Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1669 insertions, 0 deletions

diff --git a/drivers/net/netdevsim/fib.c b/drivers/net/netdevsim/fib.c
new file mode 100644
index 000000000..a1f91ff8e
--- /dev/null
+++ b/drivers/net/netdevsim/fib.c
@@ -0,0 +1,1669 @@
+/*
+ * Copyright (c) 2018 Cumulus Networks. All rights reserved.
+ * Copyright (c) 2018 David Ahern <dsa@cumulusnetworks.com>
+ *
+ * This software is licensed under the GNU General License Version 2,
+ * June 1991 as shown in the file COPYING in the top-level directory of this
+ * source tree.
+ *
+ * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
+ * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
+ * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
+ * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+ */
+
+#include <linux/bitmap.h>
+#include <linux/in6.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/rhashtable.h>
+#include <linux/spinlock_types.h>
+#include <linux/types.h>
+#include <net/fib_notifier.h>
+#include <net/inet_dscp.h>
+#include <net/ip_fib.h>
+#include <net/ip6_fib.h>
+#include <net/fib_rules.h>
+#include <net/net_namespace.h>
+#include <net/nexthop.h>
+#include <linux/debugfs.h>
+
+#include "netdevsim.h"
+
+struct nsim_fib_entry {
+	u64 max;
+	atomic64_t num;
+};
+
+struct nsim_per_fib_data {
+	struct nsim_fib_entry fib;
+	struct nsim_fib_entry rules;
+};
+
+struct nsim_fib_data {
+	struct notifier_block fib_nb;
+	struct nsim_per_fib_data ipv4;
+	struct nsim_per_fib_data ipv6;
+	struct nsim_fib_entry nexthops;
+	struct rhashtable fib_rt_ht;
+	struct list_head fib_rt_list;
+	struct mutex fib_lock; /* Protects FIB HT and list */
+	struct notifier_block nexthop_nb;
+	struct rhashtable nexthop_ht;
+	struct devlink *devlink;
+	struct work_struct fib_event_work;
+	struct work_struct fib_flush_work;
+	struct list_head fib_event_queue;
+	spinlock_t fib_event_queue_lock; /* Protects fib event queue list */
+	struct mutex nh_lock; /* Protects NH HT */
+	struct dentry *ddir;
+	bool fail_route_offload;
+	bool fail_res_nexthop_group_replace;
+	bool fail_nexthop_bucket_replace;
+	bool fail_route_delete;
+};
+
+struct nsim_fib_rt_key {
+	unsigned char addr[sizeof(struct in6_addr)];
+	unsigned char prefix_len;
+	int family;
+	u32 tb_id;
+};
+
+struct nsim_fib_rt {
+	struct nsim_fib_rt_key key;
+	struct rhash_head ht_node;
+	struct list_head list;	/* Member of fib_rt_list */
+};
+
+struct nsim_fib4_rt {
+	struct nsim_fib_rt common;
+	struct fib_info *fi;
+	dscp_t dscp;
+	u8 type;
+};
+
+struct nsim_fib6_rt {
+	struct nsim_fib_rt common;
+	struct list_head nh_list;
+	unsigned int nhs;
+};
+
+struct nsim_fib6_rt_nh {
+	struct list_head list;	/* Member of nh_list */
+	struct fib6_info *rt;
+};
+
+struct nsim_fib6_event {
+	struct fib6_info **rt_arr;
+	unsigned int nrt6;
+};
+
+struct nsim_fib_event {
+	struct list_head list; /* node in fib queue */
+	union {
+		struct fib_entry_notifier_info fen_info;
+		struct nsim_fib6_event fib6_event;
+	};
+	struct nsim_fib_data *data;
+	unsigned long event;
+	int family;
+};
+
+static const struct rhashtable_params nsim_fib_rt_ht_params = {
+	.key_offset = offsetof(struct nsim_fib_rt, key),
+	.head_offset = offsetof(struct nsim_fib_rt, ht_node),
+	.key_len = sizeof(struct nsim_fib_rt_key),
+	.automatic_shrinking = true,
+};
+
+struct nsim_nexthop {
+	struct rhash_head ht_node;
+	u64 occ;
+	u32 id;
+	bool is_resilient;
+};
+
+static const struct rhashtable_params nsim_nexthop_ht_params = {
+	.key_offset = offsetof(struct nsim_nexthop, id),
+	.head_offset = offsetof(struct nsim_nexthop, ht_node),
+	.key_len = sizeof(u32),
+	.automatic_shrinking = true,
+};
+
+u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
+		     enum nsim_resource_id res_id, bool max)
+{
+	struct nsim_fib_entry *entry;
+
+	switch (res_id) {
+	case NSIM_RESOURCE_IPV4_FIB:
+		entry = &fib_data->ipv4.fib;
+		break;
+	case NSIM_RESOURCE_IPV4_FIB_RULES:
+		entry = &fib_data->ipv4.rules;
+		break;
+	case NSIM_RESOURCE_IPV6_FIB:
+		entry = &fib_data->ipv6.fib;
+		break;
+	case NSIM_RESOURCE_IPV6_FIB_RULES:
+		entry = &fib_data->ipv6.rules;
+		break;
+	case NSIM_RESOURCE_NEXTHOPS:
+		entry = &fib_data->nexthops;
+		break;
+	default:
+		return 0;
+	}
+
+	return max ? entry->max : atomic64_read(&entry->num);
+}
+
+static void nsim_fib_set_max(struct nsim_fib_data *fib_data,
+			     enum nsim_resource_id res_id, u64 val)
+{
+	struct nsim_fib_entry *entry;
+
+	switch (res_id) {
+	case NSIM_RESOURCE_IPV4_FIB:
+		entry = &fib_data->ipv4.fib;
+		break;
+	case NSIM_RESOURCE_IPV4_FIB_RULES:
+		entry = &fib_data->ipv4.rules;
+		break;
+	case NSIM_RESOURCE_IPV6_FIB:
+		entry = &fib_data->ipv6.fib;
+		break;
+	case NSIM_RESOURCE_IPV6_FIB_RULES:
+		entry = &fib_data->ipv6.rules;
+		break;
+	case NSIM_RESOURCE_NEXTHOPS:
+		entry = &fib_data->nexthops;
+		break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+	entry->max = val;
+}
+
+static int nsim_fib_rule_account(struct nsim_fib_entry *entry, bool add,
+				 struct netlink_ext_ack *extack)
+{
+	int err = 0;
+
+	if (add) {
+		if (!atomic64_add_unless(&entry->num, 1, entry->max)) {
+			err = -ENOSPC;
+			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib rule entries");
+		}
+	} else {
+		atomic64_dec_if_positive(&entry->num);
+	}
+
+	return err;
+}
+
+static int nsim_fib_rule_event(struct nsim_fib_data *data,
+			       struct fib_notifier_info *info, bool add)
+{
+	struct netlink_ext_ack *extack = info->extack;
+	int err = 0;
+
+	switch (info->family) {
+	case AF_INET:
+		err = nsim_fib_rule_account(&data->ipv4.rules, add, extack);
+		break;
+	case AF_INET6:
+		err = nsim_fib_rule_account(&data->ipv6.rules, add, extack);
+		break;
+	}
+
+	return err;
+}
+
+static int nsim_fib_account(struct nsim_fib_entry *entry, bool add)
+{
+	int err = 0;
+
+	if (add) {
+		if (!atomic64_add_unless(&entry->num, 1, entry->max))
+			err = -ENOSPC;
+	} else {
+		atomic64_dec_if_positive(&entry->num);
+	}
+
+	return err;
+}
+
+static void 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)
+{
+	memcpy(fib_rt->key.addr, addr, addr_len);
+	fib_rt->key.prefix_len = prefix_len;
+	fib_rt->key.family = family;
+	fib_rt->key.tb_id = tb_id;
+	list_add(&fib_rt->list, &data->fib_rt_list);
+}
+
+static void nsim_fib_rt_fini(struct nsim_fib_rt *fib_rt)
+{
+	list_del(&fib_rt->list);
+}
+
+static struct nsim_fib_rt *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)
+{
+	struct nsim_fib_rt_key key;
+
+	memset(&key, 0, sizeof(key));
+	memcpy(key.addr, addr, addr_len);
+	key.prefix_len = prefix_len;
+	key.family = family;
+	key.tb_id = tb_id;
+
+	return rhashtable_lookup_fast(fib_rt_ht, &key, nsim_fib_rt_ht_params);
+}
+
+static struct nsim_fib4_rt *
+nsim_fib4_rt_create(struct nsim_fib_data *data,
+		    struct fib_entry_notifier_info *fen_info)
+{
+	struct nsim_fib4_rt *fib4_rt;
+
+	fib4_rt = kzalloc(sizeof(*fib4_rt), GFP_KERNEL);
+	if (!fib4_rt)
+		return NULL;
+
+	nsim_fib_rt_init(data, &fib4_rt->common, &fen_info->dst, sizeof(u32),
+			 fen_info->dst_len, AF_INET, fen_info->tb_id);
+
+	fib4_rt->fi = fen_info->fi;
+	fib_info_hold(fib4_rt->fi);
+	fib4_rt->dscp = fen_info->dscp;
+	fib4_rt->type = fen_info->type;
+
+	return fib4_rt;
+}
+
+static void nsim_fib4_rt_destroy(struct nsim_fib4_rt *fib4_rt)
+{
+	fib_info_put(fib4_rt->fi);
+	nsim_fib_rt_fini(&fib4_rt->common);
+	kfree(fib4_rt);
+}
+
+static struct nsim_fib4_rt *
+nsim_fib4_rt_lookup(struct rhashtable *fib_rt_ht,
+		    const struct fib_entry_notifier_info *fen_info)
+{
+	struct nsim_fib_rt *fib_rt;
+
+	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &fen_info->dst, sizeof(u32),
+				    fen_info->dst_len, AF_INET,
+				    fen_info->tb_id);
+	if (!fib_rt)
+		return NULL;
+
+	return container_of(fib_rt, struct nsim_fib4_rt, common);
+}
+
+static void
+nsim_fib4_rt_offload_failed_flag_set(struct net *net,
+				     struct fib_entry_notifier_info *fen_info)
+{
+	u32 *p_dst = (u32 *)&fen_info->dst;
+	struct fib_rt_info fri;
+
+	fri.fi = fen_info->fi;
+	fri.tb_id = fen_info->tb_id;
+	fri.dst = cpu_to_be32(*p_dst);
+	fri.dst_len = fen_info->dst_len;
+	fri.dscp = fen_info->dscp;
+	fri.type = fen_info->type;
+	fri.offload = false;
+	fri.trap = false;
+	fri.offload_failed = true;
+	fib_alias_hw_flags_set(net, &fri);
+}
+
+static void nsim_fib4_rt_hw_flags_set(struct net *net,
+				      const struct nsim_fib4_rt *fib4_rt,
+				      bool trap)
+{
+	u32 *p_dst = (u32 *) fib4_rt->common.key.addr;
+	int dst_len = fib4_rt->common.key.prefix_len;
+	struct fib_rt_info fri;
+
+	fri.fi = fib4_rt->fi;
+	fri.tb_id = fib4_rt->common.key.tb_id;
+	fri.dst = cpu_to_be32(*p_dst);
+	fri.dst_len = dst_len;
+	fri.dscp = fib4_rt->dscp;
+	fri.type = fib4_rt->type;
+	fri.offload = false;
+	fri.trap = trap;
+	fri.offload_failed = false;
+	fib_alias_hw_flags_set(net, &fri);
+}
+
+static int nsim_fib4_rt_add(struct nsim_fib_data *data,
+			    struct nsim_fib4_rt *fib4_rt)
+{
+	struct net *net = devlink_net(data->devlink);
+	int err;
+
+	err = rhashtable_insert_fast(&data->fib_rt_ht,
+				     &fib4_rt->common.ht_node,
+				     nsim_fib_rt_ht_params);
+	if (err)
+		goto err_fib_dismiss;
+
+	/* Simulate hardware programming latency. */
+	msleep(1);
+	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
+
+	return 0;
+
+err_fib_dismiss:
+	/* Drop the accounting that was increased from the notification
+	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
+	 */
+	nsim_fib_account(&data->ipv4.fib, false);
+	return err;
+}
+
+static int nsim_fib4_rt_replace(struct nsim_fib_data *data,
+				struct nsim_fib4_rt *fib4_rt,
+				struct nsim_fib4_rt *fib4_rt_old)
+{
+	struct net *net = devlink_net(data->devlink);
+	int err;
+
+	/* We are replacing a route, so need to remove the accounting which
+	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
+	 */
+	err = nsim_fib_account(&data->ipv4.fib, false);
+	if (err)
+		return err;
+	err = rhashtable_replace_fast(&data->fib_rt_ht,
+				      &fib4_rt_old->common.ht_node,
+				      &fib4_rt->common.ht_node,
+				      nsim_fib_rt_ht_params);
+	if (err)
+		return err;
+
+	msleep(1);
+	nsim_fib4_rt_hw_flags_set(net, fib4_rt, true);
+
+	nsim_fib4_rt_hw_flags_set(net, fib4_rt_old, false);
+	nsim_fib4_rt_destroy(fib4_rt_old);
+
+	return 0;
+}
+
+static int nsim_fib4_rt_insert(struct nsim_fib_data *data,
+			       struct fib_entry_notifier_info *fen_info)
+{
+	struct nsim_fib4_rt *fib4_rt, *fib4_rt_old;
+	int err;
+
+	if (data->fail_route_offload) {
+		/* For testing purposes, user set debugfs fail_route_offload
+		 * value to true. Simulate hardware programming latency and then
+		 * fail.
+		 */
+		msleep(1);
+		return -EINVAL;
+	}
+
+	fib4_rt = nsim_fib4_rt_create(data, fen_info);
+	if (!fib4_rt)
+		return -ENOMEM;
+
+	fib4_rt_old = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
+	if (!fib4_rt_old)
+		err = nsim_fib4_rt_add(data, fib4_rt);
+	else
+		err = nsim_fib4_rt_replace(data, fib4_rt, fib4_rt_old);
+
+	if (err)
+		nsim_fib4_rt_destroy(fib4_rt);
+
+	return err;
+}
+
+static void nsim_fib4_rt_remove(struct nsim_fib_data *data,
+				const struct fib_entry_notifier_info *fen_info)
+{
+	struct nsim_fib4_rt *fib4_rt;
+
+	fib4_rt = nsim_fib4_rt_lookup(&data->fib_rt_ht, fen_info);
+	if (!fib4_rt)
+		return;
+
+	rhashtable_remove_fast(&data->fib_rt_ht, &fib4_rt->common.ht_node,
+			       nsim_fib_rt_ht_params);
+	nsim_fib4_rt_destroy(fib4_rt);
+}
+
+static int nsim_fib4_event(struct nsim_fib_data *data,
+			   struct fib_entry_notifier_info *fen_info,
+			   unsigned long event)
+{
+	int err = 0;
+
+	switch (event) {
+	case FIB_EVENT_ENTRY_REPLACE:
+		err = nsim_fib4_rt_insert(data, fen_info);
+		if (err) {
+			struct net *net = devlink_net(data->devlink);
+
+			nsim_fib4_rt_offload_failed_flag_set(net, fen_info);
+		}
+		break;
+	case FIB_EVENT_ENTRY_DEL:
+		nsim_fib4_rt_remove(data, fen_info);
+		break;
+	default:
+		break;
+	}
+
+	return err;
+}
+
+static struct nsim_fib6_rt_nh *
+nsim_fib6_rt_nh_find(const struct nsim_fib6_rt *fib6_rt,
+		     const struct fib6_info *rt)
+{
+	struct nsim_fib6_rt_nh *fib6_rt_nh;
+
+	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list) {
+		if (fib6_rt_nh->rt == rt)
+			return fib6_rt_nh;
+	}
+
+	return NULL;
+}
+
+static int nsim_fib6_rt_nh_add(struct nsim_fib6_rt *fib6_rt,
+			       struct fib6_info *rt)
+{
+	struct nsim_fib6_rt_nh *fib6_rt_nh;
+
+	fib6_rt_nh = kzalloc(sizeof(*fib6_rt_nh), GFP_KERNEL);
+	if (!fib6_rt_nh)
+		return -ENOMEM;
+
+	fib6_info_hold(rt);
+	fib6_rt_nh->rt = rt;
+	list_add_tail(&fib6_rt_nh->list, &fib6_rt->nh_list);
+	fib6_rt->nhs++;
+
+	return 0;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void nsim_rt6_release(struct fib6_info *rt)
+{
+	fib6_info_release(rt);
+}
+#else
+static void nsim_rt6_release(struct fib6_info *rt)
+{
+}
+#endif
+
+static void nsim_fib6_rt_nh_del(struct nsim_fib6_rt *fib6_rt,
+				const struct fib6_info *rt)
+{
+	struct nsim_fib6_rt_nh *fib6_rt_nh;
+
+	fib6_rt_nh = nsim_fib6_rt_nh_find(fib6_rt, rt);
+	if (!fib6_rt_nh)
+		return;
+
+	fib6_rt->nhs--;
+	list_del(&fib6_rt_nh->list);
+	nsim_rt6_release(fib6_rt_nh->rt);
+	kfree(fib6_rt_nh);
+}
+
+static struct nsim_fib6_rt *
+nsim_fib6_rt_create(struct nsim_fib_data *data,
+		    struct fib6_info **rt_arr, unsigned int nrt6)
+{
+	struct fib6_info *rt = rt_arr[0];
+	struct nsim_fib6_rt *fib6_rt;
+	int i = 0;
+	int err;
+
+	fib6_rt = kzalloc(sizeof(*fib6_rt), GFP_KERNEL);
+	if (!fib6_rt)
+		return ERR_PTR(-ENOMEM);
+
+	nsim_fib_rt_init(data, &fib6_rt->common, &rt->fib6_dst.addr,
+			 sizeof(rt->fib6_dst.addr), rt->fib6_dst.plen, AF_INET6,
+			 rt->fib6_table->tb6_id);
+
+	/* We consider a multipath IPv6 route as one entry, but it can be made
+	 * up from several fib6_info structs (one for each nexthop), so we
+	 * add them all to the same list under the entry.
+	 */
+	INIT_LIST_HEAD(&fib6_rt->nh_list);
+
+	for (i = 0; i < nrt6; i++) {
+		err = nsim_fib6_rt_nh_add(fib6_rt, rt_arr[i]);
+		if (err)
+			goto err_fib6_rt_nh_del;
+	}
+
+	return fib6_rt;
+
+err_fib6_rt_nh_del:
+	for (i--; i >= 0; i--) {
+		nsim_fib6_rt_nh_del(fib6_rt, rt_arr[i]);
+	}
+	nsim_fib_rt_fini(&fib6_rt->common);
+	kfree(fib6_rt);
+	return ERR_PTR(err);
+}
+
+static void nsim_fib6_rt_destroy(struct nsim_fib6_rt *fib6_rt)
+{
+	struct nsim_fib6_rt_nh *iter, *tmp;
+
+	list_for_each_entry_safe(iter, tmp, &fib6_rt->nh_list, list)
+		nsim_fib6_rt_nh_del(fib6_rt, iter->rt);
+	WARN_ON_ONCE(!list_empty(&fib6_rt->nh_list));
+	nsim_fib_rt_fini(&fib6_rt->common);
+	kfree(fib6_rt);
+}
+
+static struct nsim_fib6_rt *
+nsim_fib6_rt_lookup(struct rhashtable *fib_rt_ht, const struct fib6_info *rt)
+{
+	struct nsim_fib_rt *fib_rt;
+
+	fib_rt = nsim_fib_rt_lookup(fib_rt_ht, &rt->fib6_dst.addr,
+				    sizeof(rt->fib6_dst.addr),
+				    rt->fib6_dst.plen, AF_INET6,
+				    rt->fib6_table->tb6_id);
+	if (!fib_rt)
+		return NULL;
+
+	return container_of(fib_rt, struct nsim_fib6_rt, common);
+}
+
+static int nsim_fib6_rt_append(struct nsim_fib_data *data,
+			       struct nsim_fib6_event *fib6_event)
+{
+	struct fib6_info *rt = fib6_event->rt_arr[0];
+	struct nsim_fib6_rt *fib6_rt;
+	int i, err;
+
+	if (data->fail_route_offload) {
+		/* For testing purposes, user set debugfs fail_route_offload
+		 * value to true. Simulate hardware programming latency and then
+		 * fail.
+		 */
+		msleep(1);
+		return -EINVAL;
+	}
+
+	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
+	if (!fib6_rt)
+		return -EINVAL;
+
+	for (i = 0; i < fib6_event->nrt6; i++) {
+		err = nsim_fib6_rt_nh_add(fib6_rt, fib6_event->rt_arr[i]);
+		if (err)
+			goto err_fib6_rt_nh_del;
+
+		WRITE_ONCE(fib6_event->rt_arr[i]->trap, true);
+	}
+
+	return 0;
+
+err_fib6_rt_nh_del:
+	for (i--; i >= 0; i--) {
+		WRITE_ONCE(fib6_event->rt_arr[i]->trap, false);
+		nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
+	}
+	return err;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
+						 struct fib6_info **rt_arr,
+						 unsigned int nrt6)
+
+{
+	struct net *net = devlink_net(data->devlink);
+	int i;
+
+	for (i = 0; i < nrt6; i++)
+		fib6_info_hw_flags_set(net, rt_arr[i], false, false, true);
+}
+#else
+static void nsim_fib6_rt_offload_failed_flag_set(struct nsim_fib_data *data,
+						 struct fib6_info **rt_arr,
+						 unsigned int nrt6)
+{
+}
+#endif
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
+				      const struct nsim_fib6_rt *fib6_rt,
+				      bool trap)
+{
+	struct net *net = devlink_net(data->devlink);
+	struct nsim_fib6_rt_nh *fib6_rt_nh;
+
+	list_for_each_entry(fib6_rt_nh, &fib6_rt->nh_list, list)
+		fib6_info_hw_flags_set(net, fib6_rt_nh->rt, false, trap, false);
+}
+#else
+static void nsim_fib6_rt_hw_flags_set(struct nsim_fib_data *data,
+				      const struct nsim_fib6_rt *fib6_rt,
+				      bool trap)
+{
+}
+#endif
+
+static int nsim_fib6_rt_add(struct nsim_fib_data *data,
+			    struct nsim_fib6_rt *fib6_rt)
+{
+	int err;
+
+	err = rhashtable_insert_fast(&data->fib_rt_ht,
+				     &fib6_rt->common.ht_node,
+				     nsim_fib_rt_ht_params);
+
+	if (err)
+		goto err_fib_dismiss;
+
+	msleep(1);
+	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
+
+	return 0;
+
+err_fib_dismiss:
+	/* Drop the accounting that was increased from the notification
+	 * context when FIB_EVENT_ENTRY_REPLACE was triggered.
+	 */
+	nsim_fib_account(&data->ipv6.fib, false);
+	return err;
+}
+
+static int nsim_fib6_rt_replace(struct nsim_fib_data *data,
+				struct nsim_fib6_rt *fib6_rt,
+				struct nsim_fib6_rt *fib6_rt_old)
+{
+	int err;
+
+	/* We are replacing a route, so need to remove the accounting which
+	 * was increased when FIB_EVENT_ENTRY_REPLACE was triggered.
+	 */
+	err = nsim_fib_account(&data->ipv6.fib, false);
+	if (err)
+		return err;
+
+	err = rhashtable_replace_fast(&data->fib_rt_ht,
+				      &fib6_rt_old->common.ht_node,
+				      &fib6_rt->common.ht_node,
+				      nsim_fib_rt_ht_params);
+
+	if (err)
+		return err;
+
+	msleep(1);
+	nsim_fib6_rt_hw_flags_set(data, fib6_rt, true);
+
+	nsim_fib6_rt_hw_flags_set(data, fib6_rt_old, false);
+	nsim_fib6_rt_destroy(fib6_rt_old);
+
+	return 0;
+}
+
+static int nsim_fib6_rt_insert(struct nsim_fib_data *data,
+			       struct nsim_fib6_event *fib6_event)
+{
+	struct fib6_info *rt = fib6_event->rt_arr[0];
+	struct nsim_fib6_rt *fib6_rt, *fib6_rt_old;
+	int err;
+
+	if (data->fail_route_offload) {
+		/* For testing purposes, user set debugfs fail_route_offload
+		 * value to true. Simulate hardware programming latency and then
+		 * fail.
+		 */
+		msleep(1);
+		return -EINVAL;
+	}
+
+	fib6_rt = nsim_fib6_rt_create(data, fib6_event->rt_arr,
+				      fib6_event->nrt6);
+	if (IS_ERR(fib6_rt))
+		return PTR_ERR(fib6_rt);
+
+	fib6_rt_old = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
+	if (!fib6_rt_old)
+		err = nsim_fib6_rt_add(data, fib6_rt);
+	else
+		err = nsim_fib6_rt_replace(data, fib6_rt, fib6_rt_old);
+
+	if (err)
+		nsim_fib6_rt_destroy(fib6_rt);
+
+	return err;
+}
+
+static void nsim_fib6_rt_remove(struct nsim_fib_data *data,
+				struct nsim_fib6_event *fib6_event)
+{
+	struct fib6_info *rt = fib6_event->rt_arr[0];
+	struct nsim_fib6_rt *fib6_rt;
+	int i;
+
+	/* Multipath routes are first added to the FIB trie and only then
+	 * notified. If we vetoed the addition, we will get a delete
+	 * notification for a route we do not have. Therefore, do not warn if
+	 * route was not found.
+	 */
+	fib6_rt = nsim_fib6_rt_lookup(&data->fib_rt_ht, rt);
+	if (!fib6_rt)
+		return;
+
+	/* If not all the nexthops are deleted, then only reduce the nexthop
+	 * group.
+	 */
+	if (fib6_event->nrt6 != fib6_rt->nhs) {
+		for (i = 0; i < fib6_event->nrt6; i++)
+			nsim_fib6_rt_nh_del(fib6_rt, fib6_event->rt_arr[i]);
+		return;
+	}
+
+	rhashtable_remove_fast(&data->fib_rt_ht, &fib6_rt->common.ht_node,
+			       nsim_fib_rt_ht_params);
+	nsim_fib6_rt_destroy(fib6_rt);
+}
+
+static int nsim_fib6_event_init(struct nsim_fib6_event *fib6_event,
+				struct fib6_entry_notifier_info *fen6_info)
+{
+	struct fib6_info *rt = fen6_info->rt;
+	struct fib6_info **rt_arr;
+	struct fib6_info *iter;
+	unsigned int nrt6;
+	int i = 0;
+
+	nrt6 = fen6_info->nsiblings + 1;
+
+	rt_arr = kcalloc(nrt6, sizeof(struct fib6_info *), GFP_ATOMIC);
+	if (!rt_arr)
+		return -ENOMEM;
+
+	fib6_event->rt_arr = rt_arr;
+	fib6_event->nrt6 = nrt6;
+
+	rt_arr[0] = rt;
+	fib6_info_hold(rt);
+
+	if (!fen6_info->nsiblings)
+		return 0;
+
+	list_for_each_entry(iter, &rt->fib6_siblings, fib6_siblings) {
+		if (i == fen6_info->nsiblings)
+			break;
+
+		rt_arr[i + 1] = iter;
+		fib6_info_hold(iter);
+		i++;
+	}
+	WARN_ON_ONCE(i != fen6_info->nsiblings);
+
+	return 0;
+}
+
+static void nsim_fib6_event_fini(struct nsim_fib6_event *fib6_event)
+{
+	int i;
+
+	for (i = 0; i < fib6_event->nrt6; i++)
+		nsim_rt6_release(fib6_event->rt_arr[i]);
+	kfree(fib6_event->rt_arr);
+}
+
+static int nsim_fib6_event(struct nsim_fib_data *data,
+			   struct nsim_fib6_event *fib6_event,
+			   unsigned long event)
+{
+	int err;
+
+	if (fib6_event->rt_arr[0]->fib6_src.plen)
+		return 0;
+
+	switch (event) {
+	case FIB_EVENT_ENTRY_REPLACE:
+		err = nsim_fib6_rt_insert(data, fib6_event);
+		if (err)
+			goto err_rt_offload_failed_flag_set;
+		break;
+	case FIB_EVENT_ENTRY_APPEND:
+		err = nsim_fib6_rt_append(data, fib6_event);
+		if (err)
+			goto err_rt_offload_failed_flag_set;
+		break;
+	case FIB_EVENT_ENTRY_DEL:
+		nsim_fib6_rt_remove(data, fib6_event);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+
+err_rt_offload_failed_flag_set:
+	nsim_fib6_rt_offload_failed_flag_set(data, fib6_event->rt_arr,
+					     fib6_event->nrt6);
+	return err;
+}
+
+static void nsim_fib_event(struct nsim_fib_event *fib_event)
+{
+	switch (fib_event->family) {
+	case AF_INET:
+		nsim_fib4_event(fib_event->data, &fib_event->fen_info,
+				fib_event->event);
+		fib_info_put(fib_event->fen_info.fi);
+		break;
+	case AF_INET6:
+		nsim_fib6_event(fib_event->data, &fib_event->fib6_event,
+				fib_event->event);
+		nsim_fib6_event_fini(&fib_event->fib6_event);
+		break;
+	}
+}
+
+static int nsim_fib4_prepare_event(struct fib_notifier_info *info,
+				   struct nsim_fib_event *fib_event,
+				   unsigned long event)
+{
+	struct nsim_fib_data *data = fib_event->data;
+	struct fib_entry_notifier_info *fen_info;
+	struct netlink_ext_ack *extack;
+	int err = 0;
+
+	fen_info = container_of(info, struct fib_entry_notifier_info,
+				info);
+	fib_event->fen_info = *fen_info;
+	extack = info->extack;
+
+	switch (event) {
+	case FIB_EVENT_ENTRY_REPLACE:
+		err = nsim_fib_account(&data->ipv4.fib, true);
+		if (err) {
+			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
+			return err;
+		}
+		break;
+	case FIB_EVENT_ENTRY_DEL:
+		if (data->fail_route_delete) {
+			NL_SET_ERR_MSG_MOD(extack, "Failed to process route deletion");
+			return -EINVAL;
+		}
+		nsim_fib_account(&data->ipv4.fib, false);
+		break;
+	}
+
+	/* Take reference on fib_info to prevent it from being
+	 * freed while event is queued. Release it afterwards.
+	 */
+	fib_info_hold(fib_event->fen_info.fi);
+
+	return 0;
+}
+
+static int nsim_fib6_prepare_event(struct fib_notifier_info *info,
+				   struct nsim_fib_event *fib_event,
+				   unsigned long event)
+{
+	struct nsim_fib_data *data = fib_event->data;
+	struct fib6_entry_notifier_info *fen6_info;
+	struct netlink_ext_ack *extack;
+	int err = 0;
+
+	fen6_info = container_of(info, struct fib6_entry_notifier_info,
+				 info);
+
+	err = nsim_fib6_event_init(&fib_event->fib6_event, fen6_info);
+	if (err)
+		return err;
+
+	extack = info->extack;
+	switch (event) {
+	case FIB_EVENT_ENTRY_REPLACE:
+		err = nsim_fib_account(&data->ipv6.fib, true);
+		if (err) {
+			NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported fib entries");
+			goto err_fib6_event_fini;
+		}
+		break;
+	case FIB_EVENT_ENTRY_DEL:
+		if (data->fail_route_delete) {
+			err = -EINVAL;
+			NL_SET_ERR_MSG_MOD(extack, "Failed to process route deletion");
+			goto err_fib6_event_fini;
+		}
+		nsim_fib_account(&data->ipv6.fib, false);
+		break;
+	}
+
+	return 0;
+
+err_fib6_event_fini:
+	nsim_fib6_event_fini(&fib_event->fib6_event);
+	return err;
+}
+
+static int nsim_fib_event_schedule_work(struct nsim_fib_data *data,
+					struct fib_notifier_info *info,
+					unsigned long event)
+{
+	struct nsim_fib_event *fib_event;
+	int err;
+
+	if (info->family != AF_INET && info->family != AF_INET6)
+		/* netdevsim does not support 'RTNL_FAMILY_IP6MR' and
+		 * 'RTNL_FAMILY_IPMR' and should ignore them.
+		 */
+		return NOTIFY_DONE;
+
+	fib_event = kzalloc(sizeof(*fib_event), GFP_ATOMIC);
+	if (!fib_event)
+		goto err_fib_event_alloc;
+
+	fib_event->data = data;
+	fib_event->event = event;
+	fib_event->family = info->family;
+
+	switch (info->family) {
+	case AF_INET:
+		err = nsim_fib4_prepare_event(info, fib_event, event);
+		break;
+	case AF_INET6:
+		err = nsim_fib6_prepare_event(info, fib_event, event);
+		break;
+	}
+
+	if (err)
+		goto err_fib_prepare_event;
+
+	/* Enqueue the event and trigger the work */
+	spin_lock_bh(&data->fib_event_queue_lock);
+	list_add_tail(&fib_event->list, &data->fib_event_queue);
+	spin_unlock_bh(&data->fib_event_queue_lock);
+	schedule_work(&data->fib_event_work);
+
+	return NOTIFY_DONE;
+
+err_fib_prepare_event:
+	kfree(fib_event);
+err_fib_event_alloc:
+	if (event == FIB_EVENT_ENTRY_DEL)
+		schedule_work(&data->fib_flush_work);
+	return NOTIFY_BAD;
+}
+
+static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
+			     void *ptr)
+{
+	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
+						  fib_nb);
+	struct fib_notifier_info *info = ptr;
+	int err;
+
+	switch (event) {
+	case FIB_EVENT_RULE_ADD:
+	case FIB_EVENT_RULE_DEL:
+		err = nsim_fib_rule_event(data, info,
+					  event == FIB_EVENT_RULE_ADD);
+		return notifier_from_errno(err);
+	case FIB_EVENT_ENTRY_REPLACE:
+	case FIB_EVENT_ENTRY_APPEND:
+	case FIB_EVENT_ENTRY_DEL:
+		return nsim_fib_event_schedule_work(data, info, event);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static void nsim_fib4_rt_free(struct nsim_fib_rt *fib_rt,
+			      struct nsim_fib_data *data)
+{
+	struct devlink *devlink = data->devlink;
+	struct nsim_fib4_rt *fib4_rt;
+
+	fib4_rt = container_of(fib_rt, struct nsim_fib4_rt, common);
+	nsim_fib4_rt_hw_flags_set(devlink_net(devlink), fib4_rt, false);
+	nsim_fib_account(&data->ipv4.fib, false);
+	nsim_fib4_rt_destroy(fib4_rt);
+}
+
+static void nsim_fib6_rt_free(struct nsim_fib_rt *fib_rt,
+			      struct nsim_fib_data *data)
+{
+	struct nsim_fib6_rt *fib6_rt;
+
+	fib6_rt = container_of(fib_rt, struct nsim_fib6_rt, common);
+	nsim_fib6_rt_hw_flags_set(data, fib6_rt, false);
+	nsim_fib_account(&data->ipv6.fib, false);
+	nsim_fib6_rt_destroy(fib6_rt);
+}
+
+static void nsim_fib_rt_free(void *ptr, void *arg)
+{
+	struct nsim_fib_rt *fib_rt = ptr;
+	struct nsim_fib_data *data = arg;
+
+	switch (fib_rt->key.family) {
+	case AF_INET:
+		nsim_fib4_rt_free(fib_rt, data);
+		break;
+	case AF_INET6:
+		nsim_fib6_rt_free(fib_rt, data);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+	}
+}
+
+/* inconsistent dump, trying again */
+static void nsim_fib_dump_inconsistent(struct notifier_block *nb)
+{
+	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
+						  fib_nb);
+	struct nsim_fib_rt *fib_rt, *fib_rt_tmp;
+
+	/* Flush the work to make sure there is no race with notifications. */
+	flush_work(&data->fib_event_work);
+
+	/* The notifier block is still not registered, so we do not need to
+	 * take any locks here.
+	 */
+	list_for_each_entry_safe(fib_rt, fib_rt_tmp, &data->fib_rt_list, list) {
+		rhashtable_remove_fast(&data->fib_rt_ht, &fib_rt->ht_node,
+				       nsim_fib_rt_ht_params);
+		nsim_fib_rt_free(fib_rt, data);
+	}
+
+	atomic64_set(&data->ipv4.rules.num, 0ULL);
+	atomic64_set(&data->ipv6.rules.num, 0ULL);
+}
+
+static struct nsim_nexthop *nsim_nexthop_create(struct nsim_fib_data *data,
+						struct nh_notifier_info *info)
+{
+	struct nsim_nexthop *nexthop;
+	u64 occ = 0;
+	int i;
+
+	nexthop = kzalloc(sizeof(*nexthop), GFP_KERNEL);
+	if (!nexthop)
+		return ERR_PTR(-ENOMEM);
+
+	nexthop->id = info->id;
+
+	/* Determine the number of nexthop entries the new nexthop will
+	 * occupy.
+	 */
+
+	switch (info->type) {
+	case NH_NOTIFIER_INFO_TYPE_SINGLE:
+		occ = 1;
+		break;
+	case NH_NOTIFIER_INFO_TYPE_GRP:
+		for (i = 0; i < info->nh_grp->num_nh; i++)
+			occ += info->nh_grp->nh_entries[i].weight;
+		break;
+	case NH_NOTIFIER_INFO_TYPE_RES_TABLE:
+		occ = info->nh_res_table->num_nh_buckets;
+		nexthop->is_resilient = true;
+		break;
+	default:
+		NL_SET_ERR_MSG_MOD(info->extack, "Unsupported nexthop type");
+		kfree(nexthop);
+		return ERR_PTR(-EOPNOTSUPP);
+	}
+
+	nexthop->occ = occ;
+	return nexthop;
+}
+
+static void nsim_nexthop_destroy(struct nsim_nexthop *nexthop)
+{
+	kfree(nexthop);
+}
+
+static int nsim_nexthop_account(struct nsim_fib_data *data, u64 occ,
+				bool add, struct netlink_ext_ack *extack)
+{
+	int i, err = 0;
+
+	if (add) {
+		for (i = 0; i < occ; i++)
+			if (!atomic64_add_unless(&data->nexthops.num, 1,
+						 data->nexthops.max)) {
+				err = -ENOSPC;
+				NL_SET_ERR_MSG_MOD(extack, "Exceeded number of supported nexthops");
+				goto err_num_decrease;
+			}
+	} else {
+		if (WARN_ON(occ > atomic64_read(&data->nexthops.num)))
+			return -EINVAL;
+		atomic64_sub(occ, &data->nexthops.num);
+	}
+
+	return err;
+
+err_num_decrease:
+	atomic64_sub(i, &data->nexthops.num);
+	return err;
+
+}
+
+static void nsim_nexthop_hw_flags_set(struct net *net,
+				      const struct nsim_nexthop *nexthop,
+				      bool trap)
+{
+	int i;
+
+	nexthop_set_hw_flags(net, nexthop->id, false, trap);
+
+	if (!nexthop->is_resilient)
+		return;
+
+	for (i = 0; i < nexthop->occ; i++)
+		nexthop_bucket_set_hw_flags(net, nexthop->id, i, false, trap);
+}
+
+static int nsim_nexthop_add(struct nsim_fib_data *data,
+			    struct nsim_nexthop *nexthop,
+			    struct netlink_ext_ack *extack)
+{
+	struct net *net = devlink_net(data->devlink);
+	int err;
+
+	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
+	if (err)
+		return err;
+
+	err = rhashtable_insert_fast(&data->nexthop_ht, &nexthop->ht_node,
+				     nsim_nexthop_ht_params);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Failed to insert nexthop");
+		goto err_nexthop_dismiss;
+	}
+
+	nsim_nexthop_hw_flags_set(net, nexthop, true);
+
+	return 0;
+
+err_nexthop_dismiss:
+	nsim_nexthop_account(data, nexthop->occ, false, extack);
+	return err;
+}
+
+static int nsim_nexthop_replace(struct nsim_fib_data *data,
+				struct nsim_nexthop *nexthop,
+				struct nsim_nexthop *nexthop_old,
+				struct netlink_ext_ack *extack)
+{
+	struct net *net = devlink_net(data->devlink);
+	int err;
+
+	err = nsim_nexthop_account(data, nexthop->occ, true, extack);
+	if (err)
+		return err;
+
+	err = rhashtable_replace_fast(&data->nexthop_ht,
+				      &nexthop_old->ht_node, &nexthop->ht_node,
+				      nsim_nexthop_ht_params);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack, "Failed to replace nexthop");
+		goto err_nexthop_dismiss;
+	}
+
+	nsim_nexthop_hw_flags_set(net, nexthop, true);
+	nsim_nexthop_account(data, nexthop_old->occ, false, extack);
+	nsim_nexthop_destroy(nexthop_old);
+
+	return 0;
+
+err_nexthop_dismiss:
+	nsim_nexthop_account(data, nexthop->occ, false, extack);
+	return err;
+}
+
+static int nsim_nexthop_insert(struct nsim_fib_data *data,
+			       struct nh_notifier_info *info)
+{
+	struct nsim_nexthop *nexthop, *nexthop_old;
+	int err;
+
+	nexthop = nsim_nexthop_create(data, info);
+	if (IS_ERR(nexthop))
+		return PTR_ERR(nexthop);
+
+	nexthop_old = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
+					     nsim_nexthop_ht_params);
+	if (!nexthop_old)
+		err = nsim_nexthop_add(data, nexthop, info->extack);
+	else
+		err = nsim_nexthop_replace(data, nexthop, nexthop_old,
+					   info->extack);
+
+	if (err)
+		nsim_nexthop_destroy(nexthop);
+
+	return err;
+}
+
+static void nsim_nexthop_remove(struct nsim_fib_data *data,
+				struct nh_notifier_info *info)
+{
+	struct nsim_nexthop *nexthop;
+
+	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &info->id,
+					 nsim_nexthop_ht_params);
+	if (!nexthop)
+		return;
+
+	rhashtable_remove_fast(&data->nexthop_ht, &nexthop->ht_node,
+			       nsim_nexthop_ht_params);
+	nsim_nexthop_account(data, nexthop->occ, false, info->extack);
+	nsim_nexthop_destroy(nexthop);
+}
+
+static int nsim_nexthop_res_table_pre_replace(struct nsim_fib_data *data,
+					      struct nh_notifier_info *info)
+{
+	if (data->fail_res_nexthop_group_replace) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace a resilient nexthop group");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int nsim_nexthop_bucket_replace(struct nsim_fib_data *data,
+				       struct nh_notifier_info *info)
+{
+	if (data->fail_nexthop_bucket_replace) {
+		NL_SET_ERR_MSG_MOD(info->extack, "Failed to replace nexthop bucket");
+		return -EINVAL;
+	}
+
+	nexthop_bucket_set_hw_flags(info->net, info->id,
+				    info->nh_res_bucket->bucket_index,
+				    false, true);
+
+	return 0;
+}
+
+static int nsim_nexthop_event_nb(struct notifier_block *nb, unsigned long event,
+				 void *ptr)
+{
+	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
+						  nexthop_nb);
+	struct nh_notifier_info *info = ptr;
+	int err = 0;
+
+	mutex_lock(&data->nh_lock);
+	switch (event) {
+	case NEXTHOP_EVENT_REPLACE:
+		err = nsim_nexthop_insert(data, info);
+		break;
+	case NEXTHOP_EVENT_DEL:
+		nsim_nexthop_remove(data, info);
+		break;
+	case NEXTHOP_EVENT_RES_TABLE_PRE_REPLACE:
+		err = nsim_nexthop_res_table_pre_replace(data, info);
+		break;
+	case NEXTHOP_EVENT_BUCKET_REPLACE:
+		err = nsim_nexthop_bucket_replace(data, info);
+		break;
+	default:
+		break;
+	}
+
+	mutex_unlock(&data->nh_lock);
+	return notifier_from_errno(err);
+}
+
+static void nsim_nexthop_free(void *ptr, void *arg)
+{
+	struct nsim_nexthop *nexthop = ptr;
+	struct nsim_fib_data *data = arg;
+	struct net *net;
+
+	net = devlink_net(data->devlink);
+	nsim_nexthop_hw_flags_set(net, nexthop, false);
+	nsim_nexthop_account(data, nexthop->occ, false, NULL);
+	nsim_nexthop_destroy(nexthop);
+}
+
+static ssize_t nsim_nexthop_bucket_activity_write(struct file *file,
+						  const char __user *user_buf,
+						  size_t size, loff_t *ppos)
+{
+	struct nsim_fib_data *data = file->private_data;
+	struct net *net = devlink_net(data->devlink);
+	struct nsim_nexthop *nexthop;
+	unsigned long *activity;
+	loff_t pos = *ppos;
+	u16 bucket_index;
+	char buf[128];
+	int err = 0;
+	u32 nhid;
+
+	if (pos != 0)
+		return -EINVAL;
+	if (size > sizeof(buf))
+		return -EINVAL;
+	if (copy_from_user(buf, user_buf, size))
+		return -EFAULT;
+	if (sscanf(buf, "%u %hu", &nhid, &bucket_index) != 2)
+		return -EINVAL;
+
+	rtnl_lock();
+
+	nexthop = rhashtable_lookup_fast(&data->nexthop_ht, &nhid,
+					 nsim_nexthop_ht_params);
+	if (!nexthop || !nexthop->is_resilient ||
+	    bucket_index >= nexthop->occ) {
+		err = -EINVAL;
+		goto out;
+	}
+
+	activity = bitmap_zalloc(nexthop->occ, GFP_KERNEL);
+	if (!activity) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	bitmap_set(activity, bucket_index, 1);
+	nexthop_res_grp_activity_update(net, nhid, nexthop->occ, activity);
+	bitmap_free(activity);
+
+out:
+	rtnl_unlock();
+
+	*ppos = size;
+	return err ?: size;
+}
+
+static const struct file_operations nsim_nexthop_bucket_activity_fops = {
+	.open = simple_open,
+	.write = nsim_nexthop_bucket_activity_write,
+	.llseek = no_llseek,
+	.owner = THIS_MODULE,
+};
+
+static u64 nsim_fib_ipv4_resource_occ_get(void *priv)
+{
+	struct nsim_fib_data *data = priv;
+
+	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB, false);
+}
+
+static u64 nsim_fib_ipv4_rules_res_occ_get(void *priv)
+{
+	struct nsim_fib_data *data = priv;
+
+	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV4_FIB_RULES, false);
+}
+
+static u64 nsim_fib_ipv6_resource_occ_get(void *priv)
+{
+	struct nsim_fib_data *data = priv;
+
+	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB, false);
+}
+
+static u64 nsim_fib_ipv6_rules_res_occ_get(void *priv)
+{
+	struct nsim_fib_data *data = priv;
+
+	return nsim_fib_get_val(data, NSIM_RESOURCE_IPV6_FIB_RULES, false);
+}
+
+static u64 nsim_fib_nexthops_res_occ_get(void *priv)
+{
+	struct nsim_fib_data *data = priv;
+
+	return nsim_fib_get_val(data, NSIM_RESOURCE_NEXTHOPS, false);
+}
+
+static void nsim_fib_set_max_all(struct nsim_fib_data *data,
+				 struct devlink *devlink)
+{
+	static const enum nsim_resource_id res_ids[] = {
+		NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES,
+		NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES,
+		NSIM_RESOURCE_NEXTHOPS,
+	};
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(res_ids); i++) {
+		int err;
+		u64 val;
+
+		err = devl_resource_size_get(devlink, res_ids[i], &val);
+		if (err)
+			val = (u64) -1;
+		nsim_fib_set_max(data, res_ids[i], val);
+	}
+}
+
+static void nsim_fib_event_work(struct work_struct *work)
+{
+	struct nsim_fib_data *data = container_of(work, struct nsim_fib_data,
+						  fib_event_work);
+	struct nsim_fib_event *fib_event, *next_fib_event;
+
+	LIST_HEAD(fib_event_queue);
+
+	spin_lock_bh(&data->fib_event_queue_lock);
+	list_splice_init(&data->fib_event_queue, &fib_event_queue);
+	spin_unlock_bh(&data->fib_event_queue_lock);
+
+	mutex_lock(&data->fib_lock);
+	list_for_each_entry_safe(fib_event, next_fib_event, &fib_event_queue,
+				 list) {
+		nsim_fib_event(fib_event);
+		list_del(&fib_event->list);
+		kfree(fib_event);
+		cond_resched();
+	}
+	mutex_unlock(&data->fib_lock);
+}
+
+static void nsim_fib_flush_work(struct work_struct *work)
+{
+	struct nsim_fib_data *data = container_of(work, struct nsim_fib_data,
+						  fib_flush_work);
+	struct nsim_fib_rt *fib_rt, *fib_rt_tmp;
+
+	/* Process pending work. */
+	flush_work(&data->fib_event_work);
+
+	mutex_lock(&data->fib_lock);
+	list_for_each_entry_safe(fib_rt, fib_rt_tmp, &data->fib_rt_list, list) {
+		rhashtable_remove_fast(&data->fib_rt_ht, &fib_rt->ht_node,
+				       nsim_fib_rt_ht_params);
+		nsim_fib_rt_free(fib_rt, data);
+	}
+	mutex_unlock(&data->fib_lock);
+}
+
+static int
+nsim_fib_debugfs_init(struct nsim_fib_data *data, struct nsim_dev *nsim_dev)
+{
+	data->ddir = debugfs_create_dir("fib", nsim_dev->ddir);
+	if (IS_ERR(data->ddir))
+		return PTR_ERR(data->ddir);
+
+	data->fail_route_offload = false;
+	debugfs_create_bool("fail_route_offload", 0600, data->ddir,
+			    &data->fail_route_offload);
+
+	data->fail_res_nexthop_group_replace = false;
+	debugfs_create_bool("fail_res_nexthop_group_replace", 0600, data->ddir,
+			    &data->fail_res_nexthop_group_replace);
+
+	data->fail_nexthop_bucket_replace = false;
+	debugfs_create_bool("fail_nexthop_bucket_replace", 0600, data->ddir,
+			    &data->fail_nexthop_bucket_replace);
+
+	debugfs_create_file("nexthop_bucket_activity", 0200, data->ddir,
+			    data, &nsim_nexthop_bucket_activity_fops);
+
+	data->fail_route_delete = false;
+	debugfs_create_bool("fail_route_delete", 0600, data->ddir,
+			    &data->fail_route_delete);
+	return 0;
+}
+
+static void nsim_fib_debugfs_exit(struct nsim_fib_data *data)
+{
+	debugfs_remove_recursive(data->ddir);
+}
+
+struct nsim_fib_data *nsim_fib_create(struct devlink *devlink,
+				      struct netlink_ext_ack *extack)
+{
+	struct nsim_fib_data *data;
+	struct nsim_dev *nsim_dev;
+	int err;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
+	data->devlink = devlink;
+
+	nsim_dev = devlink_priv(devlink);
+	err = nsim_fib_debugfs_init(data, nsim_dev);
+	if (err)
+		goto err_data_free;
+
+	mutex_init(&data->nh_lock);
+	err = rhashtable_init(&data->nexthop_ht, &nsim_nexthop_ht_params);
+	if (err)
+		goto err_debugfs_exit;
+
+	mutex_init(&data->fib_lock);
+	INIT_LIST_HEAD(&data->fib_rt_list);
+	err = rhashtable_init(&data->fib_rt_ht, &nsim_fib_rt_ht_params);
+	if (err)
+		goto err_rhashtable_nexthop_destroy;
+
+	INIT_WORK(&data->fib_event_work, nsim_fib_event_work);
+	INIT_WORK(&data->fib_flush_work, nsim_fib_flush_work);
+	INIT_LIST_HEAD(&data->fib_event_queue);
+	spin_lock_init(&data->fib_event_queue_lock);
+
+	nsim_fib_set_max_all(data, devlink);
+
+	data->nexthop_nb.notifier_call = nsim_nexthop_event_nb;
+	err = register_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb,
+					extack);
+	if (err) {
+		pr_err("Failed to register nexthop notifier\n");
+		goto err_rhashtable_fib_destroy;
+	}
+
+	data->fib_nb.notifier_call = nsim_fib_event_nb;
+	err = register_fib_notifier(devlink_net(devlink), &data->fib_nb,
+				    nsim_fib_dump_inconsistent, extack);
+	if (err) {
+		pr_err("Failed to register fib notifier\n");
+		goto err_nexthop_nb_unregister;
+	}
+
+	devl_resource_occ_get_register(devlink,
+				       NSIM_RESOURCE_IPV4_FIB,
+				       nsim_fib_ipv4_resource_occ_get,
+				       data);
+	devl_resource_occ_get_register(devlink,
+				       NSIM_RESOURCE_IPV4_FIB_RULES,
+				       nsim_fib_ipv4_rules_res_occ_get,
+				       data);
+	devl_resource_occ_get_register(devlink,
+				       NSIM_RESOURCE_IPV6_FIB,
+				       nsim_fib_ipv6_resource_occ_get,
+				       data);
+	devl_resource_occ_get_register(devlink,
+				       NSIM_RESOURCE_IPV6_FIB_RULES,
+				       nsim_fib_ipv6_rules_res_occ_get,
+				       data);
+	devl_resource_occ_get_register(devlink,
+				       NSIM_RESOURCE_NEXTHOPS,
+				       nsim_fib_nexthops_res_occ_get,
+				       data);
+	return data;
+
+err_nexthop_nb_unregister:
+	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
+err_rhashtable_fib_destroy:
+	cancel_work_sync(&data->fib_flush_work);
+	flush_work(&data->fib_event_work);
+	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
+				    data);
+err_rhashtable_nexthop_destroy:
+	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
+				    data);
+	mutex_destroy(&data->fib_lock);
+err_debugfs_exit:
+	mutex_destroy(&data->nh_lock);
+	nsim_fib_debugfs_exit(data);
+err_data_free:
+	kfree(data);
+	return ERR_PTR(err);
+}
+
+void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *data)
+{
+	devl_resource_occ_get_unregister(devlink,
+					 NSIM_RESOURCE_NEXTHOPS);
+	devl_resource_occ_get_unregister(devlink,
+					 NSIM_RESOURCE_IPV6_FIB_RULES);
+	devl_resource_occ_get_unregister(devlink,
+					 NSIM_RESOURCE_IPV6_FIB);
+	devl_resource_occ_get_unregister(devlink,
+					 NSIM_RESOURCE_IPV4_FIB_RULES);
+	devl_resource_occ_get_unregister(devlink,
+					 NSIM_RESOURCE_IPV4_FIB);
+	unregister_fib_notifier(devlink_net(devlink), &data->fib_nb);
+	unregister_nexthop_notifier(devlink_net(devlink), &data->nexthop_nb);
+	cancel_work_sync(&data->fib_flush_work);
+	flush_work(&data->fib_event_work);
+	rhashtable_free_and_destroy(&data->fib_rt_ht, nsim_fib_rt_free,
+				    data);
+	rhashtable_free_and_destroy(&data->nexthop_ht, nsim_nexthop_free,
+				    data);
+	WARN_ON_ONCE(!list_empty(&data->fib_event_queue));
+	WARN_ON_ONCE(!list_empty(&data->fib_rt_list));
+	mutex_destroy(&data->fib_lock);
+	mutex_destroy(&data->nh_lock);
+	nsim_fib_debugfs_exit(data);
+	kfree(data);
+}