2 files changed, 15 insertions, 20 deletions

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 <linux/sched.h>
 #include <linux/fs.h>
 #include <linux/namei.h>
 #include <linux/idr.h>
@@ -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 <linux/lockdep.h>
 #include <linux/rbtree.h>
 #include <linux/atomic.h>
-#include <linux/completion.h>
+#include <linux/wait.h>
 
 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 {