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 2c9ae43..0ec372a 100644
--- a/drivers/base/base.h
+++ b/drivers/base/base.h
@@ -36,6 +36,33 @@
};
#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 3918d0e..06f09c9 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 @@
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 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 @@
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 @@
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 @@
#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 @@
{
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 @@
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 @@
if (error)
break;
}
- up(&class->sem);
+ up(&class->p->sem);
return error;
}
@@ -330,8 +339,8 @@
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 @@
} else
put_device(dev);
}
- up(&class->sem);
+ up(&class->p->sem);
return found ? dev : NULL;
}
@@ -362,13 +371,13 @@
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 @@
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 9f05de6..64c150b 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -551,7 +551,7 @@
{
/* 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 @@
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 @@
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 @@
{
/* 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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
}
#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 c1f7298..b055608 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -35,6 +35,7 @@
struct device_driver;
struct driver_private;
struct class;
+struct class_private;
struct bus_type;
struct bus_type_private;
@@ -186,11 +187,6 @@
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 @@
int (*resume)(struct device *dev);
struct pm_ops *pm;
+ struct class_private *p;
};
extern struct kobject *sysfs_dev_block_kobj;