w .. SIO From Virtual Machine! DMKVSP INpUT-----------------, GR2 Virtual CAW ___ Virtual Storage
VOEVBLOK VOEVSPL VOEVCSW If spool file not open,
create VSPLCTL get virtual buffer
save data in VSPLCTL If Printer" Punch, or Console fa get a work buffer
get virtual CCW move logical record (CCW and data) from spool buffer to work buffer
move data to user's data area
post 'interrupt' pending and return to virtual machine If a Card Reader
get a work buffer
get virtual CCW move logical record (CCW and data) from spool buffer to work buffer
move data to virtual data area
post 'interrupt' pending and return to virtual machine.
r-------------------------------------.-----------------------------, Virtual console spooling is the same as printer spooling except that: • A skip to channel one CCW is inserted every 60 lines of output • The operator's virtual console spool buffer is written for every 161ines of output • The Virtual spool buffer is written.to the allocated spool device when the first CCW is placed in the Virtual buffer. The buffer is kept in a pseudo closed state so that checkpoint saves the buffer in the event of a system failure. OUTPUT -------------""1 Real Storage WORK
Free
Storage
Area
User's virtual machine
"'ltI I ..... I\.) \Q I\.) ,::;: H (I) H txt \D IX c:a IX !::tJ INPUT FOR PUNCH/PRINTER " (I) W I» RDEVBLOK ..... 0 en en to a..cs 0 en 0 r+ (I) ..... • ::s !"Q t-4 0 \Q ..... 0 I» SFBUSER t:S SFBCLAS Pol SFBCOPY 1'0 H 0 D" «D II t=' INPUT FOR READER «D 10BLOK r+ «D H • ..... t:S I» CJ r+ ..... 0 t:S I I c:a 0 d • «D • Interrupt From Spool Device 1----- PROCESS ------- ...... Find nonbusy unit record device
Find SFBLOK for that device type
Create RSPLCTL block and chain it to RDEVBLOK
Remove SFBLOK from chain and chain it to RSPLCTL Get virtual buffer and read DASD page
Reconstruct CCWs in data page
Create 10BLOK and chain CCWs to 10BLOK Schedule I/O operation
When there is an interrupt from the
unit-record device, get next DASD
page from chain ,-------- OUTPUT FOR PUNCH/PRINTER -------. RDEVBLm RDEVSTAT RDEVTYC RDEVSPL SPUNK CCWs Data
Data TIC ( TIC OR CJ FOR Real Stot-age DASD Auxiliary Storage SPOOL BtFFER
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