Re: [PATCH 4/5] net/mlx5: use Netlink to enable promisc/allmulti

[Adrien Mazarguil <adrien.mazarguil@6wind.com>]

On Tue, Mar 13, 2018 at 01:50:38PM +0100, Nelio Laranjeiro wrote:
> VF devices are not able to receive promisc or allmulti traffic unless it
> fully requests it though Netlink.  This will cause the request to be
> processed by the PF which will handle the request and enable it.
> 
> This requires the VF to be trusted by the PF.
> 
> Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>

Usual comments regarding "vf" => "nl", caps and typos. More nits below.

> ---
>  drivers/net/mlx5/mlx5.h         |   2 +
>  drivers/net/mlx5/mlx5_trigger.c |  27 ++++++++++-
>  drivers/net/mlx5/mlx5_vf.c      | 102 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 130 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
> index a4333e6a5..245235641 100644
> --- a/drivers/net/mlx5/mlx5.h
> +++ b/drivers/net/mlx5/mlx5.h
> @@ -303,5 +303,7 @@ int mlx5_mr_verify(struct rte_eth_dev *dev);
>  int mlx5_vf_mac_addr_add(struct rte_eth_dev *dev, struct ether_addr *mac);
>  int mlx5_vf_mac_addr_remove(struct rte_eth_dev *dev, struct ether_addr *mac);
>  int mlx5_vf_mac_addr_flush(struct rte_eth_dev *dev);
> +int mlx5_vf_promisc(struct rte_eth_dev *dev, int enable);
> +int mlx5_vf_allmulti(struct rte_eth_dev *dev, int enable);
>  
>  #endif /* RTE_PMD_MLX5_H_ */
> diff --git a/drivers/net/mlx5/mlx5_trigger.c b/drivers/net/mlx5/mlx5_trigger.c
> index 6bb4ffb14..3f21797ff 100644
> --- a/drivers/net/mlx5/mlx5_trigger.c
> +++ b/drivers/net/mlx5/mlx5_trigger.c
> @@ -278,8 +278,23 @@ mlx5_traffic_enable(struct rte_eth_dev *dev)
>  	unsigned int j;
>  	int ret;
>  
> -	if (priv->isolated)
> +	if (priv->isolated) {
> +		if (priv->config.vf) {
> +			if (dev->data->promiscuous) {
> +				ret = mlx5_vf_promisc(dev, 1);
> +				rte_errno = ret;
> +				if (ret)
> +					goto error;
> +			}
> +			if (dev->data->all_multicast) {
> +				ret = mlx5_vf_allmulti(dev, 1);
> +				rte_errno = ret;
> +				if (ret)
> +					goto error;
> +			}
> +		}

Looks like this block should be run no matter what. You should put it before
the check on priv->isolated and drop the two next chunks.

Note there seems to be missing rollback code in case of error.

>  		return 0;
> +	}
>  	if (dev->data->promiscuous) {
>  		struct rte_flow_item_eth promisc = {
>  			.dst.addr_bytes = "\x00\x00\x00\x00\x00\x00",
> @@ -287,6 +302,11 @@ mlx5_traffic_enable(struct rte_eth_dev *dev)
>  			.type = 0,
>  		};
>  
> +		if (priv->config.vf) {
> +			ret = mlx5_vf_promisc(dev, 1);
> +			if (ret)
> +				goto error;
> +		}
>  		ret = mlx5_ctrl_flow(dev, &promisc, &promisc);
>  		if (ret)
>  			goto error;
> @@ -298,6 +318,11 @@ mlx5_traffic_enable(struct rte_eth_dev *dev)
>  			.type = 0,
>  		};
>  
> +		if (priv->config.vf) {
> +			ret = mlx5_vf_allmulti(dev, 1);
> +			if (ret)
> +				goto error;
> +		}
>  		ret = mlx5_ctrl_flow(dev, &multicast, &multicast);
>  		if (ret)
>  			goto error;
> diff --git a/drivers/net/mlx5/mlx5_vf.c b/drivers/net/mlx5/mlx5_vf.c
> index 3db8ee0eb..cf71e79d9 100644
> --- a/drivers/net/mlx5/mlx5_vf.c
> +++ b/drivers/net/mlx5/mlx5_vf.c
> @@ -447,3 +447,105 @@ mlx5_vf_mac_addr_flush(struct rte_eth_dev *dev)
>  	}
>  	return 0;
>  }
> +
> +/**
> + * Enable promisc/allmulti though Netlink

though => through, also missing period.

I suggest to write promisc and allmulti in full in documentation
(as "promiscuous" and "all multicast" modes).

> + *
> + * @param dev
> + *   Pointer to Ethernet device structure.
> + * @param flags
> + *   IFF_PROMISC for promiscuous, IFF_ALLMULTI for allmulti.
> + * @param en

en => enable

> + *   1 to enable, 0 to disable.

=> Nonzero to enable, disable otherwise.

> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +static int
> +mlx5_vf_device_flags(struct rte_eth_dev *dev, uint32_t flags, int enable)
> +{
> +	int iface_idx = mlx5_vf_iface_idx(dev);
> +	struct {
> +		struct nlmsghdr hdr;
> +		struct ifinfomsg ifi;
> +	} req = {
> +		.hdr = {
> +			.nlmsg_len = NLMSG_LENGTH(sizeof(struct ifinfomsg)),
> +			.nlmsg_type = RTM_NEWLINK,
> +			.nlmsg_flags = NLM_F_REQUEST,
> +		},
> +		.ifi = {
> +			.ifi_flags = enable ? flags : 0,
> +			.ifi_change = flags,
> +			.ifi_index = iface_idx,
> +		},
> +	};
> +	int fd;
> +	int ret;
> +
> +	assert(!(flags & ~(IFF_PROMISC | IFF_ALLMULTI)));
> +	fd = rte_nl_init(NETLINK_ROUTE);
> +	if (fd < 0) {
> +		rte_errno = errno;
> +		goto error;
> +	}
> +	ret = rte_nl_send(fd, &req.hdr);
> +	if (ret == -1) {
> +		rte_errno = errno;
> +		goto error;
> +	}
> +	rte_nl_final(fd);
> +	return 0;
> +error:
> +	if (fd >= 0)
> +		rte_nl_final(fd);
> +	return -rte_errno;
> +}
> +
> +/**
> + * Enable promisc though Netlink

Missing period, another suggestion: promisc => promiscuous mode.

> + *
> + * @param dev
> + *   Pointer to Ethernet device structure.
> + * @param en
> + *   1 to enable promisc, 0 to disable it.

=> Nonzero to enable, disable otherwise.

> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +int
> +mlx5_vf_promisc(struct rte_eth_dev *dev, int enable)
> +{
> +	int ret = mlx5_vf_device_flags(dev, IFF_PROMISC, enable);
> +
> +	if (ret)
> +		DRV_LOG(DEBUG,
> +			"port %u cannot %s promisc mode: Netlink error %s",
> +			dev->data->port_id, enable ? "enable" : "disable",
> +			strerror(rte_errno));
> +	return ret;
> +}
> +
> +/**
> + * Enable allmulti though Netlink

though => through

> + *
> + * @param dev
> + *   Pointer to Ethernet device structure.
> + * @param en
> + *   1 to enable promisc, 0 to disable it.
> + *
> + * @return
> + *   0 on success, a negative errno value otherwise and rte_errno is set.
> + */
> +int
> +mlx5_vf_allmulti(struct rte_eth_dev *dev, int enable)
> +{
> +	int ret = mlx5_vf_device_flags(dev, IFF_ALLMULTI, enable);
> +
> +	if (ret)
> +		DRV_LOG(DEBUG,
> +			"port %u cannot %s allmulti mode: Netlink error %s",
> +			dev->data->port_id, enable ? "enable" : "disable",
> +			strerror(rte_errno));
> +	return ret;
> +}
> -- 
> 2.11.0
> 

-- 
Adrien Mazarguil
6WIND