IB/cma: Resolve route only while receiving CM requests

Currently CM request for RoCE follows following flow.
rdma_create_id()
rdma_resolve_addr()
rdma_resolve_route()
For RC QPs:
rdma_connect()
->cma_connect_ib()
  ->ib_send_cm_req()
    ->cm_init_av_by_path()
      ->ib_init_ah_attr_from_path()
For UD QPs:
rdma_connect()
->cma_resolve_ib_udp()
  ->ib_send_cm_sidr_req()
    ->cm_init_av_by_path()
      ->ib_init_ah_attr_from_path()

In both the flows, route is already resolved before sending CM requests.
Therefore, code is refactored to avoid resolving route second time in
ib_cm layer.
ib_init_ah_attr_from_path() is extended to resolve route when it is not
yet resolved for RoCE link layer. This is achieved by caller setting
route_resolved field in path record whenever it has route already
resolved.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c
index 1cfec68c7911..a61ec7e33613 100644
--- a/drivers/infiniband/core/sa_query.c
+++ b/drivers/infiniband/core/sa_query.c
@@ -1248,6 +1248,9 @@ roce_resolve_route_from_path(struct ib_device *device, u8 port_num,
 	} sgid_addr, dgid_addr;
 	int ret;
 
+	if (rec->roce.route_resolved)
+		return 0;
+
 	if (!device->get_netdev)
 		return -EOPNOTSUPP;
 
@@ -1287,6 +1290,8 @@ roce_resolve_route_from_path(struct ib_device *device, u8 port_num,
 		dev_put(ndev);
 done:
 	dev_put(idev);
+	if (!ret)
+		rec->roce.route_resolved = true;
 	return ret;
 }