+ssize_t __vfs_read(struct file *file, char __user *buf, size_t count,
+ loff_t *pos)
+{
+ ssize_t ret;
+
+ if (file->f_op->read)
+ ret = file->f_op->read(file, buf, count, pos);
+ else if (file->f_op->aio_read)
+ ret = do_sync_read(file, buf, count, pos);
+ else if (file->f_op->read_iter)
+ ret = new_sync_read(file, buf, count, pos);
+ else
+ ret = -EINVAL;
+
+ return ret;
+}
+