freebsd-dev/share/man/man9/pmap_init.9
Bruce M Simpson 8019c643f1 Add manual page documentation for the machine-independent PMAP subsystem.
Include documentation of alc's new pmap_extract_and_hold() function.

Reviewed by:	hmp
Approved by:	jake (mentor)
2003-09-25 19:14:40 +00:00

73 lines
2.4 KiB
Groff

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.Dd July 21, 2003
.Dt PMAP_INIT 9
.Sh NAME
.Nm pmap_init ,
.Nm pmap_init2
.Nd initialize the pmap subsystem
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/pmap.h
.Ft void
.Fn pmap_init "vm_paddr_t phys_start" "vm_paddr_t phys_end"
.Ft void
.Fn pmap_init2 "void"
.Sh DESCRIPTION
The
.Fn pmap_init
function initializes the
.Xr pmap 9
sub-system.
It is called during system initialization by
.Fn vm_init ,
to initialize any structures that the
.Nm
system needs in order to map between physical and virtual memory.
.Pp
The
.Fn pmap_init
supports discontiguous physical memory in a fairly consistent way.
The module will manage the range of physical pages between
.Fa phys_start
and
.Fa phys_end .
.Pp
The
.Fn pmap_init2
function initializes a zone for the PV entries.
These are used to implement page sharing at the physical level.
A high water mark is set so that the system can recover from
excessive numbers of PV entries.
.Sh SEE ALSO
.Xr pmap 9
.Sh AUTHORS
This manual page was written by
.An Bruce M Simpson Aq bms@spc.org .