[openib-general] [PATCH 2/3] RDMA CM: allowing userspace querying for IP information before a device is known

[Sean Hefty]

Currently, the userspace library cannot query for address/routing information
unless the underlying cm_id has been bound to a device.  This functionality
is needed in order to obtain address/port information after binding, but before
a local device has been assigned.

Signed-off-by: Sean Hefty <sean.hefty at intel.com>

---

Index: ucma.c
===================================================================
--- ucma.c	(revision 6063)
+++ ucma.c	(working copy)
@@ -465,11 +465,7 @@ static ssize_t ucma_query_route(struct u
 	if (IS_ERR(ctx))
 		return PTR_ERR(ctx);
 
-	if (!ctx->cm_id->device) {
-		ret = -ENODEV;
-		goto out;
-	}
-
+	memset(&resp, 0, sizeof resp);
 	addr = &ctx->cm_id->route.addr.src_addr;
 	memcpy(&resp.src_addr, addr, addr->sa_family == AF_INET ?
 				     sizeof(struct sockaddr_in) : 
@@ -478,6 +474,9 @@ static ssize_t ucma_query_route(struct u
 	memcpy(&resp.dst_addr, addr, addr->sa_family == AF_INET ?
 				     sizeof(struct sockaddr_in) : 
 				     sizeof(struct sockaddr_in6));
+	if (!ctx->cm_id->device)
+		goto out;
+
 	resp.node_guid = ctx->cm_id->device->node_guid;
 	resp.port_num = ctx->cm_id->port_num;
 	switch (rdma_node_get_transport(ctx->cm_id->device->node_type)) {
@@ -487,11 +486,11 @@ static ssize_t ucma_query_route(struct u
 		break;
 	}
 
+out:
 	if (copy_to_user((void __user *)(unsigned long)cmd.response,
 			 &resp, sizeof(resp)))
 		ret = -EFAULT;
 
-out:
 	ucma_put_ctx(ctx);
 	return ret;
 }