The
pmap_extract ();
function maps a virtual address to a physical page.
In certain situations, callers may use
pmap_extract_and_hold ();
instead, to ensure that the returned page is held.
The
pmap_extract_and_hold ();
function maps a virtual address to a physical page, and atomically holds
the returned page for use by the caller, only if the mapping permits
the given page protection.
IMPLEMENTATION NOTES
Currently, the page protection requested by the caller is not verified.
RETURN VALUES
The
pmap_extract ();
function will return the physical page address associated with the
virtual address
Fa va
inside the physical map
Fa pmap .
If the mapping does not exist, or if the
Fa pmap
parameter is
NULL
then
NULL
will be returned.
The
pmap_extract_and_hold ();
function will return the physical page address associated with the
virtual address
Fa va
inside the physical map
Fa pmap .
If the mapping does not exist, the result is a no-op, and
NULL
will
be returned.
An -nosplit
The
pmap_extract_and_hold ();
function was implemented by
An Alan L. Cox Aq alc@imimic.com .
This manual page was written by
An Bruce M Simpson Aq bms@spc.org .