On Fri, 23 Feb 2024 13:43:44 +0100
Nuno Sa <nuno.sa@xxxxxxxxxx> wrote:
> Use the new cleanup magic for handling mutexes in IIO. This allows us to
> greatly simplify some code paths.
>
> Note that we keep the plain mutex calls in the
> iio_device_release|acquire() APIs since in there the macros would likely
> not help much (as we want to keep the lock acquired when he leave the
> APIs).
>
> Signed-off-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
> ---
> @@ -1808,29 +1805,22 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> struct iio_ioctl_handler *h;
> int ret = -ENODEV;
>
> - mutex_lock(&iio_dev_opaque->info_exist_lock);
> -
> + guard(mutex)(&iio_dev_opaque->info_exist_lock);
> /*
> * The NULL check here is required to prevent crashing when a device
> * is being removed while userspace would still have open file handles
> * to try to access this device.
> */
> if (!indio_dev->info)
> - goto out_unlock;
> + return ret;
return -ENODEV; and drop initialisation above.
>
> list_for_each_entry(h, &iio_dev_opaque->ioctl_handlers, entry) {
> ret = h->ioctl(indio_dev, filp, cmd, arg);
> if (ret != IIO_IOCTL_UNHANDLED)
> - break;
> + return ret;
> }
>
> - if (ret == IIO_IOCTL_UNHANDLED)
> - ret = -ENODEV;
> -
> -out_unlock:
> - mutex_unlock(&iio_dev_opaque->info_exist_lock);
> -
> - return ret;
> + return -ENODEV;
> }
