net: bridge: Add support for offloading port attributes

Currently the flood, learning and learning_sync port attributes are
offloaded by setting the SELF flag. Add support for offloading the
flood and learning attribute through the bridge code. In case of
setting an unsupported flag on a offloded port the operation will
fail.

The learning_sync attribute doesn't have any software representation
and cannot be offloaded through the bridge code.
Signed-off-by: Arkadi Sharshevsky <arkadis@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_netlink.c

@@ -662,16 +662,26 @@ static int br_set_port_state(struct net_bridge_port *p, u8 state)
 }
 
 /* Set/clear or port flags based on attribute */
-static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
+static int br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[],
 			    int attrtype, unsigned long mask)
 {
-	if (tb[attrtype]) {
-		u8 flag = nla_get_u8(tb[attrtype]);
-		if (flag)
-			p->flags |= mask;
+	unsigned long flags;
+	int err;
+
+	if (!tb[attrtype])
+		return 0;
+
+	if (nla_get_u8(tb[attrtype]))
+		flags = p->flags | mask;
 	else
-			p->flags &= ~mask;
-	}
+		flags = p->flags & ~mask;
+
+	err = br_switchdev_set_port_flag(p, flags, mask);
+	if (err)
+		return err;
+
+	p->flags = flags;
+	return 0;
 }
 
 /* Process bridge protocol info on port */
@@ -681,20 +691,55 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[])
 	bool br_vlan_tunnel_old = false;
 	int err;
 
-	br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
-	br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
-	br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE);
-	br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
-	br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
-	br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
-	br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_FLOOD, BR_MCAST_FLOOD);
-	br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_TO_UCAST, BR_MULTICAST_TO_UNICAST);
-	br_set_port_flag(p, tb, IFLA_BRPORT_BCAST_FLOOD, BR_BCAST_FLOOD);
-	br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP);
-	br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP_WIFI, BR_PROXYARP_WIFI);
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_PROTECT, BR_ROOT_BLOCK);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_LEARNING, BR_LEARNING);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_UNICAST_FLOOD, BR_FLOOD);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_FLOOD, BR_MCAST_FLOOD);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_MCAST_TO_UCAST, BR_MULTICAST_TO_UNICAST);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_BCAST_FLOOD, BR_BCAST_FLOOD);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP, BR_PROXYARP);
+	if (err)
+		return err;
+
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_PROXYARP_WIFI, BR_PROXYARP_WIFI);
+	if (err)
+		return err;
 
 	br_vlan_tunnel_old = (p->flags & BR_VLAN_TUNNEL) ? true : false;
-	br_set_port_flag(p, tb, IFLA_BRPORT_VLAN_TUNNEL, BR_VLAN_TUNNEL);
+	err = br_set_port_flag(p, tb, IFLA_BRPORT_VLAN_TUNNEL, BR_VLAN_TUNNEL);
+	if (err)
+		return err;
+
 	if (br_vlan_tunnel_old && !(p->flags & BR_VLAN_TUNNEL))
 		nbp_vlan_tunnel_info_flush(p);
 

net/bridge/br_private.h

@@ -1076,6 +1076,9 @@ void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 			      struct sk_buff *skb);
 bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
 				  const struct sk_buff *skb);
+int br_switchdev_set_port_flag(struct net_bridge_port *p,
+			       unsigned long flags,
+			       unsigned long mask);
 #else
 static inline int nbp_switchdev_mark_set(struct net_bridge_port *p)
 {
@@ -1092,6 +1095,13 @@ static inline bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
 {
 	return true;
 }
+
+static inline int br_switchdev_set_port_flag(struct net_bridge_port *p,
+					     unsigned long flags,
+					     unsigned long mask)
+{
+	return 0;
+}
 #endif /* CONFIG_NET_SWITCHDEV */
 
 #endif

net/bridge/br_switchdev.c

@@ -55,3 +55,46 @@ bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
 	return !skb->offload_fwd_mark ||
 	       BR_INPUT_SKB_CB(skb)->offload_fwd_mark != p->offload_fwd_mark;
 }
+
+/* Flags that can be offloaded to hardware */
+#define BR_PORT_FLAGS_HW_OFFLOAD (BR_LEARNING | BR_FLOOD | \
+				  BR_MCAST_FLOOD | BR_BCAST_FLOOD)
+
+int br_switchdev_set_port_flag(struct net_bridge_port *p,
+			       unsigned long flags,
+			       unsigned long mask)
+{
+	struct switchdev_attr attr = {
+		.orig_dev = p->dev,
+		.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS_SUPPORT,
+	};
+	int err;
+
+	if (mask & ~BR_PORT_FLAGS_HW_OFFLOAD)
+		return 0;
+
+	err = switchdev_port_attr_get(p->dev, &attr);
+	if (err == -EOPNOTSUPP)
+		return 0;
+	if (err)
+		return err;
+
+	/* Check if specific bridge flag attribute offload is supported */
+	if (!(attr.u.brport_flags_support & mask)) {
+		br_warn(p->br, "bridge flag offload is not supported %u(%s)\n",
+			(unsigned int)p->port_no, p->dev->name);
+		return -EOPNOTSUPP;
+	}
+
+	attr.id = SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS;
+	attr.flags = SWITCHDEV_F_DEFER;
+	attr.u.brport_flags = flags;
+	err = switchdev_port_attr_set(p->dev, &attr);
+	if (err) {
+		br_warn(p->br, "error setting offload flag on port %u(%s)\n",
+			(unsigned int)p->port_no, p->dev->name);
+		return err;
+	}
+
+	return 0;
+}