xref: /freebsd/share/man/man9/pmap_qenter.9 (revision 63a938566d524836885917d95bd491aa4400b181)
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26.\" $FreeBSD$
27.\"
28.Dd February 15, 2018
29.Dt PMAP_QENTER 9
30.Os
31.Sh NAME
32.Nm pmap_qenter ,
33.Nm pmap_qremove
34.Nd manage temporary kernel space mappings
35.Sh SYNOPSIS
36.In sys/param.h
37.In vm/vm.h
38.In vm/pmap.h
39.Ft void
40.Fn pmap_qenter "vm_offset_t sva" "vm_page_t *m" "int count"
41.Ft void
42.Fn pmap_qremove "vm_offset_t sva" "int count"
43.Sh DESCRIPTION
44The
45.Fn pmap_qenter
46function accepts a linear array of
47.Fa count
48pointers to wired pages
49.Fa *m ,
50and enters each of these pages into the kernel virtual address (KVA) space,
51beginning at the address
52.Fa sva .
53The pages are mapped non-executable, if possible.
54(For example, non-PAE i386 has no capability to map pages non-executable.)
55.Pp
56The
57.Fn pmap_qremove
58function tears out a mapping from the kernel virtual address space,
59beginning at
60.Fa sva
61and for
62.Fa count
63pages.
64.Sh IMPLEMENTATION NOTES
65The
66.Fn pmap_qenter
67function is intended for temporary mappings that do not require page
68modification or reference counting.
69Old mappings are simply overwritten.
70The pages
71.Em must
72be wired into physical memory.
73.Pp
74The corresponding
75.Fn pmap_qremove
76function is intended to remove such temporary mappings.
77.Sh SEE ALSO
78.Xr pmap 9
79.Sh AUTHORS
80This manual page was written by
81.An Bruce M Simpson Aq Mt bms@spc.org .
82