net/mlx5: Lag, decouple FDB selection and shared FDB

Multiport eswitch is required to use native FDB selection instead of
affinity, This was achieved by passing the shared_fdb flag down
the HW lag creation path. While it did accomplish the goal of setting
FDB selection mode to native, it had the side effect of also
creating a shared FDB configuration.

This created a few issues:
- TC rules are inserted into a non active FDB, which means traffic isn't
  offloaded as all traffic will reach only a single FDB.
- All wire traffic is treated as if a single physical port received it; while
  this is true for a bond configuration, this shouldn't be the case for
  multiport eswitch.

Create a new flag MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE
to indicate what FDB selection mode should be used.

Fixes: 94db331778 ("net/mlx5: Support multiport eswitch mode")
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Reviewed-by: Eli Cohen <elic@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/lag/debugfs.c

@@ -72,6 +72,7 @@ static int state_show(struct seq_file *file, void *priv)
 static int flags_show(struct seq_file *file, void *priv)
 {
 	struct mlx5_core_dev *dev = file->private;
+	bool fdb_sel_mode_native;
 	struct mlx5_lag *ldev;
 	bool shared_fdb;
 	bool lag_active;
@@ -79,14 +80,21 @@ static int flags_show(struct seq_file *file, void *priv)
 	ldev = dev->priv.lag;
 	mutex_lock(&ldev->lock);
 	lag_active = __mlx5_lag_is_active(ldev);
-	if (lag_active)
+	if (!lag_active)
-		shared_fdb = test_bit(MLX5_LAG_MODE_FLAG_SHARED_FDB, &ldev->mode_flags);
+		goto unlock;
 
+	shared_fdb = test_bit(MLX5_LAG_MODE_FLAG_SHARED_FDB, &ldev->mode_flags);
+	fdb_sel_mode_native = test_bit(MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE,
+				       &ldev->mode_flags);
+
+unlock:
 	mutex_unlock(&ldev->lock);
 	if (!lag_active)
 		return -EINVAL;
 
 	seq_printf(file, "%s:%s\n", "shared_fdb", shared_fdb ? "on" : "off");
+	seq_printf(file, "%s:%s\n", "fdb_selection_mode",
+		   fdb_sel_mode_native ? "native" : "affinity");
 	return 0;
 }
 

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

@@ -68,14 +68,15 @@ static int get_port_sel_mode(enum mlx5_lag_mode mode, unsigned long flags)
 static int mlx5_cmd_create_lag(struct mlx5_core_dev *dev, u8 *ports, int mode,
 			       unsigned long flags)
 {
-	bool shared_fdb = test_bit(MLX5_LAG_MODE_FLAG_SHARED_FDB, &flags);
+	bool fdb_sel_mode = test_bit(MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE,
+				     &flags);
 	int port_sel_mode = get_port_sel_mode(mode, flags);
 	u32 in[MLX5_ST_SZ_DW(create_lag_in)] = {};
 	void *lag_ctx;
 
 	lag_ctx = MLX5_ADDR_OF(create_lag_in, in, ctx);
 	MLX5_SET(create_lag_in, in, opcode, MLX5_CMD_OP_CREATE_LAG);
-	MLX5_SET(lagc, lag_ctx, fdb_selection_mode, shared_fdb);
+	MLX5_SET(lagc, lag_ctx, fdb_selection_mode, fdb_sel_mode);
 	if (port_sel_mode == MLX5_LAG_PORT_SELECT_MODE_QUEUE_AFFINITY) {
 		MLX5_SET(lagc, lag_ctx, tx_remap_affinity_1, ports[0]);
 		MLX5_SET(lagc, lag_ctx, tx_remap_affinity_2, ports[1]);
@@ -471,8 +472,13 @@ static int mlx5_lag_set_flags(struct mlx5_lag *ldev, enum mlx5_lag_mode mode,
 	bool roce_lag = mode == MLX5_LAG_MODE_ROCE;
 
 	*flags = 0;
-	if (shared_fdb)
+	if (shared_fdb) {
 		set_bit(MLX5_LAG_MODE_FLAG_SHARED_FDB, flags);
+		set_bit(MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE, flags);
+	}
+
+	if (mode == MLX5_LAG_MODE_MPESW)
+		set_bit(MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE, flags);
 
 	if (roce_lag)
 		return mlx5_lag_set_port_sel_mode_roce(ldev, flags);

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

@@ -24,6 +24,7 @@ enum {
 enum {
 	MLX5_LAG_MODE_FLAG_HASH_BASED,
 	MLX5_LAG_MODE_FLAG_SHARED_FDB,
+	MLX5_LAG_MODE_FLAG_FDB_SEL_MODE_NATIVE,
 };
 
 enum mlx5_lag_mode {

drivers/net/ethernet/mellanox/mlx5/core/lag/mpesw.c

@@ -41,7 +41,6 @@ void mlx5_lag_del_mpesw_rule(struct mlx5_core_dev *dev)
 int mlx5_lag_add_mpesw_rule(struct mlx5_core_dev *dev)
 {
 	struct mlx5_lag *ldev = dev->priv.lag;
-	bool shared_fdb;
 	int err = 0;
 
 	if (!ldev)
@@ -55,8 +54,8 @@ int mlx5_lag_add_mpesw_rule(struct mlx5_core_dev *dev)
 		err = -EINVAL;
 		goto out;
 	}
-	shared_fdb = mlx5_shared_fdb_supported(ldev);
+
-	err = mlx5_activate_lag(ldev, NULL, MLX5_LAG_MODE_MPESW, shared_fdb);
+	err = mlx5_activate_lag(ldev, NULL, MLX5_LAG_MODE_MPESW, false);
 	if (err)
 		mlx5_core_warn(dev, "Failed to create LAG in MPESW mode (%d)\n", err);