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>

diff --git a/drivers/base/base.h b/drivers/base/base.h
index 2c9ae43e221933607e81f32b26c40f7156447dc5..0ec372a67762696fbca984272a507da1fca2df86 100644 (file)
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -36,6 +36,33 @@ struct driver_private {
 };
 #define to_driver(obj) container_of(obj, struct driver_private, kobj)
 
+
+/**
+ * struct class_private - structure to hold the private to the driver core portions of the class structure.
+ *
+ * @subsys - the struct kset that defines this class.  This is the main kobject
+ * @children - list of class_devices associated with this class
+ * @devices - list of devices associated with this class
+ * @interfaces - list of class_interfaces associated with this class
+ * @class_dirs -
+ * @sem - semaphore to protect the children, devices, and interfaces lists.
+ * @class - pointer back to the struct class that this structure is associated
+ * with.
+ *
+ * This structure is the one that is the actual kobject allowing struct
+ * class to be statically allocated safely.  Nothing outside of the driver
+ * core should ever touch these fields.
+ */
+struct class_private {
+       struct kset subsys;
+       struct list_head devices;
+       struct list_head interfaces;
+       struct kset class_dirs;
+       struct semaphore sem;
+       struct class *class;
+};
+#define to_class(obj) container_of(obj, struct class_private, subsys.kobj)
+
 /* initialisation functions */
 extern int devices_init(void);
 extern int buses_init(void);

diff --git a/drivers/base/class.c b/drivers/base/class.c
index 3918d0e432d447565c6bfbfac09ab1d6db7e35c9..06f09c929a9189cbe3ea6c48e6c40f3d1855c788 100644 (file)
--- 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);
 }

diff --git a/drivers/base/core.c b/drivers/base/core.c
index 9f05de6f80b5fd7b8bd3f6bb66bc48eaee60ff8a..64c150b5a883ade1791905d8b9b6cfe3d5ceb4df 100644 (file)
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -551,7 +551,7 @@ static struct kobject *get_device_parent(struct device *dev,
 {
        /* class devices without a parent live in /sys/class/<classname>/ */
        if (dev->class && (!parent || parent->class != dev->class))
-               return &dev->class->subsys.kobj;
+               return &dev->class->p->subsys.kobj;
        /* all other devices keep their parent */
        else if (parent)
                return &parent->kobj;
@@ -597,13 +597,13 @@ static struct kobject *get_device_parent(struct device *dev,
                        parent_kobj = &parent->kobj;
 
                /* find our class-directory at the parent and reference it */
-               spin_lock(&dev->class->class_dirs.list_lock);
-               list_for_each_entry(k, &dev->class->class_dirs.list, entry)
+               spin_lock(&dev->class->p->class_dirs.list_lock);
+               list_for_each_entry(k, &dev->class->p->class_dirs.list, entry)
                        if (k->parent == parent_kobj) {
                                kobj = kobject_get(k);
                                break;
                        }
-               spin_unlock(&dev->class->class_dirs.list_lock);
+               spin_unlock(&dev->class->p->class_dirs.list_lock);
                if (kobj)
                        return kobj;
 
@@ -611,7 +611,7 @@ static struct kobject *get_device_parent(struct device *dev,
                k = kobject_create();
                if (!k)
                        return NULL;
-               k->kset = &dev->class->class_dirs;
+               k->kset = &dev->class->p->class_dirs;
                retval = kobject_add(k, parent_kobj, "%s", dev->class->name);
                if (retval < 0) {
                        kobject_put(k);
@@ -630,7 +630,7 @@ static void cleanup_glue_dir(struct device *dev, struct kobject *glue_dir)
 {
        /* see if we live in a "glue" directory */
        if (!glue_dir || !dev->class ||
-           glue_dir->kset != &dev->class->class_dirs)
+           glue_dir->kset != &dev->class->p->class_dirs)
                return;
 
        kobject_put(glue_dir);
@@ -657,17 +657,17 @@ static int device_add_class_symlinks(struct device *dev)
        if (!dev->class)
                return 0;
 
-       error = sysfs_create_link(&dev->kobj, &dev->class->subsys.kobj,
+       error = sysfs_create_link(&dev->kobj, &dev->class->p->subsys.kobj,
                                  "subsystem");
        if (error)
                goto out;
 
 #ifdef CONFIG_SYSFS_DEPRECATED
        /* stacked class devices need a symlink in the class directory */
-       if (dev->kobj.parent != &dev->class->subsys.kobj &&
+       if (dev->kobj.parent != &dev->class->p->subsys.kobj &&
            device_is_not_partition(dev)) {
-               error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
-                                         dev->bus_id);
+               error = sysfs_create_link(&dev->class->p->subsys.kobj,
+                                         &dev->kobj, dev->bus_id);
                if (error)
                        goto out_subsys;
        }
@@ -704,12 +704,12 @@ out_device:
        if (dev->parent && device_is_not_partition(dev))
                sysfs_remove_link(&dev->kobj, "device");
 out_busid:
-       if (dev->kobj.parent != &dev->class->subsys.kobj &&
+       if (dev->kobj.parent != &dev->class->p->subsys.kobj &&
            device_is_not_partition(dev))
-               sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+               sysfs_remove_link(&dev->class->p->subsys.kobj, dev->bus_id);
 #else
        /* link in the class directory pointing to the device */
-       error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
+       error = sysfs_create_link(&dev->class->p->subsys.kobj, &dev->kobj,
                                  dev->bus_id);
        if (error)
                goto out_subsys;
@@ -723,7 +723,7 @@ out_busid:
        return 0;
 
 out_busid:
-       sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+       sysfs_remove_link(&dev->class->p->subsys.kobj, dev->bus_id);
 #endif
 
 out_subsys:
@@ -749,14 +749,14 @@ static void device_remove_class_symlinks(struct device *dev)
                sysfs_remove_link(&dev->kobj, "device");
        }
 
-       if (dev->kobj.parent != &dev->class->subsys.kobj &&
+       if (dev->kobj.parent != &dev->class->p->subsys.kobj &&
            device_is_not_partition(dev))
-               sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+               sysfs_remove_link(&dev->class->p->subsys.kobj, dev->bus_id);
 #else
        if (dev->parent && device_is_not_partition(dev))
                sysfs_remove_link(&dev->kobj, "device");
 
-       sysfs_remove_link(&dev->class->subsys.kobj, dev->bus_id);
+       sysfs_remove_link(&dev->class->p->subsys.kobj, dev->bus_id);
 #endif
 
        sysfs_remove_link(&dev->kobj, "subsystem");
@@ -904,15 +904,16 @@ int device_add(struct device *dev)
                klist_add_tail(&dev->knode_parent, &parent->klist_children);
 
        if (dev->class) {
-               down(&dev->class->sem);
+               down(&dev->class->p->sem);
                /* tie the class to the device */
-               list_add_tail(&dev->node, &dev->class->devices);
+               list_add_tail(&dev->node, &dev->class->p->devices);
 
                /* notify any interfaces that the device is here */
-               list_for_each_entry(class_intf, &dev->class->interfaces, node)
+               list_for_each_entry(class_intf, &dev->class->p->interfaces,
+                                   node)
                        if (class_intf->add_dev)
                                class_intf->add_dev(dev, class_intf);
-               up(&dev->class->sem);
+               up(&dev->class->p->sem);
        }
  Done:
        put_device(dev);
@@ -1013,14 +1014,15 @@ void device_del(struct device *dev)
        if (dev->class) {
                device_remove_class_symlinks(dev);
 
-               down(&dev->class->sem);
+               down(&dev->class->p->sem);
                /* notify any interfaces that the device is now gone */
-               list_for_each_entry(class_intf, &dev->class->interfaces, node)
+               list_for_each_entry(class_intf, &dev->class->p->interfaces,
+                                   node)
                        if (class_intf->remove_dev)
                                class_intf->remove_dev(dev, class_intf);
                /* remove the device from the class list */
                list_del_init(&dev->node);
-               up(&dev->class->sem);
+               up(&dev->class->p->sem);
        }
        device_remove_file(dev, &uevent_attr);
        device_remove_attrs(dev);
@@ -1348,11 +1350,12 @@ int device_rename(struct device *dev, char *new_name)
        }
 #else
        if (dev->class) {
-               error = sysfs_create_link(&dev->class->subsys.kobj, &dev->kobj,
-                                         dev->bus_id);
+               error = sysfs_create_link(&dev->class->p->subsys.kobj,
+                                         &dev->kobj, dev->bus_id);
                if (error)
                        goto out;
-               sysfs_remove_link(&dev->class->subsys.kobj, old_device_name);
+               sysfs_remove_link(&dev->class->p->subsys.kobj,
+                                 old_device_name);
        }
 #endif
 

diff --git a/include/linux/device.h b/include/linux/device.h
index c1f72984875fb7b8f19b3c726abf999a3e5ccb70..b0556082179bf165128102f5bbbe1fc6e89a23df 100644 (file)
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -35,6 +35,7 @@ struct device;
 struct device_driver;
 struct driver_private;
 struct class;
+struct class_private;
 struct bus_type;
 struct bus_type_private;
 
@@ -186,11 +187,6 @@ struct class {
        const char              *name;
        struct module           *owner;
 
-       struct kset             subsys;
-       struct list_head        devices;
-       struct list_head        interfaces;
-       struct kset             class_dirs;
-       struct semaphore        sem; /* locks children, devices, interfaces */
        struct class_attribute          *class_attrs;
        struct device_attribute         *dev_attrs;
        struct kobject                  *dev_kobj;
@@ -204,6 +200,7 @@ struct class {
        int (*resume)(struct device *dev);
 
        struct pm_ops *pm;
+       struct class_private *p;
 };
 
 extern struct kobject *sysfs_dev_block_kobj;