[net-next,v3,1/3] net: dsa: add support for bridge flags

The Linux bridge implementation allows various properties of the bridge
to be controlled, such as flooding unknown unicast and multicast frames.
This patch adds the necessary DSA infrastructure to allow the Linux
bridge support to control these properties for DSA switches.

We implement this by providing two new methods: one to get the switch-
wide support bitmask, and another to set the properties.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 include/net/dsa.h  |  2 ++
 net/dsa/dsa_priv.h |  2 ++
 net/dsa/port.c     | 16 ++++++++++++++++
 net/dsa/slave.c    |  6 ++++++
 4 files changed, 26 insertions(+)

Hi Russell,

On Wed, 20 Feb 2019 12:36:48 +0000, Russell King <rmk+kernel@armlinux.org.uk> wrote:
> The Linux bridge implementation allows various properties of the bridge
> to be controlled, such as flooding unknown unicast and multicast frames.
> This patch adds the necessary DSA infrastructure to allow the Linux
> bridge support to control these properties for DSA switches.
> 
> We implement this by providing two new methods: one to get the switch-
> wide support bitmask, and another to set the properties.

This is not true anymore ;-)

> 
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
> ---
>  include/net/dsa.h  |  2 ++
>  net/dsa/dsa_priv.h |  2 ++
>  net/dsa/port.c     | 16 ++++++++++++++++
>  net/dsa/slave.c    |  6 ++++++
>  4 files changed, 26 insertions(+)
> 
> diff --git a/include/net/dsa.h b/include/net/dsa.h
> index 7f2a668ef2cc..2c2c10812814 100644
> --- a/include/net/dsa.h
> +++ b/include/net/dsa.h
> @@ -400,6 +400,8 @@ struct dsa_switch_ops {
>  	void	(*port_stp_state_set)(struct dsa_switch *ds, int port,
>  				      u8 state);
>  	void	(*port_fast_age)(struct dsa_switch *ds, int port);
> +	int	(*port_egress_floods)(struct dsa_switch *ds, int port,
> +				      bool unicast, bool multicast);
>  
>  	/*
>  	 * VLAN support
> diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
> index 1f4972dab9f2..f4f99ec29f5d 100644
> --- a/net/dsa/dsa_priv.h
> +++ b/net/dsa/dsa_priv.h
> @@ -160,6 +160,8 @@ int dsa_port_mdb_add(const struct dsa_port *dp,
>  		     struct switchdev_trans *trans);
>  int dsa_port_mdb_del(const struct dsa_port *dp,
>  		     const struct switchdev_obj_port_mdb *mdb);
> +int dsa_port_bridge_flags(const struct dsa_port *dp, unsigned long flags,
> +			  struct switchdev_trans *trans);
>  int dsa_port_vlan_add(struct dsa_port *dp,
>  		      const struct switchdev_obj_port_vlan *vlan,
>  		      struct switchdev_trans *trans);
> diff --git a/net/dsa/port.c b/net/dsa/port.c
> index 2d7e01b23572..b84d010fb165 100644
> --- a/net/dsa/port.c
> +++ b/net/dsa/port.c
> @@ -177,6 +177,22 @@ int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock,
>  	return dsa_port_notify(dp, DSA_NOTIFIER_AGEING_TIME, &info);
>  }
>  
> +int dsa_port_bridge_flags(const struct dsa_port *dp, unsigned long flags,
> +			  struct switchdev_trans *trans)
> +{
> +	struct dsa_switch *ds = dp->ds;
> +	int port = dp->index;
> +
> +	if (switchdev_trans_ph_prepare(trans))
> +		return 0;
> +
> +	if (ds->ops->port_egress_floods)
> +		ds->ops->port_egress_floods(ds, port, flags & BR_FLOOD,
> +					    flags & BR_MCAST_FLOOD);

Even though we're not supposed to fail in the switchdev commit phase, I'd
prefer not to ignore the return code.

> +
> +	return 0;
> +}
> +
>  int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr,
>  		     u16 vid)
>  {
> diff --git a/net/dsa/slave.c b/net/dsa/slave.c
> index 2e5e7c04821b..f99161c3b1ea 100644
> --- a/net/dsa/slave.c
> +++ b/net/dsa/slave.c
> @@ -295,6 +295,9 @@ static int dsa_slave_port_attr_set(struct net_device *dev,
>  	case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
>  		ret = dsa_port_ageing_time(dp, attr->u.ageing_time, trans);
>  		break;
> +	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS:
> +		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags, trans);
> +		break;
>  	default:
>  		ret = -EOPNOTSUPP;
>  		break;
> @@ -384,6 +387,9 @@ static int dsa_slave_port_attr_get(struct net_device *dev,
>  	switch (attr->id) {
>  	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS_SUPPORT:
>  		attr->u.brport_flags_support = 0;
> +		if (ds->ops->port_egress_floods)
> +			attr->u.brport_flags_support |= BR_FLOOD |
> +							BR_MCAST_FLOOD;
>  		break;
>  	default:
>  		return -EOPNOTSUPP;

Otherwise, LGTM:

Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>