50  * Take the heavyweight lock.
52  * \param lock lock pointer.
54  * \return one if the lock is held, or zero otherwise.
56  * Attempt to mark the lock as held by the given context, via the \p cmpxchg instruction.
63 	volatile unsigned int *lock = &lock_data->hw_lock->lock;  in drm_lock_take()  local
67 		old = *lock;  in drm_lock_take()
75 		prev = cmpxchg(lock, old, new);  in drm_lock_take()
82 				DRM_ERROR("%d holds heavyweight lock\n",  in drm_lock_take()
90 		/* Have lock */  in drm_lock_take()
97  * This takes a lock forcibly and hands it to context.	Should ONLY be used
98  * inside *_unlock to give lock to kernel before calling *_dma_schedule.
101  * \param lock lock pointer.
105  * Resets the lock file pointer.
106  * Marks the lock as held by the given context, via the \p cmpxchg instruction.
112 	volatile unsigned int *lock = &lock_data->hw_lock->lock;  in drm_lock_transfer()  local
116 		old = *lock;  in drm_lock_transfer()
118 		prev = cmpxchg(lock, old, new);  in drm_lock_transfer()
127 	volatile unsigned int *lock = &lock_data->hw_lock->lock;  in drm_legacy_lock_free()  local
139 		old = *lock;  in drm_legacy_lock_free()
141 		prev = cmpxchg(lock, old, new);  in drm_legacy_lock_free()
145 		DRM_ERROR("%d freed heavyweight lock held by %d\n",  in drm_legacy_lock_free()
154  * Lock ioctl.
162  * Add the current task to the lock wait queue, and attempt to take to lock.
168 	struct drm_lock *lock = data;  in drm_legacy_lock()  local
177 	if (lock->context == DRM_KERNEL_CONTEXT) {  in drm_legacy_lock()
179 			  task_pid_nr(current), lock->context);  in drm_legacy_lock()
183 	DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",  in drm_legacy_lock()
184 		  lock->context, task_pid_nr(current),  in drm_legacy_lock()
185 		  master->lock.hw_lock ? master->lock.hw_lock->lock : -1,  in drm_legacy_lock()
186 		  lock->flags);  in drm_legacy_lock()
188 	add_wait_queue(&master->lock.lock_queue, &entry);  in drm_legacy_lock()
189 	spin_lock_bh(&master->lock.spinlock);  in drm_legacy_lock()
190 	master->lock.user_waiters++;  in drm_legacy_lock()
191 	spin_unlock_bh(&master->lock.spinlock);  in drm_legacy_lock()
195 		if (!master->lock.hw_lock) {  in drm_legacy_lock()
201 		if (drm_lock_take(&master->lock, lock->context)) {  in drm_legacy_lock()
202 			master->lock.file_priv = file_priv;  in drm_legacy_lock()
203 			master->lock.lock_time = jiffies;  in drm_legacy_lock()
204 			break;	/* Got lock */  in drm_legacy_lock()
216 	spin_lock_bh(&master->lock.spinlock);  in drm_legacy_lock()
217 	master->lock.user_waiters--;  in drm_legacy_lock()
218 	spin_unlock_bh(&master->lock.spinlock);  in drm_legacy_lock()
220 	remove_wait_queue(&master->lock.lock_queue, &entry);  in drm_legacy_lock()
222 	DRM_DEBUG("%d %s\n", lock->context,  in drm_legacy_lock()
223 		  ret ? "interrupted" : "has lock");  in drm_legacy_lock()
230 		dev->sigdata.context = lock->context;  in drm_legacy_lock()
231 		dev->sigdata.lock = master->lock.hw_lock;  in drm_legacy_lock()
234 	if (dev->driver->dma_quiescent && (lock->flags & _DRM_LOCK_QUIESCENT))  in drm_legacy_lock()
238 				  lock->context);  in drm_legacy_lock()
255  * Transfer and free the lock.
259 	struct drm_lock *lock = data;  in drm_legacy_unlock()  local
265 	if (lock->context == DRM_KERNEL_CONTEXT) {  in drm_legacy_unlock()
267 			  task_pid_nr(current), lock->context);  in drm_legacy_unlock()
271 	if (drm_legacy_lock_free(&master->lock, lock->context)) {  in drm_legacy_unlock()
279  * This function returns immediately and takes the hw lock
283  * This guarantees that the kernel will _eventually_ have the lock _unless_ it is held
284  * by a blocked process. (In the latter case an explicit wait for the hardware lock would cause
312 	volatile unsigned int *lock = &lock_data->hw_lock->lock;  in drm_legacy_idlelock_release()  local
318 				old = *lock;  in drm_legacy_idlelock_release()
319 				prev = cmpxchg(lock, old, DRM_KERNEL_CONTEXT);  in drm_legacy_idlelock_release()
334 	return (file_priv->lock_count && master->lock.hw_lock &&  in drm_legacy_i_have_hw_lock()
335 		_DRM_LOCK_IS_HELD(master->lock.hw_lock->lock) &&  in drm_legacy_i_have_hw_lock()
336 		master->lock.file_priv == file_priv);  in drm_legacy_i_have_hw_lock()
343 	/* if the master has gone away we can't do anything with the lock */  in drm_legacy_lock_release()
348 		DRM_DEBUG("File %p released, freeing lock for context %d\n",  in drm_legacy_lock_release()
349 			  filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));  in drm_legacy_lock_release()
350 		drm_legacy_lock_free(&file_priv->master->lock,  in drm_legacy_lock_release()
351 				     _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));  in drm_legacy_lock_release()
362 	 * possibility to lock.  in drm_legacy_lock_master_cleanup()
365 	if (master->lock.hw_lock) {  in drm_legacy_lock_master_cleanup()
366 		if (dev->sigdata.lock == master->lock.hw_lock)  in drm_legacy_lock_master_cleanup()
367 			dev->sigdata.lock = NULL;  in drm_legacy_lock_master_cleanup()
368 		master->lock.hw_lock = NULL;  in drm_legacy_lock_master_cleanup()
369 		master->lock.file_priv = NULL;  in drm_legacy_lock_master_cleanup()
370 		wake_up_interruptible_all(&master->lock.lock_queue);  in drm_legacy_lock_master_cleanup()