RDMA/cxgb4: Call iwpm_init() only once

We need to only register with the iwpm core once.  Currently it is
being done for every adapter, which causes a failure for each adapter
but the first, making multiple adapters unusable.

Fixes: 9eccfe109b27 ("RDMA/cxgb4: Add support for iWARP Port Mapper user space service")
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>
diff --git a/drivers/infiniband/hw/cxgb4/device.c b/drivers/infiniband/hw/cxgb4/device.c
index 16b75de..7db82b2 100644
--- a/drivers/infiniband/hw/cxgb4/device.c
+++ b/drivers/infiniband/hw/cxgb4/device.c
@@ -730,7 +730,6 @@
 	if (ctx->dev->rdev.oc_mw_kva)
 		iounmap(ctx->dev->rdev.oc_mw_kva);
 	ib_dealloc_device(&ctx->dev->ibdev);
-	iwpm_exit(RDMA_NL_C4IW);
 	ctx->dev = NULL;
 }
 
@@ -827,12 +826,6 @@
 		setup_debugfs(devp);
 	}
 
-	ret = iwpm_init(RDMA_NL_C4IW);
-	if (ret) {
-		pr_err("port mapper initialization failed with %d\n", ret);
-		ib_dealloc_device(&devp->ibdev);
-		return ERR_PTR(ret);
-	}
 
 	return devp;
 }
@@ -1333,6 +1326,15 @@
 		pr_err("%s[%u]: Failed to add netlink callback\n"
 		       , __func__, __LINE__);
 
+	err = iwpm_init(RDMA_NL_C4IW);
+	if (err) {
+		pr_err("port mapper initialization failed with %d\n", err);
+		ibnl_remove_client(RDMA_NL_C4IW);
+		c4iw_cm_term();
+		debugfs_remove_recursive(c4iw_debugfs_root);
+		return err;
+	}
+
 	cxgb4_register_uld(CXGB4_ULD_RDMA, &c4iw_uld_info);
 
 	return 0;
@@ -1350,6 +1352,7 @@
 	}
 	mutex_unlock(&dev_mutex);
 	cxgb4_unregister_uld(CXGB4_ULD_RDMA);
+	iwpm_exit(RDMA_NL_C4IW);
 	ibnl_remove_client(RDMA_NL_C4IW);
 	c4iw_cm_term();
 	debugfs_remove_recursive(c4iw_debugfs_root);