[ewg] [PATCH RFCv2] RDMA/CMA: Allocate PS_TCP ports from the host TCP port space.

[Steve Wise]

From: Steve Wise <swise at opengridcomputing.com>

This is needed for iwarp providers that support native and rdma
connections over the same interface.

Optionally turned on by the new rdma_cm unify_tcp_port_space module
option.

Signed-off-by: Steve Wise <swise at opengridcomputing.com>
---

 drivers/infiniband/core/cma.c |   34 +++++++++++++++++++++++++++++++++-
 1 files changed, 33 insertions(+), 1 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index e980ff3..bffc8df 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -54,6 +54,11 @@ MODULE_AUTHOR("Sean Hefty");
 MODULE_DESCRIPTION("Generic RDMA CM Agent");
 MODULE_LICENSE("Dual BSD/GPL");
 
+int unify_tcp_port_space = 0;
+module_param(unify_tcp_port_space, int, 0644);
+MODULE_PARM_DESC(unify_tcp_port_space, "Unify the host TCP and RDMA port "
+		 "space allocation (default=0)");
+
 #define CMA_CM_RESPONSE_TIMEOUT 20
 #define CMA_MAX_CM_RETRIES 15
 #define CMA_CM_MRA_SETTING (IB_CM_MRA_FLAG_DELAY | 24)
@@ -117,6 +122,7 @@ struct rdma_id_private {
 	struct rdma_cm_id	id;
 
 	struct rdma_bind_list	*bind_list;
+	struct socket		*sock;
 	struct hlist_node	node;
 	struct list_head	list; /* listen_any_list or cma_device.list */
 	struct list_head	listen_list; /* per device listens */
@@ -809,6 +815,8 @@ static void cma_release_port(struct rdma_id_private *id_priv)
 		kfree(bind_list);
 	}
 	mutex_unlock(&lock);
+	if (id_priv->sock)
+		sock_release(id_priv->sock);
 }
 
 static void cma_leave_mc_groups(struct rdma_id_private *id_priv)
@@ -2037,6 +2045,25 @@ static int cma_use_port(struct idr *ps, struct rdma_id_private *id_priv)
 	return 0;
 }
 
+static int cma_get_tcp_port(struct rdma_id_private *id_priv)
+{
+	int ret;
+	struct socket *sock;
+
+	ret = sock_create_kern(AF_INET, SOCK_STREAM, IPPROTO_TCP, &sock);
+	if (ret)
+		return ret;
+	ret = sock->ops->bind(sock,
+			(struct sockaddr *)&id_priv->id.route.addr.src_addr,
+			ip_addr_size(&id_priv->id.route.addr.src_addr));
+	if (ret) {
+		sock_release(sock);
+		return ret;
+	}
+	id_priv->sock = sock;
+	return 0;	
+}
+
 static int cma_get_port(struct rdma_id_private *id_priv)
 {
 	struct idr *ps;
@@ -2048,6 +2075,11 @@ static int cma_get_port(struct rdma_id_private *id_priv)
 		break;
 	case RDMA_PS_TCP:
 		ps = &tcp_ps;
+		if (unify_tcp_port_space) {
+			ret = cma_get_tcp_port(id_priv);
+			if (ret)
+				goto out;
+		}
 		break;
 	case RDMA_PS_UDP:
 		ps = &udp_ps;
@@ -2065,7 +2097,7 @@ static int cma_get_port(struct rdma_id_private *id_priv)
 	else
 		ret = cma_use_port(ps, id_priv);
 	mutex_unlock(&lock);
-
+out:
 	return ret;
 }