vm_page_protect(9)

NAME

vm_page_protect - lower a page's protection

SYNOPSIS

#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
void
vm_page_protect(vm_page_t mem, int prot);

DESCRIPTION

The vm_page_protect() function lowers a page's protection.

The protection is never raised by this function; therefore, if the

page is already
at VM_PROT_NONE, the function does nothing.

Its arguments are:

mem The page whose protection is lowered.

prot The protection the page should be reduced to. If

VM_PROT_NONE

is specified, then the PG_WRITABLE and PG_MAPPED

flags are
cleared and the pmap_page's protection is set to

VM_PROT_NONE.
If VM_PROT_READ is specified, then the PG_WRITABLE

flag is
cleared and the pmap_page's protection is set to

VM_PROT_READ.

Higher protection requests are ignored.

AUTHORS

This manual page was written by Chad David <davidc@ac

ns.ab.ca>.

BSD July 14, 2001

BSD