watchdog: cpwd: use generic compat_ptr_ioctl

The cpwd_compat_ioctl() contains a bogus mutex that dates
back to a leftover BKL instance.

Simplify the implementation by using the new compat_ptr_ioctl()
helper function that will do the right thing for all calls
here.

Note that WIOCSTART/WIOCSTOP don't take any arguments, so
the compat_ptr() conversion is not needed here, but it also
doesn't hurt.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20190814204259.120942-6-arnd@arndb.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
This commit is contained in:
Arnd Bergmann 2019-08-14 22:42:32 +02:00 committed by Wim Van Sebroeck
parent 31bfa64e94
commit 68f28b01fb

View File

@ -473,29 +473,6 @@ static long cpwd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
return 0;
}
static long cpwd_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
int rval = -ENOIOCTLCMD;
switch (cmd) {
/* solaris ioctls are specific to this driver */
case WIOCSTART:
case WIOCSTOP:
case WIOCGSTAT:
mutex_lock(&cpwd_mutex);
rval = cpwd_ioctl(file, cmd, arg);
mutex_unlock(&cpwd_mutex);
break;
/* everything else is handled by the generic compat layer */
default:
break;
}
return rval;
}
static ssize_t cpwd_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
@ -520,7 +497,7 @@ static ssize_t cpwd_read(struct file *file, char __user *buffer,
static const struct file_operations cpwd_fops = {
.owner = THIS_MODULE,
.unlocked_ioctl = cpwd_ioctl,
.compat_ioctl = cpwd_compat_ioctl,
.compat_ioctl = compat_ptr_ioctl,
.open = cpwd_open,
.write = cpwd_write,
.read = cpwd_read,