[PATCH net-next 14/15] net/mlx5e: Return errors from profile->enable

[Tariq Toukan <tariqt@nvidia.com>]

From: Cosmin Ratiu <cratiu@nvidia.com>

profile->enable is called before enabling an mlx5 netdevice and
currently doesn't return errors. Code called from it has to either:
1. eat errors and keep going, leaving a netdevice initialized with
   missing functionality
or
2. manually clean up things that other parts of the init flow might have
   set up.

Option 1 might be useful in some cases for optional functionality but
option 2 doesn't make for good design.

Add a 3rd option for code which wants to propagate errors from
profile->enable and fail netdev init. This change is a noop for now, the
first 'user' of this option 3 will be in the next patch.

Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en.h      |  2 +-
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 15 +++++++++++----
 drivers/net/ethernet/mellanox/mlx5/core/en_rep.c  |  8 ++++++--
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en.h b/drivers/net/ethernet/mellanox/mlx5/core/en.h
index 2270e2e550dd..3cc7283b6215 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en.h
@@ -1016,7 +1016,7 @@ struct mlx5e_profile {
 	void	(*cleanup_rx)(struct mlx5e_priv *priv);
 	int	(*init_tx)(struct mlx5e_priv *priv);
 	void	(*cleanup_tx)(struct mlx5e_priv *priv);
-	void	(*enable)(struct mlx5e_priv *priv);
+	int	(*enable)(struct mlx5e_priv *priv);
 	void	(*disable)(struct mlx5e_priv *priv);
 	int	(*update_rx)(struct mlx5e_priv *priv);
 	void	(*update_stats)(struct mlx5e_priv *priv);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index 775f0c6e55c9..9eadd0b6f055 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -6191,7 +6191,7 @@ static int mlx5e_init_nic_tx(struct mlx5e_priv *priv)
 	return 0;
 }
 
-static void mlx5e_nic_enable(struct mlx5e_priv *priv)
+static int mlx5e_nic_enable(struct mlx5e_priv *priv)
 {
 	struct net_device *netdev = priv->netdev;
 	struct mlx5_core_dev *mdev = priv->mdev;
@@ -6222,7 +6222,7 @@ static void mlx5e_nic_enable(struct mlx5e_priv *priv)
 	mlx5e_pcie_cong_event_init(priv);
 	mlx5e_hv_vhca_stats_create(priv);
 	if (netdev->reg_state != NETREG_REGISTERED)
-		return;
+		return 0;
 	mlx5e_dcbnl_init_app(priv);
 
 	mlx5e_nic_set_rx_mode(priv);
@@ -6235,6 +6235,8 @@ static void mlx5e_nic_enable(struct mlx5e_priv *priv)
 	netdev_unlock(netdev);
 	netif_device_attach(netdev);
 	rtnl_unlock();
+
+	return 0;
 }
 
 static void mlx5e_nic_disable(struct mlx5e_priv *priv)
@@ -6616,13 +6618,18 @@ int mlx5e_attach_netdev(struct mlx5e_priv *priv)
 	if (err)
 		goto err_cleanup_tx;
 
-	if (profile->enable)
-		profile->enable(priv);
+	if (profile->enable) {
+		err = profile->enable(priv);
+		if (err)
+			goto err_cleanup_rx;
+	}
 
 	mlx5e_update_features(priv->netdev);
 
 	return 0;
 
+err_cleanup_rx:
+	profile->cleanup_rx(priv);
 err_cleanup_tx:
 	profile->cleanup_tx(priv);
 
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
index c8b76d301c92..603051ab1eaa 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rep.c
@@ -1262,9 +1262,11 @@ static void mlx5e_cleanup_rep_tx(struct mlx5e_priv *priv)
 	mlx5e_rep_neigh_cleanup(rpriv);
 }
 
-static void mlx5e_rep_enable(struct mlx5e_priv *priv)
+static int mlx5e_rep_enable(struct mlx5e_priv *priv)
 {
 	mlx5e_set_netdev_mtu_boundaries(priv);
+
+	return 0;
 }
 
 static void mlx5e_rep_disable(struct mlx5e_priv *priv)
@@ -1322,7 +1324,7 @@ static int uplink_rep_async_event(struct notifier_block *nb, unsigned long event
 	return NOTIFY_DONE;
 }
 
-static void mlx5e_uplink_rep_enable(struct mlx5e_priv *priv)
+static int mlx5e_uplink_rep_enable(struct mlx5e_priv *priv)
 {
 	struct net_device *netdev = priv->netdev;
 	struct mlx5_core_dev *mdev = priv->mdev;
@@ -1357,6 +1359,8 @@ static void mlx5e_uplink_rep_enable(struct mlx5e_priv *priv)
 	netdev_unlock(netdev);
 	netif_device_attach(netdev);
 	rtnl_unlock();
+
+	return 0;
 }
 
 static void mlx5e_uplink_rep_disable(struct mlx5e_priv *priv)
-- 
2.44.0