[PATCH v3] staging: fieldbus: use sysfs_emit() in show functions

From: Deepak R Varma
Date: Wed Nov 09 2022 - 05:43:33 EST


The show() methods should only use sysfs_emit() when formatting values
to be returned to the user space.
Ref: Documentation/filesystems/sysfs.rst
Issue identified by coccicheck.

Signed-off-by: Deepak R Varma <drv@xxxxxxxxx>
---
Changes in v3:
1. Include other show functions from the same file in the scope of this
patch. Feedback from gregkh@xxxxxxxxxxxxxxxxxxx
2. Simplify code comment.

Changes in v2:
1. Switch to using sysfs_emit instead of scnprintf
2. Update patch subject and log accordingly
Feedback from gregkh@xxxxxxxxxxxxxxxxxxx


drivers/staging/fieldbus/dev_core.c | 17 +++++++----------
1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/staging/fieldbus/dev_core.c b/drivers/staging/fieldbus/dev_core.c
index 5aab734606ea..5f54f2674bd1 100644
--- a/drivers/staging/fieldbus/dev_core.c
+++ b/drivers/staging/fieldbus/dev_core.c
@@ -28,7 +28,7 @@ static ssize_t online_show(struct device *dev, struct device_attribute *attr,
{
struct fieldbus_dev *fb = dev_get_drvdata(dev);

- return sprintf(buf, "%d\n", !!fb->online);
+ return sysfs_emit(buf, "%d\n", !!fb->online);
}
static DEVICE_ATTR_RO(online);

@@ -39,7 +39,7 @@ static ssize_t enabled_show(struct device *dev, struct device_attribute *attr,

if (!fb->enable_get)
return -EINVAL;
- return sprintf(buf, "%d\n", !!fb->enable_get(fb));
+ return sysfs_emit(buf, "%d\n", !!fb->enable_get(fb));
}

static ssize_t enabled_store(struct device *dev, struct device_attribute *attr,
@@ -66,11 +66,8 @@ static ssize_t card_name_show(struct device *dev, struct device_attribute *attr,
{
struct fieldbus_dev *fb = dev_get_drvdata(dev);

- /*
- * card_name was provided by child driver, could potentially be long.
- * protect against buffer overrun.
- */
- return snprintf(buf, PAGE_SIZE, "%s\n", fb->card_name);
+ /* card_name was provided by child driver. */
+ return sysfs_emit(buf, "%s\n", fb->card_name);
}
static DEVICE_ATTR_RO(card_name);

@@ -79,7 +76,7 @@ static ssize_t read_area_size_show(struct device *dev,
{
struct fieldbus_dev *fb = dev_get_drvdata(dev);

- return sprintf(buf, "%zu\n", fb->read_area_sz);
+ return sysfs_emit(buf, "%zu\n", fb->read_area_sz);
}
static DEVICE_ATTR_RO(read_area_size);

@@ -88,7 +85,7 @@ static ssize_t write_area_size_show(struct device *dev,
{
struct fieldbus_dev *fb = dev_get_drvdata(dev);

- return sprintf(buf, "%zu\n", fb->write_area_sz);
+ return sysfs_emit(buf, "%zu\n", fb->write_area_sz);
}
static DEVICE_ATTR_RO(write_area_size);

@@ -116,7 +113,7 @@ static ssize_t fieldbus_type_show(struct device *dev,
break;
}

- return sprintf(buf, "%s\n", t);
+ return sysfs_emit(buf, "%s\n", t);
}
static DEVICE_ATTR_RO(fieldbus_type);

--
2.34.1