--- zzzz-none-000/linux-3.10.107/arch/s390/hypfs/hypfs_dbfs.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/s390/hypfs/hypfs_dbfs.c	2021-02-04 17:41:59.000000000 +0000
@@ -17,33 +17,16 @@
 	data = kmalloc(sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return NULL;
-	kref_init(&data->kref);
 	data->dbfs_file = f;
 	return data;
 }
 
-static void hypfs_dbfs_data_free(struct kref *kref)
+static void hypfs_dbfs_data_free(struct hypfs_dbfs_data *data)
 {
-	struct hypfs_dbfs_data *data;
-
-	data = container_of(kref, struct hypfs_dbfs_data, kref);
 	data->dbfs_file->data_free(data->buf_free_ptr);
 	kfree(data);
 }
 
-static void data_free_delayed(struct work_struct *work)
-{
-	struct hypfs_dbfs_data *data;
-	struct hypfs_dbfs_file *df;
-
-	df = container_of(work, struct hypfs_dbfs_file, data_free_work.work);
-	mutex_lock(&df->lock);
-	data = df->data;
-	df->data = NULL;
-	mutex_unlock(&df->lock);
-	kref_put(&data->kref, hypfs_dbfs_data_free);
-}
-
 static ssize_t dbfs_read(struct file *file, char __user *buf,
 			 size_t size, loff_t *ppos)
 {
@@ -56,34 +39,42 @@
 
 	df = file_inode(file)->i_private;
 	mutex_lock(&df->lock);
-	if (!df->data) {
-		data = hypfs_dbfs_data_alloc(df);
-		if (!data) {
-			mutex_unlock(&df->lock);
-			return -ENOMEM;
-		}
-		rc = df->data_create(&data->buf, &data->buf_free_ptr,
-				     &data->size);
-		if (rc) {
-			mutex_unlock(&df->lock);
-			kfree(data);
-			return rc;
-		}
-		df->data = data;
-		schedule_delayed_work(&df->data_free_work, HZ);
+	data = hypfs_dbfs_data_alloc(df);
+	if (!data) {
+		mutex_unlock(&df->lock);
+		return -ENOMEM;
+	}
+	rc = df->data_create(&data->buf, &data->buf_free_ptr, &data->size);
+	if (rc) {
+		mutex_unlock(&df->lock);
+		kfree(data);
+		return rc;
 	}
-	data = df->data;
-	kref_get(&data->kref);
 	mutex_unlock(&df->lock);
 
 	rc = simple_read_from_buffer(buf, size, ppos, data->buf, data->size);
-	kref_put(&data->kref, hypfs_dbfs_data_free);
+	hypfs_dbfs_data_free(data);
+	return rc;
+}
+
+static long dbfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct hypfs_dbfs_file *df = file_inode(file)->i_private;
+	long rc;
+
+	mutex_lock(&df->lock);
+	if (df->unlocked_ioctl)
+		rc = df->unlocked_ioctl(file, cmd, arg);
+	else
+		rc = -ENOTTY;
+	mutex_unlock(&df->lock);
 	return rc;
 }
 
 static const struct file_operations dbfs_ops = {
 	.read		= dbfs_read,
 	.llseek		= no_llseek,
+	.unlocked_ioctl = dbfs_ioctl,
 };
 
 int hypfs_dbfs_create_file(struct hypfs_dbfs_file *df)
@@ -93,7 +84,6 @@
 	if (IS_ERR(df->dentry))
 		return PTR_ERR(df->dentry);
 	mutex_init(&df->lock);
-	INIT_DELAYED_WORK(&df->data_free_work, data_free_delayed);
 	return 0;
 }
 
@@ -105,7 +95,7 @@
 int hypfs_dbfs_init(void)
 {
 	dbfs_dir = debugfs_create_dir("s390_hypfs", NULL);
-	return PTR_RET(dbfs_dir);
+	return PTR_ERR_OR_ZERO(dbfs_dir);
 }
 
 void hypfs_dbfs_exit(void)