net/mlx5: E-Switch, Add chains and priorities

A chain is a group of priorities, so use the fdb parallel
sub namespaces to implement chains, and a flow table for each
priority in them.

Because these namespaces are parallel and in series to the slow path
fdb, the chains aren't connected to one another (but to the slow path),
and one must use a explicit goto action to reach a different chain.

Flow tables for the priorities will be created on demand and destroyed
once not used.

The Firmware has four pools of tables for sizes S/XS/M/L (4k, 64k, 1m, 4m).
We maintain ghost copies of the pools occupancy.

When a new table is to be created, we scan the pools from large to small
and find the 1st table size which can be now created. When a table is
destroyed, we update the relevant pool.

Multi chain/prio isn't enabled yet by this patch, for now all flows
will use the default chain 0, and prio 1.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -837,6 +837,9 @@ mlx5e_tc_add_fdb_flow(struct mlx5e_priv *priv,
 	struct mlx5e_priv *out_priv;
 	int err = 0, encap_err = 0;
 
+	/* keep the old behaviour, use same prio for all offloaded rules */
+	attr->prio = 1;
+
 	if (attr->action & MLX5_FLOW_CONTEXT_ACTION_PACKET_REFORMAT) {
 		out_dev = __dev_get_by_index(dev_net(priv->netdev),
 					     attr->parse_attr->mirred_ifindex);

drivers/net/ethernet/mellanox/mlx5/core/eswitch.h

@@ -123,6 +123,13 @@ struct mlx5_vport {
 	u16                     enabled_events;
 };
 
+enum offloads_fdb_flags {
+	ESW_FDB_CHAINS_AND_PRIOS_SUPPORTED = BIT(0),
+};
+
+extern const unsigned int ESW_POOLS[4];
+
+#define PRIO_LEVELS 2
 struct mlx5_eswitch_fdb {
 	union {
 		struct legacy_fdb {
@@ -133,16 +140,24 @@ struct mlx5_eswitch_fdb {
 		} legacy;
 
 		struct offloads_fdb {
-			struct mlx5_flow_table *fast_fdb;
-			struct mlx5_flow_table *fwd_fdb;
 			struct mlx5_flow_table *slow_fdb;
 			struct mlx5_flow_group *send_to_vport_grp;
 			struct mlx5_flow_group *miss_grp;
 			struct mlx5_flow_handle *miss_rule_uni;
 			struct mlx5_flow_handle *miss_rule_multi;
 			int vlan_push_pop_refcount;
+
+			struct {
+				struct mlx5_flow_table *fdb;
+				u32 num_rules;
+			} fdb_prio[FDB_MAX_CHAIN + 1][FDB_MAX_PRIO + 1][PRIO_LEVELS];
+			/* Protects fdb_prio table */
+			struct mutex fdb_prio_lock;
+
+			int fdb_left[ARRAY_SIZE(ESW_POOLS)];
 		} offloads;
 	};
+	u32 flags;
 };
 
 struct mlx5_esw_offload {
@@ -184,6 +199,7 @@ struct mlx5_eswitch {
 
 	struct mlx5_esw_offload offloads;
 	int                     mode;
+	int                     nvports;
 };
 
 void esw_offloads_cleanup(struct mlx5_eswitch *esw, int nvports);
@@ -236,6 +252,15 @@ mlx5_eswitch_del_fwd_rule(struct mlx5_eswitch *esw,
 			  struct mlx5_flow_handle *rule,
 			  struct mlx5_esw_flow_attr *attr);
 
+bool
+mlx5_eswitch_prios_supported(struct mlx5_eswitch *esw);
+
+u16
+mlx5_eswitch_get_prio_range(struct mlx5_eswitch *esw);
+
+u32
+mlx5_eswitch_get_chain_range(struct mlx5_eswitch *esw);
+
 struct mlx5_flow_handle *
 mlx5_eswitch_create_vport_rx_rule(struct mlx5_eswitch *esw, int vport,
 				  struct mlx5_flow_destination *dest);
@@ -274,6 +299,9 @@ struct mlx5_esw_flow_attr {
 	u32	mod_hdr_id;
 	u8	match_level;
 	struct mlx5_fc *counter;
+	u32	chain;
+	u16	prio;
+	u32	dest_chain;
 	struct mlx5e_tc_flow_parse_attr *parse_attr;
 };