xref: /freebsd/share/man/man9/pmap_page_exists_quick.9 (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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26.\" $FreeBSD$
27.\"
28.Dd July 21, 2003
29.Dt PMAP_PAGE_EXISTS_QUICK 9
30.Os
31.Sh NAME
32.Nm pmap_page_exists_quick
33.Nd determine if a page exists in a physical map
34.Sh SYNOPSIS
35.In sys/param.h
36.In vm/vm.h
37.In vm/pmap.h
38.Ft boolean_t
39.Fn pmap_page_exists_quick "pmap_t pmap" "vm_page_t m"
40.Sh DESCRIPTION
41The
42.Fn pmap_page_exists_quick
43function is used to quickly determine if the page
44.Fa m
45exists in the physical map
46.Fa pmap .
47It is typically called from the VM paging code.
48.Sh IMPLEMENTATION NOTES
49The PV count used above may be changed upwards or downwards in future;
50it is only necessary that
51.Dv TRUE
52be returned for a small subset of pmaps for proper page aging.
53.Sh RETURN VALUES
54The
55.Fn pmap_page_exists_quick
56returns
57.Dv TRUE
58only if the PV entry for the physical map
59.Fa pmap
60is one of the first 16 PVs linked from the page
61.Fa m .
62.Sh SEE ALSO
63.Xr pmap 9
64.Sh AUTHORS
65This manual page was written by
66.An Bruce M Simpson Aq Mt bms@spc.org .
67