diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst
index d3a93eec3945..de8f8502056e 100644
--- a/Documentation/filesystems/vfs.rst
+++ b/Documentation/filesystems/vfs.rst
@@ -507,8 +507,8 @@ otherwise noted.
 	dentry before the first mkdir returns.
 
 	If there is any chance this could happen, then the new inode
-	should be d_drop()ed and attached with d_splice_alias().  The
-	returned dentry (if any) should be returned by ->mkdir().
+	should be attached with d_splice_alias().  The returned
+	dentry (if any) should be returned by ->mkdir().
 
 ``rmdir``
 	called by the rmdir(2) system call.  Only required if you want
diff --git a/fs/dcache.c b/fs/dcache.c
index 1b1a81f10da6..fd74753e7715 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -2168,7 +2168,6 @@ static void __d_instantiate(struct dentry *dentry, struct inode *inode)
  * (or otherwise set) by the caller to indicate that it is now
  * in use by the dcache.
  */
- 
 void d_instantiate(struct dentry *entry, struct inode * inode)
 {
 	BUG_ON(d_really_is_positive(entry));
@@ -2931,15 +2930,10 @@ static inline void __d_add(struct dentry *dentry, struct inode *inode,
 	}
 	if (unlikely(ops))
 		d_set_d_op(dentry, ops);
-	if (inode) {
-		unsigned add_flags = d_flags_for_inode(inode);
-		hlist_add_head(&dentry->d_alias, &inode->i_dentry);
-		raw_write_seqcount_begin(&dentry->d_seq);
-		__d_set_inode_and_type(dentry, inode, add_flags);
-		raw_write_seqcount_end(&dentry->d_seq);
-		fsnotify_update_flags(dentry);
-	}
-	__d_rehash(dentry);
+	if (inode)
+		__d_instantiate(dentry, inode);
+	if (d_unhashed(dentry))
+		__d_rehash(dentry);
 	if (dir) {
 		end_dir_add(dir, n);
 		__d_wake_in_lookup_waiters(dentry);
@@ -3241,7 +3235,7 @@ struct dentry *d_splice_alias_ops(struct inode *inode, struct dentry *dentry,
 	if (IS_ERR(inode))
 		return ERR_CAST(inode);
 
-	BUG_ON(!d_unhashed(dentry));
+	BUG_ON(d_really_is_positive(dentry));
 
 	if (!inode)
 		goto out;
@@ -3297,6 +3291,8 @@ struct dentry *d_splice_alias_ops(struct inode *inode, struct dentry *dentry,
  * @inode:  the inode which may have a disconnected dentry
  * @dentry: a negative dentry which we want to point to the inode.
  *
+ * @dentry must be negative and may be in-lookup or unhashed or hashed.
+ *
  * If inode is a directory and has an IS_ROOT alias, then d_move that in
  * place of the given dentry and return it, else simply d_add the inode
  * to the dentry and return NULL.
@@ -3304,16 +3300,14 @@ struct dentry *d_splice_alias_ops(struct inode *inode, struct dentry *dentry,
  * If a non-IS_ROOT directory is found, the filesystem is corrupt, and
  * we should error out: directories can't have multiple aliases.
  *
- * This is needed in the lookup routine of any filesystem that is exportable
- * (via knfsd) so that we can build dcache paths to directories effectively.
+ * This should be used to return the result of ->lookup() and to
+ * instantiate the result of ->mkdir(), is often useful for
+ * ->atomic_open, and may be used to instantiate other objects.
  *
  * If a dentry was found and moved, then it is returned.  Otherwise NULL
- * is returned.  This matches the expected return value of ->lookup.
+ * is returned.  This matches the expected return value of ->lookup and
+ * ->mkdir.
  *
- * Cluster filesystems may call this function with a negative, hashed dentry.
- * In that case, we know that the inode will be a regular file, and also this
- * will only occur during atomic_open. So we need to check for the dentry
- * being already hashed only in the final case.
  */
 struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry)
 {