#ifndef _NTIOAPI_H
// Input structure for IOCTL_MOUNTMGR_VOLUME_MOUNT_POINT_CREATED and
// IOCTL_MOUNTMGR_VOLUME_MOUNT_POINT_DELETED.
typedef struct _MOUNTMGR_VOLUME_MOUNT_POINT
{
USHORT SourceVolumeNameOffset;
USHORT SourceVolumeNameLength;
USHORT TargetVolumeNameOffset;
USHORT TargetVolumeNameLength;
} MOUNTMGR_VOLUME_MOUNT_POINT, *PMOUNTMGR_VOLUME_MOUNT_POINT;
View code on GitHub
This structure is documented in Windows Driver Kit.