diff options
Diffstat (limited to 'lib')
-rw-r--r-- | lib/Kconfig.debug | 2 | ||||
-rw-r--r-- | lib/kobject.c | 95 | ||||
-rw-r--r-- | lib/percpu-refcount.c | 3 | ||||
-rw-r--r-- | lib/scatterlist.c | 3 |
4 files changed, 96 insertions, 7 deletions
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 2932937..ebef88f 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -992,7 +992,7 @@ config DEBUG_KOBJECT config DEBUG_KOBJECT_RELEASE bool "kobject release debugging" - depends on DEBUG_KERNEL + depends on DEBUG_OBJECTS_TIMERS help kobjects are reference counted objects. This means that their last reference count put is not predictable, and the kobject can diff --git a/lib/kobject.c b/lib/kobject.c index 669bf19..7a1c203 100644 --- a/lib/kobject.c +++ b/lib/kobject.c @@ -13,11 +13,33 @@ */ #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); + const void *ns; + + if (!ns_ops || ns_ops->type == KOBJ_NS_TYPE_NONE) + return NULL; + + ns = kobj->ktype->namespace(kobj); + WARN_ON(!ns); /* @kobj in a namespace is required to have !NULL tag */ + return ns; +} + /* * populate_dir - populate directory with attributes. * @kobj: object we're working on. @@ -46,13 +68,21 @@ 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 +458,7 @@ 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 +502,7 @@ 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 +517,7 @@ 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 +539,15 @@ 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); @@ -592,7 +628,7 @@ static void kobject_release(struct kref *kref) { struct kobject *kobj = container_of(kref, struct kobject, kref); #ifdef CONFIG_DEBUG_KOBJECT_RELEASE - pr_debug("kobject: '%s' (%p): %s, parent %p (delayed)\n", + 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); @@ -727,6 +763,55 @@ 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. */ diff --git a/lib/percpu-refcount.c b/lib/percpu-refcount.c index 7deeb62..1a53d49 100644 --- a/lib/percpu-refcount.c +++ b/lib/percpu-refcount.c @@ -53,6 +53,7 @@ int percpu_ref_init(struct percpu_ref *ref, percpu_ref_func_t *release) ref->release = release; return 0; } +EXPORT_SYMBOL_GPL(percpu_ref_init); /** * percpu_ref_cancel_init - cancel percpu_ref_init() @@ -84,6 +85,7 @@ void percpu_ref_cancel_init(struct percpu_ref *ref) free_percpu(ref->pcpu_count); } } +EXPORT_SYMBOL_GPL(percpu_ref_cancel_init); static void percpu_ref_kill_rcu(struct rcu_head *rcu) { @@ -156,3 +158,4 @@ void percpu_ref_kill_and_confirm(struct percpu_ref *ref, call_rcu_sched(&ref->rcu, percpu_ref_kill_rcu); } +EXPORT_SYMBOL_GPL(percpu_ref_kill_and_confirm); diff --git a/lib/scatterlist.c b/lib/scatterlist.c index a685c8a..d16fa29 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -577,7 +577,8 @@ void sg_miter_stop(struct sg_mapping_iter *miter) miter->__offset += miter->consumed; miter->__remaining -= miter->consumed; - if (miter->__flags & SG_MITER_TO_SG) + if ((miter->__flags & SG_MITER_TO_SG) && + !PageSlab(miter->page)) flush_kernel_dcache_page(miter->page); if (miter->__flags & SG_MITER_ATOMIC) { |