Specifications

Operating System Routines

EXE$DEANONPAGED, EXE$DEANONPGDSIZ

Deallocates a block of memory and returns it to nonpaged pool.

Module

MEMORYALC

Input

Location Contents

R0 Address of block to be deallocated

R1 Size of block in bytes, if from variable pool

(EXE$DEANONPGDSIZ only)

IRP$W_SIZE Size of block in bytes (EXE$DEANONPAGED only)

IRP$B_TYPE Type of block to be deallocated

(EXE$DEANONPAGED only)

Note

The MSB of ﬁeld IRP$B_TYPE must be zero, unless it is deﬁnning a

shared memory structure.

Output

Location Contents

R1 and R2 Destroyed

Synchronization

EXE$DEANONPAGED and EXE$DEANONPGDSIZ execute at the caller’s IPL,

at IPL$_SYNCH holding the SCHED spinlock, and at IPL$_POOL holding the

POOL spinlock. As a result, the caller cannot be executing above IPL$_SYNCH.

EXE$DEANONPAGED and EXE$DEANONPGDSIZ return control to the caller

at the caller’s IPL. The caller retains any spinlocks it held at the time of the call.

Description

EXE$DEANONPAGED and EXE$DEANONPGDSIZ deallocate the speciﬁed block

of memory to nonpaged dynamic memory, returning it to a lookaside list or the

variable region of nonpaged pool as appropriate. These routines also report to the

scheduler the availability of the deallocated pool.

EXE$DEANONPAGED issues a BADDALRQSZ bugcheck if the address of the

pool to be deallocated is not aligned on a 16-byte boundary.

If enabled by the SYSGEN parameter POOLCHECK, these routines overwrite

portions of the deallocated pool with a checksum and a one-byte pattern. This

action is helpful when tracking pool corruption problems.

Do not expect R0 to give good status upon returning, if it fails system bugchecked.

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