1 #ifndef __LINUX_RWLOCK_API_SMP_H
2 #define __LINUX_RWLOCK_API_SMP_H
3 
4 #ifndef __LINUX_SPINLOCK_API_SMP_H
5 # error "please don't include this file directly"
6 #endif
7 
8 /*
9  * include/linux/rwlock_api_smp.h
10  *
11  * spinlock API declarations on SMP (and debug)
12  * (implemented in kernel/spinlock.c)
13  *
14  * portions Copyright 2005, Red Hat, Inc., Ingo Molnar
15  * Released under the General Public License (GPL).
16  */
17 
18 void __lockfunc _raw_read_lock(rwlock_t *lock)		__acquires(lock);
19 void __lockfunc _raw_write_lock(rwlock_t *lock)		__acquires(lock);
20 void __lockfunc _raw_write_lock_nested(rwlock_t *lock, int subclass)	__acquires(lock);
21 void __lockfunc _raw_read_lock_bh(rwlock_t *lock)	__acquires(lock);
22 void __lockfunc _raw_write_lock_bh(rwlock_t *lock)	__acquires(lock);
23 void __lockfunc _raw_read_lock_irq(rwlock_t *lock)	__acquires(lock);
24 void __lockfunc _raw_write_lock_irq(rwlock_t *lock)	__acquires(lock);
25 unsigned long __lockfunc _raw_read_lock_irqsave(rwlock_t *lock)
26 							__acquires(lock);
27 unsigned long __lockfunc _raw_write_lock_irqsave(rwlock_t *lock)
28 							__acquires(lock);
29 int __lockfunc _raw_read_trylock(rwlock_t *lock);
30 int __lockfunc _raw_write_trylock(rwlock_t *lock);
31 void __lockfunc _raw_read_unlock(rwlock_t *lock)	__releases(lock);
32 void __lockfunc _raw_write_unlock(rwlock_t *lock)	__releases(lock);
33 void __lockfunc _raw_read_unlock_bh(rwlock_t *lock)	__releases(lock);
34 void __lockfunc _raw_write_unlock_bh(rwlock_t *lock)	__releases(lock);
35 void __lockfunc _raw_read_unlock_irq(rwlock_t *lock)	__releases(lock);
36 void __lockfunc _raw_write_unlock_irq(rwlock_t *lock)	__releases(lock);
37 void __lockfunc
38 _raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
39 							__releases(lock);
40 void __lockfunc
41 _raw_write_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
42 							__releases(lock);
43 
44 #ifdef CONFIG_INLINE_READ_LOCK
45 #define _raw_read_lock(lock) __raw_read_lock(lock)
46 #endif
47 
48 #ifdef CONFIG_INLINE_WRITE_LOCK
49 #define _raw_write_lock(lock) __raw_write_lock(lock)
50 #endif
51 
52 #ifdef CONFIG_INLINE_READ_LOCK_BH
53 #define _raw_read_lock_bh(lock) __raw_read_lock_bh(lock)
54 #endif
55 
56 #ifdef CONFIG_INLINE_WRITE_LOCK_BH
57 #define _raw_write_lock_bh(lock) __raw_write_lock_bh(lock)
58 #endif
59 
60 #ifdef CONFIG_INLINE_READ_LOCK_IRQ
61 #define _raw_read_lock_irq(lock) __raw_read_lock_irq(lock)
62 #endif
63 
64 #ifdef CONFIG_INLINE_WRITE_LOCK_IRQ
65 #define _raw_write_lock_irq(lock) __raw_write_lock_irq(lock)
66 #endif
67 
68 #ifdef CONFIG_INLINE_READ_LOCK_IRQSAVE
69 #define _raw_read_lock_irqsave(lock) __raw_read_lock_irqsave(lock)
70 #endif
71 
72 #ifdef CONFIG_INLINE_WRITE_LOCK_IRQSAVE
73 #define _raw_write_lock_irqsave(lock) __raw_write_lock_irqsave(lock)
74 #endif
75 
76 #ifdef CONFIG_INLINE_READ_TRYLOCK
77 #define _raw_read_trylock(lock) __raw_read_trylock(lock)
78 #endif
79 
80 #ifdef CONFIG_INLINE_WRITE_TRYLOCK
81 #define _raw_write_trylock(lock) __raw_write_trylock(lock)
82 #endif
83 
84 #ifdef CONFIG_INLINE_READ_UNLOCK
85 #define _raw_read_unlock(lock) __raw_read_unlock(lock)
86 #endif
87 
88 #ifdef CONFIG_INLINE_WRITE_UNLOCK
89 #define _raw_write_unlock(lock) __raw_write_unlock(lock)
90 #endif
91 
92 #ifdef CONFIG_INLINE_READ_UNLOCK_BH
93 #define _raw_read_unlock_bh(lock) __raw_read_unlock_bh(lock)
94 #endif
95 
96 #ifdef CONFIG_INLINE_WRITE_UNLOCK_BH
97 #define _raw_write_unlock_bh(lock) __raw_write_unlock_bh(lock)
98 #endif
99 
100 #ifdef CONFIG_INLINE_READ_UNLOCK_IRQ
101 #define _raw_read_unlock_irq(lock) __raw_read_unlock_irq(lock)
102 #endif
103 
104 #ifdef CONFIG_INLINE_WRITE_UNLOCK_IRQ
105 #define _raw_write_unlock_irq(lock) __raw_write_unlock_irq(lock)
106 #endif
107 
108 #ifdef CONFIG_INLINE_READ_UNLOCK_IRQRESTORE
109 #define _raw_read_unlock_irqrestore(lock, flags) \
110 	__raw_read_unlock_irqrestore(lock, flags)
111 #endif
112 
113 #ifdef CONFIG_INLINE_WRITE_UNLOCK_IRQRESTORE
114 #define _raw_write_unlock_irqrestore(lock, flags) \
115 	__raw_write_unlock_irqrestore(lock, flags)
116 #endif
117 
118 static inline int __raw_read_trylock(rwlock_t *lock)
119 {
120 	preempt_disable();
121 	if (do_raw_read_trylock(lock)) {
122 		rwlock_acquire_read(&lock->dep_map, 0, 1, _RET_IP_);
123 		return 1;
124 	}
125 	preempt_enable();
126 	return 0;
127 }
128 
129 static inline int __raw_write_trylock(rwlock_t *lock)
130 {
131 	preempt_disable();
132 	if (do_raw_write_trylock(lock)) {
133 		rwlock_acquire(&lock->dep_map, 0, 1, _RET_IP_);
134 		return 1;
135 	}
136 	preempt_enable();
137 	return 0;
138 }
139 
140 /*
141  * If lockdep is enabled then we use the non-preemption spin-ops
142  * even on CONFIG_PREEMPT, because lockdep assumes that interrupts are
143  * not re-enabled during lock-acquire (which the preempt-spin-ops do):
144  */
145 #if !defined(CONFIG_GENERIC_LOCKBREAK) || defined(CONFIG_DEBUG_LOCK_ALLOC)
146 
147 static inline void __raw_read_lock(rwlock_t *lock)
148 {
149 	preempt_disable();
150 	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
151 	LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
152 }
153 
154 static inline unsigned long __raw_read_lock_irqsave(rwlock_t *lock)
155 {
156 	unsigned long flags;
157 
158 	local_irq_save(flags);
159 	preempt_disable();
160 	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
161 	LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
162 	return flags;
163 }
164 
165 static inline void __raw_read_lock_irq(rwlock_t *lock)
166 {
167 	local_irq_disable();
168 	preempt_disable();
169 	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
170 	LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
171 }
172 
173 static inline void __raw_read_lock_bh(rwlock_t *lock)
174 {
175 	__local_bh_disable_ip(_RET_IP_, SOFTIRQ_LOCK_OFFSET);
176 	rwlock_acquire_read(&lock->dep_map, 0, 0, _RET_IP_);
177 	LOCK_CONTENDED(lock, do_raw_read_trylock, do_raw_read_lock);
178 }
179 
180 static inline unsigned long __raw_write_lock_irqsave(rwlock_t *lock)
181 {
182 	unsigned long flags;
183 
184 	local_irq_save(flags);
185 	preempt_disable();
186 	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
187 	LOCK_CONTENDED(lock, do_raw_write_trylock, do_raw_write_lock);
188 	return flags;
189 }
190 
191 static inline void __raw_write_lock_irq(rwlock_t *lock)
192 {
193 	local_irq_disable();
194 	preempt_disable();
195 	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
196 	LOCK_CONTENDED(lock, do_raw_write_trylock, do_raw_write_lock);
197 }
198 
199 static inline void __raw_write_lock_bh(rwlock_t *lock)
200 {
201 	__local_bh_disable_ip(_RET_IP_, SOFTIRQ_LOCK_OFFSET);
202 	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
203 	LOCK_CONTENDED(lock, do_raw_write_trylock, do_raw_write_lock);
204 }
205 
206 static inline void __raw_write_lock(rwlock_t *lock)
207 {
208 	preempt_disable();
209 	rwlock_acquire(&lock->dep_map, 0, 0, _RET_IP_);
210 	LOCK_CONTENDED(lock, do_raw_write_trylock, do_raw_write_lock);
211 }
212 
213 static inline void __raw_write_lock_nested(rwlock_t *lock, int subclass)
214 {
215 	preempt_disable();
216 	rwlock_acquire(&lock->dep_map, subclass, 0, _RET_IP_);
217 	LOCK_CONTENDED(lock, do_raw_write_trylock, do_raw_write_lock);
218 }
219 
220 #endif /* !CONFIG_GENERIC_LOCKBREAK || CONFIG_DEBUG_LOCK_ALLOC */
221 
222 static inline void __raw_write_unlock(rwlock_t *lock)
223 {
224 	rwlock_release(&lock->dep_map, _RET_IP_);
225 	do_raw_write_unlock(lock);
226 	preempt_enable();
227 }
228 
229 static inline void __raw_read_unlock(rwlock_t *lock)
230 {
231 	rwlock_release(&lock->dep_map, _RET_IP_);
232 	do_raw_read_unlock(lock);
233 	preempt_enable();
234 }
235 
236 static inline void
237 __raw_read_unlock_irqrestore(rwlock_t *lock, unsigned long flags)
238 {
239 	rwlock_release(&lock->dep_map, _RET_IP_);
240 	do_raw_read_unlock(lock);
241 	local_irq_restore(flags);
242 	preempt_enable();
243 }
244 
245 static inline void __raw_read_unlock_irq(rwlock_t *lock)
246 {
247 	rwlock_release(&lock->dep_map, _RET_IP_);
248 	do_raw_read_unlock(lock);
249 	local_irq_enable();
250 	preempt_enable();
251 }
252 
253 static inline void __raw_read_unlock_bh(rwlock_t *lock)
254 {
255 	rwlock_release(&lock->dep_map, _RET_IP_);
256 	do_raw_read_unlock(lock);
257 	__local_bh_enable_ip(_RET_IP_, SOFTIRQ_LOCK_OFFSET);
258 }
259 
260 static inline void __raw_write_unlock_irqrestore(rwlock_t *lock,
261 					     unsigned long flags)
262 {
263 	rwlock_release(&lock->dep_map, _RET_IP_);
264 	do_raw_write_unlock(lock);
265 	local_irq_restore(flags);
266 	preempt_enable();
267 }
268 
269 static inline void __raw_write_unlock_irq(rwlock_t *lock)
270 {
271 	rwlock_release(&lock->dep_map, _RET_IP_);
272 	do_raw_write_unlock(lock);
273 	local_irq_enable();
274 	preempt_enable();
275 }
276 
277 static inline void __raw_write_unlock_bh(rwlock_t *lock)
278 {
279 	rwlock_release(&lock->dep_map, _RET_IP_);
280 	do_raw_write_unlock(lock);
281 	__local_bh_enable_ip(_RET_IP_, SOFTIRQ_LOCK_OFFSET);
282 }
283 
284 #endif /* __LINUX_RWLOCK_API_SMP_H */
285