tc_tun_gre.c

  1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
  2/* Copyright (c) 2018 Mellanox Technologies. */
  3
  4#include <net/gre.h>
  5#include "en/tc_tun.h"
  6
  7static bool mlx5e_tc_tun_can_offload_gretap(struct mlx5e_priv *priv)
  8{
  9	return !!MLX5_CAP_ESW(priv->mdev, nvgre_encap_decap);
 10}
 11
 12static int mlx5e_tc_tun_calc_hlen_gretap(struct mlx5e_encap_entry *e)
 13{
 14	return gre_calc_hlen(e->tun_info->key.tun_flags);
 15}
 16
 17static int mlx5e_tc_tun_init_encap_attr_gretap(struct net_device *tunnel_dev,
 18					       struct mlx5e_priv *priv,
 19					       struct mlx5e_encap_entry *e,
 20					       struct netlink_ext_ack *extack)
 21{
 22	e->tunnel = &gre_tunnel;
 23	e->reformat_type = MLX5_REFORMAT_TYPE_L2_TO_NVGRE;
 24	return 0;
 25}
 26
 27static int mlx5e_gen_ip_tunnel_header_gretap(char buf[],
 28					     __u8 *ip_proto,
 29					     struct mlx5e_encap_entry *e)
 30{
 31	const struct ip_tunnel_key *tun_key  = &e->tun_info->key;
 32	struct gre_base_hdr *greh = (struct gre_base_hdr *)(buf);
 33	__be32 tun_id = tunnel_id_to_key32(tun_key->tun_id);
 34	IP_TUNNEL_DECLARE_FLAGS(unsupp) = { };
 35	int hdr_len;
 36
 37	*ip_proto = IPPROTO_GRE;
 38
 39	/* the HW does not calculate GRE csum or sequences */
 40	__set_bit(IP_TUNNEL_CSUM_BIT, unsupp);
 41	__set_bit(IP_TUNNEL_SEQ_BIT, unsupp);
 42
 43	if (ip_tunnel_flags_intersect(tun_key->tun_flags, unsupp))
 44		return -EOPNOTSUPP;
 45
 46	greh->protocol = htons(ETH_P_TEB);
 47
 48	/* GRE key */
 49	hdr_len	= mlx5e_tc_tun_calc_hlen_gretap(e);
 50	greh->flags = gre_tnl_flags_to_gre_flags(tun_key->tun_flags);
 51	if (test_bit(IP_TUNNEL_KEY_BIT, tun_key->tun_flags)) {
 52		__be32 *ptr = (__be32 *)(((u8 *)greh) + hdr_len - 4);
 53		*ptr = tun_id;
 54	}
 55
 56	return 0;
 57}
 58
 59static int mlx5e_tc_tun_parse_gretap(struct mlx5e_priv *priv,
 60				     struct mlx5_flow_spec *spec,
 61				     struct flow_cls_offload *f,
 62				     void *headers_c,
 63				     void *headers_v)
 64{
 65	void *misc_c = MLX5_ADDR_OF(fte_match_param, spec->match_criteria, misc_parameters);
 66	void *misc_v = MLX5_ADDR_OF(fte_match_param, spec->match_value, misc_parameters);
 67	struct flow_rule *rule = flow_cls_offload_flow_rule(f);
 68
 69	MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, headers_c, ip_protocol);
 70	MLX5_SET(fte_match_set_lyr_2_4, headers_v, ip_protocol, IPPROTO_GRE);
 71
 72	/* gre protocol */
 73	MLX5_SET_TO_ONES(fte_match_set_misc, misc_c, gre_protocol);
 74	MLX5_SET(fte_match_set_misc, misc_v, gre_protocol, ETH_P_TEB);
 75
 76	/* gre key */
 77	if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
 78		struct flow_match_enc_keyid enc_keyid;
 79
 80		flow_rule_match_enc_keyid(rule, &enc_keyid);
 81		MLX5_SET(fte_match_set_misc, misc_c,
 82			 gre_key.key, be32_to_cpu(enc_keyid.mask->keyid));
 83		MLX5_SET(fte_match_set_misc, misc_v,
 84			 gre_key.key, be32_to_cpu(enc_keyid.key->keyid));
 85	}
 86
 87	spec->match_criteria_enable |= MLX5_MATCH_MISC_PARAMETERS;
 88
 89	return 0;
 90}
 91
 92struct mlx5e_tc_tunnel gre_tunnel = {
 93	.tunnel_type          = MLX5E_TC_TUNNEL_TYPE_GRETAP,
 94	.match_level          = MLX5_MATCH_L3,
 95	.can_offload          = mlx5e_tc_tun_can_offload_gretap,
 96	.calc_hlen            = mlx5e_tc_tun_calc_hlen_gretap,
 97	.init_encap_attr      = mlx5e_tc_tun_init_encap_attr_gretap,
 98	.generate_ip_tun_hdr  = mlx5e_gen_ip_tunnel_header_gretap,
 99	.parse_udp_ports      = NULL,
100	.parse_tunnel         = mlx5e_tc_tun_parse_gretap,
101	.encap_info_equal     = mlx5e_tc_tun_encap_info_equal_generic,
102};