diff options
Diffstat (limited to 'lib/kobject.c')
| -rw-r--r-- | lib/kobject.c | 124 |
1 files changed, 117 insertions, 7 deletions
diff --git a/lib/kobject.c b/lib/kobject.c index 4a1f33d43548..5b4b8886435e 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -13,11 +13,30 @@ */ #include <linux/kobject.h> +#include <linux/kobj_completion.h> #include <linux/string.h> #include <linux/export.h> #include <linux/stat.h> #include <linux/slab.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. @@ -46,13 +65,21 @@ static int populate_dir(struct kobject *kobj) static int create_dir(struct kobject *kobj) { - int error = 0; - error = sysfs_create_dir(kobj); + int error; + + error = sysfs_create_dir_ns(kobj, kobject_namespace(kobj)); if (!error) { error = populate_dir(kobj); if (error) sysfs_remove_dir(kobj); } + + /* + * @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); + return error; } @@ -428,7 +455,7 @@ int kobject_rename(struct kobject *kobj, const char *new_name) goto out; } - error = sysfs_rename_dir(kobj, new_name); + error = sysfs_rename_dir_ns(kobj, new_name, kobject_namespace(kobj)); if (error) goto out; @@ -472,6 +499,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent) if (kobj->kset) new_parent = kobject_get(&kobj->kset->kobj); } + /* old object path */ devpath = kobject_get_path(kobj, GFP_KERNEL); if (!devpath) { @@ -486,7 +514,7 @@ int kobject_move(struct kobject *kobj, struct kobject *new_parent) sprintf(devpath_string, "DEVPATH_OLD=%s", devpath); envp[0] = devpath_string; envp[1] = NULL; - error = sysfs_move_dir(kobj, new_parent); + error = sysfs_move_dir_ns(kobj, new_parent, kobject_namespace(kobj)); if (error) goto out; old_parent = kobj->parent; @@ -508,10 +536,15 @@ out: */ void kobject_del(struct kobject *kobj) { + struct sysfs_dirent *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); @@ -545,8 +578,8 @@ 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\n", - kobject_name(kobj), kobj, __func__); + 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() " @@ -580,9 +613,25 @@ static void kobject_cleanup(struct kobject *kobj) } } +#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) { - kobject_cleanup(container_of(kref, struct kobject, kref)); + struct kobject *kobj = container_of(kref, struct kobject, kref); +#ifdef CONFIG_DEBUG_KOBJECT_RELEASE + pr_info("kobject: '%s' (%p): %s, parent %p (delayed)\n", + kobject_name(kobj), kobj, __func__, kobj->parent); + INIT_DELAYED_WORK(&kobj->release, kobject_delayed_cleanup); + schedule_delayed_work(&kobj->release, HZ); +#else + kobject_cleanup(kobj); +#endif } /** @@ -711,6 +760,55 @@ const struct sysfs_ops kobj_sysfs_ops = { }; /** + * kobj_completion_init - initialize a kobj_completion object. + * @kc: kobj_completion + * @ktype: type of kobject to initialize + * + * kobj_completion structures can be embedded within structures with different + * lifetime rules. During the release of the enclosing object, we can + * wait on the release of the kobject so that we don't free it while it's + * still busy. + */ +void kobj_completion_init(struct kobj_completion *kc, struct kobj_type *ktype) +{ + init_completion(&kc->kc_unregister); + kobject_init(&kc->kc_kobj, ktype); +} +EXPORT_SYMBOL_GPL(kobj_completion_init); + +/** + * kobj_completion_release - release a kobj_completion object + * @kobj: kobject embedded in kobj_completion + * + * Used with kobject_release to notify waiters that the kobject has been + * released. + */ +void kobj_completion_release(struct kobject *kobj) +{ + struct kobj_completion *kc = kobj_to_kobj_completion(kobj); + complete(&kc->kc_unregister); +} +EXPORT_SYMBOL_GPL(kobj_completion_release); + +/** + * kobj_completion_del_and_wait - release the kobject and wait for it + * @kc: kobj_completion object to release + * + * Delete the kobject from sysfs and drop the reference count. Then wait + * until any other outstanding references are also dropped. This routine + * is only necessary once other references may have been taken on the + * kobject. Typically this happens when the kobject has been published + * to sysfs via kobject_add. + */ +void kobj_completion_del_and_wait(struct kobj_completion *kc) +{ + kobject_del(&kc->kc_kobj); + kobject_put(&kc->kc_kobj); + wait_for_completion(&kc->kc_unregister); +} +EXPORT_SYMBOL_GPL(kobj_completion_del_and_wait); + +/** * kset_register - initialize and add a kset. * @k: kset. */ @@ -915,6 +1013,18 @@ 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) { |