1 files changed, 27 insertions, 5 deletions

diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c
index 5d17149..c6fab5d 100644
--- a/drivers/s390/char/tape_core.c
+++ b/drivers/s390/char/tape_core.c
@@ -761,6 +761,13 @@ __tape_start_next_request(struct tape_device *device)
 		 */
 		if (request->status == TAPE_REQUEST_IN_IO)
 			return;
+		/*
+		 * Request has already been stopped. We have to wait until
+		 * the request is removed from the queue in the interrupt
+		 * handling.
+		 */
+		if (request->status == TAPE_REQUEST_DONE)
+			return;
 
 		/*
 		 * We wanted to cancel the request but the common I/O layer
@@ -1024,6 +1031,20 @@ tape_do_io_interruptible(struct tape_device *device,
 }
 
 /*
+ * Stop running ccw.
+ */
+int
+tape_cancel_io(struct tape_device *device, struct tape_request *request)
+{
+	int rc;
+
+	spin_lock_irq(get_ccwdev_lock(device->cdev));
+	rc = __tape_cancel_io(device, request);
+	spin_unlock_irq(get_ccwdev_lock(device->cdev));
+	return rc;
+}
+
+/*
  * Tape interrupt routine, called from the ccw_device layer
  */
 static void
@@ -1068,12 +1089,12 @@ __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
 	 * error might still apply. So we just schedule the request to be
 	 * started later.
 	 */
-	if (irb->scsw.cc != 0 && (irb->scsw.fctl & SCSW_FCTL_START_FUNC)) {
-		PRINT_WARN("(%s): deferred cc=%i. restaring\n",
-			cdev->dev.bus_id,
-			irb->scsw.cc);
+	if (irb->scsw.cc != 0 && (irb->scsw.fctl & SCSW_FCTL_START_FUNC) &&
+	    (request->status == TAPE_REQUEST_IN_IO)) {
+		DBF_EVENT(3,"(%08x): deferred cc=%i, fctl=%i. restarting\n",
+			device->cdev_id, irb->scsw.cc, irb->scsw.fctl);
 		request->status = TAPE_REQUEST_QUEUED;
-		schedule_work(&device->tape_dnr);
+		schedule_delayed_work(&device->tape_dnr, HZ);
 		return;
 	}
 
@@ -1287,4 +1308,5 @@ EXPORT_SYMBOL(tape_dump_sense_dbf);
 EXPORT_SYMBOL(tape_do_io);
 EXPORT_SYMBOL(tape_do_io_async);
 EXPORT_SYMBOL(tape_do_io_interruptible);
+EXPORT_SYMBOL(tape_cancel_io);
 EXPORT_SYMBOL(tape_mtop);