{net,ib}/mlx5: Don't disable local loopback multicast traffic when needed

There are systems platform information management interfaces (such as
HOST2BMC) for which we cannot disable local loopback multicast traffic.

Separate disable_local_lb_mc and disable_local_lb_uc capability bits so
driver will not disable multicast loopback traffic if not supported.
(It is expected that Firmware will not set disable_local_lb_mc if
HOST2BMC is running for example.)

Function mlx5_nic_vport_update_local_lb will do best effort to
disable/enable UC/MC loopback traffic and return success only in case it
succeeded to changed all allowed by Firmware.

Adapt mlx5_ib and mlx5e to support the new cap bits.

Fixes: 2c43c5a0 ("net/mlx5e: Enable local loopback in loopback selftest")
Fixes: c85023e1 ("IB/mlx5: Add raw ethernet local loopback support")
Fixes: bded747b ("net/mlx5: Add raw ethernet local loopback firmware command")
Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Cc: kernel-team@fb.com
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

drivers/infiniband/hw/mlx5/main.c

@@ -1324,7 +1324,8 @@ static int mlx5_ib_alloc_transport_domain(struct mlx5_ib_dev *dev, u32 *tdn)
 		return err;
 
 	if ((MLX5_CAP_GEN(dev->mdev, port_type) != MLX5_CAP_PORT_TYPE_ETH) ||
-	    !MLX5_CAP_GEN(dev->mdev, disable_local_lb))
+	    (!MLX5_CAP_GEN(dev->mdev, disable_local_lb_uc) &&
+	     !MLX5_CAP_GEN(dev->mdev, disable_local_lb_mc)))
 		return err;
 
 	mutex_lock(&dev->lb_mutex);
@@ -1342,7 +1343,8 @@ static void mlx5_ib_dealloc_transport_domain(struct mlx5_ib_dev *dev, u32 tdn)
 	mlx5_core_dealloc_transport_domain(dev->mdev, tdn);
 
 	if ((MLX5_CAP_GEN(dev->mdev, port_type) != MLX5_CAP_PORT_TYPE_ETH) ||
-	    !MLX5_CAP_GEN(dev->mdev, disable_local_lb))
+	    (!MLX5_CAP_GEN(dev->mdev, disable_local_lb_uc) &&
+	     !MLX5_CAP_GEN(dev->mdev, disable_local_lb_mc)))
 		return;
 
 	mutex_lock(&dev->lb_mutex);
@@ -4187,7 +4189,8 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
 	}
 
 	if ((MLX5_CAP_GEN(mdev, port_type) == MLX5_CAP_PORT_TYPE_ETH) &&
-	    MLX5_CAP_GEN(mdev, disable_local_lb))
+	    (MLX5_CAP_GEN(mdev, disable_local_lb_uc) ||
+	     MLX5_CAP_GEN(mdev, disable_local_lb_mc)))
 		mutex_init(&dev->lb_mutex);
 
 	dev->ib_active = true;

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

@@ -238,15 +238,19 @@ static int mlx5e_test_loopback_setup(struct mlx5e_priv *priv,
 	int err = 0;
 
 	/* Temporarily enable local_lb */
-	if (MLX5_CAP_GEN(priv->mdev, disable_local_lb)) {
-		mlx5_nic_vport_query_local_lb(priv->mdev, &lbtp->local_lb);
-		if (!lbtp->local_lb)
-			mlx5_nic_vport_update_local_lb(priv->mdev, true);
+	err = mlx5_nic_vport_query_local_lb(priv->mdev, &lbtp->local_lb);
+	if (err)
+		return err;
+
+	if (!lbtp->local_lb) {
+		err = mlx5_nic_vport_update_local_lb(priv->mdev, true);
+		if (err)
+			return err;
 	}
 
 	err = mlx5e_refresh_tirs(priv, true);
 	if (err)
-		return err;
+		goto out;
 
 	lbtp->loopback_ok = false;
 	init_completion(&lbtp->comp);
@@ -256,16 +260,21 @@ static int mlx5e_test_loopback_setup(struct mlx5e_priv *priv,
 	lbtp->pt.dev = priv->netdev;
 	lbtp->pt.af_packet_priv = lbtp;
 	dev_add_pack(&lbtp->pt);
+
+	return 0;
+
+out:
+	if (!lbtp->local_lb)
+		mlx5_nic_vport_update_local_lb(priv->mdev, false);
+
 	return err;
 }
 
 static void mlx5e_test_loopback_cleanup(struct mlx5e_priv *priv,
 					struct mlx5e_lbt_priv *lbtp)
 {
-	if (MLX5_CAP_GEN(priv->mdev, disable_local_lb)) {
 	if (!lbtp->local_lb)
 		mlx5_nic_vport_update_local_lb(priv->mdev, false);
-	}
 
 	dev_remove_pack(&lbtp->pt);
 	mlx5e_refresh_tirs(priv, false);

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

@@ -578,8 +578,7 @@ static int mlx5_core_set_hca_defaults(struct mlx5_core_dev *dev)
 	int ret = 0;
 
 	/* Disable local_lb by default */
-	if ((MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_ETH) &&
-	    MLX5_CAP_GEN(dev, disable_local_lb))
+	if (MLX5_CAP_GEN(dev, port_type) == MLX5_CAP_PORT_TYPE_ETH)
 		ret = mlx5_nic_vport_update_local_lb(dev, false);
 
 	return ret;

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

@@ -908,23 +908,33 @@ int mlx5_nic_vport_update_local_lb(struct mlx5_core_dev *mdev, bool enable)
 	void *in;
 	int err;
 
-	mlx5_core_dbg(mdev, "%s local_lb\n", enable ? "enable" : "disable");
+	if (!MLX5_CAP_GEN(mdev, disable_local_lb_mc) &&
+	    !MLX5_CAP_GEN(mdev, disable_local_lb_uc))
+		return 0;
+
 	in = kvzalloc(inlen, GFP_KERNEL);
 	if (!in)
 		return -ENOMEM;
 
-	MLX5_SET(modify_nic_vport_context_in, in,
-		 field_select.disable_mc_local_lb, 1);
 	MLX5_SET(modify_nic_vport_context_in, in,
 		 nic_vport_context.disable_mc_local_lb, !enable);
+	MLX5_SET(modify_nic_vport_context_in, in,
+		 nic_vport_context.disable_uc_local_lb, !enable);
 
+	if (MLX5_CAP_GEN(mdev, disable_local_lb_mc))
 		MLX5_SET(modify_nic_vport_context_in, in,
-		 field_select.disable_uc_local_lb, 1);
+			 field_select.disable_mc_local_lb, 1);
+
+	if (MLX5_CAP_GEN(mdev, disable_local_lb_uc))
 		MLX5_SET(modify_nic_vport_context_in, in,
-		 nic_vport_context.disable_uc_local_lb, !enable);
+			 field_select.disable_uc_local_lb, 1);
 
 	err = mlx5_modify_nic_vport_context(mdev, in, inlen);
 
+	if (!err)
+		mlx5_core_dbg(mdev, "%s local_lb\n",
+			      enable ? "enable" : "disable");
+
 	kvfree(in);
 	return err;
 }

include/linux/mlx5/mlx5_ifc.h

@@ -1027,8 +1027,9 @@ struct mlx5_ifc_cmd_hca_cap_bits {
 	u8         log_max_wq_sz[0x5];
 
 	u8         nic_vport_change_event[0x1];
-	u8         disable_local_lb[0x1];
-	u8         reserved_at_3e2[0x9];
+	u8         disable_local_lb_uc[0x1];
+	u8         disable_local_lb_mc[0x1];
+	u8         reserved_at_3e3[0x8];
 	u8         log_max_vlan_list[0x5];
 	u8         reserved_at_3f0[0x3];
 	u8         log_max_current_mc_list[0x5];