Re: [PATCH net-next 05/20] net, ynl: Implement netdev_nl_bind_queue_doit

[Stanislav Fomichev <stfomichev@gmail.com>]

On 09/19, Daniel Borkmann wrote:
> From: David Wei <dw@davidwei.uk>
> 
> Implement netdev_nl_bind_queue_doit() that creates a mapped rxq in a
> virtual netdev and then binds it to a real rxq in a physical netdev
> by setting the peer pointer in netdev_rx_queue.
> 
> Signed-off-by: David Wei <dw@davidwei.uk>
> Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
> ---
>  net/core/netdev-genl.c | 117 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 117 insertions(+)
> 
> diff --git a/net/core/netdev-genl.c b/net/core/netdev-genl.c
> index b0aea27bf84e..ed0ce3dbfc6f 100644
> --- a/net/core/netdev-genl.c
> +++ b/net/core/netdev-genl.c
> @@ -1122,6 +1122,123 @@ int netdev_nl_bind_tx_doit(struct sk_buff *skb, struct genl_info *info)
>  
>  int netdev_nl_bind_queue_doit(struct sk_buff *skb, struct genl_info *info)
>  {
> +	u32 src_ifidx, src_qid, dst_ifidx, dst_qid;
> +	struct netdev_rx_queue *src_rxq, *dst_rxq;
> +	struct net_device *src_dev, *dst_dev;
> +	struct netdev_nl_sock *priv;
> +	struct sk_buff *rsp;
> +	int err = 0;
> +	void *hdr;
> +
> +	if (GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_SRC_IFINDEX) ||
> +	    GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_SRC_QUEUE_ID) ||
> +	    GENL_REQ_ATTR_CHECK(info, NETDEV_A_QUEUE_PAIR_DST_IFINDEX))
> +		return -EINVAL;
> +
> +	src_ifidx = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_SRC_IFINDEX]);
> +	src_qid = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_SRC_QUEUE_ID]);
> +	dst_ifidx = nla_get_u32(info->attrs[NETDEV_A_QUEUE_PAIR_DST_IFINDEX]);
> +	if (dst_ifidx == src_ifidx) {
> +		NL_SET_ERR_MSG(info->extack,
> +			       "Destination driver cannot be same as source driver");
> +		return -EOPNOTSUPP;
> +	}
> +

[..]

> +	priv = genl_sk_priv_get(&netdev_nl_family, NETLINK_CB(skb).sk);
> +	if (IS_ERR(priv))
> +		return PTR_ERR(priv);

Why do you need genl_sk_priv_get and mutex_lock?