[SCSI] zfcp: Replace fsf_req wait_queue with completion

The combination wait_queue/wakeup in conjunction with the flag
ZFCP_STATUS_FSFREQ_COMPLETED to signal the completion of an fsfreq
was not race-safe and can be better solved by a completion.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
diff --git a/drivers/s390/scsi/zfcp_scsi.c b/drivers/s390/scsi/zfcp_scsi.c
index 0bd80a9..0de0591 100644
--- a/drivers/s390/scsi/zfcp_scsi.c
+++ b/drivers/s390/scsi/zfcp_scsi.c
@@ -206,8 +206,7 @@
 	if (!abrt_req)
 		return FAILED;
 
-	wait_event(abrt_req->completion_wq,
-		   abrt_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
+	wait_for_completion(&abrt_req->completion);
 
 	if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED)
 		dbf_tag = "okay";
@@ -246,8 +245,7 @@
 	if (!fsf_req)
 		return FAILED;
 
-	wait_event(fsf_req->completion_wq,
-		   fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
+	wait_for_completion(&fsf_req->completion);
 
 	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
 		zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);