RDS: add t_mp_capable bit to be set by MP capable transports

The t_mp_capable bit will be used in the core rds module
to support multipathing logic when the transport supports it.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/net/rds/rds.h b/net/rds/rds.h
index ca31a07f70f5..28f001cbc893 100644
--- a/net/rds/rds.h
+++ b/net/rds/rds.h
@@ -446,7 +446,8 @@ struct rds_transport {
         char                    t_name[TRANSNAMSIZ];
         struct list_head        t_item;
         struct module           *t_owner;
-        unsigned int            t_prefer_loopback:1;
+        unsigned int            t_prefer_loopback:1,
+                                t_mp_capable:1;
         unsigned int            t_type;
 
         int (*laddr_check)(struct net *net, __be32 addr);
@@ -673,6 +674,7 @@ rds_conn_path_transition(struct rds_conn_path *cp, int old, int new)
 static inline int
 rds_conn_transition(struct rds_connection *conn, int old, int new)
 {
+        WARN_ON(conn->c_trans->t_mp_capable);
         return rds_conn_path_transition(&conn->c_path[0], old, new);
 }
 
@@ -685,6 +687,7 @@ rds_conn_path_state(struct rds_conn_path *cp)
 static inline int
 rds_conn_state(struct rds_connection *conn)
 {
+        WARN_ON(conn->c_trans->t_mp_capable);
         return rds_conn_path_state(&conn->c_path[0]);
 }
 
@@ -697,6 +700,7 @@ rds_conn_path_up(struct rds_conn_path *cp)
 static inline int
 rds_conn_up(struct rds_connection *conn)
 {
+        WARN_ON(conn->c_trans->t_mp_capable);
         return rds_conn_path_up(&conn->c_path[0]);
 }
 
@@ -709,6 +713,7 @@ rds_conn_path_connecting(struct rds_conn_path *cp)
 static inline int
 rds_conn_connecting(struct rds_connection *conn)
 {
+        WARN_ON(conn->c_trans->t_mp_capable);
         return rds_conn_path_connecting(&conn->c_path[0]);
 }