s390/qeth: return error when starting a reset fails

When starting the reset worker via sysfs is unsuccessful, return an
error to the user.
Modernize the sysfs input parsing while at it.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/s390/net/qeth_core.h

@@ -1053,7 +1053,7 @@ struct qeth_cmd_buffer *qeth_get_diag_cmd(struct qeth_card *card,
 void qeth_notify_cmd(struct qeth_cmd_buffer *iob, int reason);
 void qeth_put_cmd(struct qeth_cmd_buffer *iob);
 
-void qeth_schedule_recovery(struct qeth_card *);
+int qeth_schedule_recovery(struct qeth_card *card);
 void qeth_flush_local_addrs(struct qeth_card *card);
 int qeth_poll(struct napi_struct *napi, int budget);
 void qeth_clear_ipacmd_list(struct qeth_card *);

drivers/s390/net/qeth_core_main.c

@@ -1131,16 +1131,18 @@ static int qeth_set_thread_start_bit(struct qeth_card *card,
 		unsigned long thread)
 {
 	unsigned long flags;
+	int rc = 0;
 
 	spin_lock_irqsave(&card->thread_mask_lock, flags);
-	if (!(card->thread_allowed_mask & thread) ||
-	      (card->thread_start_mask & thread)) {
-		spin_unlock_irqrestore(&card->thread_mask_lock, flags);
-		return -EPERM;
-	}
-	card->thread_start_mask |= thread;
+	if (!(card->thread_allowed_mask & thread))
+		rc = -EPERM;
+	else if (card->thread_start_mask & thread)
+		rc = -EBUSY;
+	else
+		card->thread_start_mask |= thread;
 	spin_unlock_irqrestore(&card->thread_mask_lock, flags);
-	return 0;
+
+	return rc;
 }
 
 static void qeth_clear_thread_start_bit(struct qeth_card *card,
@@ -1193,11 +1195,17 @@ static int qeth_do_run_thread(struct qeth_card *card, unsigned long thread)
 	return rc;
 }
 
-void qeth_schedule_recovery(struct qeth_card *card)
+int qeth_schedule_recovery(struct qeth_card *card)
 {
+	int rc;
+
 	QETH_CARD_TEXT(card, 2, "startrec");
-	if (qeth_set_thread_start_bit(card, QETH_RECOVER_THREAD) == 0)
+
+	rc = qeth_set_thread_start_bit(card, QETH_RECOVER_THREAD);
+	if (!rc)
 		schedule_work(&card->kernel_thread_starter);
+
+	return rc;
 }
 
 static int qeth_get_problem(struct qeth_card *card, struct ccw_device *cdev,

drivers/s390/net/qeth_core_sys.c

@@ -275,17 +275,20 @@ static ssize_t qeth_dev_recover_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct qeth_card *card = dev_get_drvdata(dev);
-	char *tmp;
-	int i;
+	bool reset;
+	int rc;
+
+	rc = kstrtobool(buf, &reset);
+	if (rc)
+		return rc;
 
 	if (!qeth_card_hw_is_reachable(card))
 		return -EPERM;
 
-	i = simple_strtoul(buf, &tmp, 16);
-	if (i == 1)
-		qeth_schedule_recovery(card);
+	if (reset)
+		rc = qeth_schedule_recovery(card);
 
-	return count;
+	return rc ? rc : count;
 }
 
 static DEVICE_ATTR(recover, 0200, NULL, qeth_dev_recover_store);