[S390] cio: use exception-save stsch

Using stsch on schids with ssid != 0 can lead to an operand
exception. Use stsch_err to handle potential exceptions
if we fail to reenable mss after hibernation.

Cc: <stable@kernel.org>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

drivers/s390/cio/chsc_sch.c

@@ -124,7 +124,7 @@ static int chsc_subchannel_prepare(struct subchannel *sch)
 	 * since we don't have a way to clear the subchannel and
 	 * cannot disable it with a request running.
 	 */
-	cc = stsch(sch->schid, &schib);
+	cc = stsch_err(sch->schid, &schib);
 	if (!cc && scsw_stctl(&schib.scsw))
 		return -EAGAIN;
 	return 0;

drivers/s390/cio/cio.c

@@ -361,7 +361,7 @@ int cio_commit_config(struct subchannel *sch)
 	struct schib schib;
 	int ccode, retry, ret = 0;
 
-	if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+	if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib))
 		return -ENODEV;
 
 	for (retry = 0; retry < 5; retry++) {
@@ -372,7 +372,7 @@ int cio_commit_config(struct subchannel *sch)
 			return ccode;
 		switch (ccode) {
 		case 0: /* successful */
-			if (stsch(sch->schid, &schib) ||
+			if (stsch_err(sch->schid, &schib) ||
 			    !css_sch_is_valid(&schib))
 				return -ENODEV;
 			if (cio_check_config(sch, &schib)) {
@@ -404,7 +404,7 @@ int cio_update_schib(struct subchannel *sch)
 {
 	struct schib schib;
 
-	if (stsch(sch->schid, &schib) || !css_sch_is_valid(&schib))
+	if (stsch_err(sch->schid, &schib) || !css_sch_is_valid(&schib))
 		return -ENODEV;
 
 	memcpy(&sch->schib, &schib, sizeof(schib));
@@ -771,7 +771,7 @@ cio_get_console_sch_no(void)
 	if (console_irq != -1) {
 		/* VM provided us with the irq number of the console. */
 		schid.sch_no = console_irq;
-		if (stsch(schid, &console_subchannel.schib) != 0 ||
+		if (stsch_err(schid, &console_subchannel.schib) != 0 ||
 		    (console_subchannel.schib.pmcw.st != SUBCHANNEL_TYPE_IO) ||
 		    !console_subchannel.schib.pmcw.dnv)
 			return -1;
@@ -863,10 +863,10 @@ __disable_subchannel_easy(struct subchannel_id schid, struct schib *schib)
 	cc = 0;
 	for (retry=0;retry<3;retry++) {
 		schib->pmcw.ena = 0;
-		cc = msch(schid, schib);
+		cc = msch_err(schid, schib);
 		if (cc)
 			return (cc==3?-ENODEV:-EBUSY);
-		if (stsch(schid, schib) || !css_sch_is_valid(schib))
+		if (stsch_err(schid, schib) || !css_sch_is_valid(schib))
 			return -ENODEV;
 		if (!schib->pmcw.ena)
 			return 0;
@@ -913,7 +913,7 @@ static int stsch_reset(struct subchannel_id schid, struct schib *addr)
 
 	pgm_check_occured = 0;
 	s390_base_pgm_handler_fn = cio_reset_pgm_check_handler;
-	rc = stsch(schid, addr);
+	rc = stsch_err(schid, addr);
 	s390_base_pgm_handler_fn = NULL;
 
 	/* The program check handler could have changed pgm_check_occured. */
@@ -950,7 +950,7 @@ static int __shutdown_subchannel_easy(struct subchannel_id schid, void *data)
 			/* No default clear strategy */
 			break;
 		}
-		stsch(schid, &schib);
+		stsch_err(schid, &schib);
 		__disable_subchannel_easy(schid, &schib);
 	}
 out:
@@ -1086,7 +1086,7 @@ int __init cio_get_iplinfo(struct cio_iplinfo *iplinfo)
 	schid = *(struct subchannel_id *)&S390_lowcore.subchannel_id;
 	if (!schid.one)
 		return -ENODEV;
-	if (stsch(schid, &schib))
+	if (stsch_err(schid, &schib))
 		return -ENODEV;
 	if (schib.pmcw.st != SUBCHANNEL_TYPE_IO)
 		return -ENODEV;

drivers/s390/cio/device_fsm.c

@@ -45,7 +45,7 @@ static void ccw_timeout_log(struct ccw_device *cdev)
 	sch = to_subchannel(cdev->dev.parent);
 	private = to_io_private(sch);
 	orb = &private->orb;
-	cc = stsch(sch->schid, &schib);
+	cc = stsch_err(sch->schid, &schib);
 
 	printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
 	       "device information:\n", get_clock());