Merge branch 'mlxsw-VRRP'

Ido Schimmel says:

====================
mlxsw: Add VRRP support

When a router that is acting as the default gateway of a host stops
functioning, the host will encounter packet loss until the router starts
functioning again.

To increase the reliability of the default gateway without performing
reconfiguration on the host, a host can use a Virtual Router Redundancy
Protocol (VRRP) Router. This virtual router is composed from several
routers where only one is actually forwarding packets from the host (the
master router) while the other routers act as backup routers. The
election of the master router is determined by the VRRP protocol [1].

Packets addressed to the virtual router are always sent to the virtual
router MAC address (IPv4: 00-00-5E-00-01-XX, IPv6: 00-00-5E-00-02-XX).
Such packets can only be accepted by the master router and must be
discarded by the backup routers.

In Linux, VRRP is usually implemented by configuring a macvlan with the
virtual router MAC on top of the router interface that is connected to
the host / LAN. The macvlan on the master router is assigned the virtual
IP (VIP) that the host uses as its gateway.

In order to support VRRP in mlxsw, we first need to enable macvlan upper
devices on top of mlxsw netdevs and their uppers. This is done by the
first patch, which also takes care of sanitizing macvlan configurations
that are not currently supported by the driver.

The second patch directs packets with destination MAC addresses as the
macvlans to the router so that they will undergo an L3 lookup. This is
consistent with the kernel's behavior where the macvlan's Rx handler
will re-inject such packets to the Rx path so that they will be picked
up by the IPvX protocol handlers and undergo an L3 lookup. Note that the
driver prevents the macvlans from being enslaved to other devices, to
ensure the packets will be picked up by the protocol handler and not by
another Rx handler.

The third patch adds packet traps for VRRP control packets for both IPv4
and IPv6. Finally, the last patch optimizes the reception of VRRP MACs
by potentially skipping one L2 lookup for them.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/reg.h

@@ -4353,6 +4353,20 @@ MLXSW_ITEM32(reg, ritr, if_swid, 0x08, 24, 8);
  */
 MLXSW_ITEM_BUF(reg, ritr, if_mac, 0x12, 6);
 
+/* reg_ritr_if_vrrp_id_ipv6
+ * VRRP ID for IPv6
+ * Note: Reserved for RIF types other than VLAN, FID and Sub-port.
+ * Access: RW
+ */
+MLXSW_ITEM32(reg, ritr, if_vrrp_id_ipv6, 0x1C, 8, 8);
+
+/* reg_ritr_if_vrrp_id_ipv4
+ * VRRP ID for IPv4
+ * Note: Reserved for RIF types other than VLAN, FID and Sub-port.
+ * Access: RW
+ */
+MLXSW_ITEM32(reg, ritr, if_vrrp_id_ipv4, 0x1C, 0, 8);
+
 /* VLAN Interface */
 
 /* reg_ritr_vlan_if_vid

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -3386,6 +3386,8 @@ static const struct mlxsw_listener mlxsw_sp_listener[] = {
 	MLXSW_SP_RXL_MARK(ROUTER_ALERT_IPV4, TRAP_TO_CPU, ROUTER_EXP, false),
 	MLXSW_SP_RXL_MARK(ROUTER_ALERT_IPV6, TRAP_TO_CPU, ROUTER_EXP, false),
 	MLXSW_SP_RXL_MARK(IPIP_DECAP_ERROR, TRAP_TO_CPU, ROUTER_EXP, false),
+	MLXSW_SP_RXL_MARK(IPV4_VRRP, TRAP_TO_CPU, ROUTER_EXP, false),
+	MLXSW_SP_RXL_MARK(IPV6_VRRP, TRAP_TO_CPU, ROUTER_EXP, false),
 	/* PKT Sample trap */
 	MLXSW_RXL(mlxsw_sp_rx_listener_sample_func, PKT_SAMPLE, MIRROR_TO_CPU,
 		  false, SP_IP2ME, DISCARD),
@@ -4420,7 +4422,8 @@ static int mlxsw_sp_netdevice_port_upper_event(struct net_device *lower_dev,
 		if (!is_vlan_dev(upper_dev) &&
 		    !netif_is_lag_master(upper_dev) &&
 		    !netif_is_bridge_master(upper_dev) &&
-		    !netif_is_ovs_master(upper_dev)) {
+		    !netif_is_ovs_master(upper_dev) &&
+		    !netif_is_macvlan(upper_dev)) {
 			NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
 			return -EINVAL;
 		}
@@ -4446,6 +4449,11 @@ static int mlxsw_sp_netdevice_port_upper_event(struct net_device *lower_dev,
 			NL_SET_ERR_MSG_MOD(extack, "Can not put a VLAN on a LAG port");
 			return -EINVAL;
 		}
+		if (netif_is_macvlan(upper_dev) &&
+		    !mlxsw_sp_rif_find_by_dev(mlxsw_sp, lower_dev)) {
+			NL_SET_ERR_MSG_MOD(extack, "macvlan is only supported on top of router interfaces");
+			return -EOPNOTSUPP;
+		}
 		if (netif_is_ovs_master(upper_dev) && vlan_uses_dev(dev)) {
 			NL_SET_ERR_MSG_MOD(extack, "Master device is an OVS master and this device has a VLAN");
 			return -EINVAL;
@@ -4484,6 +4492,9 @@ static int mlxsw_sp_netdevice_port_upper_event(struct net_device *lower_dev,
 				err = mlxsw_sp_port_ovs_join(mlxsw_sp_port);
 			else
 				mlxsw_sp_port_ovs_leave(mlxsw_sp_port);
+		} else if (netif_is_macvlan(upper_dev)) {
+			if (!info->linking)
+				mlxsw_sp_rif_macvlan_del(mlxsw_sp, upper_dev);
 		}
 		break;
 	}
@@ -4568,8 +4579,9 @@ static int mlxsw_sp_netdevice_port_vlan_event(struct net_device *vlan_dev,
 	switch (event) {
 	case NETDEV_PRECHANGEUPPER:
 		upper_dev = info->upper_dev;
-		if (!netif_is_bridge_master(upper_dev)) {
-			NL_SET_ERR_MSG_MOD(extack, "VLAN devices only support bridge and VRF uppers");
+		if (!netif_is_bridge_master(upper_dev) &&
+		    !netif_is_macvlan(upper_dev)) {
+			NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
 			return -EINVAL;
 		}
 		if (!info->linking)
@@ -4581,6 +4593,11 @@ static int mlxsw_sp_netdevice_port_vlan_event(struct net_device *vlan_dev,
 			NL_SET_ERR_MSG_MOD(extack, "Enslaving a port to a device that already has an upper device is not supported");
 			return -EINVAL;
 		}
+		if (netif_is_macvlan(upper_dev) &&
+		    !mlxsw_sp_rif_find_by_dev(mlxsw_sp, vlan_dev)) {
+			NL_SET_ERR_MSG_MOD(extack, "macvlan is only supported on top of router interfaces");
+			return -EOPNOTSUPP;
+		}
 		break;
 	case NETDEV_CHANGEUPPER:
 		upper_dev = info->upper_dev;
@@ -4594,6 +4611,9 @@ static int mlxsw_sp_netdevice_port_vlan_event(struct net_device *vlan_dev,
 				mlxsw_sp_port_bridge_leave(mlxsw_sp_port,
 							   vlan_dev,
 							   upper_dev);
+		} else if (netif_is_macvlan(upper_dev)) {
+			if (!info->linking)
+				mlxsw_sp_rif_macvlan_del(mlxsw_sp, upper_dev);
 		} else {
 			err = -EINVAL;
 			WARN_ON(1);
@@ -4643,6 +4663,64 @@ static int mlxsw_sp_netdevice_vlan_event(struct net_device *vlan_dev,
 	return 0;
 }
 
+static int mlxsw_sp_netdevice_bridge_event(struct net_device *br_dev,
+					   unsigned long event, void *ptr)
+{
+	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_lower_get(br_dev);
+	struct netdev_notifier_changeupper_info *info = ptr;
+	struct netlink_ext_ack *extack;
+	struct net_device *upper_dev;
+
+	if (!mlxsw_sp)
+		return 0;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	switch (event) {
+	case NETDEV_PRECHANGEUPPER:
+		upper_dev = info->upper_dev;
+		if (!is_vlan_dev(upper_dev) && !netif_is_macvlan(upper_dev)) {
+			NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
+			return -EOPNOTSUPP;
+		}
+		if (!info->linking)
+			break;
+		if (netif_is_macvlan(upper_dev) &&
+		    !mlxsw_sp_rif_find_by_dev(mlxsw_sp, br_dev)) {
+			NL_SET_ERR_MSG_MOD(extack, "macvlan is only supported on top of router interfaces");
+			return -EOPNOTSUPP;
+		}
+		break;
+	case NETDEV_CHANGEUPPER:
+		upper_dev = info->upper_dev;
+		if (info->linking)
+			break;
+		if (netif_is_macvlan(upper_dev))
+			mlxsw_sp_rif_macvlan_del(mlxsw_sp, upper_dev);
+		break;
+	}
+
+	return 0;
+}
+
+static int mlxsw_sp_netdevice_macvlan_event(struct net_device *macvlan_dev,
+					    unsigned long event, void *ptr)
+{
+	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_lower_get(macvlan_dev);
+	struct netdev_notifier_changeupper_info *info = ptr;
+	struct netlink_ext_ack *extack;
+
+	if (!mlxsw_sp || event != NETDEV_PRECHANGEUPPER)
+		return 0;
+
+	extack = netdev_notifier_info_to_extack(&info->info);
+
+	/* VRF enslavement is handled in mlxsw_sp_netdevice_vrf_event() */
+	NL_SET_ERR_MSG_MOD(extack, "Unknown upper device type");
+
+	return -EOPNOTSUPP;
+}
+
 static bool mlxsw_sp_is_vrf_event(unsigned long event, void *ptr)
 {
 	struct netdev_notifier_changeupper_info *info = ptr;
@@ -4684,6 +4762,10 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *nb,
 		err = mlxsw_sp_netdevice_lag_event(dev, event, ptr);
 	else if (is_vlan_dev(dev))
 		err = mlxsw_sp_netdevice_vlan_event(dev, event, ptr);
+	else if (netif_is_bridge_master(dev))
+		err = mlxsw_sp_netdevice_bridge_event(dev, event, ptr);
+	else if (netif_is_macvlan(dev))
+		err = mlxsw_sp_netdevice_macvlan_event(dev, event, ptr);
 
 	return notifier_from_errno(err);
 }

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -417,6 +417,8 @@ static inline void mlxsw_sp_port_dcb_fini(struct mlxsw_sp_port *mlxsw_sp_port)
 int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp);
 void mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp);
 int mlxsw_sp_netdevice_router_port_event(struct net_device *dev);
+void mlxsw_sp_rif_macvlan_del(struct mlxsw_sp *mlxsw_sp,
+			      const struct net_device *macvlan_dev);
 int mlxsw_sp_inetaddr_event(struct notifier_block *unused,
 			    unsigned long event, void *ptr);
 int mlxsw_sp_inetaddr_valid_event(struct notifier_block *unused,