tipc: implement configuration of UDP media MTU
In previous commit, we changed the default emulated MTU for UDP bearers
to 14k.
This commit adds the functionality to set/change the default value
by configuring new MTU for UDP media. UDP bearer(s) have to be disabled
and enabled back for the new MTU to take effect.
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/uapi/linux/tipc_netlink.h b/include/uapi/linux/tipc_netlink.h
index 0affb68..85c1198 100644
--- a/include/uapi/linux/tipc_netlink.h
+++ b/include/uapi/linux/tipc_netlink.h
@@ -266,6 +266,7 @@ enum {
TIPC_NLA_PROP_PRIO, /* u32 */
TIPC_NLA_PROP_TOL, /* u32 */
TIPC_NLA_PROP_WIN, /* u32 */
+ TIPC_NLA_PROP_MTU, /* u32 */
__TIPC_NLA_PROP_MAX,
TIPC_NLA_PROP_MAX = __TIPC_NLA_PROP_MAX - 1
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index f7d47c8..a22caf9 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -1029,6 +1029,9 @@ static int __tipc_nl_add_media(struct tipc_nl_msg *msg,
goto prop_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, media->window))
goto prop_msg_full;
+ if (media->type_id == TIPC_MEDIA_TYPE_UDP)
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_MTU, media->mtu))
+ goto prop_msg_full;
nla_nest_end(msg->skb, prop);
nla_nest_end(msg->skb, attrs);
@@ -1158,6 +1161,16 @@ int __tipc_nl_media_set(struct sk_buff *skb, struct genl_info *info)
m->priority = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
if (props[TIPC_NLA_PROP_WIN])
m->window = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+ if (props[TIPC_NLA_PROP_MTU]) {
+ if (m->type_id != TIPC_MEDIA_TYPE_UDP)
+ return -EINVAL;
+#ifdef CONFIG_TIPC_MEDIA_UDP
+ if (tipc_udp_mtu_bad(nla_get_u32
+ (props[TIPC_NLA_PROP_MTU])))
+ return -EINVAL;
+ m->mtu = nla_get_u32(props[TIPC_NLA_PROP_MTU]);
+#endif
+ }
}
return 0;
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 6efcee6..394290cbb 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -94,6 +94,8 @@ struct tipc_bearer;
* @priority: default link (and bearer) priority
* @tolerance: default time (in ms) before declaring link failure
* @window: default window (in packets) before declaring link congestion
+ * @mtu: max packet size bearer can support for media type not dependent on
+ * underlying device MTU
* @type_id: TIPC media identifier
* @hwaddr_len: TIPC media address len
* @name: media name
@@ -118,6 +120,7 @@ struct tipc_media {
u32 priority;
u32 tolerance;
u32 window;
+ u32 mtu;
u32 type_id;
u32 hwaddr_len;
char name[TIPC_MAX_MEDIA_NAME];
diff --git a/net/tipc/udp_media.h b/net/tipc/udp_media.h
index 281bbae..e7455cc 100644
--- a/net/tipc/udp_media.h
+++ b/net/tipc/udp_media.h
@@ -38,9 +38,23 @@
#ifndef _TIPC_UDP_MEDIA_H
#define _TIPC_UDP_MEDIA_H
+#include <linux/ip.h>
+#include <linux/udp.h>
+
int tipc_udp_nl_bearer_add(struct tipc_bearer *b, struct nlattr *attr);
int tipc_udp_nl_add_bearer_data(struct tipc_nl_msg *msg, struct tipc_bearer *b);
int tipc_udp_nl_dump_remoteip(struct sk_buff *skb, struct netlink_callback *cb);
+/* check if configured MTU is too low for tipc headers */
+static inline bool tipc_udp_mtu_bad(u32 mtu)
+{
+ if (mtu >= (TIPC_MIN_BEARER_MTU + sizeof(struct iphdr) +
+ sizeof(struct udphdr)))
+ return false;
+
+ pr_warn("MTU too low for tipc bearer\n");
+ return true;
+}
+
#endif
#endif
