BLKIO Back to Index page
 
Prolog 
Control Block Contents 
   BLKIO 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.


  BLKIO Prolog Top of page
 
 NAME       : HCPBLKIO
 DESCRIPTION: *BLOCKIO Device Connection Data
 DSECT      : BLKIO
 FUNCTION   : This DSECT maps data representing a successful
              connection to a device by a virtual machine
              using the *BLOCKIO system service
 LOCATED BY : VMDBLKIO field in VMDBK
              VDEVBIOA field in VDEV
 CREATED BY : HCPBIO
 DELETED BY : HCPBIO
 SERIALIZED : Unique task execution
              VMDBK dispatch lock.
 RELOCATION CONSIDERATIONS : None
 
 
  BLKIO Control Block Content Top of page
 

 BLKIO DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure BLKIO *BLOCKIO Device Connection Data 0000 0 Signed 4 BLKNEXT Address of next BLKIO Block 0004 4 Bitstring 1 BLKRC SEVER return code 0005 5 Bitstring 1 BLKSTAT BLKIO status 1... .... BLKSVRD X'80' BLKSVRD SEVER is Pending .1.. .... BLKRESET X'40' BLKRESET RESET is Pending 0006 6 Bitstring 2 BLKPATH IUCV path for this device 0008 8 Signed 4 BLKOFFCP CP offset for minidisk. Must be treated as a signed value. (May be negative.) BLKDBCCT is used to indicate the number of outstanding processes in HCPDBC. It is used to indicate that i/o may be in progress for a particular request. Thus BLKDBCCT and BLKDBIAD both must be 0 for there to be no outstanding *BLOCKIO for this device. 000C 12 Signed 4 BLKDBCCT Count of processes in HCPDBC 0010 16 Signed 4 BLKDBIAD Chain of outstanding DBIRQs 0014 20 Signed 4 BLKDBCWK Chain of outstanding sends to *BLOCKIO 0018 24 Bitstring 16 BLKCPARM (0) User connect parameter list 0018 24 Signed 4 BLKSIZE Block size of user's disk 001C 28 Signed 4 BLKOFFST User's requested offset 0020 32 Signed 2 BLKVDEV Virtual device address 0022 34 Bitstring 6 * Reserved for future IBM use 0028 40 Bitstring 16 BLKPARMA (0) ACCEPT parameter list 0028 40 Signed 4 BLKSTART User's starting block 002C 44 Signed 4 BLKEND User's ending block 0030 48 Bitstring 1 * Reserved for Future IBM Use 0031 49 Bitstring 1 BLKFLAGS Device status flags .... ...1 BLKDEVRD X'01' BLKDEVRD Virtual device is read only 0032 50 Bitstring 2 * Reserved for Future IBM Use 0034 52 Signed 4 BLKSPIRA Special IRA for SEVER processing 0038 56 Signed 4 BLKVDEVA Virtual device block address 003C 60 Signed 4 BLKDINFO Address of device information 0040 64 Signed 4 BLKSAVBK Caller's save block 0048 72 Dbl-Word 8 * (0) Ensure Double Word Boundary 0048 72 Dbl-Word 8 BLKLOWN (3) BLKIO lock 0060 96 Dbl-Word 8 * (0) Ensure Double Word Boundary 0060 96 Bitstring 40 BLKPARML IUCV parameter list 00000011 BLKDSIZE (*-BLKIO+7)/8 Size, in doublewords, of BLKIO
 
 
  BLKIO Storage Layout Top of page
 
 
*** BLKIO - *BLOCKIO Device Connection Data
*
*     +---------------------------+------+------+-------------+
*   0 |         BLKNEXT           |BLKRC |:STAT |  BLKPATH    |
*     +---------------------------+------+------+-------------+
*   8 |         BLKOFFCP          |         BLKDBCCT          |
*     +---------------------------+---------------------------+
*  10 |         BLKDBIAD          |         BLKDBCWK          |
*     +---------------------------+---------------------------+
*  18 |         BLKSIZE           |         BLKOFFST          |
*     +-------------+-------------+---------------------------+
*  20 |  BLKVDEV    |/////////////////////////////////////////|
*     +-------------+-------------+---------------------------+
*  28 |         BLKSTART          |          BLKEND           |
*     +------+------+-------------+---------------------------+
*  30 |//////|:FLAGS|/////////////|         BLKSPIRA          |
*     +------+------+-------------+---------------------------+
*  38 |         BLKVDEVA          |         BLKDINFO          |
*     +---------------------------+---------------------------+
*  40 |         BLKSAVBK          |///////////////////////////|
*     +---------------------------+---------------------------+
*  48 |                                                       |
*     =                       BLKLOWN                         =
*     |                                                       |
*     +-------------------------------------------------------+
*  60 |                                                       |
*     =                       BLKPARML                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  88
*
*** BLKIO - *BLOCKIO Device Connection Data
 
 
  BLKIO Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
BLKCPARM       0018
BLKDBCCT       000C
BLKDBCWK       0014
BLKDBIAD       0010
BLKDEVRD       0031 01
BLKDINFO       003C
BLKDSIZE       0060 00000011
BLKEND         002C
BLKFLAGS       0031
BLKLOWN        0048
BLKNEXT        0000
BLKOFFCP       0008
BLKOFFST       001C
BLKPARMA       0028
BLKPARML       0060
BLKPATH        0006
BLKRC          0004
BLKRESET       0005 40
BLKSAVBK       0040
BLKSIZE        0018
BLKSPIRA       0034
BLKSTART       0028
BLKSTAT        0005
BLKSVRD        0005 80
BLKVDEV        0020
BLKVDEVA       0038
 
This information is based on z/VM 6.4.0 Last updated on 24 Aug 2016 at 09:22:58 EDT.
Copyright IBM Corporation, 1990, 2016