xref: /openbmc/linux/drivers/net/netdevsim/fib.c (revision 2dd6532e)
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 list_head fib_event_queue;
58 	spinlock_t fib_event_queue_lock; /* Protects fib event queue list */
59 	struct mutex nh_lock; /* Protects NH HT */
60 	struct dentry *ddir;
61 	bool fail_route_offload;
62 	bool fail_res_nexthop_group_replace;
63 	bool fail_nexthop_bucket_replace;
64 };
65 
66 struct nsim_fib_rt_key {
67 	unsigned char addr[sizeof(struct in6_addr)];
68 	unsigned char prefix_len;
69 	int family;
70 	u32 tb_id;
71 };
72 
73 struct nsim_fib_rt {
74 	struct nsim_fib_rt_key key;
75 	struct rhash_head ht_node;
76 	struct list_head list;	/* Member of fib_rt_list */
77 };
78 
79 struct nsim_fib4_rt {
80 	struct nsim_fib_rt common;
81 	struct fib_info *fi;
82 	dscp_t dscp;
83 	u8 type;
84 };
85 
86 struct nsim_fib6_rt {
87 	struct nsim_fib_rt common;
88 	struct list_head nh_list;
89 	unsigned int nhs;
90 };
91 
92 struct nsim_fib6_rt_nh {
93 	struct list_head list;	/* Member of nh_list */
94 	struct fib6_info *rt;
95 };
96 
97 struct nsim_fib6_event {
98 	struct fib6_info **rt_arr;
99 	unsigned int nrt6;
100 };
101 
102 struct nsim_fib_event {
103 	struct list_head list; /* node in fib queue */
104 	union {
105 		struct fib_entry_notifier_info fen_info;
106 		struct nsim_fib6_event fib6_event;
107 	};
108 	struct nsim_fib_data *data;
109 	unsigned long event;
110 	int family;
111 };
112 
113 static const struct rhashtable_params nsim_fib_rt_ht_params = {
114 	.key_offset = offsetof(struct nsim_fib_rt, key),
115 	.head_offset = offsetof(struct nsim_fib_rt, ht_node),
116 	.key_len = sizeof(struct nsim_fib_rt_key),
117 	.automatic_shrinking = true,
118 };
119 
120 struct nsim_nexthop {
121 	struct rhash_head ht_node;
122 	u64 occ;
123 	u32 id;
124 	bool is_resilient;
125 };
126 
127 static const struct rhashtable_params nsim_nexthop_ht_params = {
128 	.key_offset = offsetof(struct nsim_nexthop, id),
129 	.head_offset = offsetof(struct nsim_nexthop, ht_node),
130 	.key_len = sizeof(u32),
131 	.automatic_shrinking = true,
132 };
133 
134 u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
135 		     enum nsim_resource_id res_id, bool max)
136 {
137 	struct nsim_fib_entry *entry;
138 
139 	switch (res_id) {
140 	case NSIM_RESOURCE_IPV4_FIB:
141 		entry = &fib_data->ipv4.fib;
142 		break;
143 	case NSIM_RESOURCE_IPV4_FIB_RULES:
144 		entry = &fib_data->ipv4.rules;
145 		break;
146 	case NSIM_RESOURCE_IPV6_FIB:
147 		entry = &fib_data->ipv6.fib;
148 		break;
149 	case NSIM_RESOURCE_IPV6_FIB_RULES:
150 		entry = &fib_data->ipv6.rules;
151 		break;
152 	case NSIM_RESOURCE_NEXTHOPS:
153 		entry = &fib_data->nexthops;
154 		break;
155 	default:
156 		return 0;
157 	}
158 
159 	return max ? entry->max : atomic64_read(&entry->num);
160 }
161 
162 static void nsim_fib_set_max(struct nsim_fib_data *fib_data,
163 			     enum nsim_resource_id res_id, u64 val)
164 {
165 	struct nsim_fib_entry *entry;
166 
167 	switch (res_id) {
168 	case NSIM_RESOURCE_IPV4_FIB:
169 		entry = &fib_data->ipv4.fib;
170 		break;
171 	case NSIM_RESOURCE_IPV4_FIB_RULES:
172 		entry = &fib_data->ipv4.rules;
173 		break;
174 	case NSIM_RESOURCE_IPV6_FIB:
175 		entry = &fib_data->ipv6.fib;
176 		break;
177 	case NSIM_RESOURCE_IPV6_FIB_RULES:
178 		entry = &fib_data->ipv6.rules;
179 		break;
180 	case NSIM_RESOURCE_NEXTHOPS:
181 		entry = &fib_data->nexthops;
182 		break;
183 	default:
184 		WARN_ON(1);
185 		return;
186 	}
187 	entry->max = val;
188 }
189 
190 static int nsim_fib_rule_account(struct nsim_fib_entry *entry, bool add,
191 				 struct netlink_ext_ack *extack)
192 {
193 	int err = 0;
194 
195 	if (add) {
196 		if (!atomic64_add_unless(&entry->num, 1, entry->max)) {
197 			err = -ENOSPC;
198 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib rule entries");
199 		}
200 	} else {
201 		atomic64_dec_if_positive(&entry->num);
202 	}
203 
204 	return err;
205 }
206 
207 static int nsim_fib_rule_event(struct nsim_fib_data *data,
208 			       struct fib_notifier_info *info, bool add)
209 {
210 	struct netlink_ext_ack *extack = info->extack;
211 	int err = 0;
212 
213 	switch (info->family) {
214 	case AF_INET:
215 		err = nsim_fib_rule_account(&data->ipv4.rules, add, extack);
216 		break;
217 	case AF_INET6:
218 		err = nsim_fib_rule_account(&data->ipv6.rules, add, extack);
219 		break;
220 	}
221 
222 	return err;
223 }
224 
225 static int nsim_fib_account(struct nsim_fib_entry *entry, bool add)
226 {
227 	int err = 0;
228 
229 	if (add) {
230 		if (!atomic64_add_unless(&entry->num, 1, entry->max))
231 			err = -ENOSPC;
232 	} else {
233 		atomic64_dec_if_positive(&entry->num);
234 	}
235 
236 	return err;
237 }
238 
239 static void nsim_fib_rt_init(struct nsim_fib_data *data,
240 			     struct nsim_fib_rt *fib_rt, const void *addr,
241 			     size_t addr_len, unsigned int prefix_len,
242 			     int family, u32 tb_id)
243 {
244 	memcpy(fib_rt->key.addr, addr, addr_len);
245 	fib_rt->key.prefix_len = prefix_len;
246 	fib_rt->key.family = family;
247 	fib_rt->key.tb_id = tb_id;
248 	list_add(&fib_rt->list, &data->fib_rt_list);
249 }
250 
251 static void nsim_fib_rt_fini(struct nsim_fib_rt *fib_rt)
252 {
253 	list_del(&fib_rt->list);
254 }
255 
256 static struct nsim_fib_rt *nsim_fib_rt_lookup(struct rhashtable *fib_rt_ht,
257 					      const void *addr, size_t addr_len,
258 					      unsigned int prefix_len,
259 					      int family, u32 tb_id)
260 {
261 	struct nsim_fib_rt_key key;
262 
263 	memset(&key, 0, sizeof(key));
264 	memcpy(key.addr, addr, addr_len);
265 	key.prefix_len = prefix_len;
266 	key.family = family;
267 	key.tb_id = tb_id;
268 
269 	return rhashtable_lookup_fast(fib_rt_ht, &key, nsim_fib_rt_ht_params);
270 }
271 
272 static struct nsim_fib4_rt *
273 nsim_fib4_rt_create(struct nsim_fib_data *data,
274 		    struct fib_entry_notifier_info *fen_info)
275 {
276 	struct nsim_fib4_rt *fib4_rt;
277 
278 	fib4_rt = kzalloc(sizeof(*fib4_rt), GFP_KERNEL);
279 	if (!fib4_rt)
280 		return NULL;
281 
282 	nsim_fib_rt_init(data, &fib4_rt->common, &fen_info->dst, sizeof(u32),
283 			 fen_info->dst_len, AF_INET, fen_info->tb_id);
284 
285 	fib4_rt->fi = fen_info->fi;
286 	fib_info_hold(fib4_rt->fi);
287 	fib4_rt->dscp = fen_info->dscp;
288 	fib4_rt->type = fen_info->type;
289 
290 	return fib4_rt;
291 }
292 
293 static void nsim_fib4_rt_destroy(struct nsim_fib4_rt *fib4_rt)
294 {
295 	fib_info_put(fib4_rt->fi);
296 	nsim_fib_rt_fini(&fib4_rt->common);
297 	kfree(fib4_rt);
298 }
299 
300 static struct nsim_fib4_rt *
301 nsim_fib4_rt_lookup(struct rhashtable *fib_rt_ht,
302 		    const struct fib_entry_notifier_info *fen_info)
303 {
304 	struct nsim_fib_rt *fib_rt;
305 
306 	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &fen_info->dst, sizeof(u32),
307 				    fen_info->dst_len, AF_INET,
308 				    fen_info->tb_id);
309 	if (!fib_rt)
310 		return NULL;
311 
312 	return container_of(fib_rt, struct nsim_fib4_rt, common);
313 }
314 
315 static void
316 nsim_fib4_rt_offload_failed_flag_set(struct net *net,
317 				     struct fib_entry_notifier_info *fen_info)
318 {
319 	u32 *p_dst = (u32 *)&fen_info->dst;
320 	struct fib_rt_info fri;
321 
322 	fri.fi = fen_info->fi;
323 	fri.tb_id = fen_info->tb_id;
324 	fri.dst = cpu_to_be32(*p_dst);
325 	fri.dst_len = fen_info->dst_len;
326 	fri.dscp = fen_info->dscp;
327 	fri.type = fen_info->type;
328 	fri.offload = false;
329 	fri.trap = false;
330 	fri.offload_failed = true;
331 	fib_alias_hw_flags_set(net, &fri);
332 }
333 
334 static void nsim_fib4_rt_hw_flags_set(struct net *net,
335 				      const struct nsim_fib4_rt *fib4_rt,
336 				      bool trap)
337 {
338 	u32 *p_dst = (u32 *) fib4_rt->common.key.addr;
339 	int dst_len = fib4_rt->common.key.prefix_len;
340 	struct fib_rt_info fri;
341 
342 	fri.fi = fib4_rt->fi;
343 	fri.tb_id = fib4_rt->common.key.tb_id;
344 	fri.dst = cpu_to_be32(*p_dst);
345 	fri.dst_len = dst_len;
346 	fri.dscp = fib4_rt->dscp;
347 	fri.type = fib4_rt->type;
348 	fri.offload = false;
349 	fri.trap = trap;
350 	fri.offload_failed = false;
351 	fib_alias_hw_flags_set(net, &fri);
352 }
353 
354 static int nsim_fib4_rt_add(struct nsim_fib_data *data,
355 			    struct nsim_fib4_rt *fib4_rt)
356 {
357 	struct net *net = devlink_net(data->devlink);
358 	int err;
359 
360 	err = rhashtable_insert_fast(&data->fib_rt_ht,
361 				     &fib4_rt->common.ht_node,
362 				     nsim_fib_rt_ht_params);
363 	if (err)
364 		goto err_fib_dismiss;
365 
366 	/* Simulate hardware programming latency. */
367 	msleep(1);
368 	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
369 
370 	return 0;
371 
372 err_fib_dismiss:
373 	/* Drop the accounting that was increased from the notification
374 	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
375 	 */
376 	nsim_fib_account(&data->ipv4.fib, false);
377 	return err;
378 }
379 
380 static int nsim_fib4_rt_replace(struct nsim_fib_data *data,
381 				struct nsim_fib4_rt *fib4_rt,
382 				struct nsim_fib4_rt *fib4_rt_old)
383 {
384 	struct net *net = devlink_net(data->devlink);
385 	int err;
386 
387 	/* We are replacing a route, so need to remove the accounting which
388 	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
389 	 */
390 	err = nsim_fib_account(&data->ipv4.fib, false);
391 	if (err)
392 		return err;
393 	err = rhashtable_replace_fast(&data->fib_rt_ht,
394 				      &fib4_rt_old->common.ht_node,
395 				      &fib4_rt->common.ht_node,
396 				      nsim_fib_rt_ht_params);
397 	if (err)
398 		return err;
399 
400 	msleep(1);
401 	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
402 
403 	nsim_fib4_rt_hw_flags_set(net, fib4_rt_old, false);
404 	nsim_fib4_rt_destroy(fib4_rt_old);
405 
406 	return 0;
407 }
408 
409 static int nsim_fib4_rt_insert(struct nsim_fib_data *data,
410 			       struct fib_entry_notifier_info *fen_info)
411 {
412 	struct nsim_fib4_rt *fib4_rt, *fib4_rt_old;
413 	int err;
414 
415 	if (data->fail_route_offload) {
416 		/* For testing purposes, user set debugfs fail_route_offload
417 		 * value to true. Simulate hardware programming latency and then
418 		 * fail.
419 		 */
420 		msleep(1);
421 		return -EINVAL;
422 	}
423 
424 	fib4_rt = nsim_fib4_rt_create(data, fen_info);
425 	if (!fib4_rt)
426 		return -ENOMEM;
427 
428 	fib4_rt_old = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
429 	if (!fib4_rt_old)
430 		err = nsim_fib4_rt_add(data, fib4_rt);
431 	else
432 		err = nsim_fib4_rt_replace(data, fib4_rt, fib4_rt_old);
433 
434 	if (err)
435 		nsim_fib4_rt_destroy(fib4_rt);
436 
437 	return err;
438 }
439 
440 static void nsim_fib4_rt_remove(struct nsim_fib_data *data,
441 				const struct fib_entry_notifier_info *fen_info)
442 {
443 	struct nsim_fib4_rt *fib4_rt;
444 
445 	fib4_rt = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
446 	if (!fib4_rt)
447 		return;
448 
449 	rhashtable_remove_fast(&data->fib_rt_ht, &fib4_rt->common.ht_node,
450 			       nsim_fib_rt_ht_params);
451 	nsim_fib4_rt_destroy(fib4_rt);
452 }
453 
454 static int nsim_fib4_event(struct nsim_fib_data *data,
455 			   struct fib_entry_notifier_info *fen_info,
456 			   unsigned long event)
457 {
458 	int err = 0;
459 
460 	switch (event) {
461 	case FIB_EVENT_ENTRY_REPLACE:
462 		err = nsim_fib4_rt_insert(data, fen_info);
463 		if (err) {
464 			struct net *net = devlink_net(data->devlink);
465 
466 			nsim_fib4_rt_offload_failed_flag_set(net, fen_info);
467 		}
468 		break;
469 	case FIB_EVENT_ENTRY_DEL:
470 		nsim_fib4_rt_remove(data, fen_info);
471 		break;
472 	default:
473 		break;
474 	}
475 
476 	return err;
477 }
478 
479 static struct nsim_fib6_rt_nh *
480 nsim_fib6_rt_nh_find(const struct nsim_fib6_rt *fib6_rt,
481 		     const struct fib6_info *rt)
482 {
483 	struct nsim_fib6_rt_nh *fib6_rt_nh;
484 
485 	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list) {
486 		if (fib6_rt_nh->rt == rt)
487 			return fib6_rt_nh;
488 	}
489 
490 	return NULL;
491 }
492 
493 static int nsim_fib6_rt_nh_add(struct nsim_fib6_rt *fib6_rt,
494 			       struct fib6_info *rt)
495 {
496 	struct nsim_fib6_rt_nh *fib6_rt_nh;
497 
498 	fib6_rt_nh = kzalloc(sizeof(*fib6_rt_nh), GFP_KERNEL);
499 	if (!fib6_rt_nh)
500 		return -ENOMEM;
501 
502 	fib6_info_hold(rt);
503 	fib6_rt_nh->rt = rt;
504 	list_add_tail(&fib6_rt_nh->list, &fib6_rt->nh_list);
505 	fib6_rt->nhs++;
506 
507 	return 0;
508 }
509 
510 #if IS_ENABLED(CONFIG_IPV6)
511 static void nsim_rt6_release(struct fib6_info *rt)
512 {
513 	fib6_info_release(rt);
514 }
515 #else
516 static void nsim_rt6_release(struct fib6_info *rt)
517 {
518 }
519 #endif
520 
521 static void nsim_fib6_rt_nh_del(struct nsim_fib6_rt *fib6_rt,
522 				const struct fib6_info *rt)
523 {
524 	struct nsim_fib6_rt_nh *fib6_rt_nh;
525 
526 	fib6_rt_nh = nsim_fib6_rt_nh_find(fib6_rt, rt);
527 	if (!fib6_rt_nh)
528 		return;
529 
530 	fib6_rt->nhs--;
531 	list_del(&fib6_rt_nh->list);
532 	nsim_rt6_release(fib6_rt_nh->rt);
533 	kfree(fib6_rt_nh);
534 }
535 
536 static struct nsim_fib6_rt *
537 nsim_fib6_rt_create(struct nsim_fib_data *data,
538 		    struct fib6_info **rt_arr, unsigned int nrt6)
539 {
540 	struct fib6_info *rt = rt_arr[0];
541 	struct nsim_fib6_rt *fib6_rt;
542 	int i = 0;
543 	int err;
544 
545 	fib6_rt = kzalloc(sizeof(*fib6_rt), GFP_KERNEL);
546 	if (!fib6_rt)
547 		return ERR_PTR(-ENOMEM);
548 
549 	nsim_fib_rt_init(data, &fib6_rt->common, &rt->fib6_dst.addr,
550 			 sizeof(rt->fib6_dst.addr), rt->fib6_dst.plen, AF_INET6,
551 			 rt->fib6_table->tb6_id);
552 
553 	/* We consider a multipath IPv6 route as one entry, but it can be made
554 	 * up from several fib6_info structs (one for each nexthop), so we
555 	 * add them all to the same list under the entry.
556 	 */
557 	INIT_LIST_HEAD(&fib6_rt->nh_list);
558 
559 	for (i = 0; i < nrt6; i++) {
560 		err = nsim_fib6_rt_nh_add(fib6_rt, rt_arr[i]);
561 		if (err)
562 			goto err_fib6_rt_nh_del;
563 	}
564 
565 	return fib6_rt;
566 
567 err_fib6_rt_nh_del:
568 	for (i--; i >= 0; i--) {
569 		nsim_fib6_rt_nh_del(fib6_rt, rt_arr[i]);
570 	}
571 	nsim_fib_rt_fini(&fib6_rt->common);
572 	kfree(fib6_rt);
573 	return ERR_PTR(err);
574 }
575 
576 static void nsim_fib6_rt_destroy(struct nsim_fib6_rt *fib6_rt)
577 {
578 	struct nsim_fib6_rt_nh *iter, *tmp;
579 
580 	list_for_each_entry_safe(iter, tmp, &fib6_rt->nh_list, list)
581 		nsim_fib6_rt_nh_del(fib6_rt, iter->rt);
582 	WARN_ON_ONCE(!list_empty(&fib6_rt->nh_list));
583 	nsim_fib_rt_fini(&fib6_rt->common);
584 	kfree(fib6_rt);
585 }
586 
587 static struct nsim_fib6_rt *
588 nsim_fib6_rt_lookup(struct rhashtable *fib_rt_ht, const struct fib6_info *rt)
589 {
590 	struct nsim_fib_rt *fib_rt;
591 
592 	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &rt->fib6_dst.addr,
593 				    sizeof(rt->fib6_dst.addr),
594 				    rt->fib6_dst.plen, AF_INET6,
595 				    rt->fib6_table->tb6_id);
596 	if (!fib_rt)
597 		return NULL;
598 
599 	return container_of(fib_rt, struct nsim_fib6_rt, common);
600 }
601 
602 static int nsim_fib6_rt_append(struct nsim_fib_data *data,
603 			       struct nsim_fib6_event *fib6_event)
604 {
605 	struct fib6_info *rt = fib6_event->rt_arr[0];
606 	struct nsim_fib6_rt *fib6_rt;
607 	int i, err;
608 
609 	if (data->fail_route_offload) {
610 		/* For testing purposes, user set debugfs fail_route_offload
611 		 * value to true. Simulate hardware programming latency and then
612 		 * fail.
613 		 */
614 		msleep(1);
615 		return -EINVAL;
616 	}
617 
618 	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
619 	if (!fib6_rt)
620 		return -EINVAL;
621 
622 	for (i = 0; i < fib6_event->nrt6; i++) {
623 		err = nsim_fib6_rt_nh_add(fib6_rt, fib6_event->rt_arr[i]);
624 		if (err)
625 			goto err_fib6_rt_nh_del;
626 
627 		WRITE_ONCE(fib6_event->rt_arr[i]->trap, true);
628 	}
629 
630 	return 0;
631 
632 err_fib6_rt_nh_del:
633 	for (i--; i >= 0; i--) {
634 		WRITE_ONCE(fib6_event->rt_arr[i]->trap, false);
635 		nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
636 	}
637 	return err;
638 }
639 
640 #if IS_ENABLED(CONFIG_IPV6)
641 static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
642 						 struct fib6_info **rt_arr,
643 						 unsigned int nrt6)
644 
645 {
646 	struct net *net = devlink_net(data->devlink);
647 	int i;
648 
649 	for (i = 0; i < nrt6; i++)
650 		fib6_info_hw_flags_set(net, rt_arr[i], false, false, true);
651 }
652 #else
653 static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
654 						 struct fib6_info **rt_arr,
655 						 unsigned int nrt6)
656 {
657 }
658 #endif
659 
660 #if IS_ENABLED(CONFIG_IPV6)
661 static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
662 				      const struct nsim_fib6_rt *fib6_rt,
663 				      bool trap)
664 {
665 	struct net *net = devlink_net(data->devlink);
666 	struct nsim_fib6_rt_nh *fib6_rt_nh;
667 
668 	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list)
669 		fib6_info_hw_flags_set(net, fib6_rt_nh->rt, false, trap, false);
670 }
671 #else
672 static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
673 				      const struct nsim_fib6_rt *fib6_rt,
674 				      bool trap)
675 {
676 }
677 #endif
678 
679 static int nsim_fib6_rt_add(struct nsim_fib_data *data,
680 			    struct nsim_fib6_rt *fib6_rt)
681 {
682 	int err;
683 
684 	err = rhashtable_insert_fast(&data->fib_rt_ht,
685 				     &fib6_rt->common.ht_node,
686 				     nsim_fib_rt_ht_params);
687 
688 	if (err)
689 		goto err_fib_dismiss;
690 
691 	msleep(1);
692 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
693 
694 	return 0;
695 
696 err_fib_dismiss:
697 	/* Drop the accounting that was increased from the notification
698 	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
699 	 */
700 	nsim_fib_account(&data->ipv6.fib, false);
701 	return err;
702 }
703 
704 static int nsim_fib6_rt_replace(struct nsim_fib_data *data,
705 				struct nsim_fib6_rt *fib6_rt,
706 				struct nsim_fib6_rt *fib6_rt_old)
707 {
708 	int err;
709 
710 	/* We are replacing a route, so need to remove the accounting which
711 	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
712 	 */
713 	err = nsim_fib_account(&data->ipv6.fib, false);
714 	if (err)
715 		return err;
716 
717 	err = rhashtable_replace_fast(&data->fib_rt_ht,
718 				      &fib6_rt_old->common.ht_node,
719 				      &fib6_rt->common.ht_node,
720 				      nsim_fib_rt_ht_params);
721 
722 	if (err)
723 		return err;
724 
725 	msleep(1);
726 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
727 
728 	nsim_fib6_rt_hw_flags_set(data, fib6_rt_old, false);
729 	nsim_fib6_rt_destroy(fib6_rt_old);
730 
731 	return 0;
732 }
733 
734 static int nsim_fib6_rt_insert(struct nsim_fib_data *data,
735 			       struct nsim_fib6_event *fib6_event)
736 {
737 	struct fib6_info *rt = fib6_event->rt_arr[0];
738 	struct nsim_fib6_rt *fib6_rt, *fib6_rt_old;
739 	int err;
740 
741 	if (data->fail_route_offload) {
742 		/* For testing purposes, user set debugfs fail_route_offload
743 		 * value to true. Simulate hardware programming latency and then
744 		 * fail.
745 		 */
746 		msleep(1);
747 		return -EINVAL;
748 	}
749 
750 	fib6_rt = nsim_fib6_rt_create(data, fib6_event->rt_arr,
751 				      fib6_event->nrt6);
752 	if (IS_ERR(fib6_rt))
753 		return PTR_ERR(fib6_rt);
754 
755 	fib6_rt_old = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
756 	if (!fib6_rt_old)
757 		err = nsim_fib6_rt_add(data, fib6_rt);
758 	else
759 		err = nsim_fib6_rt_replace(data, fib6_rt, fib6_rt_old);
760 
761 	if (err)
762 		nsim_fib6_rt_destroy(fib6_rt);
763 
764 	return err;
765 }
766 
767 static void nsim_fib6_rt_remove(struct nsim_fib_data *data,
768 				struct nsim_fib6_event *fib6_event)
769 {
770 	struct fib6_info *rt = fib6_event->rt_arr[0];
771 	struct nsim_fib6_rt *fib6_rt;
772 	int i;
773 
774 	/* Multipath routes are first added to the FIB trie and only then
775 	 * notified. If we vetoed the addition, we will get a delete
776 	 * notification for a route we do not have. Therefore, do not warn if
777 	 * route was not found.
778 	 */
779 	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
780 	if (!fib6_rt)
781 		return;
782 
783 	/* If not all the nexthops are deleted, then only reduce the nexthop
784 	 * group.
785 	 */
786 	if (fib6_event->nrt6 != fib6_rt->nhs) {
787 		for (i = 0; i < fib6_event->nrt6; i++)
788 			nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
789 		return;
790 	}
791 
792 	rhashtable_remove_fast(&data->fib_rt_ht, &fib6_rt->common.ht_node,
793 			       nsim_fib_rt_ht_params);
794 	nsim_fib6_rt_destroy(fib6_rt);
795 }
796 
797 static int nsim_fib6_event_init(struct nsim_fib6_event *fib6_event,
798 				struct fib6_entry_notifier_info *fen6_info)
799 {
800 	struct fib6_info *rt = fen6_info->rt;
801 	struct fib6_info **rt_arr;
802 	struct fib6_info *iter;
803 	unsigned int nrt6;
804 	int i = 0;
805 
806 	nrt6 = fen6_info->nsiblings + 1;
807 
808 	rt_arr = kcalloc(nrt6, sizeof(struct fib6_info *), GFP_ATOMIC);
809 	if (!rt_arr)
810 		return -ENOMEM;
811 
812 	fib6_event->rt_arr = rt_arr;
813 	fib6_event->nrt6 = nrt6;
814 
815 	rt_arr[0] = rt;
816 	fib6_info_hold(rt);
817 
818 	if (!fen6_info->nsiblings)
819 		return 0;
820 
821 	list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
822 		if (i == fen6_info->nsiblings)
823 			break;
824 
825 		rt_arr[i + 1] = iter;
826 		fib6_info_hold(iter);
827 		i++;
828 	}
829 	WARN_ON_ONCE(i != fen6_info->nsiblings);
830 
831 	return 0;
832 }
833 
834 static void nsim_fib6_event_fini(struct nsim_fib6_event *fib6_event)
835 {
836 	int i;
837 
838 	for (i = 0; i < fib6_event->nrt6; i++)
839 		nsim_rt6_release(fib6_event->rt_arr[i]);
840 	kfree(fib6_event->rt_arr);
841 }
842 
843 static int nsim_fib6_event(struct nsim_fib_data *data,
844 			   struct nsim_fib6_event *fib6_event,
845 			   unsigned long event)
846 {
847 	int err;
848 
849 	if (fib6_event->rt_arr[0]->fib6_src.plen)
850 		return 0;
851 
852 	switch (event) {
853 	case FIB_EVENT_ENTRY_REPLACE:
854 		err = nsim_fib6_rt_insert(data, fib6_event);
855 		if (err)
856 			goto err_rt_offload_failed_flag_set;
857 		break;
858 	case FIB_EVENT_ENTRY_APPEND:
859 		err = nsim_fib6_rt_append(data, fib6_event);
860 		if (err)
861 			goto err_rt_offload_failed_flag_set;
862 		break;
863 	case FIB_EVENT_ENTRY_DEL:
864 		nsim_fib6_rt_remove(data, fib6_event);
865 		break;
866 	default:
867 		break;
868 	}
869 
870 	return 0;
871 
872 err_rt_offload_failed_flag_set:
873 	nsim_fib6_rt_offload_failed_flag_set(data, fib6_event->rt_arr,
874 					     fib6_event->nrt6);
875 	return err;
876 }
877 
878 static void nsim_fib_event(struct nsim_fib_event *fib_event)
879 {
880 	switch (fib_event->family) {
881 	case AF_INET:
882 		nsim_fib4_event(fib_event->data, &fib_event->fen_info,
883 				fib_event->event);
884 		fib_info_put(fib_event->fen_info.fi);
885 		break;
886 	case AF_INET6:
887 		nsim_fib6_event(fib_event->data, &fib_event->fib6_event,
888 				fib_event->event);
889 		nsim_fib6_event_fini(&fib_event->fib6_event);
890 		break;
891 	}
892 }
893 
894 static int nsim_fib4_prepare_event(struct fib_notifier_info *info,
895 				   struct nsim_fib_event *fib_event,
896 				   unsigned long event)
897 {
898 	struct nsim_fib_data *data = fib_event->data;
899 	struct fib_entry_notifier_info *fen_info;
900 	struct netlink_ext_ack *extack;
901 	int err = 0;
902 
903 	fen_info = container_of(info, struct fib_entry_notifier_info,
904 				info);
905 	fib_event->fen_info = *fen_info;
906 	extack = info->extack;
907 
908 	switch (event) {
909 	case FIB_EVENT_ENTRY_REPLACE:
910 		err = nsim_fib_account(&data->ipv4.fib, true);
911 		if (err) {
912 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
913 			return err;
914 		}
915 		break;
916 	case FIB_EVENT_ENTRY_DEL:
917 		nsim_fib_account(&data->ipv4.fib, false);
918 		break;
919 	}
920 
921 	/* Take reference on fib_info to prevent it from being
922 	 * freed while event is queued. Release it afterwards.
923 	 */
924 	fib_info_hold(fib_event->fen_info.fi);
925 
926 	return 0;
927 }
928 
929 static int nsim_fib6_prepare_event(struct fib_notifier_info *info,
930 				   struct nsim_fib_event *fib_event,
931 				   unsigned long event)
932 {
933 	struct nsim_fib_data *data = fib_event->data;
934 	struct fib6_entry_notifier_info *fen6_info;
935 	struct netlink_ext_ack *extack;
936 	int err = 0;
937 
938 	fen6_info = container_of(info, struct fib6_entry_notifier_info,
939 				 info);
940 
941 	err = nsim_fib6_event_init(&fib_event->fib6_event, fen6_info);
942 	if (err)
943 		return err;
944 
945 	extack = info->extack;
946 	switch (event) {
947 	case FIB_EVENT_ENTRY_REPLACE:
948 		err = nsim_fib_account(&data->ipv6.fib, true);
949 		if (err) {
950 			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
951 			goto err_fib6_event_fini;
952 		}
953 		break;
954 	case FIB_EVENT_ENTRY_DEL:
955 		nsim_fib_account(&data->ipv6.fib, false);
956 		break;
957 	}
958 
959 	return 0;
960 
961 err_fib6_event_fini:
962 	nsim_fib6_event_fini(&fib_event->fib6_event);
963 	return err;
964 }
965 
966 static int nsim_fib_event_schedule_work(struct nsim_fib_data *data,
967 					struct fib_notifier_info *info,
968 					unsigned long event)
969 {
970 	struct nsim_fib_event *fib_event;
971 	int err;
972 
973 	if (info->family != AF_INET && info->family != AF_INET6)
974 		/* netdevsim does not support 'RTNL_FAMILY_IP6MR' and
975 		 * 'RTNL_FAMILY_IPMR' and should ignore them.
976 		 */
977 		return NOTIFY_DONE;
978 
979 	fib_event = kzalloc(sizeof(*fib_event), GFP_ATOMIC);
980 	if (!fib_event)
981 		return NOTIFY_BAD;
982 
983 	fib_event->data = data;
984 	fib_event->event = event;
985 	fib_event->family = info->family;
986 
987 	switch (info->family) {
988 	case AF_INET:
989 		err = nsim_fib4_prepare_event(info, fib_event, event);
990 		break;
991 	case AF_INET6:
992 		err = nsim_fib6_prepare_event(info, fib_event, event);
993 		break;
994 	}
995 
996 	if (err)
997 		goto err_fib_prepare_event;
998 
999 	/* Enqueue the event and trigger the work */
1000 	spin_lock_bh(&data->fib_event_queue_lock);
1001 	list_add_tail(&fib_event->list, &data->fib_event_queue);
1002 	spin_unlock_bh(&data->fib_event_queue_lock);
1003 	schedule_work(&data->fib_event_work);
1004 
1005 	return NOTIFY_DONE;
1006 
1007 err_fib_prepare_event:
1008 	kfree(fib_event);
1009 	return NOTIFY_BAD;
1010 }
1011 
1012 static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
1013 			     void *ptr)
1014 {
1015 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1016 						  fib_nb);
1017 	struct fib_notifier_info *info = ptr;
1018 	int err;
1019 
1020 	switch (event) {
1021 	case FIB_EVENT_RULE_ADD:
1022 	case FIB_EVENT_RULE_DEL:
1023 		err = nsim_fib_rule_event(data, info,
1024 					  event == FIB_EVENT_RULE_ADD);
1025 		return notifier_from_errno(err);
1026 	case FIB_EVENT_ENTRY_REPLACE:
1027 	case FIB_EVENT_ENTRY_APPEND:
1028 	case FIB_EVENT_ENTRY_DEL:
1029 		return nsim_fib_event_schedule_work(data, info, event);
1030 	}
1031 
1032 	return NOTIFY_DONE;
1033 }
1034 
1035 static void nsim_fib4_rt_free(struct nsim_fib_rt *fib_rt,
1036 			      struct nsim_fib_data *data)
1037 {
1038 	struct devlink *devlink = data->devlink;
1039 	struct nsim_fib4_rt *fib4_rt;
1040 
1041 	fib4_rt = container_of(fib_rt, struct nsim_fib4_rt, common);
1042 	nsim_fib4_rt_hw_flags_set(devlink_net(devlink), fib4_rt, false);
1043 	nsim_fib_account(&data->ipv4.fib, false);
1044 	nsim_fib4_rt_destroy(fib4_rt);
1045 }
1046 
1047 static void nsim_fib6_rt_free(struct nsim_fib_rt *fib_rt,
1048 			      struct nsim_fib_data *data)
1049 {
1050 	struct nsim_fib6_rt *fib6_rt;
1051 
1052 	fib6_rt = container_of(fib_rt, struct nsim_fib6_rt, common);
1053 	nsim_fib6_rt_hw_flags_set(data, fib6_rt, false);
1054 	nsim_fib_account(&data->ipv6.fib, false);
1055 	nsim_fib6_rt_destroy(fib6_rt);
1056 }
1057 
1058 static void nsim_fib_rt_free(void *ptr, void *arg)
1059 {
1060 	struct nsim_fib_rt *fib_rt = ptr;
1061 	struct nsim_fib_data *data = arg;
1062 
1063 	switch (fib_rt->key.family) {
1064 	case AF_INET:
1065 		nsim_fib4_rt_free(fib_rt, data);
1066 		break;
1067 	case AF_INET6:
1068 		nsim_fib6_rt_free(fib_rt, data);
1069 		break;
1070 	default:
1071 		WARN_ON_ONCE(1);
1072 	}
1073 }
1074 
1075 /* inconsistent dump, trying again */
1076 static void nsim_fib_dump_inconsistent(struct notifier_block *nb)
1077 {
1078 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1079 						  fib_nb);
1080 	struct nsim_fib_rt *fib_rt, *fib_rt_tmp;
1081 
1082 	/* Flush the work to make sure there is no race with notifications. */
1083 	flush_work(&data->fib_event_work);
1084 
1085 	/* The notifier block is still not registered, so we do not need to
1086 	 * take any locks here.
1087 	 */
1088 	list_for_each_entry_safe(fib_rt, fib_rt_tmp, &data->fib_rt_list, list) {
1089 		rhashtable_remove_fast(&data->fib_rt_ht, &fib_rt->ht_node,
1090 				       nsim_fib_rt_ht_params);
1091 		nsim_fib_rt_free(fib_rt, data);
1092 	}
1093 
1094 	atomic64_set(&data->ipv4.rules.num, 0ULL);
1095 	atomic64_set(&data->ipv6.rules.num, 0ULL);
1096 }
1097 
1098 static struct nsim_nexthop *nsim_nexthop_create(struct nsim_fib_data *data,
1099 						struct nh_notifier_info *info)
1100 {
1101 	struct nsim_nexthop *nexthop;
1102 	u64 occ = 0;
1103 	int i;
1104 
1105 	nexthop = kzalloc(sizeof(*nexthop), GFP_KERNEL);
1106 	if (!nexthop)
1107 		return ERR_PTR(-ENOMEM);
1108 
1109 	nexthop->id = info->id;
1110 
1111 	/* Determine the number of nexthop entries the new nexthop will
1112 	 * occupy.
1113 	 */
1114 
1115 	switch (info->type) {
1116 	case NH_NOTIFIER_INFO_TYPE_SINGLE:
1117 		occ = 1;
1118 		break;
1119 	case NH_NOTIFIER_INFO_TYPE_GRP:
1120 		for (i = 0; i < info->nh_grp->num_nh; i++)
1121 			occ += info->nh_grp->nh_entries[i].weight;
1122 		break;
1123 	case NH_NOTIFIER_INFO_TYPE_RES_TABLE:
1124 		occ = info->nh_res_table->num_nh_buckets;
1125 		nexthop->is_resilient = true;
1126 		break;
1127 	default:
1128 		NL_SET_ERR_MSG_MOD(info->extack, "Unsupported nexthop type");
1129 		kfree(nexthop);
1130 		return ERR_PTR(-EOPNOTSUPP);
1131 	}
1132 
1133 	nexthop->occ = occ;
1134 	return nexthop;
1135 }
1136 
1137 static void nsim_nexthop_destroy(struct nsim_nexthop *nexthop)
1138 {
1139 	kfree(nexthop);
1140 }
1141 
1142 static int nsim_nexthop_account(struct nsim_fib_data *data, u64 occ,
1143 				bool add, struct netlink_ext_ack *extack)
1144 {
1145 	int i, err = 0;
1146 
1147 	if (add) {
1148 		for (i = 0; i < occ; i++)
1149 			if (!atomic64_add_unless(&data->nexthops.num, 1,
1150 						 data->nexthops.max)) {
1151 				err = -ENOSPC;
1152 				NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported nexthops");
1153 				goto err_num_decrease;
1154 			}
1155 	} else {
1156 		if (WARN_ON(occ > atomic64_read(&data->nexthops.num)))
1157 			return -EINVAL;
1158 		atomic64_sub(occ, &data->nexthops.num);
1159 	}
1160 
1161 	return err;
1162 
1163 err_num_decrease:
1164 	atomic64_sub(i, &data->nexthops.num);
1165 	return err;
1166 
1167 }
1168 
1169 static void nsim_nexthop_hw_flags_set(struct net *net,
1170 				      const struct nsim_nexthop *nexthop,
1171 				      bool trap)
1172 {
1173 	int i;
1174 
1175 	nexthop_set_hw_flags(net, nexthop->id, false, trap);
1176 
1177 	if (!nexthop->is_resilient)
1178 		return;
1179 
1180 	for (i = 0; i < nexthop->occ; i++)
1181 		nexthop_bucket_set_hw_flags(net, nexthop->id, i, false, trap);
1182 }
1183 
1184 static int nsim_nexthop_add(struct nsim_fib_data *data,
1185 			    struct nsim_nexthop *nexthop,
1186 			    struct netlink_ext_ack *extack)
1187 {
1188 	struct net *net = devlink_net(data->devlink);
1189 	int err;
1190 
1191 	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
1192 	if (err)
1193 		return err;
1194 
1195 	err = rhashtable_insert_fast(&data->nexthop_ht, &nexthop->ht_node,
1196 				     nsim_nexthop_ht_params);
1197 	if (err) {
1198 		NL_SET_ERR_MSG_MOD(extack, "Failed to insert nexthop");
1199 		goto err_nexthop_dismiss;
1200 	}
1201 
1202 	nsim_nexthop_hw_flags_set(net, nexthop, true);
1203 
1204 	return 0;
1205 
1206 err_nexthop_dismiss:
1207 	nsim_nexthop_account(data, nexthop->occ, false, extack);
1208 	return err;
1209 }
1210 
1211 static int nsim_nexthop_replace(struct nsim_fib_data *data,
1212 				struct nsim_nexthop *nexthop,
1213 				struct nsim_nexthop *nexthop_old,
1214 				struct netlink_ext_ack *extack)
1215 {
1216 	struct net *net = devlink_net(data->devlink);
1217 	int err;
1218 
1219 	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
1220 	if (err)
1221 		return err;
1222 
1223 	err = rhashtable_replace_fast(&data->nexthop_ht,
1224 				      &nexthop_old->ht_node, &nexthop->ht_node,
1225 				      nsim_nexthop_ht_params);
1226 	if (err) {
1227 		NL_SET_ERR_MSG_MOD(extack, "Failed to replace nexthop");
1228 		goto err_nexthop_dismiss;
1229 	}
1230 
1231 	nsim_nexthop_hw_flags_set(net, nexthop, true);
1232 	nsim_nexthop_account(data, nexthop_old->occ, false, extack);
1233 	nsim_nexthop_destroy(nexthop_old);
1234 
1235 	return 0;
1236 
1237 err_nexthop_dismiss:
1238 	nsim_nexthop_account(data, nexthop->occ, false, extack);
1239 	return err;
1240 }
1241 
1242 static int nsim_nexthop_insert(struct nsim_fib_data *data,
1243 			       struct nh_notifier_info *info)
1244 {
1245 	struct nsim_nexthop *nexthop, *nexthop_old;
1246 	int err;
1247 
1248 	nexthop = nsim_nexthop_create(data, info);
1249 	if (IS_ERR(nexthop))
1250 		return PTR_ERR(nexthop);
1251 
1252 	nexthop_old = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
1253 					     nsim_nexthop_ht_params);
1254 	if (!nexthop_old)
1255 		err = nsim_nexthop_add(data, nexthop, info->extack);
1256 	else
1257 		err = nsim_nexthop_replace(data, nexthop, nexthop_old,
1258 					   info->extack);
1259 
1260 	if (err)
1261 		nsim_nexthop_destroy(nexthop);
1262 
1263 	return err;
1264 }
1265 
1266 static void nsim_nexthop_remove(struct nsim_fib_data *data,
1267 				struct nh_notifier_info *info)
1268 {
1269 	struct nsim_nexthop *nexthop;
1270 
1271 	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
1272 					 nsim_nexthop_ht_params);
1273 	if (!nexthop)
1274 		return;
1275 
1276 	rhashtable_remove_fast(&data->nexthop_ht, &nexthop->ht_node,
1277 			       nsim_nexthop_ht_params);
1278 	nsim_nexthop_account(data, nexthop->occ, false, info->extack);
1279 	nsim_nexthop_destroy(nexthop);
1280 }
1281 
1282 static int nsim_nexthop_res_table_pre_replace(struct nsim_fib_data *data,
1283 					      struct nh_notifier_info *info)
1284 {
1285 	if (data->fail_res_nexthop_group_replace) {
1286 		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace a resilient nexthop group");
1287 		return -EINVAL;
1288 	}
1289 
1290 	return 0;
1291 }
1292 
1293 static int nsim_nexthop_bucket_replace(struct nsim_fib_data *data,
1294 				       struct nh_notifier_info *info)
1295 {
1296 	if (data->fail_nexthop_bucket_replace) {
1297 		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace nexthop bucket");
1298 		return -EINVAL;
1299 	}
1300 
1301 	nexthop_bucket_set_hw_flags(info->net, info->id,
1302 				    info->nh_res_bucket->bucket_index,
1303 				    false, true);
1304 
1305 	return 0;
1306 }
1307 
1308 static int nsim_nexthop_event_nb(struct notifier_block *nb, unsigned long event,
1309 				 void *ptr)
1310 {
1311 	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
1312 						  nexthop_nb);
1313 	struct nh_notifier_info *info = ptr;
1314 	int err = 0;
1315 
1316 	mutex_lock(&data->nh_lock);
1317 	switch (event) {
1318 	case NEXTHOP_EVENT_REPLACE:
1319 		err = nsim_nexthop_insert(data, info);
1320 		break;
1321 	case NEXTHOP_EVENT_DEL:
1322 		nsim_nexthop_remove(data, info);
1323 		break;
1324 	case NEXTHOP_EVENT_RES_TABLE_PRE_REPLACE:
1325 		err = nsim_nexthop_res_table_pre_replace(data, info);
1326 		break;
1327 	case NEXTHOP_EVENT_BUCKET_REPLACE:
1328 		err = nsim_nexthop_bucket_replace(data, info);
1329 		break;
1330 	default:
1331 		break;
1332 	}
1333 
1334 	mutex_unlock(&data->nh_lock);
1335 	return notifier_from_errno(err);
1336 }
1337 
1338 static void nsim_nexthop_free(void *ptr, void *arg)
1339 {
1340 	struct nsim_nexthop *nexthop = ptr;
1341 	struct nsim_fib_data *data = arg;
1342 	struct net *net;
1343 
1344 	net = devlink_net(data->devlink);
1345 	nsim_nexthop_hw_flags_set(net, nexthop, false);
1346 	nsim_nexthop_account(data, nexthop->occ, false, NULL);
1347 	nsim_nexthop_destroy(nexthop);
1348 }
1349 
1350 static ssize_t nsim_nexthop_bucket_activity_write(struct file *file,
1351 						  const char __user *user_buf,
1352 						  size_t size, loff_t *ppos)
1353 {
1354 	struct nsim_fib_data *data = file->private_data;
1355 	struct net *net = devlink_net(data->devlink);
1356 	struct nsim_nexthop *nexthop;
1357 	unsigned long *activity;
1358 	loff_t pos = *ppos;
1359 	u16 bucket_index;
1360 	char buf[128];
1361 	int err = 0;
1362 	u32 nhid;
1363 
1364 	if (pos != 0)
1365 		return -EINVAL;
1366 	if (size > sizeof(buf))
1367 		return -EINVAL;
1368 	if (copy_from_user(buf, user_buf, size))
1369 		return -EFAULT;
1370 	if (sscanf(buf, "%u %hu", &nhid, &bucket_index) != 2)
1371 		return -EINVAL;
1372 
1373 	rtnl_lock();
1374 
1375 	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &nhid,
1376 					 nsim_nexthop_ht_params);
1377 	if (!nexthop || !nexthop->is_resilient ||
1378 	    bucket_index >= nexthop->occ) {
1379 		err = -EINVAL;
1380 		goto out;
1381 	}
1382 
1383 	activity = bitmap_zalloc(nexthop->occ, GFP_KERNEL);
1384 	if (!activity) {
1385 		err = -ENOMEM;
1386 		goto out;
1387 	}
1388 
1389 	bitmap_set(activity, bucket_index, 1);
1390 	nexthop_res_grp_activity_update(net, nhid, nexthop->occ, activity);
1391 	bitmap_free(activity);
1392 
1393 out:
1394 	rtnl_unlock();
1395 
1396 	*ppos = size;
1397 	return err ?: size;
1398 }
1399 
1400 static const struct file_operations nsim_nexthop_bucket_activity_fops = {
1401 	.open = simple_open,
1402 	.write = nsim_nexthop_bucket_activity_write,
1403 	.llseek = no_llseek,
1404 	.owner = THIS_MODULE,
1405 };
1406 
1407 static u64 nsim_fib_ipv4_resource_occ_get(void *priv)
1408 {
1409 	struct nsim_fib_data *data = priv;
1410 
1411 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB, false);
1412 }
1413 
1414 static u64 nsim_fib_ipv4_rules_res_occ_get(void *priv)
1415 {
1416 	struct nsim_fib_data *data = priv;
1417 
1418 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB_RULES, false);
1419 }
1420 
1421 static u64 nsim_fib_ipv6_resource_occ_get(void *priv)
1422 {
1423 	struct nsim_fib_data *data = priv;
1424 
1425 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB, false);
1426 }
1427 
1428 static u64 nsim_fib_ipv6_rules_res_occ_get(void *priv)
1429 {
1430 	struct nsim_fib_data *data = priv;
1431 
1432 	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB_RULES, false);
1433 }
1434 
1435 static u64 nsim_fib_nexthops_res_occ_get(void *priv)
1436 {
1437 	struct nsim_fib_data *data = priv;
1438 
1439 	return nsim_fib_get_val(data, NSIM_RESOURCE_NEXTHOPS, false);
1440 }
1441 
1442 static void nsim_fib_set_max_all(struct nsim_fib_data *data,
1443 				 struct devlink *devlink)
1444 {
1445 	static const enum nsim_resource_id res_ids[] = {
1446 		NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES,
1447 		NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES,
1448 		NSIM_RESOURCE_NEXTHOPS,
1449 	};
1450 	int i;
1451 
1452 	for (i = 0; i < ARRAY_SIZE(res_ids); i++) {
1453 		int err;
1454 		u64 val;
1455 
1456 		err = devlink_resource_size_get(devlink, res_ids[i], &val);
1457 		if (err)
1458 			val = (u64) -1;
1459 		nsim_fib_set_max(data, res_ids[i], val);
1460 	}
1461 }
1462 
1463 static void nsim_fib_event_work(struct work_struct *work)
1464 {
1465 	struct nsim_fib_data *data = container_of(work, struct nsim_fib_data,
1466 						  fib_event_work);
1467 	struct nsim_fib_event *fib_event, *next_fib_event;
1468 
1469 	LIST_HEAD(fib_event_queue);
1470 
1471 	spin_lock_bh(&data->fib_event_queue_lock);
1472 	list_splice_init(&data->fib_event_queue, &fib_event_queue);
1473 	spin_unlock_bh(&data->fib_event_queue_lock);
1474 
1475 	mutex_lock(&data->fib_lock);
1476 	list_for_each_entry_safe(fib_event, next_fib_event, &fib_event_queue,
1477 				 list) {
1478 		nsim_fib_event(fib_event);
1479 		list_del(&fib_event->list);
1480 		kfree(fib_event);
1481 		cond_resched();
1482 	}
1483 	mutex_unlock(&data->fib_lock);
1484 }
1485 
1486 static int
1487 nsim_fib_debugfs_init(struct nsim_fib_data *data, struct nsim_dev *nsim_dev)
1488 {
1489 	data->ddir = debugfs_create_dir("fib", nsim_dev->ddir);
1490 	if (IS_ERR(data->ddir))
1491 		return PTR_ERR(data->ddir);
1492 
1493 	data->fail_route_offload = false;
1494 	debugfs_create_bool("fail_route_offload", 0600, data->ddir,
1495 			    &data->fail_route_offload);
1496 
1497 	data->fail_res_nexthop_group_replace = false;
1498 	debugfs_create_bool("fail_res_nexthop_group_replace", 0600, data->ddir,
1499 			    &data->fail_res_nexthop_group_replace);
1500 
1501 	data->fail_nexthop_bucket_replace = false;
1502 	debugfs_create_bool("fail_nexthop_bucket_replace", 0600, data->ddir,
1503 			    &data->fail_nexthop_bucket_replace);
1504 
1505 	debugfs_create_file("nexthop_bucket_activity", 0200, data->ddir,
1506 			    data, &nsim_nexthop_bucket_activity_fops);
1507 	return 0;
1508 }
1509 
1510 static void nsim_fib_debugfs_exit(struct nsim_fib_data *data)
1511 {
1512 	debugfs_remove_recursive(data->ddir);
1513 }
1514 
1515 struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
1516 				      struct netlink_ext_ack *extack)
1517 {
1518 	struct nsim_fib_data *data;
1519 	struct nsim_dev *nsim_dev;
1520 	int err;
1521 
1522 	data = kzalloc(sizeof(*data), GFP_KERNEL);
1523 	if (!data)
1524 		return ERR_PTR(-ENOMEM);
1525 	data->devlink = devlink;
1526 
1527 	nsim_dev = devlink_priv(devlink);
1528 	err = nsim_fib_debugfs_init(data, nsim_dev);
1529 	if (err)
1530 		goto err_data_free;
1531 
1532 	mutex_init(&data->nh_lock);
1533 	err = rhashtable_init(&data->nexthop_ht, &nsim_nexthop_ht_params);
1534 	if (err)
1535 		goto err_debugfs_exit;
1536 
1537 	mutex_init(&data->fib_lock);
1538 	INIT_LIST_HEAD(&data->fib_rt_list);
1539 	err = rhashtable_init(&data->fib_rt_ht, &nsim_fib_rt_ht_params);
1540 	if (err)
1541 		goto err_rhashtable_nexthop_destroy;
1542 
1543 	INIT_WORK(&data->fib_event_work, nsim_fib_event_work);
1544 	INIT_LIST_HEAD(&data->fib_event_queue);
1545 	spin_lock_init(&data->fib_event_queue_lock);
1546 
1547 	nsim_fib_set_max_all(data, devlink);
1548 
1549 	data->nexthop_nb.notifier_call = nsim_nexthop_event_nb;
1550 	err = register_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb,
1551 					extack);
1552 	if (err) {
1553 		pr_err("Failed to register nexthop notifier\n");
1554 		goto err_rhashtable_fib_destroy;
1555 	}
1556 
1557 	data->fib_nb.notifier_call = nsim_fib_event_nb;
1558 	err = register_fib_notifier(devlink_net(devlink), &data->fib_nb,
1559 				    nsim_fib_dump_inconsistent, extack);
1560 	if (err) {
1561 		pr_err("Failed to register fib notifier\n");
1562 		goto err_nexthop_nb_unregister;
1563 	}
1564 
1565 	devlink_resource_occ_get_register(devlink,
1566 					  NSIM_RESOURCE_IPV4_FIB,
1567 					  nsim_fib_ipv4_resource_occ_get,
1568 					  data);
1569 	devlink_resource_occ_get_register(devlink,
1570 					  NSIM_RESOURCE_IPV4_FIB_RULES,
1571 					  nsim_fib_ipv4_rules_res_occ_get,
1572 					  data);
1573 	devlink_resource_occ_get_register(devlink,
1574 					  NSIM_RESOURCE_IPV6_FIB,
1575 					  nsim_fib_ipv6_resource_occ_get,
1576 					  data);
1577 	devlink_resource_occ_get_register(devlink,
1578 					  NSIM_RESOURCE_IPV6_FIB_RULES,
1579 					  nsim_fib_ipv6_rules_res_occ_get,
1580 					  data);
1581 	devlink_resource_occ_get_register(devlink,
1582 					  NSIM_RESOURCE_NEXTHOPS,
1583 					  nsim_fib_nexthops_res_occ_get,
1584 					  data);
1585 	return data;
1586 
1587 err_nexthop_nb_unregister:
1588 	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
1589 err_rhashtable_fib_destroy:
1590 	flush_work(&data->fib_event_work);
1591 	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
1592 				    data);
1593 err_rhashtable_nexthop_destroy:
1594 	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
1595 				    data);
1596 	mutex_destroy(&data->fib_lock);
1597 err_debugfs_exit:
1598 	mutex_destroy(&data->nh_lock);
1599 	nsim_fib_debugfs_exit(data);
1600 err_data_free:
1601 	kfree(data);
1602 	return ERR_PTR(err);
1603 }
1604 
1605 void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *data)
1606 {
1607 	devlink_resource_occ_get_unregister(devlink,
1608 					    NSIM_RESOURCE_NEXTHOPS);
1609 	devlink_resource_occ_get_unregister(devlink,
1610 					    NSIM_RESOURCE_IPV6_FIB_RULES);
1611 	devlink_resource_occ_get_unregister(devlink,
1612 					    NSIM_RESOURCE_IPV6_FIB);
1613 	devlink_resource_occ_get_unregister(devlink,
1614 					    NSIM_RESOURCE_IPV4_FIB_RULES);
1615 	devlink_resource_occ_get_unregister(devlink,
1616 					    NSIM_RESOURCE_IPV4_FIB);
1617 	unregister_fib_notifier(devlink_net(devlink), &data->fib_nb);
1618 	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
1619 	flush_work(&data->fib_event_work);
1620 	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
1621 				    data);
1622 	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
1623 				    data);
1624 	WARN_ON_ONCE(!list_empty(&data->fib_event_queue));
1625 	WARN_ON_ONCE(!list_empty(&data->fib_rt_list));
1626 	mutex_destroy(&data->fib_lock);
1627 	mutex_destroy(&data->nh_lock);
1628 	nsim_fib_debugfs_exit(data);
1629 	kfree(data);
1630 }
1631