#include <linux/err.h>
#include <linux/slab.h>
#include <linux/genhd.h>
+#include <linux/mutex.h>
#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;
}
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);
.release = class_release,
};
-/* Hotplug events for classes go to the class_obj subsys */
+/* Hotplug events for classes go to the class class_subsys */
static struct kset *class_kset;
{
int error;
if (cls)
- error = sysfs_create_file(&cls->subsys.kobj, &attr->attr);
+ error = sysfs_create_file(&cls->p->class_subsys.kobj,
+ &attr->attr);
else
error = -EINVAL;
return error;
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->class_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->class_subsys);
+ return cls;
}
static void class_put(struct class *cls)
{
if (cls)
- kset_put(&cls->subsys);
+ kset_put(&cls->p->class_subsys);
}
static int add_class_attrs(struct class *cls)
}
}
-int class_register(struct class *cls)
+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;
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;
+ klist_init(&cp->class_devices, klist_class_dev_get, klist_class_dev_put);
+ 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);
+ if (error) {
+ kfree(cp);
return error;
+ }
/* set the default /sys/dev directory for devices of this class */
if (!cls->dev_kobj)
#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->class_subsys.kobj.kset = class_kset;
#else
- cls->subsys.kobj.kset = class_kset;
+ cp->class_subsys.kobj.kset = class_kset;
#endif
- cls->subsys.kobj.ktype = &class_ktype;
+ cp->class_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->class_subsys);
+ if (error) {
+ kfree(cp);
+ return error;
}
+ error = add_class_attrs(class_get(cls));
+ class_put(cls);
return error;
}
+EXPORT_SYMBOL_GPL(__class_register);
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->class_subsys);
}
static void class_create_release(struct class *cls)
* class_create - create a struct class structure
* @owner: pointer to the module that is to "own" this struct class
* @name: pointer to a string for the name of this class.
+ * @key: the lock_class_key for this class; used by mutex lock debugging
*
* This is used to create a struct class pointer that can then be used
* in calls to device_create().
* Note, the pointer created here is to be destroyed when finished by
* making a call to class_destroy().
*/
-struct class *class_create(struct module *owner, const char *name)
+struct class *__class_create(struct module *owner, const char *name,
+ struct lock_class_key *key)
{
struct class *cls;
int retval;
cls->owner = owner;
cls->class_release = class_create_release;
- retval = class_register(cls);
+ retval = __class_register(cls, key);
if (retval)
goto error;
kfree(cls);
return ERR_PTR(retval);
}
+EXPORT_SYMBOL_GPL(__class_create);
/**
* class_destroy - destroys a struct class structure
#endif
/**
+ * 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)
+{
+ struct klist_node *start_knode = NULL;
+
+ if (start)
+ start_knode = &start->knode_class;
+ klist_iter_init_node(&class->p->class_devices, &iter->ki, start_knode);
+ iter->type = type;
+}
+EXPORT_SYMBOL_GPL(class_dev_iter_init);
+
+/**
+ * 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;
+
+ 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;
+ }
+}
+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
* @class: the class we're iterating
+ * @start: the device to start with in the list, if any.
* @data: data for the callback
* @fn: function to be called for each device
*
* Iterate over @class's list of devices, and call @fn for each,
- * passing it @data.
+ * passing it @data. If @start is set, the list iteration will start
+ * there, otherwise if it is NULL, the iteration starts at the
+ * beginning of the list.
*
* 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->sem 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, void *data,
- int (*fn)(struct device *, void *))
+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;
if (!class)
return -EINVAL;
- down(&class->sem);
- list_for_each_entry(dev, &class->devices, node) {
- dev = get_device(dev);
- if (dev) {
- error = fn(dev, data);
- put_device(dev);
- } else
- error = -ENODEV;
+ if (!class->p) {
+ WARN(1, "%s called for class '%s' before it was initialized",
+ __func__, class->name);
+ return -EINVAL;
+ }
+
+ class_dev_iter_init(&iter, class, start, NULL);
+ while ((dev = class_dev_iter_next(&iter))) {
+ error = fn(dev, data);
if (error)
break;
}
- up(&class->sem);
+ class_dev_iter_exit(&iter);
return error;
}
/**
* class_find_device - device iterator for locating a particular device
* @class: the class we're iterating
+ * @start: Device to begin with
* @data: data for the match function
* @match: function to check device
*
*
* Note, you will need to drop the reference with put_device() after use.
*
- * We hold class->sem 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, void *data,
- int (*match)(struct device *, void *))
+struct device *class_find_device(struct class *class, struct device *start,
+ void *data,
+ int (*match)(struct device *, void *))
{
+ struct class_dev_iter iter;
struct device *dev;
- int found = 0;
if (!class)
return NULL;
+ if (!class->p) {
+ WARN(1, "%s called for class '%s' before it was initialized",
+ __func__, class->name);
+ return NULL;
+ }
- down(&class->sem);
- list_for_each_entry(dev, &class->devices, node) {
- dev = get_device(dev);
- if (dev) {
- if (match(dev, data)) {
- found = 1;
- break;
- } else
- put_device(dev);
- } else
+ class_dev_iter_init(&iter, class, start, NULL);
+ while ((dev = class_dev_iter_next(&iter))) {
+ if (match(dev, data)) {
+ get_device(dev);
break;
+ }
}
- up(&class->sem);
+ 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)
if (!parent)
return -EINVAL;
- down(&parent->sem);
- list_add_tail(&class_intf->node, &parent->interfaces);
+ mutex_lock(&parent->p->class_mutex);
+ list_add_tail(&class_intf->node, &parent->p->class_interfaces);
if (class_intf->add_dev) {
- list_for_each_entry(dev, &parent->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);
}
- up(&parent->sem);
+ mutex_unlock(&parent->p->class_mutex);
return 0;
}
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;
- down(&parent->sem);
+ mutex_lock(&parent->p->class_mutex);
list_del_init(&class_intf->node);
if (class_intf->remove_dev) {
- list_for_each_entry(dev, &parent->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);
}
- up(&parent->sem);
+ mutex_unlock(&parent->p->class_mutex);
class_put(parent);
}
+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);
EXPORT_SYMBOL_GPL(class_create_file);
EXPORT_SYMBOL_GPL(class_remove_file);
-EXPORT_SYMBOL_GPL(class_register);
EXPORT_SYMBOL_GPL(class_unregister);
-EXPORT_SYMBOL_GPL(class_create);
EXPORT_SYMBOL_GPL(class_destroy);
EXPORT_SYMBOL_GPL(class_interface_register);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff