Input: uinput - use completions instead of events and manual (0048e603) · Commits · 戴 / test

drivers/input/misc/uinput.c

+43 −38

Original line number	Diff line number	Diff line
		@@ -53,24 +53,23 @@ static int uinput_dev_event(struct input_dev *dev, unsigned int type, unsigned i
		return 0;
		}

		static int uinput_request_alloc_id(struct input_dev dev, struct uinput_request request)
		static int uinput_request_alloc_id(struct uinput_device udev, struct uinput_request request)
		{
		/* Atomically allocate an ID for the given request. Returns 0 on success. */
		struct uinput_device *udev = dev->private;
		int id;
		int err = -1;

		down(&udev->requests_sem);
		spin_lock(&udev->requests_lock);

		for (id = 0; id < UINPUT_NUM_REQUESTS; id++)
		if (!udev->requests[id]) {
		udev->requests[id] = request;
		request->id = id;
		udev->requests[id] = request;
		err = 0;
		break;
		}

		up(&udev->requests_sem);
		spin_unlock(&udev->requests_lock);
		return err;
		}

		@@ -79,70 +78,78 @@ static struct uinput_request* uinput_request_find(struct uinput_device *udev, in
		/* Find an input request, by ID. Returns NULL if the ID isn't valid. */
		if (id >= UINPUT_NUM_REQUESTS \|\| id < 0)
		return NULL;
		if (udev->requests[id]->completed)
		return NULL;
		return udev->requests[id];
		}

		static void uinput_request_init(struct input_dev dev, struct uinput_request request, int code)
		static inline int uinput_request_reserve_slot(struct uinput_device udev, struct uinput_request request)
		{
		struct uinput_device *udev = dev->private;
		/* Allocate slot. If none are available right away, wait. */
		return wait_event_interruptible(udev->requests_waitq,
		!uinput_request_alloc_id(udev, request));
		}

		memset(request, 0, sizeof(struct uinput_request));
		request->code = code;
		init_waitqueue_head(&request->waitq);
		static void uinput_request_done(struct uinput_device udev, struct uinput_request request)
		{
		complete(&request->done);

		/* Allocate an ID. If none are available right away, wait. */
		request->retval = wait_event_interruptible(udev->requests_waitq,
		!uinput_request_alloc_id(dev, request));
		/* Mark slot as available */
		udev->requests[request->id] = NULL;
		wake_up_interruptible(&udev->requests_waitq);
		}

		static void uinput_request_submit(struct input_dev dev, struct uinput_request request)
		static int uinput_request_submit(struct input_dev dev, struct uinput_request request)
		{
		struct uinput_device *udev = dev->private;
		int retval;

		/* Tell our userspace app about this new request by queueing an input event */
		uinput_dev_event(dev, EV_UINPUT, request->code, request->id);

		/* Wait for the request to complete */
		retval = wait_event_interruptible(request->waitq, request->completed);
		if (retval)
		request->retval = retval;
		retval = wait_for_completion_interruptible(&request->done);
		if (!retval)
		retval = request->retval;

		/* Release this request's ID, let others know it's available */
		udev->requests[request->id] = NULL;
		wake_up_interruptible(&udev->requests_waitq);
		return retval;
		}

		static int uinput_dev_upload_effect(struct input_dev dev, struct ff_effect effect)
		{
		struct uinput_request request;
		int retval;

		if (!test_bit(EV_FF, dev->evbit))
		return -ENOSYS;

		uinput_request_init(dev, &request, UI_FF_UPLOAD);
		if (request.retval)
		return request.retval;
		request.id = -1;
		init_completion(&request.done);
		request.code = UI_FF_UPLOAD;
		request.u.effect = effect;
		uinput_request_submit(dev, &request);
		return request.retval;

		retval = uinput_request_reserve_slot(dev->private, &request);
		if (!retval)
		retval = uinput_request_submit(dev, &request);

		return retval;
		}

		static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
		{
		struct uinput_request request;
		int retval;

		if (!test_bit(EV_FF, dev->evbit))
		return -ENOSYS;

		uinput_request_init(dev, &request, UI_FF_ERASE);
		if (request.retval)
		return request.retval;
		request.id = -1;
		init_completion(&request.done);
		request.code = UI_FF_ERASE;
		request.u.effect_id = effect_id;
		uinput_request_submit(dev, &request);
		return request.retval;

		retval = uinput_request_reserve_slot(dev->private, &request);
		if (!retval)
		retval = uinput_request_submit(dev, &request);

		return retval;
		}

		static int uinput_create_device(struct uinput_device *udev)
		@@ -189,7 +196,7 @@ static int uinput_open(struct inode inode, struct file file)
		if (!newdev)
		goto error;
		memset(newdev, 0, sizeof(struct uinput_device));
		init_MUTEX(&newdev->requests_sem);
		spin_lock_init(&newdev->requests_lock);
		init_waitqueue_head(&newdev->requests_waitq);

		newinput = kmalloc(sizeof(struct input_dev), GFP_KERNEL);
		@@ -551,8 +558,7 @@ static int uinput_ioctl(struct inode inode, struct file file, unsigned int cmd
		}
		req->retval = ff_up.retval;
		memcpy(req->u.effect, &ff_up.effect, sizeof(struct ff_effect));
		req->completed = 1;
		wake_up_interruptible(&req->waitq);
		uinput_request_done(udev, req);
		break;

		case UI_END_FF_ERASE:
		@@ -566,8 +572,7 @@ static int uinput_ioctl(struct inode inode, struct file file, unsigned int cmd
		break;
		}
		req->retval = ff_erase.retval;
		req->completed = 1;
		wake_up_interruptible(&req->waitq);
		uinput_request_done(udev, req);
		break;

		default:

include/linux/uinput.h

+2 −3

Original line number	Diff line number	Diff line
		@@ -42,8 +42,7 @@ struct uinput_request {
		int code; /* UI_FF_UPLOAD, UI_FF_ERASE */

		int retval;
		wait_queue_head_t waitq;
		int completed;
		struct completion done;

		union {
		int effect_id;
		@@ -62,7 +61,7 @@ struct uinput_device {

		struct uinput_request *requests[UINPUT_NUM_REQUESTS];
		wait_queue_head_t requests_waitq;
		struct semaphore requests_sem;
		spinlock_t requests_lock;
		};
		#endif /* __KERNEL__ */

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