1 /* SPDX-License-Identifier: GPL-2.0 */
35 #define ww_mutex_base_is_locked(b)	rt_mutex_base_is_locked(&(b)->rtmutex)
88  * ww_mutex_init - initialize the w/w mutex
96  * It is not allowed to initialize an already locked mutex.
101 	ww_mutex_base_init(&lock->base, ww_class->mutex_name, &ww_class->mutex_key);  in ww_mutex_init()
102 	lock->ctx = NULL;  in ww_mutex_init()
104 	lock->ww_class = ww_class;  in ww_mutex_init()
109  * ww_acquire_init - initialize a w/w acquire context
115  * Context-based w/w mutex acquiring can be done in any order whatsoever within
119  * Mixing of context-based w/w mutex acquiring and single w/w mutex locking can
135 	ctx->task = current;  in ww_acquire_init()
136 	ctx->stamp = atomic_long_inc_return_relaxed(&ww_class->stamp);  in ww_acquire_init()
137 	ctx->acquired = 0;  in ww_acquire_init()
138 	ctx->wounded = false;  in ww_acquire_init()
139 	ctx->is_wait_die = ww_class->is_wait_die;  in ww_acquire_init()
141 	ctx->ww_class = ww_class;  in ww_acquire_init()
142 	ctx->done_acquire = 0;  in ww_acquire_init()
143 	ctx->contending_lock = NULL;  in ww_acquire_init()
147 	lockdep_init_map(&ctx->dep_map, ww_class->acquire_name,  in ww_acquire_init()
148 			 &ww_class->acquire_key, 0);  in ww_acquire_init()
149 	mutex_acquire(&ctx->dep_map, 0, 0, _RET_IP_);  in ww_acquire_init()
152 	ctx->deadlock_inject_interval = 1;  in ww_acquire_init()
153 	ctx->deadlock_inject_countdown = ctx->stamp & 0xf;  in ww_acquire_init()
158  * ww_acquire_done - marks the end of the acquire phase
161  * Marks the end of the acquire phase, any further w/w mutex lock calls using
165  * code and clearly designated the acquire phase from actually using the locked
173 	DEBUG_LOCKS_WARN_ON(ctx->done_acquire);  in ww_acquire_done()
174 	ctx->done_acquire = 1;  in ww_acquire_done()
179  * ww_acquire_fini - releases a w/w acquire context
188 	mutex_release(&ctx->dep_map, _THIS_IP_);  in ww_acquire_fini()
191 	DEBUG_LOCKS_WARN_ON(ctx->acquired);  in ww_acquire_fini()
197 		ctx->done_acquire = 1;  in ww_acquire_fini()
201 		ctx->acquired = ~0U;  in ww_acquire_fini()
206  * ww_mutex_lock - acquire the w/w mutex
215  * for backing off by returning -EDEADLK (die case). Trying to acquire the
217  * returning -EALREADY. Returns 0 if the mutex was successfully acquired.
228  * locked. The mutex must first be initialized (or statically defined) before it
229  * can be locked. memset()-ing the mutex to 0 is not allowed. The mutex must be
237  * ww_mutex_lock_interruptible - acquire the w/w mutex, interruptible
246  * for backing off by returning -EDEADLK (die case). Trying to acquire the
248  * returning -EALREADY. Returns 0 if the mutex was successfully acquired. If a
249  * signal arrives while waiting for the lock then this function returns -EINTR.
260  * locked. The mutex must first be initialized (or statically defined) before it
261  * can be locked. memset()-ing the mutex to 0 is not allowed. The mutex must be
270  * ww_mutex_lock_slow - slowpath acquiring of the w/w mutex
281  * needs with ww_mutex_lock. Note that the -EALREADY return code from
297 	DEBUG_LOCKS_WARN_ON(!ctx->contending_lock);  in ww_mutex_lock_slow()
304  * ww_mutex_lock_slow_interruptible - slowpath acquiring of the w/w mutex, interruptible
311  * function returns -EINTR.
317  * needs with ww_mutex_lock. Note that the -EALREADY return code from
333 	DEBUG_LOCKS_WARN_ON(!ctx->contending_lock);  in ww_mutex_lock_slow_interruptible()
344  * ww_mutex_destroy - mark a w/w mutex unusable
348  * use of the mutex is forbidden. The mutex must not be locked when
354 	mutex_destroy(&lock->base);  in ww_mutex_destroy()
359  * ww_mutex_is_locked - is the w/w mutex locked
362  * Returns 1 if the mutex is locked, 0 if unlocked.
366 	return ww_mutex_base_is_locked(&lock->base);  in ww_mutex_is_locked()