Re: [PATCH net-next RFC v4 01/15] devlink: Add reload action option to devlink reload command

Jakub Kicinski
2020-09-14T21:33:23Z

On Mon, 14 Sep 2020 09:07:48 +0300 Moshe Shemesh wrote:
> @@ -3011,12 +3060,41 @@ static int devlink_nl_cmd_reload(struct sk_buff *skb, struct genl_info *info)
> return PTR_ERR(dest_net);
> }
>
> - err = devlink_reload(devlink, dest_net, info->extack);
> + if (info->attrs[DEVLINK_ATTR_RELOAD_ACTION])
> + action = nla_get_u8(info->attrs[DEVLINK_ATTR_RELOAD_ACTION]);
> + else
> + action = DEVLINK_RELOAD_ACTION_DRIVER_REINIT;
> +
> + if (action == DEVLINK_RELOAD_ACTION_UNSPEC || action > DEVLINK_RELOAD_ACTION_MAX) {
> + NL_SET_ERR_MSG_MOD(info->extack, "Invalid reload action");
> + return -EINVAL;
> + } else if (!devlink_reload_action_is_supported(devlink, action)) {
> + NL_SET_ERR_MSG_MOD(info->extack, "Requested reload action is not supported");
> + return -EOPNOTSUPP;
> + }
> +
> + err = devlink_reload(devlink, dest_net, action, info->extack, &actions_performed);
>
> if (dest_net)
> put_net(dest_net);
>
> - return err;
> + if (err)
> + return err;
> +
> + WARN_ON(!actions_performed);
> + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
> + if (!msg)
> + return -ENOMEM;
> +
> + err = devlink_nl_reload_actions_performed_fill(msg, devlink, actions_performed,
> + DEVLINK_CMD_RELOAD, info->snd_portid,
> + info->snd_seq, 0);
> + if (err) {
> + nlmsg_free(msg);
> + return err;
> + }
> +
> + return genlmsg_reply(msg, info);

I think generating the reply may break existing users. Only generate
the reply if request contained DEVLINK_ATTR_RELOAD_ACTION (or any other
new attribute which existing users can't pass).