[S390] dasd: re-initialize read_conf buffer for retries

The buffer for read configuration data has to be initialized with an
EBCDIC string to show support for extended UIDs to z/VM.
If this read configuration data CQR needs to be retried, the buffer
may have changed in between. So re-initialize the buffer to get a
correct extended UID under z/VM.

Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 3b94b6542fc0..ce2a780a9ea8 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -2059,13 +2059,14 @@ void dasd_add_request_tail(struct dasd_ccw_req *cqr)
 /*
  * Wakeup helper for the 'sleep_on' functions.
  */
-static void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
+void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
 {
         spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
         cqr->callback_data = DASD_SLEEPON_END_TAG;
         spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
         wake_up(&generic_waitq);
 }
+EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
 
 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
 {
@@ -2165,7 +2166,9 @@ static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
                 } else
                         wait_event(generic_waitq, !(device->stopped));
 
-                cqr->callback = dasd_wakeup_cb;
+                if (!cqr->callback)
+                        cqr->callback = dasd_wakeup_cb;
+
                 cqr->callback_data = DASD_SLEEPON_START_TAG;
                 dasd_add_request_tail(cqr);
                 if (interruptible) {