NAME       : HCPALOC
 DESCRIPTION: DASD VOLUME ALLOCATION BLOCK
 DSECT      : ALOC
 FUNCTION   : Maps the DASD allocation record on DASD for
              CYLINDER-BASED ALLOCATION MAPPING.
              (ECKD/CKD DASD with less than or equal to
              ALOCMAXCM cylinders.)
 LOCATED BY : The allocation record resides on CP formatted CKD
              and ECKD DASD on cylinder 0, head 0, record 4.  It
              exists only temporarily in storage.
 CREATED BY : ICKDSF when a CKD or ECKD DASD
              with less than or equal to ALOCMAXCM cylinders
              is formatted for CP use.
 DELETED BY : Exists in storage only until the in-storage
              representation of the allocation map (HCPVEXBK,
              HCPEXTBK) is built.
 RELOCATION CONSIDERATIONS : None
 COMMENTS   :
              If a CKD or ECKD DASD with more than ALOCMAXCM cylinders
              is formatted by ICKDSF, then an EXTENT-BASED ALLOCATION
              MAPPING is used.
              ALOC DSECT maps all CYLINDER-BASED ALLOCATION MAPPING.
              ALOCEXT DSECT maps all EXTENT-BASED ALLOCATION MAPPING.

 ALOC DSECT
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Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      ALOC           DASD VOLUME ALLOCATION BLOCK
0000    0 Bitstring    1 ALOCNTS        VOLUME TYPE CONTENTS THIS BYTE
                                        CONTAINS THE RESULTING BIT
                                        CONFIGURATION OBTAINED BY ORING
                                        ALL USE FLAGS THAT REPRESENT TYPE
                                        OF CYLINDERS ALLOCATED ON THIS
                                        VOLUME.
          1... ....      ALOCATED       X'80' ALOCATED CYLINDER IS
                                        CURRENTLY IN USE THIS TYPE OF
                                        ALLOCATION SHOULD ONLY BE USED IN
                                        CONJUNCTION WITH THE TYPE 'DRCT'
          .1.. ....      ALOCDRCT       X'40' ALOCDRCT ALLOCATION TYPE
                                        'DRCT'
          ..1. ....      ALOCTDSK       X'20' ALOCTDSK ALLOCATION TYPE
                                        'TDSK'
          ...1 ....      ALOCFULL       X'10' ALOCFULL CYLINDER IS FULL
                                        NOTE- ALOCFULL is used only in
                                        combination with SPOL & PAGE
          .... 1...      ALOCPERM       X'08' ALOCPERM ALLOCATION TYPE
                                        'PERM'
          .... ..1.      ALOCSPOL       X'02' ALOCSPOL ALLOCATION TYPE
                                        'SPOL' Notes : ALOCSPOL ==
                                        PGTSPOOL == PGUSPOOL == CPVTEMPS:
0001    1 Bitstring    1 ALOAVAIL       AVAILABILITY OF TYPES
          1... ....      ALOCATED       X'80' ALOCATED CYLINDER IS
                                        CURRENTLY IN USE THIS TYPE OF
                                        ALLOCATION SHOULD ONLY BE USED IN
                                        CONJUNCTION WITH THE TYPE 'DRCT'
          .1.. ....      ALOCDRCT       X'40' ALOCDRCT ALLOCATION TYPE
                                        'DRCT'
          ..1. ....      ALOCTDSK       X'20' ALOCTDSK ALLOCATION TYPE
                                        'TDSK'
          ...1 ....      ALOCFULL       X'10' ALOCFULL CYLINDER IS FULL
                                        NOTE- ALOCFULL is used only in
                                        combination with SPOL & PAGE
          .... 1...      ALOCPERM       X'08' ALOCPERM ALLOCATION TYPE
                                        'PERM'
          .... ..1.      ALOCSPOL       X'02' ALOCSPOL ALLOCATION TYPE
                                        'SPOL' Notes : ALOCSPOL ==
                                        PGTSPOOL == PGUSPOOL == CPVTEMPS:
0002    2 Signed       2 ALOCYLS        NUMBER OF CYLINDERS ON DEVICE
                                        Note that the high order bit in
                                        ALOCYLS (3rd byte of the
                                        allocation map) is reserved. It
                                        indicates whether or not the map
                                        is an extent-based map. In this
                                        cylinder-based form of the
                                        allocation map, the bit is off.
0004    4 Signed       4 * (2)          Reserved for IBM use
000C   12 Bitstring    1 ALOSTAT        VOLUME STATUS FLAG
          .1.. ....      ALOCNFIL       X'40' ALOCNFIL ALL 'CP SPACE' ON
                                        THIS VOLUME IS FORMATTED WITHOUT
                                        FILLER RECORDS
000D   13 Bitstring    1 ALOCODE        Index into CPVOL list
000E   14 Signed       2 *              RESERVED FOR FUTURE IBM USE
0010   16 Bitstring    8 ALOCMAP (0)    START OF VARIABLE LENGTH DATA
          1... ....      ALOCATED       X'80' ALOCATED CYLINDER IS
                                        CURRENTLY IN USE THIS TYPE OF
                                        ALLOCATION SHOULD ONLY BE USED IN
                                        CONJUNCTION WITH THE TYPE 'DRCT'
          .1.. ....      ALOCDRCT       X'40' ALOCDRCT ALLOCATION TYPE
                                        'DRCT'
          ..1. ....      ALOCTDSK       X'20' ALOCTDSK ALLOCATION TYPE
                                        'TDSK'
          ...1 ....      ALOCFULL       X'10' ALOCFULL CYLINDER IS FULL
                                        NOTE- ALOCFULL is used only in
                                        combination with SPOL & PAGE
          .... 1...      ALOCPERM       X'08' ALOCPERM ALLOCATION TYPE
                                        'PERM'
          .... ..1.      ALOCSPOL       X'02' ALOCSPOL ALLOCATION TYPE
                                        'SPOL' Notes : ALOCSPOL ==
                                        PGTSPOOL == PGUSPOOL == CPVTEMPS:
          .... ...1      ALOCPAGE       X'01' ALLOCATION TYPE 'PAGE'
                                        Notes : ALOCPAGE == PGTPAGE ==
                                        PGUPAGE == CPVTEMPP:
          .... 11..      ALOCMDSK       X'0C' Allocation type 'MDSK'
          ...1 11..      ALOCMORE       X'1C' Allocation type 'MORE'
          1... ....      ALOCDRAN       X'80' Device is permanently
                                        drained.
          .... ....      ALOCUNDF       X'00' Undefined allocation type;
                                        these cylinders/pages are ignored
0010   16 Bitstring    1 ALOCBYTE       Allocation byte for a single
                                        cylinder
0011   17 Bitstring    1 ALOCNEXT       Position of next allocation byte

          
*** ALOC - DASD VOLUME ALLOCATION BLOCK
*
*     +------+------+-------------+---------------------------+
*   0 |:CNTS |:AVAIL|  ALOCYLS    |///////////////////////////|
*     +------+------+-------------+------+------+-------------+
*   8 |///////////////////////////|:STAT |:CODE |/////////////|
*     +---------------------------+------+------+-------------+
*
*** ALOC - DASD VOLUME ALLOCATION BLOCK
          
*** Overlay for ALOCMAP in ALOC
*
*     +------+------+
*  10 |:CBYTE|:CNEXT| 12
*     +------+------+
*
*** Overlay for ALOCMAP in ALOC

 
Symbol         Dspl Value
-------------- ---- -----
ALOAVAIL       0001
ALOCATED       0000 80
ALOCATED       0001 80
ALOCATED       0010 80
ALOCBYTE       0010
ALOCDRAN       0010 80
ALOCDRCT       0000 40
ALOCDRCT       0001 40
ALOCDRCT       0010 40
ALOCFULL       0000 10
ALOCFULL       0001 10
ALOCFULL       0010 10
ALOCMAP        0010
ALOCMDSK       0010 0C
ALOCMORE       0010 1C
ALOCNEXT       0011
ALOCNFIL       000C 40
ALOCNTS        0000
ALOCODE        000D
ALOCPAGE       0010 01
ALOCPERM       0000 08
ALOCPERM       0001 08
ALOCPERM       0010 08
ALOCSPOL       0000 02
ALOCSPOL       0001 02
ALOCSPOL       0010 02
ALOCTDSK       0000 20
ALOCTDSK       0001 20
ALOCTDSK       0010 20
ALOCUNDF       0010 00
ALOCYLS        0002
ALOSTAT        000C