Quelle  goto.c   Sprache: C

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

#include "act.h"
#include "en/tc_priv.h"
#include "eswitch.h"

static int
validate_goto_chain(struct mlx5e_priv *priv,
      struct mlx5e_tc_flow *flow,
      struct mlx5_flow_attr *attr,
      const struct flow_action_entry *act,
      struct netlink_ext_ack *extack)
{
 struct mlx5e_tc_table *tc = mlx5e_fs_get_tc(priv->fs);
 bool is_esw = mlx5e_is_eswitch_flow(flow);
 bool ft_flow = mlx5e_is_ft_flow(flow);
 u32 dest_chain = act->chain_index;
 struct mlx5_fs_chains *chains;
 struct mlx5_eswitch *esw;
 u32 reformat_and_fwd;
 u32 max_chain;

 esw = priv->mdev->priv.eswitch;
 chains = is_esw ? esw_chains(esw) : mlx5e_nic_chains(tc);
 max_chain = mlx5_chains_get_chain_range(chains);
 reformat_and_fwd = is_esw ?
      MLX5_CAP_ESW_FLOWTABLE_FDB(priv->mdev, reformat_and_fwd_to_table) :
      MLX5_CAP_FLOWTABLE_NIC_RX(priv->mdev, reformat_and_fwd_to_table);

 if (ft_flow) {
  NL_SET_ERR_MSG_MOD(extack, "Goto action is not supported");
  return -EOPNOTSUPP;
 }

 if (!mlx5_chains_backwards_supported(chains) &&
     dest_chain <= attr->chain) {
  NL_SET_ERR_MSG_MOD(extack, "Goto lower numbered chain isn't supported");
  return -EOPNOTSUPP;
 }

 if (dest_chain > max_chain) {
  NL_SET_ERR_MSG_MOD(extack,
       "Requested destination chain is out of supported range");
  return -EOPNOTSUPP;
 }

 if (attr->action & (MLX5_FLOW_CONTEXT_ACTION_PACKET_REFORMAT |
       MLX5_FLOW_CONTEXT_ACTION_DECAP) &&
     !reformat_and_fwd) {
  NL_SET_ERR_MSG_MOD(extack,
       "Goto chain is not allowed if action has reformat or decap");
  return -EOPNOTSUPP;
 }

 return 0;
}

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

 if (validate_goto_chain(flow->priv, flow, attr, act, extack))
  return false;

 return true;
}

static int
tc_act_parse_goto(struct mlx5e_tc_act_parse_state *parse_state,
    const struct flow_action_entry *act,
    struct mlx5e_priv *priv,
    struct mlx5_flow_attr *attr)
{
 attr->action |= MLX5_FLOW_CONTEXT_ACTION_FWD_DEST;
 attr->dest_chain = act->chain_index;

 return 0;
}

static int
tc_act_post_parse_goto(struct mlx5e_tc_act_parse_state *parse_state,
         struct mlx5e_priv *priv,
         struct mlx5_flow_attr *attr)
{
 struct mlx5e_tc_flow_parse_attr *parse_attr = attr->parse_attr;
 struct netlink_ext_ack *extack = parse_state->extack;
 struct mlx5e_tc_flow *flow = parse_state->flow;

 if (!attr->dest_chain)
  return 0;

 if (parse_state->decap) {
  /* It can be supported if we'll create a mapping for
 * the tunnel device only (without tunnel), and set
 * this tunnel id with this decap flow.
 *
 * On restore (miss), we'll just set this saved tunnel
 * device.
 */

  NL_SET_ERR_MSG_MOD(extack, "Decap with goto isn't supported");
  netdev_warn(priv->netdev, "Decap with goto isn't supported");
  return -EOPNOTSUPP;
 }

 if (!mlx5e_is_eswitch_flow(flow) && parse_attr->mirred_ifindex[0]) {
  NL_SET_ERR_MSG_MOD(extack, "Mirroring goto chain rules isn't supported");
  return -EOPNOTSUPP;
 }

 return 0;
}

struct mlx5e_tc_act mlx5e_tc_act_goto = {
 .can_offload = tc_act_can_offload_goto,
 .parse_action = tc_act_parse_goto,
 .post_parse = tc_act_post_parse_goto,
 .is_terminating_action = true,
};