xref: /freebsd/share/man/man9/pmap_is_modified.9 (revision 02e9120893770924227138ba49df1edb3896112a)
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26.Dd July 17, 2014
27.Dt PMAP_IS_MODIFIED 9
28.Os
29.Sh NAME
30.Nm pmap_is_modified ,
31.Nm pmap_ts_modified
32.Nd return information about physical pages
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_is_modified "vm_page_t m"
39.Ft int
40.Fn pmap_ts_referenced "vm_page_t m"
41.Sh DESCRIPTION
42The
43.Fn pmap_is_modified
44and
45.Fn pmap_ts_referenced
46functions return information about physical pages.
47.Sh RETURN VALUES
48The
49.Fn pmap_is_modified
50function returns the status of the
51.Dq "page modified"
52bit for the physical page
53.Fa m .
54.Pp
55The
56.Fn pmap_ts_referenced
57function returns a count of reference bits for a page
58.Fa m ,
59clearing those bits.
60It is not necessary for every reference bit to be cleared, but it is
61necessary that 0 only be returned when there are no remaining reference
62bits set on the page.
63.Sh SEE ALSO
64.Xr pmap 9 ,
65.Xr pmap_clear_modify 9
66.Sh AUTHORS
67This manual page was written by
68.An Bruce M Simpson Aq Mt bms@spc.org .
69