[B.A.T.M.A.N.] [RFC v4 15/19] batman-adv: Add network_coding mesh genl configuration

Sven Eckelmann
2019-01-19T15:56:22Z

The mesh interface can use (in an homogeneous mesh) network coding, a
mechanism that aims to increase the overall network throughput by fusing
multiple packets in one transmission.

The BATADV_CMD_SET_MESH/BATADV_CMD_GET_MESH commands allow to set/get the
configuration of this feature using the BATADV_ATTR_NETWORK_CODING_ENABLED
attribute. Setting the u8 to zero will disable this feature and setting it
to something else is enabling this feature.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
---
Cc: Martin Hundeboll <martin@hundeboll.net>
Cc: Marek Lindner <mareklindner@neomailbox.ch>
---
include/uapi/linux/batman_adv.h | 7 +++++++
net/batman-adv/netlink.c | 17 +++++++++++++++++
2 files changed, 24 insertions(+)

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 9f5c85a5..2f0dbcc0 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -463,6 +463,13 @@ enum batadv_nl_attrs {
*/
BATADV_ATTR_MULTICAST_MODE_ENABLED,

+ /**
+ * @BATADV_ATTR_NETWORK_CODING_ENABLED: whether Network Coding (using
+ * some magic to send fewer wifi packets but still the same content) is
+ * enabled or not.
+ */
+ BATADV_ATTR_NETWORK_CODING_ENABLED,
+
/* add attributes above here, update the policy in netlink.c */

/**
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index a0fbad39..9c7f8ca5 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -55,6 +55,7 @@
#include "hard-interface.h"
#include "log.h"
#include "multicast.h"
+#include "network-coding.h"
#include "originator.h"
#include "soft-interface.h"
#include "tp_meter.h"
@@ -156,6 +157,7 @@ static const struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
[BATADV_ATTR_HOP_PENALTY] = { .type = NLA_U8 },
[BATADV_ATTR_LOG_LEVEL] = { .type = NLA_U32 },
[BATADV_ATTR_MULTICAST_MODE_ENABLED] = { .type = NLA_U8 },
+ [BATADV_ATTR_NETWORK_CODING_ENABLED] = { .type = NLA_U8 },
};

/**
@@ -350,6 +352,12 @@ static int batadv_netlink_mesh_put(struct sk_buff *msg,
goto nla_put_failure;
#endif /* CONFIG_BATMAN_ADV_MCAST */

+#ifdef CONFIG_BATMAN_ADV_NC
+ if (nla_put_u8(msg, BATADV_ATTR_NETWORK_CODING_ENABLED,
+ !!atomic_read(&bat_priv->network_coding)))
+ goto nla_put_failure;
+#endif /* CONFIG_BATMAN_ADV_NC */
+
if (primary_if)
batadv_hardif_put(primary_if);

@@ -579,6 +587,15 @@ static int batadv_netlink_set_mesh(struct sk_buff *skb, struct genl_info *info)
}
#endif /* CONFIG_BATMAN_ADV_MCAST */

+#ifdef CONFIG_BATMAN_ADV_NC
+ if (info->attrs[BATADV_ATTR_NETWORK_CODING_ENABLED]) {
+ attr = info->attrs[BATADV_ATTR_NETWORK_CODING_ENABLED];
+
+ atomic_set(&bat_priv->network_coding, !!nla_get_u8(attr));
+ batadv_nc_status_update(bat_priv->soft_iface);
+ }
+#endif /* CONFIG_BATMAN_ADV_NC */
+
batadv_netlink_notify_mesh(bat_priv);

return 0;
--
2.20.1