net/mlx5: Lag, refactor disable flow

When a net device is removed (can happen if the PCI function is unbound
from the system) it's not enough to destroy the hardware lag. The system
should recreate the original devices that were present before the lag.
As the same flow is done when a net device is removed from the bond
refactor and reuse the code.
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

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

@@ -276,6 +276,29 @@ static void mlx5_lag_remove_devices(struct mlx5_lag *ldev)
 	}
 }
 
+static void mlx5_disable_lag(struct mlx5_lag *ldev)
+{
+	struct mlx5_core_dev *dev0 = ldev->pf[MLX5_LAG_P1].dev;
+	struct mlx5_core_dev *dev1 = ldev->pf[MLX5_LAG_P2].dev;
+	bool roce_lag;
+	int err;
+
+	roce_lag = __mlx5_lag_is_roce(ldev);
+
+	if (roce_lag) {
+		dev0->priv.flags |= MLX5_PRIV_FLAGS_DISABLE_IB_ADEV;
+		mlx5_rescan_drivers_locked(dev0);
+		mlx5_nic_vport_disable_roce(dev1);
+	}
+
+	err = mlx5_deactivate_lag(ldev);
+	if (err)
+		return;
+
+	if (roce_lag)
+		mlx5_lag_add_devices(ldev);
+}
+
 static void mlx5_do_bond(struct mlx5_lag *ldev)
 {
 	struct mlx5_core_dev *dev0 = ldev->pf[MLX5_LAG_P1].dev;
@@ -322,20 +345,7 @@ static void mlx5_do_bond(struct mlx5_lag *ldev)
 	} else if (do_bond && __mlx5_lag_is_active(ldev)) {
 		mlx5_modify_lag(ldev, &tracker);
 	} else if (!do_bond && __mlx5_lag_is_active(ldev)) {
-		roce_lag = __mlx5_lag_is_roce(ldev);
-
-		if (roce_lag) {
-			dev0->priv.flags |= MLX5_PRIV_FLAGS_DISABLE_IB_ADEV;
-			mlx5_rescan_drivers_locked(dev0);
-			mlx5_nic_vport_disable_roce(dev1);
-		}
-
-		err = mlx5_deactivate_lag(ldev);
-		if (err)
-			return;
-
-		if (roce_lag)
-			mlx5_lag_add_devices(ldev);
+		mlx5_disable_lag(ldev);
 	}
 }
 
@@ -620,7 +630,7 @@ void mlx5_lag_remove(struct mlx5_core_dev *dev)
 		return;
 
 	if (__mlx5_lag_is_active(ldev))
-		mlx5_deactivate_lag(ldev);
+		mlx5_disable_lag(ldev);
 
 	mlx5_lag_dev_remove_pf(ldev, dev);