IOCTL_MOUNTDEV_QUERY_DEVICE_NAME - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTIOAPI_H

#define IOCTL_MOUNTDEV_QUERY_DEVICE_NAME            CTL_CODE(MOUNTDEVCONTROLTYPE, 2, METHOD_BUFFERED, FILE_ANY_ACCESS)

#endif

View code on GitHub

This IOCTL is documented in Windows Driver Kit.