[PATCH v5 net-next 05/10] net: marvell: prestera: refactor prechangeupper sanity checks

[Vladimir Oltean <vladimir.oltean@xxxxxxx>]

In preparation of adding more code to the NETDEV_PRECHANGEUPPER handler,
move the existing sanity checks into a dedicated function.

Cc: Vadym Kochan <vkochan@xxxxxxxxxxx>
Cc: Taras Chornyi <tchornyi@xxxxxxxxxxx>
Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
v2->v3: patch is new
v3->v4: none
v4->v5: none

 .../ethernet/marvell/prestera/prestera_main.c | 71 ++++++++++++-------
 1 file changed, 44 insertions(+), 27 deletions(-)

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c b/drivers/net/ethernet/marvell/prestera/prestera_main.c
index 226f4ff29f6e..1f3c8cd6ced2 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_main.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c
@@ -699,6 +699,45 @@ static bool prestera_lag_master_check(struct net_device *lag_dev,
 	return true;
 }
 
+static int prestera_prechangeupper_sanity_checks(struct net_device *dev,
+						 struct net_device *upper,
+						 struct netdev_notifier_changeupper_info *info,
+						 struct netlink_ext_ack *extack)
+{
+	if (!netif_is_bridge_master(upper) &&
+	    !netif_is_lag_master(upper)) {
+		NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
+		return -EINVAL;
+	}
+
+	if (!info->linking)
+		return 0;
+
+	if (netdev_has_any_upper_dev(upper)) {
+		NL_SET_ERR_MSG_MOD(extack, "Upper device is already enslaved");
+		return -EINVAL;
+	}
+
+	if (netif_is_lag_master(upper) &&
+	    !prestera_lag_master_check(upper, info->upper_info, extack))
+		return -EOPNOTSUPP;
+
+	if (netif_is_lag_master(upper) && vlan_uses_dev(dev)) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Master device is a LAG master and port has a VLAN");
+		return -EINVAL;
+	}
+
+	if (netif_is_lag_port(dev) && is_vlan_dev(upper) &&
+	    !netif_is_lag_master(vlan_dev_real_dev(upper))) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Can not put a VLAN on a LAG port");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int prestera_netdev_port_event(struct net_device *lower,
 				      struct net_device *dev,
 				      unsigned long event, void *ptr)
@@ -707,40 +746,18 @@ static int prestera_netdev_port_event(struct net_device *lower,
 	struct prestera_port *port = netdev_priv(dev);
 	struct netlink_ext_ack *extack;
 	struct net_device *upper;
+	int err;
 
 	extack = netdev_notifier_info_to_extack(&info->info);
 	upper = info->upper_dev;
 
 	switch (event) {
 	case NETDEV_PRECHANGEUPPER:
-		if (!netif_is_bridge_master(upper) &&
-		    !netif_is_lag_master(upper)) {
-			NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
-			return -EINVAL;
-		}
-
-		if (!info->linking)
-			break;
-
-		if (netdev_has_any_upper_dev(upper)) {
-			NL_SET_ERR_MSG_MOD(extack, "Upper device is already enslaved");
-			return -EINVAL;
-		}
+		err = prestera_prechangeupper_sanity_checks(dev, upper, info,
+							    extack);
+		if (err)
+			return err;
 
-		if (netif_is_lag_master(upper) &&
-		    !prestera_lag_master_check(upper, info->upper_info, extack))
-			return -EOPNOTSUPP;
-		if (netif_is_lag_master(upper) && vlan_uses_dev(dev)) {
-			NL_SET_ERR_MSG_MOD(extack,
-					   "Master device is a LAG master and port has a VLAN");
-			return -EINVAL;
-		}
-		if (netif_is_lag_port(dev) && is_vlan_dev(upper) &&
-		    !netif_is_lag_master(vlan_dev_real_dev(upper))) {
-			NL_SET_ERR_MSG_MOD(extack,
-					   "Can not put a VLAN on a LAG port");
-			return -EINVAL;
-		}
 		break;
 
 	case NETDEV_CHANGEUPPER:
-- 
2.25.1