1 files changed, 154 insertions, 66 deletions

diff --git a/net/dsa/master.c b/net/dsa/master.c
index bd44bde272f4..40367ab41cf8 100644
--- a/net/dsa/master.c
+++ b/net/dsa/master.c
@@ -58,7 +58,7 @@ static void dsa_master_get_regs(struct net_device *dev,
 	}
 
 	cpu_info = (struct ethtool_drvinfo *)data;
-	strlcpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver));
+	strscpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver));
 	data += sizeof(*cpu_info);
 	cpu_regs = (struct ethtool_regs *)data;
 	data += sizeof(*cpu_regs);
@@ -147,8 +147,7 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
 	struct dsa_switch *ds = cpu_dp->ds;
 	int port = cpu_dp->index;
 	int len = ETH_GSTRING_LEN;
-	int mcount = 0, count;
-	unsigned int i;
+	int mcount = 0, count, i;
 	uint8_t pfx[4];
 	uint8_t *ndata;
 
@@ -178,6 +177,8 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
 		 */
 		ds->ops->get_strings(ds, port, stringset, ndata);
 		count = ds->ops->get_sset_count(ds, port, stringset);
+		if (count < 0)
+			return;
 		for (i = 0; i < count; i++) {
 			memmove(ndata + (i * len + sizeof(pfx)),
 				ndata + i * len, len - sizeof(pfx));
@@ -186,17 +187,6 @@ static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
 	}
 }
 
-static int dsa_master_get_phys_port_name(struct net_device *dev,
-					 char *name, size_t len)
-{
-	struct dsa_port *cpu_dp = dev->dsa_ptr;
-
-	if (snprintf(name, len, "p%d", cpu_dp->index) >= len)
-		return -EINVAL;
-
-	return 0;
-}
-
 static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 {
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
@@ -220,18 +210,25 @@ static int dsa_master_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 		break;
 	}
 
-	if (cpu_dp->orig_ndo_ops && cpu_dp->orig_ndo_ops->ndo_do_ioctl)
-		err = cpu_dp->orig_ndo_ops->ndo_do_ioctl(dev, ifr, cmd);
+	if (dev->netdev_ops->ndo_eth_ioctl)
+		err = dev->netdev_ops->ndo_eth_ioctl(dev, ifr, cmd);
 
 	return err;
 }
 
+static const struct dsa_netdevice_ops dsa_netdev_ops = {
+	.ndo_eth_ioctl = dsa_master_ioctl,
+};
+
 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;
 	struct ethtool_ops *ops;
 
+	if (netif_is_lag_master(dev))
+		return 0;
+
 	ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
 	if (!ops)
 		return -ENOMEM;
@@ -256,53 +253,86 @@ static void dsa_master_ethtool_teardown(struct net_device *dev)
 {
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
 
+	if (netif_is_lag_master(dev))
+		return;
+
 	dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
 	cpu_dp->orig_ethtool_ops = NULL;
 }
 
-static int dsa_master_ndo_setup(struct net_device *dev)
+static void dsa_netdev_ops_set(struct net_device *dev,
+			       const struct dsa_netdevice_ops *ops)
 {
-	struct dsa_port *cpu_dp = dev->dsa_ptr;
-	struct dsa_switch *ds = cpu_dp->ds;
-	struct net_device_ops *ops;
+	if (netif_is_lag_master(dev))
+		return;
 
-	if (dev->netdev_ops->ndo_get_phys_port_name)
-		return 0;
-
-	ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
-	if (!ops)
-		return -ENOMEM;
+	dev->dsa_ptr->netdev_ops = ops;
+}
 
-	cpu_dp->orig_ndo_ops = dev->netdev_ops;
-	if (cpu_dp->orig_ndo_ops)
-		memcpy(ops, cpu_dp->orig_ndo_ops, sizeof(*ops));
+/* Keep the master always promiscuous if the tagging protocol requires that
+ * (garbles MAC DA) or if it doesn't support unicast filtering, case in which
+ * it would revert to promiscuous mode as soon as we call dev_uc_add() on it
+ * anyway.
+ */
+static void dsa_master_set_promiscuity(struct net_device *dev, int inc)
+{
+	const struct dsa_device_ops *ops = dev->dsa_ptr->tag_ops;
 
-	ops->ndo_get_phys_port_name = dsa_master_get_phys_port_name;
-	ops->ndo_do_ioctl = dsa_master_ioctl;
+	if ((dev->priv_flags & IFF_UNICAST_FLT) && !ops->promisc_on_master)
+		return;
 
-	dev->netdev_ops  = ops;
+	ASSERT_RTNL();
 
-	return 0;
+	dev_set_promiscuity(dev, inc);
 }
 
-static void dsa_master_ndo_teardown(struct net_device *dev)
+static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
+			    char *buf)
 {
+	struct net_device *dev = to_net_dev(d);
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
 
-	dev->netdev_ops = cpu_dp->orig_ndo_ops;
-	cpu_dp->orig_ndo_ops = NULL;
+	return sprintf(buf, "%s\n",
+		       dsa_tag_protocol_to_str(cpu_dp->tag_ops));
 }
 
-static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
-			    char *buf)
+static ssize_t tagging_store(struct device *d, struct device_attribute *attr,
+			     const char *buf, size_t count)
 {
+	const struct dsa_device_ops *new_tag_ops, *old_tag_ops;
 	struct net_device *dev = to_net_dev(d);
 	struct dsa_port *cpu_dp = dev->dsa_ptr;
+	int err;
 
-	return sprintf(buf, "%s\n",
-		       dsa_tag_protocol_to_str(cpu_dp->tag_ops));
+	old_tag_ops = cpu_dp->tag_ops;
+	new_tag_ops = dsa_find_tagger_by_name(buf);
+	/* Bad tagger name, or module is not loaded? */
+	if (IS_ERR(new_tag_ops))
+		return PTR_ERR(new_tag_ops);
+
+	if (new_tag_ops == old_tag_ops)
+		/* Drop the temporarily held duplicate reference, since
+		 * the DSA switch tree uses this tagger.
+		 */
+		goto out;
+
+	err = dsa_tree_change_tag_proto(cpu_dp->ds->dst, new_tag_ops,
+					old_tag_ops);
+	if (err) {
+		/* On failure the old tagger is restored, so we don't need the
+		 * driver for the new one.
+		 */
+		dsa_tag_driver_put(new_tag_ops);
+		return err;
+	}
+
+	/* On success we no longer need the module for the old tagging protocol
+	 */
+out:
+	dsa_tag_driver_put(old_tag_ops);
+	return count;
 }
-static DEVICE_ATTR_RO(tagging);
+static DEVICE_ATTR_RW(tagging);
 
 static struct attribute *dsa_slave_attrs[] = {
 	&dev_attr_tagging.attr,
@@ -314,37 +344,43 @@ static const struct attribute_group dsa_group = {
 	.attrs	= dsa_slave_attrs,
 };
 
-static void dsa_master_set_mtu(struct net_device *dev, struct dsa_port *cpu_dp)
-{
-	unsigned int mtu = ETH_DATA_LEN + cpu_dp->tag_ops->overhead;
-	int err;
-
-	rtnl_lock();
-	if (mtu <= dev->max_mtu) {
-		err = dev_set_mtu(dev, mtu);
-		if (err)
-			netdev_dbg(dev, "Unable to set MTU to include for DSA overheads\n");
-	}
-	rtnl_unlock();
-}
-
 static void dsa_master_reset_mtu(struct net_device *dev)
 {
 	int err;
 
-	rtnl_lock();
 	err = dev_set_mtu(dev, ETH_DATA_LEN);
 	if (err)
 		netdev_dbg(dev,
 			   "Unable to reset MTU to exclude DSA overheads\n");
-	rtnl_unlock();
 }
 
 int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 {
-	int ret;
+	const struct dsa_device_ops *tag_ops = cpu_dp->tag_ops;
+	struct dsa_switch *ds = cpu_dp->ds;
+	struct device_link *consumer_link;
+	int mtu, ret;
+
+	mtu = ETH_DATA_LEN + dsa_tag_protocol_overhead(tag_ops);
+
+	/* The DSA master must use SET_NETDEV_DEV for this to work. */
+	if (!netif_is_lag_master(dev)) {
+		consumer_link = device_link_add(ds->dev, dev->dev.parent,
+						DL_FLAG_AUTOREMOVE_CONSUMER);
+		if (!consumer_link)
+			netdev_err(dev,
+				   "Failed to create a device link to DSA switch %s\n",
+				   dev_name(ds->dev));
+	}
 
-	dsa_master_set_mtu(dev,  cpu_dp);
+	/* The switch driver may not implement ->port_change_mtu(), case in
+	 * which dsa_slave_change_mtu() will not update the master MTU either,
+	 * so we need to do that here.
+	 */
+	ret = dev_set_mtu(dev, mtu);
+	if (ret)
+		netdev_warn(dev, "error %d setting MTU to %d to include DSA overhead\n",
+			    ret, mtu);
 
 	/* If we use a tagging format that doesn't have an ethertype
 	 * field, make sure that all packets from this point on get
@@ -353,13 +389,14 @@ int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 	wmb();
 
 	dev->dsa_ptr = cpu_dp;
+
+	dsa_master_set_promiscuity(dev, 1);
+
 	ret = dsa_master_ethtool_setup(dev);
 	if (ret)
-		return ret;
+		goto out_err_reset_promisc;
 
-	ret = dsa_master_ndo_setup(dev);
-	if (ret)
-		goto out_err_ethtool_teardown;
+	dsa_netdev_ops_set(dev, &dsa_netdev_ops);
 
 	ret = sysfs_create_group(&dev->dev.kobj, &dsa_group);
 	if (ret)
@@ -368,18 +405,20 @@ int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
 	return ret;
 
 out_err_ndo_teardown:
-	dsa_master_ndo_teardown(dev);
-out_err_ethtool_teardown:
+	dsa_netdev_ops_set(dev, NULL);
 	dsa_master_ethtool_teardown(dev);
+out_err_reset_promisc:
+	dsa_master_set_promiscuity(dev, -1);
 	return ret;
 }
 
 void dsa_master_teardown(struct net_device *dev)
 {
 	sysfs_remove_group(&dev->dev.kobj, &dsa_group);
-	dsa_master_ndo_teardown(dev);
+	dsa_netdev_ops_set(dev, NULL);
 	dsa_master_ethtool_teardown(dev);
 	dsa_master_reset_mtu(dev);
+	dsa_master_set_promiscuity(dev, -1);
 
 	dev->dsa_ptr = NULL;
 
@@ -389,3 +428,52 @@ void dsa_master_teardown(struct net_device *dev)
 	 */
 	wmb();
 }
+
+int dsa_master_lag_setup(struct net_device *lag_dev, struct dsa_port *cpu_dp,
+			 struct netdev_lag_upper_info *uinfo,
+			 struct netlink_ext_ack *extack)
+{
+	bool master_setup = false;
+	int err;
+
+	if (!netdev_uses_dsa(lag_dev)) {
+		err = dsa_master_setup(lag_dev, cpu_dp);
+		if (err)
+			return err;
+
+		master_setup = true;
+	}
+
+	err = dsa_port_lag_join(cpu_dp, lag_dev, uinfo, extack);
+	if (err) {
+		if (extack && !extack->_msg)
+			NL_SET_ERR_MSG_MOD(extack,
+					   "CPU port failed to join LAG");
+		goto out_master_teardown;
+	}
+
+	return 0;
+
+out_master_teardown:
+	if (master_setup)
+		dsa_master_teardown(lag_dev);
+	return err;
+}
+
+/* Tear down a master if there isn't any other user port on it,
+ * optionally also destroying LAG information.
+ */
+void dsa_master_lag_teardown(struct net_device *lag_dev,
+			     struct dsa_port *cpu_dp)
+{
+	struct net_device *upper;
+	struct list_head *iter;
+
+	dsa_port_lag_leave(cpu_dp, lag_dev);
+
+	netdev_for_each_upper_dev_rcu(lag_dev, upper, iter)
+		if (dsa_slave_dev_check(upper))
+			return;
+
+	dsa_master_teardown(lag_dev);
+}