pmap_page_exists_quick(9)
determine if a page exists in a physical map
SYNOPSIS
In sys/param.h
In vm/vm.h
In vm/pmap.h
Ft boolean_t
Fn pmap_page_exists_quick pmap_t pmap vm_page_t m
DESCRIPTION
The
Fn pmap_page_exists_quick
function is used to quickly determine if the page
Fa m
exists in the physical map
Fa pmap .
It is typically called from the VM paging code.
IMPLEMENTATION NOTES
The PV count used above may be changed upwards or downwards in future;
it is only necessary that
TRUE
be returned for a small subset of pmaps for proper page aging.
RETURN VALUES
The
Fn pmap_page_exists_quick
returns
TRUE
only if the PV entry for the physical map
Fa pmap
is one of the first 16 PVs linked from the page
Fa m .
