[PATCH v2 net-next 07/12] net: switchdev: export switchdev_lower_dev_find

[Vladimir Oltean <vladimir.oltean@nxp.com>]

This little function that retrieves the first lower interface of @dev
that passes the @check_cb and @foreign_dev_check_cb criteria is useful
outside of the switchdev core, too. For example, drivers may use it to
retrieve a pointer to one of their own netdevices beneath a LAG.

Export it for driver use, to reduce code duplication.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 include/net/switchdev.h   | 6 ++++++
 net/switchdev/switchdev.c | 3 ++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index d353793dfeb5..40b348f9898c 100644
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h
@@ -299,6 +299,12 @@ void switchdev_port_fwd_mark_set(struct net_device *dev,
 				 struct net_device *group_dev,
 				 bool joining);
 
+struct net_device *
+switchdev_lower_dev_find(struct net_device *dev,
+			 bool (*check_cb)(const struct net_device *dev),
+			 bool (*foreign_dev_check_cb)(const struct net_device *dev,
+						      const struct net_device *foreign_dev));
+
 int switchdev_handle_fdb_event_to_device(struct net_device *dev, unsigned long event,
 		const struct switchdev_notifier_fdb_info *fdb_info,
 		bool (*check_cb)(const struct net_device *dev),
diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index b62565278fac..85a84fe6eff3 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -408,7 +408,7 @@ static int switchdev_lower_dev_walk(struct net_device *lower_dev,
 	return 0;
 }
 
-static struct net_device *
+struct net_device *
 switchdev_lower_dev_find(struct net_device *dev,
 			 bool (*check_cb)(const struct net_device *dev),
 			 bool (*foreign_dev_check_cb)(const struct net_device *dev,
@@ -428,6 +428,7 @@ switchdev_lower_dev_find(struct net_device *dev,
 
 	return switchdev_priv.lower_dev;
 }
+EXPORT_SYMBOL_GPL(switchdev_lower_dev_find);
 
 static int __switchdev_handle_fdb_event_to_device(struct net_device *dev,
 		struct net_device *orig_dev, unsigned long event,
-- 
2.25.1