diff options
| -rw-r--r-- | drivers/base/core.c | 32 | ||||
| -rw-r--r-- | include/linux/kobject.h | 5 | ||||
| -rw-r--r-- | lib/kobject.c | 170 | ||||
| -rw-r--r-- | lib/kobject_uevent.c | 11 |
4 files changed, 119 insertions, 99 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c index 675a719..d5d542d 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -576,8 +576,8 @@ static struct kobject *get_device_parent(struct device *dev, /* * If we have no parent, we live in "virtual". - * Class-devices with a bus-device as parent, live - * in a class-directory to prevent namespace collisions. + * Class-devices with a non class-device as parent, live + * in a "glue" directory to prevent namespace collisions. */ if (parent == NULL) parent_kobj = virtual_device_parent(dev); @@ -607,8 +607,7 @@ static struct kobject *get_device_parent(struct device *dev, kobject_put(k); return NULL; } - /* Do not emit a uevent, as it's not needed for this - * "class glue" directory. */ + /* do not emit an uevent for this simple "glue" directory */ return k; } @@ -619,30 +618,13 @@ static struct kobject *get_device_parent(struct device *dev, static void cleanup_device_parent(struct device *dev) { - struct device *d; - int other = 0; + struct kobject *glue_dir = dev->kobj.parent; - if (!dev->class) - return; - - /* see if we live in a parent class directory */ - if (dev->kobj.parent->kset != &dev->class->class_dirs) + /* see if we live in a "glue" directory */ + if (!dev->class || glue_dir->kset != &dev->class->class_dirs) return; - /* if we are the last child of our class, delete the directory */ - down(&dev->class->sem); - list_for_each_entry(d, &dev->class->devices, node) { - if (d == dev) - continue; - if (d->kobj.parent == dev->kobj.parent) { - other = 1; - break; - } - } - if (!other) - kobject_del(dev->kobj.parent); - kobject_put(dev->kobj.parent); - up(&dev->class->sem); + kobject_put(glue_dir); } #endif diff --git a/include/linux/kobject.h b/include/linux/kobject.h index 63967da..be03ce8 100644 --- a/include/linux/kobject.h +++ b/include/linux/kobject.h @@ -68,6 +68,11 @@ struct kobject { struct kset * kset; struct kobj_type * ktype; struct sysfs_dirent * sd; + unsigned int state_initialized:1; + unsigned int state_name_set:1; + unsigned int state_in_sysfs:1; + unsigned int state_add_uevent_sent:1; + unsigned int state_remove_uevent_sent:1; }; extern int kobject_set_name(struct kobject *, const char *, ...) diff --git a/lib/kobject.c b/lib/kobject.c index c321f19..4fce5ca 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -124,85 +124,74 @@ char *kobject_get_path(struct kobject *kobj, gfp_t gfp_mask) } EXPORT_SYMBOL_GPL(kobject_get_path); -static void kobject_init_internal(struct kobject * kobj) +/* add the kobject to its kset's list */ +static void kobj_kset_join(struct kobject *kobj) { - if (!kobj) + if (!kobj->kset) return; - kref_init(&kobj->kref); - INIT_LIST_HEAD(&kobj->entry); + + 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; -/** - * 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_internal() on error. - */ + spin_lock(&kobj->kset->list_lock); + list_del_init(&kobj->entry); + spin_unlock(&kobj->kset->list_lock); + kset_put(kobj->kset); +} -static void unlink(struct kobject * kobj) +static void kobject_init_internal(struct kobject * kobj) { - struct kobject *parent = kobj->parent; - - if (kobj->kset) { - spin_lock(&kobj->kset->list_lock); - list_del_init(&kobj->entry); - spin_unlock(&kobj->kset->list_lock); - } - kobj->parent = NULL; - kobject_put(kobj); - kobject_put(parent); + if (!kobj) + return; + kref_init(&kobj->kref); + INIT_LIST_HEAD(&kobj->entry); } + static int kobject_add_internal(struct kobject *kobj) { int error = 0; struct kobject * parent; - if (!(kobj = kobject_get(kobj))) + if (!kobj) return -ENOENT; - if (!kobj->k_name) - kobject_set_name(kobj, "NO_NAME"); - if (!*kobj->k_name) { - pr_debug("kobject (%p) attempted to be registered with no " + + if (!kobj->k_name || !kobj->k_name[0]) { + pr_debug("kobject: (%p): attempted to be registered with empty " "name!\n", kobj); WARN_ON(1); - kobject_put(kobj); return -EINVAL; } - parent = kobject_get(kobj->parent); - pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n", - kobject_name(kobj), kobj, __FUNCTION__, - parent ? kobject_name(parent) : "<NULL>", - kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" ); + parent = kobject_get(kobj->parent); + /* join kset if set, use it as parent if we do not already have one */ if (kobj->kset) { - kobj->kset = kset_get(kobj->kset); - - if (!parent) { + if (!parent) parent = kobject_get(&kobj->kset->kobj); - /* - * If the kset is our parent, get a second - * reference, we drop both the kset and the - * parent ref on cleanup - */ - kobject_get(parent); - } - - spin_lock(&kobj->kset->list_lock); - list_add_tail(&kobj->entry, &kobj->kset->list); - spin_unlock(&kobj->kset->list_lock); + kobj_kset_join(kobj); kobj->parent = parent; } + pr_debug("kobject: '%s' (%p): %s: parent: '%s', set: '%s'\n", + kobject_name(kobj), kobj, __FUNCTION__, + parent ? kobject_name(parent) : "<NULL>", + kobj->kset ? kobject_name(&kobj->kset->kobj) : "<NULL>" ); + error = create_dir(kobj); if (error) { - /* unlink does the kobject_put() for us */ - unlink(kobj); + kobj_kset_leave(kobj); + kobject_put(parent); + kobj->parent = NULL; /* be noisy on error issues */ if (error == -EEXIST) @@ -214,7 +203,8 @@ static int kobject_add_internal(struct kobject *kobj) printk(KERN_ERR "%s failed for %s (%d)\n", __FUNCTION__, kobject_name(kobj), error); dump_stack(); - } + } else + kobj->state_in_sysfs = 1; return error; } @@ -238,11 +228,13 @@ static int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, if (!name) return -ENOMEM; + /* Free the old name, if necessary. */ kfree(kobj->k_name); /* Now, set the new name */ kobj->k_name = name; + kobj->state_name_set = 1; return 0; } @@ -293,20 +285,25 @@ void kobject_init(struct kobject *kobj, struct kobj_type *ktype) err_str = "must have a ktype to be initialized properly!\n"; goto error; } - if (atomic_read(&kobj->kref.refcount)) { + if (kobj->state_initialized) { /* do not error out as sometimes we can recover */ - printk(KERN_ERR "kobject: reference count is already set, " - "something is seriously wrong.\n"); + printk(KERN_ERR "kobject (%p): tried to init an initialized " + "object, something is seriously wrong.\n", kobj); dump_stack(); } kref_init(&kobj->kref); INIT_LIST_HEAD(&kobj->entry); kobj->ktype = ktype; + kobj->state_name_set = 0; + kobj->state_in_sysfs = 0; + kobj->state_add_uevent_sent = 0; + kobj->state_remove_uevent_sent = 0; + kobj->state_initialized = 1; return; error: - printk(KERN_ERR "kobject: %s\n", err_str); + printk(KERN_ERR "kobject (%p): %s\n", kobj, err_str); dump_stack(); } EXPORT_SYMBOL(kobject_init); @@ -345,17 +342,10 @@ static int kobject_add_varg(struct kobject *kobj, struct kobject *parent, * * If this function returns an error, kobject_put() must be called to * properly clean up the memory associated with the object. - * - * If the function is successful, the only way to properly clean up the - * memory is with a call to kobject_del(), in which case, a call to - * kobject_put() is not necessary (kobject_del() does the final - * kobject_put() to call the release function in the ktype's release - * pointer.) - * * Under no instance should the kobject that is passed to this function * be directly freed with a call to kfree(), that can leak memory. * - * Note, no uevent will be created with this call, the caller should set + * 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. @@ -369,6 +359,13 @@ int kobject_add(struct kobject *kobj, struct kobject *parent, 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); @@ -527,8 +524,12 @@ void kobject_del(struct kobject * kobj) { if (!kobj) return; + sysfs_remove_dir(kobj); - unlink(kobj); + kobj->state_in_sysfs = 0; + kobj_kset_leave(kobj); + kobject_put(kobj->parent); + kobj->parent = NULL; } /** @@ -565,21 +566,43 @@ struct kobject * kobject_get(struct kobject * kobj) */ static void kobject_cleanup(struct kobject *kobj) { - struct kobj_type * t = get_ktype(kobj); - struct kset * s = kobj->kset; + struct kobj_type *t = get_ktype(kobj); const char *name = kobj->k_name; + int name_set = kobj->state_name_set; pr_debug("kobject: '%s' (%p): %s\n", kobject_name(kobj), kobj, __FUNCTION__); + + 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); - /* If we have a release function, we can guess that this was - * not a statically allocated kobject, so we should be safe to - * free the name */ + } + + /* free name if we allocated it */ + if (name_set && name) { + pr_debug("kobject: '%s': free name\n", name); kfree(name); } - if (s) - kset_put(s); } static void kobject_release(struct kref *kref) @@ -601,8 +624,7 @@ void kobject_put(struct kobject * kobj) static void dynamic_kobj_release(struct kobject *kobj) { - pr_debug("kobject: '%s' (%p): %s\n", - kobject_name(kobj), kobj, __FUNCTION__); + pr_debug("kobject: (%p): %s\n", kobj, __FUNCTION__); kfree(kobj); } diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index 51dc4d2..b021e67 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -180,6 +180,17 @@ int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, } } + /* + * Mark "add" and "remove" events in the object to ensure proper + * events to userspace during automatic cleanup. If the object did + * send an "add" event, "remove" will automatically generated by + * the core, if not already done by the caller. + */ + if (action == KOBJ_ADD) + kobj->state_add_uevent_sent = 1; + else if (action == KOBJ_REMOVE) + kobj->state_remove_uevent_sent = 1; + /* we will send an event, so request a new sequence number */ spin_lock(&sequence_lock); seq = ++uevent_seqnum; |
