| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20241026-gpio-notify-sysfs-v3-1-ad8f127d12f5@linaro.org>
Date: Sat, 26 Oct 2024 14:58:29 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Linus Walleij <linus.walleij@...aro.org>,
Bartosz Golaszewski <brgl@...ev.pl>, Kent Gibson <warthog618@...il.com>
Cc: linux-gpio@...r.kernel.org, linux-kernel@...r.kernel.org,
Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Subject: [PATCH v3 1/5] gpio: sysfs: use cleanup guards for
gpiod_data::mutex
From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
Shrink the code and drop some goto labels by using lock guards around
gpiod_data::mutex.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
drivers/gpio/gpiolib-sysfs.c | 82 ++++++++++++++++----------------------------
1 file changed, 30 insertions(+), 52 deletions(-)
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 0c713baa7784..a0926a1061ae 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -77,12 +77,10 @@ static ssize_t direction_show(struct device *dev,
struct gpio_desc *desc = data->desc;
int value;
- mutex_lock(&data->mutex);
-
- gpiod_get_direction(desc);
- value = !!test_bit(FLAG_IS_OUT, &desc->flags);
-
- mutex_unlock(&data->mutex);
+ scoped_guard(mutex, &data->mutex) {
+ gpiod_get_direction(desc);
+ value = !!test_bit(FLAG_IS_OUT, &desc->flags);
+ }
return sysfs_emit(buf, "%s\n", value ? "out" : "in");
}
@@ -94,7 +92,7 @@ static ssize_t direction_store(struct device *dev,
struct gpio_desc *desc = data->desc;
ssize_t status;
- mutex_lock(&data->mutex);
+ guard(mutex)(&data->mutex);
if (sysfs_streq(buf, "high"))
status = gpiod_direction_output_raw(desc, 1);
@@ -105,8 +103,6 @@ static ssize_t direction_store(struct device *dev,
else
status = -EINVAL;
- mutex_unlock(&data->mutex);
-
return status ? : size;
}
static DEVICE_ATTR_RW(direction);
@@ -118,11 +114,8 @@ static ssize_t value_show(struct device *dev,
struct gpio_desc *desc = data->desc;
ssize_t status;
- mutex_lock(&data->mutex);
-
- status = gpiod_get_value_cansleep(desc);
-
- mutex_unlock(&data->mutex);
+ scoped_guard(mutex, &data->mutex)
+ status = gpiod_get_value_cansleep(desc);
if (status < 0)
return status;
@@ -140,18 +133,17 @@ static ssize_t value_store(struct device *dev,
status = kstrtol(buf, 0, &value);
- mutex_lock(&data->mutex);
+ guard(mutex)(&data->mutex);
- if (!test_bit(FLAG_IS_OUT, &desc->flags)) {
- status = -EPERM;
- } else if (status == 0) {
- gpiod_set_value_cansleep(desc, value);
- status = size;
- }
+ if (!test_bit(FLAG_IS_OUT, &desc->flags))
+ return -EPERM;
- mutex_unlock(&data->mutex);
+ if (status)
+ return status;
- return status;
+ gpiod_set_value_cansleep(desc, value);
+
+ return size;
}
static DEVICE_ATTR_PREALLOC(value, S_IWUSR | S_IRUGO, value_show, value_store);
@@ -253,11 +245,8 @@ static ssize_t edge_show(struct device *dev,
struct gpiod_data *data = dev_get_drvdata(dev);
int flags;
- mutex_lock(&data->mutex);
-
- flags = data->irq_flags;
-
- mutex_unlock(&data->mutex);
+ scoped_guard(mutex, &data->mutex)
+ flags = data->irq_flags;
if (flags >= ARRAY_SIZE(trigger_names))
return 0;
@@ -276,26 +265,22 @@ static ssize_t edge_store(struct device *dev,
if (flags < 0)
return flags;
- mutex_lock(&data->mutex);
+ guard(mutex)(&data->mutex);
- if (flags == data->irq_flags) {
- status = size;
- goto out_unlock;
- }
+ if (flags == data->irq_flags)
+ return size;
if (data->irq_flags)
gpio_sysfs_free_irq(dev);
- if (flags) {
- status = gpio_sysfs_request_irq(dev, flags);
- if (!status)
- status = size;
- }
+ if (!flags)
+ return size;
-out_unlock:
- mutex_unlock(&data->mutex);
+ status = gpio_sysfs_request_irq(dev, flags);
+ if (status)
+ return status;
- return status;
+ return size;
}
static DEVICE_ATTR_RW(edge);
@@ -330,11 +315,8 @@ static ssize_t active_low_show(struct device *dev,
struct gpio_desc *desc = data->desc;
int value;
- mutex_lock(&data->mutex);
-
- value = !!test_bit(FLAG_ACTIVE_LOW, &desc->flags);
-
- mutex_unlock(&data->mutex);
+ scoped_guard(mutex, &data->mutex)
+ value = !!test_bit(FLAG_ACTIVE_LOW, &desc->flags);
return sysfs_emit(buf, "%d\n", value);
}
@@ -350,13 +332,9 @@ static ssize_t active_low_store(struct device *dev,
if (status)
return status;
- mutex_lock(&data->mutex);
+ guard(mutex)(&data->mutex);
- status = gpio_sysfs_set_active_low(dev, value);
-
- mutex_unlock(&data->mutex);
-
- return status ? : size;
+ return gpio_sysfs_set_active_low(dev, value) ?: size;
}
static DEVICE_ATTR_RW(active_low);
--
2.45.2
Powered by blists - more mailing lists