[PATCH net-next 1/2] dsa: bonding: implement HW bonding

[Jonas Johansson <jonasj76@gmail.com>]

From: Jonas Johansson <jonas.johansson@westermo.se>

This patch will implement hooks for hardware bonding support for the DSA
driver. When the team driver adds a DSA slave port the port will be assigned
a bond group id and the DSA slave driver can setup the hardware. When team
changes the port state (enabled/disabled) the DSA slave driver is able to
use the attach/detach callback which will allow the hardware to change the
hardware settings to reflect the state.

Added DSA hooks:
 bond_add_group: To add a port to a bond group
 bond_del_group: To remove a port from a bond group
 bond_attach: To mark the port in a bond group as attached/active
 bond_detach: To unmark the port in a bond group as detach/inactive

Added new network device hooks:
 ndo_bond_attach: To attach a device to a bond group.
 ndo_bond_detach: To detach a device from a bond group.

Team:
 Added callback to ndo_bond_attach when port is enabled.
 Added callback to ndo_bond_detach when port is disabled.

Added DSA notifier:
 Listening on NETDEV_CHANGEUPPER to add or deleta a port to/from a bond group.

Signed-off-by: Jonas Johansson <jonas.johansson@westermo.se>
---
 drivers/net/team/team.c   |  4 ++++
 include/linux/netdevice.h |  8 +++++++
 include/net/dsa.h         |  8 +++++++
 net/dsa/dsa.c             | 60 +++++++++++++++++++++++++++++++++++++++++++++++
 net/dsa/dsa_priv.h        |  6 +++++
 net/dsa/slave.c           | 23 ++++++++++++++++++
 6 files changed, 109 insertions(+)

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index 0e62274..f7b2afb 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -934,6 +934,8 @@ static void team_port_enable(struct team *team,
 		team->ops.port_enabled(team, port);
 	team_notify_peers(team);
 	team_mcast_rejoin(team);
+	if (port->dev->netdev_ops->ndo_bond_attach)
+		port->dev->netdev_ops->ndo_bond_attach(port->dev);
 }
 
 static void __reconstruct_port_hlist(struct team *team, int rm_index)
@@ -965,6 +967,8 @@ static void team_port_disable(struct team *team,
 	team_adjust_ops(team);
 	team_notify_peers(team);
 	team_mcast_rejoin(team);
+	if (port->dev->netdev_ops->ndo_bond_detach)
+		port->dev->netdev_ops->ndo_bond_detach(port->dev);
 }
 
 #define TEAM_VLAN_FEATURES (NETIF_F_ALL_CSUM | NETIF_F_SG | \
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 5897b4e..8ebaefa 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -939,6 +939,12 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
  * int (*ndo_del_slave)(struct net_device *dev, struct net_device *slave_dev);
  *	Called to release previously enslaved netdev.
  *
+ * int (*ndo_bond_attach)(struct net_device *dev);
+ *	Called to attach the device to a bond group.
+ *
+ * int (*ndo_bond_detach)(struct net_device *dev);
+ *	Called to detach the device from a bond group.
+ *
  *      Feature/offload setting functions.
  * netdev_features_t (*ndo_fix_features)(struct net_device *dev,
  *		netdev_features_t features);
@@ -1131,6 +1137,8 @@ struct net_device_ops {
 						 struct net_device *slave_dev);
 	int			(*ndo_del_slave)(struct net_device *dev,
 						 struct net_device *slave_dev);
+	int			(*ndo_bond_attach)(struct net_device *dev);
+	int			(*ndo_bond_detach)(struct net_device *dev);
 	netdev_features_t	(*ndo_fix_features)(struct net_device *dev,
 						    netdev_features_t features);
 	int			(*ndo_set_features)(struct net_device *dev,
diff --git a/include/net/dsa.h b/include/net/dsa.h
index ed3c34b..64b5963 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -254,6 +254,14 @@ struct dsa_switch_driver {
 	int	(*get_eee)(struct dsa_switch *ds, int port,
 			   struct ethtool_eee *e);
 
+	/*
+	 * Bonding
+	 */
+	int	(*bond_add_group)(struct dsa_switch *ds, int port, int gid);
+	int	(*bond_del_group)(struct dsa_switch *ds, int port, int gid);
+	int	(*bond_attach)(struct dsa_switch *ds, int port);
+	int	(*bond_detach)(struct dsa_switch *ds, int port);
+
 #ifdef CONFIG_NET_DSA_HWMON
 	/* Hardware monitoring */
 	int	(*get_temp)(struct dsa_switch *ds, int *temp);
diff --git a/net/dsa/dsa.c b/net/dsa/dsa.c
index 2173402..3d2c599 100644
--- a/net/dsa/dsa.c
+++ b/net/dsa/dsa.c
@@ -17,6 +17,7 @@
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <net/dsa.h>
+#include <net/rtnetlink.h>
 #include <linux/of.h>
 #include <linux/of_mdio.h>
 #include <linux/of_platform.h>
@@ -442,6 +443,62 @@ static void dsa_link_poll_timer(unsigned long _dst)
 	schedule_work(&dst->link_poll_work);
 }
 
+/* net device notifier event handler ****************************************/
+static int dsa_master_changed(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->parent;
+	struct net_device *master = netdev_master_upper_dev_get(dev);
+	int err = 0;
+
+	/* Add port to bond group */
+	if (master && master->rtnl_link_ops &&
+	    !strcmp(master->rtnl_link_ops->kind, "team")) {
+
+		p->bond_gid = master->ifindex;
+
+		if (!ds->drv->bond_add_group)
+			return -EOPNOTSUPP;
+		return ds->drv->bond_add_group(ds, p->port, p->bond_gid);
+	}
+
+	/* Remove port from bond group */
+	if (!master && p->bond_gid) {
+		if (!ds->drv->bond_del_group)
+			return -EOPNOTSUPP;
+		err = ds->drv->bond_del_group(ds, p->port, p->bond_gid);
+		p->bond_gid = 0;
+		return err;
+	}
+
+	return 0;
+}
+
+static int dsa_event(struct notifier_block *nb, unsigned long event, void *data)
+
+{
+	struct net_device *dev;
+	int err = 0;
+
+	switch (event) {
+	case NETDEV_CHANGEUPPER:
+		dev = netdev_notifier_info_to_dev(data);
+		if (!dsa_slave_check(dev))
+			return NOTIFY_DONE;
+		err = dsa_master_changed(dev);
+		if (err)
+			netdev_warn(dev,
+				    "failed to reflect master change (err %d)\n",
+				    err);
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block dsa_nb __read_mostly = {
+	.notifier_call = dsa_event,
+};
 
 /* platform driver init and cleanup *****************************************/
 static int dev_is_class(struct device *dev, void *class)
@@ -778,6 +835,9 @@ static int dsa_probe(struct platform_device *pdev)
 		add_timer(&dst->link_poll_timer);
 	}
 
+	/* Setup notifier */
+	register_netdevice_notifier(&dsa_nb);
+
 	return 0;
 
 out:
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index dc9756d..6a1456a 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -45,6 +45,11 @@ struct dsa_slave_priv {
 	int			old_link;
 	int			old_pause;
 	int			old_duplex;
+
+	/*
+	 * Bond group id, or 0 if port is not bonded.
+	 */
+	int			bond_gid;
 };
 
 /* dsa.c */
@@ -58,6 +63,7 @@ struct net_device *dsa_slave_create(struct dsa_switch *ds,
 				    int port, char *name);
 int dsa_slave_suspend(struct net_device *slave_dev);
 int dsa_slave_resume(struct net_device *slave_dev);
+bool dsa_slave_check(struct net_device *dev);
 
 /* tag_dsa.c */
 extern const struct dsa_device_ops dsa_netdev_ops;
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index f23dead..88c84bf 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -441,6 +441,22 @@ static int dsa_slave_get_eee(struct net_device *dev, struct ethtool_eee *e)
 	return ret;
 }
 
+static int dsa_slave_bond_attach(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->parent;
+
+	return ds->drv->bond_attach(ds, p->port);
+}
+
+static int dsa_slave_bond_detach(struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct dsa_switch *ds = p->parent;
+
+	return ds->drv->bond_detach(ds, p->port);
+}
+
 static const struct ethtool_ops dsa_slave_ethtool_ops = {
 	.get_settings		= dsa_slave_get_settings,
 	.set_settings		= dsa_slave_set_settings,
@@ -470,6 +486,8 @@ static const struct net_device_ops dsa_slave_netdev_ops = {
 	.ndo_set_rx_mode	= dsa_slave_set_rx_mode,
 	.ndo_set_mac_address	= dsa_slave_set_mac_address,
 	.ndo_do_ioctl		= dsa_slave_ioctl,
+	.ndo_bond_attach	= dsa_slave_bond_attach,
+	.ndo_bond_detach	= dsa_slave_bond_detach,
 };
 
 static void dsa_slave_adjust_link(struct net_device *dev)
@@ -574,6 +592,11 @@ static int dsa_slave_phy_setup(struct dsa_slave_priv *p,
 	return 0;
 }
 
+bool dsa_slave_check(struct net_device *ndev)
+{
+	return ndev->netdev_ops == &dsa_slave_netdev_ops;
+}
+
 int dsa_slave_suspend(struct net_device *slave_dev)
 {
 	struct dsa_slave_priv *p = netdev_priv(slave_dev);
-- 
2.1.0