From: Ido Schimmel <idosch@mellanox.com>
Date: Sat, 14 Jul 2018 11:39:54 +0300
Subject: mlxsw: spectrum_router: Optimize processing of VRRP MACs
Patch-mainline: v4.19-rc1
Git-commit: c3a495409adeb677fa8b53f4cfe37cf9cfb7c751
References: bsc#1112374

Hosts using a VRRP router send their packets with a destination MAC of
the VRRP router which is of the following form [1]:

IPv4 - 00-00-5E-00-01-{VRID}
IPv6 - 00-00-5E-00-02-{VRID}

Where VRID is the ID of the virtual router. Such packets are directed to
the router block in the ASIC by an FDB entry that was added in the
previous patch.

However, in certain cases it is possible to skip this FDB lookup and
send such packets directly to the router. This is accomplished by adding
these special MAC addresses to the RIF cache. If the cache is hit, the
packet will skip the L2 lookup and ingress the router with the RIF
specified in the cache entry.

1. https://tools.ietf.org/html/rfc5798#section-7.3

Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlxsw/reg.h             |   14 ++++
 drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c |   52 ++++++++++++++++++
 2 files changed, 66 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlxsw/reg.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/reg.h
@@ -4353,6 +4353,20 @@ MLXSW_ITEM32(reg, ritr, if_swid, 0x08, 2
  */
 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
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -6445,6 +6445,46 @@ static int mlxsw_sp_inetaddr_vlan_event(
 	return 0;
 }
 
+static bool mlxsw_sp_rif_macvlan_is_vrrp4(const u8 *mac)
+{
+	u8 vrrp4[ETH_ALEN] = { 0x00, 0x00, 0x5e, 0x00, 0x01, 0x00 };
+	u8 mask[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0x00 };
+
+	return ether_addr_equal_masked(mac, vrrp4, mask);
+}
+
+static bool mlxsw_sp_rif_macvlan_is_vrrp6(const u8 *mac)
+{
+	u8 vrrp6[ETH_ALEN] = { 0x00, 0x00, 0x5e, 0x00, 0x02, 0x00 };
+	u8 mask[ETH_ALEN] = { 0xff, 0xff, 0xff, 0xff, 0xff, 0x00 };
+
+	return ether_addr_equal_masked(mac, vrrp6, mask);
+}
+
+static int mlxsw_sp_rif_vrrp_op(struct mlxsw_sp *mlxsw_sp, u16 rif_index,
+				const u8 *mac, bool adding)
+{
+	char ritr_pl[MLXSW_REG_RITR_LEN];
+	u8 vrrp_id = adding ? mac[5] : 0;
+	int err;
+
+	if (!mlxsw_sp_rif_macvlan_is_vrrp4(mac) &&
+	    !mlxsw_sp_rif_macvlan_is_vrrp6(mac))
+		return 0;
+
+	mlxsw_reg_ritr_rif_pack(ritr_pl, rif_index);
+	err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(ritr), ritr_pl);
+	if (err)
+		return err;
+
+	if (mlxsw_sp_rif_macvlan_is_vrrp4(mac))
+		mlxsw_reg_ritr_if_vrrp_id_ipv4_set(ritr_pl, vrrp_id);
+	else
+		mlxsw_reg_ritr_if_vrrp_id_ipv6_set(ritr_pl, vrrp_id);
+
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ritr), ritr_pl);
+}
+
 static int mlxsw_sp_rif_macvlan_add(struct mlxsw_sp *mlxsw_sp,
 				    const struct net_device *macvlan_dev,
 				    struct netlink_ext_ack *extack)
@@ -6464,6 +6504,11 @@ static int mlxsw_sp_rif_macvlan_add(stru
 	if (err)
 		return err;
 
+	err = mlxsw_sp_rif_vrrp_op(mlxsw_sp, rif->rif_index,
+				   macvlan_dev->dev_addr, true);
+	if (err)
+		goto err_rif_vrrp_add;
+
 	/* Make sure the bridge driver does not have this MAC pointing at
 	 * some other port.
 	 */
@@ -6471,6 +6516,11 @@ static int mlxsw_sp_rif_macvlan_add(stru
 		rif->ops->fdb_del(rif, macvlan_dev->dev_addr);
 
 	return 0;
+
+err_rif_vrrp_add:
+	mlxsw_sp_rif_fdb_op(mlxsw_sp, macvlan_dev->dev_addr,
+			    mlxsw_sp_fid_index(rif->fid), false);
+	return err;
 }
 
 void mlxsw_sp_rif_macvlan_del(struct mlxsw_sp *mlxsw_sp,
@@ -6485,6 +6535,8 @@ void mlxsw_sp_rif_macvlan_del(struct mlx
 	 */
 	if (!rif)
 		return;
+	mlxsw_sp_rif_vrrp_op(mlxsw_sp, rif->rif_index, macvlan_dev->dev_addr,
+			     false);
 	mlxsw_sp_rif_fdb_op(mlxsw_sp, macvlan_dev->dev_addr,
 			    mlxsw_sp_fid_index(rif->fid), false);
 }