Drive letter for a GPT partition (custom GUID) RRS feed

  • Question

  • Hi,

    I am trying to write a driver to generate a drive letter for a custom GPT partition type. From the documentation, it appears that a drive letter can only be generated for a PARTITION_BASIC_DATA_GUID Partition Type.

    I wrote a class filter driver for the Disk class that intercepts the IOCTL_DISK_GET_DRIVE_LAYOUT_INFORMATION_EX and then changes the Partition Type from my custom GUID to the PARTITION_BASIC_DATA_GUID value in the completion routine but I still do not get a drive letter.

    I have read the "Supporting Mount Manager Requests in a Storage Class Driver" about calling IoRegisterDeviceInterface with the MOUNTDEV_MOUNTED_DEVICE_GUID but I have a few questions:

    1. Am I on the right path? Should I be writing a upper class filter for the Volume class to intercept the creation of the /Device/HarddiskVolume%d PDO and then send the mountmgr request there?

    2. In my current Disk class filter driver, how do I query the system object Device tree for the existing "/Device/HarddiskVolume%d" PDO's so I can use it in my mount mgr IOCTLs?



    Friday, March 27, 2015 3:01 PM