vm_page_free(9)

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

The vm_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

vm_page_busy(9), vm_page_hold(9), vm_page_wire(9)

AUTHORS

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

ns.ab.ca>.

BSD July 24, 2001

BSD