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 * $FreeBSD$
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_ABSTIME		0x01
92
93#define	UMTX_CHECK_UNPARKING	CVWAIT_CHECK_UNPARKING
94
95#ifndef _KERNEL
96
97int _umtx_op(void *obj, int op, u_long val, void *uaddr, void *uaddr2);
98
99/*
100 * Old (deprecated) userland mutex system calls.
101 */
102int _umtx_lock(struct umtx *mtx);
103int _umtx_unlock(struct umtx *mtx);
104
105/*
106 * Standard api.  Try uncontested acquire/release and asks the
107 * kernel to resolve failures.
108 */
109static __inline void
110umtx_init(struct umtx *umtx)
111{
112	umtx->u_owner = UMTX_UNOWNED;
113}
114
115static __inline u_long
116umtx_owner(struct umtx *umtx)
117{
118	return (umtx->u_owner & ~LONG_MIN);
119}
120
121static __inline int
122umtx_lock(struct umtx *umtx, u_long id)
123{
124	if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
125		if (_umtx_lock(umtx) == -1)
126			return (errno);
127	return (0);
128}
129
130static __inline int
131umtx_trylock(struct umtx *umtx, u_long id)
132{
133	if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
134		return (EBUSY);
135	return (0);
136}
137
138static __inline int
139umtx_timedlock(struct umtx *umtx, u_long id, const struct timespec *timeout)
140{
141	if (atomic_cmpset_acq_long(&umtx->u_owner, UMTX_UNOWNED, id) == 0)
142		if (_umtx_op(umtx, UMTX_OP_LOCK, id, 0,
143		    __DECONST(void *, timeout)) == -1)
144			return (errno);
145	return (0);
146}
147
148static __inline int
149umtx_unlock(struct umtx *umtx, u_long id)
150{
151	if (atomic_cmpset_rel_long(&umtx->u_owner, id, UMTX_UNOWNED) == 0)
152		if (_umtx_unlock(umtx) == -1)
153			return (errno);
154	return (0);
155}
156
157static __inline int
158umtx_wait(u_long *p, long val, const struct timespec *timeout)
159{
160	if (_umtx_op(p, UMTX_OP_WAIT, val, 0,
161	    __DECONST(void *, timeout)) == -1)
162		return (errno);
163	return (0);
164}
165
166/* Wake threads waiting on a user address. */
167static __inline int
168umtx_wake(u_long *p, int nr_wakeup)
169{
170	if (_umtx_op(p, UMTX_OP_WAKE, nr_wakeup, 0, 0) == -1)
171		return (errno);
172	return (0);
173}
174
175#else
176
177/*
178 * The umtx_key structure is used by both the Linux futex code and the
179 * umtx implementation to map userland addresses to unique keys.
180 */
181
182enum {
183	TYPE_SIMPLE_WAIT,
184	TYPE_CV,
185	TYPE_SEM,
186	TYPE_SIMPLE_LOCK,
187	TYPE_NORMAL_UMUTEX,
188	TYPE_PI_UMUTEX,
189	TYPE_PP_UMUTEX,
190	TYPE_RWLOCK,
191	TYPE_FUTEX
192};
193
194/* Key to represent a unique userland synchronous object */
195struct umtx_key {
196	int	hash;
197	int	type;
198	int	shared;
199	union {
200		struct {
201			struct vm_object *object;
202			uintptr_t	offset;
203		} shared;
204		struct {
205			struct vmspace	*vs;
206			uintptr_t	addr;
207		} private;
208		struct {
209			void		*a;
210			uintptr_t	b;
211		} both;
212	} info;
213};
214
215#define THREAD_SHARE		0
216#define PROCESS_SHARE		1
217#define AUTO_SHARE		2
218
219struct thread;
220
221static inline int
222umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2)
223{
224	return (k1->type == k2->type &&
225		k1->info.both.a == k2->info.both.a &&
226	        k1->info.both.b == k2->info.both.b);
227}
228
229int umtx_copyin_timeout(const void *, struct timespec *);
230int umtx_key_get(void *, int, int, struct umtx_key *);
231void umtx_key_release(struct umtx_key *);
232struct umtx_q *umtxq_alloc(void);
233void umtxq_free(struct umtx_q *);
234int kern_umtx_wake(struct thread *, void *, int, int);
235void umtx_pi_adjust(struct thread *, u_char);
236void umtx_thread_init(struct thread *);
237void umtx_thread_fini(struct thread *);
238void umtx_thread_alloc(struct thread *);
239void umtx_thread_exit(struct thread *);
240#endif /* !_KERNEL */
241#endif /* !_SYS_UMTX_H_ */
242