devlink: Hold the instance lock in port_new / port_del callbacks

Let the core take the devlink instance lock around port_new and port_del
callbacks and remove the now redundant locking in the only driver that
currently use them.
Signed-off-by: Moshe Shemesh <moshe@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

drivers/net/ethernet/mellanox/mlx5/core/sf/devlink.c

@@ -355,9 +355,7 @@ int mlx5_devlink_sf_port_new(struct devlink *devlink,
 				   "Port add is only supported in eswitch switchdev mode or SF ports are disabled.");
 		return -EOPNOTSUPP;
 	}
-	devl_lock(devlink);
 	err = mlx5_sf_add(dev, table, new_attr, extack, new_port_index);
-	devl_unlock(devlink);
 	mlx5_sf_table_put(table);
 	return err;
 }
@@ -402,9 +400,7 @@ int mlx5_devlink_sf_port_del(struct devlink *devlink, unsigned int port_index,
 		goto sf_err;
 	}
 
-	devl_lock(devlink);
 	mlx5_esw_offloads_sf_vport_disable(esw, sf->hw_fn_id);
-	devl_unlock(devlink);
 	mlx5_sf_id_erase(table, sf);
 
 	mutex_lock(&table->sf_state_lock);

net/core/devlink.c

@@ -1712,7 +1712,7 @@ static int devlink_port_new_notifiy(struct devlink *devlink,
 	if (!msg)
 		return -ENOMEM;
 
-	mutex_lock(&devlink->lock);
+	lockdep_assert_held(&devlink->lock);
 	devlink_port = devlink_port_get_by_index(devlink, port_index);
 	if (!devlink_port) {
 		err = -ENODEV;
@@ -1725,11 +1725,9 @@ static int devlink_port_new_notifiy(struct devlink *devlink,
 		goto out;
 
 	err = genlmsg_reply(msg, info);
-	mutex_unlock(&devlink->lock);
 	return err;
 
 out:
-	mutex_unlock(&devlink->lock);
 	nlmsg_free(msg);
 	return err;
 }
@@ -9067,13 +9065,11 @@ static const struct genl_small_ops devlink_nl_ops[] = {
 		.cmd = DEVLINK_CMD_PORT_NEW,
 		.doit = devlink_nl_cmd_port_new_doit,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
 		.cmd = DEVLINK_CMD_PORT_DEL,
 		.doit = devlink_nl_cmd_port_del_doit,
 		.flags = GENL_ADMIN_PERM,
-		.internal_flags = DEVLINK_NL_FLAG_NO_LOCK,
 	},
 	{
 		.cmd = DEVLINK_CMD_LINECARD_GET,