PCI: return correct value when writing to the "reset" attribute

commit 447c5dd7 upstream.

A successful write() to the "reset" sysfs attribute should return the
number of bytes written, not 0. Otherwise userspace (bash) retries the
write over and over again.
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Michal Schmidt <mschmidt@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/pci/pci-sysfs.c

@@ -939,7 +939,12 @@ static ssize_t reset_store(struct device *dev,
 
 	if (val != 1)
 		return -EINVAL;
-	return pci_reset_function(pdev);
+
+	result = pci_reset_function(pdev);
+	if (result < 0)
+		return result;
+
+	return count;
 }
 
 static struct device_attribute reset_attr = __ATTR(reset, 0200, NULL, reset_store);