RDMA/rxe: Send last wqe reached event on qp cleanup

The IBA requires:
	o11-5.2.5: If the HCA supports SRQ, for RC and UD service,
	the CI shall generate a Last WQE Reached Affiliated Asynchronous
	Event on a QP that is in the Error State and is associated with
	an SRQ when either:
		• a CQE is generated for the last WQE, or
		• the QP gets in the Error State and there are no more
		  WQEs on the RQ.

This patch implements this behavior in flush_recv_queue() which is called
as a result of rxe_qp_error() being called whenever the qp is put into the
error state. The rxe responder executes SRQ WQEs directly from the SRQ so
there are never more WQES on the RQ.

Link: https://lore.kernel.org/r/20230602164229.9277-1-rpearsonhpe@gmail.comSigned-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/sw/rxe/rxe_resp.c

@@ -1455,8 +1455,17 @@ static void flush_recv_queue(struct rxe_qp *qp, bool notify)
 	struct rxe_recv_wqe *wqe;
 	int err;
 
-	if (qp->srq)
+	if (qp->srq) {
+		if (notify && qp->ibqp.event_handler) {
+			struct ib_event ev;
+
+			ev.device = qp->ibqp.device;
+			ev.element.qp = &qp->ibqp;
+			ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
+			qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
+		}
 		return;
+	}
 
 	while ((wqe = queue_head(q, q->type))) {
 		if (notify) {