DASD

Add_Parms

Delete_Parms

Query_Parms

Options

Notes:

¹ For more information on prefix keywords, see the DIRMAINT EXEC.
² Neither (LINEAR) nor (ROTATING) is permitted for an existing group. (LINEAR) is the default for a new group.

Purpose

Use the DASD operand of the DIRMAINT command to synchronously update the DASD management EXTENT CONTROL file.

Operands

group_name

Specifies the name of this group entry. Specification of this field is subject to the following rules:

If a group entry shares the same name with another group entry, it is considered a single group. For instance, consider the following groups segment from an EXTENT CONTROL file:
```
MyGroup   Mike1 Mike2
MyGroup2  Mark1
MyGroup   Mike3
```
This series of statements actually defines two groups, MyGroup and MyGroup2. The same information could have been represented as:
```
MyGroup   Mike1 Mike2 Mike3
MyGroup2  Mark1
```
This gives the user the ability to define large groups without using excessively long records.
Group names must not start with a valid EXTENT CONTROL file tag.
Group names may consist of characters from the following list: A-Z, 0-9, #, @, $, :, - and +.
DirMaint requires that this field be eight characters or less.

(LINEAR)

Specifies the linear scanning method, in which the first region within a group is scanned for allocation until full, then the second region, and so on, up until the last region.

(ROTATING)

Specifies the rotating scanning method, in which the first region within a group is scanned for the first allocation, then the second region for the second allocation, and so on, with each new allocation starting at the next region.

region_name

Specifies the name of this region entry. Specification of this field is subject to the following rules:

Region names must be unique. If a region entry shares the same name with another region entry, the first record is used, the second entry is ignored.
Region names may consist of characters from the following list: A-Z, 0-9, #, @, $, :, - and +. DirMaint requires that this field be eight characters or less.

volid

Specifies the volume ID of the region where the region is located.

This value represents the value placed into the volid field on any minidisks generated from this region.
Volume IDs supported by DirMaint consist of characters from the following list: A-Z, 0-9, #, @, $, :, - and +.

devtype

Specifies the DASD type associated with each entry.

size

Specifies the block size of this entry. A keyword of END can be used to specify the end (last cylinder) of the volume.

Note that if the VOLUME is not defined to the system, you need to supply both the size and start values. When adding a VOLUME, the size value must be greater than the start value.

The regend value is calculated and updated in the EXTENT CONTROL file as:

regend = (start + size) -1

The volend value is calculated and updated in the EXTENT CONTROL file as:

volend = size -1

start

Specifies the starting block or cylinder (inclusive) of the region. A keyword of START can be used to define the start of a region. This translates to cylinder 1 of a CKD device and block 32 of an FBA device.

Note that if the VOLUME is not defined to the system, you need to supply both the size and start values. When adding a VOLUME, the size value must be greater than the start value.

comments

Additional comments that will be included in the reports. (See Reports.)

USEDext

Specifies that a listing should be generated showing allocated extents on volumes, groups, and regions used to contain minidisks. For more information on USEDext, see USEDEXT.

FREExt

Specifies that a listing should be generated showing free extents on volumes, groups, and regions used to contain minidisks. For more information on FREExt, see FREEXT.

Reports

The reports returned by the QUERY, USEDext, and FREExt options will appear in the following formats:

QUERY GROUP

DVHDSD3561I GROUP=group_name ALLOCATE={LINEAR|ROTATING} REGIONS=nn
DVHDSD3562I GROUP=group_name REGIONS= reg1 reg2 reg3 ... regnn

Unless the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the response will be returned in the message format shown above. There will be one 3561 message per group, and as many 3562 messages as needed to list all of the regions in the group.

If the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the result will be a reader file containing the above format without the message number ('DVHDSD3561I' and 'DVHDSD3562I') prefixes. The name of the file returned is dependent on the options specified on the command, as follows:

group_name QUERY: will be returned if one specific group name was specified on the command.
ALLGRPS QUERY: will be returned if the command was issued with a group name of '*'.
MULTIGRP QUERY: will be returned if the command was issued with more than one group name.

QUERY REGION

DVHDSD3563I REGION   VOLUME    START      SIZE        END    DEV-TYPE COMMENTS
DVHDSD3564I xxxxxxxx volidx nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn dddddddd etc.
DVHDSD3564I xxxxxxxx volidx nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn dddddddd etc.

Unless the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the response will be returned in the message format shown above. There will be one 3563 message per query request, and one 3564 message per each region. The SIZE column is calculated as (END-START)+1.

If the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the result will be a reader file containing the above format without the message number ('DVHDSD3563I' and 'DVHDSD3564I') prefixes. The name of the file returned is dependent on the options specified on the command, as follows:

region_name QUERY: will be returned if one specific region name was specified on the command.
ALLREGS QUERY: will be returned if the command was issued with a region name of '*'.
MULTIREG QUERY: will be returned if the command was issued with more than one region name.

QUERY VOLUME

DVHDSD3565I VOLUME DEV-TYPE    SIZE        END
DVHDSD3566I xxxxxx dddddddd nnnnnnnnnn nnnnnnnnnn
DVHDSD3566I xxxxxx dddddddd nnnnnnnnnn nnnnnnnnnn

Unless the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the response will be returned in the message format shown above. There will be one 3565 message per query request, and one 3566 message per each volume. The END column is calculated as SIZE-1.

If the RETVIA/RETURNVIA RDRFILE prefix keyword is used, the result will be a reader file containing the above format without the message number ('DVHDSD3565I' and 'DVHDSD3566I') prefixes. The name of the file returned is dependent on the options specified on the command, as follows:

volume_name QUERY: will be returned if one specific volume name was specified on the command.
ALLVOLS QUERY: will be returned if the command was issued with a volume name of '*'.
MULTIVOL QUERY: will be returned if the command was issued with more than one volume name.

USEDext

USEDEXT operands   

  GROUP   REGION  VOLUME    START      SIZE       (END)     OWNER  ADDR    SA    NOTES   
-------- -------- ------ ---------- ---------- ---------- -------- ---- -------- -----   
gggggggg rrrrrrrr vvvvvv nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn uuuuuuuu aaaa ssssssss notes
gggggggg rrrrrrrr vvvvvv nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn uuuuuuuu aaaa ssssssss notes

Unless the RETVIA/RETURNVIA prefix keyword is used, the result will be a reader file in the above format. There will be one header line per request. There will usually be one detail line per minidisk entry. The "GROUP" column will show an "*" for a REGION or VOLUME report. The "REGION" column will show an "*" for a VOLUME report. The (END) column is calculated as (START+SIZE)-1. If the minidisk is contained within multiple overlapping regions, or in a region that is included in more than one group, there may be multiple entries for that minidisk record.

FREExt

FREEXT operands
 
  GROUP   REGION  VOLUME    START      SIZE       (END)     OWNER  ADDR    SA   
-------- -------- ------ ---------- ---------- ---------- -------- ---- --------
gggggggg rrrrrrrr vvvvvv nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn .FREE.   0000 *
gggggggg rrrrrrrr vvvvvv nnnnnnnnnn nnnnnnnnnn nnnnnnnnnn .FREE.   0000 *

Unless the RETVIA/RETURNVIA prefix keyword is used, the result will be a reader file in the above format. There will be one header line per query request. There will usually be one detail line per free space entry. The "GROUP" column will be an "*" for a REGION or VOLUME report. The "REGION" column will be an "*" for a VOLUME report. The (END) column is calculated as (START+SIZE)-1.

Note that output is similar to the USEDext report, except for the following:

OWNER will be ".FREE."
ADDR will be "0000"
SYSAFFIN will be "*"

If the free space is contained within multiple overlapping regions, or in a region that is included in more than one group, there may be multiple entries for that free space record.

Usage Notes

You may use one or more of the prefix keywords (REQuest, TOsys, ASuser, BYuser, PRESET, RETurnvia/RETVia) with this command. These prefix keywords may be specified in any order, but each keyword may only be specified once. The FOR and AT prefix keywords are not applicable to the command. They are accepted without error, but otherwise ignored.
When adding a VOLUME, the size value must be greater than the start value.
The DASD ADD GROUP group_name command updates the :GROUPS. section in the EXTENT CONTROL file. The format is:
```
group_name region_name1 region_name2 ... region_namen
```
The DASD ADD REGION region_name command updates the :REGIONS. section in the EXTENT CONTROL file. The format is:
```
regionid volser regstart regend ttttmmmm
```
where regend is calculated using the size and start values as follows:
```
regend = (start + size) - 1
```
The DASD ADD VOLUME volid command updates the :REGIONS. section in the EXTENT CONTROL file. The format is:
```
volser volser volstart volend ttttmmmm
```
where volend is calculated using the size value as follows:
```
volend = size - 1
```
The Special User IDs in the Default User Directory (USER DIRECT) section in z/VM: Installation Guide recommends using and/or updating special dummy user IDs in the default user directory (USER DIRECT) to track allocation of CP areas on a volume. For example, the $DIRECT$ user ID tracks directory cylinders/blocks. The CP QUERY ALLOC MAP command identifies CP reserved areas, and these areas are tracked by DirMaint in the command output as .DRCT., .PAGE., .SPOOL., and .TDISK. areas. The DASD USEDEXT and DASD FREEXT commands do not list overlaps between a special user ID and the allocation extents information when the extents exactly match. This avoids an OVERLAP warning on those extents.