xref: /linux/drivers/net/ethernet/sfc/tc_encap_actions.c (revision 91ec2035134982b98fab0609a9fd8480e8217dc1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2023, Advanced Micro Devices, Inc.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation, incorporated herein by reference.
9  */
10 
11 #include "tc_encap_actions.h"
12 #include "tc.h"
13 #include "mae.h"
14 #include <net/flow.h>
15 #include <net/inet_dscp.h>
16 #include <net/vxlan.h>
17 #include <net/geneve.h>
18 #include <net/netevent.h>
19 #include <net/arp.h>
20 
21 static const struct rhashtable_params efx_neigh_ht_params = {
22 	.key_len	= offsetof(struct efx_neigh_binder, ha),
23 	.key_offset	= 0,
24 	.head_offset	= offsetof(struct efx_neigh_binder, linkage),
25 };
26 
27 static const struct rhashtable_params efx_tc_encap_ht_params = {
28 	.key_len	= offsetofend(struct efx_tc_encap_action, key),
29 	.key_offset	= 0,
30 	.head_offset	= offsetof(struct efx_tc_encap_action, linkage),
31 };
32 
efx_tc_encap_free(void * ptr,void * __unused)33 static void efx_tc_encap_free(void *ptr, void *__unused)
34 {
35 	struct efx_tc_encap_action *enc = ptr;
36 
37 	WARN_ON(refcount_read(&enc->ref));
38 	kfree(enc);
39 }
40 
efx_neigh_free(void * ptr,void * __unused)41 static void efx_neigh_free(void *ptr, void *__unused)
42 {
43 	struct efx_neigh_binder *neigh = ptr;
44 
45 	WARN_ON(refcount_read(&neigh->ref));
46 	WARN_ON(!list_empty(&neigh->users));
47 	put_net_track(neigh->net, &neigh->ns_tracker);
48 	netdev_put(neigh->egdev, &neigh->dev_tracker);
49 	kfree(neigh);
50 }
51 
efx_tc_init_encap_actions(struct efx_nic * efx)52 int efx_tc_init_encap_actions(struct efx_nic *efx)
53 {
54 	int rc;
55 
56 	rc = rhashtable_init(&efx->tc->neigh_ht, &efx_neigh_ht_params);
57 	if (rc < 0)
58 		goto fail_neigh_ht;
59 	rc = rhashtable_init(&efx->tc->encap_ht, &efx_tc_encap_ht_params);
60 	if (rc < 0)
61 		goto fail_encap_ht;
62 	return 0;
63 fail_encap_ht:
64 	rhashtable_destroy(&efx->tc->neigh_ht);
65 fail_neigh_ht:
66 	return rc;
67 }
68 
69 /* Only call this in init failure teardown.
70  * Normal exit should fini instead as there may be entries in the table.
71  */
efx_tc_destroy_encap_actions(struct efx_nic * efx)72 void efx_tc_destroy_encap_actions(struct efx_nic *efx)
73 {
74 	rhashtable_destroy(&efx->tc->encap_ht);
75 	rhashtable_destroy(&efx->tc->neigh_ht);
76 }
77 
efx_tc_fini_encap_actions(struct efx_nic * efx)78 void efx_tc_fini_encap_actions(struct efx_nic *efx)
79 {
80 	rhashtable_free_and_destroy(&efx->tc->encap_ht, efx_tc_encap_free, NULL);
81 	rhashtable_free_and_destroy(&efx->tc->neigh_ht, efx_neigh_free, NULL);
82 }
83 
84 static void efx_neigh_update(struct work_struct *work);
85 
efx_bind_neigh(struct efx_nic * efx,struct efx_tc_encap_action * encap,struct net * net,struct netlink_ext_ack * extack)86 static int efx_bind_neigh(struct efx_nic *efx,
87 			  struct efx_tc_encap_action *encap, struct net *net,
88 			  struct netlink_ext_ack *extack)
89 {
90 	struct efx_neigh_binder *neigh, *old;
91 	struct flowi6 flow6 = {};
92 	struct flowi4 flow4 = {};
93 	int rc;
94 
95 	/* GCC stupidly thinks that only values explicitly listed in the enum
96 	 * definition can _possibly_ be sensible case values, so without this
97 	 * cast it complains about the IPv6 versions.
98 	 */
99 	switch ((int)encap->type) {
100 	case EFX_ENCAP_TYPE_VXLAN:
101 	case EFX_ENCAP_TYPE_GENEVE:
102 		flow4.flowi4_proto = IPPROTO_UDP;
103 		flow4.fl4_dport = encap->key.tp_dst;
104 		flow4.flowi4_dscp = inet_dsfield_to_dscp(encap->key.tos);
105 		flow4.daddr = encap->key.u.ipv4.dst;
106 		flow4.saddr = encap->key.u.ipv4.src;
107 		break;
108 	case EFX_ENCAP_TYPE_VXLAN | EFX_ENCAP_FLAG_IPV6:
109 	case EFX_ENCAP_TYPE_GENEVE | EFX_ENCAP_FLAG_IPV6:
110 		flow6.flowi6_proto = IPPROTO_UDP;
111 		flow6.fl6_dport = encap->key.tp_dst;
112 		flow6.flowlabel = ip6_make_flowinfo(encap->key.tos,
113 						    encap->key.label);
114 		flow6.daddr = encap->key.u.ipv6.dst;
115 		flow6.saddr = encap->key.u.ipv6.src;
116 		break;
117 	default:
118 		NL_SET_ERR_MSG_FMT_MOD(extack, "Unsupported encap type %d",
119 				       (int)encap->type);
120 		return -EOPNOTSUPP;
121 	}
122 
123 	neigh = kzalloc_obj(*neigh, GFP_KERNEL_ACCOUNT);
124 	if (!neigh)
125 		return -ENOMEM;
126 	neigh->net = get_net_track(net, &neigh->ns_tracker, GFP_KERNEL_ACCOUNT);
127 	neigh->dst_ip = flow4.daddr;
128 	neigh->dst_ip6 = flow6.daddr;
129 
130 	old = rhashtable_lookup_get_insert_fast(&efx->tc->neigh_ht,
131 						&neigh->linkage,
132 						efx_neigh_ht_params);
133 	if (old) {
134 		/* don't need our new entry */
135 		put_net_track(neigh->net, &neigh->ns_tracker);
136 		kfree(neigh);
137 		if (IS_ERR(old)) /* oh dear, it's actually an error */
138 			return PTR_ERR(old);
139 		if (!refcount_inc_not_zero(&old->ref))
140 			return -EAGAIN;
141 		/* existing entry found, ref taken */
142 		neigh = old;
143 	} else {
144 		/* New entry.  We need to initiate a lookup */
145 		struct neighbour *n;
146 		struct rtable *rt;
147 
148 		if (encap->type & EFX_ENCAP_FLAG_IPV6) {
149 #if IS_ENABLED(CONFIG_IPV6)
150 			struct dst_entry *dst;
151 
152 			dst = ip6_dst_lookup_flow(net, NULL, &flow6, NULL);
153 			rc = PTR_ERR_OR_ZERO(dst);
154 			if (rc) {
155 				NL_SET_ERR_MSG_MOD(extack, "Failed to lookup route for IPv6 encap");
156 				goto out_free;
157 			}
158 			neigh->egdev = dst->dev;
159 			netdev_hold(neigh->egdev, &neigh->dev_tracker,
160 				    GFP_KERNEL_ACCOUNT);
161 			neigh->ttl = ip6_dst_hoplimit(dst);
162 			n = dst_neigh_lookup(dst, &flow6.daddr);
163 			dst_release(dst);
164 #else
165 			/* We shouldn't ever get here, because if IPv6 isn't
166 			 * enabled how did someone create an IPv6 tunnel_key?
167 			 */
168 			rc = -EOPNOTSUPP;
169 			NL_SET_ERR_MSG_MOD(extack, "No IPv6 support (neigh bind)");
170 			goto out_free;
171 #endif
172 		} else {
173 			rt = ip_route_output_key(net, &flow4);
174 			if (IS_ERR_OR_NULL(rt)) {
175 				rc = PTR_ERR_OR_ZERO(rt);
176 				if (!rc)
177 					rc = -EIO;
178 				NL_SET_ERR_MSG_MOD(extack, "Failed to lookup route for encap");
179 				goto out_free;
180 			}
181 			neigh->egdev = rt->dst.dev;
182 			netdev_hold(neigh->egdev, &neigh->dev_tracker,
183 				    GFP_KERNEL_ACCOUNT);
184 			neigh->ttl = ip4_dst_hoplimit(&rt->dst);
185 			n = dst_neigh_lookup(&rt->dst, &flow4.daddr);
186 			ip_rt_put(rt);
187 		}
188 		if (!n) {
189 			rc = -ENETUNREACH;
190 			NL_SET_ERR_MSG_MOD(extack, "Failed to lookup neighbour for encap");
191 			netdev_put(neigh->egdev, &neigh->dev_tracker);
192 			goto out_free;
193 		}
194 		refcount_set(&neigh->ref, 1);
195 		INIT_LIST_HEAD(&neigh->users);
196 		read_lock_bh(&n->lock);
197 		ether_addr_copy(neigh->ha, n->ha);
198 		neigh->n_valid = n->nud_state & NUD_VALID;
199 		read_unlock_bh(&n->lock);
200 		rwlock_init(&neigh->lock);
201 		INIT_WORK(&neigh->work, efx_neigh_update);
202 		neigh->efx = efx;
203 		neigh->used = jiffies;
204 		if (!neigh->n_valid)
205 			/* Prod ARP to find us a neighbour */
206 			neigh_event_send(n, NULL);
207 		neigh_release(n);
208 	}
209 	/* Add us to this neigh */
210 	encap->neigh = neigh;
211 	list_add_tail(&encap->list, &neigh->users);
212 	return 0;
213 
214 out_free:
215 	/* cleanup common to several error paths */
216 	rhashtable_remove_fast(&efx->tc->neigh_ht, &neigh->linkage,
217 			       efx_neigh_ht_params);
218 	synchronize_rcu();
219 	put_net_track(net, &neigh->ns_tracker);
220 	kfree(neigh);
221 	return rc;
222 }
223 
efx_free_neigh(struct efx_neigh_binder * neigh)224 static void efx_free_neigh(struct efx_neigh_binder *neigh)
225 {
226 	struct efx_nic *efx = neigh->efx;
227 
228 	rhashtable_remove_fast(&efx->tc->neigh_ht, &neigh->linkage,
229 			       efx_neigh_ht_params);
230 	synchronize_rcu();
231 	netdev_put(neigh->egdev, &neigh->dev_tracker);
232 	put_net_track(neigh->net, &neigh->ns_tracker);
233 	kfree(neigh);
234 }
235 
efx_release_neigh(struct efx_nic * efx,struct efx_tc_encap_action * encap)236 static void efx_release_neigh(struct efx_nic *efx,
237 			      struct efx_tc_encap_action *encap)
238 {
239 	struct efx_neigh_binder *neigh = encap->neigh;
240 
241 	if (!neigh)
242 		return;
243 	list_del(&encap->list);
244 	encap->neigh = NULL;
245 	if (!refcount_dec_and_test(&neigh->ref))
246 		return; /* still in use */
247 	efx_free_neigh(neigh);
248 }
249 
efx_gen_tun_header_eth(struct efx_tc_encap_action * encap,u16 proto)250 static void efx_gen_tun_header_eth(struct efx_tc_encap_action *encap, u16 proto)
251 {
252 	struct efx_neigh_binder *neigh = encap->neigh;
253 	struct ethhdr *eth;
254 
255 	encap->encap_hdr_len = sizeof(*eth);
256 	eth = (struct ethhdr *)encap->encap_hdr;
257 
258 	if (encap->neigh->n_valid)
259 		ether_addr_copy(eth->h_dest, neigh->ha);
260 	else
261 		eth_zero_addr(eth->h_dest);
262 	ether_addr_copy(eth->h_source, neigh->egdev->dev_addr);
263 	eth->h_proto = htons(proto);
264 }
265 
efx_gen_tun_header_ipv4(struct efx_tc_encap_action * encap,u8 ipproto,u8 len)266 static void efx_gen_tun_header_ipv4(struct efx_tc_encap_action *encap, u8 ipproto, u8 len)
267 {
268 	struct efx_neigh_binder *neigh = encap->neigh;
269 	struct ip_tunnel_key *key = &encap->key;
270 	struct iphdr *ip;
271 
272 	ip = (struct iphdr *)(encap->encap_hdr + encap->encap_hdr_len);
273 	encap->encap_hdr_len += sizeof(*ip);
274 
275 	ip->daddr = key->u.ipv4.dst;
276 	ip->saddr = key->u.ipv4.src;
277 	ip->ttl = neigh->ttl;
278 	ip->protocol = ipproto;
279 	ip->version = 0x4;
280 	ip->ihl = 0x5;
281 	ip->tot_len = cpu_to_be16(ip->ihl * 4 + len);
282 	ip_send_check(ip);
283 }
284 
285 #ifdef CONFIG_IPV6
efx_gen_tun_header_ipv6(struct efx_tc_encap_action * encap,u8 ipproto,u8 len)286 static void efx_gen_tun_header_ipv6(struct efx_tc_encap_action *encap, u8 ipproto, u8 len)
287 {
288 	struct efx_neigh_binder *neigh = encap->neigh;
289 	struct ip_tunnel_key *key = &encap->key;
290 	struct ipv6hdr *ip;
291 
292 	ip = (struct ipv6hdr *)(encap->encap_hdr + encap->encap_hdr_len);
293 	encap->encap_hdr_len += sizeof(*ip);
294 
295 	ip6_flow_hdr(ip, key->tos, key->label);
296 	ip->daddr = key->u.ipv6.dst;
297 	ip->saddr = key->u.ipv6.src;
298 	ip->hop_limit = neigh->ttl;
299 	ip->nexthdr = ipproto;
300 	ip->version = 0x6;
301 	ip->payload_len = cpu_to_be16(len);
302 }
303 #endif
304 
efx_gen_tun_header_udp(struct efx_tc_encap_action * encap,u8 len)305 static void efx_gen_tun_header_udp(struct efx_tc_encap_action *encap, u8 len)
306 {
307 	struct ip_tunnel_key *key = &encap->key;
308 	struct udphdr *udp;
309 
310 	udp = (struct udphdr *)(encap->encap_hdr + encap->encap_hdr_len);
311 	encap->encap_hdr_len += sizeof(*udp);
312 
313 	udp->dest = key->tp_dst;
314 	udp_set_len_short(udp, sizeof(*udp) + len);
315 }
316 
efx_gen_tun_header_vxlan(struct efx_tc_encap_action * encap)317 static void efx_gen_tun_header_vxlan(struct efx_tc_encap_action *encap)
318 {
319 	struct ip_tunnel_key *key = &encap->key;
320 	struct vxlanhdr *vxlan;
321 
322 	vxlan = (struct vxlanhdr *)(encap->encap_hdr + encap->encap_hdr_len);
323 	encap->encap_hdr_len += sizeof(*vxlan);
324 
325 	vxlan->vx_flags = VXLAN_HF_VNI;
326 	vxlan->vx_vni = vxlan_vni_field(tunnel_id_to_key32(key->tun_id));
327 }
328 
efx_gen_tun_header_geneve(struct efx_tc_encap_action * encap)329 static void efx_gen_tun_header_geneve(struct efx_tc_encap_action *encap)
330 {
331 	struct ip_tunnel_key *key = &encap->key;
332 	struct genevehdr *geneve;
333 	u32 vni;
334 
335 	geneve = (struct genevehdr *)(encap->encap_hdr + encap->encap_hdr_len);
336 	encap->encap_hdr_len += sizeof(*geneve);
337 
338 	geneve->proto_type = htons(ETH_P_TEB);
339 	/* convert tun_id to host-endian so we can use host arithmetic to
340 	 * extract individual bytes.
341 	 */
342 	vni = ntohl(tunnel_id_to_key32(key->tun_id));
343 	geneve->vni[0] = vni >> 16;
344 	geneve->vni[1] = vni >> 8;
345 	geneve->vni[2] = vni;
346 }
347 
348 #define vxlan_header_l4_len	(sizeof(struct udphdr) + sizeof(struct vxlanhdr))
349 #define vxlan4_header_len	(sizeof(struct ethhdr) + sizeof(struct iphdr) + vxlan_header_l4_len)
efx_gen_vxlan_header_ipv4(struct efx_tc_encap_action * encap)350 static void efx_gen_vxlan_header_ipv4(struct efx_tc_encap_action *encap)
351 {
352 	BUILD_BUG_ON(sizeof(encap->encap_hdr) < vxlan4_header_len);
353 	efx_gen_tun_header_eth(encap, ETH_P_IP);
354 	efx_gen_tun_header_ipv4(encap, IPPROTO_UDP, vxlan_header_l4_len);
355 	efx_gen_tun_header_udp(encap, sizeof(struct vxlanhdr));
356 	efx_gen_tun_header_vxlan(encap);
357 }
358 
359 #define geneve_header_l4_len	(sizeof(struct udphdr) + sizeof(struct genevehdr))
360 #define geneve4_header_len	(sizeof(struct ethhdr) + sizeof(struct iphdr) + geneve_header_l4_len)
efx_gen_geneve_header_ipv4(struct efx_tc_encap_action * encap)361 static void efx_gen_geneve_header_ipv4(struct efx_tc_encap_action *encap)
362 {
363 	BUILD_BUG_ON(sizeof(encap->encap_hdr) < geneve4_header_len);
364 	efx_gen_tun_header_eth(encap, ETH_P_IP);
365 	efx_gen_tun_header_ipv4(encap, IPPROTO_UDP, geneve_header_l4_len);
366 	efx_gen_tun_header_udp(encap, sizeof(struct genevehdr));
367 	efx_gen_tun_header_geneve(encap);
368 }
369 
370 #ifdef CONFIG_IPV6
371 #define vxlan6_header_len	(sizeof(struct ethhdr) + sizeof(struct ipv6hdr) + vxlan_header_l4_len)
efx_gen_vxlan_header_ipv6(struct efx_tc_encap_action * encap)372 static void efx_gen_vxlan_header_ipv6(struct efx_tc_encap_action *encap)
373 {
374 	BUILD_BUG_ON(sizeof(encap->encap_hdr) < vxlan6_header_len);
375 	efx_gen_tun_header_eth(encap, ETH_P_IPV6);
376 	efx_gen_tun_header_ipv6(encap, IPPROTO_UDP, vxlan_header_l4_len);
377 	efx_gen_tun_header_udp(encap, sizeof(struct vxlanhdr));
378 	efx_gen_tun_header_vxlan(encap);
379 }
380 
381 #define geneve6_header_len	(sizeof(struct ethhdr) + sizeof(struct ipv6hdr) + geneve_header_l4_len)
efx_gen_geneve_header_ipv6(struct efx_tc_encap_action * encap)382 static void efx_gen_geneve_header_ipv6(struct efx_tc_encap_action *encap)
383 {
384 	BUILD_BUG_ON(sizeof(encap->encap_hdr) < geneve6_header_len);
385 	efx_gen_tun_header_eth(encap, ETH_P_IPV6);
386 	efx_gen_tun_header_ipv6(encap, IPPROTO_UDP, geneve_header_l4_len);
387 	efx_gen_tun_header_udp(encap, sizeof(struct genevehdr));
388 	efx_gen_tun_header_geneve(encap);
389 }
390 #endif
391 
efx_gen_encap_header(struct efx_nic * efx,struct efx_tc_encap_action * encap)392 static void efx_gen_encap_header(struct efx_nic *efx,
393 				 struct efx_tc_encap_action *encap)
394 {
395 	encap->n_valid = encap->neigh->n_valid;
396 
397 	/* GCC stupidly thinks that only values explicitly listed in the enum
398 	 * definition can _possibly_ be sensible case values, so without this
399 	 * cast it complains about the IPv6 versions.
400 	 */
401 	switch ((int)encap->type) {
402 	case EFX_ENCAP_TYPE_VXLAN:
403 		efx_gen_vxlan_header_ipv4(encap);
404 		break;
405 	case EFX_ENCAP_TYPE_GENEVE:
406 		efx_gen_geneve_header_ipv4(encap);
407 		break;
408 #ifdef CONFIG_IPV6
409 	case EFX_ENCAP_TYPE_VXLAN | EFX_ENCAP_FLAG_IPV6:
410 		efx_gen_vxlan_header_ipv6(encap);
411 		break;
412 	case EFX_ENCAP_TYPE_GENEVE | EFX_ENCAP_FLAG_IPV6:
413 		efx_gen_geneve_header_ipv6(encap);
414 		break;
415 #endif
416 	default:
417 		/* unhandled encap type, can't happen */
418 		if (net_ratelimit())
419 			netif_err(efx, drv, efx->net_dev,
420 				  "Bogus encap type %d, can't generate\n",
421 				  encap->type);
422 
423 		/* Use fallback action. */
424 		encap->n_valid = false;
425 		break;
426 	}
427 }
428 
efx_tc_update_encap(struct efx_nic * efx,struct efx_tc_encap_action * encap)429 static void efx_tc_update_encap(struct efx_nic *efx,
430 				struct efx_tc_encap_action *encap)
431 {
432 	struct efx_tc_action_set_list *acts, *fallback;
433 	struct efx_tc_flow_rule *rule;
434 	struct efx_tc_action_set *act;
435 	int rc;
436 
437 	if (encap->n_valid) {
438 		/* Make sure no rules are using this encap while we change it */
439 		list_for_each_entry(act, &encap->users, encap_user) {
440 			acts = act->user;
441 			if (WARN_ON(!acts)) /* can't happen */
442 				continue;
443 			rule = container_of(acts, struct efx_tc_flow_rule, acts);
444 			if (rule->fallback)
445 				fallback = rule->fallback;
446 			else /* fallback of the fallback: deliver to PF */
447 				fallback = &efx->tc->facts.pf;
448 			rc = efx_mae_update_rule(efx, fallback->fw_id,
449 						 rule->fw_id);
450 			if (rc)
451 				netif_err(efx, drv, efx->net_dev,
452 					  "Failed to update (f) rule %08x rc %d\n",
453 					  rule->fw_id, rc);
454 			else
455 				netif_dbg(efx, drv, efx->net_dev, "Updated (f) rule %08x\n",
456 					  rule->fw_id);
457 		}
458 	}
459 
460 	/* Make sure we don't leak arbitrary bytes on the wire;
461 	 * set an all-0s ethernet header.  A successful call to
462 	 * efx_gen_encap_header() will overwrite this.
463 	 */
464 	memset(encap->encap_hdr, 0, sizeof(encap->encap_hdr));
465 	encap->encap_hdr_len = ETH_HLEN;
466 
467 	if (encap->neigh) {
468 		read_lock_bh(&encap->neigh->lock);
469 		efx_gen_encap_header(efx, encap);
470 		read_unlock_bh(&encap->neigh->lock);
471 	} else {
472 		encap->n_valid = false;
473 	}
474 
475 	rc = efx_mae_update_encap_md(efx, encap);
476 	if (rc) {
477 		netif_err(efx, drv, efx->net_dev,
478 			  "Failed to update encap hdr %08x rc %d\n",
479 			  encap->fw_id, rc);
480 		return;
481 	}
482 	netif_dbg(efx, drv, efx->net_dev, "Updated encap hdr %08x\n",
483 		  encap->fw_id);
484 	if (!encap->n_valid)
485 		return;
486 	/* Update rule users: use the action if they are now ready */
487 	list_for_each_entry(act, &encap->users, encap_user) {
488 		acts = act->user;
489 		if (WARN_ON(!acts)) /* can't happen */
490 			continue;
491 		rule = container_of(acts, struct efx_tc_flow_rule, acts);
492 		if (!efx_tc_check_ready(efx, rule))
493 			continue;
494 		rc = efx_mae_update_rule(efx, acts->fw_id, rule->fw_id);
495 		if (rc)
496 			netif_err(efx, drv, efx->net_dev,
497 				  "Failed to update rule %08x rc %d\n",
498 				  rule->fw_id, rc);
499 		else
500 			netif_dbg(efx, drv, efx->net_dev, "Updated rule %08x\n",
501 				  rule->fw_id);
502 	}
503 }
504 
efx_neigh_update(struct work_struct * work)505 static void efx_neigh_update(struct work_struct *work)
506 {
507 	struct efx_neigh_binder *neigh = container_of(work, struct efx_neigh_binder, work);
508 	struct efx_tc_encap_action *encap;
509 	struct efx_nic *efx = neigh->efx;
510 
511 	mutex_lock(&efx->tc->mutex);
512 	list_for_each_entry(encap, &neigh->users, list)
513 		efx_tc_update_encap(neigh->efx, encap);
514 	/* release ref taken in efx_neigh_event() */
515 	if (refcount_dec_and_test(&neigh->ref))
516 		efx_free_neigh(neigh);
517 	mutex_unlock(&efx->tc->mutex);
518 }
519 
efx_neigh_event(struct efx_nic * efx,struct neighbour * n)520 static int efx_neigh_event(struct efx_nic *efx, struct neighbour *n)
521 {
522 	struct efx_neigh_binder keys = {NULL}, *neigh;
523 	bool n_valid, ipv6 = false;
524 	char ha[ETH_ALEN];
525 	size_t keysize;
526 
527 	if (WARN_ON(!efx->tc))
528 		return NOTIFY_DONE;
529 
530 	if (n->tbl == &arp_tbl) {
531 		keysize = sizeof(keys.dst_ip);
532 #if IS_ENABLED(CONFIG_IPV6)
533 	} else if (n->tbl == &nd_tbl) {
534 		ipv6 = true;
535 		keysize = sizeof(keys.dst_ip6);
536 #endif
537 	} else {
538 		return NOTIFY_DONE;
539 	}
540 	if (!n->parms) {
541 		netif_warn(efx, drv, efx->net_dev, "neigh_event with no parms!\n");
542 		return NOTIFY_DONE;
543 	}
544 	keys.net = read_pnet(&n->parms->net);
545 	if (n->tbl->key_len != keysize) {
546 		netif_warn(efx, drv, efx->net_dev, "neigh_event with bad key_len %u\n",
547 			   n->tbl->key_len);
548 		return NOTIFY_DONE;
549 	}
550 	read_lock_bh(&n->lock); /* Get a consistent view */
551 	memcpy(ha, n->ha, ETH_ALEN);
552 	n_valid = (n->nud_state & NUD_VALID) && !n->dead;
553 	read_unlock_bh(&n->lock);
554 	if (ipv6)
555 		memcpy(&keys.dst_ip6, n->primary_key, n->tbl->key_len);
556 	else
557 		memcpy(&keys.dst_ip, n->primary_key, n->tbl->key_len);
558 	rcu_read_lock();
559 	neigh = rhashtable_lookup_fast(&efx->tc->neigh_ht, &keys,
560 				       efx_neigh_ht_params);
561 	if (!neigh || neigh->dying)
562 		/* We're not interested in this neighbour */
563 		goto done;
564 	write_lock_bh(&neigh->lock);
565 	if (n_valid == neigh->n_valid && !memcmp(ha, neigh->ha, ETH_ALEN)) {
566 		write_unlock_bh(&neigh->lock);
567 		/* Nothing has changed; no work to do */
568 		goto done;
569 	}
570 	neigh->n_valid = n_valid;
571 	memcpy(neigh->ha, ha, ETH_ALEN);
572 	write_unlock_bh(&neigh->lock);
573 	if (refcount_inc_not_zero(&neigh->ref)) {
574 		rcu_read_unlock();
575 		if (!schedule_work(&neigh->work))
576 			/* failed to schedule, release the ref we just took */
577 			if (refcount_dec_and_test(&neigh->ref))
578 				efx_free_neigh(neigh);
579 	} else {
580 done:
581 		rcu_read_unlock();
582 	}
583 	return NOTIFY_DONE;
584 }
585 
efx_tc_check_ready(struct efx_nic * efx,struct efx_tc_flow_rule * rule)586 bool efx_tc_check_ready(struct efx_nic *efx, struct efx_tc_flow_rule *rule)
587 {
588 	struct efx_tc_action_set *act;
589 
590 	/* Encap actions can only be offloaded if they have valid
591 	 * neighbour info for the outer Ethernet header.
592 	 */
593 	list_for_each_entry(act, &rule->acts.list, list)
594 		if (act->encap_md && !act->encap_md->n_valid)
595 			return false;
596 	return true;
597 }
598 
efx_tc_flower_create_encap_md(struct efx_nic * efx,const struct ip_tunnel_info * info,struct net_device * egdev,struct netlink_ext_ack * extack)599 struct efx_tc_encap_action *efx_tc_flower_create_encap_md(
600 			struct efx_nic *efx, const struct ip_tunnel_info *info,
601 			struct net_device *egdev, struct netlink_ext_ack *extack)
602 {
603 	enum efx_encap_type type = efx_tc_indr_netdev_type(egdev);
604 	struct efx_tc_encap_action *encap, *old;
605 	struct efx_rep *to_efv;
606 	s64 rc;
607 
608 	if (type == EFX_ENCAP_TYPE_NONE) {
609 		/* dest is not an encap device */
610 		NL_SET_ERR_MSG_MOD(extack, "Not a (supported) tunnel device but tunnel_key is set");
611 		return ERR_PTR(-EOPNOTSUPP);
612 	}
613 	rc = efx_mae_check_encap_type_supported(efx, type);
614 	if (rc < 0) {
615 		NL_SET_ERR_MSG_MOD(extack, "Firmware reports no support for this tunnel type");
616 		return ERR_PTR(rc);
617 	}
618 	/* No support yet for Geneve options */
619 	if (info->options_len) {
620 		NL_SET_ERR_MSG_MOD(extack, "Unsupported tunnel options");
621 		return ERR_PTR(-EOPNOTSUPP);
622 	}
623 	switch (info->mode) {
624 	case IP_TUNNEL_INFO_TX:
625 		break;
626 	case IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_IPV6:
627 		type |= EFX_ENCAP_FLAG_IPV6;
628 		break;
629 	default:
630 		NL_SET_ERR_MSG_FMT_MOD(extack, "Unsupported tunnel mode %u",
631 				       info->mode);
632 		return ERR_PTR(-EOPNOTSUPP);
633 	}
634 	encap = kzalloc_obj(*encap, GFP_KERNEL_ACCOUNT);
635 	if (!encap)
636 		return ERR_PTR(-ENOMEM);
637 	encap->type = type;
638 	encap->key = info->key;
639 	INIT_LIST_HEAD(&encap->users);
640 	old = rhashtable_lookup_get_insert_fast(&efx->tc->encap_ht,
641 						&encap->linkage,
642 						efx_tc_encap_ht_params);
643 	if (old) {
644 		/* don't need our new entry */
645 		kfree(encap);
646 		if (IS_ERR(old)) /* oh dear, it's actually an error */
647 			return ERR_CAST(old);
648 		if (!refcount_inc_not_zero(&old->ref))
649 			return ERR_PTR(-EAGAIN);
650 		/* existing entry found, ref taken */
651 		return old;
652 	}
653 
654 	rc = efx_bind_neigh(efx, encap, dev_net(egdev), extack);
655 	if (rc < 0)
656 		goto out_remove;
657 	to_efv = efx_tc_flower_lookup_efv(efx, encap->neigh->egdev);
658 	if (IS_ERR(to_efv)) {
659 		/* neigh->egdev isn't ours */
660 		NL_SET_ERR_MSG_MOD(extack, "Tunnel egress device not on switch");
661 		rc = PTR_ERR(to_efv);
662 		goto out_release;
663 	}
664 	rc = efx_tc_flower_external_mport(efx, to_efv);
665 	if (rc < 0) {
666 		NL_SET_ERR_MSG_MOD(extack, "Failed to identify tunnel egress m-port");
667 		goto out_release;
668 	}
669 	encap->dest_mport = rc;
670 	read_lock_bh(&encap->neigh->lock);
671 	efx_gen_encap_header(efx, encap);
672 	read_unlock_bh(&encap->neigh->lock);
673 
674 	rc = efx_mae_allocate_encap_md(efx, encap);
675 	if (rc < 0) {
676 		NL_SET_ERR_MSG_MOD(extack, "Failed to write tunnel header to hw");
677 		goto out_release;
678 	}
679 
680 	/* ref and return */
681 	refcount_set(&encap->ref, 1);
682 	return encap;
683 out_release:
684 	efx_release_neigh(efx, encap);
685 out_remove:
686 	rhashtable_remove_fast(&efx->tc->encap_ht, &encap->linkage,
687 			       efx_tc_encap_ht_params);
688 	kfree(encap);
689 	return ERR_PTR(rc);
690 }
691 
efx_tc_flower_release_encap_md(struct efx_nic * efx,struct efx_tc_encap_action * encap)692 void efx_tc_flower_release_encap_md(struct efx_nic *efx,
693 				    struct efx_tc_encap_action *encap)
694 {
695 	if (!refcount_dec_and_test(&encap->ref))
696 		return; /* still in use */
697 	efx_release_neigh(efx, encap);
698 	rhashtable_remove_fast(&efx->tc->encap_ht, &encap->linkage,
699 			       efx_tc_encap_ht_params);
700 	efx_mae_free_encap_md(efx, encap);
701 	kfree(encap);
702 }
703 
efx_tc_remove_neigh_users(struct efx_nic * efx,struct efx_neigh_binder * neigh)704 static void efx_tc_remove_neigh_users(struct efx_nic *efx, struct efx_neigh_binder *neigh)
705 {
706 	struct efx_tc_encap_action *encap, *next;
707 
708 	list_for_each_entry_safe(encap, next, &neigh->users, list) {
709 		/* Should cause neigh usage count to fall to zero, freeing it */
710 		efx_release_neigh(efx, encap);
711 		/* The encap has lost its neigh, so it's now unready */
712 		efx_tc_update_encap(efx, encap);
713 	}
714 }
715 
efx_tc_unregister_egdev(struct efx_nic * efx,struct net_device * net_dev)716 void efx_tc_unregister_egdev(struct efx_nic *efx, struct net_device *net_dev)
717 {
718 	struct efx_neigh_binder *neigh;
719 	struct rhashtable_iter walk;
720 
721 	mutex_lock(&efx->tc->mutex);
722 	rhashtable_walk_enter(&efx->tc->neigh_ht, &walk);
723 	rhashtable_walk_start(&walk);
724 	while ((neigh = rhashtable_walk_next(&walk)) != NULL) {
725 		if (IS_ERR(neigh))
726 			continue;
727 		if (neigh->egdev != net_dev)
728 			continue;
729 		neigh->dying = true;
730 		rhashtable_walk_stop(&walk);
731 		synchronize_rcu(); /* Make sure any updates see dying flag */
732 		efx_tc_remove_neigh_users(efx, neigh); /* might sleep */
733 		rhashtable_walk_start(&walk);
734 	}
735 	rhashtable_walk_stop(&walk);
736 	rhashtable_walk_exit(&walk);
737 	mutex_unlock(&efx->tc->mutex);
738 }
739 
efx_tc_netevent_event(struct efx_nic * efx,unsigned long event,void * ptr)740 int efx_tc_netevent_event(struct efx_nic *efx, unsigned long event,
741 			  void *ptr)
742 {
743 	if (efx->type->is_vf)
744 		return NOTIFY_DONE;
745 
746 	switch (event) {
747 	case NETEVENT_NEIGH_UPDATE:
748 		return efx_neigh_event(efx, ptr);
749 	default:
750 		return NOTIFY_DONE;
751 	}
752 }
753