1 /*-
2 * Copyright (c) 2002, Jeffrey Roberson <jeff@freebsd.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 unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/9/sys/sys/umtx.h 234371 2012-04-17 09:02:55Z davidxu $
27 *
28 */
29
30 #ifndef _SYS_UMTX_H_
31 #define _SYS_UMTX_H_
32
33 #include <sys/_umtx.h>
34 #include <sys/limits.h>
35
36 #define UMTX_UNOWNED 0x0
37 #define UMTX_CONTESTED LONG_MIN
38
39 #define USYNC_PROCESS_SHARED 0x0001 /* Process shared sync objs */
40
41 #define UMUTEX_UNOWNED 0x0
42 #define UMUTEX_CONTESTED 0x80000000U
43
44 #define UMUTEX_ERROR_CHECK 0x0002 /* Error-checking mutex */
45 #define UMUTEX_PRIO_INHERIT 0x0004 /* Priority inherited mutex */
46 #define UMUTEX_PRIO_PROTECT 0x0008 /* Priority protect mutex */
47
48 /* urwlock flags */
49 #define URWLOCK_PREFER_READER 0x0002
50
51 #define URWLOCK_WRITE_OWNER 0x80000000U
52 #define URWLOCK_WRITE_WAITERS 0x40000000U
53 #define URWLOCK_READ_WAITERS 0x20000000U
54 #define URWLOCK_MAX_READERS 0x1fffffffU
55 #define URWLOCK_READER_COUNT(c) ((c) & URWLOCK_MAX_READERS)
56
57 /* _usem flags */
58 #define SEM_NAMED 0x0002
59
60 /* op code for _umtx_op */
61 #define UMTX_OP_LOCK 0
62 #define UMTX_OP_UNLOCK 1
63 #define UMTX_OP_WAIT 2
64 #define UMTX_OP_WAKE 3
65 #define UMTX_OP_MUTEX_TRYLOCK 4
66 #define UMTX_OP_MUTEX_LOCK 5
67 #define UMTX_OP_MUTEX_UNLOCK 6
68 #define UMTX_OP_SET_CEILING 7
69 #define UMTX_OP_CV_WAIT 8
70 #define UMTX_OP_CV_SIGNAL 9
71 #define UMTX_OP_CV_BROADCAST 10
72 #define UMTX_OP_WAIT_UINT 11
73 #define UMTX_OP_RW_RDLOCK 12
74 #define UMTX_OP_RW_WRLOCK 13
75 #define UMTX_OP_RW_UNLOCK 14
76 #define UMTX_OP_WAIT_UINT_PRIVATE 15
77 #define UMTX_OP_WAKE_PRIVATE 16
78 #define UMTX_OP_MUTEX_WAIT 17
79 #define UMTX_OP_MUTEX_WAKE 18 /* deprecated */
80 #define UMTX_OP_SEM_WAIT 19
81 #define UMTX_OP_SEM_WAKE 20
82 #define UMTX_OP_NWAKE_PRIVATE 21
83 #define UMTX_OP_MUTEX_WAKE2 22
84 #define UMTX_OP_MAX 23
85
86 /* Flags for UMTX_OP_CV_WAIT */
87 #define CVWAIT_CHECK_UNPARKING 0x01
88 #define CVWAIT_ABSTIME 0x02
89 #define CVWAIT_CLOCKID 0x04
90
91 #define UMTX_CHECK_UNPARKING CVWAIT_CHECK_UNPARKING
92
93 #ifndef _KERNEL
94
95 int _umtx_op(void *obj, int op, u_long val, void *uaddr, void *uaddr2);
96
97 /*
98 * Old (deprecated) userland mutex system calls.
99 */
100 int _umtx_lock(struct umtx *mtx);
101 int _umtx_unlock(struct umtx *mtx);
102
103 /*
104 * Standard api. Try uncontested acquire/release and asks the
105 * kernel to resolve failures.
106 */
107 static __inline void
umtx_init(struct umtx * umtx)108 umtx_init(struct umtx *umtx)
109 {
110 umtx->u_owner = UMTX_UNOWNED;
111 }
112
113 static __inline u_long
umtx_owner(struct umtx * umtx)114 umtx_owner(struct umtx *umtx)
115 {
116 return (umtx->u_owner & ~LONG_MIN);
117 }
118
119 static __inline int
umtx_lock(struct umtx * umtx,u_long id)120 umtx_lock(struct umtx *umtx, u_long id)
121 {
122 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
123 if (_umtx_lock(umtx) == -1)
124 return (errno);
125 return (0);
126 }
127
128 static __inline int
umtx_trylock(struct umtx * umtx,u_long id)129 umtx_trylock(struct umtx *umtx, u_long id)
130 {
131 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
132 return (EBUSY);
133 return (0);
134 }
135
136 static __inline int
umtx_timedlock(struct umtx * umtx,u_long id,const struct timespec * timeout)137 umtx_timedlock(struct umtx *umtx, u_long id, const struct timespec *timeout)
138 {
139 if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
140 if (_umtx_op(umtx, UMTX_OP_LOCK, id, 0,
141 __DECONST(void *, timeout)) == -1)
142 return (errno);
143 return (0);
144 }
145
146 static __inline int
umtx_unlock(struct umtx * umtx,u_long id)147 umtx_unlock(struct umtx *umtx, u_long id)
148 {
149 if (atomic_cmpset_rel_long(&umtx->u_owner, id, UMTX_UNOWNED) == 0)
150 if (_umtx_unlock(umtx) == -1)
151 return (errno);
152 return (0);
153 }
154
155 static __inline int
umtx_wait(u_long * p,long val,const struct timespec * timeout)156 umtx_wait(u_long *p, long val, const struct timespec *timeout)
157 {
158 if (_umtx_op(p, UMTX_OP_WAIT, val, 0,
159 __DECONST(void *, timeout)) == -1)
160 return (errno);
161 return (0);
162 }
163
164 /* Wake threads waiting on a user address. */
165 static __inline int
umtx_wake(u_long * p,int nr_wakeup)166 umtx_wake(u_long *p, int nr_wakeup)
167 {
168 if (_umtx_op(p, UMTX_OP_WAKE, nr_wakeup, 0, 0) == -1)
169 return (errno);
170 return (0);
171 }
172
173 #else
174
175 /*
176 * The umtx_key structure is used by both the Linux futex code and the
177 * umtx implementation to map userland addresses to unique keys.
178 */
179
180 enum {
181 TYPE_SIMPLE_WAIT,
182 TYPE_CV,
183 TYPE_SEM,
184 TYPE_SIMPLE_LOCK,
185 TYPE_NORMAL_UMUTEX,
186 TYPE_PI_UMUTEX,
187 TYPE_PP_UMUTEX,
188 TYPE_RWLOCK,
189 TYPE_FUTEX
190 };
191
192 /* Key to represent a unique userland synchronous object */
193 struct umtx_key {
194 int hash;
195 int type;
196 int shared;
197 union {
198 struct {
199 struct vm_object *object;
200 uintptr_t offset;
201 } shared;
202 struct {
203 struct vmspace *vs;
204 uintptr_t addr;
205 } private;
206 struct {
207 void *a;
208 uintptr_t b;
209 } both;
210 } info;
211 };
212
213 #define THREAD_SHARE 0
214 #define PROCESS_SHARE 1
215 #define AUTO_SHARE 2
216
217 struct thread;
218
219 static inline int
umtx_key_match(const struct umtx_key * k1,const struct umtx_key * k2)220 umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2)
221 {
222 return (k1->type == k2->type &&
223 k1->info.both.a == k2->info.both.a &&
224 k1->info.both.b == k2->info.both.b);
225 }
226
227 int umtx_copyin_timeout(const void *, struct timespec *);
228 int umtx_key_get(void *, int, int, struct umtx_key *);
229 void umtx_key_release(struct umtx_key *);
230 struct umtx_q *umtxq_alloc(void);
231 void umtxq_free(struct umtx_q *);
232 int kern_umtx_wake(struct thread *, void *, int, int);
233 void umtx_pi_adjust(struct thread *, u_char);
234 void umtx_thread_init(struct thread *);
235 void umtx_thread_fini(struct thread *);
236 void umtx_thread_alloc(struct thread *);
237 void umtx_thread_exit(struct thread *);
238 #endif /* !_KERNEL */
239 #endif /* !_SYS_UMTX_H_ */
240