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

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

Signed-off-by: Kent Gibson <warthog618@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
This commit is contained in:
Kent Gibson 2023-12-19 08:41:57 +08:00 committed by Bartosz Golaszewski
parent d8543cbaf9
commit 0ebeaab4d5
1 changed files with 55 additions and 84 deletions
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139
drivers/gpio/gpiolib-cdev.c
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@ -748,13 +748,13 @@ static void linereq_put_event(struct linereq *lr,
{
bool overflow = false;
spin_lock(&lr->wait.lock);
if (kfifo_is_full(&lr->events)) {
overflow = true;
kfifo_skip(&lr->events);
scoped_guard(spinlock, &lr->wait.lock) {
if (kfifo_is_full(&lr->events)) {
overflow = true;
kfifo_skip(&lr->events);
}
kfifo_in(&lr->events, le, 1);
}
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);
guard(mutex)(&lr->config_mutex);
ret = linereq_set_values_unlocked(lr, &lv);
mutex_unlock(&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);
guard(mutex)(&lr->config_mutex);
ret = linereq_set_config_unlocked(lr, &lc);
mutex_unlock(&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);
if (kfifo_is_empty(&lr->events)) {
if (bytes_read) {
spin_unlock(&lr->wait.lock);
return bytes_read;
scoped_guard(spinlock, &lr->wait.lock) {
if (kfifo_is_empty(&lr->events)) {
if (bytes_read)
return bytes_read;
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible_locked(lr->wait,
!kfifo_is_empty(&lr->events));
if (ret)
return ret;
}
if (file->f_flags & O_NONBLOCK) {
spin_unlock(&lr->wait.lock);
return -EAGAIN;
}
ret = wait_event_interruptible_locked(lr->wait,
!kfifo_is_empty(&lr->events));
if (ret) {
spin_unlock(&lr->wait.lock);
return ret;
}
ret = kfifo_out(&lr->events, &le, 1);
}
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);
if (kfifo_is_empty(&le->events)) {
if (bytes_read) {
spin_unlock(&le->wait.lock);
return bytes_read;
scoped_guard(spinlock, &le->wait.lock) {
if (kfifo_is_empty(&le->events)) {
if (bytes_read)
return bytes_read;
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible_locked(le->wait,
!kfifo_is_empty(&le->events));
if (ret)
return ret;
}
if (file->f_flags & O_NONBLOCK) {
spin_unlock(&le->wait.lock);
return -EAGAIN;
}
ret = wait_event_interruptible_locked(le->wait,
!kfifo_is_empty(&le->events));
if (ret) {
spin_unlock(&le->wait.lock);
return ret;
}
ret = kfifo_out(&le->events, &ge, 1);
}
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);
if (kfifo_is_empty(&cdev->events)) {
if (bytes_read) {
spin_unlock(&cdev->wait.lock);
return bytes_read;
}
scoped_guard(spinlock, &cdev->wait.lock) {
if (kfifo_is_empty(&cdev->events)) {
if (bytes_read)
return bytes_read;
if (file->f_flags & O_NONBLOCK) {
spin_unlock(&cdev->wait.lock);
return -EAGAIN;
}
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);
return ret;
ret = wait_event_interruptible_locked(cdev->wait,
!kfifo_is_empty(&cdev->events));
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);
return -EINVAL;
}
/* 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)
return -EINVAL;
#endif
ret = kfifo_out(&cdev->events, &event, 1);
spin_unlock(&cdev->wait.lock);
ret = kfifo_out(&cdev->events, &event, 1);
}
if (ret != 1) {
ret = -EIO;
break;