NAME
vm_page_free,
vm_page_free_toq,
vm_page_free_zero,
vm_page_try_to_free —
free a page
SYNOPSIS
#include
<sys/param.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
void
vm_page_free(vm_page_t
m);
void
vm_page_free_toq(vm_page_t
m);
void
vm_page_free_zero(vm_page_t
m);
int
vm_page_try_to_free(vm_page_t
m);
DESCRIPTION
Thevm_page_free_toq()
function moves a page into the free queue, and disassociates it from its
object. If the page is held, wired, already free, or its busy count is not
zero, the system will panic. If the PG_ZERO flag is
set on the page, it is placed at the end of the free queue; otherwise, it is
placed at the front.
If the page's object is of type OBJT_VNODE
and it is the last page associated with the object, the underlying vnode may
be freed.
The
vm_page_free()
and
vm_page_free_zero()
functions both call vm_page_free_toq() to actually
free the page, but vm_page_free_zero() sets the
PG_ZERO flag and
vm_page_free() clears the
PG_ZERO flag prior to the call to
vm_page_free_toq().
The
vm_page_try_to_free()
function verifies that the page is not held, wired, busy or dirty, and if
so, marks the page as busy, drops any protection that may be set on the
page, and frees it.
RETURN VALUES
vm_page_try_to_free() returns 1 if it is
able to free the page; otherwise, 0 is returned.
SEE ALSO
AUTHORS
This manual page was written by Chad David <davidc@acns.ab.ca>.