Specifications

Operating System Routines
IOC$RELMAPREG
IOC$RELMAPREG
Releases a set of UNIBUS map registers or a set of the first 496 Q22–bus map
registers.
Module
IOSUBNPAG
Macro
RELMPR
Input
Location Contents
R5 Address of UCB
UCB$L_CRB Address of CRB
CRB$L_INTD+
VEC$L_ADP
Address of ADP
CRB$L_INTD+
VEC$W_MAPREG
Starting map register number; VEC$V_MAPLOCK
set indicates that map registers have been
permanently allocated to this controller
CRB$L_INTD+
VEC$B_NUMREG
Number of allocated map registers
ADP$L_MRQFL Head of queue of UCBs waiting for map registers
ADP$W_MRNREGARY,
ADP$W_MRFREGARY,
ADP$L_MRACTMDRS
Map register descriptor arrays
Output
Location Contents
R0 SS$_NORMAL or SS$_SSFAIL
R1, R2 Destroyed
ADP$W_MRNREGARY,
ADP$W_MRFREGARY,
ADP$L_MRACTMDRS
Updated
Synchronization
A driver fork process calls IOC$RELMAPREG at fork IPL, holding the
corresponding fork lock in a multiprocessing environment.
3–119