xref: /freebsd/share/man/man9/vm_map_findspace.9 (revision d37ea99837e6ad50837fd9fe1771ddf1c3ba6002)
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2.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
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26.\" $FreeBSD$
27.\"
28.Dd July 19, 2003
29.Dt vm_map_findspace 9
30.Sh NAME
31.Nm vm_map_findspace
32.Nd find a free region within a map
33.Sh SYNOPSIS
34.In sys/param.h
35.In vm/vm.h
36.In vm/vm_map.h
37.Ft int
38.Fn vm_map_findspace "vm_map_t map" "vm_offset_t start" "vm_size_t length" "vm_offset_t *addr"
39.Sh DESCRIPTION
40The
41.Fn vm_map_findspace
42function attempts to find a region with sufficient space in the
43.Fa map
44for an object of size
45.Fa length
46at the address
47.Fa addr .
48.Sh IMPLEMENTATION NOTES
49It is the caller's responsibility to obtain a lock on the
50.Fa map
51using
52.Xr vm_map_lock 9
53before calling this function.
54.Pp
55This routine may call
56.Xr pmap_growkernel 9
57to grow the kernel's address space, if and only if the mapping is being
58made within the kernel address space, and if insufficient space remains
59in the
60.Dv kernel_map .
61.Sh RETURN VALUES
62The
63.Fn vm_map_findspace
64function returns the value 0 if successful, and
65.Fa *addr
66will contain the first virtual address in the found region;
67otherwise, the value 1 is returned.
68.Sh SEE ALSO
69.Xr pmap_growkernel 9 ,
70.Xr vm_map 9 ,
71.Xr vm_map_lock 9
72.Sh AUTHORS
73This man page was written by
74.An Bruce M Simpson Aq bms@spc.org .
75