z/OS DFSMSdfp Advanced Services
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Data Facilities Area (DFA) Fields

z/OS DFSMSdfp Advanced Services
SC23-6861-01

Except for DFADFVAD, all of the fields in the DFA are part of the intended programming interface.

Common Name:
Data Facilities Area
Macro ID:
IHADFA
DSECT Name:
DFA
Eye-Catcher ID:
DFAACRON
Subpool and Key:
Nucleus resident and Key 0; Resident below 16MB
Size:
112 bytes
Created by:
Assembled into nucleus
Pointed to by:
CVTDFA field of the CVT
Serialization:
N/A
Function:
Maps the Data Facilities Area, which contains information that applies to DFSMS.
Table 1. DFA Fields
Offset   Type/Value Length Name Description
0(0)   UNSIGNED 2 DFALEN LENGTH OF THIS TABLE  
VERSION, RELEASE, AND MODIFICATION LEVEL INFORMATION FOR DFP. THE FIRST THREE DIGITS OF DFAREL REPRESENTS THE LAST LEVEL OF DFP(X'332'). THE FOURTH DIGIT OF DFAREL BEING NON-ZERO INDICATES THE LEVEL OF THIS PRODUCT IS HIGHER THAN THE INDICATED LEVEL.
2(2)   BITSTRING 2 DFAREL FOUR DIGITS = VERSION, RELEASE, MOD, X  
THE FOLLOWING ARE THE FEATURE BYTES. WHEN A BIT IS ON, IT MEANS EITHER THAT THE CURRENT RELEASE SUPPORTS THE FEATURE OR THAT THIS PARTICULAR INSTANCE OF THE SYSTEM SUPPORTS THE FEATURE. IF THE SOFTWARE SUPPORTS A FEATURE BUT IT CANNOT BE USED, PERHAPS BECAUSE COREQUISITE SOFTWARE OR HARDWARE IS NOT AVAILABLE, THEN THE FEATURE BIT WILL BE OFF.
4(4)   SIGNED 4 DFAFEATS(0) ALL FEATURES BYTES–USED BY CS INSTR
4(4)   BITSTRING 1 DFAFEAT1 FEATURES BYTE 1
    1... ....   DFAXA "X'80'" MVS/XA (COPY OF CVTMVSE IN CVT)
    .1.. ....   DFALSR "X'40'" MULTIPLE VSAM LSR POOLS SUPPORTED (1.1.0)
    ..1. ....   DFAEOS "X'20'" DASDM ERASE ON SCRATCH SUPPORTED (2.1.0)
    ...1 ....   DFAXRF "X'10'" EXTENDED RECOVERY FACILITY (2.1.0)
    .... 1...   DFAEXPCI "X'08'" EXPORT BY CONTROL INTERVAL (2.1.0)
    .... .1..   DFAEOSIC "X'04'" ERASE ON SCRATCH FOR ICF (2.1.0)
    .... ..1.   DFASMS "X'02'" SYSTEM MANAGED STORAGE (3.1.0)
    .... ...1   DFAPDSE "X'01'" PDSE SUPPORT AVAILABLE ON THE SYSTEM SET BY IEAVNP26 WHEN DFP LEVEL IS 3.2.0 OR GREATER AND AN APPROPRIATE LEVEL OF SP EXISTS.
    .... ...1   DFAIPDS "DFAPDSE" IPDS IS OLD NAME FOR PDSE
5(5)   BITSTRING 1 DFAFEAT2 FEATURES BYTE 2
    1... ....   DFADLS "X'80'" RESERVED
    .1.. ....   DFAPML "X'40'" RESERVED
    ..1. ....   DFAFMS "X'20'" FILE MANAGEMENT SERVICES SUPPORTED
    ...1 ....   DFACMPAC "X'10'" INSTALLATION DEFAULT FOR COMPACTION
    .... 1...   DFABPBLD "X'08'" BYPASS CHANNEL PROGRAM PREFIX BUILD
    .... .1..   DFASSF "X'04'" SSF SERVICES ARE AVAILABLE
    .... ..1.   DFAMMEXT "X'02'" MMS SUPPORTS XTIOT
    .... ...1   DFAINDEF "X'01'" COMPACTION DEFAULT EXPLICITLY SET BY INSTALLATION
6(6)   BITSTRING 1 DFAFEAT3 FEATURES BYTE 3
    1... ....   DFAVOLSN "X'80'" VOLSER EXTRACTED FROM SENSE INFO ACCEPTABLE BY THE INSTALLATION
    .1.. ....   DFASAMEX EXTENDED FORMAT SEQUENTIAL DATA SETS SUPPORTED
    .1.. ....   DFASMSEX ALIAS FOR DFASAMEX
    ..1. ....   DFAKSDEX EXTENDED FORMAT KSDS SUPPORTED
    ...1 ....   DFACMPCT DFSMS ACCESS METHOD COMPRESSION SUPPORTED. BIT SET BY SMS SUB-SYSTEM INITIALIZATION.
    .... 1...   DFARLSJ3 THE SMSVSAM SERVER HAS SUCCESSFULLY INITIALIZED ON THIS SYSTEM. THIS BIT IS USED BY SMS SCHEDULING. ONCE ON, THIS BIT REMAINS ON FOR THE LIFE OF THE IPL. THIS BIT DOES NOT INDICATE THAT THE SMSVSAM SERVER IS CURRENTLY OPERATIONAL.
    .... .1..   DFARECAL DATA SET RECALL CAPABILITY VIA® THE ARCHRCAL MACRO IS AVAILABLE.
    .... ..1.   DFADEEXT DESERV EXIT FUNCTION IS AVAILABLE
    .... ...1   DFADLL DFSMS DLL SUPPORT IS AVAILABLE
7(7)   BITSTRING 1 DFAFEAT4 FEATURES BYTE 4
    1... ....   DFAFDAT RESERVED
    .1.. ....   DFANSRV DFP NIP SERVICES CAN BE INVOKED VIA IGGSSRV MACRO
    ..1. ....   DFADYNL DYNAMIC LINKLIST IS SUPPORTED
    ..1. ....   DFACIR2 THE CATALOG INFORMATION ROUTINE, IKJEHCIR, SUPPORTS A FORMAT 2 WORK AREA, I.E., FULL WORD LENGTH FIELDS
    .... 1...   DFADYLPA DFSMS SUPPORT FOR DYNAMIC LPA IS AVAILABLE.
    .... .1..   DFAFORK DFSMS LOADER FORK EXIT IS PRESENT
    .... ..1.   DFASNBK SOFTWARE SUPPORT PROVIDING “FAST” BACKUP USING THE SNAPSHOT FEATURE OF THE RAMAC VIRTUAL ARRAY (RVA) INSTALLED.
    .... ...1   DFASNAP THE API SUPPORT FOR THE SNAPSHOT FEATURE OF THE RAMAC VIRTUAL ARAY (RVA) IS INSTALLED.
8(8)   CHARACTER 4 DFAACRON ACRONYM FOR THIS CONTROL BLOCK.
12(C)   BITSTRING 1 DFAFEAT5 FEATURES BYTE 5
    1... ....   DFAUPDSE UNMANAGED PDSE SUPPORT INSTALLED ON THIS SYSTEM.
    .1.. ....   DFABTSREQ 1 means BLOCKTOKENSIZE=REQUIRE in IGDSMSxx member of PARMLIB. Restrictions on opening large format data sets. 0 means BLOCKTOKENSIZE=NOREQUIRE.
    ..1. ....   DFABLDLS BLDL START= and STOP= parameters are supported.
    ...1 ....   DFAUSEAV System default USEEAV setting for an extended address volume (EAV) when SMS is not active. Initially set on, to allow the use of EAV, and changed to the IGDSMSxx PARMLIB specified or defaulted USEEAV value if SMS is active.
    ....1...   DFASAMHPF SAM_USE_HPF, On = yes

Note: If DFASAMHPF is set but ZHPF=YES in IECIOSxx is not in effect, BAM will not use zHPF.
    .... .x..     RESERVED.
    .... ..1.   DFAALVER VERSION LEVEL AT WHICH NEW TAPE LABELS WILL BE WRITTEN. OFF: ANSI LABEL VERSION 3. ON: ANSI LABEL VERSION 4.
    .... ...1   DFAALFOR DETERMINES WHETHER INSTALLATION ISO/ANSI VERSION LEVEL IS FORCED
13(D)   BITSTRING 1 DFAFEAT6 FEATURES BYTE 6
    1111 ....   DFACPSDB COPYSDB VALUE IN DEVSUPxx IN PARMLIB. SYSTEM LEVEL DEFAULT FOR THE SDB OPTION OF IEBGENER AND OTHER COPYING PROGRAMS. VAE CONSTANTS BELOW DFACPS**
    0001 ....   DFACPSNO COPYSDB = NO
    0010 ....   DFACPSYE COPYSDB = YES
    0010 ....   DFACPSSM COPYSDB = SMALL (SAME AS COPYSDB = YES)
    0011 ....   DFACPSIN COPYSDB = INPUT
    0100 ....   DFACPSLA COPYSDB = LARGE
    .... 1...   DFADCMET Data class media enforced for all tapes outside of libraries (ENFORCE_DC_MEDIA=ALMEDIATY)
    .... .1..   DFADCMEJ Data class media enforced for IBM® 3592 outside of libraries (ENFORCE_DC_MEDIA=MEDIA5PLUS)
    .... ..1.   DFAMTLAM When no media preference is expressed, accept all media types for a manual tape library (MTL_NO_DC_WORM_OK)
    .... ...1   DFASTIFF STOW supports the IFF operand
14(E)   UNSIGNED 2 DFABPV System default break point value (BPV) for an extended address volume (EAV) when the BPV is not specified in the SMS IGDSMSxx PARMLIB or when SMS is not active. Initially set to 10 and changed to the IGDSMSxx SPECIFIED BPV value if SMS is active.
PRODUCT, VERSION, RELEASE, AND MODIFICATION LEVEL INFORMATION. BYTE 0 DEFINES A PRODUCT CODE, BYTES 1-3 DEFINE THE VERSION, RELEASE, AND MODIFICATION LEVELS OF THIS PRODUCT. A PRODUCT BYTE (DFAPROD) OF X'00' INDICATES DFP AS A PRODUCT, BYTES 1-3 OF DFARELS WILL ALSO BE X'00' IN THIS CASE. THE USER MAY CHOOSE TO CHECK DFAREL FOR THE RELEASE LEVEL OF THE DFP PRODUCT IN THIS CASE. IF DFAPROD IS NOT EQUAL TO X'00', DFAREL SHOULD NOT BE CHECKED AS IT WILL BE FROZEN AT THE LAST LEVEL OF DFP PRODUCT SHIPPED. A PRODUCT BYTE (DFAPROD) OF X'01' INDICATES DFSMS AS A PRODUCT BYTES 1-3 OF DFARELS WILL INDICATE THE VERSION, RELEASE AND MODIFICATION LEVELS OF THE DFSMS PRODUCT. A PRODUCT BYTE (DFAPROD) OF X'02' INDICATES OS/390®. THIS VALUE INDICATES THIS LEVEL OF DFSMS IS OS/390 EXCLUSIVE. SINCE DFSMS MIGHT NOT BE REFRESHED WITH EACH OS/390 RELEASE, THE VERSION, RELEASE, AND MODIFICATION FIELDS INDICATE THE LEVEL OF OS/390 IN WHICH THIS LEVEL OF DFSMS WAS FIRST SHIPPED. THE VERSION, RELEASE, AND MODIFICATION FIELDS ARE BINARY VALUES. (FOR EXAMPLE TEN WOULD BE X'0A').
16(10)   BITSTRING 4 DFARELS 4 BYTES = PRODUCT, VERSION, REL, MOD
16(10)   BITSTRING 1 DFAPROD PRODUCT BYTE
    0000 0000   DFADFP DFP PRODUCT CODE.
    0000 0001   DFADFSMS PRODUCT CODE FOR DFSMS.
    0000 0002   DFAOS390 PRODUCT CODE FOR OS/390 VERSION 2.
    0000 0003   DFAZOS PRODUCT CODE FOR z/OS®.
17(11)   BITSTRING 1 DFAVER VERSION BYTE
18(12)   BITSTRING 1 DFARLSE RELEASE BYTE
19(13)   BITSTRING 1 DFAMOD MODIFICATION BYTE
20(14)   SIGNED 2 DFAMSMDE MAXIMUM LENGTH OF THE SMDE IN THIS RELEASE WITH AN 8-BYTE ALIAS NAME
22(16)   UNSIGNED 1 DFAVERBO FLAGS
    1... ....   * Reserved.
    .1.. ....   DFATVS IF ON, TRANSACTIONAL VSAM IS INSTALLED.
Start of change   End of change Start of change   End of change Start of change ..1. .... End of change Start of change   End of change Start of change DFAFCXHS End of change Start of change FlashCopy® across Hyperswap enabled End of change
Start of change 23(17) End of change Start of change   End of change Start of change UNSIGNED End of change Start of change 1 End of change Start of change DFASEFVR End of change Start of change Data set format version for new sequential extended format data sets. This is set by the PS_EXT_VERSION keyword in the IGDSMSxx member of SYS1.PARMLIB. End of change
24(18)   ADDRESS 4 DFACSSVT CALLABLE SYSTEM SERVICES VECTOR TABLE ADDRESS
28(1C)   ADDRESS 4 DFADCVSO DATA CONVERSION SERVICES –OPEN.
32(20)   ADDRESS 4 DFADCVSD DATA CONVERSION SERVICES –CONVERT.
36(24)   ADDRESS 4 DFADCVSC DATA CONVERSION SERVICES –CLOSE.
40(28)   ADDRESS 4 DFAELNMP Address of DFSMS element name. Name is mapped by DSECT DFAELNM. See Table 2. Valid only on z/OS 1.3 and later.
44(2C)   ADDRESS 4 DFADFVAD DATA FACILITIES VECTOR TABLE ADDR
END OF DFA AS IT WAS WHEN IT WAS FIRST SHIPPED IN MVS/XA DFP VERSION 2 RELEASE 1 MODIFICATION LEVEL 0. PRIOR TO REFERENCING ANY FIELD BEYOND THIS COMMENT, THE USER MUST ENSURE THAT DFARELS IS GREATER THAN OR EQUAL TO X'02020A00' OR DFALEN IS BIG ENOUGH (SEE DFALEN).
48(30)   INTEGER 8 DFABLKSZ LIMIT ON SYSTEM DETERMINED BLOCK SIZE. DEFAULT IS 32760. OBTAINED FROM DEVSUPxx PARMLIB MEMBER.
56(38)   BITSTRING 1 DFAFEAT7 FEATURES BYTE 7 
    1... ....   DFATADSN TAPEAUTHDSN=YES
    .1.. ....   DFATADS1 TAPEAUTHF1=YES
    ..1. ....   DFATARC8 TAPEAUTHRC8=WARN
    ...1 ....   DFATARC4 TAPEAUTHRC4=FAIL
    .... 1...   DFAXTBAM THE NON_VSAM_XTIOT OPTION OF THE DEVSUPxx MEMBER OF PARMLIB HAS BEEN SET TO 'YES'.
    .... .1..   DFATPMVA TAPEMULTIVOLUMEERROR=ALLOW.
    .... ..1.   DFATPMVF TAPEMULTIVOLUMEERROR=FAIL.
Start of change   End of change Start of change   End of change Start of change .... ...1 End of change Start of change   End of change Start of change   End of change Start of change Reserved End of change
57(39)   BITSTRING 1 DFAFEAT8 FEATURES BYTE 8. The following 7 flags indicate VSAM and non-VSAM data set support for the Extended Addressing Space (EAS) on an EAV.
THE FOLLOWING 8 FLAGS INDICATE VSAM AND NON-VSAM DATA SET SUPPORT FOR THE EXTENDED ADDRESSING SPACE (EAS) ON AN EAV
    1... ....   DFAVSAMFOREAS VSAM enabled for EAS
    .1.. ....   DFASEQFOREAS Basic, large format sequential (QSAM, BSAM, BDAM access) enabled for EAS
    ..1. ....   DFAPDSEFOREAS PDSE enabled for EAS
    ...1 ....   DFAPDSFOREAS PDS enabled for EAS
    .... 1...   DFADIRFOREAS Direct (BDAM access) enabled for EAS
    .... .1..   DFAEFSEQFOREAS Extended format sequential enabled for EAS
    .... ..1.   DFAUNDEFFOREAS Undef DSORGs enabled for EAS
Start of change   End of change Start of change   End of change Start of change .... ...1 End of change Start of change   End of change Start of change DFAEXPMSG End of change Start of change EXPIRATION_MESSAGE=NEVER End of change
58(3A)     6    
Start of change 58(3A) End of change Start of change   End of change Start of change Unsigned End of change Start of change 2 End of change Start of change DFADDRSZ End of change Start of change Storage size limit allowed in DDR swap (number of megabytes) End of change
Start of change 58(3A) End of change Start of change   End of change Start of change Unsigned End of change Start of change 2 End of change Start of change DFADDRSZ End of change Start of change Storage size limit allowed in DDR swap (number of megabytes) End of change
Start of change 60 (3C) End of change Start of change   End of change Start of change Bit String End of change Start of change 1 End of change Start of change DFAFEAT9 End of change Start of change FEATURES BYTE 9 End of change
Start of changeEnd of change Start of change   End of change Start of change 1... .... End of change Start of changeEnd of change Start of change DFAJ3AA End of change Start of change JES3_ALLOC_ASSIST ENABLED End of change
Start of changeEnd of change Start of change   End of change Start of change .1.. .... End of change Start of changeEnd of change Start of change DFAMEMUX End of change Start of change MEMBER SELECTION USER EXIT SUPPORT End of change
Start of change   End of change Start of change   End of change Start of change ..1. .... End of change Start of change   End of change Start of change DFAPDSEG End of change Start of change PDSE Generation support is installed End of change
Start of change   End of change Start of change   End of change Start of change ...1 .... End of change Start of change   End of change Start of change DFAZEDCCMP End of change Start of change zEDC Compression support is installed End of change
Start of change 61 (3D) End of change Start of change   End of change Start of changeEnd of change Start of change 3 End of change Start of changeEnd of change Start of change Reserved End of change
Start of change 64 (40) End of change Start of change   End of change Start of change Unsigned End of change Start of change 8 End of change Start of change DFA47S End of change Start of change PRSDx47 counts (Use for QUERYFC) End of change
Start of change 64 (40) End of change Start of change   End of change Start of change Signed End of change Start of change 4 End of change Start of change DFA47MAX End of change Start of change Maximum PRSD47 so far End of change
Start of change 68 (44) End of change Start of change   End of change Start of change Signed End of change Start of change 4 End of change Start of change DFA47CNT End of change Start of change Current PRSDx47s count End of change
Start of change 72 (48) End of change Start of change   End of change Start of change Bit string End of change Start of change 4 End of change Start of change DFAFEATC End of change Start of change HPF/FCX Feature Code bytes End of change
Start of changeEnd of change Start of change   End of change Start of change ..1. .... End of change Start of change 4 End of change Start of changeEnd of change Start of change Multi track operations supported End of change
Start of changeEnd of change Start of change   End of change Start of change .... 1... End of change Start of changeEnd of change Start of change DFAFCX_TTEDcw End of change Start of change Transfer TCA Extension End of change
Start of changeEnd of change Start of change   End of change Start of change .... .1.. End of change Start of changeEnd of change Start of change DFAFCX_REL1 End of change Start of change FCX phase 1 End of change
Start of changeEnd of change Start of change   End of change Start of change .... ..1. End of change Start of changeEnd of change Start of change DFAFCX_ImbeddedLR End of change Start of change Imbedded LR List End of change
Start of changeEnd of change Start of change   End of change Start of change .... ...1 End of change Start of changeEnd of change Start of change DFAFCX_FmtUpdWrt End of change Start of change Format Update Writes End of change
Start of change 73 (49) End of change Start of change   End of change Start of change Bit string End of change Start of change 1 End of change Start of changeEnd of change Start of change Second HPF feature code byte End of change
Start of changeEnd of change Start of change   End of change Start of change 1... .... End of change Start of change 8 End of change Start of change DFAFCX_FmtWrite End of change Start of change Format Write Enable End of change
Start of change 74 (4A) End of change Start of change   End of change Start of change Bit string End of change Start of change 1 End of change Start of change   End of change Start of change Third HPF feature code byte End of change
Start of change 75 (4B) End of change Start of change   End of change Start of change Bit string End of change Start of change 1 End of change Start of change   End of change Start of change Fourth HPF feature code byte End of change
Start of change 76 (4C) End of change Start of change   End of change Start of change Signed End of change Start of change 4 End of change Start of change DFAMAXGN End of change Start of change Maximum Generations supported for this system End of change
Start of change 80 (5C) End of change Start of change   End of change Start of change Unsigned End of change Start of change 1 End of change Start of change DFACMPTYPE End of change Start of change Default compression type. End of change
Start of change   End of change Start of change   End of change Start of change   End of change Start of change   End of change Start of change DFACMPTYPEGEN End of change Start of change 0 = Generic compression End of change
Start of change   End of change Start of change   End of change Start of change   End of change Start of change   End of change Start of change DFACMPTYPETLRD End of change Start of change 1 = Tailored compression End of change
Start of change   End of change Start of change   End of change Start of change   End of change Start of change   End of change Start of change DFACMPTYPEzEDCR End of change Start of change 2 = zEDC compression required End of change
Start of change   End of change Start of change   End of change Start of change   End of change Start of change   End of change Start of change DFACMPTYPEzEDCP End of change Start of change 3 = zEDC compression prefered End of change
Start of change 81 (5D) End of change Start of change   End of change Start of change   End of change Start of change 31 End of change Start of change   End of change Start of change Reserved. End of change
Table 2. DFA Element Name
Offset Type/Value Length Name Description
0(0) DSECT   DFAELNM DSECT name
0(0) UNSIGNED 2 DFAELNML Length of significant characters in next field. Currently ten.
2(2) CHARACTER 22 DFAEXTXT DFSMS element name in EBCDIC. May contain lower case characters. Currently is "z/OS DFSMS".
Parent topic: Control Blocks

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