Something went wrong. Try again.
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Something went wrong. Try again.
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586878889909192939495969798991001011021031041051061071081091101111121131141151161171181191201211221231241251261271281291301311321331341351361371381391401411421431441451461471481491501511521531541551561571581591601611621631641651661671681691701711721731741751761771781791801811821831841851861871881891901911921931941951961971981992002012022032042052062072082092102112122132142152162172182192202212222232242252262272282292302312322332342352362372382392402412422432442452462472482492502512522532542552562572582592602612622632642652662672682692702712722732742752762772782792802812822832842852862872882892902912922932942952962972982993003013023033043053063073083093103113123133143153163173183193203213223233243253263273283293303313323333343353363373383393403413423433443453463473483493503513523533543553563573583593603613623633643653663673683693703713723733743753763773783793803813823833843853863873883893903913923933943953963973983994004014024034044054064074084094104114124134144154164174184194204214224234244254264274284294304314324334344354364374384394404414424434444454464474484494504514524534544554564574584594604614624634644654664674684694704714724734744754764774784794804814824834844854864874884894904914924934944954964974984995005015025035045055065075085095105115125135145155165175185195205215225235245255265275285295305315325335345355365375385395405415425435445455465475485495505515525535545555565575585595605615625635645655665675685695705715725735745755765775785795805815825835845855865875885895905915925935945955965975985996006016026036046056066076086096106116126136146156166176186196206216226236246256266276286296306316326336346356366376386396406416426436446456466476486496506516526536546556566576586596606616626636646656666676686696706716726736746756766776786796806816826836846856866876886896906916926936946956966976986997007017027037047057067077087097107117127137147157167177187197207217227237247257267277287297307317327337347357367377387397407417427437447457467477487497507517527537547557567577587597607617627637647657667677687697707717727737747757767777787797807817827837847857867877887897907917927937947957967977987998008018028038048058068078088098108118128138148158168178188198208218228238248258268278288298308318328338348358368378388398408418428438448458468478488498508518528538548558568578588598608618628638648658668678688698708718728738748758768778788798808818828838848858868878888898908918928938948958968978988999009019029039049059069079089099109119129139149159169179189199209219229239249259269279289299309319329339349359369379389399409419429439449459469479489499509519529539549559569579589599609619629639649659669679689699709719729739749759769779789799809819829839849859869879889899909919929939949959969979989991000100110021003100410051006100710081009101010111012101310141015101610171018101910201021102210231024102510261027102810291030103110321033103410351036103710381039104010411042104310441045104610471048104910501051105210531054105510561057105810591060106110621063106410651066106710681069107010711072107310741075107610771078107910801081108210831084108510861087108810891090109110921093109410951096109710981099110011011102110311041105110611071108// SPDX-License-Identifier: GPL-2.0/* * 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. * * Please see the file Documentation/core-api/kobject.rst for critical information * about using the kobject interface. */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#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 struct ns_common *kobject_namespace(const 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(const 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 bool kobj_ns_type_is_valid(enum kobj_ns_type type){ if ((type <= KOBJ_NS_TYPE_NONE) || (type >= KOBJ_NS_TYPES)) return false;
return true;}
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(!kobj_ns_type_is_valid(ops->type)); 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("'%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("'%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; s = strreplace(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_lvl(KERN_ERR); }
kobject_init_internal(kobj); kobj->ktype = ktype; return;
error: pr_err("kobject (%p): %s\n", kobj, err_str); dump_stack_lvl(KERN_ERR);}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("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_lvl(KERN_ERR); 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("'%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("'%s' (%p): %s, parent %p\n", kobject_name(kobj), kobj, __func__, kobj->parent);
if (t && !t->release) pr_debug("'%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("'%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("'%s' (%p): calling ktype release\n", kobject_name(kobj), kobj); t->release(kobj); }
/* free name if we allocated it */ if (name) { pr_debug("'%s': free name\n", name); kfree_const(name); }
kobject_put(parent);}
#ifdef CONFIG_DEBUG_KOBJECT_RELEASEstatic 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_u32_below(4); pr_info("'%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("(%p): %s\n", kobj, __func__); kfree(kobj);}
static const 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_obj(*kobj); 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. * * NOTE: On error, the kset.kobj.name allocated by() kobj_set_name() * is freed, it can not be used any more. */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) { kfree_const(k->kobj.name); /* Set it to NULL to avoid accessing bad pointer in callers. */ k->kobj.name = NULL; 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("'%s' (%p): %s\n", kobject_name(kobj), kobj, __func__); kfree(kset);}
static void kset_get_ownership(const struct kobject *kobj, kuid_t *uid, kgid_t *gid){ if (kobj->parent) kobject_get_ownership(kobj->parent, uid, gid);}
static const 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_obj(*kset); 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 (!kobj_ns_type_is_valid(type)) 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 (kobj_ns_type_is_valid(type)) 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(const 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(const 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 (kobj_ns_type_is_valid(type) && kobj_ns_ops_tbl[type]) may_mount = kobj_ns_ops_tbl[type]->current_may_mount(); spin_unlock(&kobj_ns_type_lock);
return may_mount;}
struct ns_common *kobj_ns_grab_current(enum kobj_ns_type type){ struct ns_common *ns = NULL;
spin_lock(&kobj_ns_type_lock); if (kobj_ns_type_is_valid(type) && 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);
void kobj_ns_drop(enum kobj_ns_type type, struct ns_common *ns){ spin_lock(&kobj_ns_type_lock); if (kobj_ns_type_is_valid(type) && 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);