[ofa-general] [PATCH 3/4 v2] rdma/cm: add ability to specify type of service

[Sean Hefty]

Provide support to specify a type of service for a communication
identifier.  A new function call is used when dealing with IPv4
addresses.  For IPv6 addresses, the ToS is specified through the
traffic class and flow label fields in the sockaddr_in6 structure.

Signed-off-by: Sean Hefty <sean.hefty at intel.com>
---
Minor compile fix-up added.  I incorrectly had the fix included with the
4th patch of this series, rather than with this one, where it belongs.
I removed the mistake from the 4th patch before it was posted.

 drivers/infiniband/core/cma.c |   37 +++++++++++++++++++++++++++++++------
 include/rdma/rdma_cm.h        |   14 ++++++++++++++
 2 files changed, 45 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index 32a0e66..216f5a8 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -138,6 +138,7 @@ struct rdma_id_private {
 	u32			qkey;
 	u32			qp_num;
 	u8			srq;
+	u8			tos;
 };
 
 struct cma_multicast {
@@ -1474,6 +1475,15 @@ err:
 }
 EXPORT_SYMBOL(rdma_listen);
 
+void rdma_set_service_type(struct rdma_cm_id *id, int tos)
+{
+	struct rdma_id_private *id_priv;
+
+	id_priv = container_of(id, struct rdma_id_private, id);
+	id_priv->tos = (u8) tos;
+}
+EXPORT_SYMBOL(rdma_set_service_type);
+
 static void cma_query_handler(int status, struct ib_sa_path_rec *path_rec,
 			      void *context)
 {
@@ -1500,6 +1510,8 @@ static int cma_query_ib_route(struct rdma_id_private *id_priv, int
timeout_ms,
 {
 	struct rdma_dev_addr *addr = &id_priv->id.route.addr.dev_addr;
 	struct ib_sa_path_rec path_rec;
+	ib_sa_comp_mask comp_mask;
+	struct sockaddr_in6 *sin6;
 
 	memset(&path_rec, 0, sizeof path_rec);
 	ib_addr_get_sgid(addr, &path_rec.sgid);
@@ -1508,13 +1520,26 @@ static int cma_query_ib_route(struct rdma_id_private *id_priv, int
timeout_ms,
 	path_rec.numb_path = 1;
 	path_rec.reversible = 1;
 
+	comp_mask = IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
+		    IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH |
+		    IB_SA_PATH_REC_REVERSIBLE;
+
+	if (id_priv->id.route.addr.src_addr.sa_family == AF_INET) {
+		path_rec.qos_class = cpu_to_be16((u16) id_priv->tos);
+		comp_mask |= IB_SA_PATH_REC_QOS_CLASS;
+	} else {
+		sin6 = (struct sockaddr_in6 *) &id_priv->id.route.addr.src_addr;
+		path_rec.flow_label = sin6->sin6_flowinfo;
+		path_rec.traffic_class = (u8) (be32_to_cpu(sin6->sin6_flowinfo) >> 20);
+		comp_mask |= IB_SA_PATH_REC_FLOW_LABEL |
+			     IB_SA_PATH_REC_TRAFFIC_CLASS;
+	}
+
 	id_priv->query_id = ib_sa_path_rec_get(&sa_client, id_priv->id.device,
-				id_priv->id.port_num, &path_rec,
-				IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID |
-				IB_SA_PATH_REC_PKEY | IB_SA_PATH_REC_NUMB_PATH |
-				IB_SA_PATH_REC_REVERSIBLE,
-				timeout_ms, GFP_KERNEL,
-				cma_query_handler, work, &id_priv->query);
+					       id_priv->id.port_num, &path_rec,
+					       comp_mask, timeout_ms,
+					       GFP_KERNEL, cma_query_handler,
+					       work, &id_priv->query);
 
 	return (id_priv->query_id < 0) ? id_priv->query_id : 0;
 }
diff --git a/include/rdma/rdma_cm.h b/include/rdma/rdma_cm.h
index 2d6a770..010f876 100644
--- a/include/rdma/rdma_cm.h
+++ b/include/rdma/rdma_cm.h
@@ -314,4 +314,18 @@ int rdma_join_multicast(struct rdma_cm_id *id, struct sockaddr *addr,
  */
 void rdma_leave_multicast(struct rdma_cm_id *id, struct sockaddr *addr);
 
+/**
+ * rdma_set_service_type - Set the type of service associated with a
+ *   connection identifier.
+ * @id: Communication identifier to associated with service type.
+ * @tos: Type of service.
+ *
+ * The type of service is interpretted as a differentiated service
+ * field (RFC 2474).  The service type should be specified before
+ * performing route resolution, as existing communication on the
+ * connection identifier may be unaffected.  The type of service
+ * requested may not be supported by the network to all destinations.
+ */
+void rdma_set_service_type(struct rdma_cm_id *id, int tos);
+
 #endif /* RDMA_CM_H */