net/mlx5e: Don't overwrite pedit action when multiple pedit used

In some case, we may use multiple pedit actions to modify packets.
The command shown as below: the last pedit action is effective.

$ tc filter add dev netdev_rep parent ffff: protocol ip prio 1    \
	flower skip_sw ip_proto icmp dst_ip 3.3.3.3        \
	action pedit ex munge ip dst set 192.168.1.100 pipe    \
	action pedit ex munge eth src set 00:00:00:00:00:01 pipe    \
	action pedit ex munge eth dst set 00:00:00:00:00:02 pipe    \
	action csum ip pipe    \
	action tunnel_key set src_ip 1.1.1.100 dst_ip 1.1.1.200 dst_port 4789 id 100 \
	action mirred egress redirect dev vxlan0

To fix it, we add max_mod_hdr_actions to mlx5e_tc_flow_parse_attr struction,
max_mod_hdr_actions will store the max pedit action number we support and
num_mod_hdr_actions indicates how many pedit action we used, and store all
pedit action to mod_hdr_actions.

Fixes: d79b6df ("net/mlx5e: Add parsing of TC pedit actions to HW format")
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -128,6 +128,7 @@ struct mlx5e_tc_flow_parse_attr {
 	struct net_device *filter_dev;
 	struct mlx5_flow_spec spec;
 	int num_mod_hdr_actions;
+	int max_mod_hdr_actions;
 	void *mod_hdr_actions;
 	int mirred_ifindex[MLX5_MAX_FLOW_FWD_VPORTS];
 };
@@ -1936,9 +1937,9 @@ static struct mlx5_fields fields[] = {
 	OFFLOAD(UDP_DPORT, 2, udp.dest,   0),
 };
 
-/* On input attr->num_mod_hdr_actions tells how many HW actions can be parsed at
- * max from the SW pedit action. On success, it says how many HW actions were
- * actually parsed.
+/* On input attr->max_mod_hdr_actions tells how many HW actions can be parsed at
+ * max from the SW pedit action. On success, attr->num_mod_hdr_actions
+ * says how many HW actions were actually parsed.
  */
 static int offload_pedit_fields(struct pedit_headers *masks,
 				struct pedit_headers *vals,
@@ -1962,9 +1963,11 @@ static int offload_pedit_fields(struct pedit_headers *masks,
 	add_vals = &vals[TCA_PEDIT_KEY_EX_CMD_ADD];
 
 	action_size = MLX5_UN_SZ_BYTES(set_action_in_add_action_in_auto);
-	action = parse_attr->mod_hdr_actions;
-	max_actions = parse_attr->num_mod_hdr_actions;
-	nactions = 0;
+	action = parse_attr->mod_hdr_actions +
+		 parse_attr->num_mod_hdr_actions * action_size;
+
+	max_actions = parse_attr->max_mod_hdr_actions;
+	nactions = parse_attr->num_mod_hdr_actions;
 
 	for (i = 0; i < ARRAY_SIZE(fields); i++) {
 		f = &fields[i];
@@ -2075,7 +2078,7 @@ static int alloc_mod_hdr_actions(struct mlx5e_priv *priv,
 	if (!parse_attr->mod_hdr_actions)
 		return -ENOMEM;
 
-	parse_attr->num_mod_hdr_actions = max_actions;
+	parse_attr->max_mod_hdr_actions = max_actions;
 	return 0;
 }
 
@@ -2121,9 +2124,11 @@ static int parse_tc_pedit_action(struct mlx5e_priv *priv,
 			goto out_err;
 	}
 
-	err = alloc_mod_hdr_actions(priv, a, namespace, parse_attr);
-	if (err)
-		goto out_err;
+	if (!parse_attr->mod_hdr_actions) {
+		err = alloc_mod_hdr_actions(priv, a, namespace, parse_attr);
+		if (err)
+			goto out_err;
+	}
 
 	err = offload_pedit_fields(masks, vals, parse_attr, extack);
 	if (err < 0)