xref: /freebsd/share/man/man9/vm_map_lock.9 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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26.Dd July 19, 2003
27.Dt VM_MAP_LOCK 9
28.Os
29.Sh NAME
30.Nm vm_map_lock ,
31.Nm vm_map_unlock ,
32.Nm vm_map_lock_read ,
33.Nm vm_map_unlock_read ,
34.Nm vm_map_trylock ,
35.Nm vm_map_trylock_read ,
36.Nm vm_map_lock_upgrade ,
37.Nm vm_map_lock_downgrade
38.Nd vm_map locking macros
39.Sh SYNOPSIS
40.In sys/param.h
41.In vm/vm.h
42.In vm/vm_map.h
43.Ft void
44.Fn vm_map_lock "vm_map_t map"
45.Ft void
46.Fn vm_map_unlock "vm_map_t map"
47.Ft void
48.Fn vm_map_lock_read "vm_map_t map"
49.Ft void
50.Fn vm_map_unlock_read "vm_map_t map"
51.Ft int
52.Fn vm_map_trylock "vm_map_t map"
53.Ft int
54.Fn vm_map_trylock_read "vm_map_t map"
55.Ft int
56.Fn vm_map_lock_upgrade "vm_map_t map"
57.Ft int
58.Fn vm_map_lock_downgrade "vm_map_t map"
59.Sh DESCRIPTION
60The
61.Fn vm_map_lock
62macro obtains an exclusive lock on
63.Fa map .
64.Pp
65The
66.Fn vm_map_unlock
67macro releases an exclusive lock on
68.Fa map .
69.Pp
70The
71.Fn vm_map_lock_read
72macro obtains a read-lock on
73.Fa map .
74.Pp
75The
76.Fn vm_map_unlock_read
77macro releases a read-lock on
78.Fa map .
79.Pp
80The
81.Fn vm_map_trylock
82macro attempts to obtain an exclusive lock on
83.Fa map .
84It returns FALSE if the lock cannot be immediately acquired;
85otherwise return TRUE with the lock acquired.
86.Pp
87The
88.Fn vm_map_trylock_read
89macro attempts to obtain a read-lock on
90.Fa map .
91It returns FALSE if the lock cannot be immediately acquired;
92otherwise return TRUE with the lock acquired.
93.Pp
94The
95.Fn vm_map_lock_upgrade
96macro attempts to atomically upgrade a read-lock on
97.Fa map
98to an exclusive lock.
99.Pp
100The
101.Fn vm_map_lock_downgrade
102macro attempts to downgrade an exclusive lock on
103.Fa map
104to a read-lock.
105.Sh IMPLEMENTATION NOTES
106Currently, all of the locking macros implement their locks as sleep locks.
107.Sh SEE ALSO
108.Xr vm_map 9
109.Sh AUTHORS
110This manual page was written by
111.An Bruce M Simpson Aq Mt bms@spc.org .
112