net: marvell: prestera: Add router nexthops ABI

- Add functions to allocate/delete/set nexthop group
  - NOTE: non-ECMP nexthop is nexthop group with allocated size = 1
- Add function to read state of HW nh (if packets going through it)

Co-developed-by: Taras Chornyi <tchornyi@marvell.com>
Signed-off-by: Taras Chornyi <tchornyi@marvell.com>
Co-developed-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Oleksandr Mazur <oleksandr.mazur@plvision.eu>
Signed-off-by: Yevhen Orlov <yevhen.orlov@plvision.eu>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 349 insertions, 5 deletions

diff --git a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
index 5b0cf3be9a9e..db9d2e9d9904 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_router_hw.c
@@ -8,10 +8,16 @@
 #include "prestera_router_hw.h"
 #include "prestera_acl.h"
 
-/*            +--+
- *   +------->|vr|<-+
- *   |        +--+  |
- *   |              |
+/*                                Nexthop is pointed
+ *                                to port (not rif)
+ *                                +-------+
+ *                              +>|nexthop|
+ *                              | +-------+
+ *                              |
+ *            +--+        +-----++
+ *   +------->|vr|<-+   +>|nh_grp|
+ *   |        +--+  |   | +------+
+ *   |              |   |
  * +-+-------+   +--+---+-+
  * |rif_entry|   |fib_node|
  * +---------+   +--------+
@@ -23,6 +29,8 @@
 
 #define PRESTERA_NHGR_UNUSED (0)
 #define PRESTERA_NHGR_DROP (0xFFFFFFFF)
+/* Need to merge it with router_manager */
+#define PRESTERA_NH_ACTIVE_JIFFER_FILTER 3000 /* ms */
 
 static const struct rhashtable_params __prestera_fib_ht_params = {
 	.key_offset  = offsetof(struct prestera_fib_node, key),
@@ -31,10 +39,44 @@ static const struct rhashtable_params __prestera_fib_ht_params = {
 	.automatic_shrinking = true,
 };
 
+static const struct rhashtable_params __prestera_nh_neigh_ht_params = {
+	.key_offset  = offsetof(struct prestera_nh_neigh, key),
+	.key_len     = sizeof(struct prestera_nh_neigh_key),
+	.head_offset = offsetof(struct prestera_nh_neigh, ht_node),
+};
+
+static const struct rhashtable_params __prestera_nexthop_group_ht_params = {
+	.key_offset  = offsetof(struct prestera_nexthop_group, key),
+	.key_len     = sizeof(struct prestera_nexthop_group_key),
+	.head_offset = offsetof(struct prestera_nexthop_group, ht_node),
+};
+
+static int prestera_nexthop_group_set(struct prestera_switch *sw,
+				      struct prestera_nexthop_group *nh_grp);
+static bool
+prestera_nexthop_group_util_hw_state(struct prestera_switch *sw,
+				     struct prestera_nexthop_group *nh_grp);
+
+/* TODO: move to router.h as macros */
+static bool prestera_nh_neigh_key_is_valid(struct prestera_nh_neigh_key *key)
+{
+	return memchr_inv(key, 0, sizeof(*key)) ? true : false;
+}
+
 int prestera_router_hw_init(struct prestera_switch *sw)
 {
 	int err;
 
+	err = rhashtable_init(&sw->router->nh_neigh_ht,
+			      &__prestera_nh_neigh_ht_params);
+	if (err)
+		goto err_nh_neigh_ht_init;
+
+	err = rhashtable_init(&sw->router->nexthop_group_ht,
+			      &__prestera_nexthop_group_ht_params);
+	if (err)
+		goto err_nexthop_grp_ht_init;
+
 	err = rhashtable_init(&sw->router->fib_ht,
 			      &__prestera_fib_ht_params);
 	if (err)
@@ -43,7 +85,13 @@ int prestera_router_hw_init(struct prestera_switch *sw)
 	INIT_LIST_HEAD(&sw->router->vr_list);
 	INIT_LIST_HEAD(&sw->router->rif_entry_list);
 
+	return 0;
+
 err_fib_ht_init:
+	rhashtable_destroy(&sw->router->nexthop_group_ht);
+err_nexthop_grp_ht_init:
+	rhashtable_destroy(&sw->router->nh_neigh_ht);
+err_nh_neigh_ht_init:
 	return 0;
 }
 
@@ -52,6 +100,8 @@ void prestera_router_hw_fini(struct prestera_switch *sw)
 	WARN_ON(!list_empty(&sw->router->vr_list));
 	WARN_ON(!list_empty(&sw->router->rif_entry_list));
 	rhashtable_destroy(&sw->router->fib_ht);
+	rhashtable_destroy(&sw->router->nexthop_group_ht);
+	rhashtable_destroy(&sw->router->nh_neigh_ht);
 }
 
 static struct prestera_vr *__prestera_vr_find(struct prestera_switch *sw,
@@ -232,6 +282,286 @@ err_kzalloc:
 	return NULL;
 }
 
+static void __prestera_nh_neigh_destroy(struct prestera_switch *sw,
+					struct prestera_nh_neigh *neigh)
+{
+	rhashtable_remove_fast(&sw->router->nh_neigh_ht,
+			       &neigh->ht_node,
+			       __prestera_nh_neigh_ht_params);
+	kfree(neigh);
+}
+
+static struct prestera_nh_neigh *
+__prestera_nh_neigh_create(struct prestera_switch *sw,
+			   struct prestera_nh_neigh_key *key)
+{
+	struct prestera_nh_neigh *neigh;
+	int err;
+
+	neigh = kzalloc(sizeof(*neigh), GFP_KERNEL);
+	if (!neigh)
+		goto err_kzalloc;
+
+	memcpy(&neigh->key, key, sizeof(*key));
+	neigh->info.connected = false;
+	INIT_LIST_HEAD(&neigh->nexthop_group_list);
+	err = rhashtable_insert_fast(&sw->router->nh_neigh_ht,
+				     &neigh->ht_node,
+				     __prestera_nh_neigh_ht_params);
+	if (err)
+		goto err_rhashtable_insert;
+
+	return neigh;
+
+err_rhashtable_insert:
+	kfree(neigh);
+err_kzalloc:
+	return NULL;
+}
+
+struct prestera_nh_neigh *
+prestera_nh_neigh_find(struct prestera_switch *sw,
+		       struct prestera_nh_neigh_key *key)
+{
+	struct prestera_nh_neigh *nh_neigh;
+
+	nh_neigh = rhashtable_lookup_fast(&sw->router->nh_neigh_ht,
+					  key, __prestera_nh_neigh_ht_params);
+	return IS_ERR(nh_neigh) ? NULL : nh_neigh;
+}
+
+struct prestera_nh_neigh *
+prestera_nh_neigh_get(struct prestera_switch *sw,
+		      struct prestera_nh_neigh_key *key)
+{
+	struct prestera_nh_neigh *neigh;
+
+	neigh = prestera_nh_neigh_find(sw, key);
+	if (!neigh)
+		return __prestera_nh_neigh_create(sw, key);
+
+	return neigh;
+}
+
+void prestera_nh_neigh_put(struct prestera_switch *sw,
+			   struct prestera_nh_neigh *neigh)
+{
+	if (list_empty(&neigh->nexthop_group_list))
+		__prestera_nh_neigh_destroy(sw, neigh);
+}
+
+/* Updates new prestera_neigh_info */
+int prestera_nh_neigh_set(struct prestera_switch *sw,
+			  struct prestera_nh_neigh *neigh)
+{
+	struct prestera_nh_neigh_head *nh_head;
+	struct prestera_nexthop_group *nh_grp;
+	int err;
+
+	list_for_each_entry(nh_head, &neigh->nexthop_group_list, head) {
+		nh_grp = nh_head->this;
+		err = prestera_nexthop_group_set(sw, nh_grp);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+bool prestera_nh_neigh_util_hw_state(struct prestera_switch *sw,
+				     struct prestera_nh_neigh *nh_neigh)
+{
+	bool state;
+	struct prestera_nh_neigh_head *nh_head, *tmp;
+
+	state = false;
+	list_for_each_entry_safe(nh_head, tmp,
+				 &nh_neigh->nexthop_group_list, head) {
+		state = prestera_nexthop_group_util_hw_state(sw, nh_head->this);
+		if (state)
+			goto out;
+	}
+
+out:
+	return state;
+}
+
+static struct prestera_nexthop_group *
+__prestera_nexthop_group_create(struct prestera_switch *sw,
+				struct prestera_nexthop_group_key *key)
+{
+	struct prestera_nexthop_group *nh_grp;
+	struct prestera_nh_neigh *nh_neigh;
+	int nh_cnt, err, gid;
+
+	nh_grp = kzalloc(sizeof(*nh_grp), GFP_KERNEL);
+	if (!nh_grp)
+		goto err_kzalloc;
+
+	memcpy(&nh_grp->key, key, sizeof(*key));
+	for (nh_cnt = 0; nh_cnt < PRESTERA_NHGR_SIZE_MAX; nh_cnt++) {
+		if (!prestera_nh_neigh_key_is_valid(&nh_grp->key.neigh[nh_cnt]))
+			break;
+
+		nh_neigh = prestera_nh_neigh_get(sw,
+						 &nh_grp->key.neigh[nh_cnt]);
+		if (!nh_neigh)
+			goto err_nh_neigh_get;
+
+		nh_grp->nh_neigh_head[nh_cnt].neigh = nh_neigh;
+		nh_grp->nh_neigh_head[nh_cnt].this = nh_grp;
+		list_add(&nh_grp->nh_neigh_head[nh_cnt].head,
+			 &nh_neigh->nexthop_group_list);
+	}
+
+	err = prestera_hw_nh_group_create(sw, nh_cnt, &nh_grp->grp_id);
+	if (err)
+		goto err_nh_group_create;
+
+	err = prestera_nexthop_group_set(sw, nh_grp);
+	if (err)
+		goto err_nexthop_group_set;
+
+	err = rhashtable_insert_fast(&sw->router->nexthop_group_ht,
+				     &nh_grp->ht_node,
+				     __prestera_nexthop_group_ht_params);
+	if (err)
+		goto err_ht_insert;
+
+	/* reset cache for created group */
+	gid = nh_grp->grp_id;
+	sw->router->nhgrp_hw_state_cache[gid / 8] &= ~BIT(gid % 8);
+
+	return nh_grp;
+
+err_ht_insert:
+err_nexthop_group_set:
+	prestera_hw_nh_group_delete(sw, nh_cnt, nh_grp->grp_id);
+err_nh_group_create:
+err_nh_neigh_get:
+	for (nh_cnt--; nh_cnt >= 0; nh_cnt--) {
+		list_del(&nh_grp->nh_neigh_head[nh_cnt].head);
+		prestera_nh_neigh_put(sw, nh_grp->nh_neigh_head[nh_cnt].neigh);
+	}
+
+	kfree(nh_grp);
+err_kzalloc:
+	return NULL;
+}
+
+static void
+__prestera_nexthop_group_destroy(struct prestera_switch *sw,
+				 struct prestera_nexthop_group *nh_grp)
+{
+	struct prestera_nh_neigh *nh_neigh;
+	int nh_cnt;
+
+	rhashtable_remove_fast(&sw->router->nexthop_group_ht,
+			       &nh_grp->ht_node,
+			       __prestera_nexthop_group_ht_params);
+
+	for (nh_cnt = 0; nh_cnt < PRESTERA_NHGR_SIZE_MAX; nh_cnt++) {
+		nh_neigh = nh_grp->nh_neigh_head[nh_cnt].neigh;
+		if (!nh_neigh)
+			break;
+
+		list_del(&nh_grp->nh_neigh_head[nh_cnt].head);
+		prestera_nh_neigh_put(sw, nh_neigh);
+	}
+
+	prestera_hw_nh_group_delete(sw, nh_cnt, nh_grp->grp_id);
+	kfree(nh_grp);
+}
+
+static struct prestera_nexthop_group *
+__prestera_nexthop_group_find(struct prestera_switch *sw,
+			      struct prestera_nexthop_group_key *key)
+{
+	struct prestera_nexthop_group *nh_grp;
+
+	nh_grp = rhashtable_lookup_fast(&sw->router->nexthop_group_ht,
+					key, __prestera_nexthop_group_ht_params);
+	return IS_ERR(nh_grp) ? NULL : nh_grp;
+}
+
+static struct prestera_nexthop_group *
+prestera_nexthop_group_get(struct prestera_switch *sw,
+			   struct prestera_nexthop_group_key *key)
+{
+	struct prestera_nexthop_group *nh_grp;
+
+	nh_grp = __prestera_nexthop_group_find(sw, key);
+	if (nh_grp) {
+		refcount_inc(&nh_grp->refcount);
+	} else {
+		nh_grp = __prestera_nexthop_group_create(sw, key);
+		if (IS_ERR(nh_grp))
+			return ERR_CAST(nh_grp);
+
+		refcount_set(&nh_grp->refcount, 1);
+	}
+
+	return nh_grp;
+}
+
+static void prestera_nexthop_group_put(struct prestera_switch *sw,
+				       struct prestera_nexthop_group *nh_grp)
+{
+	if (refcount_dec_and_test(&nh_grp->refcount))
+		__prestera_nexthop_group_destroy(sw, nh_grp);
+}
+
+/* Updates with new nh_neigh's info */
+static int prestera_nexthop_group_set(struct prestera_switch *sw,
+				      struct prestera_nexthop_group *nh_grp)
+{
+	struct prestera_neigh_info info[PRESTERA_NHGR_SIZE_MAX];
+	struct prestera_nh_neigh *neigh;
+	int nh_cnt;
+
+	memset(&info[0], 0, sizeof(info));
+	for (nh_cnt = 0; nh_cnt < PRESTERA_NHGR_SIZE_MAX; nh_cnt++) {
+		neigh = nh_grp->nh_neigh_head[nh_cnt].neigh;
+		if (!neigh)
+			break;
+
+		memcpy(&info[nh_cnt], &neigh->info, sizeof(neigh->info));
+	}
+
+	return prestera_hw_nh_entries_set(sw, nh_cnt, &info[0], nh_grp->grp_id);
+}
+
+static bool
+prestera_nexthop_group_util_hw_state(struct prestera_switch *sw,
+				     struct prestera_nexthop_group *nh_grp)
+{
+	int err;
+	u32 buf_size = sw->size_tbl_router_nexthop / 8 + 1;
+	u32 gid = nh_grp->grp_id;
+	u8 *cache = sw->router->nhgrp_hw_state_cache;
+
+	/* Antijitter
+	 * Prevent situation, when we read state of nh_grp twice in short time,
+	 * and state bit is still cleared on second call. So just stuck active
+	 * state for PRESTERA_NH_ACTIVE_JIFFER_FILTER, after last occurred.
+	 */
+	if (!time_before(jiffies, sw->router->nhgrp_hw_cache_kick +
+			msecs_to_jiffies(PRESTERA_NH_ACTIVE_JIFFER_FILTER))) {
+		err = prestera_hw_nhgrp_blk_get(sw, cache, buf_size);
+		if (err) {
+			pr_err("Failed to get hw state nh_grp's");
+			return false;
+		}
+
+		sw->router->nhgrp_hw_cache_kick = jiffies;
+	}
+
+	if (cache[gid / 8] & BIT(gid % 8))
+		return true;
+
+	return false;
+}
+
 struct prestera_fib_node *
 prestera_fib_node_find(struct prestera_switch *sw, struct prestera_fib_key *key)
 {
@@ -251,6 +581,9 @@ static void __prestera_fib_node_destruct(struct prestera_switch *sw,
 	prestera_hw_lpm_del(sw, vr->hw_vr_id, fib_node->key.addr.u.ipv4,
 			    fib_node->key.prefix_len);
 	switch (fib_node->info.type) {
+	case PRESTERA_FIB_TYPE_UC_NH:
+		prestera_nexthop_group_put(sw, fib_node->info.nh_grp);
+		break;
 	case PRESTERA_FIB_TYPE_TRAP:
 		break;
 	case PRESTERA_FIB_TYPE_DROP:
@@ -275,7 +608,8 @@ void prestera_fib_node_destroy(struct prestera_switch *sw,
 struct prestera_fib_node *
 prestera_fib_node_create(struct prestera_switch *sw,
 			 struct prestera_fib_key *key,
-			 enum prestera_fib_type fib_type)
+			 enum prestera_fib_type fib_type,
+			 struct prestera_nexthop_group_key *nh_grp_key)
 {
 	struct prestera_fib_node *fib_node;
 	u32 grp_id;
@@ -302,6 +636,14 @@ prestera_fib_node_create(struct prestera_switch *sw,
 	case PRESTERA_FIB_TYPE_DROP:
 		grp_id = PRESTERA_NHGR_DROP;
 		break;
+	case PRESTERA_FIB_TYPE_UC_NH:
+		fib_node->info.nh_grp = prestera_nexthop_group_get(sw,
+								   nh_grp_key);
+		if (!fib_node->info.nh_grp)
+			goto err_nh_grp_get;
+
+		grp_id = fib_node->info.nh_grp->grp_id;
+		break;
 	default:
 		pr_err("Unsupported fib_type %d", fib_type);
 		goto err_nh_grp_get;
@@ -323,6 +665,8 @@ err_ht_insert:
 	prestera_hw_lpm_del(sw, vr->hw_vr_id, key->addr.u.ipv4,
 			    key->prefix_len);
 err_lpm_add:
+	if (fib_type == PRESTERA_FIB_TYPE_UC_NH)
+		prestera_nexthop_group_put(sw, fib_node->info.nh_grp);
 err_nh_grp_get:
 	prestera_vr_put(sw, vr);
 err_vr_get: