xref: /linux/drivers/net/ethernet/mellanox/mlxsw/spectrum_ipip.c (revision 48dea9a700c8728cc31a1dd44588b97578de86ee)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /* Copyright (c) 2017-2018 Mellanox Technologies. All rights reserved */
3 
4 #include <net/ip_tunnels.h>
5 #include <net/ip6_tunnel.h>
6 #include <net/inet_ecn.h>
7 
8 #include "spectrum_ipip.h"
9 #include "reg.h"
10 
11 struct ip_tunnel_parm
12 mlxsw_sp_ipip_netdev_parms4(const struct net_device *ol_dev)
13 {
14 	struct ip_tunnel *tun = netdev_priv(ol_dev);
15 
16 	return tun->parms;
17 }
18 
19 struct __ip6_tnl_parm
20 mlxsw_sp_ipip_netdev_parms6(const struct net_device *ol_dev)
21 {
22 	struct ip6_tnl *tun = netdev_priv(ol_dev);
23 
24 	return tun->parms;
25 }
26 
27 static bool mlxsw_sp_ipip_parms4_has_ikey(struct ip_tunnel_parm parms)
28 {
29 	return !!(parms.i_flags & TUNNEL_KEY);
30 }
31 
32 static bool mlxsw_sp_ipip_parms4_has_okey(struct ip_tunnel_parm parms)
33 {
34 	return !!(parms.o_flags & TUNNEL_KEY);
35 }
36 
37 static u32 mlxsw_sp_ipip_parms4_ikey(struct ip_tunnel_parm parms)
38 {
39 	return mlxsw_sp_ipip_parms4_has_ikey(parms) ?
40 		be32_to_cpu(parms.i_key) : 0;
41 }
42 
43 static u32 mlxsw_sp_ipip_parms4_okey(struct ip_tunnel_parm parms)
44 {
45 	return mlxsw_sp_ipip_parms4_has_okey(parms) ?
46 		be32_to_cpu(parms.o_key) : 0;
47 }
48 
49 static union mlxsw_sp_l3addr
50 mlxsw_sp_ipip_parms4_saddr(struct ip_tunnel_parm parms)
51 {
52 	return (union mlxsw_sp_l3addr) { .addr4 = parms.iph.saddr };
53 }
54 
55 static union mlxsw_sp_l3addr
56 mlxsw_sp_ipip_parms6_saddr(struct __ip6_tnl_parm parms)
57 {
58 	return (union mlxsw_sp_l3addr) { .addr6 = parms.laddr };
59 }
60 
61 static union mlxsw_sp_l3addr
62 mlxsw_sp_ipip_parms4_daddr(struct ip_tunnel_parm parms)
63 {
64 	return (union mlxsw_sp_l3addr) { .addr4 = parms.iph.daddr };
65 }
66 
67 static union mlxsw_sp_l3addr
68 mlxsw_sp_ipip_parms6_daddr(struct __ip6_tnl_parm parms)
69 {
70 	return (union mlxsw_sp_l3addr) { .addr6 = parms.raddr };
71 }
72 
73 union mlxsw_sp_l3addr
74 mlxsw_sp_ipip_netdev_saddr(enum mlxsw_sp_l3proto proto,
75 			   const struct net_device *ol_dev)
76 {
77 	struct ip_tunnel_parm parms4;
78 	struct __ip6_tnl_parm parms6;
79 
80 	switch (proto) {
81 	case MLXSW_SP_L3_PROTO_IPV4:
82 		parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
83 		return mlxsw_sp_ipip_parms4_saddr(parms4);
84 	case MLXSW_SP_L3_PROTO_IPV6:
85 		parms6 = mlxsw_sp_ipip_netdev_parms6(ol_dev);
86 		return mlxsw_sp_ipip_parms6_saddr(parms6);
87 	}
88 
89 	WARN_ON(1);
90 	return (union mlxsw_sp_l3addr) {0};
91 }
92 
93 static __be32 mlxsw_sp_ipip_netdev_daddr4(const struct net_device *ol_dev)
94 {
95 
96 	struct ip_tunnel_parm parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
97 
98 	return mlxsw_sp_ipip_parms4_daddr(parms4).addr4;
99 }
100 
101 static union mlxsw_sp_l3addr
102 mlxsw_sp_ipip_netdev_daddr(enum mlxsw_sp_l3proto proto,
103 			   const struct net_device *ol_dev)
104 {
105 	struct ip_tunnel_parm parms4;
106 	struct __ip6_tnl_parm parms6;
107 
108 	switch (proto) {
109 	case MLXSW_SP_L3_PROTO_IPV4:
110 		parms4 = mlxsw_sp_ipip_netdev_parms4(ol_dev);
111 		return mlxsw_sp_ipip_parms4_daddr(parms4);
112 	case MLXSW_SP_L3_PROTO_IPV6:
113 		parms6 = mlxsw_sp_ipip_netdev_parms6(ol_dev);
114 		return mlxsw_sp_ipip_parms6_daddr(parms6);
115 	}
116 
117 	WARN_ON(1);
118 	return (union mlxsw_sp_l3addr) {0};
119 }
120 
121 bool mlxsw_sp_l3addr_is_zero(union mlxsw_sp_l3addr addr)
122 {
123 	union mlxsw_sp_l3addr naddr = {0};
124 
125 	return !memcmp(&addr, &naddr, sizeof(naddr));
126 }
127 
128 static int
129 mlxsw_sp_ipip_nexthop_update_gre4(struct mlxsw_sp *mlxsw_sp, u32 adj_index,
130 				  struct mlxsw_sp_ipip_entry *ipip_entry)
131 {
132 	u16 rif_index = mlxsw_sp_ipip_lb_rif_index(ipip_entry->ol_lb);
133 	__be32 daddr4 = mlxsw_sp_ipip_netdev_daddr4(ipip_entry->ol_dev);
134 	char ratr_pl[MLXSW_REG_RATR_LEN];
135 
136 	mlxsw_reg_ratr_pack(ratr_pl, MLXSW_REG_RATR_OP_WRITE_WRITE_ENTRY,
137 			    true, MLXSW_REG_RATR_TYPE_IPIP,
138 			    adj_index, rif_index);
139 	mlxsw_reg_ratr_ipip4_entry_pack(ratr_pl, be32_to_cpu(daddr4));
140 
141 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ratr), ratr_pl);
142 }
143 
144 static int
145 mlxsw_sp_ipip_fib_entry_op_gre4_rtdp(struct mlxsw_sp *mlxsw_sp,
146 				     u32 tunnel_index,
147 				     struct mlxsw_sp_ipip_entry *ipip_entry)
148 {
149 	u16 rif_index = mlxsw_sp_ipip_lb_rif_index(ipip_entry->ol_lb);
150 	u16 ul_rif_id = mlxsw_sp_ipip_lb_ul_rif_id(ipip_entry->ol_lb);
151 	char rtdp_pl[MLXSW_REG_RTDP_LEN];
152 	struct ip_tunnel_parm parms;
153 	unsigned int type_check;
154 	bool has_ikey;
155 	u32 daddr4;
156 	u32 ikey;
157 
158 	parms = mlxsw_sp_ipip_netdev_parms4(ipip_entry->ol_dev);
159 	has_ikey = mlxsw_sp_ipip_parms4_has_ikey(parms);
160 	ikey = mlxsw_sp_ipip_parms4_ikey(parms);
161 
162 	mlxsw_reg_rtdp_pack(rtdp_pl, MLXSW_REG_RTDP_TYPE_IPIP, tunnel_index);
163 	mlxsw_reg_rtdp_egress_router_interface_set(rtdp_pl, ul_rif_id);
164 
165 	type_check = has_ikey ?
166 		MLXSW_REG_RTDP_IPIP_TYPE_CHECK_ALLOW_GRE_KEY :
167 		MLXSW_REG_RTDP_IPIP_TYPE_CHECK_ALLOW_GRE;
168 
169 	/* Linux demuxes tunnels based on packet SIP (which must match tunnel
170 	 * remote IP). Thus configure decap so that it filters out packets that
171 	 * are not IPv4 or have the wrong SIP. IPIP_DECAP_ERROR trap is
172 	 * generated for packets that fail this criterion. Linux then handles
173 	 * such packets in slow path and generates ICMP destination unreachable.
174 	 */
175 	daddr4 = be32_to_cpu(mlxsw_sp_ipip_netdev_daddr4(ipip_entry->ol_dev));
176 	mlxsw_reg_rtdp_ipip4_pack(rtdp_pl, rif_index,
177 				  MLXSW_REG_RTDP_IPIP_SIP_CHECK_FILTER_IPV4,
178 				  type_check, has_ikey, daddr4, ikey);
179 
180 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(rtdp), rtdp_pl);
181 }
182 
183 static int
184 mlxsw_sp_ipip_fib_entry_op_gre4_ralue(struct mlxsw_sp *mlxsw_sp,
185 				      u32 dip, u8 prefix_len, u16 ul_vr_id,
186 				      enum mlxsw_reg_ralue_op op,
187 				      u32 tunnel_index)
188 {
189 	char ralue_pl[MLXSW_REG_RALUE_LEN];
190 
191 	mlxsw_reg_ralue_pack4(ralue_pl, MLXSW_REG_RALXX_PROTOCOL_IPV4, op,
192 			      ul_vr_id, prefix_len, dip);
193 	mlxsw_reg_ralue_act_ip2me_tun_pack(ralue_pl, tunnel_index);
194 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ralue), ralue_pl);
195 }
196 
197 static int mlxsw_sp_ipip_fib_entry_op_gre4(struct mlxsw_sp *mlxsw_sp,
198 					struct mlxsw_sp_ipip_entry *ipip_entry,
199 					enum mlxsw_reg_ralue_op op,
200 					u32 tunnel_index)
201 {
202 	u16 ul_vr_id = mlxsw_sp_ipip_lb_ul_vr_id(ipip_entry->ol_lb);
203 	__be32 dip;
204 	int err;
205 
206 	err = mlxsw_sp_ipip_fib_entry_op_gre4_rtdp(mlxsw_sp, tunnel_index,
207 						   ipip_entry);
208 	if (err)
209 		return err;
210 
211 	dip = mlxsw_sp_ipip_netdev_saddr(MLXSW_SP_L3_PROTO_IPV4,
212 					 ipip_entry->ol_dev).addr4;
213 	return mlxsw_sp_ipip_fib_entry_op_gre4_ralue(mlxsw_sp, be32_to_cpu(dip),
214 						     32, ul_vr_id, op,
215 						     tunnel_index);
216 }
217 
218 static bool mlxsw_sp_ipip_tunnel_complete(enum mlxsw_sp_l3proto proto,
219 					  const struct net_device *ol_dev)
220 {
221 	union mlxsw_sp_l3addr saddr = mlxsw_sp_ipip_netdev_saddr(proto, ol_dev);
222 	union mlxsw_sp_l3addr daddr = mlxsw_sp_ipip_netdev_daddr(proto, ol_dev);
223 
224 	/* Tunnels with unset local or remote address are valid in Linux and
225 	 * used for lightweight tunnels (LWT) and Non-Broadcast Multi-Access
226 	 * (NBMA) tunnels. In principle these can be offloaded, but the driver
227 	 * currently doesn't support this. So punt.
228 	 */
229 	return !mlxsw_sp_l3addr_is_zero(saddr) &&
230 	       !mlxsw_sp_l3addr_is_zero(daddr);
231 }
232 
233 static bool mlxsw_sp_ipip_can_offload_gre4(const struct mlxsw_sp *mlxsw_sp,
234 					   const struct net_device *ol_dev,
235 					   enum mlxsw_sp_l3proto ol_proto)
236 {
237 	struct ip_tunnel *tunnel = netdev_priv(ol_dev);
238 	__be16 okflags = TUNNEL_KEY; /* We can't offload any other features. */
239 	bool inherit_ttl = tunnel->parms.iph.ttl == 0;
240 	bool inherit_tos = tunnel->parms.iph.tos & 0x1;
241 
242 	return (tunnel->parms.i_flags & ~okflags) == 0 &&
243 	       (tunnel->parms.o_flags & ~okflags) == 0 &&
244 	       inherit_ttl && inherit_tos &&
245 	       mlxsw_sp_ipip_tunnel_complete(MLXSW_SP_L3_PROTO_IPV4, ol_dev);
246 }
247 
248 static struct mlxsw_sp_rif_ipip_lb_config
249 mlxsw_sp_ipip_ol_loopback_config_gre4(struct mlxsw_sp *mlxsw_sp,
250 				      const struct net_device *ol_dev)
251 {
252 	struct ip_tunnel_parm parms = mlxsw_sp_ipip_netdev_parms4(ol_dev);
253 	enum mlxsw_reg_ritr_loopback_ipip_type lb_ipipt;
254 
255 	lb_ipipt = mlxsw_sp_ipip_parms4_has_okey(parms) ?
256 		MLXSW_REG_RITR_LOOPBACK_IPIP_TYPE_IP_IN_GRE_KEY_IN_IP :
257 		MLXSW_REG_RITR_LOOPBACK_IPIP_TYPE_IP_IN_GRE_IN_IP;
258 	return (struct mlxsw_sp_rif_ipip_lb_config){
259 		.lb_ipipt = lb_ipipt,
260 		.okey = mlxsw_sp_ipip_parms4_okey(parms),
261 		.ul_protocol = MLXSW_SP_L3_PROTO_IPV4,
262 		.saddr = mlxsw_sp_ipip_netdev_saddr(MLXSW_SP_L3_PROTO_IPV4,
263 						    ol_dev),
264 	};
265 }
266 
267 static int
268 mlxsw_sp_ipip_ol_netdev_change_gre4(struct mlxsw_sp *mlxsw_sp,
269 				    struct mlxsw_sp_ipip_entry *ipip_entry,
270 				    struct netlink_ext_ack *extack)
271 {
272 	union mlxsw_sp_l3addr old_saddr, new_saddr;
273 	union mlxsw_sp_l3addr old_daddr, new_daddr;
274 	struct ip_tunnel_parm new_parms;
275 	bool update_tunnel = false;
276 	bool update_decap = false;
277 	bool update_nhs = false;
278 	int err = 0;
279 
280 	new_parms = mlxsw_sp_ipip_netdev_parms4(ipip_entry->ol_dev);
281 
282 	new_saddr = mlxsw_sp_ipip_parms4_saddr(new_parms);
283 	old_saddr = mlxsw_sp_ipip_parms4_saddr(ipip_entry->parms4);
284 	new_daddr = mlxsw_sp_ipip_parms4_daddr(new_parms);
285 	old_daddr = mlxsw_sp_ipip_parms4_daddr(ipip_entry->parms4);
286 
287 	if (!mlxsw_sp_l3addr_eq(&new_saddr, &old_saddr)) {
288 		u16 ul_tb_id = mlxsw_sp_ipip_dev_ul_tb_id(ipip_entry->ol_dev);
289 
290 		/* Since the local address has changed, if there is another
291 		 * tunnel with a matching saddr, both need to be demoted.
292 		 */
293 		if (mlxsw_sp_ipip_demote_tunnel_by_saddr(mlxsw_sp,
294 							 MLXSW_SP_L3_PROTO_IPV4,
295 							 new_saddr, ul_tb_id,
296 							 ipip_entry)) {
297 			mlxsw_sp_ipip_entry_demote_tunnel(mlxsw_sp, ipip_entry);
298 			return 0;
299 		}
300 
301 		update_tunnel = true;
302 	} else if ((mlxsw_sp_ipip_parms4_okey(ipip_entry->parms4) !=
303 		    mlxsw_sp_ipip_parms4_okey(new_parms)) ||
304 		   ipip_entry->parms4.link != new_parms.link) {
305 		update_tunnel = true;
306 	} else if (!mlxsw_sp_l3addr_eq(&new_daddr, &old_daddr)) {
307 		update_nhs = true;
308 	} else if (mlxsw_sp_ipip_parms4_ikey(ipip_entry->parms4) !=
309 		   mlxsw_sp_ipip_parms4_ikey(new_parms)) {
310 		update_decap = true;
311 	}
312 
313 	if (update_tunnel)
314 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
315 							  true, true, true,
316 							  extack);
317 	else if (update_nhs)
318 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
319 							  false, false, true,
320 							  extack);
321 	else if (update_decap)
322 		err = __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
323 							  false, false, false,
324 							  extack);
325 
326 	ipip_entry->parms4 = new_parms;
327 	return err;
328 }
329 
330 static const struct mlxsw_sp_ipip_ops mlxsw_sp_ipip_gre4_ops = {
331 	.dev_type = ARPHRD_IPGRE,
332 	.ul_proto = MLXSW_SP_L3_PROTO_IPV4,
333 	.nexthop_update = mlxsw_sp_ipip_nexthop_update_gre4,
334 	.fib_entry_op = mlxsw_sp_ipip_fib_entry_op_gre4,
335 	.can_offload = mlxsw_sp_ipip_can_offload_gre4,
336 	.ol_loopback_config = mlxsw_sp_ipip_ol_loopback_config_gre4,
337 	.ol_netdev_change = mlxsw_sp_ipip_ol_netdev_change_gre4,
338 };
339 
340 const struct mlxsw_sp_ipip_ops *mlxsw_sp_ipip_ops_arr[] = {
341 	[MLXSW_SP_IPIP_TYPE_GRE4] = &mlxsw_sp_ipip_gre4_ops,
342 };
343 
344 static int mlxsw_sp_ipip_ecn_encap_init_one(struct mlxsw_sp *mlxsw_sp,
345 					    u8 inner_ecn, u8 outer_ecn)
346 {
347 	char tieem_pl[MLXSW_REG_TIEEM_LEN];
348 
349 	mlxsw_reg_tieem_pack(tieem_pl, inner_ecn, outer_ecn);
350 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tieem), tieem_pl);
351 }
352 
353 int mlxsw_sp_ipip_ecn_encap_init(struct mlxsw_sp *mlxsw_sp)
354 {
355 	int i;
356 
357 	/* Iterate over inner ECN values */
358 	for (i = INET_ECN_NOT_ECT; i <= INET_ECN_CE; i++) {
359 		u8 outer_ecn = INET_ECN_encapsulate(0, i);
360 		int err;
361 
362 		err = mlxsw_sp_ipip_ecn_encap_init_one(mlxsw_sp, i, outer_ecn);
363 		if (err)
364 			return err;
365 	}
366 
367 	return 0;
368 }
369 
370 static int mlxsw_sp_ipip_ecn_decap_init_one(struct mlxsw_sp *mlxsw_sp,
371 					    u8 inner_ecn, u8 outer_ecn)
372 {
373 	char tidem_pl[MLXSW_REG_TIDEM_LEN];
374 	bool trap_en, set_ce = false;
375 	u8 new_inner_ecn;
376 
377 	trap_en = __INET_ECN_decapsulate(outer_ecn, inner_ecn, &set_ce);
378 	new_inner_ecn = set_ce ? INET_ECN_CE : inner_ecn;
379 
380 	mlxsw_reg_tidem_pack(tidem_pl, outer_ecn, inner_ecn, new_inner_ecn,
381 			     trap_en, trap_en ? MLXSW_TRAP_ID_DECAP_ECN0 : 0);
382 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(tidem), tidem_pl);
383 }
384 
385 int mlxsw_sp_ipip_ecn_decap_init(struct mlxsw_sp *mlxsw_sp)
386 {
387 	int i, j, err;
388 
389 	/* Iterate over inner ECN values */
390 	for (i = INET_ECN_NOT_ECT; i <= INET_ECN_CE; i++) {
391 		/* Iterate over outer ECN values */
392 		for (j = INET_ECN_NOT_ECT; j <= INET_ECN_CE; j++) {
393 			err = mlxsw_sp_ipip_ecn_decap_init_one(mlxsw_sp, i, j);
394 			if (err)
395 				return err;
396 		}
397 	}
398 
399 	return 0;
400 }
401