Merge branch 'mlxsw-ecn-marking'

Ido Schimmel says:

====================
mlxsw: spectrum: Fix ECN marking in tunnel decapsulation

Patch #1 fixes a discrepancy between the software and hardware data
paths with regards to ECN marking after decapsulation. See the changelog
for a detailed description.

Patch #2 extends the ECN decap test to cover all possible combinations
of inner and outer ECN markings. The test passes over both data paths.

v2:
* Only set ECT(1) if inner is ECT(0)
* Introduce a new helper to determine inner ECN. Share it between NVE
  and IP-in-IP tunnels
* Extend the selftest
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -21,6 +21,7 @@
 #include <net/red.h>
 #include <net/vxlan.h>
 #include <net/flow_offload.h>
+#include <net/inet_ecn.h>
 
 #include "port.h"
 #include "core.h"
@@ -347,6 +348,20 @@ struct mlxsw_sp_port_type_speed_ops {
 	u32 (*ptys_proto_cap_masked_get)(u32 eth_proto_cap);
 };
 
+static inline u8 mlxsw_sp_tunnel_ecn_decap(u8 outer_ecn, u8 inner_ecn,
+					   bool *trap_en)
+{
+	bool set_ce = false;
+
+	*trap_en = !!__INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce);
+	if (set_ce)
+		return INET_ECN_CE;
+	else if (outer_ecn == INET_ECN_ECT_1 && inner_ecn == INET_ECN_ECT_0)
+		return INET_ECN_ECT_1;
+	else
+		return inner_ecn;
+}
+
 static inline struct net_device *
 mlxsw_sp_bridge_vxlan_dev_find(struct net_device *br_dev)
 {

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

@@ -335,12 +335,11 @@ static int mlxsw_sp_ipip_ecn_decap_init_one(struct mlxsw_sp *mlxsw_sp,
 					    u8 inner_ecn, u8 outer_ecn)
 {
 	char tidem_pl[MLXSW_REG_TIDEM_LEN];
-	bool trap_en, set_ce = false;
 	u8 new_inner_ecn;
+	bool trap_en;
 
-	trap_en = __INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce);
-	new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn;
-
+	new_inner_ecn = mlxsw_sp_tunnel_ecn_decap(outer_ecn, inner_ecn,
+						  &trap_en);
 	mlxsw_reg_tidem_pack(tidem_pl, outer_ecn, inner_ecn, new_inner_ecn,
 			     trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);
 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tidem), tidem_pl);

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

@@ -909,12 +909,11 @@ static int __mlxsw_sp_nve_ecn_decap_init(struct mlxsw_sp *mlxsw_sp,
 					 u8 inner_ecn, u8 outer_ecn)
 {
 	char tndem_pl[MLXSW_REG_TNDEM_LEN];
-	bool trap_en, set_ce = false;
 	u8 new_inner_ecn;
+	bool trap_en;
 
-	trap_en = !!__INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce);
-	new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn;
-
+	new_inner_ecn = mlxsw_sp_tunnel_ecn_decap(outer_ecn, inner_ecn,
+						  &trap_en);
 	mlxsw_reg_tndem_pack(tndem_pl, outer_ecn, inner_ecn, new_inner_ecn,
 			     trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);
 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tndem), tndem_pl);

tools/testing/selftests/net/forwarding/vxlan_bridge_1d.sh

@@ -657,10 +657,21 @@ test_ecn_decap()
 {
 	# In accordance with INET_ECN_decapsulate()
 	__test_ecn_decap 00 00 0x00
+	__test_ecn_decap 00 01 0x00
+	__test_ecn_decap 00 02 0x00
+	# 00 03 is tested in test_ecn_decap_error()
+	__test_ecn_decap 01 00 0x01
 	__test_ecn_decap 01 01 0x01
-	__test_ecn_decap 02 01 0x01
+	__test_ecn_decap 01 02 0x01
 	__test_ecn_decap 01 03 0x03
+	__test_ecn_decap 02 00 0x02
+	__test_ecn_decap 02 01 0x01
+	__test_ecn_decap 02 02 0x02
 	__test_ecn_decap 02 03 0x03
+	__test_ecn_decap 03 00 0x03
+	__test_ecn_decap 03 01 0x03
+	__test_ecn_decap 03 02 0x03
+	__test_ecn_decap 03 03 0x03
 	test_ecn_decap_error
 }