On Wed, 21 Feb 2024 14:26:52 +0100
Nuno Sa via B4 Relay <devnull+nuno.sa.analog.com@xxxxxxxxxx> wrote:
> From: Nuno Sa <nuno.sa@xxxxxxxxxx>
>
> 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>
> ---
> drivers/iio/industrialio-core.c | 52 +++++++++++++++--------------------------
> 1 file changed, 19 insertions(+), 33 deletions(-)
>
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index 9b2877fe8689..7e6497828364 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -11,6 +11,7 @@
> @@ -1806,31 +1803,22 @@ static long iio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> struct iio_dev *indio_dev = ib->indio_dev;
> struct iio_dev_opaque *iio_dev_opaque = to_iio_dev_opaque(indio_dev);
> 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 -ENODEV;
>
> 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;
> + if (h->ioctl(indio_dev, filp, cmd, arg) != IIO_IOCTL_UNHANDLED)
> + return 0;
Changes the return value if ret returns something other than IIO_IOCTL_UNHANDLED
which it can I think...
> }
>
> - if (ret == IIO_IOCTL_UNHANDLED)
> - ret = -ENODEV;
> -
> -out_unlock:
> - mutex_unlock(&iio_dev_opaque->info_exist_lock);
> -
> - return ret;
> + return -ENODEV;
> }
