Re: [B.A.T.M.A.N.] [PATCH 1/3] batman-adv: detect clients connected through a 802.11 device

[Marek Lindner <lindner_marek@yahoo.de>]

On Sunday, June 05, 2011 11:01:02 PM Antonio Quartulli wrote:
> +/* This function returns true if the interface represented by ifindex is a
> + * 802.11 wireless device */
> +bool is_wifi_iface(int ifindex)
> +{
> +       struct net_device *net_device;
> +
> +       if (ifindex == NULL_IFINDEX)
> +               return false;
> +
> +       net_device = dev_get_by_index(&init_net, ifindex);
> +       if (!net_device)
> +               return false;
> +
> +#ifdef CONFIG_WIRELESS_EXT
> +       /* pre-cfg80211 drivers have to implement WEXT, so it is possible to
> +        * check for wireless_handlers != NULL */
> +       if (net_device->wireless_handlers)
> +               return true;
> +       else
> +#endif
> +               /* cfg80211 drivers have to set ieee80211_ptr */
> +               if (net_device->ieee80211_ptr)
> +                       return true;
> +       return false;
> +}

If I am not mistaken dev_get_by_index() increases a counter on the returned 
interface. We have to decrease that counter as soon as we don't need the 
interface anymore otherwise the interface can never be freed.


> @@ -108,7 +108,7 @@ int mesh_init(struct net_device *soft_iface)
>  	if (tt_init(bat_priv) < 1)
>  		goto err;
> 
> -	tt_local_add(soft_iface, soft_iface->dev_addr);
> +	tt_local_add(soft_iface, soft_iface->dev_addr, NULL_IFINDEX);

Are you sure 0 is not a valid index for any interface ?


>  static void tt_local_event(struct bat_priv *bat_priv, uint8_t op,
> -			   const uint8_t *addr, bool roaming)
> +			   const uint8_t *addr, bool roaming, bool wifi)

How about adding a set of flags (TT_CLIENT_ROAM / TT_CLIENT_WIFI / etc) 
instead of adding more and more bool arguments ? In several places the code 
converts one to the other which does not seem necessary.


> +void tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
> +		  int ifindex)
>  {
>  	struct bat_priv *bat_priv = netdev_priv(soft_iface);
>  	struct tt_local_entry *tt_local_entry = NULL;
> @@ -204,21 +231,22 @@ void tt_local_add(struct net_device *soft_iface,
> const uint8_t *addr) if (!tt_local_entry)
>  		goto out;
> 
> -	tt_local_event(bat_priv, NO_FLAGS, addr, false);
> -
>  	bat_dbg(DBG_TT, bat_priv,
>  		"Creating new local tt entry: %pM (ttvn: %d)\n", addr,
>  		(uint8_t)atomic_read(&bat_priv->ttvn));
> 
>  	memcpy(tt_local_entry->addr, addr, ETH_ALEN);
>  	tt_local_entry->last_seen = jiffies;
> +	tt_local_entry->flags = 0;

Here you should make use of the NO_FLAGS define you introduced.  :-)


>  	/* the batman interface mac address should never be purged */
>  	if (compare_eth(addr, soft_iface->dev_addr))
> -		tt_local_entry->never_purge = 1;
> -	else
> -		tt_local_entry->never_purge = 0;
> +		tt_local_entry->flags |= TT_LOCAL_NOPURGE;
> +
> +	tt_local_event(bat_priv, NO_FLAGS, addr, false,
> +		       tt_local_entry->flags & TT_CLIENT_WIFI);

Changing "never_purge" to a flag probably is a good idea but should go into a 
separate patch.

Regards,
Marek