host_inode = host_dentry->d_inode;
mutex_lock(&host_inode->i_mutex);
err = host_file->f_op->fsync(host_file, host_dentry, datasync);
host_inode = host_dentry->d_inode;
mutex_lock(&host_inode->i_mutex);
err = host_file->f_op->fsync(host_file, host_dentry, datasync);