diff options
Diffstat (limited to 'lib/kobject.c')
| -rw-r--r-- | lib/kobject.c | 143 |
1 files changed, 116 insertions, 27 deletions
diff --git a/lib/kobject.c b/lib/kobject.c index c33d7a18d63..58751bb80a7 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -14,9 +14,28 @@ #include <linux/kobject.h> #include <linux/string.h> -#include <linux/module.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. @@ -46,16 +65,39 @@ static int populate_dir(struct kobject *kobj) static int create_dir(struct kobject *kobj) { - int error = 0; - if (kobject_name(kobj)) { - error = sysfs_create_dir(kobj); - if (!error) { - error = populate_dir(kobj); - if (error) - sysfs_remove_dir(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; } - 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) @@ -192,14 +234,14 @@ static int kobject_add_internal(struct kobject *kobj) /* be noisy on error issues */ if (error == -EEXIST) - printk(KERN_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)); + WARN(1, "%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 - printk(KERN_ERR "%s failed for %s (%d)\n", - __func__, kobject_name(kobj), error); - dump_stack(); + WARN(1, "%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; @@ -222,8 +264,10 @@ int kobject_set_name_vargs(struct kobject *kobj, const char *fmt, return 0; kobj->name = kvasprintf(GFP_KERNEL, fmt, vargs); - if (!kobj->name) + if (!kobj->name) { + kobj->name = old_name; return -ENOMEM; + } /* ewww... some of these buggers have '/' in the name ... */ while ((s = strchr(kobj->name, '/'))) @@ -321,7 +365,7 @@ static int kobject_add_varg(struct kobject *kobj, struct kobject *parent, * * 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 associted with the kset assigned to this kobject. If no kset + * 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. * @@ -430,7 +474,7 @@ 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; @@ -474,6 +518,7 @@ 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) { @@ -488,7 +533,7 @@ 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; @@ -510,10 +555,15 @@ out: */ 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); @@ -531,6 +581,13 @@ struct kobject *kobject_get(struct kobject *kobj) return kobj; } +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 @@ -540,8 +597,8 @@ 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() " @@ -575,9 +632,27 @@ 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 + 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 } /** @@ -634,7 +709,7 @@ struct kobject *kobject_create(void) /** * kobject_create_and_add - create a struct kobject dynamically and register it with sysfs * - * @name: the name for the kset + * @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 @@ -704,6 +779,7 @@ 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. @@ -732,6 +808,7 @@ void kset_unregister(struct kset *k) { if (!k) return; + kobject_del(&k->kobj); kobject_put(&k->kobj); } @@ -753,7 +830,7 @@ struct kobject *kset_find_obj(struct kset *kset, const char *name) list_for_each_entry(k, &kset->list, entry) { if (kobject_name(k) && !strcmp(kobject_name(k), name)) { - ret = kobject_get(k); + ret = kobject_get_unless_zero(k); break; } } @@ -800,7 +877,7 @@ static struct kset *kset_create(const char *name, kset = kzalloc(sizeof(*kset), GFP_KERNEL); if (!kset) return NULL; - retval = kobject_set_name(&kset->kobj, name); + retval = kobject_set_name(&kset->kobj, "%s", name); if (retval) { kfree(kset); return NULL; @@ -910,6 +987,18 @@ 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) { |