[PATCH net-next 5/7] mlxsw: Offload trap_fwd

[Petr Machata <petrm@nvidia.com>]

Offload the TC action trap_fwd. This is offloaded as a TRAP_ACTION with
forward_action of FORWARD (as opposed to NOP for the trap action). Unlike
trap, trap_fwd needs to be in an "goto"-typed action set, not "next"-typed
one.

Trap_fwd'd traffic is marked with offload_fwd_mark and offload_l3_fwd_mark
to prevent second forwarding in the SW datapath.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
---
 .../mellanox/mlxsw/core_acl_flex_actions.c    | 23 +++++++++++++++----
 .../net/ethernet/mellanox/mlxsw/spectrum.h    |  1 +
 .../ethernet/mellanox/mlxsw/spectrum_acl.c    |  6 +++++
 .../ethernet/mellanox/mlxsw/spectrum_flower.c |  7 ++++++
 .../ethernet/mellanox/mlxsw/spectrum_trap.c   |  8 +++++++
 drivers/net/ethernet/mellanox/mlxsw/trap.h    |  2 ++
 6 files changed, 43 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c b/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
index faa90cc31376..d7d7e688139f 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
@@ -94,7 +94,8 @@ struct mlxsw_afa_set {
 		      * kvdl_index is valid).
 		      */
 	   has_trap:1,
-	   has_police:1;
+	   has_police:1,
+	   has_trap_fwd:1;
 	unsigned int ref_count;
 	struct mlxsw_afa_set *next; /* Pointer to the next set. */
 	struct mlxsw_afa_set *prev; /* Pointer to the previous set,
@@ -263,14 +264,23 @@ static void mlxsw_afa_set_goto_set(struct mlxsw_afa_set *set,
 	mlxsw_afa_set_goto_next_binding_set(actions, group_id);
 }
 
-static void mlxsw_afa_set_next_set(struct mlxsw_afa_set *set,
+static int mlxsw_afa_set_next_set(struct mlxsw_afa_set *set,
 				  u32 next_set_kvdl_index,
 				  struct netlink_ext_ack *extack)
 {
 	char *actions = set->ht_key.enc_actions;
 
+	/* If the forwarding action is not drop, the next/goto record must not
+	 * be a next, it must be a goto.
+	 */
+	if (set->has_trap_fwd) {
+		NL_SET_ERR_MSG_MOD(extack, "Only goto permissible after a trap_fwd action");
+		return -EINVAL;
+	}
+
 	mlxsw_afa_set_type_set(actions, MLXSW_AFA_SET_TYPE_NEXT);
 	mlxsw_afa_set_next_action_set_ptr_set(actions, next_set_kvdl_index);
+	return 0;
 }
 
 static struct mlxsw_afa_set *mlxsw_afa_set_create(bool is_first)
@@ -461,6 +471,7 @@ int mlxsw_afa_block_commit(struct mlxsw_afa_block *block,
 {
 	struct mlxsw_afa_set *set = block->cur_set;
 	struct mlxsw_afa_set *prev_set;
+	int err;
 
 	block->cur_set = NULL;
 	block->finished = true;
@@ -481,8 +492,10 @@ int mlxsw_afa_block_commit(struct mlxsw_afa_block *block,
 			return PTR_ERR(set);
 		if (prev_set) {
 			prev_set->next = set;
-			mlxsw_afa_set_next_set(prev_set, set->kvdl_index,
-					       extack);
+			err = mlxsw_afa_set_next_set(prev_set, set->kvdl_index,
+						     extack);
+			if (err)
+				return err;
 			set = prev_set;
 		}
 	} while (prev_set);
@@ -1346,6 +1359,8 @@ int mlxsw_afa_block_append_trap_and_forward(struct mlxsw_afa_block *block,
 
 	if (IS_ERR(act))
 		return PTR_ERR(act);
+
+	block->cur_set->has_trap_fwd = true;
 	mlxsw_afa_trap_pack(act, MLXSW_AFA_TRAP_TRAP_ACTION_TRAP,
 			    MLXSW_AFA_TRAP_FORWARD_ACTION_FORWARD, trap_id);
 	return 0;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index d74fc7ff8083..6067a049dcf2 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -940,6 +940,7 @@ int mlxsw_sp_acl_rulei_act_drop(struct mlxsw_sp_acl_rule_info *rulei,
 				const struct flow_action_cookie *fa_cookie,
 				struct netlink_ext_ack *extack);
 int mlxsw_sp_acl_rulei_act_trap(struct mlxsw_sp_acl_rule_info *rulei);
+int mlxsw_sp_acl_rulei_act_trap_fwd(struct mlxsw_sp_acl_rule_info *rulei);
 int mlxsw_sp_acl_rulei_act_mirror(struct mlxsw_sp *mlxsw_sp,
 				  struct mlxsw_sp_acl_rule_info *rulei,
 				  struct mlxsw_sp_flow_block *block,
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
index b9c4c1feba6d..6f7913424bd9 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
@@ -401,6 +401,12 @@ int mlxsw_sp_acl_rulei_act_trap(struct mlxsw_sp_acl_rule_info *rulei)
 					   MLXSW_TRAP_ID_ACL0);
 }
 
+int mlxsw_sp_acl_rulei_act_trap_fwd(struct mlxsw_sp_acl_rule_info *rulei)
+{
+	return mlxsw_afa_block_append_trap_and_forward(rulei->act_block,
+						       MLXSW_TRAP_ID_ACL3);
+}
+
 int mlxsw_sp_acl_rulei_act_fwd(struct mlxsw_sp *mlxsw_sp,
 			       struct mlxsw_sp_acl_rule_info *rulei,
 			       struct net_device *out_dev,
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
index 936788f741dd..1f52ea7ba202 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
@@ -86,6 +86,13 @@ static int mlxsw_sp_flower_parse_actions(struct mlxsw_sp *mlxsw_sp,
 				return err;
 			}
 			break;
+		case FLOW_ACTION_TRAP_FWD:
+			err = mlxsw_sp_acl_rulei_act_trap_fwd(rulei);
+			if (err) {
+				NL_SET_ERR_MSG_MOD(extack, "Cannot append trap_fwd action");
+				return err;
+			}
+			break;
 		case FLOW_ACTION_GOTO: {
 			u32 chain_index = act->chain_index;
 			struct mlxsw_sp_acl_ruleset *ruleset;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c
index 26d01adbedad..504fb7440a1f 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_trap.c
@@ -1154,6 +1154,14 @@ static const struct mlxsw_sp_trap_item mlxsw_sp_trap_items_arr[] = {
 					     false),
 		},
 	},
+	{
+		.trap = MLXSW_SP_TRAP_CONTROL(FLOW_ACTION_TRAP_FWD,
+					      ACL_TRAP, MIRROR),
+		.listeners_arr = {
+			MLXSW_SP_RXL_L3_MARK(ACL3, FLOW_LOGGING, MIRROR_TO_CPU,
+					     false),
+		},
+	},
 	{
 		.trap = MLXSW_SP_TRAP_DROP(BLACKHOLE_NEXTHOP, L3_DROPS),
 		.listeners_arr = {
diff --git a/drivers/net/ethernet/mellanox/mlxsw/trap.h b/drivers/net/ethernet/mellanox/mlxsw/trap.h
index 9e070ab3ed76..5271d7ad092a 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/trap.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/trap.h
@@ -108,6 +108,8 @@ enum {
 	MLXSW_TRAP_ID_ACL2 = 0x1C2,
 	MLXSW_TRAP_ID_DISCARD_INGRESS_ACL = 0x1C3,
 	MLXSW_TRAP_ID_DISCARD_EGRESS_ACL = 0x1C4,
+	/* Packets trapped due to FLOW_ACTION_TRAP_FWD. */
+	MLXSW_TRAP_ID_ACL3 = 0x1C5,
 	MLXSW_TRAP_ID_MIRROR_SESSION0 = 0x220,
 	MLXSW_TRAP_ID_MIRROR_SESSION1 = 0x221,
 	MLXSW_TRAP_ID_MIRROR_SESSION2 = 0x222,
-- 
2.26.2