IB/core: Add support for modify CQ

Add support for modifying CQ parameters for controlling event
generation moderation.

Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index 8ffb5f2..0504208 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -630,6 +630,13 @@
 }
 EXPORT_SYMBOL(ib_create_cq);
 
+int ib_modify_cq(struct ib_cq *cq, u16 cq_count, u16 cq_period)
+{
+	return cq->device->modify_cq ?
+		cq->device->modify_cq(cq, cq_count, cq_period) : -ENOSYS;
+}
+EXPORT_SYMBOL(ib_modify_cq);
+
 int ib_destroy_cq(struct ib_cq *cq)
 {
 	if (atomic_read(&cq->usecnt))