Merge branch 'mlxsw-Reflect-nexthop-status-changes'

Jiri Pirko says:

====================
mlxsw: Reflect nexthop status changes

Ido says:

When the kernel forwards IPv4 packets via multipath routes it doesn't
consider nexthops that are dead or linkdown. For example, if the nexthop
netdev is administratively down or doesn't have a carrier.

Devices capable of offloading such multipath routes need to be made
aware of changes in the reflected nexthops' status. Otherwise, the
device might forward packets via non-functional nexthops, resulting in
packet loss. This patchset aims to fix that.

The first 11 patches deal with the necessary restructuring in the
mlxsw driver, so that it's able to correctly add and remove nexthops
from the device's adjacency table.

The 12th patch adds the NH_{ADD,DEL} events to the FIB notification
chain. These notifications are sent whenever the kernel decides to add
or remove a nexthop from the forwarding plane.

Finally, the last three patches add support for these events in the
mlxsw driver, which is currently the only driver capable of offloading
multipath routes.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -3473,6 +3473,8 @@ mlxsw_sp_rif_alloc(u16 rif, struct net_device *l3_dev, struct mlxsw_sp_fid *f)
 	if (!r)
 		return NULL;
 
+	INIT_LIST_HEAD(&r->nexthop_list);
+	INIT_LIST_HEAD(&r->neigh_list);
 	ether_addr_copy(r->addr, l3_dev->dev_addr);
 	r->mtu = l3_dev->mtu;
 	r->ref_count = 1;
@@ -3541,6 +3543,8 @@ static void mlxsw_sp_vport_rif_sp_destroy(struct mlxsw_sp_port *mlxsw_sp_vport,
 	u16 fid = f->fid;
 	u16 rif = r->rif;
 
+	mlxsw_sp_router_rif_gone_sync(mlxsw_sp, r);
+
 	mlxsw_sp->rifs[rif] = NULL;
 	f->r = NULL;
 
@@ -3770,6 +3774,8 @@ void mlxsw_sp_rif_bridge_destroy(struct mlxsw_sp *mlxsw_sp,
 	struct mlxsw_sp_fid *f = r->f;
 	u16 rif = r->rif;
 
+	mlxsw_sp_router_rif_gone_sync(mlxsw_sp, r);
+
 	mlxsw_sp->rifs[rif] = NULL;
 	f->r = NULL;
 

drivers/net/ethernet/mellanox/mlxsw/spectrum.h

@@ -108,6 +108,8 @@ struct mlxsw_sp_fid {
 };
 
 struct mlxsw_sp_rif {
+	struct list_head nexthop_list;
+	struct list_head neigh_list;
 	struct net_device *dev;
 	unsigned int ref_count;
 	struct mlxsw_sp_fid *f;
@@ -254,13 +256,14 @@ struct mlxsw_sp_router {
 	struct mlxsw_sp_lpm_tree lpm_trees[MLXSW_SP_LPM_TREE_COUNT];
 	struct mlxsw_sp_vr *vrs;
 	struct rhashtable neigh_ht;
+	struct rhashtable nexthop_group_ht;
+	struct rhashtable nexthop_ht;
 	struct {
 		struct delayed_work dw;
 		unsigned long interval;	/* ms */
 	} neighs_update;
 	struct delayed_work nexthop_probe_dw;
 #define MLXSW_SP_UNRESOLVED_NH_PROBE_INTERVAL 5000 /* ms */
-	struct list_head nexthop_group_list;
 	struct list_head nexthop_neighs_list;
 	bool aborted;
 };
@@ -601,6 +604,8 @@ int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp);
 void mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp);
 int mlxsw_sp_router_netevent_event(struct notifier_block *unused,
 				   unsigned long event, void *ptr);
+void mlxsw_sp_router_rif_gone_sync(struct mlxsw_sp *mlxsw_sp,
+				   struct mlxsw_sp_rif *r);
 
 int mlxsw_sp_kvdl_alloc(struct mlxsw_sp *mlxsw_sp, unsigned int entry_count);
 void mlxsw_sp_kvdl_free(struct mlxsw_sp *mlxsw_sp, int entry_index);

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -127,11 +127,10 @@ struct mlxsw_sp_fib_entry {
 	struct mlxsw_sp_fib_key key;
 	enum mlxsw_sp_fib_entry_type type;
 	unsigned int ref_count;
-	u16 rif; /* used for action local */
 	struct mlxsw_sp_vr *vr;
-	struct fib_info *fi;
 	struct list_head nexthop_group_node;
 	struct mlxsw_sp_nexthop_group *nh_group;
+	bool offloaded;
 };
 
 struct mlxsw_sp_fib {
@@ -610,6 +609,7 @@ struct mlxsw_sp_neigh_key {
 };
 
 struct mlxsw_sp_neigh_entry {
+	struct list_head rif_list_node;
 	struct rhash_head ht_node;
 	struct mlxsw_sp_neigh_key key;
 	u16 rif;
@@ -686,6 +686,8 @@ mlxsw_sp_neigh_entry_create(struct mlxsw_sp *mlxsw_sp, struct neighbour *n)
 	if (err)
 		goto err_neigh_entry_insert;
 
+	list_add(&neigh_entry->rif_list_node, &r->neigh_list);
+
 	return neigh_entry;
 
 err_neigh_entry_insert:
@@ -697,6 +699,7 @@ static void
 mlxsw_sp_neigh_entry_destroy(struct mlxsw_sp *mlxsw_sp,
 			     struct mlxsw_sp_neigh_entry *neigh_entry)
 {
+	list_del(&neigh_entry->rif_list_node);
 	mlxsw_sp_neigh_entry_remove(mlxsw_sp, neigh_entry);
 	mlxsw_sp_neigh_entry_free(neigh_entry);
 }
@@ -1090,11 +1093,40 @@ static void mlxsw_sp_neigh_fini(struct mlxsw_sp *mlxsw_sp)
 	rhashtable_destroy(&mlxsw_sp->router.neigh_ht);
 }
 
+static int mlxsw_sp_neigh_rif_flush(struct mlxsw_sp *mlxsw_sp,
+				    const struct mlxsw_sp_rif *r)
+{
+	char rauht_pl[MLXSW_REG_RAUHT_LEN];
+
+	mlxsw_reg_rauht_pack(rauht_pl, MLXSW_REG_RAUHT_OP_WRITE_DELETE_ALL,
+			     r->rif, r->addr);
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(rauht), rauht_pl);
+}
+
+static void mlxsw_sp_neigh_rif_gone_sync(struct mlxsw_sp *mlxsw_sp,
+					 struct mlxsw_sp_rif *r)
+{
+	struct mlxsw_sp_neigh_entry *neigh_entry, *tmp;
+
+	mlxsw_sp_neigh_rif_flush(mlxsw_sp, r);
+	list_for_each_entry_safe(neigh_entry, tmp, &r->neigh_list,
+				 rif_list_node)
+		mlxsw_sp_neigh_entry_destroy(mlxsw_sp, neigh_entry);
+}
+
+struct mlxsw_sp_nexthop_key {
+	struct fib_nh *fib_nh;
+};
+
 struct mlxsw_sp_nexthop {
 	struct list_head neigh_list_node; /* member of neigh entry list */
+	struct list_head rif_list_node;
 	struct mlxsw_sp_nexthop_group *nh_grp; /* pointer back to the group
 						* this belongs to
 						*/
+	struct rhash_head ht_node;
+	struct mlxsw_sp_nexthop_key key;
+	struct mlxsw_sp_rif *r;
 	u8 should_offload:1, /* set indicates this neigh is connected and
 			      * should be put to KVD linear area of this group.
 			      */
@@ -1107,16 +1139,81 @@ struct mlxsw_sp_nexthop {
 	struct mlxsw_sp_neigh_entry *neigh_entry;
 };
 
+struct mlxsw_sp_nexthop_group_key {
+	struct fib_info *fi;
+};
+
 struct mlxsw_sp_nexthop_group {
-	struct list_head list; /* node in mlxsw->router.nexthop_group_list */
+	struct rhash_head ht_node;
 	struct list_head fib_list; /* list of fib entries that use this group */
-	u8 adj_index_valid:1;
+	struct mlxsw_sp_nexthop_group_key key;
+	u8 adj_index_valid:1,
+	   gateway:1; /* routes using the group use a gateway */
 	u32 adj_index;
 	u16 ecmp_size;
 	u16 count;
 	struct mlxsw_sp_nexthop nexthops[0];
+#define nh_rif	nexthops[0].r
+};
+
+static const struct rhashtable_params mlxsw_sp_nexthop_group_ht_params = {
+	.key_offset = offsetof(struct mlxsw_sp_nexthop_group, key),
+	.head_offset = offsetof(struct mlxsw_sp_nexthop_group, ht_node),
+	.key_len = sizeof(struct mlxsw_sp_nexthop_group_key),
+};
+
+static int mlxsw_sp_nexthop_group_insert(struct mlxsw_sp *mlxsw_sp,
+					 struct mlxsw_sp_nexthop_group *nh_grp)
+{
+	return rhashtable_insert_fast(&mlxsw_sp->router.nexthop_group_ht,
+				      &nh_grp->ht_node,
+				      mlxsw_sp_nexthop_group_ht_params);
+}
+
+static void mlxsw_sp_nexthop_group_remove(struct mlxsw_sp *mlxsw_sp,
+					  struct mlxsw_sp_nexthop_group *nh_grp)
+{
+	rhashtable_remove_fast(&mlxsw_sp->router.nexthop_group_ht,
+			       &nh_grp->ht_node,
+			       mlxsw_sp_nexthop_group_ht_params);
+}
+
+static struct mlxsw_sp_nexthop_group *
+mlxsw_sp_nexthop_group_lookup(struct mlxsw_sp *mlxsw_sp,
+			      struct mlxsw_sp_nexthop_group_key key)
+{
+	return rhashtable_lookup_fast(&mlxsw_sp->router.nexthop_group_ht, &key,
+				      mlxsw_sp_nexthop_group_ht_params);
+}
+
+static const struct rhashtable_params mlxsw_sp_nexthop_ht_params = {
+	.key_offset = offsetof(struct mlxsw_sp_nexthop, key),
+	.head_offset = offsetof(struct mlxsw_sp_nexthop, ht_node),
+	.key_len = sizeof(struct mlxsw_sp_nexthop_key),
 };
 
+static int mlxsw_sp_nexthop_insert(struct mlxsw_sp *mlxsw_sp,
+				   struct mlxsw_sp_nexthop *nh)
+{
+	return rhashtable_insert_fast(&mlxsw_sp->router.nexthop_ht,
+				      &nh->ht_node, mlxsw_sp_nexthop_ht_params);
+}
+
+static void mlxsw_sp_nexthop_remove(struct mlxsw_sp *mlxsw_sp,
+				    struct mlxsw_sp_nexthop *nh)
+{
+	rhashtable_remove_fast(&mlxsw_sp->router.nexthop_ht, &nh->ht_node,
+			       mlxsw_sp_nexthop_ht_params);
+}
+
+static struct mlxsw_sp_nexthop *
+mlxsw_sp_nexthop_lookup(struct mlxsw_sp *mlxsw_sp,
+			struct mlxsw_sp_nexthop_key key)
+{
+	return rhashtable_lookup_fast(&mlxsw_sp->router.nexthop_ht, &key,
+				      mlxsw_sp_nexthop_ht_params);
+}
+
 static int mlxsw_sp_adj_index_mass_update_vr(struct mlxsw_sp *mlxsw_sp,
 					     struct mlxsw_sp_vr *vr,
 					     u32 adj_index, u16 ecmp_size,
@@ -1231,6 +1328,11 @@ mlxsw_sp_nexthop_group_refresh(struct mlxsw_sp *mlxsw_sp,
 	int i;
 	int err;
 
+	if (!nh_grp->gateway) {
+		mlxsw_sp_nexthop_fib_entries_update(mlxsw_sp, nh_grp);
+		return;
+	}
+
 	for (i = 0; i < nh_grp->count; i++) {
 		nh = &nh_grp->nexthops[i];
 
@@ -1340,24 +1442,45 @@ mlxsw_sp_nexthop_neigh_update(struct mlxsw_sp *mlxsw_sp,
 	}
 }
 
-static int mlxsw_sp_nexthop_init(struct mlxsw_sp *mlxsw_sp,
-				 struct mlxsw_sp_nexthop_group *nh_grp,
-				 struct mlxsw_sp_nexthop *nh,
-				 struct fib_nh *fib_nh)
+static void mlxsw_sp_nexthop_rif_init(struct mlxsw_sp_nexthop *nh,
+				      struct mlxsw_sp_rif *r)
+{
+	if (nh->r)
+		return;
+
+	nh->r = r;
+	list_add(&nh->rif_list_node, &r->nexthop_list);
+}
+
+static void mlxsw_sp_nexthop_rif_fini(struct mlxsw_sp_nexthop *nh)
+{
+	if (!nh->r)
+		return;
+
+	list_del(&nh->rif_list_node);
+	nh->r = NULL;
+}
+
+static int mlxsw_sp_nexthop_neigh_init(struct mlxsw_sp *mlxsw_sp,
+				       struct mlxsw_sp_nexthop *nh)
 {
 	struct mlxsw_sp_neigh_entry *neigh_entry;
-	struct net_device *dev = fib_nh->nh_dev;
+	struct fib_nh *fib_nh = nh->key.fib_nh;
 	struct neighbour *n;
 	u8 nud_state, dead;
+	int err;
+
+	if (!nh->nh_grp->gateway || nh->neigh_entry)
+		return 0;
 
 	/* Take a reference of neigh here ensuring that neigh would
 	 * not be detructed before the nexthop entry is finished.
 	 * The reference is taken either in neigh_lookup() or
 	 * in neigh_create() in case n is not found.
 	 */
-	n = neigh_lookup(&arp_tbl, &fib_nh->nh_gw, dev);
+	n = neigh_lookup(&arp_tbl, &fib_nh->nh_gw, fib_nh->nh_dev);
 	if (!n) {
-		n = neigh_create(&arp_tbl, &fib_nh->nh_gw, dev);
+		n = neigh_create(&arp_tbl, &fib_nh->nh_gw, fib_nh->nh_dev);
 		if (IS_ERR(n))
 			return PTR_ERR(n);
 		neigh_event_send(n, NULL);
@@ -1366,8 +1489,8 @@ static int mlxsw_sp_nexthop_init(struct mlxsw_sp *mlxsw_sp,
 	if (!neigh_entry) {
 		neigh_entry = mlxsw_sp_neigh_entry_create(mlxsw_sp, n);
 		if (IS_ERR(neigh_entry)) {
-			neigh_release(n);
-			return -EINVAL;
+			err = -EINVAL;
+			goto err_neigh_entry_create;
 		}
 	}
 
@@ -1378,7 +1501,6 @@ static int mlxsw_sp_nexthop_init(struct mlxsw_sp *mlxsw_sp,
 		list_add_tail(&neigh_entry->nexthop_neighs_list_node,
 			      &mlxsw_sp->router.nexthop_neighs_list);
 
-	nh->nh_grp = nh_grp;
 	nh->neigh_entry = neigh_entry;
 	list_add_tail(&nh->neigh_list_node, &neigh_entry->nexthop_list);
 	read_lock_bh(&n->lock);
@@ -1388,22 +1510,31 @@ static int mlxsw_sp_nexthop_init(struct mlxsw_sp *mlxsw_sp,
 	__mlxsw_sp_nexthop_neigh_update(nh, !(nud_state & NUD_VALID && !dead));
 
 	return 0;
+
+err_neigh_entry_create:
+	neigh_release(n);
+	return err;
 }
 
-static void mlxsw_sp_nexthop_fini(struct mlxsw_sp *mlxsw_sp,
-				  struct mlxsw_sp_nexthop *nh)
+static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp,
+					struct mlxsw_sp_nexthop *nh)
 {
 	struct mlxsw_sp_neigh_entry *neigh_entry = nh->neigh_entry;
-	struct neighbour *n = neigh_entry->key.n;
+	struct neighbour *n;
+
+	if (!neigh_entry)
+		return;
+	n = neigh_entry->key.n;
 
 	__mlxsw_sp_nexthop_neigh_update(nh, true);
 	list_del(&nh->neigh_list_node);
+	nh->neigh_entry = NULL;
 
 	/* If that is the last nexthop connected to that neigh, remove from
 	 * nexthop_neighs_list
 	 */
-	if (list_empty(&nh->neigh_entry->nexthop_list))
-		list_del(&nh->neigh_entry->nexthop_neighs_list_node);
+	if (list_empty(&neigh_entry->nexthop_list))
+		list_del(&neigh_entry->nexthop_neighs_list_node);
 
 	if (!neigh_entry->connected && list_empty(&neigh_entry->nexthop_list))
 		mlxsw_sp_neigh_entry_destroy(mlxsw_sp, neigh_entry);
@@ -1411,6 +1542,90 @@ static void mlxsw_sp_nexthop_fini(struct mlxsw_sp *mlxsw_sp,
 	neigh_release(n);
 }
 
+static int mlxsw_sp_nexthop_init(struct mlxsw_sp *mlxsw_sp,
+				 struct mlxsw_sp_nexthop_group *nh_grp,
+				 struct mlxsw_sp_nexthop *nh,
+				 struct fib_nh *fib_nh)
+{
+	struct net_device *dev = fib_nh->nh_dev;
+	struct mlxsw_sp_rif *r;
+	int err;
+
+	nh->nh_grp = nh_grp;
+	nh->key.fib_nh = fib_nh;
+	err = mlxsw_sp_nexthop_insert(mlxsw_sp, nh);
+	if (err)
+		return err;
+
+	r = mlxsw_sp_rif_find_by_dev(mlxsw_sp, dev);
+	if (!r)
+		return 0;
+	mlxsw_sp_nexthop_rif_init(nh, r);
+
+	err = mlxsw_sp_nexthop_neigh_init(mlxsw_sp, nh);
+	if (err)
+		goto err_nexthop_neigh_init;
+
+	return 0;
+
+err_nexthop_neigh_init:
+	mlxsw_sp_nexthop_remove(mlxsw_sp, nh);
+	return err;
+}
+
+static void mlxsw_sp_nexthop_fini(struct mlxsw_sp *mlxsw_sp,
+				  struct mlxsw_sp_nexthop *nh)
+{
+	mlxsw_sp_nexthop_neigh_fini(mlxsw_sp, nh);
+	mlxsw_sp_nexthop_rif_fini(nh);
+	mlxsw_sp_nexthop_remove(mlxsw_sp, nh);
+}
+
+static void mlxsw_sp_nexthop_event(struct mlxsw_sp *mlxsw_sp,
+				   unsigned long event, struct fib_nh *fib_nh)
+{
+	struct mlxsw_sp_nexthop_key key;
+	struct mlxsw_sp_nexthop *nh;
+	struct mlxsw_sp_rif *r;
+
+	if (mlxsw_sp->router.aborted)
+		return;
+
+	key.fib_nh = fib_nh;
+	nh = mlxsw_sp_nexthop_lookup(mlxsw_sp, key);
+	if (WARN_ON_ONCE(!nh))
+		return;
+
+	r = mlxsw_sp_rif_find_by_dev(mlxsw_sp, fib_nh->nh_dev);
+	if (!r)
+		return;
+
+	switch (event) {
+	case FIB_EVENT_NH_ADD:
+		mlxsw_sp_nexthop_rif_init(nh, r);
+		mlxsw_sp_nexthop_neigh_init(mlxsw_sp, nh);
+		break;
+	case FIB_EVENT_NH_DEL:
+		mlxsw_sp_nexthop_neigh_fini(mlxsw_sp, nh);
+		mlxsw_sp_nexthop_rif_fini(nh);
+		break;
+	}
+
+	mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh->nh_grp);
+}
+
+static void mlxsw_sp_nexthop_rif_gone_sync(struct mlxsw_sp *mlxsw_sp,
+					   struct mlxsw_sp_rif *r)
+{
+	struct mlxsw_sp_nexthop *nh, *tmp;
+
+	list_for_each_entry_safe(nh, tmp, &r->nexthop_list, rif_list_node) {
+		mlxsw_sp_nexthop_neigh_fini(mlxsw_sp, nh);
+		mlxsw_sp_nexthop_rif_fini(nh);
+		mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh->nh_grp);
+	}
+}
+
 static struct mlxsw_sp_nexthop_group *
 mlxsw_sp_nexthop_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
 {
@@ -1427,7 +1642,9 @@ mlxsw_sp_nexthop_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
 	if (!nh_grp)
 		return ERR_PTR(-ENOMEM);
 	INIT_LIST_HEAD(&nh_grp->fib_list);
+	nh_grp->gateway = fi->fib_nh->nh_scope == RT_SCOPE_LINK;
 	nh_grp->count = fi->fib_nhs;
+	nh_grp->key.fi = fi;
 	for (i = 0; i < nh_grp->count; i++) {
 		nh = &nh_grp->nexthops[i];
 		fib_nh = &fi->fib_nh[i];
@@ -1435,10 +1652,13 @@ mlxsw_sp_nexthop_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
 		if (err)
 			goto err_nexthop_init;
 	}
-	list_add_tail(&nh_grp->list, &mlxsw_sp->router.nexthop_group_list);
+	err = mlxsw_sp_nexthop_group_insert(mlxsw_sp, nh_grp);
+	if (err)
+		goto err_nexthop_group_insert;
 	mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh_grp);
 	return nh_grp;
 
+err_nexthop_group_insert:
 err_nexthop_init:
 	for (i--; i >= 0; i--)
 		mlxsw_sp_nexthop_fini(mlxsw_sp, nh);
@@ -1453,7 +1673,7 @@ mlxsw_sp_nexthop_group_destroy(struct mlxsw_sp *mlxsw_sp,
 	struct mlxsw_sp_nexthop *nh;
 	int i;
 
-	list_del(&nh_grp->list);
+	mlxsw_sp_nexthop_group_remove(mlxsw_sp, nh_grp);
 	for (i = 0; i < nh_grp->count; i++) {
 		nh = &nh_grp->nexthops[i];
 		mlxsw_sp_nexthop_fini(mlxsw_sp, nh);
@@ -1463,59 +1683,15 @@ mlxsw_sp_nexthop_group_destroy(struct mlxsw_sp *mlxsw_sp,
 	kfree(nh_grp);
 }
 
-static bool mlxsw_sp_nexthop_match(struct mlxsw_sp_nexthop *nh,
-				   struct fib_info *fi)
-{
-	int i;
-
-	for (i = 0; i < fi->fib_nhs; i++) {
-		struct fib_nh *fib_nh = &fi->fib_nh[i];
-		struct neighbour *n = nh->neigh_entry->key.n;
-
-		if (memcmp(n->primary_key, &fib_nh->nh_gw,
-			   sizeof(fib_nh->nh_gw)) == 0 &&
-		    n->dev == fib_nh->nh_dev)
-			return true;
-	}
-	return false;
-}
-
-static bool mlxsw_sp_nexthop_group_match(struct mlxsw_sp_nexthop_group *nh_grp,
-					 struct fib_info *fi)
-{
-	int i;
-
-	if (nh_grp->count != fi->fib_nhs)
-		return false;
-	for (i = 0; i < nh_grp->count; i++) {
-		struct mlxsw_sp_nexthop *nh = &nh_grp->nexthops[i];
-
-		if (!mlxsw_sp_nexthop_match(nh, fi))
-			return false;
-	}
-	return true;
-}
-
-static struct mlxsw_sp_nexthop_group *
-mlxsw_sp_nexthop_group_find(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
-{
-	struct mlxsw_sp_nexthop_group *nh_grp;
-
-	list_for_each_entry(nh_grp, &mlxsw_sp->router.nexthop_group_list,
-			    list) {
-		if (mlxsw_sp_nexthop_group_match(nh_grp, fi))
-			return nh_grp;
-	}
-	return NULL;
-}
-
 static int mlxsw_sp_nexthop_group_get(struct mlxsw_sp *mlxsw_sp,
 				      struct mlxsw_sp_fib_entry *fib_entry,
 				      struct fib_info *fi)
 {
+	struct mlxsw_sp_nexthop_group_key key;
 	struct mlxsw_sp_nexthop_group *nh_grp;
 
-	nh_grp = mlxsw_sp_nexthop_group_find(mlxsw_sp, fi);
+	key.fi = fi;
+	nh_grp = mlxsw_sp_nexthop_group_lookup(mlxsw_sp, key);
 	if (!nh_grp) {
 		nh_grp = mlxsw_sp_nexthop_group_create(mlxsw_sp, fi);
 		if (IS_ERR(nh_grp))
@@ -1537,6 +1713,72 @@ static void mlxsw_sp_nexthop_group_put(struct mlxsw_sp *mlxsw_sp,
 	mlxsw_sp_nexthop_group_destroy(mlxsw_sp, nh_grp);
 }
 
+static bool
+mlxsw_sp_fib_entry_should_offload(const struct mlxsw_sp_fib_entry *fib_entry)
+{
+	struct mlxsw_sp_nexthop_group *nh_group = fib_entry->nh_group;
+
+	switch (fib_entry->type) {
+	case MLXSW_SP_FIB_ENTRY_TYPE_REMOTE:
+		return !!nh_group->adj_index_valid;
+	case MLXSW_SP_FIB_ENTRY_TYPE_LOCAL:
+		return !!nh_group->nh_rif;
+	default:
+		return false;
+	}
+}
+
+static void mlxsw_sp_fib_entry_offload_set(struct mlxsw_sp_fib_entry *fib_entry)
+{
+	fib_entry->offloaded = true;
+
+	switch (fib_entry->vr->proto) {
+	case MLXSW_SP_L3_PROTO_IPV4:
+		fib_info_offload_inc(fib_entry->nh_group->key.fi);
+		break;
+	case MLXSW_SP_L3_PROTO_IPV6:
+		WARN_ON_ONCE(1);
+	}
+}
+
+static void
+mlxsw_sp_fib_entry_offload_unset(struct mlxsw_sp_fib_entry *fib_entry)
+{
+	switch (fib_entry->vr->proto) {
+	case MLXSW_SP_L3_PROTO_IPV4:
+		fib_info_offload_dec(fib_entry->nh_group->key.fi);
+		break;
+	case MLXSW_SP_L3_PROTO_IPV6:
+		WARN_ON_ONCE(1);
+	}
+
+	fib_entry->offloaded = false;
+}
+
+static void
+mlxsw_sp_fib_entry_offload_refresh(struct mlxsw_sp_fib_entry *fib_entry,
+				   enum mlxsw_reg_ralue_op op, int err)
+{
+	switch (op) {
+	case MLXSW_REG_RALUE_OP_WRITE_DELETE:
+		if (!fib_entry->offloaded)
+			return;
+		return mlxsw_sp_fib_entry_offload_unset(fib_entry);
+	case MLXSW_REG_RALUE_OP_WRITE_WRITE:
+		if (err)
+			return;
+		if (mlxsw_sp_fib_entry_should_offload(fib_entry) &&
+		    !fib_entry->offloaded)
+			mlxsw_sp_fib_entry_offload_set(fib_entry);
+		else if (!mlxsw_sp_fib_entry_should_offload(fib_entry) &&
+			 fib_entry->offloaded)
+			mlxsw_sp_fib_entry_offload_unset(fib_entry);
+		return;
+	default:
+		return;
+	}
+}
+
 static int mlxsw_sp_fib_entry_op4_remote(struct mlxsw_sp *mlxsw_sp,
 					 struct mlxsw_sp_fib_entry *fib_entry,
 					 enum mlxsw_reg_ralue_op op)
@@ -1553,7 +1795,7 @@ static int mlxsw_sp_fib_entry_op4_remote(struct mlxsw_sp *mlxsw_sp,
 	 * with provided ECMP size. Otherwise, setup trap and pass
 	 * traffic to kernel.
 	 */
-	if (fib_entry->nh_group->adj_index_valid) {
+	if (mlxsw_sp_fib_entry_should_offload(fib_entry)) {
 		trap_action = MLXSW_REG_RALUE_TRAP_ACTION_NOP;
 		adjacency_index = fib_entry->nh_group->adj_index;
 		ecmp_size = fib_entry->nh_group->ecmp_size;
@@ -1574,16 +1816,26 @@ static int mlxsw_sp_fib_entry_op4_local(struct mlxsw_sp *mlxsw_sp,
 					struct mlxsw_sp_fib_entry *fib_entry,
 					enum mlxsw_reg_ralue_op op)
 {
+	struct mlxsw_sp_rif *r = fib_entry->nh_group->nh_rif;
+	enum mlxsw_reg_ralue_trap_action trap_action;
 	char ralue_pl[MLXSW_REG_RALUE_LEN];
 	u32 *p_dip = (u32 *) fib_entry->key.addr;
 	struct mlxsw_sp_vr *vr = fib_entry->vr;
+	u16 trap_id = 0;
+	u16 rif = 0;
+
+	if (mlxsw_sp_fib_entry_should_offload(fib_entry)) {
+		trap_action = MLXSW_REG_RALUE_TRAP_ACTION_NOP;
+		rif = r->rif;
+	} else {
+		trap_action = MLXSW_REG_RALUE_TRAP_ACTION_TRAP;
+		trap_id = MLXSW_TRAP_ID_RTR_INGRESS0;
+	}
 
 	mlxsw_reg_ralue_pack4(ralue_pl,
 			      (enum mlxsw_reg_ralxx_protocol) vr->proto, op,
 			      vr->id, fib_entry->key.prefix_len, *p_dip);
-	mlxsw_reg_ralue_act_local_pack(ralue_pl,
-				       MLXSW_REG_RALUE_TRAP_ACTION_NOP, 0,
-				       fib_entry->rif);
+	mlxsw_reg_ralue_act_local_pack(ralue_pl, trap_action, trap_id, rif);
 	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ralue), ralue_pl);
 }
 
@@ -1621,13 +1873,17 @@ static int mlxsw_sp_fib_entry_op(struct mlxsw_sp *mlxsw_sp,
 				 struct mlxsw_sp_fib_entry *fib_entry,
 				 enum mlxsw_reg_ralue_op op)
 {
+	int err = -EINVAL;
+
 	switch (fib_entry->vr->proto) {
 	case MLXSW_SP_L3_PROTO_IPV4:
-		return mlxsw_sp_fib_entry_op4(mlxsw_sp, fib_entry, op);
+		err = mlxsw_sp_fib_entry_op4(mlxsw_sp, fib_entry, op);
+		break;
 	case MLXSW_SP_L3_PROTO_IPV6:
-		return -EINVAL;
+		return err;
 	}
-	return -EINVAL;
+	mlxsw_sp_fib_entry_offload_refresh(fib_entry, op, err);
+	return err;
 }
 
 static int mlxsw_sp_fib_entry_update(struct mlxsw_sp *mlxsw_sp,
@@ -1645,14 +1901,11 @@ static int mlxsw_sp_fib_entry_del(struct mlxsw_sp *mlxsw_sp,
 }
 
 static int
-mlxsw_sp_router_fib4_entry_init(struct mlxsw_sp *mlxsw_sp,
-				const struct fib_entry_notifier_info *fen_info,
-				struct mlxsw_sp_fib_entry *fib_entry)
+mlxsw_sp_fib4_entry_type_set(struct mlxsw_sp *mlxsw_sp,
+			     const struct fib_entry_notifier_info *fen_info,
+			     struct mlxsw_sp_fib_entry *fib_entry)
 {
 	struct fib_info *fi = fen_info->fi;
-	struct mlxsw_sp_rif *r = NULL;
-	int nhsel;
-	int err;
 
 	if (fen_info->type == RTN_LOCAL || fen_info->type == RTN_BROADCAST) {
 		fib_entry->type = MLXSW_SP_FIB_ENTRY_TYPE_TRAP;
@@ -1660,52 +1913,13 @@ mlxsw_sp_router_fib4_entry_init(struct mlxsw_sp *mlxsw_sp,
 	}
 	if (fen_info->type != RTN_UNICAST)
 		return -EINVAL;
-
-	for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
-		const struct fib_nh *nh = &fi->fib_nh[nhsel];
-
-		if (!nh->nh_dev)
-			continue;
-		r = mlxsw_sp_rif_find_by_dev(mlxsw_sp, nh->nh_dev);
-		if (!r) {
-			/* In case router interface is not found for
-			 * at least one of the nexthops, that means
-			 * the nexthop points to some device unrelated
-			 * to us. Set trap and pass the packets for
-			 * this prefix to kernel.
-			 */
-			break;
-		}
-	}
-
-	if (!r) {
-		fib_entry->type = MLXSW_SP_FIB_ENTRY_TYPE_TRAP;
-		return 0;
-	}
-
-	if (fi->fib_scope != RT_SCOPE_UNIVERSE) {
+	if (fi->fib_nh->nh_scope != RT_SCOPE_LINK)
 		fib_entry->type = MLXSW_SP_FIB_ENTRY_TYPE_LOCAL;
-		fib_entry->rif = r->rif;
-	} else {
+	else
 		fib_entry->type = MLXSW_SP_FIB_ENTRY_TYPE_REMOTE;
-		err = mlxsw_sp_nexthop_group_get(mlxsw_sp, fib_entry, fi);
-		if (err)
-			return err;
-	}
-	fib_info_offload_inc(fen_info->fi);
 	return 0;
 }
 
-static void
-mlxsw_sp_router_fib4_entry_fini(struct mlxsw_sp *mlxsw_sp,
-				struct mlxsw_sp_fib_entry *fib_entry)
-{
-	if (fib_entry->type != MLXSW_SP_FIB_ENTRY_TYPE_TRAP)
-		fib_info_offload_dec(fib_entry->fi);
-	if (fib_entry->type == MLXSW_SP_FIB_ENTRY_TYPE_REMOTE)
-		mlxsw_sp_nexthop_group_put(mlxsw_sp, fib_entry);
-}
-
 static struct mlxsw_sp_fib_entry *
 mlxsw_sp_fib_entry_get(struct mlxsw_sp *mlxsw_sp,
 		       const struct fib_entry_notifier_info *fen_info)
@@ -1736,16 +1950,20 @@ mlxsw_sp_fib_entry_get(struct mlxsw_sp *mlxsw_sp,
 		goto err_fib_entry_create;
 	}
 	fib_entry->vr = vr;
-	fib_entry->fi = fi;
 	fib_entry->ref_count = 1;
 
-	err = mlxsw_sp_router_fib4_entry_init(mlxsw_sp, fen_info, fib_entry);
+	err = mlxsw_sp_fib4_entry_type_set(mlxsw_sp, fen_info, fib_entry);
 	if (err)
-		goto err_fib4_entry_init;
+		goto err_fib4_entry_type_set;
+
+	err = mlxsw_sp_nexthop_group_get(mlxsw_sp, fib_entry, fi);
+	if (err)
+		goto err_nexthop_group_get;
 
 	return fib_entry;
 
-err_fib4_entry_init:
+err_nexthop_group_get:
+err_fib4_entry_type_set:
 	mlxsw_sp_fib_entry_destroy(fib_entry);
 err_fib_entry_create:
 	mlxsw_sp_vr_put(mlxsw_sp, vr);
@@ -1776,7 +1994,7 @@ static void mlxsw_sp_fib_entry_put(struct mlxsw_sp *mlxsw_sp,
 	struct mlxsw_sp_vr *vr = fib_entry->vr;
 
 	if (--fib_entry->ref_count == 0) {
-		mlxsw_sp_router_fib4_entry_fini(mlxsw_sp, fib_entry);
+		mlxsw_sp_nexthop_group_put(mlxsw_sp, fib_entry);
 		mlxsw_sp_fib_entry_destroy(fib_entry);
 	}
 	mlxsw_sp_vr_put(mlxsw_sp, vr);
@@ -1922,6 +2140,28 @@ static void mlxsw_sp_router_fib4_abort(struct mlxsw_sp *mlxsw_sp)
 		dev_warn(mlxsw_sp->bus_info->dev, "Failed to set abort trap.\n");
 }
 
+static int mlxsw_sp_router_rif_disable(struct mlxsw_sp *mlxsw_sp, u16 rif)
+{
+	char ritr_pl[MLXSW_REG_RITR_LEN];
+	int err;
+
+	mlxsw_reg_ritr_rif_pack(ritr_pl, rif);
+	err = mlxsw_reg_query(mlxsw_sp->core, MLXSW_REG(ritr), ritr_pl);
+	if (WARN_ON_ONCE(err))
+		return err;
+
+	mlxsw_reg_ritr_enable_set(ritr_pl, false);
+	return mlxsw_reg_write(mlxsw_sp->core, MLXSW_REG(ritr), ritr_pl);
+}
+
+void mlxsw_sp_router_rif_gone_sync(struct mlxsw_sp *mlxsw_sp,
+				   struct mlxsw_sp_rif *r)
+{
+	mlxsw_sp_router_rif_disable(mlxsw_sp, r->rif);
+	mlxsw_sp_nexthop_rif_gone_sync(mlxsw_sp, r);
+	mlxsw_sp_neigh_rif_gone_sync(mlxsw_sp, r);
+}
+
 static int __mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp)
 {
 	char rgcr_pl[MLXSW_REG_RGCR_LEN];
@@ -1966,7 +2206,10 @@ static void __mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp)
 
 struct mlxsw_sp_fib_event_work {
 	struct work_struct work;
-	struct fib_entry_notifier_info fen_info;
+	union {
+		struct fib_entry_notifier_info fen_info;
+		struct fib_nh_notifier_info fnh_info;
+	};
 	struct mlxsw_sp *mlxsw_sp;
 	unsigned long event;
 };
@@ -1995,6 +2238,12 @@ static void mlxsw_sp_router_fib_event_work(struct work_struct *work)
 	case FIB_EVENT_RULE_DEL:
 		mlxsw_sp_router_fib4_abort(mlxsw_sp);
 		break;
+	case FIB_EVENT_NH_ADD: /* fall through */
+	case FIB_EVENT_NH_DEL:
+		mlxsw_sp_nexthop_event(mlxsw_sp, fib_work->event,
+				       fib_work->fnh_info.fib_nh);
+		fib_info_put(fib_work->fnh_info.fib_nh->nh_parent);
+		break;
 	}
 	rtnl_unlock();
 	kfree(fib_work);
@@ -2028,6 +2277,11 @@ static int mlxsw_sp_router_fib_event(struct notifier_block *nb,
 		 */
 		fib_info_hold(fib_work->fen_info.fi);
 		break;
+	case FIB_EVENT_NH_ADD: /* fall through */
+	case FIB_EVENT_NH_DEL:
+		memcpy(&fib_work->fnh_info, ptr, sizeof(fib_work->fnh_info));
+		fib_info_hold(fib_work->fnh_info.fib_nh->nh_parent);
+		break;
 	}
 
 	mlxsw_core_schedule_work(&fib_work->work);
@@ -2052,11 +2306,20 @@ int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp)
 	int err;
 
 	INIT_LIST_HEAD(&mlxsw_sp->router.nexthop_neighs_list);
-	INIT_LIST_HEAD(&mlxsw_sp->router.nexthop_group_list);
 	err = __mlxsw_sp_router_init(mlxsw_sp);
 	if (err)
 		return err;
 
+	err = rhashtable_init(&mlxsw_sp->router.nexthop_ht,
+			      &mlxsw_sp_nexthop_ht_params);
+	if (err)
+		goto err_nexthop_ht_init;
+
+	err = rhashtable_init(&mlxsw_sp->router.nexthop_group_ht,
+			      &mlxsw_sp_nexthop_group_ht_params);
+	if (err)
+		goto err_nexthop_group_ht_init;
+
 	mlxsw_sp_lpm_init(mlxsw_sp);
 	err = mlxsw_sp_vrs_init(mlxsw_sp);
 	if (err)
@@ -2079,6 +2342,10 @@ int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp)
 err_neigh_init:
 	mlxsw_sp_vrs_fini(mlxsw_sp);
 err_vrs_init:
+	rhashtable_destroy(&mlxsw_sp->router.nexthop_group_ht);
+err_nexthop_group_ht_init:
+	rhashtable_destroy(&mlxsw_sp->router.nexthop_ht);
+err_nexthop_ht_init:
 	__mlxsw_sp_router_fini(mlxsw_sp);
 	return err;
 }
@@ -2088,5 +2355,7 @@ void mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp)
 	unregister_fib_notifier(&mlxsw_sp->fib_nb);
 	mlxsw_sp_neigh_fini(mlxsw_sp);
 	mlxsw_sp_vrs_fini(mlxsw_sp);
+	rhashtable_destroy(&mlxsw_sp->router.nexthop_group_ht);
+	rhashtable_destroy(&mlxsw_sp->router.nexthop_ht);
 	__mlxsw_sp_router_fini(mlxsw_sp);
 }

include/net/ip_fib.h

@@ -214,11 +214,18 @@ struct fib_entry_notifier_info {
 	u32 nlflags;
 };
 
+struct fib_nh_notifier_info {
+	struct fib_notifier_info info; /* must be first */
+	struct fib_nh *fib_nh;
+};
+
 enum fib_event_type {
 	FIB_EVENT_ENTRY_ADD,
 	FIB_EVENT_ENTRY_DEL,
 	FIB_EVENT_RULE_ADD,
 	FIB_EVENT_RULE_DEL,
+	FIB_EVENT_NH_ADD,
+	FIB_EVENT_NH_DEL,
 };
 
 int register_fib_notifier(struct notifier_block *nb,

net/ipv4/fib_semantics.c

@@ -1355,6 +1355,36 @@ int fib_sync_down_addr(struct net_device *dev, __be32 local)
 	return ret;
 }
 
+static int call_fib_nh_notifiers(struct fib_nh *fib_nh,
+				 enum fib_event_type event_type)
+{
+	struct in_device *in_dev = __in_dev_get_rtnl(fib_nh->nh_dev);
+	struct fib_nh_notifier_info info = {
+		.fib_nh = fib_nh,
+	};
+
+	switch (event_type) {
+	case FIB_EVENT_NH_ADD:
+		if (fib_nh->nh_flags & RTNH_F_DEAD)
+			break;
+		if (IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
+		    fib_nh->nh_flags & RTNH_F_LINKDOWN)
+			break;
+		return call_fib_notifiers(dev_net(fib_nh->nh_dev), event_type,
+					  &info.info);
+	case FIB_EVENT_NH_DEL:
+		if ((IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
+		     fib_nh->nh_flags & RTNH_F_LINKDOWN) ||
+		    (fib_nh->nh_flags & RTNH_F_DEAD))
+			return call_fib_notifiers(dev_net(fib_nh->nh_dev),
+						  event_type, &info.info);
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
 /* Event              force Flags           Description
  * NETDEV_CHANGE      0     LINKDOWN        Carrier OFF, not for scope host
  * NETDEV_DOWN        0     LINKDOWN|DEAD   Link down, not for scope host
@@ -1396,6 +1426,8 @@ int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force)
 					nexthop_nh->nh_flags |= RTNH_F_LINKDOWN;
 					break;
 				}
+				call_fib_nh_notifiers(nexthop_nh,
+						      FIB_EVENT_NH_DEL);
 				dead++;
 			}
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
@@ -1550,6 +1582,7 @@ int fib_sync_up(struct net_device *dev, unsigned int nh_flags)
 				continue;
 			alive++;
 			nexthop_nh->nh_flags &= ~nh_flags;
+			call_fib_nh_notifiers(nexthop_nh, FIB_EVENT_NH_ADD);
 		} endfor_nexthops(fi)
 
 		if (alive > 0) {