Commit 0ebeaab4 authored by Kent Gibson's avatar Kent Gibson Committed by Bartosz Golaszewski
Browse files

gpiolib: cdev: fully adopt guard() and scoped_guard() 



Use guard() or scoped_guard() for critical sections rather than
discrete lock/unlock pairs.

Signed-off-by: default avatarKent Gibson <warthog618@gmail.com>
Reviewed-by: default avatarAndy Shevchenko <andy@kernel.org>
Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent d8543cba

drivers/gpio/gpiolib-cdev.c

+57 −86
Original line number Diff line number Diff line
@@ -748,13 +748,13 @@ static void linereq_put_event(struct linereq *lr, 
{

	bool overflow = false;



	spin_lock(&lr->wait.lock);

	scoped_guard(spinlock, &lr->wait.lock) {

		if (kfifo_is_full(&lr->events)) {

			overflow = true;

			kfifo_skip(&lr->events);

		}

		kfifo_in(&lr->events, le, 1);

	spin_unlock(&lr->wait.lock);

	}

	if (!overflow)

		wake_up_poll(&lr->wait, EPOLLIN);

	else
@@ -1487,18 +1487,13 @@ static long linereq_set_values_unlocked(struct linereq *lr, 
static long linereq_set_values(struct linereq *lr, void __user *ip)

{

	struct gpio_v2_line_values lv;

	int ret;



	if (copy_from_user(&lv, ip, sizeof(lv)))

		return -EFAULT;



	mutex_lock(&lr->config_mutex);



	ret = linereq_set_values_unlocked(lr, &lv);



	mutex_unlock(&lr->config_mutex);

	guard(mutex)(&lr->config_mutex);



	return ret;

	return linereq_set_values_unlocked(lr, &lv);

}



static long linereq_set_config_unlocked(struct linereq *lr,
@@ -1556,13 +1551,9 @@ static long linereq_set_config(struct linereq *lr, void __user *ip) 
	if (ret)

		return ret;



	mutex_lock(&lr->config_mutex);



	ret = linereq_set_config_unlocked(lr, &lc);



	mutex_unlock(&lr->config_mutex);

	guard(mutex)(&lr->config_mutex);



	return ret;

	return linereq_set_config_unlocked(lr, &lc);

}



static long linereq_ioctl_unlocked(struct file *file, unsigned int cmd,
@@ -1644,28 +1635,22 @@ static ssize_t linereq_read_unlocked(struct file *file, char __user *buf, 
		return -EINVAL;



	do {

		spin_lock(&lr->wait.lock);

		scoped_guard(spinlock, &lr->wait.lock) {

			if (kfifo_is_empty(&lr->events)) {

			if (bytes_read) {

				spin_unlock(&lr->wait.lock);

				if (bytes_read)

					return bytes_read;

			}



			if (file->f_flags & O_NONBLOCK) {

				spin_unlock(&lr->wait.lock);

				if (file->f_flags & O_NONBLOCK)

					return -EAGAIN;

			}



				ret = wait_event_interruptible_locked(lr->wait,

						!kfifo_is_empty(&lr->events));

			if (ret) {

				spin_unlock(&lr->wait.lock);

				if (ret)

					return ret;

			}

		}



			ret = kfifo_out(&lr->events, &le, 1);

		spin_unlock(&lr->wait.lock);

		}

		if (ret != 1) {

			/*

			 * This should never happen - we were holding the
@@ -2015,28 +2000,22 @@ static ssize_t lineevent_read_unlocked(struct file *file, char __user *buf, 
		return -EINVAL;



	do {

		spin_lock(&le->wait.lock);

		scoped_guard(spinlock, &le->wait.lock) {

			if (kfifo_is_empty(&le->events)) {

			if (bytes_read) {

				spin_unlock(&le->wait.lock);

				if (bytes_read)

					return bytes_read;

			}



			if (file->f_flags & O_NONBLOCK) {

				spin_unlock(&le->wait.lock);

				if (file->f_flags & O_NONBLOCK)

					return -EAGAIN;

			}



				ret = wait_event_interruptible_locked(le->wait,

						!kfifo_is_empty(&le->events));

			if (ret) {

				spin_unlock(&le->wait.lock);

				if (ret)

					return ret;

			}

		}



			ret = kfifo_out(&le->events, &ge, 1);

		spin_unlock(&le->wait.lock);

		}

		if (ret != 1) {

			/*

			 * This should never happen - we were holding the lock
@@ -2732,38 +2711,30 @@ static ssize_t lineinfo_watch_read_unlocked(struct file *file, char __user *buf, 
#endif



	do {

		spin_lock(&cdev->wait.lock);

		scoped_guard(spinlock, &cdev->wait.lock) {

			if (kfifo_is_empty(&cdev->events)) {

			if (bytes_read) {

				spin_unlock(&cdev->wait.lock);

				if (bytes_read)

					return bytes_read;

			}



			if (file->f_flags & O_NONBLOCK) {

				spin_unlock(&cdev->wait.lock);

				if (file->f_flags & O_NONBLOCK)

					return -EAGAIN;

			}



				ret = wait_event_interruptible_locked(cdev->wait,

						!kfifo_is_empty(&cdev->events));

			if (ret) {

				spin_unlock(&cdev->wait.lock);

				if (ret)

					return ret;

			}

		}

#ifdef CONFIG_GPIO_CDEV_V1

			/* must be after kfifo check so watch_abi_version is set */

			if (atomic_read(&cdev->watch_abi_version) == 2)

				event_size = sizeof(struct gpio_v2_line_info_changed);

			else

				event_size = sizeof(struct gpioline_info_changed);

		if (count < event_size) {

			spin_unlock(&cdev->wait.lock);

			if (count < event_size)

				return -EINVAL;

		}

#endif

			ret = kfifo_out(&cdev->events, &event, 1);

		spin_unlock(&cdev->wait.lock);

		}

		if (ret != 1) {

			ret = -EIO;

			break;