1 files changed, 108 insertions, 101 deletions

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index bc099b61394d..e2aa944eb566 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -36,7 +36,8 @@
 int css_init_done = 0;
 int max_ssid;
 
-struct channel_subsystem *channel_subsystems[__MAX_CSSID + 1];
+#define MAX_CSS_IDX 0
+struct channel_subsystem *channel_subsystems[MAX_CSS_IDX + 1];
 static struct bus_type css_bus_type;
 
 int
@@ -702,7 +703,8 @@ css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
 
 	if (css_general_characteristics.mcss) {
 		css->global_pgid.pgid_high.ext_cssid.version = 0x80;
-		css->global_pgid.pgid_high.ext_cssid.cssid = css->cssid;
+		css->global_pgid.pgid_high.ext_cssid.cssid =
+			(css->cssid < 0) ? 0 : css->cssid;
 	} else {
 		css->global_pgid.pgid_high.cpu_addr = stap();
 	}
@@ -712,43 +714,44 @@ css_generate_pgid(struct channel_subsystem *css, u32 tod_high)
 	css->global_pgid.tod_high = tod_high;
 }
 
-static void
-channel_subsystem_release(struct device *dev)
+static void channel_subsystem_release(struct device *dev)
 {
-	struct channel_subsystem *css;
+	struct channel_subsystem *css = to_css(dev);
 
-	css = to_css(dev);
 	mutex_destroy(&css->mutex);
-	if (css->pseudo_subchannel) {
-		/* Implies that it has been generated but never registered. */
-		css_subchannel_release(&css->pseudo_subchannel->dev);
-		css->pseudo_subchannel = NULL;
-	}
 	kfree(css);
 }
 
-static ssize_t
-css_cm_enable_show(struct device *dev, struct device_attribute *attr,
-		   char *buf)
+static ssize_t real_cssid_show(struct device *dev, struct device_attribute *a,
+			       char *buf)
+{
+	struct channel_subsystem *css = to_css(dev);
+
+	if (css->cssid < 0)
+		return -EINVAL;
+
+	return sprintf(buf, "%x\n", css->cssid);
+}
+static DEVICE_ATTR_RO(real_cssid);
+
+static ssize_t cm_enable_show(struct device *dev, struct device_attribute *a,
+			      char *buf)
 {
 	struct channel_subsystem *css = to_css(dev);
 	int ret;
 
-	if (!css)
-		return 0;
 	mutex_lock(&css->mutex);
 	ret = sprintf(buf, "%x\n", css->cm_enabled);
 	mutex_unlock(&css->mutex);
 	return ret;
 }
 
-static ssize_t
-css_cm_enable_store(struct device *dev, struct device_attribute *attr,
-		    const char *buf, size_t count)
+static ssize_t cm_enable_store(struct device *dev, struct device_attribute *a,
+			       const char *buf, size_t count)
 {
 	struct channel_subsystem *css = to_css(dev);
-	int ret;
 	unsigned long val;
+	int ret;
 
 	ret = kstrtoul(buf, 16, &val);
 	if (ret)
@@ -767,51 +770,104 @@ css_cm_enable_store(struct device *dev, struct device_attribute *attr,
 	mutex_unlock(&css->mutex);
 	return ret < 0 ? ret : count;
 }
+static DEVICE_ATTR_RW(cm_enable);
+
+static umode_t cm_enable_mode(struct kobject *kobj, struct attribute *attr,
+			      int index)
+{
+	return css_chsc_characteristics.secm ? attr->mode : 0;
+}
+
+static struct attribute *cssdev_attrs[] = {
+	&dev_attr_real_cssid.attr,
+	NULL,
+};
+
+static struct attribute_group cssdev_attr_group = {
+	.attrs = cssdev_attrs,
+};
+
+static struct attribute *cssdev_cm_attrs[] = {
+	&dev_attr_cm_enable.attr,
+	NULL,
+};
+
+static struct attribute_group cssdev_cm_attr_group = {
+	.attrs = cssdev_cm_attrs,
+	.is_visible = cm_enable_mode,
+};
 
-static DEVICE_ATTR(cm_enable, 0644, css_cm_enable_show, css_cm_enable_store);
+static const struct attribute_group *cssdev_attr_groups[] = {
+	&cssdev_attr_group,
+	&cssdev_cm_attr_group,
+	NULL,
+};
 
 static int __init setup_css(int nr)
 {
-	u32 tod_high;
-	int ret;
 	struct channel_subsystem *css;
+	int ret;
 
-	css = channel_subsystems[nr];
-	memset(css, 0, sizeof(struct channel_subsystem));
-	css->pseudo_subchannel =
-		kzalloc(sizeof(*css->pseudo_subchannel), GFP_KERNEL);
-	if (!css->pseudo_subchannel)
+	css = kzalloc(sizeof(*css), GFP_KERNEL);
+	if (!css)
 		return -ENOMEM;
+
+	channel_subsystems[nr] = css;
+	dev_set_name(&css->device, "css%x", nr);
+	css->device.groups = cssdev_attr_groups;
+	css->device.release = channel_subsystem_release;
+
+	mutex_init(&css->mutex);
+	css->cssid = chsc_get_cssid(nr);
+	css_generate_pgid(css, (u32) (get_tod_clock() >> 32));
+
+	ret = device_register(&css->device);
+	if (ret) {
+		put_device(&css->device);
+		goto out_err;
+	}
+
+	css->pseudo_subchannel = kzalloc(sizeof(*css->pseudo_subchannel),
+					 GFP_KERNEL);
+	if (!css->pseudo_subchannel) {
+		device_unregister(&css->device);
+		ret = -ENOMEM;
+		goto out_err;
+	}
+
 	css->pseudo_subchannel->dev.parent = &css->device;
 	css->pseudo_subchannel->dev.release = css_subchannel_release;
-	dev_set_name(&css->pseudo_subchannel->dev, "defunct");
 	mutex_init(&css->pseudo_subchannel->reg_mutex);
 	ret = css_sch_create_locks(css->pseudo_subchannel);
 	if (ret) {
 		kfree(css->pseudo_subchannel);
-		return ret;
+		device_unregister(&css->device);
+		goto out_err;
 	}
-	mutex_init(&css->mutex);
-	css->valid = 1;
-	css->cssid = nr;
-	dev_set_name(&css->device, "css%x", nr);
-	css->device.release = channel_subsystem_release;
-	tod_high = (u32) (get_tod_clock() >> 32);
-	css_generate_pgid(css, tod_high);
-	return 0;
+
+	dev_set_name(&css->pseudo_subchannel->dev, "defunct");
+	ret = device_register(&css->pseudo_subchannel->dev);
+	if (ret) {
+		put_device(&css->pseudo_subchannel->dev);
+		device_unregister(&css->device);
+		goto out_err;
+	}
+
+	return ret;
+out_err:
+	channel_subsystems[nr] = NULL;
+	return ret;
 }
 
 static int css_reboot_event(struct notifier_block *this,
 			    unsigned long event,
 			    void *ptr)
 {
-	int ret, i;
+	struct channel_subsystem *css;
+	int ret;
 
 	ret = NOTIFY_DONE;
-	for (i = 0; i <= __MAX_CSSID; i++) {
-		struct channel_subsystem *css;
-
-		css = channel_subsystems[i];
+	for_each_css(css) {
 		mutex_lock(&css->mutex);
 		if (css->cm_enabled)
 			if (chsc_secm(css, 0))
@@ -835,16 +891,14 @@ static struct notifier_block css_reboot_notifier = {
 static int css_power_event(struct notifier_block *this, unsigned long event,
 			   void *ptr)
 {
-	int ret, i;
+	struct channel_subsystem *css;
+	int ret;
 
 	switch (event) {
 	case PM_HIBERNATION_PREPARE:
 	case PM_SUSPEND_PREPARE:
 		ret = NOTIFY_DONE;
-		for (i = 0; i <= __MAX_CSSID; i++) {
-			struct channel_subsystem *css;
-
-			css = channel_subsystems[i];
+		for_each_css(css) {
 			mutex_lock(&css->mutex);
 			if (!css->cm_enabled) {
 				mutex_unlock(&css->mutex);
@@ -858,10 +912,7 @@ static int css_power_event(struct notifier_block *this, unsigned long event,
 	case PM_POST_HIBERNATION:
 	case PM_POST_SUSPEND:
 		ret = NOTIFY_DONE;
-		for (i = 0; i <= __MAX_CSSID; i++) {
-			struct channel_subsystem *css;
-
-			css = channel_subsystems[i];
+		for_each_css(css) {
 			mutex_lock(&css->mutex);
 			if (!css->cm_enabled) {
 				mutex_unlock(&css->mutex);
@@ -916,36 +967,10 @@ static int __init css_bus_init(void)
 		goto out;
 
 	/* Setup css structure. */
-	for (i = 0; i <= __MAX_CSSID; i++) {
-		struct channel_subsystem *css;
-
-		css = kmalloc(sizeof(struct channel_subsystem), GFP_KERNEL);
-		if (!css) {
-			ret = -ENOMEM;
-			goto out_unregister;
-		}
-		channel_subsystems[i] = css;
+	for (i = 0; i <= MAX_CSS_IDX; i++) {
 		ret = setup_css(i);
-		if (ret) {
-			kfree(channel_subsystems[i]);
-			goto out_unregister;
-		}
-		ret = device_register(&css->device);
-		if (ret) {
-			put_device(&css->device);
+		if (ret)
 			goto out_unregister;
-		}
-		if (css_chsc_characteristics.secm) {
-			ret = device_create_file(&css->device,
-						 &dev_attr_cm_enable);
-			if (ret)
-				goto out_device;
-		}
-		ret = device_register(&css->pseudo_subchannel->dev);
-		if (ret) {
-			put_device(&css->pseudo_subchannel->dev);
-			goto out_file;
-		}
 	}
 	ret = register_reboot_notifier(&css_reboot_notifier);
 	if (ret)
@@ -961,23 +986,10 @@ static int __init css_bus_init(void)
 	isc_register(IO_SCH_ISC);
 
 	return 0;
-out_file:
-	if (css_chsc_characteristics.secm)
-		device_remove_file(&channel_subsystems[i]->device,
-				   &dev_attr_cm_enable);
-out_device:
-	device_unregister(&channel_subsystems[i]->device);
 out_unregister:
-	while (i > 0) {
-		struct channel_subsystem *css;
-
-		i--;
-		css = channel_subsystems[i];
+	while (i-- > 0) {
+		struct channel_subsystem *css = channel_subsystems[i];
 		device_unregister(&css->pseudo_subchannel->dev);
-		css->pseudo_subchannel = NULL;
-		if (css_chsc_characteristics.secm)
-			device_remove_file(&css->device,
-					   &dev_attr_cm_enable);
 		device_unregister(&css->device);
 	}
 	bus_unregister(&css_bus_type);
@@ -993,14 +1005,9 @@ out:
 static void __init css_bus_cleanup(void)
 {
 	struct channel_subsystem *css;
-	int i;
 
-	for (i = 0; i <= __MAX_CSSID; i++) {
-		css = channel_subsystems[i];
+	for_each_css(css) {
 		device_unregister(&css->pseudo_subchannel->dev);
-		css->pseudo_subchannel = NULL;
-		if (css_chsc_characteristics.secm)
-			device_remove_file(&css->device, &dev_attr_cm_enable);
 		device_unregister(&css->device);
 	}
 	bus_unregister(&css_bus_type);