xref: /freebsd/share/man/man9/vm_map_submap.9 (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
1.\"
2.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
3.\" All rights reserved.
4.\"
5.\" Redistribution and use in source and binary forms, with or without
6.\" modification, are permitted provided that the following conditions
7.\" are met:
8.\" 1. Redistributions of source code must retain the above copyright
9.\"    notice, this list of conditions and the following disclaimer.
10.\" 2. Redistributions in binary form must reproduce the above copyright
11.\"    notice, this list of conditions and the following disclaimer in the
12.\"    documentation and/or other materials provided with the distribution.
13.\"
14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24.\" SUCH DAMAGE.
25.\"
26.\" $FreeBSD$
27.\"
28.Dd July 19, 2003
29.Dt VM_MAP_SUBMAP 9
30.Os
31.Sh NAME
32.Nm vm_map_submap
33.Nd create a subordinate map
34.Sh SYNOPSIS
35.In sys/param.h
36.In vm/vm.h
37.In vm/vm_map.h
38.Ft int
39.Fo vm_map_submap
40.Fa "vm_map_t map" "vm_offset_t start" "vm_offset_t end" "vm_map_t submap"
41.Fc
42.Sh DESCRIPTION
43The
44.Fn vm_map_submap
45function marks the range bounded by
46.Fa start
47and
48.Fa end
49within the map
50.Fa map
51as being handled by a subordinate map
52.Fa sub_map .
53.Pp
54It is generally called by the kernel memory allocator.
55.Sh IMPLEMENTATION NOTES
56This function is for internal use only.
57.Pp
58Both maps must exist.
59The range must have been created with
60.Xr vm_map_find 9
61previously.
62.Pp
63No other operations may have been performed on this range
64before calling this function.
65Only the
66.Fn vm_fault
67operation may be performed within this range after calling
68this function.
69.Pp
70To remove a submapping, one must first remove the range from
71the parent
72.Fa map ,
73and then destroy the
74.Fa sub_map .
75This procedure is not recommended.
76.Sh RETURN VALUES
77The
78.Fn vm_map_submap
79function returns
80.Dv KERN_SUCCESS
81if successful.
82.Pp
83Otherwise, it returns
84.Dv KERN_INVALID_ARGUMENT
85if the caller requested copy-on-write flags,
86or if the range specified for the sub-map was out of range for the parent map,
87or if a
88.Dv NULL
89backing object was specified.
90.Sh SEE ALSO
91.Xr vm_map 9 ,
92.Xr vm_map_find 9
93.Sh AUTHORS
94This manual page was written by
95.An Bruce M Simpson Aq Mt bms@spc.org .
96