xref: /freebsd/share/man/man9/vm_map_lookup.9 (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
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26.Dd July 19, 2003
27.Dt VM_MAP_LOOKUP 9
28.Os
29.Sh NAME
30.Nm vm_map_lookup ,
31.Nm vm_map_lookup_done
32.Nd lookup the vm_object backing a given virtual region
33.Sh SYNOPSIS
34.In sys/param.h
35.In vm/vm.h
36.In vm/vm_map.h
37.Ft int
38.Fo vm_map_lookup
39.Fa "vm_map_t *var_map" "vm_offset_t vaddr" "vm_prot_t fault_type"
40.Fa "vm_map_entry_t *out_entry" "vm_object_t *object" "vm_pindex_t *pindex"
41.Fa "vm_prot_t *out_prot" "boolean_t *wired"
42.Fc
43.Ft void
44.Fn vm_map_lookup_done "vm_map_t map" "vm_map_entry_t entry"
45.Sh DESCRIPTION
46The
47.Fn vm_map_lookup
48function attempts to find the
49.Vt vm_object ,
50page index and protection, for the given virtual address
51.Fa vaddr ,
52in the map
53.Fa var_map ,
54assuming a page fault of the type
55.Fa fault_type
56had occurred.
57.Pp
58Return values are guaranteed until
59.Fn vm_map_lookup_done
60is called to release the lock.
61.Sh IMPLEMENTATION NOTES
62The function
63.Fn vm_map_lookup
64acquires a read-lock on the map
65.Fa *var_map ,
66but does not release it.
67The caller should invoke
68.Fn vm_map_lookup_done
69in order to release this lock.
70.Sh RETURN VALUES
71The
72.Fn vm_map_lookup
73function returns
74.Dv KERN_SUCCESS ,
75and sets the
76.Fa *object ,
77.Fa *pindex ,
78.Fa *out_prot ,
79and
80.Fa *out_entry
81arguments appropriately for the hypothetical page fault.
82.Sh SEE ALSO
83.Xr vm_map 9
84.Sh AUTHORS
85This manual page was written by
86.An Bruce M Simpson Aq Mt bms@spc.org .
87