net/mlx5e: Make TC and IPsec offloads mutually exclusive on a netdev

For IPsec packet offload mode, the order of TC offload and IPsec
offload on the same netdevice is not aligned with the order in the
non-offload software. For example, for RX, the software performs TC
first and then IPsec transformation, but the implementation for
offload does that in the opposite way.

To resolve the difference for now, either IPsec offload or TC offload,
not both, is allowed for a specific interface.

Signed-off-by: Jianbo Liu <[email protected]>
Signed-off-by: Leon Romanovsky <[email protected]>
Link: https://lore.kernel.org/r/8e2e5e3b0984d785066e8663aaf97b3ba1bb873f.1690802064.git.leon@kernel.org
Signed-off-by: Jakub Kicinski <[email protected]>

Author: Jianbo Liu

drivers/net/ethernet/mellanox/mlx5/core/en_accel/ipsec_fs.c

@@ -1717,12 +1717,68 @@ void mlx5e_accel_ipsec_fs_read_stats(struct mlx5e_priv *priv, void *ipsec_stats)
 	}
 }
 
+#ifdef CONFIG_MLX5_ESWITCH
+static int mlx5e_ipsec_block_tc_offload(struct mlx5_core_dev *mdev)
+{
+	struct mlx5_eswitch *esw = mdev->priv.eswitch;
+	int err = 0;
+
+	if (esw)
+		down_write(&esw->mode_lock);
+
+	if (mdev->num_block_ipsec) {
+		err = -EBUSY;
+		goto unlock;
+	}
+
+	mdev->num_block_tc++;
+
+unlock:
+	if (esw)
+		up_write(&esw->mode_lock);
+
+	return err;
+}
+#else
+static int mlx5e_ipsec_block_tc_offload(struct mlx5_core_dev *mdev)
+{
+	if (mdev->num_block_ipsec)
+		return -EBUSY;
+
+	mdev->num_block_tc++;
+	return 0;
+}
+#endif
+
+static void mlx5e_ipsec_unblock_tc_offload(struct mlx5_core_dev *mdev)
+{
+	mdev->num_block_tc++;
+}
+
 int mlx5e_accel_ipsec_fs_add_rule(struct mlx5e_ipsec_sa_entry *sa_entry)
 {
+	int err;
+
+	if (sa_entry->attrs.type == XFRM_DEV_OFFLOAD_PACKET) {
+		err = mlx5e_ipsec_block_tc_offload(sa_entry->ipsec->mdev);
+		if (err)
+			return err;
+	}
+
 	if (sa_entry->attrs.dir == XFRM_DEV_OFFLOAD_OUT)
-		return tx_add_rule(sa_entry);
+		err = tx_add_rule(sa_entry);
+	else
+		err = rx_add_rule(sa_entry);
+
+	if (err)
+		goto err_out;
+
+	return 0;
 
-	return rx_add_rule(sa_entry);
+err_out:
+	if (sa_entry->attrs.type == XFRM_DEV_OFFLOAD_PACKET)
+		mlx5e_ipsec_unblock_tc_offload(sa_entry->ipsec->mdev);
+	return err;
 }
 
 void mlx5e_accel_ipsec_fs_del_rule(struct mlx5e_ipsec_sa_entry *sa_entry)
@@ -1735,6 +1791,9 @@ void mlx5e_accel_ipsec_fs_del_rule(struct mlx5e_ipsec_sa_entry *sa_entry)
 	if (ipsec_rule->pkt_reformat)
 		mlx5_packet_reformat_dealloc(mdev, ipsec_rule->pkt_reformat);
 
+	if (sa_entry->attrs.type == XFRM_DEV_OFFLOAD_PACKET)
+		mlx5e_ipsec_unblock_tc_offload(mdev);
+
 	if (sa_entry->attrs.dir == XFRM_DEV_OFFLOAD_OUT) {
 		tx_ft_put(sa_entry->ipsec, sa_entry->attrs.type);
 		return;
@@ -1747,10 +1806,25 @@ void mlx5e_accel_ipsec_fs_del_rule(struct mlx5e_ipsec_sa_entry *sa_entry)
 
 int mlx5e_accel_ipsec_fs_add_pol(struct mlx5e_ipsec_pol_entry *pol_entry)
 {
+	int err;
+
+	err = mlx5e_ipsec_block_tc_offload(pol_entry->ipsec->mdev);
+	if (err)
+		return err;
+
 	if (pol_entry->attrs.dir == XFRM_DEV_OFFLOAD_OUT)
-		return tx_add_policy(pol_entry);
+		err = tx_add_policy(pol_entry);
+	else
+		err = rx_add_policy(pol_entry);
+
+	if (err)
+		goto err_out;
+
+	return 0;
 
-	return rx_add_policy(pol_entry);
+err_out:
+	mlx5e_ipsec_unblock_tc_offload(pol_entry->ipsec->mdev);
+	return err;
 }
 
 void mlx5e_accel_ipsec_fs_del_pol(struct mlx5e_ipsec_pol_entry *pol_entry)
@@ -1760,6 +1834,8 @@ void mlx5e_accel_ipsec_fs_del_pol(struct mlx5e_ipsec_pol_entry *pol_entry)
 
 	mlx5_del_flow_rules(ipsec_rule->rule);
 
+	mlx5e_ipsec_unblock_tc_offload(pol_entry->ipsec->mdev);
+
 	if (pol_entry->attrs.dir == XFRM_DEV_OFFLOAD_IN) {
 		rx_ft_put_policy(pol_entry->ipsec, pol_entry->attrs.family,
 				 pol_entry->attrs.prio, pol_entry->attrs.type);

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

@@ -4606,6 +4606,46 @@ static bool is_flow_rule_duplicate_allowed(struct net_device *dev,
 	return netif_is_lag_port(dev) && rpriv && rpriv->rep->vport != MLX5_VPORT_UPLINK;
 }
 
+/* As IPsec and TC order is not aligned between software and hardware-offload,
+ * either IPsec offload or TC offload, not both, is allowed for a specific interface.
+ */
+static bool is_tc_ipsec_order_check_needed(struct net_device *filter, struct mlx5e_priv *priv)
+{
+	if (!IS_ENABLED(CONFIG_MLX5_EN_IPSEC))
+		return false;
+
+	if (filter != priv->netdev)
+		return false;
+
+	if (mlx5e_eswitch_vf_rep(priv->netdev))
+		return false;
+
+	return true;
+}
+
+static int mlx5e_tc_block_ipsec_offload(struct net_device *filter, struct mlx5e_priv *priv)
+{
+	struct mlx5_core_dev *mdev = priv->mdev;
+
+	if (!is_tc_ipsec_order_check_needed(filter, priv))
+		return 0;
+
+	if (mdev->num_block_tc)
+		return -EBUSY;
+
+	mdev->num_block_ipsec++;
+
+	return 0;
+}
+
+static void mlx5e_tc_unblock_ipsec_offload(struct net_device *filter, struct mlx5e_priv *priv)
+{
+	if (!is_tc_ipsec_order_check_needed(filter, priv))
+		return;
+
+	priv->mdev->num_block_ipsec--;
+}
+
 int mlx5e_configure_flower(struct net_device *dev, struct mlx5e_priv *priv,
 			   struct flow_cls_offload *f, unsigned long flags)
 {
@@ -4618,6 +4658,10 @@ int mlx5e_configure_flower(struct net_device *dev, struct mlx5e_priv *priv,
 	if (!mlx5_esw_hold(priv->mdev))
 		return -EBUSY;
 
+	err = mlx5e_tc_block_ipsec_offload(dev, priv);
+	if (err)
+		goto esw_release;
+
 	mlx5_esw_get(priv->mdev);
 
 	rcu_read_lock();
@@ -4663,7 +4707,9 @@ int mlx5e_configure_flower(struct net_device *dev, struct mlx5e_priv *priv,
 err_free:
 	mlx5e_flow_put(priv, flow);
 out:
+	mlx5e_tc_unblock_ipsec_offload(dev, priv);
 	mlx5_esw_put(priv->mdev);
+esw_release:
 	mlx5_esw_release(priv->mdev);
 	return err;
 }
@@ -4704,6 +4750,7 @@ int mlx5e_delete_flower(struct net_device *dev, struct mlx5e_priv *priv,
 	trace_mlx5e_delete_flower(f);
 	mlx5e_flow_put(priv, flow);
 
+	mlx5e_tc_unblock_ipsec_offload(dev, priv);
 	mlx5_esw_put(priv->mdev);
 	return 0;
 

include/linux/mlx5/driver.h

@@ -806,6 +806,8 @@ struct mlx5_core_dev {
 	u32                      vsc_addr;
 	struct mlx5_hv_vhca	*hv_vhca;
 	struct mlx5_thermal	*thermal;
+	u64			num_block_tc;
+	u64			num_block_ipsec;
 };
 
 struct mlx5_db {