HRLBK Back to Index page
Control Block Contents 
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.

  HRLBK Prolog Top of page
 DESCRIPTION: Human Readable Label Table Block
              Each doubleword entry in this control block contains
              an address field and an length field.  These are the
              addresses and lengths of sections of the Human
              Readable Label Table (the 'HR table).  The maximum
              size of the HR table is greater than the maximum
              size of contiguous virtual free storage that can be
              obtained, so the HR table is separated into 'segments'
              which are stored in discontiguous pieces of virtual
              free storage.  The beginning (or all if it's small enough)
              of the table is in the storage pointed to by the first
              word of HRLSEG1 and it continues on through as many
              segments as are required to hold the complete table
              (maximum of five segments).  If an address field of
              an entry is zero, then the complete table has been
              stored in the previous segments.  The length field
              of each doubleword entry contains the length in bytes
              of the segment located by the address field in the
              same entry.
 NOTES      : Virtual free storage is accessible only in
              Access register mode.
        The HR table associates human readable descriptions
        with SECLABELS (Security labels).  Each entry in the
        table has the following format:
        | SECLABEL | LENGTH |  Text describing the SECLABEL    |
         (8 bytes)  (1 byte)   (Variable - length in bytes is
                                           given by the LENGTH
                                           field and is a maximum
                                           of 132 characters.
        The last eight bytes of the table contain x'FF''s
        (i.e. the last eight bytes in the last (nonzero)
        segment are 'FFFFFFFFFFFFFFFF.')
        There is not a control block to map out the entries of
        the table.
 SERIALIZED : Use of the SYSSECTB in SYSCM is serialized.  SYSSECTB contains
              the address of the HRLBK for the current Human Readable Label
              Table.  While reading the HR table, SYSHRTLK should be held
              shared mode (it should be obtained before getting the address
              from SYSSECTB).   While updating the SYSSECTB field, SYSHRTLK
              should be held exclusive mode.
 NOTES      : This control block is bilingual.  The fields within it can
              be referenced in either ASSEMBLER or PLAS modules.
  HRLBK Control Block Content Top of page

 HRLBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure HRLBK Human Readable Label Table Block 0000 0 Dbl-Word 8 HRLSEG1 First word contains the address in virtual free storage of segment 1. The second word contains the length in bytes of the data in segment 1. 0008 8 Dbl-Word 8 HRLSEG2 Address and length of segment 2 0010 16 Dbl-Word 8 HRLSEG3 Address and length of segment 3 0018 24 Dbl-Word 8 HRLSEG4 Address and length of segment 4 0020 32 Dbl-Word 8 HRLSEG5 Address and length of segment 5 00000005 HRLSIZE (*-HRLBK+7)/8
  HRLBK Storage Layout Top of page
*** HRLBK - Human Readable Label Table Block
*     +-------------------------------------------------------+
*   0 |                       HRLSEG1                         |
*     +-------------------------------------------------------+
*   8 |                       HRLSEG2                         |
*     +-------------------------------------------------------+
*  10 |                       HRLSEG3                         |
*     +-------------------------------------------------------+
*  18 |                       HRLSEG4                         |
*     +-------------------------------------------------------+
*  20 |                       HRLSEG5                         |
*     +-------------------------------------------------------+
*  28
*** HRLBK - Human Readable Label Table Block
  HRLBK Cross Reference Top of page
Symbol         Dspl Value
-------------- ---- -----
HRLSEG1        0000
HRLSEG2        0008
HRLSEG3        0010
HRLSEG4        0018
HRLSEG5        0020
HRLSIZE        0020 00000005
This information is based on z/VM 6.3.0 Last updated on 22 May 2013 at 13:54:36 EDT.
Copyright IBM Corporation, 1990, 2013