s390/dasd: Add dasd_sleep_on_queue_interruptible()

There is dasd_sleep_on() and dasd_sleep_on_interruptible() to start CCW
requests uninterruptible and interruptible. However, there is only
dasd_sleep_on_queue() to start requests from CCW queues uninterruptible.

Add dasd_sleep_on_queue_interruptible() to provide a way to start
requests from CCW queues interruptible. _dasd_sleep_on_queue() already
provides this functionality.
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

drivers/s390/block/dasd.c

@@ -2522,6 +2522,15 @@ int dasd_sleep_on_queue(struct list_head *ccw_queue)
 }
 EXPORT_SYMBOL(dasd_sleep_on_queue);
 
+/*
+ * Start requests from a ccw_queue and wait interruptible for their completion.
+ */
+int dasd_sleep_on_queue_interruptible(struct list_head *ccw_queue)
+{
+	return _dasd_sleep_on_queue(ccw_queue, 1);
+}
+EXPORT_SYMBOL(dasd_sleep_on_queue_interruptible);
+
 /*
  * Queue a request to the tail of the device ccw_queue and wait
  * interruptible for it's completion.

drivers/s390/block/dasd_int.h

@@ -748,6 +748,7 @@ void dasd_schedule_block_bh(struct dasd_block *);
 int  dasd_sleep_on(struct dasd_ccw_req *);
 int  dasd_sleep_on_queue(struct list_head *);
 int  dasd_sleep_on_immediatly(struct dasd_ccw_req *);
+int  dasd_sleep_on_queue_interruptible(struct list_head *);
 int  dasd_sleep_on_interruptible(struct dasd_ccw_req *);
 void dasd_device_set_timer(struct dasd_device *, int);
 void dasd_device_clear_timer(struct dasd_device *);