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

[Moshe Shemesh <moshe@nvidia.com>]

On 9/15/2020 12:33 AM, Jakub Kicinski wrote:
> External email: Use caution opening links or attachments
>
>
> 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).


OK, I can do that. But I update stats and generate devlink notification 
anyway, that should fine, right ?