1 files changed, 28 insertions, 7 deletions

diff --git a/fs/dcache.c b/fs/dcache.c
index 71969505e82e..b6cdc0ffca6f 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2712,32 +2712,51 @@ mismatch:
 }
 EXPORT_SYMBOL(d_alloc_parallel);
 
-void __d_lookup_done(struct dentry *dentry)
+/*
+ * - Unhash the dentry
+ * - Retrieve and clear the waitqueue head in dentry
+ * - Return the waitqueue head
+ */
+static wait_queue_head_t *__d_lookup_unhash(struct dentry *dentry)
 {
-	struct hlist_bl_head *b = in_lookup_hash(dentry->d_parent,
-						 dentry->d_name.hash);
+	wait_queue_head_t *d_wait;
+	struct hlist_bl_head *b;
+
+	lockdep_assert_held(&dentry->d_lock);
+
+	b = in_lookup_hash(dentry->d_parent, dentry->d_name.hash);
 	hlist_bl_lock(b);
 	dentry->d_flags &= ~DCACHE_PAR_LOOKUP;
 	__hlist_bl_del(&dentry->d_u.d_in_lookup_hash);
-	wake_up_all(dentry->d_wait);
+	d_wait = dentry->d_wait;
 	dentry->d_wait = NULL;
 	hlist_bl_unlock(b);
 	INIT_HLIST_NODE(&dentry->d_u.d_alias);
 	INIT_LIST_HEAD(&dentry->d_lru);
+	return d_wait;
+}
+
+void __d_lookup_unhash_wake(struct dentry *dentry)
+{
+	spin_lock(&dentry->d_lock);
+	wake_up_all(__d_lookup_unhash(dentry));
+	spin_unlock(&dentry->d_lock);
 }
-EXPORT_SYMBOL(__d_lookup_done);
+EXPORT_SYMBOL(__d_lookup_unhash_wake);
 
 /* inode->i_lock held if inode is non-NULL */
 
 static inline void __d_add(struct dentry *dentry, struct inode *inode)
 {
+	wait_queue_head_t *d_wait;
 	struct inode *dir = NULL;
 	unsigned n;
 	spin_lock(&dentry->d_lock);
 	if (unlikely(d_in_lookup(dentry))) {
 		dir = dentry->d_parent->d_inode;
 		n = start_dir_add(dir);
-		__d_lookup_done(dentry);
+		d_wait = __d_lookup_unhash(dentry);
+		wake_up_all(d_wait);
 	}
 	if (inode) {
 		unsigned add_flags = d_flags_for_inode(inode);
@@ -2896,6 +2915,7 @@ static void __d_move(struct dentry *dentry, struct dentry *target,
 		     bool exchange)
 {
 	struct dentry *old_parent, *p;
+	wait_queue_head_t *d_wait;
 	struct inode *dir = NULL;
 	unsigned n;
 
@@ -2926,7 +2946,8 @@ static void __d_move(struct dentry *dentry, struct dentry *target,
 	if (unlikely(d_in_lookup(target))) {
 		dir = target->d_parent->d_inode;
 		n = start_dir_add(dir);
-		__d_lookup_done(target);
+		d_wait = __d_lookup_unhash(target);
+		wake_up_all(d_wait);
 	}
 
 	write_seqcount_begin(&dentry->d_seq);