as_seth Kernel Service

Kernel and Subsystems Technical Reference, Volume 1

as_seth Kernel Service

Purpose

Maps a specified region in the specified address space for the specified virtual memory object.

Syntax

#include <sys/types.h>
#include <sys/errno.h>
#include <sys/vmuser.h>
#include <sys/adspace.h>

void as_seth (adspacep, vmhandle, addr)
adspace_t *adspacep;
vmhandle_t vmhandle;
caddr_t addr;

Parameters

adspacep	Points to the address space structure that defines the address space where the region for the virtual memory object is to be allocated. The getadsp kernel service can obtain this pointer.
vmhandle	Describes the virtual memory object being made addressable within a region of the specified address space.
addr	Specifies the virtual memory address which identifies the region of the specified address space to allocate. On this system, the upper 4 bits of this address are used to determine which region to allocate.

Description

The as_seth kernel service:

Allocates the region within the address space specified by the adspacep parameter and the addr parameter. Any virtual memory object previously mapped in this region of the address space is unmapped.
Maps the virtual memory object selected by the vmhandle parameter with the access permission specified in the handle.

The as_seth kernel service should only be used when it is necessary to map a virtual memory object at a fixed address within an address space. The as_att kernel service should be used when it is not absolutely necessary to map the virtual memory object at a fixed address.

Execution Environment

The as_seth kernel service can be called from the process environment only.

Return Values

The as_seth kernel service always succeeds and returns nothing.

Implementation Specifics

The as_seth kernel service is part of the Base Operating System (BOS) Runtime.

Related Information

The getadsp kernel service, as_att kernel service, vm_att kernel service, as_geth kernel service, and as_getsrval kernel service.