driver core: move knode_bus into private structure
[safe/jmp/linux-2.6] / drivers / base / core.c
index c05b115..a90f56f 100644 (file)
@@ -53,7 +53,7 @@ static inline int device_is_not_partition(struct device *dev)
  * it is attached to.  If it is not attached to a bus either, an empty
  * string will be returned.
  */
-const char *dev_driver_string(struct device *dev)
+const char *dev_driver_string(const struct device *dev)
 {
        return dev->driver ? dev->driver->name :
                        (dev->bus ? dev->bus->name :
@@ -109,6 +109,7 @@ static struct sysfs_ops dev_sysfs_ops = {
 static void device_release(struct kobject *kobj)
 {
        struct device *dev = to_dev(kobj);
+       struct device_private *p = dev->p;
 
        if (dev->release)
                dev->release(dev);
@@ -116,12 +117,11 @@ static void device_release(struct kobject *kobj)
                dev->type->release(dev);
        else if (dev->class && dev->class->dev_release)
                dev->class->dev_release(dev);
-       else {
-               printk(KERN_ERR "Device '%s' does not have a release() "
+       else
+               WARN(1, KERN_ERR "Device '%s' does not have a release() "
                        "function, it is broken and must be fixed.\n",
-                       dev->bus_id);
-               WARN_ON(1);
-       }
+                       dev_name(dev));
+       kfree(p);
 }
 
 static struct kobj_type device_ktype = {
@@ -211,7 +211,7 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj,
                retval = dev->bus->uevent(dev, env);
                if (retval)
                        pr_debug("device: '%s': %s: bus uevent() returned %d\n",
-                                dev->bus_id, __func__, retval);
+                                dev_name(dev), __func__, retval);
        }
 
        /* have the class specific function add its stuff */
@@ -219,7 +219,7 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj,
                retval = dev->class->dev_uevent(dev, env);
                if (retval)
                        pr_debug("device: '%s': %s: class uevent() "
-                                "returned %d\n", dev->bus_id,
+                                "returned %d\n", dev_name(dev),
                                 __func__, retval);
        }
 
@@ -228,7 +228,7 @@ static int dev_uevent(struct kset *kset, struct kobject *kobj,
                retval = dev->type->uevent(dev, env);
                if (retval)
                        pr_debug("device: '%s': %s: dev_type uevent() "
-                                "returned %d\n", dev->bus_id,
+                                "returned %d\n", dev_name(dev),
                                 __func__, retval);
        }
 
@@ -509,14 +509,16 @@ EXPORT_SYMBOL_GPL(device_schedule_callback_owner);
 
 static void klist_children_get(struct klist_node *n)
 {
-       struct device *dev = container_of(n, struct device, knode_parent);
+       struct device_private *p = to_device_private_parent(n);
+       struct device *dev = p->device;
 
        get_device(dev);
 }
 
 static void klist_children_put(struct klist_node *n)
 {
-       struct device *dev = container_of(n, struct device, knode_parent);
+       struct device_private *p = to_device_private_parent(n);
+       struct device *dev = p->device;
 
        put_device(dev);
 }
@@ -525,24 +527,27 @@ static void klist_children_put(struct klist_node *n)
  * device_initialize - init device structure.
  * @dev: device.
  *
- * This prepares the device for use by other layers,
- * including adding it to the device hierarchy.
+ * This prepares the device for use by other layers by initializing
+ * its fields.
  * It is the first half of device_register(), if called by
- * that, though it can also be called separately, so one
- * may use @dev's fields (e.g. the refcount).
+ * that function, though it can also be called separately, so one
+ * may use @dev's fields. In particular, get_device()/put_device()
+ * may be used for reference counting of @dev after calling this
+ * function.
+ *
+ * NOTE: Use put_device() to give up your reference instead of freeing
+ * @dev directly once you have called this function.
  */
 void device_initialize(struct device *dev)
 {
        dev->kobj.kset = devices_kset;
        kobject_init(&dev->kobj, &device_ktype);
-       klist_init(&dev->klist_children, klist_children_get,
-                  klist_children_put);
        INIT_LIST_HEAD(&dev->dma_pools);
-       INIT_LIST_HEAD(&dev->node);
        init_MUTEX(&dev->sem);
        spin_lock_init(&dev->devres_lock);
        INIT_LIST_HEAD(&dev->devres_head);
        device_init_wakeup(dev, 0);
+       device_pm_init(dev);
        set_dev_node(dev, -1);
 }
 
@@ -669,7 +674,7 @@ static int device_add_class_symlinks(struct device *dev)
        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
            device_is_not_partition(dev)) {
                error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
-                                         &dev->kobj, dev->bus_id);
+                                         &dev->kobj, dev_name(dev));
                if (error)
                        goto out_subsys;
        }
@@ -709,11 +714,11 @@ out_busid:
        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
            device_is_not_partition(dev))
                sysfs_remove_link(&dev->class->p->class_subsys.kobj,
-                                 dev->bus_id);
+                                 dev_name(dev));
 #else
        /* link in the class directory pointing to the device */
        error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
-                                 &dev->kobj, dev->bus_id);
+                                 &dev->kobj, dev_name(dev));
        if (error)
                goto out_subsys;
 
@@ -726,7 +731,7 @@ out_busid:
        return 0;
 
 out_busid:
-       sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev->bus_id);
+       sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev_name(dev));
 #endif
 
 out_subsys:
@@ -755,12 +760,12 @@ static void device_remove_class_symlinks(struct device *dev)
        if (dev->kobj.parent != &dev->class->p->class_subsys.kobj &&
            device_is_not_partition(dev))
                sysfs_remove_link(&dev->class->p->class_subsys.kobj,
-                                 dev->bus_id);
+                                 dev_name(dev));
 #else
        if (dev->parent && device_is_not_partition(dev))
                sysfs_remove_link(&dev->kobj, "device");
 
-       sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev->bus_id);
+       sysfs_remove_link(&dev->class->p->class_subsys.kobj, dev_name(dev));
 #endif
 
        sysfs_remove_link(&dev->kobj, "subsystem");
@@ -774,11 +779,12 @@ static void device_remove_class_symlinks(struct device *dev)
 int dev_set_name(struct device *dev, const char *fmt, ...)
 {
        va_list vargs;
+       int err;
 
        va_start(vargs, fmt);
-       vsnprintf(dev->bus_id, sizeof(dev->bus_id), fmt, vargs);
+       err = kobject_set_name_vargs(&dev->kobj, fmt, vargs);
        va_end(vargs);
-       return 0;
+       return err;
 }
 EXPORT_SYMBOL_GPL(dev_set_name);
 
@@ -837,23 +843,47 @@ static void device_remove_sys_dev_entry(struct device *dev)
  * This is part 2 of device_register(), though may be called
  * separately _iff_ device_initialize() has been called separately.
  *
- * This adds it to the kobject hierarchy via kobject_add(), adds it
+ * This adds @dev to the kobject hierarchy via kobject_add(), adds it
  * to the global and sibling lists for the device, then
  * adds it to the other relevant subsystems of the driver model.
+ *
+ * NOTE: _Never_ directly free @dev after calling this function, even
+ * if it returned an error! Always use put_device() to give up your
+ * reference instead.
  */
 int device_add(struct device *dev)
 {
        struct device *parent = NULL;
        struct class_interface *class_intf;
-       int error;
+       int error = -EINVAL;
 
        dev = get_device(dev);
-       if (!dev || !strlen(dev->bus_id)) {
-               error = -EINVAL;
-               goto Done;
+       if (!dev)
+               goto done;
+
+       dev->p = kzalloc(sizeof(*dev->p), GFP_KERNEL);
+       if (!dev->p) {
+               error = -ENOMEM;
+               goto done;
        }
+       dev->p->device = dev;
+       klist_init(&dev->p->klist_children, klist_children_get,
+                  klist_children_put);
 
-       pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
+       /*
+        * for statically allocated devices, which should all be converted
+        * some day, we need to initialize the name. We prevent reading back
+        * the name, and force the use of dev_name()
+        */
+       if (dev->init_name) {
+               dev_set_name(dev, dev->init_name);
+               dev->init_name = NULL;
+       }
+
+       if (!dev_name(dev))
+               goto done;
+
+       pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
 
        parent = get_device(dev->parent);
        setup_parent(dev, parent);
@@ -863,7 +893,7 @@ int device_add(struct device *dev)
                set_dev_node(dev, dev_to_node(parent));
 
        /* first, register with generic layer. */
-       error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev->bus_id);
+       error = kobject_add(&dev->kobj, dev->kobj.parent, "%s", dev_name(dev));
        if (error)
                goto Error;
 
@@ -871,11 +901,6 @@ int device_add(struct device *dev)
        if (platform_notify)
                platform_notify(dev);
 
-       /* notify clients of device entry (new way) */
-       if (dev->bus)
-               blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
-                                            BUS_NOTIFY_ADD_DEVICE, dev);
-
        error = device_create_file(dev, &uevent_attr);
        if (error)
                goto attrError;
@@ -899,18 +924,29 @@ int device_add(struct device *dev)
        error = bus_add_device(dev);
        if (error)
                goto BusError;
-       error = device_pm_add(dev);
+       error = dpm_sysfs_add(dev);
        if (error)
-               goto PMError;
+               goto DPMError;
+       device_pm_add(dev);
+
+       /* Notify clients of device addition.  This call must come
+        * after dpm_sysf_add() and before kobject_uevent().
+        */
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
+                                            BUS_NOTIFY_ADD_DEVICE, dev);
+
        kobject_uevent(&dev->kobj, KOBJ_ADD);
        bus_attach_device(dev);
        if (parent)
-               klist_add_tail(&dev->knode_parent, &parent->klist_children);
+               klist_add_tail(&dev->p->knode_parent,
+                              &parent->p->klist_children);
 
        if (dev->class) {
                mutex_lock(&dev->class->p->class_mutex);
                /* tie the class to the device */
-               list_add_tail(&dev->node, &dev->class->p->class_devices);
+               klist_add_tail(&dev->knode_class,
+                              &dev->class->p->class_devices);
 
                /* notify any interfaces that the device is here */
                list_for_each_entry(class_intf,
@@ -919,15 +955,12 @@ int device_add(struct device *dev)
                                class_intf->add_dev(dev, class_intf);
                mutex_unlock(&dev->class->p->class_mutex);
        }
- Done:
+done:
        put_device(dev);
        return error;
- PMError:
DPMError:
        bus_remove_device(dev);
  BusError:
-       if (dev->bus)
-               blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
-                                            BUS_NOTIFY_DEL_DEVICE, dev);
        device_remove_attrs(dev);
  AttrsError:
        device_remove_class_symlinks(dev);
@@ -946,7 +979,7 @@ int device_add(struct device *dev)
        cleanup_device_parent(dev);
        if (parent)
                put_device(parent);
-       goto Done;
+       goto done;
 }
 
 /**
@@ -959,6 +992,10 @@ int device_add(struct device *dev)
  * I.e. you should only call the two helpers separately if
  * have a clearly defined need to use and refcount the device
  * before it is added to the hierarchy.
+ *
+ * NOTE: _Never_ directly free @dev after calling this function, even
+ * if it returned an error! Always use put_device() to give up the
+ * reference initialized in this function instead.
  */
 int device_register(struct device *dev)
 {
@@ -1008,9 +1045,16 @@ void device_del(struct device *dev)
        struct device *parent = dev->parent;
        struct class_interface *class_intf;
 
+       /* Notify clients of device removal.  This call must come
+        * before dpm_sysfs_remove().
+        */
+       if (dev->bus)
+               blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
+                                            BUS_NOTIFY_DEL_DEVICE, dev);
        device_pm_remove(dev);
+       dpm_sysfs_remove(dev);
        if (parent)
-               klist_del(&dev->knode_parent);
+               klist_del(&dev->p->knode_parent);
        if (MAJOR(dev->devt)) {
                device_remove_sys_dev_entry(dev);
                device_remove_file(dev, &devt_attr);
@@ -1025,7 +1069,7 @@ void device_del(struct device *dev)
                        if (class_intf->remove_dev)
                                class_intf->remove_dev(dev, class_intf);
                /* remove the device from the class list */
-               list_del_init(&dev->node);
+               klist_del(&dev->knode_class);
                mutex_unlock(&dev->class->p->class_mutex);
        }
        device_remove_file(dev, &uevent_attr);
@@ -1044,9 +1088,6 @@ void device_del(struct device *dev)
         */
        if (platform_notify_remove)
                platform_notify_remove(dev);
-       if (dev->bus)
-               blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
-                                            BUS_NOTIFY_DEL_DEVICE, dev);
        kobject_uevent(&dev->kobj, KOBJ_REMOVE);
        cleanup_device_parent(dev);
        kobject_del(&dev->kobj);
@@ -1066,7 +1107,7 @@ void device_del(struct device *dev)
  */
 void device_unregister(struct device *dev)
 {
-       pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
+       pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
        device_del(dev);
        put_device(dev);
 }
@@ -1074,7 +1115,14 @@ void device_unregister(struct device *dev)
 static struct device *next_device(struct klist_iter *i)
 {
        struct klist_node *n = klist_next(i);
-       return n ? container_of(n, struct device, knode_parent) : NULL;
+       struct device *dev = NULL;
+       struct device_private *p;
+
+       if (n) {
+               p = to_device_private_parent(n);
+               dev = p->device;
+       }
+       return dev;
 }
 
 /**
@@ -1096,7 +1144,7 @@ int device_for_each_child(struct device *parent, void *data,
        struct device *child;
        int error = 0;
 
-       klist_iter_init(&parent->klist_children, &i);
+       klist_iter_init(&parent->p->klist_children, &i);
        while ((child = next_device(&i)) && !error)
                error = fn(child, data);
        klist_iter_exit(&i);
@@ -1127,7 +1175,7 @@ struct device *device_find_child(struct device *parent, void *data,
        if (!parent)
                return NULL;
 
-       klist_iter_init(&parent->klist_children, &i);
+       klist_iter_init(&parent->p->klist_children, &i);
        while ((child = next_device(&i)))
                if (match(child, data) && get_device(child))
                        break;
@@ -1176,10 +1224,101 @@ EXPORT_SYMBOL_GPL(put_device);
 EXPORT_SYMBOL_GPL(device_create_file);
 EXPORT_SYMBOL_GPL(device_remove_file);
 
+struct root_device
+{
+       struct device dev;
+       struct module *owner;
+};
+
+#define to_root_device(dev) container_of(dev, struct root_device, dev)
+
+static void root_device_release(struct device *dev)
+{
+       kfree(to_root_device(dev));
+}
+
+/**
+ * __root_device_register - allocate and register a root device
+ * @name: root device name
+ * @owner: owner module of the root device, usually THIS_MODULE
+ *
+ * This function allocates a root device and registers it
+ * using device_register(). In order to free the returned
+ * device, use root_device_unregister().
+ *
+ * Root devices are dummy devices which allow other devices
+ * to be grouped under /sys/devices. Use this function to
+ * allocate a root device and then use it as the parent of
+ * any device which should appear under /sys/devices/{name}
+ *
+ * The /sys/devices/{name} directory will also contain a
+ * 'module' symlink which points to the @owner directory
+ * in sysfs.
+ *
+ * Note: You probably want to use root_device_register().
+ */
+struct device *__root_device_register(const char *name, struct module *owner)
+{
+       struct root_device *root;
+       int err = -ENOMEM;
+
+       root = kzalloc(sizeof(struct root_device), GFP_KERNEL);
+       if (!root)
+               return ERR_PTR(err);
+
+       err = dev_set_name(&root->dev, name);
+       if (err) {
+               kfree(root);
+               return ERR_PTR(err);
+       }
+
+       root->dev.release = root_device_release;
+
+       err = device_register(&root->dev);
+       if (err) {
+               put_device(&root->dev);
+               return ERR_PTR(err);
+       }
+
+#ifdef CONFIG_MODULE   /* gotta find a "cleaner" way to do this */
+       if (owner) {
+               struct module_kobject *mk = &owner->mkobj;
+
+               err = sysfs_create_link(&root->dev.kobj, &mk->kobj, "module");
+               if (err) {
+                       device_unregister(&root->dev);
+                       return ERR_PTR(err);
+               }
+               root->owner = owner;
+       }
+#endif
+
+       return &root->dev;
+}
+EXPORT_SYMBOL_GPL(__root_device_register);
+
+/**
+ * root_device_unregister - unregister and free a root device
+ * @dev: device going away
+ *
+ * This function unregisters and cleans up a device that was created by
+ * root_device_register().
+ */
+void root_device_unregister(struct device *dev)
+{
+       struct root_device *root = to_root_device(dev);
+
+       if (root->owner)
+               sysfs_remove_link(&root->dev.kobj, "module");
+
+       device_unregister(dev);
+}
+EXPORT_SYMBOL_GPL(root_device_unregister);
+
 
 static void device_create_release(struct device *dev)
 {
-       pr_debug("device: '%s': %s\n", dev->bus_id, __func__);
+       pr_debug("device: '%s': %s\n", dev_name(dev), __func__);
        kfree(dev);
 }
 
@@ -1228,7 +1367,10 @@ struct device *device_create_vargs(struct class *class, struct device *parent,
        dev->release = device_create_release;
        dev_set_drvdata(dev, drvdata);
 
-       vsnprintf(dev->bus_id, BUS_ID_SIZE, fmt, args);
+       retval = kobject_set_name_vargs(&dev->kobj, fmt, args);
+       if (retval)
+               goto error;
+
        retval = device_register(dev);
        if (retval)
                goto error;
@@ -1236,7 +1378,7 @@ struct device *device_create_vargs(struct class *class, struct device *parent,
        return dev;
 
 error:
-       kfree(dev);
+       put_device(dev);
        return ERR_PTR(retval);
 }
 EXPORT_SYMBOL_GPL(device_create_vargs);
@@ -1307,6 +1449,11 @@ EXPORT_SYMBOL_GPL(device_destroy);
  * device_rename - renames a device
  * @dev: the pointer to the struct device to be renamed
  * @new_name: the new name of the device
+ *
+ * It is the responsibility of the caller to provide mutual
+ * exclusion between two different calls of device_rename
+ * on the same device to ensure that new_name is valid and
+ * won't conflict with other devices.
  */
 int device_rename(struct device *dev, char *new_name)
 {
@@ -1319,7 +1466,7 @@ int device_rename(struct device *dev, char *new_name)
        if (!dev)
                return -EINVAL;
 
-       pr_debug("device: '%s': %s: renaming to '%s'\n", dev->bus_id,
+       pr_debug("device: '%s': %s: renaming to '%s'\n", dev_name(dev),
                 __func__, new_name);
 
 #ifdef CONFIG_SYSFS_DEPRECATED
@@ -1327,26 +1474,23 @@ int device_rename(struct device *dev, char *new_name)
                old_class_name = make_class_name(dev->class->name, &dev->kobj);
 #endif
 
-       old_device_name = kmalloc(BUS_ID_SIZE, GFP_KERNEL);
+       old_device_name = kstrdup(dev_name(dev), GFP_KERNEL);
        if (!old_device_name) {
                error = -ENOMEM;
                goto out;
        }
-       strlcpy(old_device_name, dev->bus_id, BUS_ID_SIZE);
-       strlcpy(dev->bus_id, new_name, BUS_ID_SIZE);
 
        error = kobject_rename(&dev->kobj, new_name);
-       if (error) {
-               strlcpy(dev->bus_id, old_device_name, BUS_ID_SIZE);
+       if (error)
                goto out;
-       }
 
 #ifdef CONFIG_SYSFS_DEPRECATED
        if (old_class_name) {
                new_class_name = make_class_name(dev->class->name, &dev->kobj);
                if (new_class_name) {
-                       error = sysfs_create_link(&dev->parent->kobj,
-                                                 &dev->kobj, new_class_name);
+                       error = sysfs_create_link_nowarn(&dev->parent->kobj,
+                                                        &dev->kobj,
+                                                        new_class_name);
                        if (error)
                                goto out;
                        sysfs_remove_link(&dev->parent->kobj, old_class_name);
@@ -1354,8 +1498,8 @@ int device_rename(struct device *dev, char *new_name)
        }
 #else
        if (dev->class) {
-               error = sysfs_create_link(&dev->class->p->class_subsys.kobj,
-                                         &dev->kobj, dev->bus_id);
+               error = sysfs_create_link_nowarn(&dev->class->p->class_subsys.kobj,
+                                                &dev->kobj, dev_name(dev));
                if (error)
                        goto out;
                sysfs_remove_link(&dev->class->p->class_subsys.kobj,
@@ -1433,8 +1577,8 @@ int device_move(struct device *dev, struct device *new_parent)
        new_parent = get_device(new_parent);
        new_parent_kobj = get_device_parent(dev, new_parent);
 
-       pr_debug("device: '%s': %s: moving to '%s'\n", dev->bus_id,
-                __func__, new_parent ? new_parent->bus_id : "<NULL>");
+       pr_debug("device: '%s': %s: moving to '%s'\n", dev_name(dev),
+                __func__, new_parent ? dev_name(new_parent) : "<NULL>");
        error = kobject_move(&dev->kobj, new_parent_kobj);
        if (error) {
                cleanup_glue_dir(dev, new_parent_kobj);
@@ -1444,9 +1588,10 @@ int device_move(struct device *dev, struct device *new_parent)
        old_parent = dev->parent;
        dev->parent = new_parent;
        if (old_parent)
-               klist_remove(&dev->knode_parent);
+               klist_remove(&dev->p->knode_parent);
        if (new_parent) {
-               klist_add_tail(&dev->knode_parent, &new_parent->klist_children);
+               klist_add_tail(&dev->p->knode_parent,
+                              &new_parent->p->klist_children);
                set_dev_node(dev, dev_to_node(new_parent));
        }
 
@@ -1458,11 +1603,11 @@ int device_move(struct device *dev, struct device *new_parent)
                device_move_class_links(dev, new_parent, old_parent);
                if (!kobject_move(&dev->kobj, &old_parent->kobj)) {
                        if (new_parent)
-                               klist_remove(&dev->knode_parent);
+                               klist_remove(&dev->p->knode_parent);
                        dev->parent = old_parent;
                        if (old_parent) {
-                               klist_add_tail(&dev->knode_parent,
-                                              &old_parent->klist_children);
+                               klist_add_tail(&dev->p->knode_parent,
+                                              &old_parent->p->klist_children);
                                set_dev_node(dev, dev_to_node(old_parent));
                        }
                }