Subject: Re: [patch net-next 5/6] switchdev: remove FIB offload infrastructure

From: Ido Schimmel <[email-masked]>
Date: Thu, 22 Sep 2016 10:25:19 +0300

On Wed, Sep 21, 2016 at 01:53:13PM +0200, Jiri Pirko wrote:
> From: Jiri Pirko <[email-masked]>
> 
> Since this is now taken care of by FIB notifier, remove the code, with
> all unused dependencies.
> 
> Signed-off-by: Jiri Pirko <[email-masked]>

[...]

> -static struct net_device *switchdev_get_dev_by_nhs(struct fib_info *fi)
> -{
> -	struct switchdev_attr attr = {
> -		.id = SWITCHDEV_ATTR_ID_PORT_PARENT_ID,
> -	};
> -	struct switchdev_attr prev_attr;
> -	struct net_device *dev = NULL;
> -	int nhsel;
> -
> -	ASSERT_RTNL();
> -
> -	/* For this route, all nexthop devs must be on the same switch. */
> -
> -	for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
> -		const struct fib_nh *nh = &fi->fib_nh[nhsel];
> -
> -		if (!nh->nh_dev)
> -			return NULL;
> -
> -		dev = switchdev_get_lowest_dev(nh->nh_dev);
> -		if (!dev)
> -			return NULL;
> -
> -		attr.orig_dev = dev;
> -		if (switchdev_port_attr_get(dev, &attr))
> -			return NULL;
> -
> -		if (nhsel > 0 &&
> -		    !netdev_phys_item_id_same(&prev_attr.u.ppid, &attr.u.ppid))
> -				return NULL;
> -
> -		prev_attr = attr;
> -	}
> -
> -	return dev;
> -}

[...]

> -int switchdev_fib_ipv4_add(u32 dst, int dst_len, struct fib_info *fi,
> -			   u8 tos, u8 type, u32 nlflags, u32 tb_id)
> -{
> -	struct switchdev_obj_ipv4_fib ipv4_fib = {
> -		.obj.id = SWITCHDEV_OBJ_ID_IPV4_FIB,
> -		.dst = dst,
> -		.dst_len = dst_len,
> -		.fi = fi,
> -		.tos = tos,
> -		.type = type,
> -		.nlflags = nlflags,
> -		.tb_id = tb_id,
> -	};
> -	struct net_device *dev;
> -	int err = 0;
> -
> -	/* Don't offload route if using custom ip rules or if
> -	 * IPv4 FIB offloading has been disabled completely.
> -	 */
> -
> -#ifdef CONFIG_IP_MULTIPLE_TABLES
> -	if (fi->fib_net->ipv4.fib_has_custom_rules)
> -		return 0;
> -#endif
> -
> -	if (fi->fib_net->ipv4.fib_offload_disabled)
> -		return 0;
> -
> -	dev = switchdev_get_dev_by_nhs(fi);

Since this is now removed I believe we should perform this check inside
the drivers. For mlxsw we can simply iterate over the nexthops and make
sure each has a RIF.

> -	if (!dev)
> -		return 0;
> -
> -	ipv4_fib.obj.orig_dev = dev;
> -	err = switchdev_port_obj_add(dev, &ipv4_fib.obj);
> -	if (!err)
> -		fib_info_offload_inc(fi);
> -
> -	return err == -EOPNOTSUPP ? 0 : err;
> -}