Type ASSEMBLE
Source Lines : 1,476
Fixes Applied : 3
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [HRC106DK]

Module

       DMKPGT

Function

       TO ALLOCATE A PAGE OF DASD SPACE THAT IS TO BE USED FOR EITHER
       VIRTUAL MEMORY PAGING OR FOR SPOOL FILE PAGE BUFFERS

Attributes

       SERIALLY REUSABLE, RESIDENT, CALLED VIA BALR

Operation

       1. POINT TO FIRST DEVICE TYPE ANCHOR FOR OWNED DEVICES

       2. LOCATE THE RDEVBLOK FOR THE NEXT DEVICE WITH TEMPSPACE
          ALLOCATED ON IT

       3. POINT TO THE PROPER RECBLOK ANCHOR (FOR EITHER PAGING OR
          SPOOLING) AND LOCATE THE FIRST RECBLOK WITH AN AVAIL-
          BLE PAGE.  IF A RECBLOK IS FOUND, GO TO STEP 6

       4. IF NO ALLOCATED CYLINDER HAS AN AVAILABLE PAGE, LOCATE THE
          THE NEXT AVAILABLE CYLINDER, WORKING OUTWARD FROM THE
          CENTER OF THE TEMPSPACE AREA.  IF NO CYLINDER IS AVAILABLE,
          GO TO STEP 2; OTHERWISE, CONTINUE

       5. CONSTRUCT A NEW RECBLOK FOR THE ALLOCATED CYLINDER, AND
          CHAIN IT TO THE END OF THE CURRENT CHAIN

       6. CALCULATE THE ADDRESS OF THE ALLOCATED PAGE, MARK IT AS
          ALLOCATED, AND PASS THE ADDRESS BACK TO THE CALLER