xref: /openbmc/linux/drivers/net/netdevsim/fib.c (revision 974be75f)
1 /*
2  * Copyright (c) 2018 Cumulus Networks. All rights reserved.
3  * Copyright (c) 2018 David Ahern <dsa@cumulusnetworks.com>
4  *
5  * This software is licensed under the GNU General License Version 2,
6  * June 1991 as shown in the file COPYING in the top-level directory of this
7  * source tree.
8  *
9  * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
10  * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
11  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
12  * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
13  * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
14  * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
15  */
16 
17 #include <linux/bitmap.h>
18 #include <linux/in6.h>
19 #include <linux/kernel.h>
20 #include <linux/list.h>
21 #include <linux/rhashtable.h>
22 #include <linux/spinlock_types.h>
23 #include <linux/types.h>
24 #include <net/fib_notifier.h>
25 #include <net/inet_dscp.h>
26 #include <net/ip_fib.h>
27 #include <net/ip6_fib.h>
28 #include <net/fib_rules.h>
29 #include <net/net_namespace.h>
30 #include <net/nexthop.h>
31 #include <linux/debugfs.h>
32 
33 #include "netdevsim.h"
34 
35 struct nsim_fib_entry {
36 	u64 max;
37 	atomic64_t num;
38 };
39 
40 struct nsim_per_fib_data {
41 	struct nsim_fib_entry fib;
42 	struct nsim_fib_entry rules;
43 };
44 
45 struct nsim_fib_data {
46 	struct notifier_block fib_nb;
47 	struct nsim_per_fib_data ipv4;
48 	struct nsim_per_fib_data ipv6;
49 	struct nsim_fib_entry nexthops;
50 	struct rhashtable fib_rt_ht;
51 	struct list_head fib_rt_list;
52 	struct mutex fib_lock; /* Protects FIB HT and list */
53 	struct notifier_block nexthop_nb;
54 	struct rhashtable nexthop_ht;
55 	struct devlink *devlink;
56 	struct work_struct fib_event_work;
57 	struct work_struct fib_flush_work;
58 	struct list_head fib_event_queue;
59 	spinlock_t fib_event_queue_lock; /* Protects fib event queue list */
60 	struct mutex nh_lock; /* Protects NH HT */
61 	struct dentry *ddir;
62 	bool fail_route_offload;
63 	bool fail_res_nexthop_group_replace;
64 	bool fail_nexthop_bucket_replace;
65 	bool fail_route_delete;
66 };
67 
68 struct nsim_fib_rt_key {
69 	unsigned char addr[sizeof(struct in6_addr)];
70 	unsigned char prefix_len;
71 	int family;
72 	u32 tb_id;
73 };
74 
75 struct nsim_fib_rt {
76 	struct nsim_fib_rt_key key;
77 	struct rhash_head ht_node;
78 	struct list_head list;	/* Member of fib_rt_list */
79 };
80 
81 struct nsim_fib4_rt {
82 	struct nsim_fib_rt common;
83 	struct fib_info *fi;
84 	dscp_t dscp;
85 	u8 type;
86 };
87 
88 struct nsim_fib6_rt {
89 	struct nsim_fib_rt common;
90 	struct list_head nh_list;
91 	unsigned int nhs;
92 };
93 
94 struct nsim_fib6_rt_nh {
95 	struct list_head list;	/* Member of nh_list */
96 	struct fib6_info *rt;
97 };
98 
99 struct nsim_fib6_event {
100 	struct fib6_info **rt_arr;
101 	unsigned int nrt6;
102 };
103 
104 struct nsim_fib_event {
105 	struct list_head list; /* node in fib queue */
106 	union {
107 		struct fib_entry_notifier_info fen_info;
108 		struct nsim_fib6_event fib6_event;
109 	};
110 	struct nsim_fib_data *data;
111 	unsigned long event;
112 	int family;
113 };
114 
115 static const struct rhashtable_params nsim_fib_rt_ht_params = {
116 	.key_offset = offsetof(struct nsim_fib_rt, key),
117 	.head_offset = offsetof(struct nsim_fib_rt, ht_node),
118 	.key_len = sizeof(struct nsim_fib_rt_key),
119 	.automatic_shrinking = true,
120 };
121 
122 struct nsim_nexthop {
123 	struct rhash_head ht_node;
124 	u64 occ;
125 	u32 id;
126 	bool is_resilient;
127 };
128 
129 static const struct rhashtable_params nsim_nexthop_ht_params = {
130 	.key_offset = offsetof(struct nsim_nexthop, id),
131 	.head_offset = offsetof(struct nsim_nexthop, ht_node),
132 	.key_len = sizeof(u32),
133 	.automatic_shrinking = true,
134 };
135 
nsim_fib_get_val(struct nsim_fib_data * fib_data,enum nsim_resource_id res_id,bool max)136 u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
137 		     enum nsim_resource_id res_id, bool max)
138 {
139 	struct nsim_fib_entry *entry;
140 
141 	switch (res_id) {
142 	case NSIM_RESOURCE_IPV4_FIB:
143 		entry = &fib_data->ipv4.fib;
144 		break;
145 	case NSIM_RESOURCE_IPV4_FIB_RULES:
146 		entry = &fib_data->ipv4.rules;
147 		break;
148 	case NSIM_RESOURCE_IPV6_FIB:
149 		entry = &fib_data->ipv6.fib;
150 		break;
151 	case NSIM_RESOURCE_IPV6_FIB_RULES:
152 		entry = &fib_data->ipv6.rules;
153 		break;
154 	case NSIM_RESOURCE_NEXTHOPS:
155 		entry = &fib_data->nexthops;
156 		break;
157 	default:
158 		return 0;
159 	}
160 
161 	return max ? entry->max : atomic64_read(&entry->num);
162 }
163 
nsim_fib_set_max(struct nsim_fib_data * fib_data,enum nsim_resource_id res_id,u64 val)164 static void nsim_fib_set_max(struct nsim_fib_data *fib_data,
165 			     enum nsim_resource_id res_id, u64 val)
166 {
167 	struct nsim_fib_entry *entry;
168 
169 	switch (res_id) {
170 	case NSIM_RESOURCE_IPV4_FIB:
171 		entry = &fib_data->ipv4.fib;
172 		break;
173 	case NSIM_RESOURCE_IPV4_FIB_RULES:
174 		entry = &fib_data->ipv4.rules;
175 		break;
176 	case NSIM_RESOURCE_IPV6_FIB:
177 		entry = &fib_data->ipv6.fib;
178 		break;
179 	case NSIM_RESOURCE_IPV6_FIB_RULES:
180 		entry = &fib_data->ipv6.rules;
181 		break;
182 	case NSIM_RESOURCE_NEXTHOPS:
183 		entry = &fib_data->nexthops;
184 		break;
185 	default:
186 		WARN_ON(1);
187 		return;
188 	}
189 	entry->max = val;
190 }
191 
nsim_fib_rule_account(struct nsim_fib_entry * entry,bool add,struct netlink_ext_ack * extack)192 static int nsim_fib_rule_account(struct nsim_fib_entry *entry, bool add,
193 				 struct netlink_ext_ack *extack)
194 {
195 	int err = 0;
196 
197 	if (add) {
198 		if (!atomic64_add_unless(&entry->num, 1, entry->max)) {
199 			err = -ENOSPC;
200 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib rule entries");
201 		}
202 	} else {
203 		atomic64_dec_if_positive(&entry->num);
204 	}
205 
206 	return err;
207 }
208 
nsim_fib_rule_event(struct nsim_fib_data * data,struct fib_notifier_info * info,bool add)209 static int nsim_fib_rule_event(struct nsim_fib_data *data,
210 			       struct fib_notifier_info *info, bool add)
211 {
212 	struct netlink_ext_ack *extack = info->extack;
213 	int err = 0;
214 
215 	switch (info->family) {
216 	case AF_INET:
217 		err = nsim_fib_rule_account(&data->ipv4.rules, add, extack);
218 		break;
219 	case AF_INET6:
220 		err = nsim_fib_rule_account(&data->ipv6.rules, add, extack);
221 		break;
222 	}
223 
224 	return err;
225 }
226 
nsim_fib_account(struct nsim_fib_entry * entry,bool add)227 static int nsim_fib_account(struct nsim_fib_entry *entry, bool add)
228 {
229 	int err = 0;
230 
231 	if (add) {
232 		if (!atomic64_add_unless(&entry->num, 1, entry->max))
233 			err = -ENOSPC;
234 	} else {
235 		atomic64_dec_if_positive(&entry->num);
236 	}
237 
238 	return err;
239 }
240 
nsim_fib_rt_init(struct nsim_fib_data * data,struct nsim_fib_rt * fib_rt,const void * addr,size_t addr_len,unsigned int prefix_len,int family,u32 tb_id)241 static void nsim_fib_rt_init(struct nsim_fib_data *data,
242 			     struct nsim_fib_rt *fib_rt, const void *addr,
243 			     size_t addr_len, unsigned int prefix_len,
244 			     int family, u32 tb_id)
245 {
246 	memcpy(fib_rt->key.addr, addr, addr_len);
247 	fib_rt->key.prefix_len = prefix_len;
248 	fib_rt->key.family = family;
249 	fib_rt->key.tb_id = tb_id;
250 	list_add(&fib_rt->list, &data->fib_rt_list);
251 }
252 
nsim_fib_rt_fini(struct nsim_fib_rt * fib_rt)253 static void nsim_fib_rt_fini(struct nsim_fib_rt *fib_rt)
254 {
255 	list_del(&fib_rt->list);
256 }
257 
nsim_fib_rt_lookup(struct rhashtable * fib_rt_ht,const void * addr,size_t addr_len,unsigned int prefix_len,int family,u32 tb_id)258 static struct nsim_fib_rt *nsim_fib_rt_lookup(struct rhashtable *fib_rt_ht,
259 					      const void *addr, size_t addr_len,
260 					      unsigned int prefix_len,
261 					      int family, u32 tb_id)
262 {
263 	struct nsim_fib_rt_key key;
264 
265 	memset(&key, 0, sizeof(key));
266 	memcpy(key.addr, addr, addr_len);
267 	key.prefix_len = prefix_len;
268 	key.family = family;
269 	key.tb_id = tb_id;
270 
271 	return rhashtable_lookup_fast(fib_rt_ht, &key, nsim_fib_rt_ht_params);
272 }
273 
274 static struct nsim_fib4_rt *
nsim_fib4_rt_create(struct nsim_fib_data * data,struct fib_entry_notifier_info * fen_info)275 nsim_fib4_rt_create(struct nsim_fib_data *data,
276 		    struct fib_entry_notifier_info *fen_info)
277 {
278 	struct nsim_fib4_rt *fib4_rt;
279 
280 	fib4_rt = kzalloc(sizeof(*fib4_rt), GFP_KERNEL);
281 	if (!fib4_rt)
282 		return NULL;
283 
284 	nsim_fib_rt_init(data, &fib4_rt->common, &fen_info->dst, sizeof(u32),
285 			 fen_info->dst_len, AF_INET, fen_info->tb_id);
286 
287 	fib4_rt->fi = fen_info->fi;
288 	fib_info_hold(fib4_rt->fi);
289 	fib4_rt->dscp = fen_info->dscp;
290 	fib4_rt->type = fen_info->type;
291 
292 	return fib4_rt;
293 }
294 
nsim_fib4_rt_destroy(struct nsim_fib4_rt * fib4_rt)295 static void nsim_fib4_rt_destroy(struct nsim_fib4_rt *fib4_rt)
296 {
297 	fib_info_put(fib4_rt->fi);
298 	nsim_fib_rt_fini(&fib4_rt->common);
299 	kfree(fib4_rt);
300 }
301 
302 static struct nsim_fib4_rt *
nsim_fib4_rt_lookup(struct rhashtable * fib_rt_ht,const struct fib_entry_notifier_info * fen_info)303 nsim_fib4_rt_lookup(struct rhashtable *fib_rt_ht,
304 		    const struct fib_entry_notifier_info *fen_info)
305 {
306 	struct nsim_fib_rt *fib_rt;
307 
308 	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &fen_info->dst, sizeof(u32),
309 				    fen_info->dst_len, AF_INET,
310 				    fen_info->tb_id);
311 	if (!fib_rt)
312 		return NULL;
313 
314 	return container_of(fib_rt, struct nsim_fib4_rt, common);
315 }
316 
317 static void
nsim_fib4_rt_offload_failed_flag_set(struct net * net,struct fib_entry_notifier_info * fen_info)318 nsim_fib4_rt_offload_failed_flag_set(struct net *net,
319 				     struct fib_entry_notifier_info *fen_info)
320 {
321 	u32 *p_dst = (u32 *)&fen_info->dst;
322 	struct fib_rt_info fri;
323 
324 	fri.fi = fen_info->fi;
325 	fri.tb_id = fen_info->tb_id;
326 	fri.dst = cpu_to_be32(*p_dst);
327 	fri.dst_len = fen_info->dst_len;
328 	fri.dscp = fen_info->dscp;
329 	fri.type = fen_info->type;
330 	fri.offload = false;
331 	fri.trap = false;
332 	fri.offload_failed = true;
333 	fib_alias_hw_flags_set(net, &fri);
334 }
335 
nsim_fib4_rt_hw_flags_set(struct net * net,const struct nsim_fib4_rt * fib4_rt,bool trap)336 static void nsim_fib4_rt_hw_flags_set(struct net *net,
337 				      const struct nsim_fib4_rt *fib4_rt,
338 				      bool trap)
339 {
340 	u32 *p_dst = (u32 *) fib4_rt->common.key.addr;
341 	int dst_len = fib4_rt->common.key.prefix_len;
342 	struct fib_rt_info fri;
343 
344 	fri.fi = fib4_rt->fi;
345 	fri.tb_id = fib4_rt->common.key.tb_id;
346 	fri.dst = cpu_to_be32(*p_dst);
347 	fri.dst_len = dst_len;
348 	fri.dscp = fib4_rt->dscp;
349 	fri.type = fib4_rt->type;
350 	fri.offload = false;
351 	fri.trap = trap;
352 	fri.offload_failed = false;
353 	fib_alias_hw_flags_set(net, &fri);
354 }
355 
nsim_fib4_rt_add(struct nsim_fib_data * data,struct nsim_fib4_rt * fib4_rt)356 static int nsim_fib4_rt_add(struct nsim_fib_data *data,
357 			    struct nsim_fib4_rt *fib4_rt)
358 {
359 	struct net *net = devlink_net(data->devlink);
360 	int err;
361 
362 	err = rhashtable_insert_fast(&data->fib_rt_ht,
363 				     &fib4_rt->common.ht_node,
364 				     nsim_fib_rt_ht_params);
365 	if (err)
366 		goto err_fib_dismiss;
367 
368 	/* Simulate hardware programming latency. */
369 	msleep(1);
370 	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
371 
372 	return 0;
373 
374 err_fib_dismiss:
375 	/* Drop the accounting that was increased from the notification
376 	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
377 	 */
378 	nsim_fib_account(&data->ipv4.fib, false);
379 	return err;
380 }
381 
nsim_fib4_rt_replace(struct nsim_fib_data * data,struct nsim_fib4_rt * fib4_rt,struct nsim_fib4_rt * fib4_rt_old)382 static int nsim_fib4_rt_replace(struct nsim_fib_data *data,
383 				struct nsim_fib4_rt *fib4_rt,
384 				struct nsim_fib4_rt *fib4_rt_old)
385 {
386 	struct net *net = devlink_net(data->devlink);
387 	int err;
388 
389 	/* We are replacing a route, so need to remove the accounting which
390 	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
391 	 */
392 	err = nsim_fib_account(&data->ipv4.fib, false);
393 	if (err)
394 		return err;
395 	err = rhashtable_replace_fast(&data->fib_rt_ht,
396 				      &fib4_rt_old->common.ht_node,
397 				      &fib4_rt->common.ht_node,
398 				      nsim_fib_rt_ht_params);
399 	if (err)
400 		return err;
401 
402 	msleep(1);
403 	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
404 
405 	nsim_fib4_rt_hw_flags_set(net, fib4_rt_old, false);
406 	nsim_fib4_rt_destroy(fib4_rt_old);
407 
408 	return 0;
409 }
410 
nsim_fib4_rt_insert(struct nsim_fib_data * data,struct fib_entry_notifier_info * fen_info)411 static int nsim_fib4_rt_insert(struct nsim_fib_data *data,
412 			       struct fib_entry_notifier_info *fen_info)
413 {
414 	struct nsim_fib4_rt *fib4_rt, *fib4_rt_old;
415 	int err;
416 
417 	if (data->fail_route_offload) {
418 		/* For testing purposes, user set debugfs fail_route_offload
419 		 * value to true. Simulate hardware programming latency and then
420 		 * fail.
421 		 */
422 		msleep(1);
423 		return -EINVAL;
424 	}
425 
426 	fib4_rt = nsim_fib4_rt_create(data, fen_info);
427 	if (!fib4_rt)
428 		return -ENOMEM;
429 
430 	fib4_rt_old = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
431 	if (!fib4_rt_old)
432 		err = nsim_fib4_rt_add(data, fib4_rt);
433 	else
434 		err = nsim_fib4_rt_replace(data, fib4_rt, fib4_rt_old);
435 
436 	if (err)
437 		nsim_fib4_rt_destroy(fib4_rt);
438 
439 	return err;
440 }
441 
nsim_fib4_rt_remove(struct nsim_fib_data * data,const struct fib_entry_notifier_info * fen_info)442 static void nsim_fib4_rt_remove(struct nsim_fib_data *data,
443 				const struct fib_entry_notifier_info *fen_info)
444 {
445 	struct nsim_fib4_rt *fib4_rt;
446 
447 	fib4_rt = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
448 	if (!fib4_rt)
449 		return;
450 
451 	rhashtable_remove_fast(&data->fib_rt_ht, &fib4_rt->common.ht_node,
452 			       nsim_fib_rt_ht_params);
453 	nsim_fib4_rt_destroy(fib4_rt);
454 }
455 
nsim_fib4_event(struct nsim_fib_data * data,struct fib_entry_notifier_info * fen_info,unsigned long event)456 static int nsim_fib4_event(struct nsim_fib_data *data,
457 			   struct fib_entry_notifier_info *fen_info,
458 			   unsigned long event)
459 {
460 	int err = 0;
461 
462 	switch (event) {
463 	case FIB_EVENT_ENTRY_REPLACE:
464 		err = nsim_fib4_rt_insert(data, fen_info);
465 		if (err) {
466 			struct net *net = devlink_net(data->devlink);
467 
468 			nsim_fib4_rt_offload_failed_flag_set(net, fen_info);
469 		}
470 		break;
471 	case FIB_EVENT_ENTRY_DEL:
472 		nsim_fib4_rt_remove(data, fen_info);
473 		break;
474 	default:
475 		break;
476 	}
477 
478 	return err;
479 }
480 
481 static struct nsim_fib6_rt_nh *
nsim_fib6_rt_nh_find(const struct nsim_fib6_rt * fib6_rt,const struct fib6_info * rt)482 nsim_fib6_rt_nh_find(const struct nsim_fib6_rt *fib6_rt,
483 		     const struct fib6_info *rt)
484 {
485 	struct nsim_fib6_rt_nh *fib6_rt_nh;
486 
487 	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list) {
488 		if (fib6_rt_nh->rt == rt)
489 			return fib6_rt_nh;
490 	}
491 
492 	return NULL;
493 }
494 
nsim_fib6_rt_nh_add(struct nsim_fib6_rt * fib6_rt,struct fib6_info * rt)495 static int nsim_fib6_rt_nh_add(struct nsim_fib6_rt *fib6_rt,
496 			       struct fib6_info *rt)
497 {
498 	struct nsim_fib6_rt_nh *fib6_rt_nh;
499 
500 	fib6_rt_nh = kzalloc(sizeof(*fib6_rt_nh), GFP_KERNEL);
501 	if (!fib6_rt_nh)
502 		return -ENOMEM;
503 
504 	fib6_info_hold(rt);
505 	fib6_rt_nh->rt = rt;
506 	list_add_tail(&fib6_rt_nh->list, &fib6_rt->nh_list);
507 	fib6_rt->nhs++;
508 
509 	return 0;
510 }
511 
512 #if IS_ENABLED(CONFIG_IPV6)
nsim_rt6_release(struct fib6_info * rt)513 static void nsim_rt6_release(struct fib6_info *rt)
514 {
515 	fib6_info_release(rt);
516 }
517 #else
nsim_rt6_release(struct fib6_info * rt)518 static void nsim_rt6_release(struct fib6_info *rt)
519 {
520 }
521 #endif
522 
nsim_fib6_rt_nh_del(struct nsim_fib6_rt * fib6_rt,const struct fib6_info * rt)523 static void nsim_fib6_rt_nh_del(struct nsim_fib6_rt *fib6_rt,
524 				const struct fib6_info *rt)
525 {
526 	struct nsim_fib6_rt_nh *fib6_rt_nh;
527 
528 	fib6_rt_nh = nsim_fib6_rt_nh_find(fib6_rt, rt);
529 	if (!fib6_rt_nh)
530 		return;
531 
532 	fib6_rt->nhs--;
533 	list_del(&fib6_rt_nh->list);
534 	nsim_rt6_release(fib6_rt_nh->rt);
535 	kfree(fib6_rt_nh);
536 }
537 
538 static struct nsim_fib6_rt *
nsim_fib6_rt_create(struct nsim_fib_data * data,struct fib6_info ** rt_arr,unsigned int nrt6)539 nsim_fib6_rt_create(struct nsim_fib_data *data,
540 		    struct fib6_info **rt_arr, unsigned int nrt6)
541 {
542 	struct fib6_info *rt = rt_arr[0];
543 	struct nsim_fib6_rt *fib6_rt;
544 	int i = 0;
545 	int err;
546 
547 	fib6_rt = kzalloc(sizeof(*fib6_rt), GFP_KERNEL);
548 	if (!fib6_rt)
549 		return ERR_PTR(-ENOMEM);
550 
551 	nsim_fib_rt_init(data, &fib6_rt->common, &rt->fib6_dst.addr,
552 			 sizeof(rt->fib6_dst.addr), rt->fib6_dst.plen, AF_INET6,
553 			 rt->fib6_table->tb6_id);
554 
555 	/* We consider a multipath IPv6 route as one entry, but it can be made
556 	 * up from several fib6_info structs (one for each nexthop), so we
557 	 * add them all to the same list under the entry.
558 	 */
559 	INIT_LIST_HEAD(&fib6_rt->nh_list);
560 
561 	for (i = 0; i < nrt6; i++) {
562 		err = nsim_fib6_rt_nh_add(fib6_rt, rt_arr[i]);
563 		if (err)
564 			goto err_fib6_rt_nh_del;
565 	}
566 
567 	return fib6_rt;
568 
569 err_fib6_rt_nh_del:
570 	for (i--; i >= 0; i--) {
571 		nsim_fib6_rt_nh_del(fib6_rt, rt_arr[i]);
572 	}
573 	nsim_fib_rt_fini(&fib6_rt->common);
574 	kfree(fib6_rt);
575 	return ERR_PTR(err);
576 }
577 
nsim_fib6_rt_destroy(struct nsim_fib6_rt * fib6_rt)578 static void nsim_fib6_rt_destroy(struct nsim_fib6_rt *fib6_rt)
579 {
580 	struct nsim_fib6_rt_nh *iter, *tmp;
581 
582 	list_for_each_entry_safe(iter, tmp, &fib6_rt->nh_list, list)
583 		nsim_fib6_rt_nh_del(fib6_rt, iter->rt);
584 	WARN_ON_ONCE(!list_empty(&fib6_rt->nh_list));
585 	nsim_fib_rt_fini(&fib6_rt->common);
586 	kfree(fib6_rt);
587 }
588 
589 static struct nsim_fib6_rt *
nsim_fib6_rt_lookup(struct rhashtable * fib_rt_ht,const struct fib6_info * rt)590 nsim_fib6_rt_lookup(struct rhashtable *fib_rt_ht, const struct fib6_info *rt)
591 {
592 	struct nsim_fib_rt *fib_rt;
593 
594 	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &rt->fib6_dst.addr,
595 				    sizeof(rt->fib6_dst.addr),
596 				    rt->fib6_dst.plen, AF_INET6,
597 				    rt->fib6_table->tb6_id);
598 	if (!fib_rt)
599 		return NULL;
600 
601 	return container_of(fib_rt, struct nsim_fib6_rt, common);
602 }
603 
nsim_fib6_rt_append(struct nsim_fib_data * data,struct nsim_fib6_event * fib6_event)604 static int nsim_fib6_rt_append(struct nsim_fib_data *data,
605 			       struct nsim_fib6_event *fib6_event)
606 {
607 	struct fib6_info *rt = fib6_event->rt_arr[0];
608 	struct nsim_fib6_rt *fib6_rt;
609 	int i, err;
610 
611 	if (data->fail_route_offload) {
612 		/* For testing purposes, user set debugfs fail_route_offload
613 		 * value to true. Simulate hardware programming latency and then
614 		 * fail.
615 		 */
616 		msleep(1);
617 		return -EINVAL;
618 	}
619 
620 	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
621 	if (!fib6_rt)
622 		return -EINVAL;
623 
624 	for (i = 0; i < fib6_event->nrt6; i++) {
625 		err = nsim_fib6_rt_nh_add(fib6_rt, fib6_event->rt_arr[i]);
626 		if (err)
627 			goto err_fib6_rt_nh_del;
628 
629 		WRITE_ONCE(fib6_event->rt_arr[i]->trap, true);
630 	}
631 
632 	return 0;
633 
634 err_fib6_rt_nh_del:
635 	for (i--; i >= 0; i--) {
636 		WRITE_ONCE(fib6_event->rt_arr[i]->trap, false);
637 		nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
638 	}
639 	return err;
640 }
641 
642 #if IS_ENABLED(CONFIG_IPV6)
nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data * data,struct fib6_info ** rt_arr,unsigned int nrt6)643 static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
644 						 struct fib6_info **rt_arr,
645 						 unsigned int nrt6)
646 
647 {
648 	struct net *net = devlink_net(data->devlink);
649 	int i;
650 
651 	for (i = 0; i < nrt6; i++)
652 		fib6_info_hw_flags_set(net, rt_arr[i], false, false, true);
653 }
654 #else
nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data * data,struct fib6_info ** rt_arr,unsigned int nrt6)655 static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
656 						 struct fib6_info **rt_arr,
657 						 unsigned int nrt6)
658 {
659 }
660 #endif
661 
662 #if IS_ENABLED(CONFIG_IPV6)
nsim_fib6_rt_hw_flags_set(struct nsim_fib_data * data,const struct nsim_fib6_rt * fib6_rt,bool trap)663 static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
664 				      const struct nsim_fib6_rt *fib6_rt,
665 				      bool trap)
666 {
667 	struct net *net = devlink_net(data->devlink);
668 	struct nsim_fib6_rt_nh *fib6_rt_nh;
669 
670 	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list)
671 		fib6_info_hw_flags_set(net, fib6_rt_nh->rt, false, trap, false);
672 }
673 #else
nsim_fib6_rt_hw_flags_set(struct nsim_fib_data * data,const struct nsim_fib6_rt * fib6_rt,bool trap)674 static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
675 				      const struct nsim_fib6_rt *fib6_rt,
676 				      bool trap)
677 {
678 }
679 #endif
680 
nsim_fib6_rt_add(struct nsim_fib_data * data,struct nsim_fib6_rt * fib6_rt)681 static int nsim_fib6_rt_add(struct nsim_fib_data *data,
682 			    struct nsim_fib6_rt *fib6_rt)
683 {
684 	int err;
685 
686 	err = rhashtable_insert_fast(&data->fib_rt_ht,
687 				     &fib6_rt->common.ht_node,
688 				     nsim_fib_rt_ht_params);
689 
690 	if (err)
691 		goto err_fib_dismiss;
692 
693 	msleep(1);
694 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
695 
696 	return 0;
697 
698 err_fib_dismiss:
699 	/* Drop the accounting that was increased from the notification
700 	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
701 	 */
702 	nsim_fib_account(&data->ipv6.fib, false);
703 	return err;
704 }
705 
nsim_fib6_rt_replace(struct nsim_fib_data * data,struct nsim_fib6_rt * fib6_rt,struct nsim_fib6_rt * fib6_rt_old)706 static int nsim_fib6_rt_replace(struct nsim_fib_data *data,
707 				struct nsim_fib6_rt *fib6_rt,
708 				struct nsim_fib6_rt *fib6_rt_old)
709 {
710 	int err;
711 
712 	/* We are replacing a route, so need to remove the accounting which
713 	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
714 	 */
715 	err = nsim_fib_account(&data->ipv6.fib, false);
716 	if (err)
717 		return err;
718 
719 	err = rhashtable_replace_fast(&data->fib_rt_ht,
720 				      &fib6_rt_old->common.ht_node,
721 				      &fib6_rt->common.ht_node,
722 				      nsim_fib_rt_ht_params);
723 
724 	if (err)
725 		return err;
726 
727 	msleep(1);
728 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
729 
730 	nsim_fib6_rt_hw_flags_set(data, fib6_rt_old, false);
731 	nsim_fib6_rt_destroy(fib6_rt_old);
732 
733 	return 0;
734 }
735 
nsim_fib6_rt_insert(struct nsim_fib_data * data,struct nsim_fib6_event * fib6_event)736 static int nsim_fib6_rt_insert(struct nsim_fib_data *data,
737 			       struct nsim_fib6_event *fib6_event)
738 {
739 	struct fib6_info *rt = fib6_event->rt_arr[0];
740 	struct nsim_fib6_rt *fib6_rt, *fib6_rt_old;
741 	int err;
742 
743 	if (data->fail_route_offload) {
744 		/* For testing purposes, user set debugfs fail_route_offload
745 		 * value to true. Simulate hardware programming latency and then
746 		 * fail.
747 		 */
748 		msleep(1);
749 		return -EINVAL;
750 	}
751 
752 	fib6_rt = nsim_fib6_rt_create(data, fib6_event->rt_arr,
753 				      fib6_event->nrt6);
754 	if (IS_ERR(fib6_rt))
755 		return PTR_ERR(fib6_rt);
756 
757 	fib6_rt_old = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
758 	if (!fib6_rt_old)
759 		err = nsim_fib6_rt_add(data, fib6_rt);
760 	else
761 		err = nsim_fib6_rt_replace(data, fib6_rt, fib6_rt_old);
762 
763 	if (err)
764 		nsim_fib6_rt_destroy(fib6_rt);
765 
766 	return err;
767 }
768 
nsim_fib6_rt_remove(struct nsim_fib_data * data,struct nsim_fib6_event * fib6_event)769 static void nsim_fib6_rt_remove(struct nsim_fib_data *data,
770 				struct nsim_fib6_event *fib6_event)
771 {
772 	struct fib6_info *rt = fib6_event->rt_arr[0];
773 	struct nsim_fib6_rt *fib6_rt;
774 	int i;
775 
776 	/* Multipath routes are first added to the FIB trie and only then
777 	 * notified. If we vetoed the addition, we will get a delete
778 	 * notification for a route we do not have. Therefore, do not warn if
779 	 * route was not found.
780 	 */
781 	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
782 	if (!fib6_rt)
783 		return;
784 
785 	/* If not all the nexthops are deleted, then only reduce the nexthop
786 	 * group.
787 	 */
788 	if (fib6_event->nrt6 != fib6_rt->nhs) {
789 		for (i = 0; i < fib6_event->nrt6; i++)
790 			nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
791 		return;
792 	}
793 
794 	rhashtable_remove_fast(&data->fib_rt_ht, &fib6_rt->common.ht_node,
795 			       nsim_fib_rt_ht_params);
796 	nsim_fib6_rt_destroy(fib6_rt);
797 }
798 
nsim_fib6_event_init(struct nsim_fib6_event * fib6_event,struct fib6_entry_notifier_info * fen6_info)799 static int nsim_fib6_event_init(struct nsim_fib6_event *fib6_event,
800 				struct fib6_entry_notifier_info *fen6_info)
801 {
802 	struct fib6_info *rt = fen6_info->rt;
803 	struct fib6_info **rt_arr;
804 	struct fib6_info *iter;
805 	unsigned int nrt6;
806 	int i = 0;
807 
808 	nrt6 = fen6_info->nsiblings + 1;
809 
810 	rt_arr = kcalloc(nrt6, sizeof(struct fib6_info *), GFP_ATOMIC);
811 	if (!rt_arr)
812 		return -ENOMEM;
813 
814 	fib6_event->rt_arr = rt_arr;
815 	fib6_event->nrt6 = nrt6;
816 
817 	rt_arr[0] = rt;
818 	fib6_info_hold(rt);
819 
820 	if (!fen6_info->nsiblings)
821 		return 0;
822 
823 	list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
824 		if (i == fen6_info->nsiblings)
825 			break;
826 
827 		rt_arr[i + 1] = iter;
828 		fib6_info_hold(iter);
829 		i++;
830 	}
831 	WARN_ON_ONCE(i != fen6_info->nsiblings);
832 
833 	return 0;
834 }
835 
nsim_fib6_event_fini(struct nsim_fib6_event * fib6_event)836 static void nsim_fib6_event_fini(struct nsim_fib6_event *fib6_event)
837 {
838 	int i;
839 
840 	for (i = 0; i < fib6_event->nrt6; i++)
841 		nsim_rt6_release(fib6_event->rt_arr[i]);
842 	kfree(fib6_event->rt_arr);
843 }
844 
nsim_fib6_event(struct nsim_fib_data * data,struct nsim_fib6_event * fib6_event,unsigned long event)845 static int nsim_fib6_event(struct nsim_fib_data *data,
846 			   struct nsim_fib6_event *fib6_event,
847 			   unsigned long event)
848 {
849 	int err;
850 
851 	if (fib6_event->rt_arr[0]->fib6_src.plen)
852 		return 0;
853 
854 	switch (event) {
855 	case FIB_EVENT_ENTRY_REPLACE:
856 		err = nsim_fib6_rt_insert(data, fib6_event);
857 		if (err)
858 			goto err_rt_offload_failed_flag_set;
859 		break;
860 	case FIB_EVENT_ENTRY_APPEND:
861 		err = nsim_fib6_rt_append(data, fib6_event);
862 		if (err)
863 			goto err_rt_offload_failed_flag_set;
864 		break;
865 	case FIB_EVENT_ENTRY_DEL:
866 		nsim_fib6_rt_remove(data, fib6_event);
867 		break;
868 	default:
869 		break;
870 	}
871 
872 	return 0;
873 
874 err_rt_offload_failed_flag_set:
875 	nsim_fib6_rt_offload_failed_flag_set(data, fib6_event->rt_arr,
876 					     fib6_event->nrt6);
877 	return err;
878 }
879 
nsim_fib_event(struct nsim_fib_event * fib_event)880 static void nsim_fib_event(struct nsim_fib_event *fib_event)
881 {
882 	switch (fib_event->family) {
883 	case AF_INET:
884 		nsim_fib4_event(fib_event->data, &fib_event->fen_info,
885 				fib_event->event);
886 		fib_info_put(fib_event->fen_info.fi);
887 		break;
888 	case AF_INET6:
889 		nsim_fib6_event(fib_event->data, &fib_event->fib6_event,
890 				fib_event->event);
891 		nsim_fib6_event_fini(&fib_event->fib6_event);
892 		break;
893 	}
894 }
895 
nsim_fib4_prepare_event(struct fib_notifier_info * info,struct nsim_fib_event * fib_event,unsigned long event)896 static int nsim_fib4_prepare_event(struct fib_notifier_info *info,
897 				   struct nsim_fib_event *fib_event,
898 				   unsigned long event)
899 {
900 	struct nsim_fib_data *data = fib_event->data;
901 	struct fib_entry_notifier_info *fen_info;
902 	struct netlink_ext_ack *extack;
903 	int err = 0;
904 
905 	fen_info = container_of(info, struct fib_entry_notifier_info,
906 				info);
907 	fib_event->fen_info = *fen_info;
908 	extack = info->extack;
909 
910 	switch (event) {
911 	case FIB_EVENT_ENTRY_REPLACE:
912 		err = nsim_fib_account(&data->ipv4.fib, true);
913 		if (err) {
914 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
915 			return err;
916 		}
917 		break;
918 	case FIB_EVENT_ENTRY_DEL:
919 		if (data->fail_route_delete) {
920 			NL_SET_ERR_MSG_MOD(extack, "Failed to process route deletion");
921 			return -EINVAL;
922 		}
923 		nsim_fib_account(&data->ipv4.fib, false);
924 		break;
925 	}
926 
927 	/* Take reference on fib_info to prevent it from being
928 	 * freed while event is queued. Release it afterwards.
929 	 */
930 	fib_info_hold(fib_event->fen_info.fi);
931 
932 	return 0;
933 }
934 
nsim_fib6_prepare_event(struct fib_notifier_info * info,struct nsim_fib_event * fib_event,unsigned long event)935 static int nsim_fib6_prepare_event(struct fib_notifier_info *info,
936 				   struct nsim_fib_event *fib_event,
937 				   unsigned long event)
938 {
939 	struct nsim_fib_data *data = fib_event->data;
940 	struct fib6_entry_notifier_info *fen6_info;
941 	struct netlink_ext_ack *extack;
942 	int err = 0;
943 
944 	fen6_info = container_of(info, struct fib6_entry_notifier_info,
945 				 info);
946 
947 	err = nsim_fib6_event_init(&fib_event->fib6_event, fen6_info);
948 	if (err)
949 		return err;
950 
951 	extack = info->extack;
952 	switch (event) {
953 	case FIB_EVENT_ENTRY_REPLACE:
954 		err = nsim_fib_account(&data->ipv6.fib, true);
955 		if (err) {
956 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
957 			goto err_fib6_event_fini;
958 		}
959 		break;
960 	case FIB_EVENT_ENTRY_DEL:
961 		if (data->fail_route_delete) {
962 			err = -EINVAL;
963 			NL_SET_ERR_MSG_MOD(extack, "Failed to process route deletion");
964 			goto err_fib6_event_fini;
965 		}
966 		nsim_fib_account(&data->ipv6.fib, false);
967 		break;
968 	}
969 
970 	return 0;
971 
972 err_fib6_event_fini:
973 	nsim_fib6_event_fini(&fib_event->fib6_event);
974 	return err;
975 }
976 
nsim_fib_event_schedule_work(struct nsim_fib_data * data,struct fib_notifier_info * info,unsigned long event)977 static int nsim_fib_event_schedule_work(struct nsim_fib_data *data,
978 					struct fib_notifier_info *info,
979 					unsigned long event)
980 {
981 	struct nsim_fib_event *fib_event;
982 	int err;
983 
984 	if (info->family != AF_INET && info->family != AF_INET6)
985 		/* netdevsim does not support 'RTNL_FAMILY_IP6MR' and
986 		 * 'RTNL_FAMILY_IPMR' and should ignore them.
987 		 */
988 		return NOTIFY_DONE;
989 
990 	fib_event = kzalloc(sizeof(*fib_event), GFP_ATOMIC);
991 	if (!fib_event)
992 		goto err_fib_event_alloc;
993 
994 	fib_event->data = data;
995 	fib_event->event = event;
996 	fib_event->family = info->family;
997 
998 	switch (info->family) {
999 	case AF_INET:
1000 		err = nsim_fib4_prepare_event(info, fib_event, event);
1001 		break;
1002 	case AF_INET6:
1003 		err = nsim_fib6_prepare_event(info, fib_event, event);
1004 		break;
1005 	}
1006 
1007 	if (err)
1008 		goto err_fib_prepare_event;
1009 
1010 	/* Enqueue the event and trigger the work */
1011 	spin_lock_bh(&data->fib_event_queue_lock);
1012 	list_add_tail(&fib_event->list, &data->fib_event_queue);
1013 	spin_unlock_bh(&data->fib_event_queue_lock);
1014 	schedule_work(&data->fib_event_work);
1015 
1016 	return NOTIFY_DONE;
1017 
1018 err_fib_prepare_event:
1019 	kfree(fib_event);
1020 err_fib_event_alloc:
1021 	if (event == FIB_EVENT_ENTRY_DEL)
1022 		schedule_work(&data->fib_flush_work);
1023 	return NOTIFY_BAD;
1024 }
1025 
nsim_fib_event_nb(struct notifier_block * nb,unsigned long event,void * ptr)1026 static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
1027 			     void *ptr)
1028 {
1029 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1030 						  fib_nb);
1031 	struct fib_notifier_info *info = ptr;
1032 	int err;
1033 
1034 	switch (event) {
1035 	case FIB_EVENT_RULE_ADD:
1036 	case FIB_EVENT_RULE_DEL:
1037 		err = nsim_fib_rule_event(data, info,
1038 					  event == FIB_EVENT_RULE_ADD);
1039 		return notifier_from_errno(err);
1040 	case FIB_EVENT_ENTRY_REPLACE:
1041 	case FIB_EVENT_ENTRY_APPEND:
1042 	case FIB_EVENT_ENTRY_DEL:
1043 		return nsim_fib_event_schedule_work(data, info, event);
1044 	}
1045 
1046 	return NOTIFY_DONE;
1047 }
1048 
nsim_fib4_rt_free(struct nsim_fib_rt * fib_rt,struct nsim_fib_data * data)1049 static void nsim_fib4_rt_free(struct nsim_fib_rt *fib_rt,
1050 			      struct nsim_fib_data *data)
1051 {
1052 	struct devlink *devlink = data->devlink;
1053 	struct nsim_fib4_rt *fib4_rt;
1054 
1055 	fib4_rt = container_of(fib_rt, struct nsim_fib4_rt, common);
1056 	nsim_fib4_rt_hw_flags_set(devlink_net(devlink), fib4_rt, false);
1057 	nsim_fib_account(&data->ipv4.fib, false);
1058 	nsim_fib4_rt_destroy(fib4_rt);
1059 }
1060 
nsim_fib6_rt_free(struct nsim_fib_rt * fib_rt,struct nsim_fib_data * data)1061 static void nsim_fib6_rt_free(struct nsim_fib_rt *fib_rt,
1062 			      struct nsim_fib_data *data)
1063 {
1064 	struct nsim_fib6_rt *fib6_rt;
1065 
1066 	fib6_rt = container_of(fib_rt, struct nsim_fib6_rt, common);
1067 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, false);
1068 	nsim_fib_account(&data->ipv6.fib, false);
1069 	nsim_fib6_rt_destroy(fib6_rt);
1070 }
1071 
nsim_fib_rt_free(void * ptr,void * arg)1072 static void nsim_fib_rt_free(void *ptr, void *arg)
1073 {
1074 	struct nsim_fib_rt *fib_rt = ptr;
1075 	struct nsim_fib_data *data = arg;
1076 
1077 	switch (fib_rt->key.family) {
1078 	case AF_INET:
1079 		nsim_fib4_rt_free(fib_rt, data);
1080 		break;
1081 	case AF_INET6:
1082 		nsim_fib6_rt_free(fib_rt, data);
1083 		break;
1084 	default:
1085 		WARN_ON_ONCE(1);
1086 	}
1087 }
1088 
1089 /* inconsistent dump, trying again */
nsim_fib_dump_inconsistent(struct notifier_block * nb)1090 static void nsim_fib_dump_inconsistent(struct notifier_block *nb)
1091 {
1092 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1093 						  fib_nb);
1094 	struct nsim_fib_rt *fib_rt, *fib_rt_tmp;
1095 
1096 	/* Flush the work to make sure there is no race with notifications. */
1097 	flush_work(&data->fib_event_work);
1098 
1099 	/* The notifier block is still not registered, so we do not need to
1100 	 * take any locks here.
1101 	 */
1102 	list_for_each_entry_safe(fib_rt, fib_rt_tmp, &data->fib_rt_list, list) {
1103 		rhashtable_remove_fast(&data->fib_rt_ht, &fib_rt->ht_node,
1104 				       nsim_fib_rt_ht_params);
1105 		nsim_fib_rt_free(fib_rt, data);
1106 	}
1107 
1108 	atomic64_set(&data->ipv4.rules.num, 0ULL);
1109 	atomic64_set(&data->ipv6.rules.num, 0ULL);
1110 }
1111 
nsim_nexthop_create(struct nsim_fib_data * data,struct nh_notifier_info * info)1112 static struct nsim_nexthop *nsim_nexthop_create(struct nsim_fib_data *data,
1113 						struct nh_notifier_info *info)
1114 {
1115 	struct nsim_nexthop *nexthop;
1116 	u64 occ = 0;
1117 	int i;
1118 
1119 	nexthop = kzalloc(sizeof(*nexthop), GFP_KERNEL);
1120 	if (!nexthop)
1121 		return ERR_PTR(-ENOMEM);
1122 
1123 	nexthop->id = info->id;
1124 
1125 	/* Determine the number of nexthop entries the new nexthop will
1126 	 * occupy.
1127 	 */
1128 
1129 	switch (info->type) {
1130 	case NH_NOTIFIER_INFO_TYPE_SINGLE:
1131 		occ = 1;
1132 		break;
1133 	case NH_NOTIFIER_INFO_TYPE_GRP:
1134 		for (i = 0; i < info->nh_grp->num_nh; i++)
1135 			occ += info->nh_grp->nh_entries[i].weight;
1136 		break;
1137 	case NH_NOTIFIER_INFO_TYPE_RES_TABLE:
1138 		occ = info->nh_res_table->num_nh_buckets;
1139 		nexthop->is_resilient = true;
1140 		break;
1141 	default:
1142 		NL_SET_ERR_MSG_MOD(info->extack, "Unsupported nexthop type");
1143 		kfree(nexthop);
1144 		return ERR_PTR(-EOPNOTSUPP);
1145 	}
1146 
1147 	nexthop->occ = occ;
1148 	return nexthop;
1149 }
1150 
nsim_nexthop_destroy(struct nsim_nexthop * nexthop)1151 static void nsim_nexthop_destroy(struct nsim_nexthop *nexthop)
1152 {
1153 	kfree(nexthop);
1154 }
1155 
nsim_nexthop_account(struct nsim_fib_data * data,u64 occ,bool add,struct netlink_ext_ack * extack)1156 static int nsim_nexthop_account(struct nsim_fib_data *data, u64 occ,
1157 				bool add, struct netlink_ext_ack *extack)
1158 {
1159 	int i, err = 0;
1160 
1161 	if (add) {
1162 		for (i = 0; i < occ; i++)
1163 			if (!atomic64_add_unless(&data->nexthops.num, 1,
1164 						 data->nexthops.max)) {
1165 				err = -ENOSPC;
1166 				NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported nexthops");
1167 				goto err_num_decrease;
1168 			}
1169 	} else {
1170 		if (WARN_ON(occ > atomic64_read(&data->nexthops.num)))
1171 			return -EINVAL;
1172 		atomic64_sub(occ, &data->nexthops.num);
1173 	}
1174 
1175 	return err;
1176 
1177 err_num_decrease:
1178 	atomic64_sub(i, &data->nexthops.num);
1179 	return err;
1180 
1181 }
1182 
nsim_nexthop_hw_flags_set(struct net * net,const struct nsim_nexthop * nexthop,bool trap)1183 static void nsim_nexthop_hw_flags_set(struct net *net,
1184 				      const struct nsim_nexthop *nexthop,
1185 				      bool trap)
1186 {
1187 	int i;
1188 
1189 	nexthop_set_hw_flags(net, nexthop->id, false, trap);
1190 
1191 	if (!nexthop->is_resilient)
1192 		return;
1193 
1194 	for (i = 0; i < nexthop->occ; i++)
1195 		nexthop_bucket_set_hw_flags(net, nexthop->id, i, false, trap);
1196 }
1197 
nsim_nexthop_add(struct nsim_fib_data * data,struct nsim_nexthop * nexthop,struct netlink_ext_ack * extack)1198 static int nsim_nexthop_add(struct nsim_fib_data *data,
1199 			    struct nsim_nexthop *nexthop,
1200 			    struct netlink_ext_ack *extack)
1201 {
1202 	struct net *net = devlink_net(data->devlink);
1203 	int err;
1204 
1205 	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
1206 	if (err)
1207 		return err;
1208 
1209 	err = rhashtable_insert_fast(&data->nexthop_ht, &nexthop->ht_node,
1210 				     nsim_nexthop_ht_params);
1211 	if (err) {
1212 		NL_SET_ERR_MSG_MOD(extack, "Failed to insert nexthop");
1213 		goto err_nexthop_dismiss;
1214 	}
1215 
1216 	nsim_nexthop_hw_flags_set(net, nexthop, true);
1217 
1218 	return 0;
1219 
1220 err_nexthop_dismiss:
1221 	nsim_nexthop_account(data, nexthop->occ, false, extack);
1222 	return err;
1223 }
1224 
nsim_nexthop_replace(struct nsim_fib_data * data,struct nsim_nexthop * nexthop,struct nsim_nexthop * nexthop_old,struct netlink_ext_ack * extack)1225 static int nsim_nexthop_replace(struct nsim_fib_data *data,
1226 				struct nsim_nexthop *nexthop,
1227 				struct nsim_nexthop *nexthop_old,
1228 				struct netlink_ext_ack *extack)
1229 {
1230 	struct net *net = devlink_net(data->devlink);
1231 	int err;
1232 
1233 	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
1234 	if (err)
1235 		return err;
1236 
1237 	err = rhashtable_replace_fast(&data->nexthop_ht,
1238 				      &nexthop_old->ht_node, &nexthop->ht_node,
1239 				      nsim_nexthop_ht_params);
1240 	if (err) {
1241 		NL_SET_ERR_MSG_MOD(extack, "Failed to replace nexthop");
1242 		goto err_nexthop_dismiss;
1243 	}
1244 
1245 	nsim_nexthop_hw_flags_set(net, nexthop, true);
1246 	nsim_nexthop_account(data, nexthop_old->occ, false, extack);
1247 	nsim_nexthop_destroy(nexthop_old);
1248 
1249 	return 0;
1250 
1251 err_nexthop_dismiss:
1252 	nsim_nexthop_account(data, nexthop->occ, false, extack);
1253 	return err;
1254 }
1255 
nsim_nexthop_insert(struct nsim_fib_data * data,struct nh_notifier_info * info)1256 static int nsim_nexthop_insert(struct nsim_fib_data *data,
1257 			       struct nh_notifier_info *info)
1258 {
1259 	struct nsim_nexthop *nexthop, *nexthop_old;
1260 	int err;
1261 
1262 	nexthop = nsim_nexthop_create(data, info);
1263 	if (IS_ERR(nexthop))
1264 		return PTR_ERR(nexthop);
1265 
1266 	nexthop_old = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
1267 					     nsim_nexthop_ht_params);
1268 	if (!nexthop_old)
1269 		err = nsim_nexthop_add(data, nexthop, info->extack);
1270 	else
1271 		err = nsim_nexthop_replace(data, nexthop, nexthop_old,
1272 					   info->extack);
1273 
1274 	if (err)
1275 		nsim_nexthop_destroy(nexthop);
1276 
1277 	return err;
1278 }
1279 
nsim_nexthop_remove(struct nsim_fib_data * data,struct nh_notifier_info * info)1280 static void nsim_nexthop_remove(struct nsim_fib_data *data,
1281 				struct nh_notifier_info *info)
1282 {
1283 	struct nsim_nexthop *nexthop;
1284 
1285 	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
1286 					 nsim_nexthop_ht_params);
1287 	if (!nexthop)
1288 		return;
1289 
1290 	rhashtable_remove_fast(&data->nexthop_ht, &nexthop->ht_node,
1291 			       nsim_nexthop_ht_params);
1292 	nsim_nexthop_account(data, nexthop->occ, false, info->extack);
1293 	nsim_nexthop_destroy(nexthop);
1294 }
1295 
nsim_nexthop_res_table_pre_replace(struct nsim_fib_data * data,struct nh_notifier_info * info)1296 static int nsim_nexthop_res_table_pre_replace(struct nsim_fib_data *data,
1297 					      struct nh_notifier_info *info)
1298 {
1299 	if (data->fail_res_nexthop_group_replace) {
1300 		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace a resilient nexthop group");
1301 		return -EINVAL;
1302 	}
1303 
1304 	return 0;
1305 }
1306 
nsim_nexthop_bucket_replace(struct nsim_fib_data * data,struct nh_notifier_info * info)1307 static int nsim_nexthop_bucket_replace(struct nsim_fib_data *data,
1308 				       struct nh_notifier_info *info)
1309 {
1310 	if (data->fail_nexthop_bucket_replace) {
1311 		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace nexthop bucket");
1312 		return -EINVAL;
1313 	}
1314 
1315 	nexthop_bucket_set_hw_flags(info->net, info->id,
1316 				    info->nh_res_bucket->bucket_index,
1317 				    false, true);
1318 
1319 	return 0;
1320 }
1321 
nsim_nexthop_event_nb(struct notifier_block * nb,unsigned long event,void * ptr)1322 static int nsim_nexthop_event_nb(struct notifier_block *nb, unsigned long event,
1323 				 void *ptr)
1324 {
1325 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1326 						  nexthop_nb);
1327 	struct nh_notifier_info *info = ptr;
1328 	int err = 0;
1329 
1330 	mutex_lock(&data->nh_lock);
1331 	switch (event) {
1332 	case NEXTHOP_EVENT_REPLACE:
1333 		err = nsim_nexthop_insert(data, info);
1334 		break;
1335 	case NEXTHOP_EVENT_DEL:
1336 		nsim_nexthop_remove(data, info);
1337 		break;
1338 	case NEXTHOP_EVENT_RES_TABLE_PRE_REPLACE:
1339 		err = nsim_nexthop_res_table_pre_replace(data, info);
1340 		break;
1341 	case NEXTHOP_EVENT_BUCKET_REPLACE:
1342 		err = nsim_nexthop_bucket_replace(data, info);
1343 		break;
1344 	default:
1345 		break;
1346 	}
1347 
1348 	mutex_unlock(&data->nh_lock);
1349 	return notifier_from_errno(err);
1350 }
1351 
nsim_nexthop_free(void * ptr,void * arg)1352 static void nsim_nexthop_free(void *ptr, void *arg)
1353 {
1354 	struct nsim_nexthop *nexthop = ptr;
1355 	struct nsim_fib_data *data = arg;
1356 	struct net *net;
1357 
1358 	net = devlink_net(data->devlink);
1359 	nsim_nexthop_hw_flags_set(net, nexthop, false);
1360 	nsim_nexthop_account(data, nexthop->occ, false, NULL);
1361 	nsim_nexthop_destroy(nexthop);
1362 }
1363 
nsim_nexthop_bucket_activity_write(struct file * file,const char __user * user_buf,size_t size,loff_t * ppos)1364 static ssize_t nsim_nexthop_bucket_activity_write(struct file *file,
1365 						  const char __user *user_buf,
1366 						  size_t size, loff_t *ppos)
1367 {
1368 	struct nsim_fib_data *data = file->private_data;
1369 	struct net *net = devlink_net(data->devlink);
1370 	struct nsim_nexthop *nexthop;
1371 	unsigned long *activity;
1372 	loff_t pos = *ppos;
1373 	u16 bucket_index;
1374 	char buf[128];
1375 	int err = 0;
1376 	u32 nhid;
1377 
1378 	if (pos != 0)
1379 		return -EINVAL;
1380 	if (size > sizeof(buf))
1381 		return -EINVAL;
1382 	if (copy_from_user(buf, user_buf, size))
1383 		return -EFAULT;
1384 	if (sscanf(buf, "%u %hu", &nhid, &bucket_index) != 2)
1385 		return -EINVAL;
1386 
1387 	rtnl_lock();
1388 
1389 	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &nhid,
1390 					 nsim_nexthop_ht_params);
1391 	if (!nexthop || !nexthop->is_resilient ||
1392 	    bucket_index >= nexthop->occ) {
1393 		err = -EINVAL;
1394 		goto out;
1395 	}
1396 
1397 	activity = bitmap_zalloc(nexthop->occ, GFP_KERNEL);
1398 	if (!activity) {
1399 		err = -ENOMEM;
1400 		goto out;
1401 	}
1402 
1403 	bitmap_set(activity, bucket_index, 1);
1404 	nexthop_res_grp_activity_update(net, nhid, nexthop->occ, activity);
1405 	bitmap_free(activity);
1406 
1407 out:
1408 	rtnl_unlock();
1409 
1410 	*ppos = size;
1411 	return err ?: size;
1412 }
1413 
1414 static const struct file_operations nsim_nexthop_bucket_activity_fops = {
1415 	.open = simple_open,
1416 	.write = nsim_nexthop_bucket_activity_write,
1417 	.llseek = no_llseek,
1418 	.owner = THIS_MODULE,
1419 };
1420 
nsim_fib_ipv4_resource_occ_get(void * priv)1421 static u64 nsim_fib_ipv4_resource_occ_get(void *priv)
1422 {
1423 	struct nsim_fib_data *data = priv;
1424 
1425 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB, false);
1426 }
1427 
nsim_fib_ipv4_rules_res_occ_get(void * priv)1428 static u64 nsim_fib_ipv4_rules_res_occ_get(void *priv)
1429 {
1430 	struct nsim_fib_data *data = priv;
1431 
1432 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB_RULES, false);
1433 }
1434 
nsim_fib_ipv6_resource_occ_get(void * priv)1435 static u64 nsim_fib_ipv6_resource_occ_get(void *priv)
1436 {
1437 	struct nsim_fib_data *data = priv;
1438 
1439 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB, false);
1440 }
1441 
nsim_fib_ipv6_rules_res_occ_get(void * priv)1442 static u64 nsim_fib_ipv6_rules_res_occ_get(void *priv)
1443 {
1444 	struct nsim_fib_data *data = priv;
1445 
1446 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB_RULES, false);
1447 }
1448 
nsim_fib_nexthops_res_occ_get(void * priv)1449 static u64 nsim_fib_nexthops_res_occ_get(void *priv)
1450 {
1451 	struct nsim_fib_data *data = priv;
1452 
1453 	return nsim_fib_get_val(data, NSIM_RESOURCE_NEXTHOPS, false);
1454 }
1455 
nsim_fib_set_max_all(struct nsim_fib_data * data,struct devlink * devlink)1456 static void nsim_fib_set_max_all(struct nsim_fib_data *data,
1457 				 struct devlink *devlink)
1458 {
1459 	static const enum nsim_resource_id res_ids[] = {
1460 		NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES,
1461 		NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES,
1462 		NSIM_RESOURCE_NEXTHOPS,
1463 	};
1464 	int i;
1465 
1466 	for (i = 0; i < ARRAY_SIZE(res_ids); i++) {
1467 		int err;
1468 		u64 val;
1469 
1470 		err = devl_resource_size_get(devlink, res_ids[i], &val);
1471 		if (err)
1472 			val = (u64) -1;
1473 		nsim_fib_set_max(data, res_ids[i], val);
1474 	}
1475 }
1476 
nsim_fib_event_work(struct work_struct * work)1477 static void nsim_fib_event_work(struct work_struct *work)
1478 {
1479 	struct nsim_fib_data *data = container_of(work, struct nsim_fib_data,
1480 						  fib_event_work);
1481 	struct nsim_fib_event *fib_event, *next_fib_event;
1482 
1483 	LIST_HEAD(fib_event_queue);
1484 
1485 	spin_lock_bh(&data->fib_event_queue_lock);
1486 	list_splice_init(&data->fib_event_queue, &fib_event_queue);
1487 	spin_unlock_bh(&data->fib_event_queue_lock);
1488 
1489 	mutex_lock(&data->fib_lock);
1490 	list_for_each_entry_safe(fib_event, next_fib_event, &fib_event_queue,
1491 				 list) {
1492 		nsim_fib_event(fib_event);
1493 		list_del(&fib_event->list);
1494 		kfree(fib_event);
1495 		cond_resched();
1496 	}
1497 	mutex_unlock(&data->fib_lock);
1498 }
1499 
nsim_fib_flush_work(struct work_struct * work)1500 static void nsim_fib_flush_work(struct work_struct *work)
1501 {
1502 	struct nsim_fib_data *data = container_of(work, struct nsim_fib_data,
1503 						  fib_flush_work);
1504 	struct nsim_fib_rt *fib_rt, *fib_rt_tmp;
1505 
1506 	/* Process pending work. */
1507 	flush_work(&data->fib_event_work);
1508 
1509 	mutex_lock(&data->fib_lock);
1510 	list_for_each_entry_safe(fib_rt, fib_rt_tmp, &data->fib_rt_list, list) {
1511 		rhashtable_remove_fast(&data->fib_rt_ht, &fib_rt->ht_node,
1512 				       nsim_fib_rt_ht_params);
1513 		nsim_fib_rt_free(fib_rt, data);
1514 	}
1515 	mutex_unlock(&data->fib_lock);
1516 }
1517 
1518 static int
nsim_fib_debugfs_init(struct nsim_fib_data * data,struct nsim_dev * nsim_dev)1519 nsim_fib_debugfs_init(struct nsim_fib_data *data, struct nsim_dev *nsim_dev)
1520 {
1521 	data->ddir = debugfs_create_dir("fib", nsim_dev->ddir);
1522 	if (IS_ERR(data->ddir))
1523 		return PTR_ERR(data->ddir);
1524 
1525 	data->fail_route_offload = false;
1526 	debugfs_create_bool("fail_route_offload", 0600, data->ddir,
1527 			    &data->fail_route_offload);
1528 
1529 	data->fail_res_nexthop_group_replace = false;
1530 	debugfs_create_bool("fail_res_nexthop_group_replace", 0600, data->ddir,
1531 			    &data->fail_res_nexthop_group_replace);
1532 
1533 	data->fail_nexthop_bucket_replace = false;
1534 	debugfs_create_bool("fail_nexthop_bucket_replace", 0600, data->ddir,
1535 			    &data->fail_nexthop_bucket_replace);
1536 
1537 	debugfs_create_file("nexthop_bucket_activity", 0200, data->ddir,
1538 			    data, &nsim_nexthop_bucket_activity_fops);
1539 
1540 	data->fail_route_delete = false;
1541 	debugfs_create_bool("fail_route_delete", 0600, data->ddir,
1542 			    &data->fail_route_delete);
1543 	return 0;
1544 }
1545 
nsim_fib_debugfs_exit(struct nsim_fib_data * data)1546 static void nsim_fib_debugfs_exit(struct nsim_fib_data *data)
1547 {
1548 	debugfs_remove_recursive(data->ddir);
1549 }
1550 
nsim_fib_create(struct devlink * devlink,struct netlink_ext_ack * extack)1551 struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
1552 				      struct netlink_ext_ack *extack)
1553 {
1554 	struct nsim_fib_data *data;
1555 	struct nsim_dev *nsim_dev;
1556 	int err;
1557 
1558 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1559 	if (!data)
1560 		return ERR_PTR(-ENOMEM);
1561 	data->devlink = devlink;
1562 
1563 	nsim_dev = devlink_priv(devlink);
1564 	err = nsim_fib_debugfs_init(data, nsim_dev);
1565 	if (err)
1566 		goto err_data_free;
1567 
1568 	mutex_init(&data->nh_lock);
1569 	err = rhashtable_init(&data->nexthop_ht, &nsim_nexthop_ht_params);
1570 	if (err)
1571 		goto err_debugfs_exit;
1572 
1573 	mutex_init(&data->fib_lock);
1574 	INIT_LIST_HEAD(&data->fib_rt_list);
1575 	err = rhashtable_init(&data->fib_rt_ht, &nsim_fib_rt_ht_params);
1576 	if (err)
1577 		goto err_rhashtable_nexthop_destroy;
1578 
1579 	INIT_WORK(&data->fib_event_work, nsim_fib_event_work);
1580 	INIT_WORK(&data->fib_flush_work, nsim_fib_flush_work);
1581 	INIT_LIST_HEAD(&data->fib_event_queue);
1582 	spin_lock_init(&data->fib_event_queue_lock);
1583 
1584 	nsim_fib_set_max_all(data, devlink);
1585 
1586 	data->nexthop_nb.notifier_call = nsim_nexthop_event_nb;
1587 	err = register_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb,
1588 					extack);
1589 	if (err) {
1590 		pr_err("Failed to register nexthop notifier\n");
1591 		goto err_rhashtable_fib_destroy;
1592 	}
1593 
1594 	data->fib_nb.notifier_call = nsim_fib_event_nb;
1595 	err = register_fib_notifier(devlink_net(devlink), &data->fib_nb,
1596 				    nsim_fib_dump_inconsistent, extack);
1597 	if (err) {
1598 		pr_err("Failed to register fib notifier\n");
1599 		goto err_nexthop_nb_unregister;
1600 	}
1601 
1602 	devl_resource_occ_get_register(devlink,
1603 				       NSIM_RESOURCE_IPV4_FIB,
1604 				       nsim_fib_ipv4_resource_occ_get,
1605 				       data);
1606 	devl_resource_occ_get_register(devlink,
1607 				       NSIM_RESOURCE_IPV4_FIB_RULES,
1608 				       nsim_fib_ipv4_rules_res_occ_get,
1609 				       data);
1610 	devl_resource_occ_get_register(devlink,
1611 				       NSIM_RESOURCE_IPV6_FIB,
1612 				       nsim_fib_ipv6_resource_occ_get,
1613 				       data);
1614 	devl_resource_occ_get_register(devlink,
1615 				       NSIM_RESOURCE_IPV6_FIB_RULES,
1616 				       nsim_fib_ipv6_rules_res_occ_get,
1617 				       data);
1618 	devl_resource_occ_get_register(devlink,
1619 				       NSIM_RESOURCE_NEXTHOPS,
1620 				       nsim_fib_nexthops_res_occ_get,
1621 				       data);
1622 	return data;
1623 
1624 err_nexthop_nb_unregister:
1625 	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
1626 err_rhashtable_fib_destroy:
1627 	cancel_work_sync(&data->fib_flush_work);
1628 	flush_work(&data->fib_event_work);
1629 	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
1630 				    data);
1631 err_rhashtable_nexthop_destroy:
1632 	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
1633 				    data);
1634 	mutex_destroy(&data->fib_lock);
1635 err_debugfs_exit:
1636 	mutex_destroy(&data->nh_lock);
1637 	nsim_fib_debugfs_exit(data);
1638 err_data_free:
1639 	kfree(data);
1640 	return ERR_PTR(err);
1641 }
1642 
nsim_fib_destroy(struct devlink * devlink,struct nsim_fib_data * data)1643 void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *data)
1644 {
1645 	devl_resource_occ_get_unregister(devlink,
1646 					 NSIM_RESOURCE_NEXTHOPS);
1647 	devl_resource_occ_get_unregister(devlink,
1648 					 NSIM_RESOURCE_IPV6_FIB_RULES);
1649 	devl_resource_occ_get_unregister(devlink,
1650 					 NSIM_RESOURCE_IPV6_FIB);
1651 	devl_resource_occ_get_unregister(devlink,
1652 					 NSIM_RESOURCE_IPV4_FIB_RULES);
1653 	devl_resource_occ_get_unregister(devlink,
1654 					 NSIM_RESOURCE_IPV4_FIB);
1655 	unregister_fib_notifier(devlink_net(devlink), &data->fib_nb);
1656 	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
1657 	cancel_work_sync(&data->fib_flush_work);
1658 	flush_work(&data->fib_event_work);
1659 	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
1660 				    data);
1661 	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
1662 				    data);
1663 	WARN_ON_ONCE(!list_empty(&data->fib_event_queue));
1664 	WARN_ON_ONCE(!list_empty(&data->fib_rt_list));
1665 	mutex_destroy(&data->fib_lock);
1666 	mutex_destroy(&data->nh_lock);
1667 	nsim_fib_debugfs_exit(data);
1668 	kfree(data);
1669 }
1670