVESYS
                                        command
                    *NSS SDF queue lock (NSUSDFLK)
           Lock type: This is a formal shared or exclusive lock
           Resource serialized: This lock will serialize the
           *NSS SDF queue, the SAVESEG SNTBK queue, and the
           SAVESYS SNTBK queue.
           Functions serialized: This lock must be obtained
           exclusive to open any "*NSS" spool file for read or
           write. It is also used to add or remove SNTBKs from
           the SAVESEG SNTBK queue and the SAVESYS SNTBK queue.
           Notes      : If the *NSS SDF queue lock is held exclusively
           then the Named Saved System SNTBK queue or Saved
           Segment SNTBK queue can be scanned without holding
           the queue lock. This is because the *NSS SDF queue
           lock must be held exclusively to add or remove a
           SNTBK from the Named Saved System SNTBK queue or the
           Saved Segment SNTBK queue.
00B8  184 Dbl-Word     8 NSUSDFLK (3)   Exclusive defer lock to serialize
                                        the queue of SDFs owned by user
                                        *NSS
             SDF multiple symbolic lock manager (NSUMSLKM)
           Lock type: This is a formal exclusive lock
           Functions serialized: This lock will be obtained by
           any CP function (such as "Purge IMG/NLS ALL") that
           needs to obtain multiple symbolic name locks for
           NLS/IMG files.
00D0  208 Dbl-Word     8 NSUMSLKM (3)   Exclusive defer lock to serialize
                                        entry points that obtain multiple
                                        symbolic locks
           IMG/NLS SDF symbolic queue lock anchor
00E8  232 Dbl-Word     8 NSUSYMAN       Symbolic queue lock anchor for
                                        IMG and NLS system data files.

 

NSUBK Storage Layout

          
*** NSUBK - Auxillary Storage Management utility data
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       NSUSGQLK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  18 |         NSUNSGFW          |         NSUNSGBK          |
*     +---------------------------+---------------------------+
*  20 |                                                       |
*     =                       NSUSYQLK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  38 |         NSUNSYFW          |         NSUNSYBK          |
*     +---------------------------+---------------------------+
*  40 |                                                       |
*     =                       NSUIMGLK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  58 |         NSUIMGFW          |         NSUIMGBK          |
*     +---------------------------+---------------------------+
*  60 |                                                       |
*     =                       NSUNLSLK                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  78 |         NSUNLSFW          |         NSUNLSBK          |
*     +---------------------------+---------------------------+
*  80 |         NSUSSGFW          |         NSUSSGBK          |
*     +---------------------------+---------------------------+
*  88 |         NSUSSYFW          |         NSUSSYBK          |
*     +---------------------------+---------------------------+
*  90 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  98 |                                                       |
*     =                       NSUDSGLK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  B0 |                       NSUDSYAN                        |
*     +-------------------------------------------------------+
*  B8 |                                                       |
*     =                       NSUSDFLK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  D0 |                                                       |
*     =                       NSUMSLKM                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  E8 |                       NSUSYMAN                        |
*     +-------------------------------------------------------+
*  F0
*
*** NSUBK - Auxillary Storage Management utility data

 

NSUBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
NSUDSGLK       0098
NSUDSYAN       00B0
NSUIMGAN       0058
NSUIMGBK       005C
NSUIMGFW       0058
NSUIMGLK       0040
NSUMSLKM       00D0
NSUNLSAN       0078
NSUNLSBK       007C
NSUNLSFW       0078
NSUNLSLK       0060
NSUNSGAN       0018
NSUNSGBK       001C
NSUNSGFW       0018
NSUNSYAN       0038
NSUNSYBK       003C
NSUNSYFW       0038
NSUSDFLK       00B8
NSUSGQLK       0000
NSUSSGAN       0080
NSUSSGBK       0084
NSUSSGFW       0080
NSUSSYAN       0088
NSUSSYBK       008C
NSUSSYFW       0088
NSUSYMAN       00E8
NSUSYQLK       0020

This information is based on z/VM V5R1.0. Last updated on 8 Sep 2004 at 14:10:45 EDT.
Copyright IBM Corporation, 1990, 2004