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.
   SPTape SNTBK queue: The SPTape SNTBK queue is a list of
   SNTBKs that represents each unloadable Named Saved System or
   Saved Segment that is currently being SPTape dumped. This
   queue should be referenced by any CP function (such as
   Query or Purge NSS) that needs to obtain information about
   a Saved Segment or Named Saved System that is currently
   being SPTape dumped. The header of the SPTape SNTBK queue
   is NSUSPTAN.
   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  |     |     |     |     |     |     |     |     |
   +-------+-----+-----+-----+-----+-----+-----+-----+-----+
   |SPTape | exc |     |     | exc | exc | exc |     |     |
   | Dump  |     |     |     |     |     |     |     |     |
   +-------+-----+-----+-----+-----+-----+-----+-----+-----+
   |SPTape |     |     |     |     |     |     |     |     |
   | load  |     |     |     |     |     |     |     |     |
   +-------+-----+-----+-----+-----+-----+-----+-----+-----+
   | 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
     SPTape SNTBK Queue anchors
     Notes : This queue is serialized by *NSS SDF queue lock NSUSDFLK.
0090  144 Dbl-Word     8 NSUSPTAN (0)   Anchors to queue of SPTape SNTBKs
0090  144 Address      4 NSUSPTFW       Foward pointer of SPTape SNTBKs
0094  148 Address      4 NSUSPTBK       Backward pointer of SPTape SNTBKs
     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, the SAVESYS SNTBK queue and the SPTape 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, the SAVESYS SNTBK queue, and the
     SPTape 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 |         NSUSPTFW          |         NSUSPTBK          |
*     +---------------------------+---------------------------+
*  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
NSUSPTAN       0090
NSUSPTBK       0094
NSUSPTFW       0090
NSUSSGAN       0080
NSUSSGBK       0084
NSUSSGFW       0080
NSUSSYAN       0088
NSUSSYBK       008C
NSUSSYFW       0088
NSUSYMAN       00E8
NSUSYQLK       0020

This information is based on z/VM V4R1.0.
Last updated on 6 Jun 2001 at 11:56:18 EDT.
Copyright IBM Corporation, 1990, 2001