/* * kobject.c - library routines for handling generic kernel objects * * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org> * * 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/module.h>#include <linux/stat.h>#include <linux/slab.h> /** * 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++) { if ((error = sysfs_create_file(kobj,attr))) break; } } return error;} static int create_dir(struct kobject * kobj, struct dentry *shadow_parent){ int error = 0; if (kobject_name(kobj)) { error = sysfs_create_dir(kobj, shadow_parent); if (!error) { if ((error = populate_dir(kobj))) sysfs_remove_dir(kobj); } } return error;} static inline struct kobject * to_kobj(struct list_head * entry){ return container_of(entry,struct kobject,entry);} 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("%s: path = '%s'\n",__FUNCTION__,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); /** * kobject_init - initialize object. * @kobj: object in question. */void kobject_init(struct kobject * kobj){ if (!kobj) return; kref_init(&kobj->kref); INIT_LIST_HEAD(&kobj->entry); init_waitqueue_head(&kobj->poll); kobj->kset = kset_get(kobj->kset);} /** * unlink - remove kobject from kset list. * @kobj: kobject. * * Remove the kobject from the kset list and decrement * its parent's refcount. * This is separated out, so we can use it in both * kobject_del() and kobject_add() on error. */ static void unlink(struct kobject * kobj){ if (kobj->kset) { spin_lock(&kobj->kset->list_lock); list_del_init(&kobj->entry); spin_unlock(&kobj->kset->list_lock); } kobject_put(kobj);} /** * 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 dentry *shadow_parent){ int error = 0; struct kobject * parent; if (!(kobj = kobject_get(kobj))) return -ENOENT; if (!kobj->k_name) kobj->k_name = kobj->name; if (!*kobj->k_name) { pr_debug("kobject attempted to be registered with no name!\n"); WARN_ON(1); return -EINVAL; } parent = kobject_get(kobj->parent); 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>" ); if (kobj->kset) { spin_lock(&kobj->kset->list_lock); if (!parent) parent = kobject_get(&kobj->kset->kobj); list_add_tail(&kobj->entry,&kobj->kset->list); spin_unlock(&kobj->kset->list_lock); } kobj->parent = parent; error = create_dir(kobj, shadow_parent); if (error) { /* unlink does the kobject_put() for us */ unlink(kobj); kobject_put(parent); /* be noisy on error issues */ if (error == -EEXIST) printk("kobject_add failed for %s with -EEXIST, " "don't try to register things with the " "same name in the same directory.\n", kobject_name(kobj)); else printk("kobject_add failed for %s (%d)\n", kobject_name(kobj), error); dump_stack(); } 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. */ int kobject_register(struct kobject * kobj){ int error = -EINVAL; if (kobj) { kobject_init(kobj); error = kobject_add(kobj); if (!error) kobject_uevent(kobj, KOBJ_ADD); } return error;} /** * kobject_set_name - Set the name of an object * @kobj: object. * @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. */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; /* * First, try the static array */ va_start(args,fmt); need = vsnprintf(kobj->name,limit,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; } } /* Free the old name, if necessary. */ if (kobj->k_name && kobj->k_name != kobj->name) kfree(kobj->k_name); /* Now, set the new name */ kobj->k_name = name; Done: return error;} EXPORT_SYMBOL(kobject_set_name); /** * kobject_rename - change the name of an object * @kobj: object in question. * @new_name: object's new name */ int kobject_rename(struct kobject * kobj, const char *new_name){ int error = 0; kobj = kobject_get(kobj); if (!kobj) return -EINVAL; if (!kobj->parent) return -EINVAL; error = sysfs_rename_dir(kobj, kobj->parent->dentry, new_name); kobject_put(kobj); 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 dentry *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. * @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(kobj, new_parent); 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;} /** * kobject_del - unlink kobject from hierarchy. * @kobj: object. */ void kobject_del(struct kobject * kobj){ if (!kobj) return; sysfs_remove_dir(kobj); unlink(kobj);} /** * kobject_unregister - remove object from hierarchy and decrement refcount. * @kobj: object going away. */ void kobject_unregister(struct kobject * kobj){ if (!kobj) return; pr_debug("kobject %s: unregistering\n",kobject_name(kobj)); kobject_uevent(kobj, KOBJ_REMOVE); kobject_del(kobj); kobject_put(kobj);} /** * kobject_get - increment refcount for object. * @kobj: object. */ struct kobject * kobject_get(struct kobject * kobj){ if (kobj) kref_get(&kobj->kref); return kobj;} /** * kobject_cleanup - free kobject resources. * @kobj: object. */ void kobject_cleanup(struct kobject * kobj){ struct kobj_type * t = get_ktype(kobj); struct kset * s = kobj->kset; struct kobject * parent = kobj->parent; 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) t->release(kobj); if (s) kset_put(s); kobject_put(parent);} static void kobject_release(struct kref *kref){ kobject_cleanup(container_of(kref, struct kobject, kref));} /** * 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) kref_put(&kobj->kref, kobject_release);} static void dir_release(struct kobject *kobj){ kfree(kobj);} static struct kobj_type dir_ktype = { .release = dir_release, .sysfs_ops = NULL, .default_attrs = NULL,}; /** * kobject_add_dir - add sub directory of object. * @parent: object in which a directory is created. * @name: directory name. * * Add a plain directory object as child of given object. */struct kobject *kobject_add_dir(struct kobject *parent, const char *name){ struct kobject *k; int ret;Lines 1–500 of 704. 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/* * kobject.c - library routines for handling generic kernel objects * * Copyright (c) 2002-2003 Patrick Mochel <mochel@osdl.org> * * 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/module.h> #include <linux/stat.h> #include <linux/slab.h> /** * 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++) { if ((error = sysfs_create_file(kobj,attr))) break; } } return error; } static int create_dir(struct kobject * kobj, struct dentry *shadow_parent) { int error = 0; if (kobject_name(kobj)) { error = sysfs_create_dir(kobj, shadow_parent); if (!error) { if ((error = populate_dir(kobj))) sysfs_remove_dir(kobj); } } return error; } static inline struct kobject * to_kobj(struct list_head * entry) { return container_of(entry,struct kobject,entry); } 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("%s: path = '%s'\n",__FUNCTION__,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); /** * kobject_init - initialize object. * @kobj: object in question. */ void kobject_init(struct kobject * kobj) { if (!kobj) return; kref_init(&kobj->kref); INIT_LIST_HEAD(&kobj->entry); init_waitqueue_head(&kobj->poll); kobj->kset = kset_get(kobj->kset); } /** * unlink - remove kobject from kset list. * @kobj: kobject. * * Remove the kobject from the kset list and decrement * its parent's refcount. * This is separated out, so we can use it in both * kobject_del() and kobject_add() on error. */ static void unlink(struct kobject * kobj) { if (kobj->kset) { spin_lock(&kobj->kset->list_lock); list_del_init(&kobj->entry); spin_unlock(&kobj->kset->list_lock); } kobject_put(kobj); } /** * 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 dentry *shadow_parent) { int error = 0; struct kobject * parent; if (!(kobj = kobject_get(kobj))) return -ENOENT; if (!kobj->k_name) kobj->k_name = kobj->name; if (!*kobj->k_name) { pr_debug("kobject attempted to be registered with no name!\n"); WARN_ON(1); return -EINVAL; } parent = kobject_get(kobj->parent); 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>" ); if (kobj->kset) { spin_lock(&kobj->kset->list_lock); if (!parent) parent = kobject_get(&kobj->kset->kobj); list_add_tail(&kobj->entry,&kobj->kset->list); spin_unlock(&kobj->kset->list_lock); } kobj->parent = parent; error = create_dir(kobj, shadow_parent); if (error) { /* unlink does the kobject_put() for us */ unlink(kobj); kobject_put(parent); /* be noisy on error issues */ if (error == -EEXIST) printk("kobject_add failed for %s with -EEXIST, " "don't try to register things with the " "same name in the same directory.\n", kobject_name(kobj)); else printk("kobject_add failed for %s (%d)\n", kobject_name(kobj), error); dump_stack(); } 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. */ int kobject_register(struct kobject * kobj) { int error = -EINVAL; if (kobj) { kobject_init(kobj); error = kobject_add(kobj); if (!error) kobject_uevent(kobj, KOBJ_ADD); } return error; } /** * kobject_set_name - Set the name of an object * @kobj: object. * @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. */ 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; /* * First, try the static array */ va_start(args,fmt); need = vsnprintf(kobj->name,limit,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; } } /* Free the old name, if necessary. */ if (kobj->k_name && kobj->k_name != kobj->name) kfree(kobj->k_name); /* Now, set the new name */ kobj->k_name = name; Done: return error; } EXPORT_SYMBOL(kobject_set_name); /** * kobject_rename - change the name of an object * @kobj: object in question. * @new_name: object's new name */ int kobject_rename(struct kobject * kobj, const char *new_name) { int error = 0; kobj = kobject_get(kobj); if (!kobj) return -EINVAL; if (!kobj->parent) return -EINVAL; error = sysfs_rename_dir(kobj, kobj->parent->dentry, new_name); kobject_put(kobj); 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 dentry *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. * @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(kobj, new_parent); 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; } /** * kobject_del - unlink kobject from hierarchy. * @kobj: object. */ void kobject_del(struct kobject * kobj) { if (!kobj) return; sysfs_remove_dir(kobj); unlink(kobj); } /** * kobject_unregister - remove object from hierarchy and decrement refcount. * @kobj: object going away. */ void kobject_unregister(struct kobject * kobj) { if (!kobj) return; pr_debug("kobject %s: unregistering\n",kobject_name(kobj)); kobject_uevent(kobj, KOBJ_REMOVE); kobject_del(kobj); kobject_put(kobj); } /** * kobject_get - increment refcount for object. * @kobj: object. */ struct kobject * kobject_get(struct kobject * kobj) { if (kobj) kref_get(&kobj->kref); return kobj; } /** * kobject_cleanup - free kobject resources. * @kobj: object. */ void kobject_cleanup(struct kobject * kobj) { struct kobj_type * t = get_ktype(kobj); struct kset * s = kobj->kset; struct kobject * parent = kobj->parent; 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) t->release(kobj); if (s) kset_put(s); kobject_put(parent); } static void kobject_release(struct kref *kref) { kobject_cleanup(container_of(kref, struct kobject, kref)); } /** * 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) kref_put(&kobj->kref, kobject_release); } static void dir_release(struct kobject *kobj) { kfree(kobj); } static struct kobj_type dir_ktype = { .release = dir_release, .sysfs_ops = NULL, .default_attrs = NULL, }; /** * kobject_add_dir - add sub directory of object. * @parent: object in which a directory is created. * @name: directory name. * * Add a plain directory object as child of given object. */ struct kobject *kobject_add_dir(struct kobject *parent, const char *name) { struct kobject *k; int ret;