drm2/ttm/ttm_lock.c

50 void ttm_lock_init(struct ttm_lock *lock)
52 	mtx_init(&lock->lock, "ttmlk", NULL, MTX_DEF);
53 	lock->rw = 0;
54 	lock->flags = 0;
55 	lock->kill_takers = false;
56 	lock->signal = SIGKILL;
70 void ttm_read_unlock(struct ttm_lock *lock)
72 	mtx_lock(&lock->lock);
73 	if (--lock->rw == 0)
74 		wakeup(lock);
75 	mtx_unlock(&lock->lock);
78 static bool __ttm_read_lock(struct ttm_lock *lock)
82 	if (unlikely(lock->kill_takers)) {
83 		ttm_lock_send_sig(lock->signal);
86 	if (lock->rw >= 0 && lock->flags == 0) {
87 		++lock->rw;
94 ttm_read_lock(struct ttm_lock *lock, bool interruptible)
107 	mtx_lock(&lock->lock);
108 	while (!__ttm_read_lock(lock)) {
109 		ret = msleep(lock, &lock->lock, flags, wmsg, 0);
118 static bool __ttm_read_trylock(struct ttm_lock *lock, bool *locked)
124 	if (unlikely(lock->kill_takers)) {
125 		ttm_lock_send_sig(lock->signal);
128 	if (lock->rw >= 0 && lock->flags == 0) {
129 		++lock->rw;
132 	} else if (lock->flags == 0) {
139 int ttm_read_trylock(struct ttm_lock *lock, bool interruptible)
153 	mtx_lock(&lock->lock);
154 	while (!__ttm_read_trylock(lock, &locked)) {
155 		ret = msleep(lock, &lock->lock, flags, wmsg, 0);
162 	mtx_unlock(&lock->lock);
167 void ttm_write_unlock(struct ttm_lock *lock)
169 	mtx_lock(&lock->lock);
170 	lock->rw = 0;
171 	wakeup(lock);
172 	mtx_unlock(&lock->lock);
175 static bool __ttm_write_lock(struct ttm_lock *lock)
179 	if (unlikely(lock->kill_takers)) {
180 		ttm_lock_send_sig(lock->signal);
183 	if (lock->rw == 0 && ((lock->flags & ~TTM_WRITE_LOCK_PENDING) == 0)) {
184 		lock->rw = -1;
185 		lock->flags &= ~TTM_WRITE_LOCK_PENDING;
188 		lock->flags |= TTM_WRITE_LOCK_PENDING;
194 ttm_write_lock(struct ttm_lock *lock, bool interruptible)
207 	mtx_lock(&lock->lock);
209 	while (!__ttm_write_lock(lock)) {
210 		ret = msleep(lock, &lock->lock, flags, wmsg, 0);
214 			lock->flags &= ~TTM_WRITE_LOCK_PENDING;
215 			wakeup(lock);
219 	mtx_unlock(&lock->lock);
224 void ttm_write_lock_downgrade(struct ttm_lock *lock)
226 	mtx_lock(&lock->lock);
227 	lock->rw = 1;
228 	wakeup(lock);
229 	mtx_unlock(&lock->lock);
232 static int __ttm_vt_unlock(struct ttm_lock *lock)
236 	mtx_lock(&lock->lock);
237 	if (unlikely(!(lock->flags & TTM_VT_LOCK)))
239 	lock->flags &= ~TTM_VT_LOCK;
240 	wakeup(lock);
241 	mtx_unlock(&lock->lock);
249 	struct ttm_lock *lock = container_of(base, struct ttm_lock, base);
253 	ret = __ttm_vt_unlock(lock);
257 static bool __ttm_vt_lock(struct ttm_lock *lock)
261 	if (lock->rw == 0) {
262 		lock->flags &= ~TTM_VT_LOCK_PENDING;
263 		lock->flags |= TTM_VT_LOCK;
266 		lock->flags |= TTM_VT_LOCK_PENDING;
271 int ttm_vt_lock(struct ttm_lock *lock,
286 	mtx_lock(&lock->lock);
287 	while (!__ttm_vt_lock(lock)) {
288 		ret = msleep(lock, &lock->lock, flags, wmsg, 0);
292 			lock->flags &= ~TTM_VT_LOCK_PENDING;
293 			wakeup(lock);
300 	 * make sure the lock is released if the client dies
304 	ret = ttm_base_object_init(tfile, &lock->base, false,
307 		(void)__ttm_vt_unlock(lock);
309 		lock->vt_holder = tfile;
314 int ttm_vt_unlock(struct ttm_lock *lock)
316 	return ttm_ref_object_base_unref(lock->vt_holder,
317 					 lock->base.hash.key, TTM_REF_USAGE);
320 void ttm_suspend_unlock(struct ttm_lock *lock)
322 	mtx_lock(&lock->lock);
323 	lock->flags &= ~TTM_SUSPEND_LOCK;
324 	wakeup(lock);
325 	mtx_unlock(&lock->lock);
328 static bool __ttm_suspend_lock(struct ttm_lock *lock)
332 	if (lock->rw == 0) {
333 		lock->flags &= ~TTM_SUSPEND_LOCK_PENDING;
334 		lock->flags |= TTM_SUSPEND_LOCK;
337 		lock->flags |= TTM_SUSPEND_LOCK_PENDING;
342 void ttm_suspend_lock(struct ttm_lock *lock)
344 	mtx_lock(&lock->lock);
345 	while (!__ttm_suspend_lock(lock))
346 		msleep(lock, &lock->lock, 0, "ttms", 0);
347 	mtx_unlock(&lock->lock);