IOCOM mapping

Table 1. Structure IOCOM
Offset Offset
Dec Hex Type Len Name(Dim) Description
0 (0) STRUCTURE 0 IOCOM
0 (0) X'0' 0  IECIXAVL "IOCOM" Compatibility name
0 (0) DBL WORD 8   (0)
0 (0) SIGNED 2  IOCVOICT Number of VOID entries *calculated by IEAIPL03
2 (2) SIGNED 2  IOCVOILN Length of each VOID table entry
4 (4) ADDRESS 4  IOCPST X'80000000'+IECVPST Entry address of the IOS Post Status module
8 (8) ADDRESS 4  IOCOMWPT "V" IECOMW Pointer to modifiable part of IOCOM
12 (C) ADDRESS 4  IOCSSCQ X'80000000'+IOSVSSCQ Entry address for the STARTIO macro
16 (10) ADDRESS 4  IOCMAP X'80000000'+IECVMAP Entry address of the IOSMAP routine
20 (14) ADDRESS 4  IOCSMFRR X'80000000'+IOSVQFRR Address of IOQ Storage Manager FRR routine
24 (18) ADDRESS 4  IOCSCOMP X'80000000'+IOSVSCOM Address of IOS Storage Manager SRB entry compress routine
28 (1C) ADDRESS 4  IOCSTIO X'00000000'+IECVSTIO Entry address of the compatibility STARTIO macro
32 (20) ADDRESS 4  IOCVOID "V" IECVOID Address of vector of IOS drivers
36 (24) ADDRESS 4  IOCIOSSM X'80000000'+IOSVSMGR Start address of the IOS Storage Manager
40 (28) ADDRESS 4  IOCDIRB "V" IOSVIRB Pointer to default error IRB
44 (2C) ADDRESS 4  IOCPRGID X'80000000'+IOSPGRTM Purge Dequeue routine address
48 (30) ADDRESS 4  IOCCHRB "V" IOSVCHRB Pointer to the channel recovery block (IOSDCHRB)
52 (34) ADDRESS 4  IOCISDT "V" IOSVISDT Pointer to the interrupt subclass definition table
56 (38) ADDRESS 4  IOCSWAP X'80000000'+IOSVSWAP Entry address of the SWAP device function
60 (3C) ADDRESS 4  IOCSHUP X'80000000'+IOSVSHUP Entry address of the routine to check for device reservations.
64 (40) ADDRESS 4  IOCOMEX IOSVIOCX Address of the IOCOM extension
68 (44) ADDRESS 4  IOCATTBL "V" IOSVATTN Address of attention table
72 (48) ADDRESS 4  IOCSYNCA "V" IOSVSYLK Address of the IOS Synchronization lock table
76 (4C) ADDRESS 4  IOCCNT X'80000000'+IOSVCNT Entry address of the routine to count requests queued on a UCB
80 (50) ADDRESS 4  IOCHSCH X'80000000'+IOSVHSCH Entry address of the Halt and Clear subchannel routine
84 (54) ADDRESS 4  IOCGENA X'00000000'+IECVGENA Address of IOSGEN subroutine
88 (58) ADDRESS 4  IOCMSCQ X'80000000'+IOSVMSCQ Entry address of the Modify subchannel routine
92 (5C) ADDRESS 4  IOCBHSPCI X'80000000'+BHIP1PCI Entry address of the BHS PCI interface routine
96 (60) ADDRESS 4  IOCSTSQ X'80000000'+IOSVSTSQ Entry address of the Store subchannel routine
100 (64) ADDRESS 4  IOCTCCW X'00000000'+IECVTCCW Address of CCW translator
104 (68) ADDRESS 4  IOCSVCF X'80000000'+IGC015 Entry point of SVC F in the IOS Post Status module
108 (6C) ADDRESS 4  IOCVARY X'80000000'+IOSVVARY Entry address of the Vary routine
112 (70) ADDRESS 4  IOCCNXL X'80000000'+IOSVCNXL Entry address of the cancel request routine
116 (74) ADDRESS 4  IOCQCNT X'00000000'+IECVQCNT Address of purge IPIB quiesce count decrement/post subroutine
120 (78) ADDRESS 4  IOCASCB "V" IEAMASCB ASCB used for scheduling
124 (7C) ADDRESS 4  IOCNSTP Address of the NIP SCHIB table. Set by IEAIPL03, reset by IEAVNP02.
128 (80) ADDRESS 4  IOCIOWA "V" IOSVIOWA Address of IOWA table
132 (84) ADDRESS 2  IOCIOWEL IOWEL Length of IOWA
134 (86) ADDRESS 2  IOCSMGSZ 0 Size of processor related storage
136 (88) ADDRESS 4  IOCCPRM X'80000000'+IOSVCPRM Address of IOS Storage Manager initialization routine
140 (8C) ADDRESS 4  IOCSCP X'80000000'+IOSVSCP Entry address of the start channel-program service routine
144 (90) ADDRESS 4  IOCSIOQC X'80000000'+IOSVIOQC Entry address of the scan- IOQ-chain service routine
148 (94) ADDRESS 4  IOCSDUMP "V" IOSVDUMP Address of the IOS SDUMP parameter list
152 (98) ADDRESS 4  IOCHCRS X'80000000'+IOSVHCRS Address of Halt/Clear resource service routine to free resources tied to the associated start IOSB
156 (9C) ADDRESS 4  IOCZTAB "V" IOSVZTAB Address of module work area table
160 (A0) ADDRESS 4  IOCSMHDR "V" IOSVQHDR Pointer to IOS storage page pool header tables
164 (A4) ADDRESS 4  IOCSMLG X'80000000'+IOSVSMLG Address of IOS Storage Manager get large block entry
168 (A8) ADDRESS 4  IOCSMLF X'80000000'+IOSVSMLF Address of IOS Storage Manager free large block entry
172 (AC) ADDRESS 4  IOCSMPF X'80000000'+IOSVSMPF Address of IOS Storage Manager purge/free entry
176 (B0) ADDRESS 4  IOCSMMG X'80000000'+IECVSMMG Address of IOS Storage Manager EXCP get RQE (medium) block entry
180 (B4) ADDRESS 4  IOCSMMF X'80000000'+IECVSMMF Address of IOS Storage Manager EXCP free RQE (medium) block entry
184 (B8) ADDRESS 4  IOCSMEG X'80000000'+IECVSMEG Address of IOS Storage Manager EXCP get large block entry
188 (BC) ADDRESS 4  IOCSMEF X'80000000'+IECVSMEF Address of IOS Storage Manager EXCP free large block entry
192 (C0) ADDRESS 4  IOCDPTH X'80000000'+IECVDPTH Address of Dynamic Pathing module
196 (C4) ADDRESS 4  IOCLEVL X'00000000'+IOSVLEVL Entry address of the IOS Level routine
200 (C8) ADDRESS 4  IOCRSUM X'00000000'+IOSVRSUM Entry address of the Resume I/O routine
204 (CC) ADDRESS 4  IOCEXHDR "V" IECVSHDR Pointer to EXCP storage page pool header tables
208 (D0) ADDRESS 4  IOCIOVTP "V" IOVT Address of IOS Vector Table (IOVT)
212 (D4) ADDRESS 4  IOCDPSV X'80000000'+IOSRDPSV DPS Validation
216 (D8) ADDRESS 4  IOCBIND X'80000000'+IOSVBIND IOS PAV BIND Service
220 (DC) ADDRESS 4  IOCSCMT X'80000000'+IOSCSCMT IOS SCMT services
224 (E0) ADDRESS 4  IOCCMB X'80000000'+IOSVCMB IOS CMB Service
228 (E4) ADDRESS 4  IOCHSWP X'80000000'+IOSVHSWP IOS Hyperswap Initiation Service
232 (E8) BITSTRING 1  IOCDDRLV DDR Level. Initialized by IOS Storage Manager at NIP.
233 (E9) BITSTRING 3   Available
236 (EC) ADDRESS 4  IOCCSTK X'80000000'+IOSVCSTK IOS CPU Stack Service
240 (F0) ADDRESS 4  IOCFBND X'80000000'+IOSVFBND IOS Fast BIND Service
244 (F4) ADDRESS 4  IOCRSV4(6) Reserved
268 (10C) ADDRESS 4  IOCLVTBL "V" IOSVLVTB Pointer to the IOS level table
272 (110) BITSTRING 1  IOCFLAGS IOCOM flag and ID byte
  1... ....  IOCSINTC "X'80'" IEAVNP02 subchannel initialization complete (set by IEAVNP02)
  .1.. ....  IOCIODF "X'40'" IPL sets on if the IODF IPL path was used.
  ..1. ....  IOCCRWE "X'20'" IEAVNP02 sets on when enabling for CRWs.
  ...1 ....  IOCPAVS "X'10'" PAVs are supported
  .... 1...  IOCEMW "X'08'" Extended I/O measurement word facility is enabled
  .... .1..  IOCMCSS "X'04'" The multiple channel subsystem (MCSS) facility is supported by the hardware
272 (110) X'110' 0  IOCHSSID "IOCFLAGS+0,1" Highest subchannel set ID in use (bits 6-7)
273 (111) BITSTRING 1  IOCQSCLV Quiesce level. Initialized by IOS Storage Manager at NIP time
274 (112) BITSTRING 1  IOCIOQVR IOQ Version number
  .... ...1  IOCIOQV1 "X'01'" IOQ Version 1. The IOQ has 92 bytes workarea for the device dependent exits
275 (113) BITSTRING 1  IOCCSSID Default channel subsystem id for this logical partition
276 (114) ADDRESS 4  IOCIOQSQ "V" IOSVIOSQ Address of IOS Storage Manager IOQ staging queue table
280 (118) ADDRESS 4  IOCFDEV X'80000000'+IOSRFDEV Address of force device SRB routine
284 (11C) ADDRESS 4  IOCACRW X'80000000'+IOSRACRW Address of asynchronous CRW processor
288 (120) ADDRESS 4  IOCHIDT "V" IOSRHIDT Address of the Hot I/O detection table
292 (124) ADDRESS 4  IOCSCHNO IECVGENA+X'0000001C' Address of the Subchannel number service routine in IECVGENA
296 (128) ADDRESS 4  IOCIPID IOSVIPID Address of the I/O prevention identifier service routine- IOSVIPID
300 (12C) ADDRESS 4  IOCPRVT IOSVPRVT Address of the I/O Prevention service routine - IOSVPRVT
304 (130) ADDRESS 4  IOCURGC IOSPURGC Address of the branch entry - IOSPURGC.
308 (134) ADDRESS 4  IOCRERPT Address of the resident ERP - table. (valid if IOCIODF is off)
312 (138) ADDRESS 4  IOCCDTSR X'80000000'+IOSCCDT Address of configuration data table service routine
316 (13C) ADDRESS 4  IOCCUIR X'80000000'+IOSVCUIR Address of CUIR service routine
320 (140) ADDRESS 4  IOCSLFD X'80000000'+IOSVSLFD Address of self description service routine
324 (144) ADDRESS 4  IOCSLFI X'80000000'+IOSVSLFI Address of self description initialization routine
328 (148) ADDRESS 4  IOCIMSGA X'80000000'+IMSGARRY Address of IOS message array
332 (14C) ADDRESS 4  IOCMIHQ X'80000000'+IOSVMIHQ Address of the MIH query service routine
336 (150) ADDRESS 4  IOCMANI X'80000000'+IOSVMANI Address of the IOS manual intervention service routine
340 (154) ADDRESS 4  IOCCSCM X'80000000'+IOSRCSCM Address of CSCM service routine
344 (158) ADDRESS 4  IOCBHICT X'80000000'+BHIT2RCD Address of BHI CTrace non BHIHSRV entry point
344 (158) X'15C' 0  IOCOEND "*" End of the read only section of the IOCOM
Table 2. Structure IOCOMW
Offset Offset
Dec Hex Type Len Name(Dim) Description
0 (0) STRUCTURE 0 IOCOMW Modifiable part of IOCOM
0 (0) DBL WORD 8   (0) 
                                   (Addressed by IOCOMWPT)
0 (0) CHARACTER 4  IOCIOCW Acronym for modifiable section of the IOCOM ('IOCW')
4 (4) ADDRESS 2  IOCLENW Length of the modifiable section of the IOCOM
6 (6) SIGNED 2  IOCPGCT Number of active I/O purges
8 (8) DBL WORD 8  IOCHTFLD(0)
8 (8) ADDRESS 4  IOCSLIH X'80000000'+IOSVSLIH Pointer to the second level interrupt handler or the IOS interrupt trap routine. This field will also have an external label of IECSLIHA.
12 (C) SIGNED 4  IOCHOTCT Count of Hot Devices. If this field is not zero, IOCSLIH will point to the HOT I/O SLIH
16 (10) ADDRESS 4  IOCMIHCA MIHATBLE Address of the MIH work area. Prior to MIH initialization the first two bytes of the MIH work area are set to blanks. After MIH initialization, these two bytes are set to **.
20 (14) ADDRESS 4  IOCIOPTA Address of the I/O Prevention table (IOPT).
24 (18) SIGNED 2  IOCIOPTC Count of the number of IOPT table entries.
26 (1A) SIGNED 2  IOCSSCBT SSCB token updated everytime an SSCB is added or deleted from theCDT SSCB chain. This allows services like SSCBSCAN to check for SSCB changes.
28 (1C) ADDRESS 4  IOCCDT Pointer to configuration data table
32 (20) ADDRESS 4  IOCCPAT Pointer to channel path attribute table
36 (24) ADDRESS 4  IOCCUIRQ Pointer to CUIR request queue
40 (28) SIGNED 4  IOCSLFCT Counter used during self description initialization to keep track of the number of devices being initialized
44 (2C) ADDRESS 1  IOCFLAG2 Flag byte. Note: IOCIOSHSWAP is initialized to '1'b and is never reset.
  1... ....  IOCSLFSD "X'80'" Indicates that scan of UCBs during self description initialization is done
  .1.. ....  IOCCDTIN "X'40'" Indicates that CDT is initialized
  ..1. ....  IOCCULA "X'20'" Indicates that the CULAs are initialized
  ...1 ....  IOCUPCDS "X'10'" If ON, indicates the that IOS record in the couple dataset has been updated.
  .... 1...  IOCGDPSHSWAP2 "X'08'" If ON, indicates that the GDPS Hyperswap Stage II environment exists, including: - Unplanned outage support - Recognition of ENF-63 as a trigger Specifically, this bit is on when the HS API address space is up and has a configuration.
  .... .1..  IOCDAOTH "X'04'" If ON, indicates that the "Device Active Only" time in the CMB is supported by the hardware
  .... ..1.  IOCIOSHSWAP "X'02'" If ON, indicates that the IOS Hyperswap environment exists
  .... ...1  IOCGDPSHSWAP "X'01'" If ON, indicates that the GDPS Hyperswap environment exists and is available
45 (2D) ADDRESS 1  IOCFLAG3 Flag byte. Note: IOCODS and IOCPREFPATHS are initialized to '1'b and never reset
  1... ....  IOCODS "X'80'" Offline Device Services are supported
  .1.. ....  IOCDPINC "X'40'" If ON, indicates that dynamic pathing initialization processing is complete for all online devices. (set by IECVIOSI)
  ..1. ....  IOCJES3HSWAP "X'20'" If ON, indicates that JES3 supports hyperswaps (Set by JES3).
  ...1 ....  IOCPREFPATHS "X'10'" If ON, preferred pathing is supported by IOS.
  .... 1...  IOCGDPSIOT "X'08'" If ON, indicates that GDPS supports the IO Timing trigger for HyperSwap
  .... .1..  IOCINBAND "X'04'" If ON, indicates that in-band Key management is preferred
  .... ..1.  IOCGDPSHSWPACT "X'02'" If ON, indicates that a HyperSwap is in the process of being performed
  .... ...1  IOCGDPSHSWPCLN "X'01'" If ON, indicates that HyperSwap is in the process of post swap cleanup
46 (2E) BITSTRING 2   Reserved
48 (30) ADDRESS 4  IOCPURGQ Anchor for global queue of Purge Quiesce IPIBs. Serialized via the IOSYNCH lock.
52 (34) ADDRESS 4  IOCPAVE "V(PAVE)" Anchor for PAV Exit Table
56 (38) ADDRESS 4  IOCIECAA "V(IECA)" Address of IOS Extended Communication Area
60 (3C) SIGNED 4  IOCCADSALET CADS Alet
64 (40) SIGNED 4  IOCFLAG4(0) Flag Word
64 (40) BITSTRING 1  IOCFLG4A Flag Byte
  1... ....  IOCHPAV "X'80'" On, HYPERPAV=YES
  .1.. ....  IOCHPBO "X'40'" On, HYPERPAV=BASEONLY
  ..1. ....  IOCHPAVD "X'20'" On, at least one LSS is in HYPERPAV mode
  ...1 ....  IOCZHPFIL "X'10'" zHPF incorrect length support provided by the processor
  .... 1...  IOCSWAPMGRSETSSYSCANHSWAP "X'08'" 0-There is no hyperswap manager or the hyperswap manager does not support the IOCSystemCanHyperSwap flag 1-The hyperswap manager supports the IOCSystemCanHyperSwap flag
  .... .1..  IOCSYSTEMCANHYPERSWAP "X'04'" 0-The sysplex and/or this system is currently not enabled for hyperswap 1-The sysplex and this system are currently enabled for hyperswap
65 (41) BITSTRING 3   Reserved
68 (44) ADDRESS 4  IOC_BHS_CSMARRAY@ Address of the BHS CsmArray
72 (48) BITSTRING 4   Reserved
72 (48) X'4C' 0  IOCENDW "*" End of the modifiable section of the IOCOM
Table 3. Cross Reference for IOCOM
Name Offset Hex Tag  
IECIXAVL 0 0  
IOC_BHS_CSMARRAY@ 44  
IOCACRW 11C  
IOCASCB 78  
IOCATTBL 44  
IOCBHICT 158  
IOCBHSPCI 5C  
IOCBIND D8  
IOCCADSALET 3C  
IOCCDT 1C  
IOCCDTIN 2C 40  
IOCCDTSR 138  
IOCCHRB 30  
IOCCMB E0  
IOCCNT 4C  
IOCCNXL 70  
IOCCPAT 20  
IOCCPRM 88  
IOCCRWE 110 20  
IOCCSCM 154  
IOCCSSID 113  
IOCCSTK EC  
IOCCUIR 13C  
IOCCUIRQ 24  
IOCCULA 2C 20  
IOCDAOTH 2C 4  
IOCDDRLV E8  
IOCDIRB 28  
IOCDPINC 2D 40  
IOCDPSV D4  
IOCDPTH C0  
IOCEMW 110 8  
IOCENDW 48 4C  
IOCEXHDR CC  
IOCFBND F0  
IOCFDEV 118  
IOCFLAGS 110  
IOCFLAG2 2C  
IOCFLAG3 2D  
IOCFLAG4 40  
IOCFLG4A 40  
IOCGDPSHSWAP 2C 1  
IOCGDPSHSWAP2 2C 8  
IOCGDPSHSWPACT 2D 2  
IOCGDPSHSWPCLN 2D 1  
IOCGDPSIOT 2D 8  
IOCGENA 54  
IOCHCRS 98  
IOCHIDT 120  
IOCHOTCT C  
IOCHPAV 40 80  
IOCHPAVD 40 20  
IOCHPBO 40 40  
IOCHSCH 50  
IOCHSSID 110 110  
IOCHSWP E4  
IOCHTFLD 8  
IOCIECAA 38  
IOCIMSGA 148  
IOCINBAND 2D 4  
IOCIOCW 0  
IOCIODF 110 40  
IOCIOPTA 14  
IOCIOPTC 18  
IOCIOQSQ 114  
IOCIOQVR 112  
IOCIOQV1 112 1  
IOCIOSHSWAP 2C 2  
IOCIOSSM 24  
IOCIOVTP D0  
IOCIOWA 80  
IOCIOWEL 84  
IOCIPID 128  
IOCISDT 34  
IOCJES3HSWAP 2D 20  
IOCLENW 4  
IOCLEVL C4  
IOCLVTBL 10C  
IOCMANI 150  
IOCMAP 10  
IOCMCSS 110 4  
IOCMIHCA 10  
IOCMIHQ 14C  
IOCMSCQ 58  
IOCNSTP 7C  
IOCODS 2D 80  
IOCOEND 158 15C  
IOCOM 0  
IOCOMEX 40  
IOCOMW 0  
IOCOMWPT 8  
IOCPAVE 34  
IOCPAVS 110 10  
IOCPGCT 6  
IOCPREFPATHS 2D 10  
IOCPRGID 2C  
IOCPRVT 12C  
IOCPST 4  
IOCPURGQ 30  
IOCQCNT 74  
IOCQSCLV 111  
IOCRERPT 134  
IOCRSUM C8  
IOCRSV4 F4  
IOCSCHNO 124  
IOCSCMT DC  
IOCSCOMP 18  
IOCSCP 8C  
IOCSDUMP 94  
IOCSHUP 3C  
IOCSINTC 110 80  
IOCSIOQC 90  
IOCSLFCT 28  
IOCSLFD 140  
IOCSLFI 144  
IOCSLFSD 2C 80  
IOCSLIH 8  
IOCSMEF BC  
IOCSMEG B8  
IOCSMFRR 14  
IOCSMGSZ 86  
IOCSMHDR A0  
IOCSMLF A8  
IOCSMLG A4  
IOCSMMF B4  
IOCSMMG B0  
IOCSMPF AC  
IOCSSCBT 1A  
IOCSSCQ C  
IOCSTIO 1C  
IOCSTSQ 60  
IOCSVCF 68  
IOCSWAP 38  
IOCSWAPMGRSETSSYSCANHSWAP 40 8  
IOCSYNCA 48  
IOCSYSTEMCANHYPERSWAP 40 4  
IOCTCCW 64  
IOCUPCDS 2C 10  
IOCURGC 130  
IOCVARY 6C  
IOCVOICT 0  
IOCVOID 20  
IOCVOILN 2  
IOCZHPFIL 40 10  
IOCZTAB 9C  
Parent topic: IOCOM Information