[PATCH] stmmac: debugfs entry name is not be changed when udev rename device name.

[Jiping Ma]

Add one notifier for udev changes net device name.

Signed-off-by: Jiping Ma <jiping.ma2@xxxxxxxxxxxxx>
---
 .../net/ethernet/stmicro/stmmac/stmmac_main.c | 38 ++++++++++++++++++-
 1 file changed, 37 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index b14f46a57154..c1c877bb4421 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -4038,6 +4038,40 @@ static int stmmac_dma_cap_show(struct seq_file *seq, void *v)
 }
 DEFINE_SHOW_ATTRIBUTE(stmmac_dma_cap);
 
+/**
+ * Use network device events to create/remove/rename
+ * debugfs file entries
+ */
+static int stmmac_device_event(struct notifier_block *unused,
+			       unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	struct stmmac_priv *priv = netdev_priv(dev);
+
+	switch (event) {
+	case NETDEV_CHANGENAME:
+		if (priv->dbgfs_dir)
+			priv->dbgfs_dir = debugfs_rename(stmmac_fs_dir,
+							 priv->dbgfs_dir,
+							 stmmac_fs_dir,
+							 dev->name);
+		break;
+
+	case NETDEV_GOING_DOWN:
+		break;
+
+	case NETDEV_UP:
+		break;
+	}
+
+done:
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block stmmac_notifier = {
+	.notifier_call = stmmac_device_event,
+};
+
 static int stmmac_init_fs(struct net_device *dev)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
@@ -4050,7 +4084,6 @@ static int stmmac_init_fs(struct net_device *dev)
 
 		return -ENOMEM;
 	}
-
 	/* Entry to report DMA RX/TX rings */
 	priv->dbgfs_rings_status =
 		debugfs_create_file("descriptors_status", 0444,
@@ -4076,6 +4109,8 @@ static int stmmac_init_fs(struct net_device *dev)
 		return -ENOMEM;
 	}
 
+	register_netdevice_notifier(&stmmac_notifier);
+
 	return 0;
 }
 
@@ -4083,6 +4118,7 @@ static void stmmac_exit_fs(struct net_device *dev)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
 
+	unregister_netdevice_notifier(&stmmac_notifier);
 	debugfs_remove_recursive(priv->dbgfs_dir);
 }
 #endif /* CONFIG_DEBUG_FS */
-- 
2.23.0