class: move driver core specific parts to a private structure

This moves the portions of struct class that are dynamic (kobject and
lock and lists) out of the main structure and into a dynamic, private,
structure.


Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 48 insertions, 39 deletions

diff --git a/drivers/base/class.c b/drivers/base/class.c
index 3918d0e432d4..06f09c929a91 100644
--- a/drivers/base/class.c
+++ b/drivers/base/class.c
@@ -21,17 +21,16 @@
 #include "base.h"
 
 #define to_class_attr(_attr) container_of(_attr, struct class_attribute, attr)
-#define to_class(obj) container_of(obj, struct class, subsys.kobj)
 
 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 *dc = to_class(kobj);
+        struct class_private *cp = to_class(kobj);
         ssize_t ret = -EIO;
 
         if (class_attr->show)
-                ret = class_attr->show(dc, buf);
+                ret = class_attr->show(cp->class, buf);
         return ret;
 }
 
@@ -39,17 +38,18 @@ 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 *dc = to_class(kobj);
+        struct class_private *cp = to_class(kobj);
         ssize_t ret = -EIO;
 
         if (class_attr->store)
-                ret = class_attr->store(dc, buf, count);
+                ret = class_attr->store(cp->class, buf, count);
         return ret;
 }
 
 static void class_release(struct kobject *kobj)
 {
-        struct class *class = to_class(kobj);
+        struct class_private *cp = to_class(kobj);
+        struct class *class = cp->class;
 
         pr_debug("class '%s': release.\n", class->name);
 
@@ -78,7 +78,7 @@ int class_create_file(struct class *cls, const struct class_attribute *attr)
 {
         int error;
         if (cls)
-                error = sysfs_create_file(&cls->subsys.kobj, &attr->attr);
+                error = sysfs_create_file(&cls->p->subsys.kobj, &attr->attr);
         else
                 error = -EINVAL;
         return error;
@@ -87,21 +87,20 @@ int class_create_file(struct class *cls, const struct class_attribute *attr)
 void class_remove_file(struct class *cls, const struct class_attribute *attr)
 {
         if (cls)
-                sysfs_remove_file(&cls->subsys.kobj, &attr->attr);
+                sysfs_remove_file(&cls->p->subsys.kobj, &attr->attr);
 }
 
 static struct class *class_get(struct class *cls)
 {
         if (cls)
-                return container_of(kset_get(&cls->subsys),
-                                    struct class, subsys);
-        return NULL;
+                kset_get(&cls->p->subsys);
+        return cls;
 }
 
 static void class_put(struct class *cls)
 {
         if (cls)
-                kset_put(&cls->subsys);
+                kset_put(&cls->p->subsys);
 }
 
 static int add_class_attrs(struct class *cls)
@@ -136,17 +135,23 @@ static void remove_class_attrs(struct class *cls)
 
 int class_register(struct class *cls)
 {
+        struct class_private *cp;
         int error;
 
         pr_debug("device class '%s': registering\n", cls->name);
 
-        INIT_LIST_HEAD(&cls->devices);
-        INIT_LIST_HEAD(&cls->interfaces);
-        kset_init(&cls->class_dirs);
-        init_MUTEX(&cls->sem);
-        error = kobject_set_name(&cls->subsys.kobj, "%s", cls->name);
-        if (error)
+        cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+        if (!cp)
+                return -ENOMEM;
+        INIT_LIST_HEAD(&cp->devices);
+        INIT_LIST_HEAD(&cp->interfaces);
+        kset_init(&cp->class_dirs);
+        init_MUTEX(&cp->sem);
+        error = kobject_set_name(&cp->subsys.kobj, "%s", cls->name);
+        if (error) {
+                kfree(cp);
                 return error;
+        }
 
         /* set the default /sys/dev directory for devices of this class */
         if (!cls->dev_kobj)
@@ -155,17 +160,21 @@ int class_register(struct class *cls)
 #if defined(CONFIG_SYSFS_DEPRECATED) && defined(CONFIG_BLOCK)
         /* let the block class directory show up in the root of sysfs */
         if (cls != &block_class)
-                cls->subsys.kobj.kset = class_kset;
+                cp->subsys.kobj.kset = class_kset;
 #else
-        cls->subsys.kobj.kset = class_kset;
+        cp->subsys.kobj.kset = class_kset;
 #endif
-        cls->subsys.kobj.ktype = &class_ktype;
+        cp->subsys.kobj.ktype = &class_ktype;
+        cp->class = cls;
+        cls->p = cp;
 
-        error = kset_register(&cls->subsys);
-        if (!error) {
-                error = add_class_attrs(class_get(cls));
-                class_put(cls);
+        error = kset_register(&cp->subsys);
+        if (error) {
+                kfree(cp);
+                return error;
         }
+        error = add_class_attrs(class_get(cls));
+        class_put(cls);
         return error;
 }
 
@@ -173,7 +182,7 @@ void class_unregister(struct class *cls)
 {
         pr_debug("device class '%s': unregistering\n", cls->name);
         remove_class_attrs(cls);
-        kset_unregister(&cls->subsys);
+        kset_unregister(&cls->p->subsys);
 }
 
 static void class_create_release(struct class *cls)
@@ -280,8 +289,8 @@ int class_for_each_device(struct class *class, struct device *start,
 
         if (!class)
                 return -EINVAL;
-        down(&class->sem);
-        list_for_each_entry(dev, &class->devices, node) {
+        down(&class->p->sem);
+        list_for_each_entry(dev, &class->p->devices, node) {
                 if (start) {
                         if (start == dev)
                                 start = NULL;
@@ -293,7 +302,7 @@ int class_for_each_device(struct class *class, struct device *start,
                 if (error)
                         break;
         }
-        up(&class->sem);
+        up(&class->p->sem);
 
         return error;
 }
@@ -330,8 +339,8 @@ struct device *class_find_device(struct class *class, struct device *start,
         if (!class)
                 return NULL;
 
-        down(&class->sem);
-        list_for_each_entry(dev, &class->devices, node) {
+        down(&class->p->sem);
+        list_for_each_entry(dev, &class->p->devices, node) {
                 if (start) {
                         if (start == dev)
                                 start = NULL;
@@ -344,7 +353,7 @@ struct device *class_find_device(struct class *class, struct device *start,
                 } else
                         put_device(dev);
         }
-        up(&class->sem);
+        up(&class->p->sem);
 
         return found ? dev : NULL;
 }
@@ -362,13 +371,13 @@ int class_interface_register(struct class_interface *class_intf)
         if (!parent)
                 return -EINVAL;
 
-        down(&parent->sem);
-        list_add_tail(&class_intf->node, &parent->interfaces);
+        down(&parent->p->sem);
+        list_add_tail(&class_intf->node, &parent->p->interfaces);
         if (class_intf->add_dev) {
-                list_for_each_entry(dev, &parent->devices, node)
+                list_for_each_entry(dev, &parent->p->devices, node)
                         class_intf->add_dev(dev, class_intf);
         }
-        up(&parent->sem);
+        up(&parent->p->sem);
 
         return 0;
 }
@@ -381,13 +390,13 @@ void class_interface_unregister(struct class_interface *class_intf)
         if (!parent)
                 return;
 
-        down(&parent->sem);
+        down(&parent->p->sem);
         list_del_init(&class_intf->node);
         if (class_intf->remove_dev) {
-                list_for_each_entry(dev, &parent->devices, node)
+                list_for_each_entry(dev, &parent->p->devices, node)
                         class_intf->remove_dev(dev, class_intf);
         }
-        up(&parent->sem);
+        up(&parent->p->sem);
 
         class_put(parent);
 }