RDMA/nes: Rework the disconn routine for terminate and flushing

The disconn routine has been reworked to acoomodate the terminate and
flushing changes.  The routine has been reorganized to make all the
decisions at the start then it performs all the required operations.
This simplified the lock handling and is easier to follow.
Signed-off-by: Don Wood <donald.e.wood@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/nes/nes_cm.c

@@ -2493,7 +2493,12 @@ static int nes_cm_disconn_true(struct nes_qp *nesqp)
 	u16 last_ae;
 	u8 original_hw_tcp_state;
 	u8 original_ibqp_state;
-	u8 issued_disconnect_reset = 0;
+	enum iw_cm_event_type disconn_status = IW_CM_EVENT_STATUS_OK;
+	int issue_disconn = 0;
+	int issue_close = 0;
+	int issue_flush = 0;
+	u32 flush_q = NES_CQP_FLUSH_RQ;
+	struct ib_event ibevent;
 
 	if (!nesqp) {
 		nes_debug(NES_DBG_CM, "disconnect_worker nesqp is NULL\n");
@@ -2517,24 +2522,55 @@ static int nes_cm_disconn_true(struct nes_qp *nesqp)
 	original_ibqp_state   = nesqp->ibqp_state;
 	last_ae = nesqp->last_aeq;
 
+	if (nesqp->term_flags) {
+		issue_disconn = 1;
+		issue_close = 1;
+		nesqp->cm_id = NULL;
+		if (nesqp->flush_issued == 0) {
+			nesqp->flush_issued = 1;
+			issue_flush = 1;
+		}
+	} else if ((original_hw_tcp_state == NES_AEQE_TCP_STATE_CLOSE_WAIT) ||
+			((original_ibqp_state == IB_QPS_RTS) &&
+			(last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET))) {
+		issue_disconn = 1;
+		if (last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET)
+			disconn_status = IW_CM_EVENT_STATUS_RESET;
+	}
+
+	if (((original_hw_tcp_state == NES_AEQE_TCP_STATE_CLOSED) ||
+		 (original_hw_tcp_state == NES_AEQE_TCP_STATE_TIME_WAIT) ||
+		 (last_ae == NES_AEQE_AEID_RDMAP_ROE_BAD_LLP_CLOSE) ||
+		 (last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET))) {
+		issue_close = 1;
+		nesqp->cm_id = NULL;
+		if (nesqp->flush_issued == 0) {
+			nesqp->flush_issued = 1;
+			issue_flush = 1;
+		}
+	}
+
+	spin_unlock_irqrestore(&nesqp->lock, flags);
 
-	nes_debug(NES_DBG_CM, "set ibqp_state=%u\n", nesqp->ibqp_state);
+	if ((issue_flush) && (nesqp->destroyed == 0)) {
+		/* Flush the queue(s) */
+		if (nesqp->hw_iwarp_state >= NES_AEQE_IWARP_STATE_TERMINATE)
+			flush_q |= NES_CQP_FLUSH_SQ;
+		flush_wqes(nesvnic->nesdev, nesqp, flush_q, 1);
 
-	if ((nesqp->cm_id) && (cm_id->event_handler)) {
-		if ((original_hw_tcp_state == NES_AEQE_TCP_STATE_CLOSE_WAIT) ||
-				((original_ibqp_state == IB_QPS_RTS) &&
-				(last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET))) {
+		if (nesqp->term_flags) {
+			ibevent.device = nesqp->ibqp.device;
+			ibevent.event = nesqp->terminate_eventtype;
+			ibevent.element.qp = &nesqp->ibqp;
+			nesqp->ibqp.event_handler(&ibevent, nesqp->ibqp.qp_context);
+		}
+	}
+
+	if ((cm_id) && (cm_id->event_handler)) {
+		if (issue_disconn) {
 			atomic_inc(&cm_disconnects);
 			cm_event.event = IW_CM_EVENT_DISCONNECT;
-			if (last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET) {
-				cm_event.status = IW_CM_EVENT_STATUS_RESET;
-				nes_debug(NES_DBG_CM, "Generating a CM "
-					"Disconnect Event (status reset) for "
-					"QP%u, cm_id = %p. \n",
-					nesqp->hwqp.qp_id, cm_id);
-			} else
-				cm_event.status = IW_CM_EVENT_STATUS_OK;
-
+			cm_event.status = disconn_status;
 			cm_event.local_addr = cm_id->local_addr;
 			cm_event.remote_addr = cm_id->remote_addr;
 			cm_event.private_data = NULL;
@@ -2547,28 +2583,14 @@ static int nes_cm_disconn_true(struct nes_qp *nesqp)
 				nesqp->hwqp.sq_tail, cm_id,
 				atomic_read(&nesqp->refcount));
 
-			spin_unlock_irqrestore(&nesqp->lock, flags);
 			ret = cm_id->event_handler(cm_id, &cm_event);
 			if (ret)
 				nes_debug(NES_DBG_CM, "OFA CM event_handler "
 					"returned, ret=%d\n", ret);
-			spin_lock_irqsave(&nesqp->lock, flags);
 		}
 
-		/* There might have been another AE while the lock was released */
-		original_hw_tcp_state = nesqp->hw_tcp_state;
-		original_ibqp_state   = nesqp->ibqp_state;
-		last_ae = nesqp->last_aeq;
-
-		if ((issued_disconnect_reset == 0) && (nesqp->cm_id) &&
-				((original_hw_tcp_state == NES_AEQE_TCP_STATE_CLOSED) ||
-				 (original_hw_tcp_state == NES_AEQE_TCP_STATE_TIME_WAIT) ||
-				 (last_ae == NES_AEQE_AEID_RDMAP_ROE_BAD_LLP_CLOSE) ||
-				 (last_ae == NES_AEQE_AEID_LLP_CONNECTION_RESET))) {
+		if (issue_close) {
 			atomic_inc(&cm_closes);
-			nesqp->cm_id = NULL;
-			nesqp->in_disconnect = 0;
-			spin_unlock_irqrestore(&nesqp->lock, flags);
 			nes_disconnect(nesqp, 1);
 
 			cm_id->provider_data = nesqp;
@@ -2587,27 +2609,7 @@ static int nes_cm_disconn_true(struct nes_qp *nesqp)
 			}
 
 			cm_id->rem_ref(cm_id);
-
-			spin_lock_irqsave(&nesqp->lock, flags);
-			if (nesqp->flush_issued == 0) {
-				nesqp->flush_issued = 1;
-				spin_unlock_irqrestore(&nesqp->lock, flags);
-				flush_wqes(nesvnic->nesdev, nesqp,
-					NES_CQP_FLUSH_RQ, 1);
-			} else
-				spin_unlock_irqrestore(&nesqp->lock, flags);
-		} else {
-			cm_id = nesqp->cm_id;
-			spin_unlock_irqrestore(&nesqp->lock, flags);
-			/* check to see if the inbound reset beat the outbound reset */
-			if ((!cm_id) && (last_ae==NES_AEQE_AEID_RESET_SENT)) {
-				nes_debug(NES_DBG_CM, "QP%u: Decing refcount "
-					"due to inbound reset beating the "
-					"outbound reset.\n", nesqp->hwqp.qp_id);
-			}
 		}
-	} else {
-		spin_unlock_irqrestore(&nesqp->lock, flags);
 	}
 
 	return 0;