IB/rdmavt: Macroize override checks during driver registration

Add a macro to cut down on writing the same lines over and over again for
what will be a large number of functions that will be supported.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

drivers/infiniband/sw/rdmavt/vt.c

@@ -64,29 +64,25 @@ static void rvt_cleanup(void)
 }
 module_exit(rvt_cleanup);
 
+/*
+ * Check driver override. If driver passes a value use it, otherwise we use our
+ * own value.
+ */
+#define CHECK_DRIVER_OVERRIDE(rdi, x) \
+	rdi->ibdev.x = rdi->ibdev.x ? : rvt_ ##x
+
 int rvt_register_device(struct rvt_dev_info *rdi)
 {
 	if (!rdi)
 		return -EINVAL;
 
-	/*
-	 * Drivers have the option to override anything in the ibdev that they
-	 * want to specifically handle. VT needs to check for things it supports
-	 * and if the driver wants to handle that functionality let it. We may
-	 * come up with a better mechanism that simplifies the code at some
-	 * point.
-	 */
-
 	/* DMA Operations */
 	rdi->ibdev.dma_ops =
 		rdi->ibdev.dma_ops ? : &rvt_default_dma_mapping_ops;
 
 	/* Protection Domain */
-	rdi->ibdev.alloc_pd =
-		rdi->ibdev.alloc_pd ? : rvt_alloc_pd;
-	rdi->ibdev.dealloc_pd =
-		rdi->ibdev.dealloc_pd ? : rvt_dealloc_pd;
-
+	CHECK_DRIVER_OVERRIDE(rdi, alloc_pd);
+	CHECK_DRIVER_OVERRIDE(rdi, dealloc_pd);
 	spin_lock_init(&rdi->n_pds_lock);
 	rdi->n_pds_allocated = 0;