Identifying and correlating physical devices across disconnected device stacks

1. A method, comprising:

determining, by a driver at a file system layer in a storage functional path associated with a mass storage device connected to a computing device, a volume Physical Device Object (PDO) identifier used at a volume layer of the storage functional path;

determining, by the driver, a device number associated with the volume PDO identifier;

determining, by the driver, a disk PDO identifier used at a disk layer of the storage functional path that is also associated with the device number;

obtaining, by the driver, a parent device instance identifier associated with the disk PDO identifier;

mapping, by the driver, a file system identifier for the mass storage device used by the driver in the storage functional path to the parent device instance identifier; and

using, by the driver, the parent device instance identifier as a plug-and-play (PnP) identifier for the mass storage device during communications with a second driver in a PnP functional path.

2. The method of claim 1 , wherein obtaining the parent device instance identifier associated with the disk PDO identifier comprises using an operating system routine to directly retrieve the parent device instance identifier based on the disk PDO identifier.

3. The method of claim 1 , wherein the mass storage device is a Universal Serial Bus (USB) device and wherein obtaining the parent device instance identifier associated with the disk PDO identifier comprises:

retrieving, by the driver, a device instance identifier associated with the disk PDO identifier;

identifying, by the driver, the mass storage device among one or more enumerated USB devices connected to the computing device based on the mass storage device also being associated with the device instance identifier; and

using, by the driver, a USB device PDO identifier associated with the mass storage device as the parent device instance identifier.

4. The method of claim 3 , wherein the device instance identifier is an identifier assigned to the mass storage device in the PnP functional path.

5. The method of claim 1 , wherein the driver is a device control file system minifilter configured to selectively block individual read or write requests associated with the mass storage device based on information about a blocking policy retrieved from the second driver in response to the communications.

6. The method of claim 5 , wherein the blocking policy identifies the mass storage device based on the PnP identifier.

7. The method of claim 5 , wherein the second driver is a device control PnP driver configured to selectively block the mass storage device from being mounted at system boot or when the mass storage device is plugged in to the computing device based on the blocking policy.

8. The method of claim 1 , wherein the mass storage device is a Universal Serial Bus (USB) device.

9. A method, comprising:

determining, by a driver at a first layer of a functional path associated with a hardware device connected to a computing device, a first Physical Device Object (PDO) identifier used at a second layer of the functional path;

determining, by the driver, a device number associated with the first PDO identifier;

determining, by the driver, a second PDO identifier at a third layer of the functional path that is also associated with the device number;

obtaining, by the driver, a parent device instance identifier associated with the second PDO identifier;

mapping, by the driver, a first identifier for the hardware device used by the driver in the functional path to the parent device instance identifier; and

using, by the driver, the parent device instance identifier as a second identifier for the hardware device during communications with a second driver in a different functional path.

10. The method of claim 9 , wherein obtaining the parent device instance identifier associated with the second PDO identifier comprises using an operating system routine to directly retrieve the parent device instance identifier based on the second PDO identifier.

11. The method of claim 9 , wherein the hardware device is a Universal Serial Bus (USB) device and wherein obtaining the parent device instance identifier associated with the second PDO identifier comprises:

retrieving, by the driver, a device instance identifier associated with the second PDO identifier;

identifying, by the driver, the hardware device among one or more enumerated USB devices connected to the computing device based on the hardware device also being associated with the device instance identifier; and

using, by the driver, a USB device PDO identifier associated with the hardware device as the parent device instance identifier.

12. The method of claim 11 , wherein the device instance identifier is an identifier assigned to the hardware device in the different functional path.

13. The method of claim 9 , wherein the functional path is a storage functional path and the different functional path is a Plug-and-Play (PnP) functional path.

14. The method of claim 9 , wherein the functional path is a networking functional path and the different functional path is a Plug-and-Play (PnP) functional path.

15. One or more non-transitory computer-readable media storing computer-executable instructions for a driver that, when executed by one or more processors of a computing device, cause the one or more processors to perform operations comprising:

determining, at a file system layer in a storage functional path associated with a mass storage device connected to the computing device, a volume Physical Device Object (PDO) identifier used at a volume layer of the storage functional path;

determining a device number associated with the volume PDO identifier;

determining a disk PDO identifier used at a disk layer of the storage functional path that is also associated with the device number;

obtaining a parent device instance identifier associated with the disk PDO identifier;

mapping a file system identifier for the mass storage device used at the file system layer in the storage functional path to the parent device instance identifier; and

using the parent device instance identifier as a plug-and-play (PnP) identifier for the mass storage device during communications between the driver at the file system layer and a second driver in a PnP functional path.

16. The non-transitory computer-readable media of claim 15 , wherein obtaining the parent device instance identifier associated with the disk PDO identifier comprises using an operating system routine to directly retrieve the parent device instance identifier based on the disk PDO identifier.

17. The non-transitory computer-readable media of claim 15 , wherein the mass storage device is a Universal Serial Bus (USB) device and wherein obtaining the parent device instance identifier associated with the disk PDO identifier comprises:

retrieving a device instance identifier associated with the disk PDO identifier;

identifying the mass storage device among one or more enumerated USB devices connected to the computing device based on the mass storage device also being associated with the device instance identifier; and

using a USB device PDO identifier associated with the mass storage device as the parent device instance identifier.

18. The non-transitory computer-readable media of claim 15 , wherein the driver is a device control file system minifilter configured to selectively block individual read or write requests associated with the mass storage device based on information about a blocking policy retrieved from the second driver in response to the communications.

19. The non-transitory computer-readable media of claim 18 , wherein the blocking policy identifies the mass storage device based on the PnP identifier.

20. The non-transitory computer-readable media of claim 18 , wherein the second driver is a device control PnP driver configured to selectively block the mass storage device from being mounted at system boot or when the mass storage device is plugged in to the computing device based on the blocking policy.