Move forward and use new PRESTERA_FIB_TYPE_UC_NH to provide basic
nexthop routes support.
Provide deinitialization sequence for all created router objects.

Limitations:
- Only "local" and "main" tables supported
- Only generic interfaces supported for router (no bridges or vlans)

Co-developed-by: Taras Chornyi <redacted>
Signed-off-by: Taras Chornyi <redacted>
Co-developed-by: Oleksandr Mazur <redacted>
Signed-off-by: Oleksandr Mazur <redacted>
Signed-off-by: Yevhen Orlov <redacted>
---
 .../net/ethernet/marvell/prestera/prestera.h  |   1 +
 .../marvell/prestera/prestera_router.c        | 815 +++++++++++++++++-
 2 files changed, 813 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/marvell/prestera/prestera.h b/drivers/net/ethernet/marvell/prestera/prestera.h
index 2f2f80e7e358..540a36069b79 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera.h

@@ -316,6 +316,7 @@ struct prestera_router {
 	struct rhashtable nh_neigh_ht;
 	struct rhashtable nexthop_group_ht;
 	struct rhashtable fib_ht;
+	struct rhashtable kern_neigh_cache_ht;
 	struct rhashtable kern_fib_cache_ht;
 	struct notifier_block inetaddr_nb;
 	struct notifier_block inetaddr_valid_nb;

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_router.c b/drivers/net/ethernet/marvell/prestera/prestera_router.c
index a6af3b53838e..771d123345ac 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_router.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_router.c

@@ -8,11 +8,30 @@
 #include <net/switchdev.h>
 #include <linux/rhashtable.h>
 #include <net/nexthop.h>
+#include <net/arp.h>
+#include <linux/if_vlan.h>
+#include <linux/if_macvlan.h>
 #include <net/netevent.h>
 
 #include "prestera.h"
 #include "prestera_router_hw.h"
 
+struct prestera_kern_neigh_cache_key {
+	struct prestera_ip_addr addr;
+	struct net_device *dev;
+};
+
+struct prestera_kern_neigh_cache {
+	struct prestera_kern_neigh_cache_key key;
+	struct rhash_head ht_node;
+	struct list_head kern_fib_cache_list;
+	/* Hold prepared nh_neigh info if is in_kernel */
+	struct prestera_neigh_info nh_neigh_info;
+	/* Indicate if neighbour is reachable by direct route */
+	bool reachable;
+	/* Lock cache if neigh is present in kernel */
+	bool in_kernel;
+};
 struct prestera_kern_fib_cache_key {
 	struct prestera_ip_addr addr;
 	u32 prefix_len;

@@ -25,9 +44,15 @@ struct prestera_kern_fib_cache {
 	struct {
 		struct prestera_fib_key fib_key;
 		enum prestera_fib_type fib_type;
+		struct prestera_nexthop_group_key nh_grp_key;
 	} lpm_info; /* hold prepared lpm info */
 	/* Indicate if route is not overlapped by another table */
 	struct rhash_head ht_node; /* node of prestera_router */
+	struct prestera_kern_neigh_cache_head {
+		struct prestera_kern_fib_cache *this;
+		struct list_head head;
+		struct prestera_kern_neigh_cache *n_cache;
+	} kern_neigh_cache_head[PRESTERA_NHGR_SIZE_MAX];
 	union {
 		struct fib_notifier_info info; /* point to any of 4/6 */
 		struct fib_entry_notifier_info fen4_info;

@@ -35,6 +60,13 @@ struct prestera_kern_fib_cache {
 	bool reachable;
 };
 
+static const struct rhashtable_params __prestera_kern_neigh_cache_ht_params = {
+	.key_offset  = offsetof(struct prestera_kern_neigh_cache, key),
+	.head_offset = offsetof(struct prestera_kern_neigh_cache, ht_node),
+	.key_len     = sizeof(struct prestera_kern_neigh_cache_key),
+	.automatic_shrinking = true,
+};
+
 static const struct rhashtable_params __prestera_kern_fib_cache_ht_params = {
 	.key_offset  = offsetof(struct prestera_kern_fib_cache, key),
 	.head_offset = offsetof(struct prestera_kern_fib_cache, ht_node),

@@ -67,6 +99,278 @@ prestera_util_fen_info2fib_cache_key(struct fib_notifier_info *info,
 	key->kern_tb_id = fen_info->tb_id;
 }
 
+static int prestera_util_nhc2nc_key(struct prestera_switch *sw,
+				    struct fib_nh_common *nhc,
+				    struct prestera_kern_neigh_cache_key *nk)
+{
+	memset(nk, 0, sizeof(*nk));
+	if (nhc->nhc_gw_family == AF_INET) {
+		nk->addr.v = PRESTERA_IPV4;
+		nk->addr.u.ipv4 = nhc->nhc_gw.ipv4;
+	} else {
+		nk->addr.v = PRESTERA_IPV6;
+		nk->addr.u.ipv6 = nhc->nhc_gw.ipv6;
+	}
+
+	nk->dev = nhc->nhc_dev;
+	return 0;
+}
+
+static void
+prestera_util_nc_key2nh_key(struct prestera_kern_neigh_cache_key *ck,
+			    struct prestera_nh_neigh_key *nk)
+{
+	memset(nk, 0, sizeof(*nk));
+	nk->addr = ck->addr;
+	nk->rif = (void *)ck->dev;
+}
+
+static bool
+prestera_util_nhc_eq_n_cache_key(struct prestera_switch *sw,
+				 struct fib_nh_common *nhc,
+				 struct prestera_kern_neigh_cache_key *nk)
+{
+	struct prestera_kern_neigh_cache_key tk;
+	int err;
+
+	err = prestera_util_nhc2nc_key(sw, nhc, &tk);
+	if (err)
+		return false;
+
+	if (memcmp(&tk, nk, sizeof(tk)))
+		return false;
+
+	return true;
+}
+
+static int
+prestera_util_neigh2nc_key(struct prestera_switch *sw, struct neighbour *n,
+			   struct prestera_kern_neigh_cache_key *key)
+{
+	memset(key, 0, sizeof(*key));
+	if (n->tbl->family == AF_INET) {
+		key->addr.v = PRESTERA_IPV4;
+		key->addr.u.ipv4 = *(__be32 *)n->primary_key;
+	} else {
+		return -ENOENT;
+	}
+
+	key->dev = n->dev;
+
+	return 0;
+}
+
+static bool __prestera_fi_is_direct(struct fib_info *fi)
+{
+	struct fib_nh *fib_nh;
+
+	if (fib_info_num_path(fi) == 1) {
+		fib_nh = fib_info_nh(fi, 0);
+		if (fib_nh->fib_nh_gw_family == AF_UNSPEC)
+			return true;
+	}
+
+	return false;
+}
+
+static bool prestera_fi_is_direct(struct fib_info *fi)
+{
+	if (fi->fib_type != RTN_UNICAST)
+		return false;
+
+	return __prestera_fi_is_direct(fi);
+}
+
+static bool prestera_fi_is_nh(struct fib_info *fi)
+{
+	if (fi->fib_type != RTN_UNICAST)
+		return false;
+
+	return !__prestera_fi_is_direct(fi);
+}
+
+static bool __prestera_fi6_is_direct(struct fib6_info *fi)
+{
+	if (!fi->fib6_nh->nh_common.nhc_gw_family)
+		return true;
+
+	return false;
+}
+
+static bool prestera_fi6_is_direct(struct fib6_info *fi)
+{
+	if (fi->fib6_type != RTN_UNICAST)
+		return false;
+
+	return __prestera_fi6_is_direct(fi);
+}
+
+static bool prestera_fi6_is_nh(struct fib6_info *fi)
+{
+	if (fi->fib6_type != RTN_UNICAST)
+		return false;
+
+	return !__prestera_fi6_is_direct(fi);
+}
+
+static bool prestera_fib_info_is_direct(struct fib_notifier_info *info)
+{
+	struct fib6_entry_notifier_info *fen6_info =
+		container_of(info, struct fib6_entry_notifier_info, info);
+	struct fib_entry_notifier_info *fen_info =
+		container_of(info, struct fib_entry_notifier_info, info);
+
+	if (info->family == AF_INET)
+		return prestera_fi_is_direct(fen_info->fi);
+	else
+		return prestera_fi6_is_direct(fen6_info->rt);
+}
+
+static bool prestera_fib_info_is_nh(struct fib_notifier_info *info)
+{
+	struct fib6_entry_notifier_info *fen6_info =
+		container_of(info, struct fib6_entry_notifier_info, info);
+	struct fib_entry_notifier_info *fen_info =
+		container_of(info, struct fib_entry_notifier_info, info);
+
+	if (info->family == AF_INET)
+		return prestera_fi_is_nh(fen_info->fi);
+	else
+		return prestera_fi6_is_nh(fen6_info->rt);
+}
+
+/* must be called with rcu_read_lock() */
+static int prestera_util_kern_get_route(struct fib_result *res, u32 tb_id,
+					__be32 *addr)
+{
+	struct fib_table *tb;
+	struct flowi4 fl4;
+	int ret;
+
+	/* TODO: walkthrough appropriate tables in kernel
+	 * to know if the same prefix exists in several tables
+	 */
+	tb = fib_new_table(&init_net, tb_id);
+	if (!tb)
+		return -ENOENT;
+
+	memset(&fl4, 0, sizeof(fl4));
+	fl4.daddr = *addr;
+	ret = fib_table_lookup(tb, &fl4, res, FIB_LOOKUP_NOREF);
+	if (ret)
+		return ret;