[ofw] [PATCH 5/11] librdmacm: allow user to specify max rdma resources

[Hefty, Sean]

Automatically negotiate the maximum usable RDMA resources if requested
by the user.

From: Sean Hefty <sean.hefty at intel.com>
---
 trunk/ulp/librdmacm/include/rdma/rdma_cma.h |    5 +++
 trunk/ulp/librdmacm/src/cma.cpp             |   43 ++++++++++++++++++++++-----
 2 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/trunk/ulp/librdmacm/include/rdma/rdma_cma.h b/trunk/ulp/librdmacm/include/rdma/rdma_cma.h
index 16f7f21..294a75b 100644
--- a/trunk/ulp/librdmacm/include/rdma/rdma_cma.h
+++ b/trunk/ulp/librdmacm/include/rdma/rdma_cma.h
@@ -146,6 +146,11 @@ struct rdma_cm_id
 	struct ibv_cq				*recv_cq;
 };
 
+enum {
+	RDMA_MAX_RESP_RES = 0xFF,
+	RDMA_MAX_INIT_DEPTH = 0xFF
+};
+
 struct rdma_conn_param
 {
 	const void *private_data;
diff --git a/trunk/ulp/librdmacm/src/cma.cpp b/trunk/ulp/librdmacm/src/cma.cpp
index 0d6e6f5..05c672d 100644
--- a/trunk/ulp/librdmacm/src/cma.cpp
+++ b/trunk/ulp/librdmacm/src/cma.cpp
@@ -74,6 +74,8 @@ struct cma_id_private
 	int							index;
 	volatile LONG				refcnt;
 	struct rdma_cm_id			**req_list;
+	uint8_t						initiator_depth;
+	uint8_t						responder_resources;
 };
 
 struct cma_device
@@ -737,15 +739,20 @@ void rdma_destroy_qp(struct rdma_cm_id *id)
 }
 
 static int ucma_valid_param(struct cma_id_private *id_priv,
-							struct rdma_conn_param *conn_param)
+							struct rdma_conn_param *param)
 {
 	if (id_priv->id.ps != RDMA_PS_TCP) {
 		return 0;
 	}
 
-	if ((conn_param->responder_resources > id_priv->cma_dev->max_responder_resources) ||
-		(conn_param->initiator_depth > id_priv->cma_dev->max_initiator_depth)) {
-		return -1;
+	if ((param->responder_resources != RDMA_MAX_RESP_RES) &&
+		(param->responder_resources > id_priv->cma_dev->max_responder_resources)) {
+		return rdma_seterrno(EINVAL);
+	}
+		
+	if ((param->initiator_depth != RDMA_MAX_INIT_DEPTH) &&
+		(param->initiator_depth > id_priv->cma_dev->max_initiator_depth)) {
+		return rdma_seterrno(EINVAL);
 	}
 
 	return 0;
@@ -765,9 +772,14 @@ int rdma_connect(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
 		return ret;
 	}
 
+	id_priv->responder_resources = min(conn_param->responder_resources,
+									   id_priv->cma_dev->max_responder_resources);
+	id_priv->initiator_depth = min(conn_param->initiator_depth,
+								   id_priv->cma_dev->max_initiator_depth);
+
 	RtlZeroMemory(&attr, sizeof attr);
-	attr.ResponderResources = conn_param->responder_resources;
-	attr.InitiatorDepth = conn_param->initiator_depth;
+	attr.ResponderResources = id_priv->responder_resources;
+	attr.InitiatorDepth = id_priv->initiator_depth;
 	attr.RetryCount = conn_param->retry_count;
 	attr.RnrRetryCount = conn_param->rnr_retry_count;
 	if ((attr.DataLength = conn_param->private_data_len)) {
@@ -892,9 +904,22 @@ int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
 		return ret;
 	}
 
+	if (conn_param->initiator_depth == RDMA_MAX_INIT_DEPTH) {
+		id_priv->initiator_depth = min(id_priv->initiator_depth,
+									   id_priv->cma_dev->max_initiator_depth);
+	} else {
+		id_priv->initiator_depth = conn_param->initiator_depth;
+	}
+	if (conn_param->responder_resources == RDMA_MAX_RESP_RES) {
+		id_priv->responder_resources = min(id_priv->responder_resources,
+										   id_priv->cma_dev->max_responder_resources);
+	} else {
+		id_priv->responder_resources = conn_param->responder_resources;
+	}
+
 	RtlZeroMemory(&attr, sizeof attr);
-	attr.ResponderResources = conn_param->responder_resources;
-	attr.InitiatorDepth = conn_param->initiator_depth;
+	attr.ResponderResources = id_priv->responder_resources;
+	attr.InitiatorDepth = id_priv->initiator_depth;
 	attr.RetryCount = conn_param->retry_count;
 	attr.RnrRetryCount = conn_param->rnr_retry_count;
 	if ((attr.DataLength = conn_param->private_data_len)) {
@@ -1004,6 +1029,8 @@ static int ucma_process_conn_req(struct cma_event *event)
 	event->event.event = RDMA_CM_EVENT_CONNECT_REQUEST;
 	id_priv->state = cma_passive_connect;
 	event->event.listen_id = &listen->id;
+	id_priv->initiator_depth = event->event.param.conn.initiator_depth;
+	id_priv->responder_resources = event->event.param.conn.responder_resources;
 
 	return 0;