[B.A.T.M.A.N.] [RFC v4 12/19] batman-adv: Add hop_penalty mesh genl configuration

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

The TQ (B.A.T.M.A.N. IV) and throughput values (B.A.T.M.A.N. V) are reduced
when they are forwarded. One of the reductions is the penalty for
traversing an additional hop. This hop_penalty (0-255) defines the
percentage of reduction (0-100%).

The BATADV_CMD_SET_MESH/BATADV_CMD_GET_MESH commands allow to set/get the
configuration of this feature using the u8 BATADV_ATTR_HOP_PENALTY
attribute.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
---
Cc: Linus Lüssing <linus.luessing@c0d3.blue>
Cc: Marek Lindner <mareklindner@neomailbox.ch>
Cc: Antonio Quartulli <a@unstable.cc>
Cc: Simon Wunderlich <sw@simonwunderlich.de>
---
include/uapi/linux/batman_adv.h | 6 ++++++
net/batman-adv/netlink.c | 11 +++++++++++
2 files changed, 17 insertions(+)

diff --git a/include/uapi/linux/batman_adv.h b/include/uapi/linux/batman_adv.h
index 165272be..b37cb923 100644
--- a/include/uapi/linux/batman_adv.h
+++ b/include/uapi/linux/batman_adv.h
@@ -443,6 +443,12 @@ enum batadv_nl_attrs {
*/
BATADV_ATTR_GW_SEL_CLASS,

+ /**
+ * @BATADV_ATTR_HOP_PENALTY: defines the penalty which will be applied
+ * to an originator message's tq-field on every hop.
+ */
+ BATADV_ATTR_HOP_PENALTY,
+
/* 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 8db3a2a4..8602129f 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -152,6 +152,7 @@ static const struct nla_policy batadv_netlink_policy[NUM_BATADV_ATTR] = {
[BATADV_ATTR_GW_BANDWIDTH_UP] = { .type = NLA_U32 },
[BATADV_ATTR_GW_MODE] = { .type = NLA_U8 },
[BATADV_ATTR_GW_SEL_CLASS] = { .type = NLA_U32 },
+ [BATADV_ATTR_HOP_PENALTY] = { .type = NLA_U8 },
};

/**
@@ -330,6 +331,10 @@ static int batadv_netlink_mesh_put(struct sk_buff *msg,
goto nla_put_failure;
}

+ if (nla_put_u8(msg, BATADV_ATTR_HOP_PENALTY,
+ atomic_read(&bat_priv->hop_penalty)))
+ goto nla_put_failure;
+
if (primary_if)
batadv_hardif_put(primary_if);

@@ -536,6 +541,12 @@ static int batadv_netlink_set_mesh(struct sk_buff *skb, struct genl_info *info)
}
}

+ if (info->attrs[BATADV_ATTR_HOP_PENALTY]) {
+ attr = info->attrs[BATADV_ATTR_HOP_PENALTY];
+
+ atomic_set(&bat_priv->hop_penalty, nla_get_u8(attr));
+ }
+
batadv_netlink_notify_mesh(bat_priv);

return 0;
--
2.20.1