PCI Configuration read from NVMe Miniport driver in Windows 7 VM - Hyper-V

Hi,

We have developed a Storport based NVMe Miniport driver for our Qualification tool in Windows 7 desktop environment.
Driver reads first 512 bytes of PCI Configuration space registers for a custom feature. We are using StorPortGetBusData
function for this purpose.

This works well in Windows 7 Desktop environment.

We installed the same driver on Windows 7 Virtual Machine with Hyper-V and exposed NVMe SSD as Virtual Function to Windows 7 VM.But in Windows 7 VM, StorportGetBusData is returning valid values for first 256 bytes and zeros for remaining 256 bytes of data. Also we tried with IobuildSynchronousFSdRequest (with  PCI_WHICHSPCE_CONFIG). but same behavior is observed.

Kindly let me know whether there is any other API/method to read first 512 bytes of PCI Configuration space registers. 
Also please let me know whether there is any other configuration do we need to change in Hyper-V?

Thanks & Regards,
Raphel