1 files changed, 248 insertions, 85 deletions

diff --git a/drivers/base/class.c b/drivers/base/class.c
index cc5e28c8885..f96f70419a7 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -27,11 +27,11 @@ static ssize_t class_attr_show(struct kobject *kobj, struct attribute *attr,
 			       char *buf)
 {
 	struct class_attribute *class_attr = to_class_attr(attr);
-	struct class_private *cp = to_class(kobj);
+	struct subsys_private *cp = to_subsys_private(kobj);
 	ssize_t ret = -EIO;
 
 	if (class_attr->show)
-		ret = class_attr->show(cp->class, buf);
+		ret = class_attr->show(cp->class, class_attr, buf);
 	return ret;
 }
 
@@ -39,17 +39,17 @@ static ssize_t class_attr_store(struct kobject *kobj, struct attribute *attr,
 				const char *buf, size_t count)
 {
 	struct class_attribute *class_attr = to_class_attr(attr);
-	struct class_private *cp = to_class(kobj);
+	struct subsys_private *cp = to_subsys_private(kobj);
 	ssize_t ret = -EIO;
 
 	if (class_attr->store)
-		ret = class_attr->store(cp->class, buf, count);
+		ret = class_attr->store(cp->class, class_attr, buf, count);
 	return ret;
 }
 
 static void class_release(struct kobject *kobj)
 {
-	struct class_private *cp = to_class(kobj);
+	struct subsys_private *cp = to_subsys_private(kobj);
 	struct class *class = cp->class;
 
 	pr_debug("class '%s': release.\n", class->name);
@@ -59,50 +59,63 @@ static void class_release(struct kobject *kobj)
 	else
 		pr_debug("class '%s' does not have a release() function, "
 			 "be careful\n", class->name);
+
+	kfree(cp);
+}
+
+static const struct kobj_ns_type_operations *class_child_ns_type(struct kobject *kobj)
+{
+	struct subsys_private *cp = to_subsys_private(kobj);
+	struct class *class = cp->class;
+
+	return class->ns_type;
 }
 
-static struct sysfs_ops class_sysfs_ops = {
-	.show	= class_attr_show,
-	.store	= class_attr_store,
+static const struct sysfs_ops class_sysfs_ops = {
+	.show	   = class_attr_show,
+	.store	   = class_attr_store,
 };
 
 static struct kobj_type class_ktype = {
 	.sysfs_ops	= &class_sysfs_ops,
 	.release	= class_release,
+	.child_ns_type	= class_child_ns_type,
 };
 
-/* Hotplug events for classes go to the class class_subsys */
+/* Hotplug events for classes go to the class subsys */
 static struct kset *class_kset;
 
 
-int class_create_file(struct class *cls, const struct class_attribute *attr)
+int class_create_file_ns(struct class *cls, const struct class_attribute *attr,
+			 const void *ns)
 {
 	int error;
 	if (cls)
-		error = sysfs_create_file(&cls->p->class_subsys.kobj,
-					  &attr->attr);
+		error = sysfs_create_file_ns(&cls->p->subsys.kobj,
+					     &attr->attr, ns);
 	else
 		error = -EINVAL;
 	return error;
 }
 
-void class_remove_file(struct class *cls, const struct class_attribute *attr)
+void class_remove_file_ns(struct class *cls, const struct class_attribute *attr,
+			  const void *ns)
 {
 	if (cls)
-		sysfs_remove_file(&cls->p->class_subsys.kobj, &attr->attr);
+		sysfs_remove_file_ns(&cls->p->subsys.kobj, &attr->attr, ns);
 }
 
 static struct class *class_get(struct class *cls)
 {
 	if (cls)
-		kset_get(&cls->p->class_subsys);
+		kset_get(&cls->p->subsys);
 	return cls;
 }
 
 static void class_put(struct class *cls)
 {
 	if (cls)
-		kset_put(&cls->p->class_subsys);
+		kset_put(&cls->p->subsys);
 }
 
 static int add_class_attrs(struct class *cls)
@@ -111,7 +124,7 @@ static int add_class_attrs(struct class *cls)
 	int error = 0;
 
 	if (cls->class_attrs) {
-		for (i = 0; attr_name(cls->class_attrs[i]); i++) {
+		for (i = 0; cls->class_attrs[i].attr.name; i++) {
 			error = class_create_file(cls, &cls->class_attrs[i]);
 			if (error)
 				goto error;
@@ -130,14 +143,28 @@ static void remove_class_attrs(struct class *cls)
 	int i;
 
 	if (cls->class_attrs) {
-		for (i = 0; attr_name(cls->class_attrs[i]); i++)
+		for (i = 0; cls->class_attrs[i].attr.name; i++)
 			class_remove_file(cls, &cls->class_attrs[i]);
 	}
 }
 
+static void klist_class_dev_get(struct klist_node *n)
+{
+	struct device *dev = container_of(n, struct device, knode_class);
+
+	get_device(dev);
+}
+
+static void klist_class_dev_put(struct klist_node *n)
+{
+	struct device *dev = container_of(n, struct device, knode_class);
+
+	put_device(dev);
+}
+
 int __class_register(struct class *cls, struct lock_class_key *key)
 {
-	struct class_private *cp;
+	struct subsys_private *cp;
 	int error;
 
 	pr_debug("device class '%s': registering\n", cls->name);
@@ -145,11 +172,11 @@ int __class_register(struct class *cls, struct lock_class_key *key)
 	cp = kzalloc(sizeof(*cp), GFP_KERNEL);
 	if (!cp)
 		return -ENOMEM;
-	INIT_LIST_HEAD(&cp->class_devices);
-	INIT_LIST_HEAD(&cp->class_interfaces);
-	kset_init(&cp->class_dirs);
-	__mutex_init(&cp->class_mutex, "struct class mutex", key);
-	error = kobject_set_name(&cp->class_subsys.kobj, "%s", cls->name);
+	klist_init(&cp->klist_devices, klist_class_dev_get, klist_class_dev_put);
+	INIT_LIST_HEAD(&cp->interfaces);
+	kset_init(&cp->glue_dirs);
+	__mutex_init(&cp->mutex, "subsys mutex", key);
+	error = kobject_set_name(&cp->subsys.kobj, "%s", cls->name);
 	if (error) {
 		kfree(cp);
 		return error;
@@ -159,18 +186,18 @@ int __class_register(struct class *cls, struct lock_class_key *key)
 	if (!cls->dev_kobj)
 		cls->dev_kobj = sysfs_dev_char_kobj;
 
-#if defined(CONFIG_SYSFS_DEPRECATED) && defined(CONFIG_BLOCK)
+#if defined(CONFIG_BLOCK)
 	/* let the block class directory show up in the root of sysfs */
-	if (cls != &block_class)
-		cp->class_subsys.kobj.kset = class_kset;
+	if (!sysfs_deprecated || cls != &block_class)
+		cp->subsys.kobj.kset = class_kset;
 #else
-	cp->class_subsys.kobj.kset = class_kset;
+	cp->subsys.kobj.kset = class_kset;
 #endif
-	cp->class_subsys.kobj.ktype = &class_ktype;
+	cp->subsys.kobj.ktype = &class_ktype;
 	cp->class = cls;
 	cls->p = cp;
 
-	error = kset_register(&cp->class_subsys);
+	error = kset_register(&cp->subsys);
 	if (error) {
 		kfree(cp);
 		return error;
@@ -185,7 +212,7 @@ void class_unregister(struct class *cls)
 {
 	pr_debug("device class '%s': unregistering\n", cls->name);
 	remove_class_attrs(cls);
-	kset_unregister(&cls->p->class_subsys);
+	kset_unregister(&cls->p->subsys);
 }
 
 static void class_create_release(struct class *cls)
@@ -203,6 +230,8 @@ static void class_create_release(struct class *cls)
  * This is used to create a struct class pointer that can then be used
  * in calls to device_create().
  *
+ * Returns &struct class pointer on success, or ERR_PTR() on error.
+ *
  * Note, the pointer created here is to be destroyed when finished by
  * making a call to class_destroy().
  */
@@ -249,24 +278,70 @@ void class_destroy(struct class *cls)
 	class_unregister(cls);
 }
 
-#ifdef CONFIG_SYSFS_DEPRECATED
-char *make_class_name(const char *name, struct kobject *kobj)
+/**
+ * class_dev_iter_init - initialize class device iterator
+ * @iter: class iterator to initialize
+ * @class: the class we wanna iterate over
+ * @start: the device to start iterating from, if any
+ * @type: device_type of the devices to iterate over, NULL for all
+ *
+ * Initialize class iterator @iter such that it iterates over devices
+ * of @class.  If @start is set, the list iteration will start there,
+ * otherwise if it is NULL, the iteration starts at the beginning of
+ * the list.
+ */
+void class_dev_iter_init(struct class_dev_iter *iter, struct class *class,
+			 struct device *start, const struct device_type *type)
 {
-	char *class_name;
-	int size;
+	struct klist_node *start_knode = NULL;
 
-	size = strlen(name) + strlen(kobject_name(kobj)) + 2;
+	if (start)
+		start_knode = &start->knode_class;
+	klist_iter_init_node(&class->p->klist_devices, &iter->ki, start_knode);
+	iter->type = type;
+}
+EXPORT_SYMBOL_GPL(class_dev_iter_init);
 
-	class_name = kmalloc(size, GFP_KERNEL);
-	if (!class_name)
-		return NULL;
+/**
+ * class_dev_iter_next - iterate to the next device
+ * @iter: class iterator to proceed
+ *
+ * Proceed @iter to the next device and return it.  Returns NULL if
+ * iteration is complete.
+ *
+ * The returned device is referenced and won't be released till
+ * iterator is proceed to the next device or exited.  The caller is
+ * free to do whatever it wants to do with the device including
+ * calling back into class code.
+ */
+struct device *class_dev_iter_next(struct class_dev_iter *iter)
+{
+	struct klist_node *knode;
+	struct device *dev;
 
-	strcpy(class_name, name);
-	strcat(class_name, ":");
-	strcat(class_name, kobject_name(kobj));
-	return class_name;
+	while (1) {
+		knode = klist_next(&iter->ki);
+		if (!knode)
+			return NULL;
+		dev = container_of(knode, struct device, knode_class);
+		if (!iter->type || iter->type == dev->type)
+			return dev;
+	}
 }
-#endif
+EXPORT_SYMBOL_GPL(class_dev_iter_next);
+
+/**
+ * class_dev_iter_exit - finish iteration
+ * @iter: class iterator to finish
+ *
+ * Finish an iteration.  Always call this function after iteration is
+ * complete whether the iteration ran till the end or not.
+ */
+void class_dev_iter_exit(struct class_dev_iter *iter)
+{
+	klist_iter_exit(&iter->ki);
+}
+EXPORT_SYMBOL_GPL(class_dev_iter_exit);
 
 /**
  * class_for_each_device - device iterator
@@ -283,13 +358,13 @@ char *make_class_name(const char *name, struct kobject *kobj)
  * We check the return of @fn each time. If it returns anything
  * other than 0, we break out and return that value.
  *
- * Note, we hold class->class_mutex in this function, so it can not be
- * re-acquired in @fn, otherwise it will self-deadlocking. For
- * example, calls to add or remove class members would be verboten.
+ * @fn is allowed to do anything including calling back into class
+ * code.  There's no locking restriction.
  */
 int class_for_each_device(struct class *class, struct device *start,
 			  void *data, int (*fn)(struct device *, void *))
 {
+	struct class_dev_iter iter;
 	struct device *dev;
 	int error = 0;
 
@@ -301,20 +376,13 @@ int class_for_each_device(struct class *class, struct device *start,
 		return -EINVAL;
 	}
 
-	mutex_lock(&class->p->class_mutex);
-	list_for_each_entry(dev, &class->p->class_devices, node) {
-		if (start) {
-			if (start == dev)
-				start = NULL;
-			continue;
-		}
-		dev = get_device(dev);
+	class_dev_iter_init(&iter, class, start, NULL);
+	while ((dev = class_dev_iter_next(&iter))) {
 		error = fn(dev, data);
-		put_device(dev);
 		if (error)
 			break;
 	}
-	mutex_unlock(&class->p->class_mutex);
+	class_dev_iter_exit(&iter);
 
 	return error;
 }
@@ -337,16 +405,15 @@ EXPORT_SYMBOL_GPL(class_for_each_device);
  *
  * Note, you will need to drop the reference with put_device() after use.
  *
- * We hold class->class_mutex in this function, so it can not be
- * re-acquired in @match, otherwise it will self-deadlocking. For
- * example, calls to add or remove class members would be verboten.
+ * @fn is allowed to do anything including calling back into class
+ * code.  There's no locking restriction.
  */
 struct device *class_find_device(struct class *class, struct device *start,
-				 void *data,
-				 int (*match)(struct device *, void *))
+				 const void *data,
+				 int (*match)(struct device *, const void *))
 {
+	struct class_dev_iter iter;
 	struct device *dev;
-	int found = 0;
 
 	if (!class)
 		return NULL;
@@ -356,29 +423,23 @@ struct device *class_find_device(struct class *class, struct device *start,
 		return NULL;
 	}
 
-	mutex_lock(&class->p->class_mutex);
-	list_for_each_entry(dev, &class->p->class_devices, node) {
-		if (start) {
-			if (start == dev)
-				start = NULL;
-			continue;
-		}
-		dev = get_device(dev);
+	class_dev_iter_init(&iter, class, start, NULL);
+	while ((dev = class_dev_iter_next(&iter))) {
 		if (match(dev, data)) {
-			found = 1;
+			get_device(dev);
 			break;
-		} else
-			put_device(dev);
+		}
 	}
-	mutex_unlock(&class->p->class_mutex);
+	class_dev_iter_exit(&iter);
 
-	return found ? dev : NULL;
+	return dev;
 }
 EXPORT_SYMBOL_GPL(class_find_device);
 
 int class_interface_register(struct class_interface *class_intf)
 {
 	struct class *parent;
+	struct class_dev_iter iter;
 	struct device *dev;
 
 	if (!class_intf || !class_intf->class)
@@ -388,13 +449,15 @@ int class_interface_register(struct class_interface *class_intf)
 	if (!parent)
 		return -EINVAL;
 
-	mutex_lock(&parent->p->class_mutex);
-	list_add_tail(&class_intf->node, &parent->p->class_interfaces);
+	mutex_lock(&parent->p->mutex);
+	list_add_tail(&class_intf->node, &parent->p->interfaces);
 	if (class_intf->add_dev) {
-		list_for_each_entry(dev, &parent->p->class_devices, node)
+		class_dev_iter_init(&iter, parent, NULL, NULL);
+		while ((dev = class_dev_iter_next(&iter)))
 			class_intf->add_dev(dev, class_intf);
+		class_dev_iter_exit(&iter);
 	}
-	mutex_unlock(&parent->p->class_mutex);
+	mutex_unlock(&parent->p->mutex);
 
 	return 0;
 }
@@ -402,22 +465,122 @@ int class_interface_register(struct class_interface *class_intf)
 void class_interface_unregister(struct class_interface *class_intf)
 {
 	struct class *parent = class_intf->class;
+	struct class_dev_iter iter;
 	struct device *dev;
 
 	if (!parent)
 		return;
 
-	mutex_lock(&parent->p->class_mutex);
+	mutex_lock(&parent->p->mutex);
 	list_del_init(&class_intf->node);
 	if (class_intf->remove_dev) {
-		list_for_each_entry(dev, &parent->p->class_devices, node)
+		class_dev_iter_init(&iter, parent, NULL, NULL);
+		while ((dev = class_dev_iter_next(&iter)))
 			class_intf->remove_dev(dev, class_intf);
+		class_dev_iter_exit(&iter);
 	}
-	mutex_unlock(&parent->p->class_mutex);
+	mutex_unlock(&parent->p->mutex);
 
 	class_put(parent);
 }
 
+ssize_t show_class_attr_string(struct class *class,
+			       struct class_attribute *attr, char *buf)
+{
+	struct class_attribute_string *cs;
+	cs = container_of(attr, struct class_attribute_string, attr);
+	return snprintf(buf, PAGE_SIZE, "%s\n", cs->str);
+}
+
+EXPORT_SYMBOL_GPL(show_class_attr_string);
+
+struct class_compat {
+	struct kobject *kobj;
+};
+
+/**
+ * class_compat_register - register a compatibility class
+ * @name: the name of the class
+ *
+ * Compatibility class are meant as a temporary user-space compatibility
+ * workaround when converting a family of class devices to a bus devices.
+ */
+struct class_compat *class_compat_register(const char *name)
+{
+	struct class_compat *cls;
+
+	cls = kmalloc(sizeof(struct class_compat), GFP_KERNEL);
+	if (!cls)
+		return NULL;
+	cls->kobj = kobject_create_and_add(name, &class_kset->kobj);
+	if (!cls->kobj) {
+		kfree(cls);
+		return NULL;
+	}
+	return cls;
+}
+EXPORT_SYMBOL_GPL(class_compat_register);
+
+/**
+ * class_compat_unregister - unregister a compatibility class
+ * @cls: the class to unregister
+ */
+void class_compat_unregister(struct class_compat *cls)
+{
+	kobject_put(cls->kobj);
+	kfree(cls);
+}
+EXPORT_SYMBOL_GPL(class_compat_unregister);
+
+/**
+ * class_compat_create_link - create a compatibility class device link to
+ *			      a bus device
+ * @cls: the compatibility class
+ * @dev: the target bus device
+ * @device_link: an optional device to which a "device" link should be created
+ */
+int class_compat_create_link(struct class_compat *cls, struct device *dev,
+			     struct device *device_link)
+{
+	int error;
+
+	error = sysfs_create_link(cls->kobj, &dev->kobj, dev_name(dev));
+	if (error)
+		return error;
+
+	/*
+	 * Optionally add a "device" link (typically to the parent), as a
+	 * class device would have one and we want to provide as much
+	 * backwards compatibility as possible.
+	 */
+	if (device_link) {
+		error = sysfs_create_link(&dev->kobj, &device_link->kobj,
+					  "device");
+		if (error)
+			sysfs_remove_link(cls->kobj, dev_name(dev));
+	}
+
+	return error;
+}
+EXPORT_SYMBOL_GPL(class_compat_create_link);
+
+/**
+ * class_compat_remove_link - remove a compatibility class device link to
+ *			      a bus device
+ * @cls: the compatibility class
+ * @dev: the target bus device
+ * @device_link: an optional device to which a "device" link was previously
+ * 		 created
+ */
+void class_compat_remove_link(struct class_compat *cls, struct device *dev,
+			      struct device *device_link)
+{
+	if (device_link)
+		sysfs_remove_link(&dev->kobj, "device");
+	sysfs_remove_link(cls->kobj, dev_name(dev));
+}
+EXPORT_SYMBOL_GPL(class_compat_remove_link);
+
 int __init classes_init(void)
 {
 	class_kset = kset_create_and_add("class", NULL, NULL);
@@ -426,8 +589,8 @@ int __init classes_init(void)
 	return 0;
 }
 
-EXPORT_SYMBOL_GPL(class_create_file);
-EXPORT_SYMBOL_GPL(class_remove_file);
+EXPORT_SYMBOL_GPL(class_create_file_ns);
+EXPORT_SYMBOL_GPL(class_remove_file_ns);
 EXPORT_SYMBOL_GPL(class_unregister);
 EXPORT_SYMBOL_GPL(class_destroy);