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- // SPDX-License-Identifier: GPL-2.0
- /*
- * kobject.c - library routines for handling generic kernel objects
- *
- * Copyright (c) 2002-2003 Patrick Mochel <[email protected]>
- * Copyright (c) 2006-2007 Greg Kroah-Hartman <[email protected]>
- * Copyright (c) 2006-2007 Novell Inc.
- *
- * Please see the file Documentation/core-api/kobject.rst for critical information
- * about using the kobject interface.
- */
- #include <linux/kobject.h>
- #include <linux/string.h>
- #include <linux/export.h>
- #include <linux/stat.h>
- #include <linux/slab.h>
- #include <linux/random.h>
- /**
- * kobject_namespace() - Return @kobj's namespace tag.
- * @kobj: kobject in question
- *
- * Returns namespace tag of @kobj if its parent has namespace ops enabled
- * and thus @kobj should have a namespace tag associated with it. Returns
- * %NULL otherwise.
- */
- const void *kobject_namespace(struct kobject *kobj)
- {
- const struct kobj_ns_type_operations *ns_ops = kobj_ns_ops(kobj);
- if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE)
- return NULL;
- return kobj->ktype->namespace(kobj);
- }
- /**
- * kobject_get_ownership() - Get sysfs ownership data for @kobj.
- * @kobj: kobject in question
- * @uid: kernel user ID for sysfs objects
- * @gid: kernel group ID for sysfs objects
- *
- * Returns initial uid/gid pair that should be used when creating sysfs
- * representation of given kobject. Normally used to adjust ownership of
- * objects in a container.
- */
- void kobject_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid)
- {
- *uid = GLOBAL_ROOT_UID;
- *gid = GLOBAL_ROOT_GID;
- if (kobj->ktype->get_ownership)
- kobj->ktype->get_ownership(kobj, uid, gid);
- }
- static int create_dir(struct kobject *kobj)
- {
- const struct kobj_type *ktype = get_ktype(kobj);
- const struct kobj_ns_type_operations *ops;
- int error;
- error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj));
- if (error)
- return error;
- if (ktype) {
- error = sysfs_create_groups(kobj, ktype->default_groups);
- if (error) {
- sysfs_remove_dir(kobj);
- return error;
- }
- }
- /*
- * @kobj->sd may be deleted by an ancestor going away. Hold an
- * extra reference so that it stays until @kobj is gone.
- */
- sysfs_get(kobj->sd);
- /*
- * If @kobj has ns_ops, its children need to be filtered based on
- * their namespace tags. Enable namespace support on @kobj->sd.
- */
- ops = kobj_child_ns_ops(kobj);
- if (ops) {
- BUG_ON(ops->type <= KOBJ_NS_TYPE_NONE);
- BUG_ON(ops->type >= KOBJ_NS_TYPES);
- BUG_ON(!kobj_ns_type_registered(ops->type));
- sysfs_enable_ns(kobj->sd);
- }
- return 0;
- }
- static int get_kobj_path_length(const struct kobject *kobj)
- {
- int length = 1;
- const struct kobject *parent = kobj;
- /* walk up the ancestors until we hit the one pointing to the
- * root.
- * Add 1 to strlen for leading '/' of each level.
- */
- do {
- if (kobject_name(parent) == NULL)
- return 0;
- length += strlen(kobject_name(parent)) + 1;
- parent = parent->parent;
- } while (parent);
- return length;
- }
- static int fill_kobj_path(const struct kobject *kobj, char *path, int length)
- {
- const struct kobject *parent;
- --length;
- for (parent = kobj; parent; parent = parent->parent) {
- int cur = strlen(kobject_name(parent));
- /* back up enough to print this name with '/' */
- length -= cur;
- if (length <= 0)
- return -EINVAL;
- memcpy(path + length, kobject_name(parent), cur);
- *(path + --length) = '/';
- }
- pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj),
- kobj, __func__, path);
- return 0;
- }
- /**
- * kobject_get_path() - Allocate memory and fill in the path for @kobj.
- * @kobj: kobject in question, with which to build the path
- * @gfp_mask: the allocation type used to allocate the path
- *
- * Return: The newly allocated memory, caller must free with kfree().
- */
- char *kobject_get_path(const struct kobject *kobj, gfp_t gfp_mask)
- {
- char *path;
- int len;
- retry:
- len = get_kobj_path_length(kobj);
- if (len == 0)
- return NULL;
- path = kzalloc(len, gfp_mask);
- if (!path)
- return NULL;
- if (fill_kobj_path(kobj, path, len)) {
- kfree(path);
- goto retry;
- }
- return path;
- }
- EXPORT_SYMBOL_GPL(kobject_get_path);
- /* add the kobject to its kset's list */
- static void kobj_kset_join(struct kobject *kobj)
- {
- if (!kobj->kset)
- return;
- kset_get(kobj->kset);
- spin_lock(&kobj->kset->list_lock);
- list_add_tail(&kobj->entry, &kobj->kset->list);
- spin_unlock(&kobj->kset->list_lock);
- }
- /* remove the kobject from its kset's list */
- static void kobj_kset_leave(struct kobject *kobj)
- {
- if (!kobj->kset)
- return;
- spin_lock(&kobj->kset->list_lock);
- list_del_init(&kobj->entry);
- spin_unlock(&kobj->kset->list_lock);
- kset_put(kobj->kset);
- }
- static void kobject_init_internal(struct kobject *kobj)
- {
- if (!kobj)
- return;
- kref_init(&kobj->kref);
- INIT_LIST_HEAD(&kobj->entry);
- kobj->state_in_sysfs = 0;
- kobj->state_add_uevent_sent = 0;
- kobj->state_remove_uevent_sent = 0;
- kobj->state_initialized = 1;
- }
- static int kobject_add_internal(struct kobject *kobj)
- {
- int error = 0;
- struct kobject *parent;
- if (!kobj)
- return -ENOENT;
- if (!kobj->name || !kobj->name[0]) {
- WARN(1,
- "kobject: (%p): attempted to be registered with empty name!\n",
- kobj);
- return -EINVAL;
- }
- parent = kobject_get(kobj->parent);
- /* join kset if set, use it as parent if we do not already have one */
- if (kobj->kset) {
- if (!parent)
- parent = kobject_get(&kobj->kset->kobj);
- kobj_kset_join(kobj);
- kobj->parent = parent;
- }
- pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n",
- kobject_name(kobj), kobj, __func__,
- parent ? kobject_name(parent) : "<NULL>",
- kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>");
- error = create_dir(kobj);
- if (error) {
- kobj_kset_leave(kobj);
- kobject_put(parent);
- kobj->parent = NULL;
- /* be noisy on error issues */
- if (error == -EEXIST)
- pr_err("%s failed for %s with -EEXIST, don't try to register things with the same name in the same directory.\n",
- __func__, kobject_name(kobj));
- else
- pr_err("%s failed for %s (error: %d parent: %s)\n",
- __func__, kobject_name(kobj), error,
- parent ? kobject_name(parent) : "'none'");
- } else
- kobj->state_in_sysfs = 1;
- return error;
- }
- /**
- * kobject_set_name_vargs() - Set the name of a kobject.
- * @kobj: struct kobject to set the name of
- * @fmt: format string used to build the name
- * @vargs: vargs to format the string.
- */
- int kobject_set_name_vargs(struct kobject *kobj, const char *fmt,
- va_list vargs)
- {
- const char *s;
- if (kobj->name && !fmt)
- return 0;
- s = kvasprintf_const(GFP_KERNEL, fmt, vargs);
- if (!s)
- return -ENOMEM;
- /*
- * ewww... some of these buggers have '/' in the name ... If
- * that's the case, we need to make sure we have an actual
- * allocated copy to modify, since kvasprintf_const may have
- * returned something from .rodata.
- */
- if (strchr(s, '/')) {
- char *t;
- t = kstrdup(s, GFP_KERNEL);
- kfree_const(s);
- if (!t)
- return -ENOMEM;
- strreplace(t, '/', '!');
- s = t;
- }
- kfree_const(kobj->name);
- kobj->name = s;
- return 0;
- }
- /**
- * 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
- *
- * 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, ...)
- {
- va_list vargs;
- int retval;
- va_start(vargs, fmt);
- retval = kobject_set_name_vargs(kobj, fmt, vargs);
- va_end(vargs);
- return retval;
- }
- EXPORT_SYMBOL(kobject_set_name);
- /**
- * kobject_init() - 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(struct kobject *kobj, const 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 (kobj->state_initialized) {
- /* do not error out as sometimes we can recover */
- pr_err("kobject (%p): tried to init an initialized object, something is seriously wrong.\n",
- kobj);
- dump_stack();
- }
- kobject_init_internal(kobj);
- kobj->ktype = ktype;
- return;
- error:
- pr_err("kobject (%p): %s\n", kobj, err_str);
- dump_stack();
- }
- EXPORT_SYMBOL(kobject_init);
- static __printf(3, 0) int kobject_add_varg(struct kobject *kobj,
- struct kobject *parent,
- const char *fmt, va_list vargs)
- {
- int retval;
- retval = kobject_set_name_vargs(kobj, fmt, vargs);
- if (retval) {
- pr_err("kobject: can not set name properly!\n");
- return retval;
- }
- kobj->parent = parent;
- return kobject_add_internal(kobj);
- }
- /**
- * kobject_add() - 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 associated 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.
- *
- * Note, no "add" 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.
- *
- * Return: If this function returns an error, kobject_put() must be
- * called to properly clean up the memory associated with the
- * object. Under no instance should the kobject that is passed
- * to this function be directly freed with a call to kfree(),
- * that can leak memory.
- *
- * If this function returns success, kobject_put() must also be called
- * in order to properly clean up the memory associated with the object.
- *
- * In short, once this function is called, kobject_put() MUST be called
- * when the use of the object is finished in order to properly free
- * everything.
- */
- int kobject_add(struct kobject *kobj, struct kobject *parent,
- const char *fmt, ...)
- {
- va_list args;
- int retval;
- if (!kobj)
- return -EINVAL;
- if (!kobj->state_initialized) {
- pr_err("kobject '%s' (%p): tried to add an uninitialized object, something is seriously wrong.\n",
- kobject_name(kobj), kobj);
- dump_stack();
- return -EINVAL;
- }
- va_start(args, fmt);
- retval = kobject_add_varg(kobj, parent, fmt, args);
- va_end(args);
- return retval;
- }
- EXPORT_SYMBOL(kobject_add);
- /**
- * 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() and kobject_add().
- *
- * If this function returns an error, kobject_put() must be called to
- * properly clean up the memory associated with the object. This is the
- * same type of error handling after a call to kobject_add() and kobject
- * lifetime rules are the same here.
- */
- int kobject_init_and_add(struct kobject *kobj, const struct kobj_type *ktype,
- struct kobject *parent, const char *fmt, ...)
- {
- va_list args;
- int retval;
- kobject_init(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.
- * @kobj: object in question.
- * @new_name: object's new name
- *
- * It is the responsibility of the caller to provide mutual
- * exclusion between two different calls of kobject_rename
- * on the same kobject and to ensure that new_name is valid and
- * won't conflict with other kobjects.
- */
- int kobject_rename(struct kobject *kobj, const char *new_name)
- {
- int error = 0;
- const char *devpath = NULL;
- const char *dup_name = NULL, *name;
- char *devpath_string = NULL;
- char *envp[2];
- kobj = kobject_get(kobj);
- if (!kobj)
- return -EINVAL;
- if (!kobj->parent) {
- kobject_put(kobj);
- return -EINVAL;
- }
- devpath = kobject_get_path(kobj, GFP_KERNEL);
- if (!devpath) {
- error = -ENOMEM;
- goto out;
- }
- devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
- if (!devpath_string) {
- error = -ENOMEM;
- goto out;
- }
- sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
- envp[0] = devpath_string;
- envp[1] = NULL;
- name = dup_name = kstrdup_const(new_name, GFP_KERNEL);
- if (!name) {
- error = -ENOMEM;
- goto out;
- }
- error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj));
- if (error)
- goto out;
- /* Install the new kobject name */
- dup_name = kobj->name;
- kobj->name = name;
- /* This function is mostly/only used for network interface.
- * Some hotplug package track interfaces by their name and
- * therefore want to know when the name is changed by the user. */
- kobject_uevent_env(kobj, KOBJ_MOVE, envp);
- out:
- kfree_const(dup_name);
- kfree(devpath_string);
- kfree(devpath);
- kobject_put(kobj);
- return error;
- }
- EXPORT_SYMBOL_GPL(kobject_rename);
- /**
- * kobject_move() - Move object to another parent.
- * @kobj: object in question.
- * @new_parent: object's new parent (can be NULL)
- */
- int kobject_move(struct kobject *kobj, struct kobject *new_parent)
- {
- int error;
- struct kobject *old_parent;
- const char *devpath = NULL;
- char *devpath_string = NULL;
- char *envp[2];
- kobj = kobject_get(kobj);
- if (!kobj)
- return -EINVAL;
- new_parent = kobject_get(new_parent);
- if (!new_parent) {
- if (kobj->kset)
- new_parent = kobject_get(&kobj->kset->kobj);
- }
- /* old object path */
- devpath = kobject_get_path(kobj, GFP_KERNEL);
- if (!devpath) {
- error = -ENOMEM;
- goto out;
- }
- devpath_string = kmalloc(strlen(devpath) + 15, GFP_KERNEL);
- if (!devpath_string) {
- error = -ENOMEM;
- goto out;
- }
- sprintf(devpath_string, "DEVPATH_OLD=%s", devpath);
- envp[0] = devpath_string;
- envp[1] = NULL;
- error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj));
- if (error)
- goto out;
- old_parent = kobj->parent;
- kobj->parent = new_parent;
- new_parent = NULL;
- kobject_put(old_parent);
- kobject_uevent_env(kobj, KOBJ_MOVE, envp);
- out:
- kobject_put(new_parent);
- kobject_put(kobj);
- kfree(devpath_string);
- kfree(devpath);
- return error;
- }
- EXPORT_SYMBOL_GPL(kobject_move);
- static void __kobject_del(struct kobject *kobj)
- {
- struct kernfs_node *sd;
- const struct kobj_type *ktype;
- sd = kobj->sd;
- ktype = get_ktype(kobj);
- if (ktype)
- sysfs_remove_groups(kobj, ktype->default_groups);
- /* send "remove" if the caller did not do it but sent "add" */
- if (kobj->state_add_uevent_sent && !kobj->state_remove_uevent_sent) {
- pr_debug("kobject: '%s' (%p): auto cleanup 'remove' event\n",
- kobject_name(kobj), kobj);
- kobject_uevent(kobj, KOBJ_REMOVE);
- }
- sysfs_remove_dir(kobj);
- sysfs_put(sd);
- kobj->state_in_sysfs = 0;
- kobj_kset_leave(kobj);
- kobj->parent = NULL;
- }
- /**
- * kobject_del() - Unlink kobject from hierarchy.
- * @kobj: object.
- *
- * This is the function that should be called to delete an object
- * successfully added via kobject_add().
- */
- void kobject_del(struct kobject *kobj)
- {
- struct kobject *parent;
- if (!kobj)
- return;
- parent = kobj->parent;
- __kobject_del(kobj);
- kobject_put(parent);
- }
- EXPORT_SYMBOL(kobject_del);
- /**
- * kobject_get() - Increment refcount for object.
- * @kobj: object.
- */
- struct kobject *kobject_get(struct kobject *kobj)
- {
- if (kobj) {
- if (!kobj->state_initialized)
- WARN(1, KERN_WARNING
- "kobject: '%s' (%p): is not initialized, yet kobject_get() is being called.\n",
- kobject_name(kobj), kobj);
- kref_get(&kobj->kref);
- }
- return kobj;
- }
- EXPORT_SYMBOL(kobject_get);
- struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj)
- {
- if (!kobj)
- return NULL;
- if (!kref_get_unless_zero(&kobj->kref))
- kobj = NULL;
- return kobj;
- }
- EXPORT_SYMBOL(kobject_get_unless_zero);
- /*
- * kobject_cleanup - free kobject resources.
- * @kobj: object to cleanup
- */
- static void kobject_cleanup(struct kobject *kobj)
- {
- struct kobject *parent = kobj->parent;
- const struct kobj_type *t = get_ktype(kobj);
- const char *name = kobj->name;
- pr_debug("kobject: '%s' (%p): %s, parent %p\n",
- kobject_name(kobj), kobj, __func__, kobj->parent);
- if (t && !t->release)
- pr_debug("kobject: '%s' (%p): does not have a release() function, it is broken and must be fixed. See Documentation/core-api/kobject.rst.\n",
- kobject_name(kobj), kobj);
- /* remove from sysfs if the caller did not do it */
- if (kobj->state_in_sysfs) {
- pr_debug("kobject: '%s' (%p): auto cleanup kobject_del\n",
- kobject_name(kobj), kobj);
- __kobject_del(kobj);
- } else {
- /* avoid dropping the parent reference unnecessarily */
- parent = NULL;
- }
- if (t && t->release) {
- pr_debug("kobject: '%s' (%p): calling ktype release\n",
- kobject_name(kobj), kobj);
- t->release(kobj);
- }
- /* free name if we allocated it */
- if (name) {
- pr_debug("kobject: '%s': free name\n", name);
- kfree_const(name);
- }
- kobject_put(parent);
- }
- #ifdef CONFIG_DEBUG_KOBJECT_RELEASE
- static void kobject_delayed_cleanup(struct work_struct *work)
- {
- kobject_cleanup(container_of(to_delayed_work(work),
- struct kobject, release));
- }
- #endif
- static void kobject_release(struct kref *kref)
- {
- struct kobject *kobj = container_of(kref, struct kobject, kref);
- #ifdef CONFIG_DEBUG_KOBJECT_RELEASE
- unsigned long delay = HZ + HZ * prandom_u32_max(4);
- pr_info("kobject: '%s' (%p): %s, parent %p (delayed %ld)\n",
- kobject_name(kobj), kobj, __func__, kobj->parent, delay);
- INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup);
- schedule_delayed_work(&kobj->release, delay);
- #else
- kobject_cleanup(kobj);
- #endif
- }
- /**
- * kobject_put() - Decrement refcount for object.
- * @kobj: object.
- *
- * Decrement the refcount, and if 0, call kobject_cleanup().
- */
- void kobject_put(struct kobject *kobj)
- {
- if (kobj) {
- if (!kobj->state_initialized)
- WARN(1, KERN_WARNING
- "kobject: '%s' (%p): is not initialized, yet kobject_put() is being called.\n",
- kobject_name(kobj), kobj);
- kref_put(&kobj->kref, kobject_release);
- }
- }
- EXPORT_SYMBOL(kobject_put);
- static void dynamic_kobj_release(struct kobject *kobj)
- {
- pr_debug("kobject: (%p): %s\n", kobj, __func__);
- kfree(kobj);
- }
- static struct kobj_type dynamic_kobj_ktype = {
- .release = dynamic_kobj_release,
- .sysfs_ops = &kobj_sysfs_ops,
- };
- /**
- * 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.
- *
- * 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() has
- * already been called on this structure.
- */
- static struct kobject *kobject_create(void)
- {
- struct kobject *kobj;
- kobj = kzalloc(sizeof(*kobj), GFP_KERNEL);
- if (!kobj)
- return NULL;
- kobject_init(kobj, &dynamic_kobj_ktype);
- return kobj;
- }
- /**
- * kobject_create_and_add() - Create a struct kobject dynamically and
- * register it with sysfs.
- * @name: the name for the kobject
- * @parent: the parent kobject of this kobject, if any.
- *
- * This function creates a kobject structure dynamically and registers it
- * with sysfs. When you are finished with this structure, call
- * kobject_put() 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_create_and_add(const char *name, struct kobject *parent)
- {
- struct kobject *kobj;
- int retval;
- kobj = kobject_create();
- if (!kobj)
- return NULL;
- retval = kobject_add(kobj, parent, "%s", name);
- if (retval) {
- pr_warn("%s: kobject_add error: %d\n", __func__, retval);
- kobject_put(kobj);
- kobj = NULL;
- }
- return kobj;
- }
- EXPORT_SYMBOL_GPL(kobject_create_and_add);
- /**
- * kset_init() - Initialize a kset for use.
- * @k: kset
- */
- void kset_init(struct kset *k)
- {
- kobject_init_internal(&k->kobj);
- INIT_LIST_HEAD(&k->list);
- 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;
- }
- const struct sysfs_ops kobj_sysfs_ops = {
- .show = kobj_attr_show,
- .store = kobj_attr_store,
- };
- EXPORT_SYMBOL_GPL(kobj_sysfs_ops);
- /**
- * kset_register() - Initialize and add a kset.
- * @k: kset.
- */
- int kset_register(struct kset *k)
- {
- int err;
- if (!k)
- return -EINVAL;
- if (!k->kobj.ktype) {
- pr_err("must have a ktype to be initialized properly!\n");
- return -EINVAL;
- }
- kset_init(k);
- err = kobject_add_internal(&k->kobj);
- if (err)
- return err;
- kobject_uevent(&k->kobj, KOBJ_ADD);
- return 0;
- }
- EXPORT_SYMBOL(kset_register);
- /**
- * kset_unregister() - Remove a kset.
- * @k: kset.
- */
- void kset_unregister(struct kset *k)
- {
- if (!k)
- return;
- kobject_del(&k->kobj);
- kobject_put(&k->kobj);
- }
- EXPORT_SYMBOL(kset_unregister);
- /**
- * kset_find_obj() - Search for object in kset.
- * @kset: kset we're looking in.
- * @name: object's name.
- *
- * Lock kset via @kset->subsys, and iterate over @kset->list,
- * looking for a matching kobject. If matching object is found
- * take a reference and return the object.
- */
- struct kobject *kset_find_obj(struct kset *kset, const char *name)
- {
- struct kobject *k;
- struct kobject *ret = NULL;
- spin_lock(&kset->list_lock);
- list_for_each_entry(k, &kset->list, entry) {
- if (kobject_name(k) && !strcmp(kobject_name(k), name)) {
- ret = kobject_get_unless_zero(k);
- break;
- }
- }
- spin_unlock(&kset->list_lock);
- return ret;
- }
- EXPORT_SYMBOL_GPL(kset_find_obj);
- static void kset_release(struct kobject *kobj)
- {
- struct kset *kset = container_of(kobj, struct kset, kobj);
- pr_debug("kobject: '%s' (%p): %s\n",
- kobject_name(kobj), kobj, __func__);
- kfree(kset);
- }
- static void kset_get_ownership(struct kobject *kobj, kuid_t *uid, kgid_t *gid)
- {
- if (kobj->parent)
- kobject_get_ownership(kobj->parent, uid, gid);
- }
- static struct kobj_type kset_ktype = {
- .sysfs_ops = &kobj_sysfs_ops,
- .release = kset_release,
- .get_ownership = kset_get_ownership,
- };
- /**
- * 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.
- */
- static struct kset *kset_create(const char *name,
- const struct kset_uevent_ops *uevent_ops,
- struct kobject *parent_kobj)
- {
- struct kset *kset;
- int retval;
- kset = kzalloc(sizeof(*kset), GFP_KERNEL);
- if (!kset)
- return NULL;
- retval = kobject_set_name(&kset->kobj, "%s", name);
- if (retval) {
- kfree(kset);
- return NULL;
- }
- 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;
- }
- /**
- * 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,
- const 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 kset;
- }
- EXPORT_SYMBOL_GPL(kset_create_and_add);
- static DEFINE_SPINLOCK(kobj_ns_type_lock);
- static const struct kobj_ns_type_operations *kobj_ns_ops_tbl[KOBJ_NS_TYPES];
- int kobj_ns_type_register(const struct kobj_ns_type_operations *ops)
- {
- enum kobj_ns_type type = ops->type;
- int error;
- spin_lock(&kobj_ns_type_lock);
- error = -EINVAL;
- if (type >= KOBJ_NS_TYPES)
- goto out;
- error = -EINVAL;
- if (type <= KOBJ_NS_TYPE_NONE)
- goto out;
- error = -EBUSY;
- if (kobj_ns_ops_tbl[type])
- goto out;
- error = 0;
- kobj_ns_ops_tbl[type] = ops;
- out:
- spin_unlock(&kobj_ns_type_lock);
- return error;
- }
- int kobj_ns_type_registered(enum kobj_ns_type type)
- {
- int registered = 0;
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES))
- registered = kobj_ns_ops_tbl[type] != NULL;
- spin_unlock(&kobj_ns_type_lock);
- return registered;
- }
- const struct kobj_ns_type_operations *kobj_child_ns_ops(struct kobject *parent)
- {
- const struct kobj_ns_type_operations *ops = NULL;
- if (parent && parent->ktype && parent->ktype->child_ns_type)
- ops = parent->ktype->child_ns_type(parent);
- return ops;
- }
- const struct kobj_ns_type_operations *kobj_ns_ops(struct kobject *kobj)
- {
- return kobj_child_ns_ops(kobj->parent);
- }
- bool kobj_ns_current_may_mount(enum kobj_ns_type type)
- {
- bool may_mount = true;
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
- kobj_ns_ops_tbl[type])
- may_mount = kobj_ns_ops_tbl[type]->current_may_mount();
- spin_unlock(&kobj_ns_type_lock);
- return may_mount;
- }
- void *kobj_ns_grab_current(enum kobj_ns_type type)
- {
- void *ns = NULL;
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
- kobj_ns_ops_tbl[type])
- ns = kobj_ns_ops_tbl[type]->grab_current_ns();
- spin_unlock(&kobj_ns_type_lock);
- return ns;
- }
- EXPORT_SYMBOL_GPL(kobj_ns_grab_current);
- const void *kobj_ns_netlink(enum kobj_ns_type type, struct sock *sk)
- {
- const void *ns = NULL;
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
- kobj_ns_ops_tbl[type])
- ns = kobj_ns_ops_tbl[type]->netlink_ns(sk);
- spin_unlock(&kobj_ns_type_lock);
- return ns;
- }
- const void *kobj_ns_initial(enum kobj_ns_type type)
- {
- const void *ns = NULL;
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
- kobj_ns_ops_tbl[type])
- ns = kobj_ns_ops_tbl[type]->initial_ns();
- spin_unlock(&kobj_ns_type_lock);
- return ns;
- }
- void kobj_ns_drop(enum kobj_ns_type type, void *ns)
- {
- spin_lock(&kobj_ns_type_lock);
- if ((type > KOBJ_NS_TYPE_NONE) && (type < KOBJ_NS_TYPES) &&
- kobj_ns_ops_tbl[type] && kobj_ns_ops_tbl[type]->drop_ns)
- kobj_ns_ops_tbl[type]->drop_ns(ns);
- spin_unlock(&kobj_ns_type_lock);
- }
- EXPORT_SYMBOL_GPL(kobj_ns_drop);
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