IB/srp: Handle DREQ events from CM

Handle IB_CM_DREQ_ERROR and IB_CM_DREQ_RECEIVED events from the CM,
instead of just printing "Unhandled CM event".  In the case of
DREQ_ERROR, just ignore the event -- a TIMEWAIT_EXIT will be generated
also.  For DREQ_RECEIVED, send a DREP in response to shut the
connection down cleanly.
Signed-off-by: Ishai Rabinovitz <ishai@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/ulp/srp/ib_srp.c

@@ -1196,11 +1196,10 @@ static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 		srp_cm_rej_handler(cm_id, event, target);
 		break;
 
-	case IB_CM_MRA_RECEIVED:
-		printk(KERN_ERR PFX "MRA received\n");
-		break;
-
-	case IB_CM_DREP_RECEIVED:
+	case IB_CM_DREQ_RECEIVED:
+		printk(KERN_WARNING PFX "DREQ received - connection closed\n");
+		if (ib_send_cm_drep(cm_id, NULL, 0))
+			printk(KERN_ERR PFX "Sending CM DREP failed\n");
 		break;
 
 	case IB_CM_TIMEWAIT_EXIT:
@@ -1210,6 +1209,11 @@ static int srp_cm_handler(struct ib_cm_id *cm_id, struct ib_cm_event *event)
 		target->status = 0;
 		break;
 
+	case IB_CM_MRA_RECEIVED:
+	case IB_CM_DREQ_ERROR:
+	case IB_CM_DREP_RECEIVED:
+		break;
+
 	default:
 		printk(KERN_WARNING PFX "Unhandled CM event %d\n", event->event);
 		break;