xref: /freebsd/share/man/man9/pmap_is_modified.9 (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99)
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26.\" $FreeBSD$
27.\"
28.Dd July 17, 2014
29.Dt PMAP_IS_MODIFIED 9
30.Os
31.Sh NAME
32.Nm pmap_is_modified ,
33.Nm pmap_ts_modified
34.Nd return information about physical pages
35.Sh SYNOPSIS
36.In sys/param.h
37.In vm/vm.h
38.In vm/pmap.h
39.Ft boolean_t
40.Fn pmap_is_modified "vm_page_t m"
41.Ft int
42.Fn pmap_ts_referenced "vm_page_t m"
43.Sh DESCRIPTION
44The
45.Fn pmap_is_modified
46and
47.Fn pmap_ts_referenced
48functions return information about physical pages.
49.Sh RETURN VALUES
50The
51.Fn pmap_is_modified
52function returns the status of the
53.Dq "page modified"
54bit for the physical page
55.Fa m .
56.Pp
57The
58.Fn pmap_ts_referenced
59function returns a count of reference bits for a page
60.Fa m ,
61clearing those bits.
62It is not necessary for every reference bit to be cleared, but it is
63necessary that 0 only be returned when there are no remaining reference
64bits set on the page.
65.Sh SEE ALSO
66.Xr pmap 9 ,
67.Xr pmap_clear_modify 9
68.Sh AUTHORS
69This manual page was written by
70.An Bruce M Simpson Aq Mt bms@spc.org .
71