* kobject.c - library routines for handling generic kernel objects
*
* Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org>
+ * Copyright (c) 2006-2007 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (c) 2006-2007 Novell Inc.
*
* This file is released under the GPLv2.
*
return error;
}
-static int create_dir(struct kobject *kobj, struct sysfs_dirent *shadow_parent)
+static int create_dir(struct kobject * kobj)
{
int error = 0;
if (kobject_name(kobj)) {
- error = sysfs_create_dir(kobj, shadow_parent);
+ error = sysfs_create_dir(kobj);
if (!error) {
if ((error = populate_dir(kobj)))
sysfs_remove_dir(kobj);
return;
kref_init(&kobj->kref);
INIT_LIST_HEAD(&kobj->entry);
- init_waitqueue_head(&kobj->poll);
kobj->kset = kset_get(kobj->kset);
}
}
/**
- * kobject_shadow_add - add an object to the hierarchy.
+ * kobject_add - add an object to the hierarchy.
* @kobj: object.
- * @shadow_parent: sysfs directory to add to.
*/
-int kobject_shadow_add(struct kobject *kobj, struct sysfs_dirent *shadow_parent)
+int kobject_add(struct kobject * kobj)
{
int error = 0;
struct kobject * parent;
if (!(kobj = kobject_get(kobj)))
return -ENOENT;
if (!kobj->k_name)
- kobj->k_name = kobj->name;
+ kobject_set_name(kobj, "NO_NAME");
if (!*kobj->k_name) {
pr_debug("kobject attempted to be registered with no name!\n");
WARN_ON(1);
pr_debug("kobject %s: registering. parent: %s, set: %s\n",
kobject_name(kobj), parent ? kobject_name(parent) : "<NULL>",
- kobj->kset ? kobj->kset->kobj.name : "<NULL>" );
+ kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" );
if (kobj->kset) {
spin_lock(&kobj->kset->list_lock);
- if (!parent)
+ if (!parent) {
parent = kobject_get(&kobj->kset->kobj);
+ /*
+ * If the kset is our parent, get a second
+ * reference, we drop both the kset and the
+ * parent ref on cleanup
+ */
+ kobject_get(parent);
+ }
list_add_tail(&kobj->entry,&kobj->kset->list);
spin_unlock(&kobj->kset->list_lock);
kobj->parent = parent;
}
- error = create_dir(kobj, shadow_parent);
+ error = create_dir(kobj);
if (error) {
/* unlink does the kobject_put() for us */
unlink(kobj);
return error;
}
-/**
- * kobject_add - add an object to the hierarchy.
- * @kobj: object.
- */
-int kobject_add(struct kobject * kobj)
-{
- return kobject_shadow_add(kobj, NULL);
-}
-
-
/**
* kobject_register - initialize and add an object.
* @kobj: object in question.
return error;
}
+/**
+ * kobject_set_name_vargs - Set the name of an kobject
+ * @kobj: struct kobject to set the name of
+ * @fmt: format string used to build the name
+ * @vargs: vargs to format the string.
+ */
+static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
+ va_list vargs)
+{
+ va_list aq;
+ char *name;
+
+ va_copy(aq, vargs);
+ name = kvasprintf(GFP_KERNEL, fmt, vargs);
+ va_end(aq);
+
+ if (!name)
+ return -ENOMEM;
+
+ /* Free the old name, if necessary. */
+ kfree(kobj->k_name);
+
+ /* Now, set the new name */
+ kobj->k_name = name;
+
+ return 0;
+}
/**
- * kobject_set_name - Set the name of an object
- * @kobj: object.
- * @fmt: format string used to build the name
+ * kobject_set_name - Set the name of a kobject
+ * @kobj: struct kobject to set the name of
+ * @fmt: format string used to build the name
*
- * If strlen(name) >= KOBJ_NAME_LEN, then use a dynamically allocated
- * string that @kobj->k_name points to. Otherwise, use the static
- * @kobj->name array.
+ * This sets the name of the kobject. If you have already added the
+ * kobject to the system, you must call kobject_rename() in order to
+ * change the name of the kobject.
*/
-int kobject_set_name(struct kobject * kobj, const char * fmt, ...)
+int kobject_set_name(struct kobject *kobj, const char *fmt, ...)
{
- int error = 0;
- int limit = KOBJ_NAME_LEN;
- int need;
va_list args;
- char * name;
+ int retval;
- /*
- * First, try the static array
- */
- va_start(args,fmt);
- need = vsnprintf(kobj->name,limit,fmt,args);
+ va_start(args, fmt);
+ retval = kobject_set_name_vargs(kobj, fmt, args);
va_end(args);
- if (need < limit)
- name = kobj->name;
- else {
- /*
- * Need more space? Allocate it and try again
- */
- limit = need + 1;
- name = kmalloc(limit,GFP_KERNEL);
- if (!name) {
- error = -ENOMEM;
- goto Done;
- }
- va_start(args,fmt);
- need = vsnprintf(name,limit,fmt,args);
- va_end(args);
-
- /* Still? Give up. */
- if (need >= limit) {
- kfree(name);
- error = -EFAULT;
- goto Done;
- }
+
+ return retval;
+}
+EXPORT_SYMBOL(kobject_set_name);
+
+/**
+ * kobject_init_ng - initialize a kobject structure
+ * @kobj: pointer to the kobject to initialize
+ * @ktype: pointer to the ktype for this kobject.
+ *
+ * This function will properly initialize a kobject such that it can then
+ * be passed to the kobject_add() call.
+ *
+ * After this function is called, the kobject MUST be cleaned up by a call
+ * to kobject_put(), not by a call to kfree directly to ensure that all of
+ * the memory is cleaned up properly.
+ */
+void kobject_init_ng(struct kobject *kobj, struct kobj_type *ktype)
+{
+ char *err_str;
+
+ if (!kobj) {
+ err_str = "invalid kobject pointer!";
+ goto error;
+ }
+ if (!ktype) {
+ err_str = "must have a ktype to be initialized properly!\n";
+ goto error;
+ }
+ if (atomic_read(&kobj->kref.refcount)) {
+ /* do not error out as sometimes we can recover */
+ printk(KERN_ERR "kobject: reference count is already set, "
+ "something is seriously wrong.\n");
+ dump_stack();
}
- /* Free the old name, if necessary. */
- if (kobj->k_name && kobj->k_name != kobj->name)
- kfree(kobj->k_name);
+ kref_init(&kobj->kref);
+ INIT_LIST_HEAD(&kobj->entry);
+ kobj->ktype = ktype;
+ return;
- /* Now, set the new name */
- kobj->k_name = name;
- Done:
- return error;
+error:
+ printk(KERN_ERR "kobject: %s\n", err_str);
+ dump_stack();
}
+EXPORT_SYMBOL(kobject_init_ng);
-EXPORT_SYMBOL(kobject_set_name);
+static int kobject_add_varg(struct kobject *kobj, struct kobject *parent,
+ const char *fmt, va_list vargs)
+{
+ va_list aq;
+ int retval;
+
+ va_copy(aq, vargs);
+ retval = kobject_set_name_vargs(kobj, fmt, aq);
+ va_end(aq);
+ if (retval) {
+ printk(KERN_ERR "kobject: can not set name properly!\n");
+ return retval;
+ }
+ kobj->parent = parent;
+ return kobject_add(kobj);
+}
+
+/**
+ * kobject_add_ng - the main kobject add function
+ * @kobj: the kobject to add
+ * @parent: pointer to the parent of the kobject.
+ * @fmt: format to name the kobject with.
+ *
+ * The kobject name is set and added to the kobject hierarchy in this
+ * function.
+ *
+ * If @parent is set, then the parent of the @kobj will be set to it.
+ * If @parent is NULL, then the parent of the @kobj will be set to the
+ * kobject associted with the kset assigned to this kobject. If no kset
+ * is assigned to the kobject, then the kobject will be located in the
+ * root of the sysfs tree.
+ *
+ * If this function returns an error, kobject_put() must be called to
+ * properly clean up the memory associated with the object.
+ *
+ * If the function is successful, the only way to properly clean up the
+ * memory is with a call to kobject_del(), in which case, a call to
+ * kobject_put() is not necessary (kobject_del() does the final
+ * kobject_put() to call the release function in the ktype's release
+ * pointer.)
+ *
+ * Under no instance should the kobject that is passed to this function
+ * be directly freed with a call to kfree(), that can leak memory.
+ *
+ * Note, no uevent will be created with this call, the caller should set
+ * up all of the necessary sysfs files for the object and then call
+ * kobject_uevent() with the UEVENT_ADD parameter to ensure that
+ * userspace is properly notified of this kobject's creation.
+ */
+int kobject_add_ng(struct kobject *kobj, struct kobject *parent,
+ const char *fmt, ...)
+{
+ va_list args;
+ int retval;
+
+ if (!kobj)
+ return -EINVAL;
+ va_start(args, fmt);
+ retval = kobject_add_varg(kobj, parent, fmt, args);
+ va_end(args);
+
+ return retval;
+}
+EXPORT_SYMBOL(kobject_add_ng);
+
+/**
+ * kobject_init_and_add - initialize a kobject structure and add it to the kobject hierarchy
+ * @kobj: pointer to the kobject to initialize
+ * @ktype: pointer to the ktype for this kobject.
+ * @parent: pointer to the parent of this kobject.
+ * @fmt: the name of the kobject.
+ *
+ * This function combines the call to kobject_init_ng() and
+ * kobject_add_ng(). The same type of error handling after a call to
+ * kobject_add_ng() and kobject lifetime rules are the same here.
+ */
+int kobject_init_and_add(struct kobject *kobj, struct kobj_type *ktype,
+ struct kobject *parent, const char *fmt, ...)
+{
+ va_list args;
+ int retval;
+
+ kobject_init_ng(kobj, ktype);
+
+ va_start(args, fmt);
+ retval = kobject_add_varg(kobj, parent, fmt, args);
+ va_end(args);
+
+ return retval;
+}
+EXPORT_SYMBOL_GPL(kobject_init_and_add);
/**
* kobject_rename - change the name of an object
if (!kobj->parent)
return -EINVAL;
+ /* see if this name is already in use */
+ if (kobj->kset) {
+ struct kobject *temp_kobj;
+ temp_kobj = kset_find_obj(kobj->kset, new_name);
+ if (temp_kobj) {
+ printk(KERN_WARNING "kobject '%s' cannot be renamed "
+ "to '%s' as '%s' is already in existence.\n",
+ kobject_name(kobj), new_name, new_name);
+ kobject_put(temp_kobj);
+ return -EINVAL;
+ }
+ }
+
devpath = kobject_get_path(kobj, GFP_KERNEL);
if (!devpath) {
error = -ENOMEM;
sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
envp[0] = devpath_string;
envp[1] = NULL;
- /* Note : if we want to send the new name alone, not the full path,
- * we could probably use kobject_name(kobj); */
- error = sysfs_rename_dir(kobj, kobj->parent->sd, new_name);
+ error = sysfs_rename_dir(kobj, new_name);
/* This function is mostly/only used for network interface.
* Some hotplug package track interfaces by their name and
return error;
}
-/**
- * kobject_rename - change the name of an object
- * @kobj: object in question.
- * @new_parent: object's new parent
- * @new_name: object's new name
- */
-
-int kobject_shadow_rename(struct kobject *kobj,
- struct sysfs_dirent *new_parent, const char *new_name)
-{
- int error = 0;
-
- kobj = kobject_get(kobj);
- if (!kobj)
- return -EINVAL;
- error = sysfs_rename_dir(kobj, new_parent, new_name);
- kobject_put(kobj);
-
- return error;
-}
-
/**
* kobject_move - move object to another parent
* @kobj: object in question.
return kobj;
}
-/**
- * kobject_cleanup - free kobject resources.
- * @kobj: object.
+/*
+ * kobject_cleanup - free kobject resources.
+ * @kobj: object to cleanup
*/
-
-void kobject_cleanup(struct kobject * kobj)
+static void kobject_cleanup(struct kobject *kobj)
{
struct kobj_type * t = get_ktype(kobj);
struct kset * s = kobj->kset;
struct kobject * parent = kobj->parent;
+ const char *name = kobj->k_name;
pr_debug("kobject %s: cleaning up\n",kobject_name(kobj));
- if (kobj->k_name != kobj->name)
- kfree(kobj->k_name);
- kobj->k_name = NULL;
- if (t && t->release)
+ if (t && t->release) {
t->release(kobj);
+ /* If we have a release function, we can guess that this was
+ * not a statically allocated kobject, so we should be safe to
+ * free the name */
+ kfree(name);
+ }
if (s)
kset_put(s);
kobject_put(parent);
kref_put(&kobj->kref, kobject_release);
}
-
-static void dir_release(struct kobject *kobj)
+static void dynamic_kobj_release(struct kobject *kobj)
{
+ pr_debug("%s: freeing %s\n", __FUNCTION__, kobject_name(kobj));
kfree(kobj);
}
-static struct kobj_type dir_ktype = {
- .release = dir_release,
- .sysfs_ops = NULL,
- .default_attrs = NULL,
+static struct kobj_type dynamic_kobj_ktype = {
+ .release = dynamic_kobj_release,
+ .sysfs_ops = &kobj_sysfs_ops,
};
/**
- * kobject_kset_add_dir - add sub directory of object.
- * @kset: kset the directory is belongs to.
- * @parent: object in which a directory is created.
- * @name: directory name.
+ * kobject_create - create a struct kobject dynamically
+ *
+ * This function creates a kobject structure dynamically and sets it up
+ * to be a "dynamic" kobject with a default release function set up.
*
- * Add a plain directory object as child of given object.
+ * If the kobject was not able to be created, NULL will be returned.
+ * The kobject structure returned from here must be cleaned up with a
+ * call to kobject_put() and not kfree(), as kobject_init_ng() has
+ * already been called on this structure.
*/
-struct kobject *kobject_kset_add_dir(struct kset *kset,
- struct kobject *parent, const char *name)
+struct kobject *kobject_create(void)
{
- struct kobject *k;
- int ret;
+ struct kobject *kobj;
- if (!parent)
- return NULL;
-
- k = kzalloc(sizeof(*k), GFP_KERNEL);
- if (!k)
+ kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
+ if (!kobj)
return NULL;
- k->kset = kset;
- k->parent = parent;
- k->ktype = &dir_ktype;
- kobject_set_name(k, name);
- ret = kobject_register(k);
- if (ret < 0) {
- printk(KERN_WARNING "%s: kobject_register error: %d\n",
- __func__, ret);
- kobject_del(k);
- return NULL;
- }
-
- return k;
+ kobject_init_ng(kobj, &dynamic_kobj_ktype);
+ return kobj;
}
/**
- * kobject_add_dir - add sub directory of object.
- * @parent: object in which a directory is created.
- * @name: directory name.
+ * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs
+ *
+ * @name: the name for the kset
+ * @parent: the parent kobject of this kobject, if any.
*
- * Add a plain directory object as child of given object.
+ * This function creates a kset structure dynamically and registers it
+ * with sysfs. When you are finished with this structure, call
+ * kobject_unregister() and the structure will be dynamically freed when
+ * it is no longer being used.
+ *
+ * If the kobject was not able to be created, NULL will be returned.
*/
-struct kobject *kobject_add_dir(struct kobject *parent, const char *name)
+struct kobject *kobject_create_and_add(const char *name, struct kobject *parent)
{
- return kobject_kset_add_dir(NULL, parent, name);
+ struct kobject *kobj;
+ int retval;
+
+ kobj = kobject_create();
+ if (!kobj)
+ return NULL;
+
+ retval = kobject_add_ng(kobj, parent, "%s", name);
+ if (retval) {
+ printk(KERN_WARNING "%s: kobject_add error: %d\n",
+ __FUNCTION__, retval);
+ kobject_put(kobj);
+ kobj = NULL;
+ }
+ return kobj;
}
+EXPORT_SYMBOL_GPL(kobject_create_and_add);
/**
* kset_init - initialize a kset for use
spin_lock_init(&k->list_lock);
}
+/* default kobject attribute operations */
+static ssize_t kobj_attr_show(struct kobject *kobj, struct attribute *attr,
+ char *buf)
+{
+ struct kobj_attribute *kattr;
+ ssize_t ret = -EIO;
+
+ kattr = container_of(attr, struct kobj_attribute, attr);
+ if (kattr->show)
+ ret = kattr->show(kobj, kattr, buf);
+ return ret;
+}
+
+static ssize_t kobj_attr_store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct kobj_attribute *kattr;
+ ssize_t ret = -EIO;
+
+ kattr = container_of(attr, struct kobj_attribute, attr);
+ if (kattr->store)
+ ret = kattr->store(kobj, kattr, buf, count);
+ return ret;
+}
+
+struct sysfs_ops kobj_sysfs_ops = {
+ .show = kobj_attr_show,
+ .store = kobj_attr_store,
+};
/**
* kset_add - add a kset object to the hierarchy.
return ret;
}
-void subsystem_init(struct kset *s)
-{
- kset_init(s);
-}
-
int subsystem_register(struct kset *s)
{
return kset_register(s);
kset_unregister(s);
}
+static void kset_release(struct kobject *kobj)
+{
+ struct kset *kset = container_of(kobj, struct kset, kobj);
+ pr_debug("kset %s: now freed\n", kobject_name(kobj));
+ kfree(kset);
+}
+
+static struct kobj_type kset_ktype = {
+ .sysfs_ops = &kobj_sysfs_ops,
+ .release = kset_release,
+};
+
/**
- * subsystem_create_file - export sysfs attribute file.
- * @s: subsystem.
- * @a: subsystem attribute descriptor.
+ * kset_create - create a struct kset dynamically
+ *
+ * @name: the name for the kset
+ * @uevent_ops: a struct kset_uevent_ops for the kset
+ * @parent_kobj: the parent kobject of this kset, if any.
+ *
+ * This function creates a kset structure dynamically. This structure can
+ * then be registered with the system and show up in sysfs with a call to
+ * kset_register(). When you are finished with this structure, if
+ * kset_register() has been called, call kset_unregister() and the
+ * structure will be dynamically freed when it is no longer being used.
+ *
+ * If the kset was not able to be created, NULL will be returned.
*/
-
-int subsys_create_file(struct kset *s, struct subsys_attribute *a)
+static struct kset *kset_create(const char *name,
+ struct kset_uevent_ops *uevent_ops,
+ struct kobject *parent_kobj)
{
- int error = 0;
+ struct kset *kset;
- if (!s || !a)
- return -EINVAL;
+ kset = kzalloc(sizeof(*kset), GFP_KERNEL);
+ if (!kset)
+ return NULL;
+ kobject_set_name(&kset->kobj, name);
+ kset->uevent_ops = uevent_ops;
+ kset->kobj.parent = parent_kobj;
+
+ /*
+ * The kobject of this kset will have a type of kset_ktype and belong to
+ * no kset itself. That way we can properly free it when it is
+ * finished being used.
+ */
+ kset->kobj.ktype = &kset_ktype;
+ kset->kobj.kset = NULL;
+
+ return kset;
+}
- if (subsys_get(s)) {
- error = sysfs_create_file(&s->kobj, &a->attr);
- subsys_put(s);
+/**
+ * kset_create_and_add - create a struct kset dynamically and add it to sysfs
+ *
+ * @name: the name for the kset
+ * @uevent_ops: a struct kset_uevent_ops for the kset
+ * @parent_kobj: the parent kobject of this kset, if any.
+ *
+ * This function creates a kset structure dynamically and registers it
+ * with sysfs. When you are finished with this structure, call
+ * kset_unregister() and the structure will be dynamically freed when it
+ * is no longer being used.
+ *
+ * If the kset was not able to be created, NULL will be returned.
+ */
+struct kset *kset_create_and_add(const char *name,
+ struct kset_uevent_ops *uevent_ops,
+ struct kobject *parent_kobj)
+{
+ struct kset *kset;
+ int error;
+
+ kset = kset_create(name, uevent_ops, parent_kobj);
+ if (!kset)
+ return NULL;
+ error = kset_register(kset);
+ if (error) {
+ kfree(kset);
+ return NULL;
}
- return error;
+ return kset;
}
+EXPORT_SYMBOL_GPL(kset_create_and_add);
EXPORT_SYMBOL(kobject_init);
EXPORT_SYMBOL(kobject_register);
EXPORT_SYMBOL(subsystem_register);
EXPORT_SYMBOL(subsystem_unregister);
-EXPORT_SYMBOL(subsys_create_file);