// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
// Copyright (c) 2021, NVIDIA CORPORATION & AFFILIATES. All rights reserved.

#include <linux/tc_act/tc_csum.h>
#include "act.h"
#include "en/tc_priv.h"

static bool
csum_offload_supported(struct mlx5e_priv *priv,
                       u32 action,
                       u32 update_flags,
                       struct netlink_ext_ack *extack)
{
        u32 prot_flags = TCA_CSUM_UPDATE_FLAG_IPV4HDR | TCA_CSUM_UPDATE_FLAG_TCP |
                         TCA_CSUM_UPDATE_FLAG_UDP;

        /*  The HW recalcs checksums only if re-writing headers */
        if (!(action & MLX5_FLOW_CONTEXT_ACTION_MOD_HDR)) {
                NL_SET_ERR_MSG_MOD(extack,
                                   "TC csum action is only offloaded with pedit");
                netdev_warn(priv->netdev,
                            "TC csum action is only offloaded with pedit\n");
                return false;
        }

        if (update_flags & ~prot_flags) {
                NL_SET_ERR_MSG_MOD(extack,
                                   "can't offload TC csum action for some header/s");
                netdev_warn(priv->netdev,
                            "can't offload TC csum action for some header/s - flags %#x\n",
                            update_flags);
                return false;
        }

        return true;
}

static bool
tc_act_can_offload_csum(struct mlx5e_tc_act_parse_state *parse_state,
                        const struct flow_action_entry *act,
                        int act_index,
                        struct mlx5_flow_attr *attr)
{
        struct mlx5e_tc_flow *flow = parse_state->flow;

        return csum_offload_supported(flow->priv, attr->action,
                                      act->csum_flags, parse_state->extack);
}

static int
tc_act_parse_csum(struct mlx5e_tc_act_parse_state *parse_state,
                  const struct flow_action_entry *act,
                  struct mlx5e_priv *priv,
                  struct mlx5_flow_attr *attr)
{
        return 0;
}

struct mlx5e_tc_act mlx5e_tc_act_csum = {
        .can_offload = tc_act_can_offload_csum,
        .parse_action = tc_act_parse_csum,
};