net/mlx5: Bridge, add offload infrastructure

Create new files bridge.{c|h} in en/rep directory that implement bridge
interaction with representor netdevices and handle required
events/notifications, bridge.{c|h} in esw directory that implement all
necessary eswitch offloading infrastructure and works on vport/eswitch
level. Provide new kconfig MLX5_BRIDGE which is automatically selected when
both kernel bridge and mlx5 eswitch configs are enabled.

Provide basic infrastructure for bridge offloads:

- struct mlx5_esw_bridge_offloads - per-eswitch bridge offload structure
that encapsulates generic bridge-offloads data (notifier blocks, ingress
flow table/group, etc.) that is created/deleted on enable/disable eswitch
offloads.

- struct mlx5_esw_bridge - per-bridge structure that encapsulates
per-bridge data (reference counter, FDB, egress flow table/group, etc.)
that is created when first eswitch represetor is attached to new bridge and
deleted when last representor is removed from the bridge as a result of
NETDEV_CHANGEUPPER event.

The bridge tables are created with new priority FDB_BR_OFFLOAD in FDB
namespace. The new priority is between tc-miss and slow path priorities.
Priority consist of two levels: the ingress table that is global per
eswitch and matches incoming packets by src_mac/vid and redirects them to
next level (egress table) that is chosen according to ingress port bridge
membership and matches on dst_mac/vid in order to redirect packet to vport
according to the following diagram:

                +
                |
      +---------v----------+
      |                    |
      |   FDB_TC_OFFLOAD   |
      |                    |
      +---------+----------+
                |
                |
      +---------v----------+
      |                    |
      |   FDB_FT_OFFLOAD   |
      |                    |
      +---------+----------+
                |
                |
      +---------v----------+
      |                    |
      |    FDB_TC_MISS     |
      |                    |
      +---------+----------+
                |
+--------------------------------------+
|               |                      |
|        +------+                      |
|        |                             |
| +------v--------+   FDB_BR_OFFLOAD   |
| | INGRESS_TABLE |                    |
| +------+---+----+                    |
|        |   |      match              |
|        |   +---------+               |
|        |             |               |    +-------+
|        |     +-------v-------+ match |    |       |
|        |     | EGRESS_TABLE  +------------> vport |
|        |     +-------+-------+       |    |       |
|        |             |               |    +-------+
|        |    miss     |               |
|        +------+------+               |
|               |                      |
+--------------------------------------+
                |
                |
      +---------v----------+
      |                    |
      |   FDB_SLOW_PATH    |
      |                    |
      +---------+----------+
                |
                v

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/esw/bridge.h b/drivers/net/ethernet/mellanox/mlx5/core/esw/bridge.h
new file mode 100644
index 000000000000..319b6f1db0ba
--- /dev/null
+++ b/drivers/net/ethernet/mellanox/mlx5/core/esw/bridge.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/* Copyright (c) 2021 Mellanox Technologies. */
+
+#ifndef __MLX5_ESW_BRIDGE_H__
+#define __MLX5_ESW_BRIDGE_H__
+
+#include <linux/notifier.h>
+#include <linux/list.h>
+#include "eswitch.h"
+
+struct mlx5_flow_table;
+struct mlx5_flow_group;
+
+struct mlx5_esw_bridge_offloads {
+	struct mlx5_eswitch *esw;
+	struct list_head bridges;
+	struct notifier_block netdev_nb;
+
+	struct mlx5_flow_table *ingress_ft;
+	struct mlx5_flow_group *ingress_mac_fg;
+};
+
+struct mlx5_esw_bridge_offloads *mlx5_esw_bridge_init(struct mlx5_eswitch *esw);
+void mlx5_esw_bridge_cleanup(struct mlx5_eswitch *esw);
+int mlx5_esw_bridge_vport_link(int ifindex, struct mlx5_esw_bridge_offloads *br_offloads,
+			       struct mlx5_vport *vport, struct netlink_ext_ack *extack);
+int mlx5_esw_bridge_vport_unlink(int ifindex, struct mlx5_esw_bridge_offloads *br_offloads,
+				 struct mlx5_vport *vport, struct netlink_ext_ack *extack);
+
+#endif /* __MLX5_ESW_BRIDGE_H__ */