[PATCH 1/2] iio:core: Introduce unlocked version of iio_map_array_unregister()

From: Lino Sanfilippo
Date: Sat Oct 17 2020 - 21:14:38 EST


Introduce an unlocked version of iio_map_array_unregister(). This function
can help to unwind in case of error while the iio_map_list_lock mutex is
held.

Signed-off-by: Lino Sanfilippo <LinoSanfilippo@xxxxxx>
---
drivers/iio/inkern.c | 27 ++++++++++++++++++---------
1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index ede99e0..39c1d63 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -24,6 +24,21 @@ struct iio_map_internal {
static LIST_HEAD(iio_map_list);
static DEFINE_MUTEX(iio_map_list_lock);

+static int iio_map_array_unregister_locked(struct iio_dev *indio_dev)
+{
+ int ret = -ENODEV;
+ struct iio_map_internal *mapi, *next;
+
+ list_for_each_entry_safe(mapi, next, &iio_map_list, l) {
+ if (indio_dev == mapi->indio_dev) {
+ list_del(&mapi->l);
+ kfree(mapi);
+ ret = 0;
+ }
+ }
+ return ret;
+}
+
int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps)
{
int i = 0, ret = 0;
@@ -57,18 +72,12 @@ EXPORT_SYMBOL_GPL(iio_map_array_register);
*/
int iio_map_array_unregister(struct iio_dev *indio_dev)
{
- int ret = -ENODEV;
- struct iio_map_internal *mapi, *next;
+ int ret;

mutex_lock(&iio_map_list_lock);
- list_for_each_entry_safe(mapi, next, &iio_map_list, l) {
- if (indio_dev == mapi->indio_dev) {
- list_del(&mapi->l);
- kfree(mapi);
- ret = 0;
- }
- }
+ ret = iio_map_array_unregister_locked(indio_dev);
mutex_unlock(&iio_map_list_lock);
+
return ret;
}
EXPORT_SYMBOL_GPL(iio_map_array_unregister);
--
2.7.4