From: Tariq Toukan <tariqt@mellanox.com>

Date: Mon, 18 Nov 2019 11:41:04 +0200

Subject: net/mlx4_en: Fix wrong limitation for number of TX rings

Patch-mainline: v5.4

Git-commit: 2744bf42680f64ebf2ee8a00354897857c073331

References: bsc#1103989 FATE#326004

XDP_TX rings should not be limited by max_num_tx_rings_p_up.

To make sure total number of TX rings never exceed MAX_TX_RINGS,

add similar check in mlx4_en_alloc_tx_queue_per_tc(), where

a new value is assigned for num_up.

Fixes: 7e1dc5e926d5 ("net/mlx4_en: Limit the number of TX rings")

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

Signed-off-by: David S. Miller <davem@davemloft.net>

Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>

---

 drivers/net/ethernet/mellanox/mlx4/en_ethtool.c |    8 ++++----

 drivers/net/ethernet/mellanox/mlx4/en_netdev.c  |    9 +++++++++

 2 files changed, 13 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c

+++ b/drivers/net/ethernet/mellanox/mlx4/en_ethtool.c

@@ -1811,6 +1811,7 @@ static int mlx4_en_set_channels(struct n

 	struct mlx4_en_dev *mdev = priv->mdev;

 	struct mlx4_en_port_profile new_prof;

 	struct mlx4_en_priv *tmp;

+	int total_tx_count;

 	int port_up = 0;

 	int xdp_count;

 	int err = 0;

@@ -1825,13 +1826,12 @@ static int mlx4_en_set_channels(struct n

 	mutex_lock(&mdev->state_lock);

 	xdp_count = priv->tx_ring_num[TX_XDP] ? channel->rx_count : 0;

-	if (channel->tx_count * priv->prof->num_up + xdp_count >

-	    priv->mdev->profile.max_num_tx_rings_p_up * priv->prof->num_up) {

+	total_tx_count = channel->tx_count * priv->prof->num_up + xdp_count;

+	if (total_tx_count > MAX_TX_RINGS) {

 		err = -EINVAL;

 		en_err(priv,

 		       "Total number of TX and XDP rings (%d) exceeds the maximum supported (%d)\n",

-		       channel->tx_count * priv->prof->num_up  + xdp_count,

-		       MAX_TX_RINGS);

+		       total_tx_count, MAX_TX_RINGS);

 		goto out;

 	}

--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c

+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c

@@ -91,6 +91,7 @@ int mlx4_en_alloc_tx_queue_per_tc(struct

 	struct mlx4_en_dev *mdev = priv->mdev;

 	struct mlx4_en_port_profile new_prof;

 	struct mlx4_en_priv *tmp;

+	int total_count;

 	int port_up = 0;

 	int err = 0;

@@ -104,6 +105,14 @@ int mlx4_en_alloc_tx_queue_per_tc(struct

 				      MLX4_EN_NUM_UP_HIGH;

 	new_prof.tx_ring_num[TX] = new_prof.num_tx_rings_p_up *

 				   new_prof.num_up;

+	total_count = new_prof.tx_ring_num[TX] + new_prof.tx_ring_num[TX_XDP];

+	if (total_count > MAX_TX_RINGS) {

+		err = -EINVAL;

+		en_err(priv,

+		       "Total number of TX and XDP rings (%d) exceeds the maximum supported (%d)\n",

+		       total_count, MAX_TX_RINGS);

+		goto out;

+	}

 	err = mlx4_en_try_alloc_resources(priv, tmp, &new_prof, true);

 	if (err)

 		goto out;