xref: /freebsd/share/man/man9/pmap_page_exists_quick.9 (revision 2357939bc239bd5334a169b62313806178dd8f30)
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26.\" $FreeBSD$
27.\"
28.Dd July 21, 2003
29.Dt PMAP_PAGE_EXISTS_QUICK 9
30.Sh NAME
31.Nm pmap_page_exists_quick
32.Nd determine if a page exists in a physical map
33.Sh SYNOPSIS
34.In sys/param.h
35.In vm/vm.h
36.In vm/pmap.h
37.Ft boolean_t
38.Fn pmap_page_exists_quick "pmap_t pmap" "vm_page_t m"
39.Sh DESCRIPTION
40The
41.Fn pmap_page_exists_quick
42function is used to quickly determine if the page
43.Fa m
44exists in the physical map
45.Fa pmap .
46It is typically called from the VM paging code.
47.Sh RETURN VALUES
48The
49.Fn pmap_page_exists_quick
50returns
51.Dv TRUE
52only if the PV entry for the physical map
53.Fa pmap
54is one of the first 16 PVs linked from the page
55.Fa m .
56.Sh IMPLEMENTATION NOTES
57The PV count used above may be changed upwards or downwards in future;
58it is only necessary that
59.Dv TRUE
60be returned for a small subset of pmaps for proper page aging.
61.Sh SEE ALSO
62.Xr pmap 9
63.Sh AUTHORS
64This manual page was written by
65.An Bruce M Simpson Aq bms@spc.org .
66