net/mlx5e: Unify logic of MTU boundaries

Expose a new helper that wraps the logic for setting the
netdevice's MTU boundaries.
Use it for the different components (Eth, rep, IPoIB).

Set the netdevice min MTU to ETH_MIN_MTU, and the max according
to both the FW capability and the kernel definition.

Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

Author: Tariq Toukan

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

@@ -1086,6 +1086,7 @@ mlx5e_create_netdev(struct mlx5_core_dev *mdev, const struct mlx5e_profile *prof
 int mlx5e_attach_netdev(struct mlx5e_priv *priv);
 void mlx5e_detach_netdev(struct mlx5e_priv *priv);
 void mlx5e_destroy_netdev(struct mlx5e_priv *priv);
+void mlx5e_set_netdev_mtu_boundaries(struct mlx5e_priv *priv);
 void mlx5e_build_nic_params(struct mlx5_core_dev *mdev,
 			    struct mlx5e_rss_params *rss_params,
 			    struct mlx5e_params *params,

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

@@ -2811,6 +2811,21 @@ int mlx5e_set_dev_port_mtu(struct mlx5e_priv *priv)
 	return 0;
 }
 
+void mlx5e_set_netdev_mtu_boundaries(struct mlx5e_priv *priv)
+{
+	struct mlx5e_params *params = &priv->channels.params;
+	struct net_device *netdev   = priv->netdev;
+	struct mlx5_core_dev *mdev  = priv->mdev;
+	u16 max_mtu;
+
+	/* MTU range: 68 - hw-specific max */
+	netdev->min_mtu = ETH_MIN_MTU;
+
+	mlx5_query_port_max_mtu(mdev, &max_mtu, 1);
+	netdev->max_mtu = min_t(unsigned int, MLX5E_HW2SW_MTU(params, max_mtu),
+				ETH_MAX_MTU);
+}
+
 static void mlx5e_netdev_set_tcs(struct net_device *netdev)
 {
 	struct mlx5e_priv *priv = netdev_priv(netdev);
@@ -4912,18 +4927,14 @@ static void mlx5e_nic_enable(struct mlx5e_priv *priv)
 {
 	struct net_device *netdev = priv->netdev;
 	struct mlx5_core_dev *mdev = priv->mdev;
-	u16 max_mtu;
 
 	mlx5e_init_l2_addr(priv);
 
 	/* Marking the link as currently not needed by the Driver */
 	if (!netif_running(netdev))
 		mlx5_set_port_admin_status(mdev, MLX5_PORT_DOWN);
 
-	/* MTU range: 68 - hw-specific max */
-	netdev->min_mtu = ETH_MIN_MTU;
-	mlx5_query_port_max_mtu(priv->mdev, &max_mtu, 1);
-	netdev->max_mtu = MLX5E_HW2SW_MTU(&priv->channels.params, max_mtu);
+	mlx5e_set_netdev_mtu_boundaries(priv);
 	mlx5e_set_dev_port_mtu(priv);
 
 	mlx5_lag_add(mdev, netdev);

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

@@ -1624,13 +1624,7 @@ static void mlx5e_cleanup_rep_tx(struct mlx5e_priv *priv)
 
 static void mlx5e_vf_rep_enable(struct mlx5e_priv *priv)
 {
-	struct net_device *netdev = priv->netdev;
-	struct mlx5_core_dev *mdev = priv->mdev;
-	u16 max_mtu;
-
-	netdev->min_mtu = ETH_MIN_MTU;
-	mlx5_query_port_max_mtu(mdev, &max_mtu, 1);
-	netdev->max_mtu = MLX5E_HW2SW_MTU(&priv->channels.params, max_mtu);
+	mlx5e_set_netdev_mtu_boundaries(priv);
 }
 
 static int uplink_rep_async_event(struct notifier_block *nb, unsigned long event, void *data)

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

@@ -77,15 +77,14 @@ int mlx5i_init(struct mlx5_core_dev *mdev,
 	       void *ppriv)
 {
 	struct mlx5e_priv *priv  = mlx5i_epriv(netdev);
-	u16 max_mtu;
 	int err;
 
 	err = mlx5e_netdev_init(netdev, priv, mdev, profile, ppriv);
 	if (err)
 		return err;
 
-	mlx5_query_port_max_mtu(mdev, &max_mtu, 1);
-	netdev->mtu = max_mtu;
+	mlx5e_set_netdev_mtu_boundaries(priv);
+	netdev->mtu = netdev->max_mtu;
 
 	mlx5e_build_nic_params(mdev, &priv->rss_params, &priv->channels.params,
 			       mlx5e_get_netdev_max_channels(netdev),