[PATCH net-next v2 2/2] net/mlx5e: Don't overwrite pedit action when multiple pedit used

[xiangxia . m . yue]

From: Tonghao Zhang <xiangxia.m....@gmail.com>

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.

Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_tc.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index cae6c6d..2ee377a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/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];
 };
@@ -1960,8 +1961,9 @@ 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;
+       action = parse_attr->mod_hdr_actions +
+               parse_attr->num_mod_hdr_actions * action_size;
+       max_actions = parse_attr->max_mod_hdr_actions;
        nactions = 0;
 
        for (i = 0; i < ARRAY_SIZE(fields); i++) {
@@ -2048,7 +2050,7 @@ static int offload_pedit_fields(struct pedit_headers 
*masks,
                nactions++;
        }
 
-       parse_attr->num_mod_hdr_actions = nactions;
+       parse_attr->num_mod_hdr_actions += nactions;
        return 0;
 }
 
@@ -2073,7 +2075,8 @@ 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;
+       parse_attr->num_mod_hdr_actions = 0;
        return 0;
 }
 
@@ -2119,9 +2122,11 @@ 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)
-- 
1.8.3.1