diff --git a/fs/kernfs/dir.c b/fs/kernfs/dir.c index bd6e18be6e1a..2193d30156ef 100644 --- a/fs/kernfs/dir.c +++ b/fs/kernfs/dir.c @@ -8,6 +8,7 @@ * This file is released under the GPLv2. */ +#include #include #include #include @@ -151,6 +152,7 @@ struct kernfs_node *kernfs_get_active(struct kernfs_node *kn) */ void kernfs_put_active(struct kernfs_node *kn) { + struct kernfs_root *root = kernfs_root(kn); int v; if (unlikely(!kn)) @@ -162,11 +164,7 @@ void kernfs_put_active(struct kernfs_node *kn) if (likely(v != KN_DEACTIVATED_BIAS)) return; - /* - * atomic_dec_return() is a mb(), we'll always see the updated - * kn->u.completion. - */ - complete(kn->u.completion); + wake_up_all(&root->deactivate_waitq); } /** @@ -177,28 +175,24 @@ void kernfs_put_active(struct kernfs_node *kn) */ static void kernfs_deactivate(struct kernfs_node *kn) { - DECLARE_COMPLETION_ONSTACK(wait); - int v; + struct kernfs_root *root = kernfs_root(kn); BUG_ON(!(kn->flags & KERNFS_REMOVED)); if (!(kernfs_type(kn) & KERNFS_ACTIVE_REF)) return; - kn->u.completion = (void *)&wait; - if (kn->flags & KERNFS_LOCKDEP) rwsem_acquire(&kn->dep_map, 0, 0, _RET_IP_); - /* atomic_add_return() is a mb(), put_active() will always see - * the updated kn->u.completion. - */ - v = atomic_add_return(KN_DEACTIVATED_BIAS, &kn->active); - if (v != KN_DEACTIVATED_BIAS) { - if (kn->flags & KERNFS_LOCKDEP) - lock_contended(&kn->dep_map, _RET_IP_); - wait_for_completion(&wait); - } + atomic_add(KN_DEACTIVATED_BIAS, &kn->active); + + if ((kn->flags & KERNFS_LOCKDEP) && + atomic_read(&kn->active) != KN_DEACTIVATED_BIAS) + lock_contended(&kn->dep_map, _RET_IP_); + + wait_event(root->deactivate_waitq, + atomic_read(&kn->active) == KN_DEACTIVATED_BIAS); if (kn->flags & KERNFS_LOCKDEP) { lock_acquired(&kn->dep_map, _RET_IP_); @@ -630,6 +624,7 @@ struct kernfs_root *kernfs_create_root(struct kernfs_dir_ops *kdops, void *priv) root->dir_ops = kdops; root->kn = kn; + init_waitqueue_head(&root->deactivate_waitq); return root; } diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h index 5be9f0228a3b..295a3bf642ba 100644 --- a/include/linux/kernfs.h +++ b/include/linux/kernfs.h @@ -15,7 +15,7 @@ #include #include #include -#include +#include struct file; struct dentry; @@ -92,7 +92,6 @@ struct kernfs_node { struct rb_node rb; union { - struct completion *completion; struct kernfs_node *removed_list; } u; @@ -133,6 +132,7 @@ struct kernfs_root { /* private fields, do not use outside kernfs proper */ struct ida ino_ida; struct kernfs_dir_ops *dir_ops; + wait_queue_head_t deactivate_waitq; }; struct kernfs_open_file {