net: dsa: setup and teardown master device

Add DSA helpers to setup and teardown a master net device wired to its
CPU port. This centralizes the dsa_ptr assignment.

This also makes the master ethtool helpers static at the same time.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dsa/dsa2.c

@@ -469,6 +469,23 @@ static void dsa_ds_unapply(struct dsa_switch_tree *dst, struct dsa_switch *ds)
 
 }
 
+static int dsa_tree_setup_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp = dst->cpu_dp;
+	struct net_device *master = cpu_dp->master;
+
+	/* DSA currently supports a single pair of CPU port and master device */
+	return dsa_master_setup(master, cpu_dp);
+}
+
+static void dsa_tree_teardown_master(struct dsa_switch_tree *dst)
+{
+	struct dsa_port *cpu_dp = dst->cpu_dp;
+	struct net_device *master = cpu_dp->master;
+
+	return dsa_master_teardown(master);
+}
+
 static int dsa_dst_apply(struct dsa_switch_tree *dst)
 {
 	struct dsa_switch *ds;
@@ -489,14 +506,7 @@ static int dsa_dst_apply(struct dsa_switch_tree *dst)
 			return err;
 	}
 
-	/* If we use a tagging format that doesn't have an ethertype
-	 * field, make sure that all packets from this point on get
-	 * sent to the tag format's receive function.
-	 */
-	wmb();
-	dst->cpu_dp->master->dsa_ptr = dst->cpu_dp;
-
-	err = dsa_master_ethtool_setup(dst->cpu_dp->master);
+	err = dsa_tree_setup_master(dst);
 	if (err)
 		return err;
 
@@ -513,15 +523,7 @@ static void dsa_dst_unapply(struct dsa_switch_tree *dst)
 	if (!dst->applied)
 		return;
 
-	dsa_master_ethtool_restore(dst->cpu_dp->master);
-
-	dst->cpu_dp->master->dsa_ptr = NULL;
-
-	/* If we used a tagging format that doesn't have an ethertype
-	 * field, make sure that all packets from this point get sent
-	 * without the tag and go through the regular receive path.
-	 */
-	wmb();
+	dsa_tree_teardown_master(dst);
 
 	for (index = 0; index < DSA_MAX_SWITCHES; index++) {
 		ds = dst->ds[index];

net/dsa/dsa_priv.h

@@ -108,8 +108,8 @@ int dsa_legacy_fdb_del(struct ndmsg *ndm, struct nlattr *tb[],
 		       const unsigned char *addr, u16 vid);
 
 /* master.c */
-int dsa_master_ethtool_setup(struct net_device *dev);
-void dsa_master_ethtool_restore(struct net_device *dev);
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp);
+void dsa_master_teardown(struct net_device *dev);
 
 static inline struct net_device *dsa_master_find_slave(struct net_device *dev,
 						       int device, int port)

net/dsa/legacy.c

@@ -593,15 +593,7 @@ static int dsa_setup_dst(struct dsa_switch_tree *dst, struct net_device *dev,
 	if (!configured)
 		return -EPROBE_DEFER;
 
-	/*
-	 * If we use a tagging format that doesn't have an ethertype
-	 * field, make sure that all packets from this point on get
-	 * sent to the tag format's receive function.
-	 */
-	wmb();
-	dev->dsa_ptr = dst->cpu_dp;
-
-	return dsa_master_ethtool_setup(dst->cpu_dp->master);
+	return dsa_master_setup(dst->cpu_dp->master, dst->cpu_dp);
 }
 
 static int dsa_probe(struct platform_device *pdev)
@@ -666,15 +658,7 @@ static void dsa_remove_dst(struct dsa_switch_tree *dst)
 {
 	int i;
 
-	dsa_master_ethtool_restore(dst->cpu_dp->master);
-
-	dst->cpu_dp->master->dsa_ptr = NULL;
-
-	/* If we used a tagging format that doesn't have an ethertype
-	 * field, make sure that all packets from this point get sent
-	 * without the tag and go through the regular receive path.
-	 */
-	wmb();
+	dsa_master_teardown(dst->cpu_dp->master);
 
 	for (i = 0; i < dst->pd->nr_chips; i++) {
 		struct dsa_switch *ds = dst->ds[i];

net/dsa/master.c

@@ -85,7 +85,7 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
 	}
 }
 
-int dsa_master_ethtool_setup(struct net_device *dev)
+static int dsa_master_ethtool_setup(struct net_device *dev)
 {
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
 	struct dsa_switch *ds = cpu_dp->ds;
@@ -108,10 +108,36 @@ int dsa_master_ethtool_setup(struct net_device *dev)
 	return 0;
 }
 
-void dsa_master_ethtool_restore(struct net_device *dev)
+static void dsa_master_ethtool_teardown(struct net_device *dev)
 {
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
 
 	dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
 	cpu_dp->orig_ethtool_ops = NULL;
 }
+
+int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
+{
+	/* If we use a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point on get
+	 * sent to the tag format's receive function.
+	 */
+	wmb();
+
+	dev->dsa_ptr = cpu_dp;
+
+	return dsa_master_ethtool_setup(dev);
+}
+
+void dsa_master_teardown(struct net_device *dev)
+{
+	dsa_master_ethtool_teardown(dev);
+
+	dev->dsa_ptr = NULL;
+
+	/* If we used a tagging format that doesn't have an ethertype
+	 * field, make sure that all packets from this point get sent
+	 * without the tag and go through the regular receive path.
+	 */
+	wmb();
+}