mlxsw: spectrum_mr: Convert into using mr_mfc

Current multicast routing logic in driver assumes it's always meant to
deal with IPv4 multicast routes, leaving several placeholders for
later IPv6 support [currently usually WARN()].

This patch changes the driver's internal multicast route struct into
holding a common mr_mfc instead of the IPv4 mfc_cache.
The various placeholders are grouped into 2:
  - Functions that require only the common bits; These remain and the
    restriction for IPv4-only is lifted.
  - Function that require IPv4-specifics - for handling these functions
    we add sets of operations that encapsulate the protocol differences
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -47,6 +47,11 @@ struct mlxsw_sp_mr {
 	/* priv has to be always the last item */
 };
 
+struct mlxsw_sp_mr_vif;
+struct mlxsw_sp_mr_vif_ops {
+	bool (*is_regular)(const struct mlxsw_sp_mr_vif *vif);
+};
+
 struct mlxsw_sp_mr_vif {
 	struct net_device *dev;
 	const struct mlxsw_sp_rif *rif;
@@ -61,6 +66,9 @@ struct mlxsw_sp_mr_vif {
 	 * instance is used as an ingress VIF
 	 */
 	struct list_head route_ivif_list;
+
+	/* Protocol specific operations for a VIF */
+	const struct mlxsw_sp_mr_vif_ops *ops;
 };
 
 struct mlxsw_sp_mr_route_vif_entry {
@@ -70,6 +78,17 @@ struct mlxsw_sp_mr_route_vif_entry {
 	struct mlxsw_sp_mr_route *mr_route;
 };
 
+struct mlxsw_sp_mr_table;
+struct mlxsw_sp_mr_table_ops {
+	bool (*is_route_valid)(const struct mlxsw_sp_mr_table *mr_table,
+			       const struct mr_mfc *mfc);
+	void (*key_create)(struct mlxsw_sp_mr_table *mr_table,
+			   struct mlxsw_sp_mr_route_key *key,
+			   struct mr_mfc *mfc);
+	bool (*is_route_starg)(const struct mlxsw_sp_mr_table *mr_table,
+			       const struct mlxsw_sp_mr_route *mr_route);
+};
+
 struct mlxsw_sp_mr_table {
 	struct list_head node;
 	enum mlxsw_sp_l3proto proto;
@@ -78,6 +97,7 @@ struct mlxsw_sp_mr_table {
 	struct mlxsw_sp_mr_vif vifs[MAXVIFS];
 	struct list_head route_list;
 	struct rhashtable route_ht;
+	const struct mlxsw_sp_mr_table_ops *ops;
 	char catchall_route_priv[0];
 	/* catchall_route_priv has to be always the last item */
 };
@@ -88,7 +108,7 @@ struct mlxsw_sp_mr_route {
 	struct mlxsw_sp_mr_route_key key;
 	enum mlxsw_sp_mr_route_action route_action;
 	u16 min_mtu;
-	struct mfc_cache *mfc4;
+	struct mr_mfc *mfc;
 	void *route_priv;
 	const struct mlxsw_sp_mr_table *mr_table;
 	/* A list of route_vif_entry structs that point to the egress VIFs */
@@ -104,14 +124,9 @@ static const struct rhashtable_params mlxsw_sp_mr_route_ht_params = {
 	.automatic_shrinking = true,
 };
 
-static bool mlxsw_sp_mr_vif_regular(const struct mlxsw_sp_mr_vif *vif)
-{
-	return !(vif->vif_flags & (VIFF_TUNNEL | VIFF_REGISTER));
-}
-
 static bool mlxsw_sp_mr_vif_valid(const struct mlxsw_sp_mr_vif *vif)
 {
-	return mlxsw_sp_mr_vif_regular(vif) && vif->dev && vif->rif;
+	return vif->ops->is_regular(vif) && vif->dev && vif->rif;
 }
 
 static bool mlxsw_sp_mr_vif_exists(const struct mlxsw_sp_mr_vif *vif)
@@ -122,18 +137,9 @@ static bool mlxsw_sp_mr_vif_exists(const struct mlxsw_sp_mr_vif *vif)
 static bool
 mlxsw_sp_mr_route_ivif_in_evifs(const struct mlxsw_sp_mr_route *mr_route)
 {
-	vifi_t ivif;
+	vifi_t ivif = mr_route->mfc->mfc_parent;
 
-	switch (mr_route->mr_table->proto) {
-	case MLXSW_SP_L3_PROTO_IPV4:
-		ivif = mr_route->mfc4->_c.mfc_parent;
-		return mr_route->mfc4->_c.mfc_un.res.ttls[ivif] != 255;
-	case MLXSW_SP_L3_PROTO_IPV6:
-		/* fall through */
-	default:
-		WARN_ON_ONCE(1);
-	}
-	return false;
+	return mr_route->mfc->mfc_un.res.ttls[ivif] != 255;
 }
 
 static int
@@ -149,19 +155,6 @@ mlxsw_sp_mr_route_valid_evifs_num(const struct mlxsw_sp_mr_route *mr_route)
 	return valid_evifs;
 }
 
-static bool mlxsw_sp_mr_route_starg(const struct mlxsw_sp_mr_route *mr_route)
-{
-	switch (mr_route->mr_table->proto) {
-	case MLXSW_SP_L3_PROTO_IPV4:
-		return mr_route->key.source_mask.addr4 == htonl(INADDR_ANY);
-	case MLXSW_SP_L3_PROTO_IPV6:
-		/* fall through */
-	default:
-		WARN_ON_ONCE(1);
-	}
-	return false;
-}
-
 static enum mlxsw_sp_mr_route_action
 mlxsw_sp_mr_route_action(const struct mlxsw_sp_mr_route *mr_route)
 {
@@ -174,7 +167,8 @@ mlxsw_sp_mr_route_action(const struct mlxsw_sp_mr_route *mr_route)
 	/* The kernel does not match a (*,G) route that the ingress interface is
 	 * not one of the egress interfaces, so trap these kind of routes.
 	 */
-	if (mlxsw_sp_mr_route_starg(mr_route) &&
+	if (mr_route->mr_table->ops->is_route_starg(mr_route->mr_table,
+						    mr_route) &&
 	    !mlxsw_sp_mr_route_ivif_in_evifs(mr_route))
 		return MLXSW_SP_MR_ROUTE_ACTION_TRAP;
 
@@ -195,25 +189,11 @@ mlxsw_sp_mr_route_action(const struct mlxsw_sp_mr_route *mr_route)
 static enum mlxsw_sp_mr_route_prio
 mlxsw_sp_mr_route_prio(const struct mlxsw_sp_mr_route *mr_route)
 {
-	return mlxsw_sp_mr_route_starg(mr_route) ?
+	return mr_route->mr_table->ops->is_route_starg(mr_route->mr_table,
+						       mr_route) ?
 		MLXSW_SP_MR_ROUTE_PRIO_STARG : MLXSW_SP_MR_ROUTE_PRIO_SG;
 }
 
-static void mlxsw_sp_mr_route4_key(struct mlxsw_sp_mr_table *mr_table,
-				   struct mlxsw_sp_mr_route_key *key,
-				   const struct mfc_cache *mfc)
-{
-	bool starg = (mfc->mfc_origin == htonl(INADDR_ANY));
-
-	memset(key, 0, sizeof(*key));
-	key->vrid = mr_table->vr_id;
-	key->proto = mr_table->proto;
-	key->group.addr4 = mfc->mfc_mcastgrp;
-	key->group_mask.addr4 = htonl(0xffffffff);
-	key->source.addr4 = mfc->mfc_origin;
-	key->source_mask.addr4 = htonl(starg ? 0 : 0xffffffff);
-}
-
 static int mlxsw_sp_mr_route_evif_link(struct mlxsw_sp_mr_route *mr_route,
 				       struct mlxsw_sp_mr_vif *mr_vif)
 {
@@ -356,12 +336,13 @@ mlxsw_sp_mr_route4_create(struct mlxsw_sp_mr_table *mr_table,
 	if (!mr_route)
 		return ERR_PTR(-ENOMEM);
 	INIT_LIST_HEAD(&mr_route->evif_list);
-	mlxsw_sp_mr_route4_key(mr_table, &mr_route->key, mfc);
 
 	/* Find min_mtu and link iVIF and eVIFs */
 	mr_route->min_mtu = ETH_MAX_MTU;
 	mr_cache_hold(&mfc->_c);
-	mr_route->mfc4 = mfc;
+	mr_route->mfc = &mfc->_c;
+	mr_table->ops->key_create(mr_table, &mr_route->key, mr_route->mfc);
+
 	mr_route->mr_table = mr_table;
 	for (i = 0; i < MAXVIFS; i++) {
 		if (mfc->_c.mfc_un.res.ttls[i] != 255) {
@@ -393,7 +374,7 @@ static void mlxsw_sp_mr_route4_destroy(struct mlxsw_sp_mr_table *mr_table,
 	struct mlxsw_sp_mr_route_vif_entry *rve, *tmp;
 
 	mlxsw_sp_mr_route_ivif_unlink(mr_route);
-	mr_cache_put((struct mr_mfc *)mr_route->mfc4);
+	mr_cache_put((struct mr_mfc *)mr_route->mfc);
 	list_for_each_entry_safe(rve, tmp, &mr_route->evif_list, route_node)
 		mlxsw_sp_mr_route_evif_unlink(rve);
 	kfree(mr_route);
@@ -416,18 +397,10 @@ static void mlxsw_sp_mr_route_destroy(struct mlxsw_sp_mr_table *mr_table,
 static void mlxsw_sp_mr_mfc_offload_set(struct mlxsw_sp_mr_route *mr_route,
 					bool offload)
 {
-	switch (mr_route->mr_table->proto) {
-	case MLXSW_SP_L3_PROTO_IPV4:
 	if (offload)
-			mr_route->mfc4->_c.mfc_flags |= MFC_OFFLOAD;
+		mr_route->mfc->mfc_flags |= MFC_OFFLOAD;
 	else
-			mr_route->mfc4->_c.mfc_flags &= ~MFC_OFFLOAD;
-		break;
-	case MLXSW_SP_L3_PROTO_IPV6:
-		/* fall through */
-	default:
-		WARN_ON_ONCE(1);
-	}
+		mr_route->mfc->mfc_flags &= ~MFC_OFFLOAD;
 }
 
 static void mlxsw_sp_mr_mfc_offload_update(struct mlxsw_sp_mr_route *mr_route)
@@ -456,15 +429,8 @@ int mlxsw_sp_mr_route4_add(struct mlxsw_sp_mr_table *mr_table,
 	struct mlxsw_sp_mr_route *mr_route;
 	int err;
 
-	/* If the route is a (*,*) route, abort, as these kind of routes are
-	 * used for proxy routes.
-	 */
-	if (mfc->mfc_origin == htonl(INADDR_ANY) &&
-	    mfc->mfc_mcastgrp == htonl(INADDR_ANY)) {
-		dev_warn(mr_table->mlxsw_sp->bus_info->dev,
-			 "Offloading proxy routes is not supported.\n");
+	if (!mr_table->ops->is_route_valid(mr_table, &mfc->_c))
 		return -EINVAL;
-	}
 
 	/* Create a new route */
 	mr_route = mlxsw_sp_mr_route4_create(mr_table, mfc);
@@ -535,7 +501,7 @@ void mlxsw_sp_mr_route4_del(struct mlxsw_sp_mr_table *mr_table,
 	struct mlxsw_sp_mr_route *mr_route;
 	struct mlxsw_sp_mr_route_key key;
 
-	mlxsw_sp_mr_route4_key(mr_table, &key, mfc);
+	mr_table->ops->key_create(mr_table, &key, &mfc->_c);
 	mr_route = rhashtable_lookup_fast(&mr_table->route_ht, &key,
 					  mlxsw_sp_mr_route_ht_params);
 	if (mr_route)
@@ -840,6 +806,70 @@ void mlxsw_sp_mr_rif_mtu_update(struct mlxsw_sp_mr_table *mr_table,
 	}
 }
 
+/* Protocol specific functions */
+static bool
+mlxsw_sp_mr_route4_validate(const struct mlxsw_sp_mr_table *mr_table,
+			    const struct mr_mfc *c)
+{
+	struct mfc_cache *mfc = (struct mfc_cache *) c;
+
+	/* If the route is a (*,*) route, abort, as these kind of routes are
+	 * used for proxy routes.
+	 */
+	if (mfc->mfc_origin == htonl(INADDR_ANY) &&
+	    mfc->mfc_mcastgrp == htonl(INADDR_ANY)) {
+		dev_warn(mr_table->mlxsw_sp->bus_info->dev,
+			 "Offloading proxy routes is not supported.\n");
+		return false;
+	}
+	return true;
+}
+
+static void mlxsw_sp_mr_route4_key(struct mlxsw_sp_mr_table *mr_table,
+				   struct mlxsw_sp_mr_route_key *key,
+				   struct mr_mfc *c)
+{
+	const struct mfc_cache *mfc = (struct mfc_cache *) c;
+	bool starg;
+
+	starg = (mfc->mfc_origin == htonl(INADDR_ANY));
+
+	memset(key, 0, sizeof(*key));
+	key->vrid = mr_table->vr_id;
+	key->proto = MLXSW_SP_L3_PROTO_IPV4;
+	key->group.addr4 = mfc->mfc_mcastgrp;
+	key->group_mask.addr4 = htonl(0xffffffff);
+	key->source.addr4 = mfc->mfc_origin;
+	key->source_mask.addr4 = htonl(starg ? 0 : 0xffffffff);
+}
+
+static bool mlxsw_sp_mr_route4_starg(const struct mlxsw_sp_mr_table *mr_table,
+				     const struct mlxsw_sp_mr_route *mr_route)
+{
+	return mr_route->key.source_mask.addr4 == htonl(INADDR_ANY);
+}
+
+static bool mlxsw_sp_mr_vif4_is_regular(const struct mlxsw_sp_mr_vif *vif)
+{
+	return !(vif->vif_flags & (VIFF_TUNNEL | VIFF_REGISTER));
+}
+
+static struct
+mlxsw_sp_mr_vif_ops mlxsw_sp_mr_vif_ops_arr[] = {
+	{
+		.is_regular = mlxsw_sp_mr_vif4_is_regular,
+	},
+};
+
+static struct
+mlxsw_sp_mr_table_ops mlxsw_sp_mr_table_ops_arr[] = {
+	{
+		.is_route_valid = mlxsw_sp_mr_route4_validate,
+		.key_create = mlxsw_sp_mr_route4_key,
+		.is_route_starg = mlxsw_sp_mr_route4_starg,
+	},
+};
+
 struct mlxsw_sp_mr_table *mlxsw_sp_mr_table_create(struct mlxsw_sp *mlxsw_sp,
 						   u32 vr_id,
 						   enum mlxsw_sp_l3proto proto)
@@ -867,6 +897,7 @@ struct mlxsw_sp_mr_table *mlxsw_sp_mr_table_create(struct mlxsw_sp *mlxsw_sp,
 	mr_table->vr_id = vr_id;
 	mr_table->mlxsw_sp = mlxsw_sp;
 	mr_table->proto = proto;
+	mr_table->ops = &mlxsw_sp_mr_table_ops_arr[proto];
 	INIT_LIST_HEAD(&mr_table->route_list);
 
 	err = rhashtable_init(&mr_table->route_ht,
@@ -877,6 +908,7 @@ struct mlxsw_sp_mr_table *mlxsw_sp_mr_table_create(struct mlxsw_sp *mlxsw_sp,
 	for (i = 0; i < MAXVIFS; i++) {
 		INIT_LIST_HEAD(&mr_table->vifs[i].route_evif_list);
 		INIT_LIST_HEAD(&mr_table->vifs[i].route_ivif_list);
+		mr_table->vifs[i].ops = &mlxsw_sp_mr_vif_ops_arr[proto];
 	}
 
 	err = mr->mr_ops->route_create(mlxsw_sp, mr->priv,
@@ -943,18 +975,10 @@ static void mlxsw_sp_mr_route_stats_update(struct mlxsw_sp *mlxsw_sp,
 	mr->mr_ops->route_stats(mlxsw_sp, mr_route->route_priv, &packets,
 				&bytes);
 
-	switch (mr_route->mr_table->proto) {
-	case MLXSW_SP_L3_PROTO_IPV4:
-		if (mr_route->mfc4->_c.mfc_un.res.pkt != packets)
-			mr_route->mfc4->_c.mfc_un.res.lastuse = jiffies;
-		mr_route->mfc4->_c.mfc_un.res.pkt = packets;
-		mr_route->mfc4->_c.mfc_un.res.bytes = bytes;
-		break;
-	case MLXSW_SP_L3_PROTO_IPV6:
-		/* fall through */
-	default:
-		WARN_ON_ONCE(1);
-	}
+	if (mr_route->mfc->mfc_un.res.pkt != packets)
+		mr_route->mfc->mfc_un.res.lastuse = jiffies;
+	mr_route->mfc->mfc_un.res.pkt = packets;
+	mr_route->mfc->mfc_un.res.bytes = bytes;
 }
 
 static void mlxsw_sp_mr_stats_update(struct work_struct *work)