Subject: Re: [PATCH v2 net-next 02/12] net: ethtool: add support for MAC Merge layer

From: Jakub Kicinski <[email-masked]>
Date: Thu, 12 Jan 2023 22:27:04 -0800

On Wed, 11 Jan 2023 18:16:56 +0200 Vladimir Oltean wrote:
> +/**
> + * enum ethtool_mm_verify_status - status of MAC Merge Verify function
> + * @ETHTOOL_MM_VERIFY_STATUS_UNKNOWN:
> + *	verification status is unknown
> + * @ETHTOOL_MM_VERIFY_STATUS_INITIAL:
> + *	the 802.3 Verify State diagram is in the state INIT_VERIFICATION
> + * @ETHTOOL_MM_VERIFY_STATUS_VERIFYING:
> + *	the Verify State diagram is in the state VERIFICATION_IDLE,

funky characters here

> + *	SEND_VERIFY or WAIT_FOR_RESPONSE
> + * @ETHTOOL_MM_VERIFY_STATUS_SUCCEEDED:
> + *	indicates that the Verify State diagram is in the state VERIFIED
> + * @ETHTOOL_MM_VERIFY_STATUS_FAILED:
> + *	the Verify State diagram is in the state VERIFY_FAIL
> + * @ETHTOOL_MM_VERIFY_STATUS_DISABLED:
> + *	verification of preemption operation is disabled
> + */

> +static int mm_prepare_data(const struct ethnl_req_info *req_base,
> +			   struct ethnl_reply_data *reply_base,
> +			   struct genl_info *info)
> +{
> +	struct mm_reply_data *data = MM_REPDATA(reply_base);
> +	struct net_device *dev = reply_base->dev;
> +	const struct ethtool_ops *ops;
> +	int ret;
> +
> +	ops = dev->ethtool_ops;
> +
> +	if (!ops->get_mm)
> +		return -EOPNOTSUPP;
> +
> +	ethtool_stats_init((u64 *)&data->stats,
> +			   sizeof(data->stats) / sizeof(u64));
> +
> +	ret = ethnl_ops_begin(dev);
> +	if (ret < 0)

nit: in set you do if (ret) after begin

> +		return ret;
> +
> +	ops->get_mm(dev, &data->state);
> +
> +	if (ops->get_mm_stats && (req_base->flags & ETHTOOL_FLAG_STATS))
> +		ops->get_mm_stats(dev, &data->stats);
> +
> +	ethnl_ops_complete(dev);
> +
> +	return 0;
> +}

> +int ethnl_set_mm(struct sk_buff *skb, struct genl_info *info)
> +{
> +	struct netlink_ext_ack *extack = info->extack;
> +	struct ethnl_req_info req_info = {};
> +	struct ethtool_mm_state state = {};
> +	struct nlattr **tb = info->attrs;
> +	struct ethtool_mm_cfg cfg = {};
> +	const struct ethtool_ops *ops;
> +	struct net_device *dev;
> +	bool mod = false;
> +	int ret;
> +
> +	ret = ethnl_parse_header_dev_get(&req_info, tb[ETHTOOL_A_MM_HEADER],
> +					 genl_info_net(info), extack, true);
> +	if (ret)
> +		return ret;
> +
> +	dev = req_info.dev;
> +	ops = dev->ethtool_ops;
> +
> +	if (!ops->get_mm || !ops->set_mm) {
> +		ret = -EOPNOTSUPP;
> +		goto out_dev;
> +	}
> +
> +	rtnl_lock();
> +	ret = ethnl_ops_begin(dev);
> +	if (ret)
> +		goto out_rtnl;
> +
> +	ops->get_mm(dev, &state);
> +
> +	mm_state_to_cfg(&state, &cfg);
> +
> +	if (cfg.verify_time > state.max_verify_time) {
> +		NL_SET_ERR_MSG_MOD(extack, "verifyTime exceeds device maximum");

Drop the _MOD() add _ATTR()

> +		return -ERANGE;

goto out_ops;

> +	}
> +
> +	ethnl_update_bool(&cfg.verify_enabled, tb[ETHTOOL_A_MM_VERIFY_ENABLED],
> +			  &mod);
> +	ethnl_update_u32(&cfg.verify_time, tb[ETHTOOL_A_MM_VERIFY_TIME], &mod);
> +	ethnl_update_bool(&cfg.tx_enabled, tb[ETHTOOL_A_MM_TX_ENABLED], &mod);
> +	ethnl_update_bool(&cfg.pmac_enabled, tb[ETHTOOL_A_MM_PMAC_ENABLED],
> +			  &mod);
> +	ethnl_update_u32(&cfg.add_frag_size, tb[ETHTOOL_A_MM_ADD_FRAG_SIZE],
> +			 &mod);

you never use the @mod?

> +	ret = ops->set_mm(dev, &cfg, extack);
> +	if (ret) {
> +		if (!extack->_msg)
> +			NL_SET_ERR_MSG(extack,
> +				       "Failed to update MAC merge configuration");

Why add this extack? It's it evident that the config wasn't updated
from the fact the netlink ACK carries a non-zero error?

> +		goto out_ops;
> +	}
> +
> +	ethtool_notify(dev, ETHTOOL_MSG_MM_NTF, NULL);
> +
> +out_ops:
> +	ethnl_ops_complete(dev);
> +out_rtnl:
> +	rtnl_unlock();
> +out_dev:
> +	dev_put(dev);

ethnl_parse_header_dev_put()

> +	return ret;
> +}

I'm out of time for the day, feel free to send v3, or I'll just pick up
here tomorrow.