[PATCH 280/437] watchdog: wdt: convert to read/write iterators

Jens Axboe
2024-04-11T15:39:25Z

drivers/watchdog/wdt.c | 28 ++++++++++++----------------
1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/drivers/watchdog/wdt.c b/drivers/watchdog/wdt.c
index 183876156243..4f942a82271b 100644
--- a/drivers/watchdog/wdt.c
+++ b/drivers/watchdog/wdt.c
@@ -305,18 +305,17 @@ static irqreturn_t wdt_interrupt(int irq, void *dev_id)

/**
* wdt_write:
- * @file: file handle to the watchdog
- * @buf: buffer to write (unused as data does not matter here
- * @count: count of bytes
- * @ppos: pointer to the position to write. No seeks allowed
+ * @iocb: metadata for the request
+ * @from: iov_iter to read from
*
* A write to a watchdog device is defined as a keepalive signal. Any
* write of data will do, as we we don't define content meaning.
*/

-static ssize_t wdt_write(struct file *file, const char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t wdt_write(struct kiocb *iocb, struct iov_iter *from)
{
+ size_t count = iov_iter_count(from);
+
if (count) {
if (!nowayout) {
size_t i;
@@ -326,7 +325,7 @@ static ssize_t wdt_write(struct file *file, const char __user *buf,

for (i = 0; i != count; i++) {
char c;
- if (get_user(c, buf + i))
+ if (get_iter(c, from))
return -EFAULT;
if (c == 'V')
expect_close = 42;
@@ -447,21 +446,18 @@ static int wdt_release(struct inode *inode, struct file *file)

/**
* wdt_temp_read:
- * @file: file handle to the watchdog board
- * @buf: buffer to write 1 byte into
- * @count: length of buffer
- * @ptr: offset (no seek allowed)
+ * @iocb: metadata for the request
+ * @to: iov_iter to write to
*
* Temp_read reports the temperature in degrees Fahrenheit. The API is in
* farenheit. It was designed by an imperial measurement luddite.
*/

-static ssize_t wdt_temp_read(struct file *file, char __user *buf,
- size_t count, loff_t *ptr)
+static ssize_t wdt_temp_read(struct kiocb *iocb, struct iov_iter *to)
{
int temperature = wdt_get_temperature();

- if (copy_to_user(buf, &temperature, 1))
+ if (!copy_to_iter_full(&temperature, 1, to))
return -EFAULT;

return 1;
@@ -521,7 +517,7 @@ static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
static const struct file_operations wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
- .write = wdt_write,
+ .write_iter = wdt_write,
.unlocked_ioctl = wdt_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.open = wdt_open,
@@ -537,7 +533,7 @@ static struct miscdevice wdt_miscdev = {
static const struct file_operations wdt_temp_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
- .read = wdt_temp_read,
+ .read_iter = wdt_temp_read,
.open = wdt_temp_open,
.release = wdt_temp_release,
};
--
2.43.0