Re: [PATCH] nfp: add basic multicast filtering

[Simon Horman <simon.horman@netronome.com>]

On Thu, Jan 04, 2018 at 04:10:19PM +0100, Simon Horman wrote:
> From: Jakub Kicinski <jakub.kicinski@netronome.com>
> 
> We currently always pass all multicast traffic through.
> Only set L2MC when actually needed.  Since the driver
> was not making use of the capability to filter out mcast
> frames, some FW projects don't implement it any more.
> Don't warn users if capability is not present (like we
> do for promisc flag).  The lack of L2MC capability is
> assumed to mean all multicast traffic goes through.
> 
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> Signed-off-by: Simon Horman <simon.horman@netronome.com>

Apologies, I somehow forgot to mark this as being for net-next.

> ---
>  drivers/net/ethernet/netronome/nfp/nfp_net_common.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> index 0add4870ce2e..29c0947f6d70 100644
> --- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
> @@ -2850,6 +2850,11 @@ static void nfp_net_set_rx_mode(struct net_device *netdev)
>  
>  	new_ctrl = nn->dp.ctrl;
>  
> +	if (!netdev_mc_empty(netdev) || netdev->flags & IFF_ALLMULTI)
> +		new_ctrl |= nn->cap & NFP_NET_CFG_CTRL_L2MC;
> +	else
> +		new_ctrl &= ~NFP_NET_CFG_CTRL_L2MC;
> +
>  	if (netdev->flags & IFF_PROMISC) {
>  		if (nn->cap & NFP_NET_CFG_CTRL_PROMISC)
>  			new_ctrl |= NFP_NET_CFG_CTRL_PROMISC;
> @@ -3787,8 +3792,6 @@ int nfp_net_init(struct nfp_net *nn)
>  	/* Allow L2 Broadcast and Multicast through by default, if supported */
>  	if (nn->cap & NFP_NET_CFG_CTRL_L2BC)
>  		nn->dp.ctrl |= NFP_NET_CFG_CTRL_L2BC;
> -	if (nn->cap & NFP_NET_CFG_CTRL_L2MC)
> -		nn->dp.ctrl |= NFP_NET_CFG_CTRL_L2MC;
>  
>  	/* Allow IRQ moderation, if supported */
>  	if (nn->cap & NFP_NET_CFG_CTRL_IRQMOD) {
> -- 
> 2.11.0
>