[B.A.T.M.A.N.] [PATCH 07/15] batman-adv: Distributed ARP Table - increase default soft_iface ARP table timeout

Antonio Quartulli
2012-04-25T13:27:03Z

The default timeout value for ARP entries belonging to any soft_iface
ARP table has been incremented by a factor 4. This is necessary because the DHT
will store several network entries in the soft_iface ARP table.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
---
net/batman-adv/distributed-arp-table.c | 20 ++++++++++++++++++++
net/batman-adv/distributed-arp-table.h | 1 +
net/batman-adv/main.h | 4 ++++
net/batman-adv/soft-interface.c | 2 ++
4 files changed, 27 insertions(+)

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index f3b63ef..24b17131 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -23,6 +23,7 @@
#include <linux/if_arp.h>
/* needed to use arp_tbl */
#include <net/arp.h>
+#include <linux/inetdevice.h>

#include "main.h"
#include "distributed-arp-table.h"
@@ -583,3 +584,22 @@ bool dat_drop_broadcast_packet(struct bat_priv *bat_priv,
}
return false;
}
+
+void arp_change_timeout(struct net_device *soft_iface, const char *name)
+{
+ struct in_device *in_dev = in_dev_get(soft_iface);
+ if (!in_dev) {
+ pr_err("Unable to set ARP parameters for the batman interface '%s'\n",
+ name);
+ return;
+ }
+
+ /* Introduce a delay in the ARP state-machine transactions. Entries
+ * will be kept in the ARP table for the default time multiplied by 4
+ */
+ in_dev->arp_parms->base_reachable_time *= ARP_TIMEOUT_FACTOR;
+ in_dev->arp_parms->gc_staletime *= ARP_TIMEOUT_FACTOR;
+ in_dev->arp_parms->reachable_time *= ARP_TIMEOUT_FACTOR;
+
+ in_dev_put(in_dev);
+}
diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h
index 8b7aa87..3a4f710 100644
--- a/net/batman-adv/distributed-arp-table.h
+++ b/net/batman-adv/distributed-arp-table.h
@@ -47,6 +47,7 @@ bool dat_snoop_incoming_arp_reply(struct bat_priv *bat_priv,
struct sk_buff *skb, int hdr_size);
bool dat_drop_broadcast_packet(struct bat_priv *bat_priv,
struct forw_packet *forw_packet);
+void arp_change_timeout(struct net_device *soft_iface, const char *name);

/* hash function to choose an entry in a hash table of given size.
* hash algorithm from http://en.wikipedia.org/wiki/Hash_table
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index 57023c3..c11c8df 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -71,6 +71,10 @@
#define ARP_REQ_DELAY 250
/* numbers of originator to contact for any PUT/GET DHT operation */
#define DHT_CANDIDATES_NUM 3
+/* Factor which default ARP timeout values of the soft_iface table are
+ * multiplied by
+ */
+#define ARP_TIMEOUT_FACTOR 4

#define LOG_BUF_LEN 8192 /* has to be a power of 2 */

diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 3a1483a..b56dafd 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -381,6 +381,8 @@ struct net_device *softif_create(const char *name)
goto free_soft_iface;
}

+ arp_change_timeout(soft_iface, name);
+
bat_priv = netdev_priv(soft_iface);

atomic_set(&bat_priv->aggregated_ogms, 1);
--
1.7.9.4