batman-adv: Add lower layer needed_(head|tail)room to own ones

The maximum of hard_header_len and maximum of all needed_(head|tail)room of
all slave interfaces of a batman-adv device must be used to define the
batman-adv device needed_(head|tail)room. This is required to avoid too
small buffer problems when these slave devices try to send the encapsulated
packet in a tx path without the possibility to resize the skbuff.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
This commit is contained in:
Sven Eckelmann 2015-08-07 19:28:42 +02:00 committed by Antonio Quartulli
parent a5256f7e74
commit 7bca68c784
2 changed files with 41 additions and 2 deletions

View file

@ -252,6 +252,44 @@ static void batadv_check_known_mac_addr(const struct net_device *net_dev)
rcu_read_unlock();
}
/**
* batadv_hardif_recalc_extra_skbroom() - Recalculate skbuff extra head/tailroom
* @soft_iface: netdev struct of the mesh interface
*/
static void batadv_hardif_recalc_extra_skbroom(struct net_device *soft_iface)
{
const struct batadv_hard_iface *hard_iface;
unsigned short lower_header_len = ETH_HLEN;
unsigned short lower_headroom = 0;
unsigned short lower_tailroom = 0;
unsigned short needed_headroom;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->if_status == BATADV_IF_NOT_IN_USE)
continue;
if (hard_iface->soft_iface != soft_iface)
continue;
lower_header_len = max_t(unsigned short, lower_header_len,
hard_iface->net_dev->hard_header_len);
lower_headroom = max_t(unsigned short, lower_headroom,
hard_iface->net_dev->needed_headroom);
lower_tailroom = max_t(unsigned short, lower_tailroom,
hard_iface->net_dev->needed_tailroom);
}
rcu_read_unlock();
needed_headroom = lower_headroom + (lower_header_len - ETH_HLEN);
needed_headroom += batadv_max_header_len();
soft_iface->needed_headroom = needed_headroom;
soft_iface->needed_tailroom = lower_tailroom;
}
int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
@ -474,6 +512,8 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
"Not using interface %s (retrying later): interface not active\n",
hard_iface->net_dev->name);
batadv_hardif_recalc_extra_skbroom(soft_iface);
/* begin scheduling originator messages on that interface */
batadv_schedule_bat_ogm(hard_iface);
@ -529,6 +569,7 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
dev_put(hard_iface->soft_iface);
netdev_upper_dev_unlink(hard_iface->net_dev, hard_iface->soft_iface);
batadv_hardif_recalc_extra_skbroom(hard_iface->soft_iface);
/* nobody uses this interface anymore */
if (!bat_priv->num_ifaces) {

View file

@ -947,8 +947,6 @@ static void batadv_softif_init_early(struct net_device *dev)
* have not been initialized yet
*/
dev->mtu = ETH_DATA_LEN;
/* reserve more space in the skbuff for our header */
dev->hard_header_len = batadv_max_header_len();
/* generate random address */
eth_hw_addr_random(dev);