| /* |
| * 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. |
| * |
| * |
| * Please see the file Documentation/kobject.txt 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); |
| } |
| |
| /* |
| * populate_dir - populate directory with attributes. |
| * @kobj: object we're working on. |
| * |
| * Most subsystems have a set of default attributes that are associated |
| * with an object that registers with them. This is a helper called during |
| * object registration that loops through the default attributes of the |
| * subsystem and creates attributes files for them in sysfs. |
| */ |
| static int populate_dir(struct kobject *kobj) |
| { |
| struct kobj_type *t = get_ktype(kobj); |
| struct attribute *attr; |
| int error = 0; |
| int i; |
| |
| if (t && t->default_attrs) { |
| for (i = 0; (attr = t->default_attrs[i]) != NULL; i++) { |
| error = sysfs_create_file(kobj, attr); |
| if (error) |
| break; |
| } |
| } |
| return error; |
| } |
| |
| static int create_dir(struct kobject *kobj) |
| { |
| const struct kobj_ns_type_operations *ops; |
| int error; |
| |
| error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj)); |
| if (error) |
| return error; |
| |
| error = populate_dir(kobj); |
| 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(struct kobject *kobj) |
| { |
| int length = 1; |
| 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 void fill_kobj_path(struct kobject *kobj, char *path, int length) |
| { |
| 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; |
| strncpy(path + length, kobject_name(parent), cur); |
| *(path + --length) = '/'; |
| } |
| |
| pr_debug("kobject: '%s' (%p): %s: path = '%s'\n", kobject_name(kobj), |
| kobj, __func__, path); |
| } |
| |
| /** |
| * kobject_get_path - generate and return the path associated with a given kobj and kset pair. |
| * |
| * @kobj: kobject in question, with which to build the path |
| * @gfp_mask: the allocation type used to allocate the path |
| * |
| * The result must be freed by the caller with kfree(). |
| */ |
| char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask) |
| { |
| char *path; |
| int len; |
| |
| len = get_kobj_path_length(kobj); |
| if (len == 0) |
| return NULL; |
| path = kzalloc(len, gfp_mask); |
| if (!path) |
| return NULL; |
| fill_kobj_path(kobj, path, len); |
| |
| 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 an 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, 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 */ |
| printk(KERN_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: |
| printk(KERN_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) { |
| printk(KERN_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. |
| * |
| * 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. |
| * |
| * 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. |
| */ |
| 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) { |
| printk(KERN_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(). 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, 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) |
| 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); |
| |
| /** |
| * kobject_del - unlink kobject from hierarchy. |
| * @kobj: object. |
| */ |
| void kobject_del(struct kobject *kobj) |
| { |
| struct kernfs_node *sd; |
| |
| if (!kobj) |
| return; |
| |
| sd = kobj->sd; |
| sysfs_remove_dir(kobj); |
| sysfs_put(sd); |
| |
| kobj->state_in_sysfs = 0; |
| kobj_kset_leave(kobj); |
| kobject_put(kobj->parent); |
| kobj->parent = NULL; |
| } |
| 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); |
| |
| static struct kobject * __must_check kobject_get_unless_zero(struct kobject *kobj) |
| { |
| if (!kref_get_unless_zero(&kobj->kref)) |
| kobj = NULL; |
| return kobj; |
| } |
| |
| /* |
| * kobject_cleanup - free kobject resources. |
| * @kobj: object to cleanup |
| */ |
| static void kobject_cleanup(struct kobject *kobj) |
| { |
| 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.\n", |
| kobject_name(kobj), kobj); |
| |
| /* 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); |
| } |
| |
| /* 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); |
| } |
| |
| 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); |
| } |
| } |
| |
| #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 * (get_random_int() & 0x3); |
| 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. |
| */ |
| 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) { |
| printk(KERN_WARNING "%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; |
| |
| 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; |
| } |
| |
| 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 struct kobj_type kset_ktype = { |
| .sysfs_ops = &kobj_sysfs_ops, |
| .release = kset_release, |
| }; |
| |
| /** |
| * 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; |
| } |
| |
| 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); |
| } |