xref: /freebsd/share/man/man9/pmap_page_exists_quick.9 (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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26.Dd July 21, 2003
27.Dt PMAP_PAGE_EXISTS_QUICK 9
28.Os
29.Sh NAME
30.Nm pmap_page_exists_quick
31.Nd determine if a page exists in a physical map
32.Sh SYNOPSIS
33.In sys/param.h
34.In vm/vm.h
35.In vm/pmap.h
36.Ft bool
37.Fn pmap_page_exists_quick "pmap_t pmap" "vm_page_t m"
38.Sh DESCRIPTION
39The
40.Fn pmap_page_exists_quick
41function is used to quickly determine if the page
42.Fa m
43exists in the physical map
44.Fa pmap .
45It is typically called from the VM paging code.
46.Sh IMPLEMENTATION NOTES
47The PV count used above may be changed upwards or downwards in future;
48it is only necessary that
49.Dv true
50be returned for a small subset of pmaps for proper page aging.
51.Sh RETURN VALUES
52The
53.Fn pmap_page_exists_quick
54returns
55.Dv true
56only if the PV entry for the physical map
57.Fa pmap
58is one of the first 16 PVs linked from the page
59.Fa m .
60.Sh SEE ALSO
61.Xr pmap 9
62.Sh AUTHORS
63This manual page was written by
64.An Bruce M Simpson Aq Mt bms@spc.org .
65