RE: [RFC PATCH net-next v2 1/1] net: Support for switch port configuration

["Varlese, Marco" <marco.varlese@intel.com>]

> -----Original Message-----
> From: Roopa Prabhu [mailto:roopa@cumulusnetworks.com]
> Sent: Thursday, December 18, 2014 2:45 PM
> To: Varlese, Marco
> Cc: netdev@vger.kernel.org; Fastabend, John R; Thomas Graf; Jiri Pirko;
> sfeldma@gmail.com; linux-kernel@vger.kernel.org
> Subject: Re: [RFC PATCH net-next v2 1/1] net: Support for switch port
> configuration
> 
> On 12/18/14, 3:29 AM, Varlese, Marco wrote:
> > From: Marco Varlese <marco.varlese@intel.com>
> >
> > Switch hardware offers a list of attributes that are configurable on a
> > per port basis.
> > This patch provides a mechanism to configure switch ports by adding an
> > NDO for setting specific values to specific attributes.
> > There will be a separate patch that adds the "get" functionality via
> > another NDO and another patch that extends iproute2 to call the two
> > new NDOs.
> >
> > Signed-off-by: Marco Varlese <marco.varlese@intel.com>
> > ---
> >   include/linux/netdevice.h    |  5 ++++
> >   include/uapi/linux/if_link.h | 15 ++++++++++++
> >   net/core/rtnetlink.c         | 54
> ++++++++++++++++++++++++++++++++++++++++++++
> >   3 files changed, 74 insertions(+)
> >
> > diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> > index c31f74d..4881c7b 100644
> > --- a/include/linux/netdevice.h
> > +++ b/include/linux/netdevice.h
> > @@ -1027,6 +1027,9 @@ typedef u16 (*select_queue_fallback_t)(struct
> net_device *dev,
> >    * int (*ndo_switch_port_stp_update)(struct net_device *dev, u8 state);
> >    *	Called to notify switch device port of bridge port STP
> >    *	state change.
> > + * int (*ndo_switch_port_set_cfg)(struct net_device *dev,
> > + *                                u32 attr, u64 value);
> > + *	Called to set specific switch ports attributes.
> >    */
> >   struct net_device_ops {
> >   	int			(*ndo_init)(struct net_device *dev);
> > @@ -1185,6 +1188,8 @@ struct net_device_ops {
> >   							    struct
> netdev_phys_item_id *psid);
> >   	int			(*ndo_switch_port_stp_update)(struct
> net_device *dev,
> >   							      u8 state);
> > +	int			(*ndo_switch_port_set_cfg)(struct
> net_device *dev,
> > +							   u32 attr, u64 value);
> >   #endif
> >   };
> >
> > diff --git a/include/uapi/linux/if_link.h
> > b/include/uapi/linux/if_link.h index f7d0d2d..19cb51a 100644
> > --- a/include/uapi/linux/if_link.h
> > +++ b/include/uapi/linux/if_link.h
> > @@ -146,6 +146,7 @@ enum {
> >   	IFLA_PHYS_PORT_ID,
> >   	IFLA_CARRIER_CHANGES,
> >   	IFLA_PHYS_SWITCH_ID,
> > +	IFLA_SWITCH_PORT_CFG,
> >   	__IFLA_MAX
> >   };
> >
> > @@ -603,4 +604,18 @@ enum {
> >
> >   #define IFLA_HSR_MAX (__IFLA_HSR_MAX - 1)
> >
> > +/* Switch Port Attributes section */
> > +
> > +enum {
> > +	IFLA_ATTR_UNSPEC,
> > +	IFLA_ATTR_LEARNING,
> Any reason you want learning here ?. This is covered as part  of the bridge
> setlink attributes.
> 

Yes, because the user may _not_ want to go through a bridge interface necessarily. 

> > +	IFLA_ATTR_LOOPBACK,
> > +	IFLA_ATTR_BCAST_FLOODING,
> > +	IFLA_ATTR_UCAST_FLOODING,
> > +	IFLA_ATTR_MCAST_FLOODING,
> > +	__IFLA_ATTR_MAX
> > +};
> > +
> > +#define IFLA_ATTR_MAX (__IFLA_ATTR_MAX - 1)
> > +
> >   #endif /* _UAPI_LINUX_IF_LINK_H */
> > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index
> > eaa057f..c0d1c45 100644
> > --- a/net/core/rtnetlink.c
> > +++ b/net/core/rtnetlink.c
> > @@ -1389,6 +1389,46 @@ static int validate_linkmsg(struct net_device
> *dev, struct nlattr *tb[])
> >   	return 0;
> >   }
> >
> > +#ifdef CONFIG_NET_SWITCHDEV
> > +static int do_setswcfg(struct net_device *dev, struct nlattr *attr) {
> > +	int rem, err = -EINVAL;
> > +	struct nlattr *v;
> > +	const struct net_device_ops *ops = dev->netdev_ops;
> > +
> > +	nla_for_each_nested(v, attr, rem) {
> > +		u32 op = nla_type(v);
> > +		u64 value = 0;
> > +
> > +		switch (op) {
> > +		case IFLA_ATTR_LEARNING:
> > +		case IFLA_ATTR_LOOPBACK:
> > +		case IFLA_ATTR_BCAST_FLOODING:
> > +		case IFLA_ATTR_UCAST_FLOODING:
> > +		case IFLA_ATTR_MCAST_FLOODING: {
> > +			if (nla_len(v) < sizeof(value)) {
> > +				err = -EINVAL;
> > +				break;
> > +			}
> > +
> > +			value = nla_get_u64(v);
> > +			err = ops->ndo_switch_port_set_cfg(dev,
> > +							   op,
> > +							   value);
> > +			break;
> > +		}
> > +		default:
> > +			err = -EINVAL;
> > +			break;
> > +		}
> > +		if (err)
> > +			break;
> > +	}
> > +	return err;
> > +}
> > +
> > +#endif
> > +
> >   static int do_setvfinfo(struct net_device *dev, struct nlattr *attr)
> >   {
> >   	int rem, err = -EINVAL;
> > @@ -1740,6 +1780,20 @@ static int do_setlink(const struct sk_buff *skb,
> >   			status |= DO_SETLINK_NOTIFY;
> >   		}
> >   	}
> > +#ifdef CONFIG_NET_SWITCHDEV
> > +	if (tb[IFLA_SWITCH_PORT_CFG]) {
> > +		err = -EOPNOTSUPP;
> > +		if (!ops->ndo_switch_port_set_cfg)
> > +			goto errout;
> > +		if (!ops->ndo_switch_parent_id_get)
> > +			goto errout;
> > +		err = do_setswcfg(dev, tb[IFLA_SWITCH_PORT_CFG]);
> > +		if (err < 0)
> > +			goto errout;
> > +
> > +		status |= DO_SETLINK_NOTIFY;
> > +	}
> > +#endif
> >   	err = 0;
> >
> >   errout: