freebsd-skq/share/man/man9/pmap_change_wiring.9
2004-07-05 18:13:50 +00:00

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.Dd July 21, 2003
.Dt PMAP_CHANGE_WIRING 9
.Sh NAME
.Nm pmap_change_wiring
.Nd change physical wiring for a map or virtual address pair
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/pmap.h
.Ft void
.Fn pmap_change_wiring "pmap_t pmap" "vm_offset_t va" "boolean_t wired"
.Sh DESCRIPTION
The
.Fn pmap_change_wiring
function changes the wiring attribute for the page at virtual address
.Fa va
in the physical map
.Fa pmap .
A wired page gets its name from being
.Dq wired
into the system page tables so that it will not be paged out.
.Pp
The mapping must already exist in the
.Fa pmap .
If
.Fa wired
is
.Dv TRUE ,
the map's wired page count will be incremented; if
.Dv FALSE ,
it will be decremented.
.Pp
It is typically called by the
.Fn vm_fault_unwire
function.
.Sh SEE ALSO
.Xr pmap 9
.Sh AUTHORS
This manual page was written by
.An Bruce M Simpson Aq bms@spc.org .