Isolation of user-mode device drivers

• US 20060242270A1
• Filed: 04/21/2005
• Published: 10/26/2006
• Est. Priority Date: 04/21/2005
• Status: Abandoned Application

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Sankaranarayan, Mukund, Patrick, Stuart R., Dai, Chung Lang
• Application Number:
  US11/111,016
• Publication Number:
  US 20060242270A1
• Time in Patent Office: Days
• US Class Current: 709/220
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers

Abstract

A host process for use in a user-mode device driver architecture is provided by the subject invention. The architecture includes a reflector, a driver manager and the host process which hosts and isolates one or more user-mode device driver(s). The user-mode device driver runs in the user-mode (UM) environment and has access to various UM services. The reflector resides in “kernel memory” (e.g., memory/resource(s) available to operating system) while the driver manager, host process and user mode device driver(s) are located in user space (e.g., memory/resource(s) available to user application(s)). The host process can include a host runtime component and a framework component. The host runtime component is responsible for building a driver stack object, and, locating/loading object(s) of a framework component. The host runtime component further includes a message handler that facilitates communication with the reflector and routes information to components of the host process.

Claims

1. A host process component of a user-mode device driver architecture comprising:

a message handler that receives a message from a reflector in kernel mode, generates a user mode IRP comprising the message, and, stores the user mode IRP in a user mode IRP store; and

,

a device stack object that identifies a user-mode device driver associated with a device, constructs a device stack associated with the device, and, instantiates framework objects associated with the device stack, the framework objects facilitates communication with the user mode device driver.

2. The host process component of claim 1, the message exchanged between the reflector and the message handler comprising an ALPC message.

3. The host process component of claim 1, the message associated with a corresponding I/O request from an application.

4. The host process component of claim 1, the reflector and message handler communicate via a plurality of channels.

5. The host process component of claim 1, the framework objects raise events to the user-mode device drivers.

6. The host process component of claim 1, the framework objects comprising a queue object that facilitates communication between the host process and the user-mode device driver.

7. The host process component of claim 6, the queue object employs a sequential dispatch mode.

8. The host process component of claim 6, the queue object employs a parallel dispatch mode.

9. The host process component of claim 6, the queue object employs an upon request from the user-mode device driver dispatch mode.

10. The host process component of claim 6, the queue object created in response to a request from the user-mode device driver.

11. The host process component of claim 1, the framework objects comprising a device object exposed to the user-mode device driver, the device object is a runtime representation of a device.

12. The host process component of claim 11, the user-mode device driver registers with the device object to receive notifications.

13. The host process component of claim 1, the framework objects comprising a driver object exposed to the user-mode device driver, the driver object is a runtime representation of the user-mode device driver in the host process component.

14. The host process component of claim 1, the framework objects comprising a base object exposed to the user-mode device driver, the base object provides basic functionality common across a plurality of framework objects.

15. The host process component of claim 1, the framework objects comprising a file object exposed to the user-mode device driver, the file object is a runtime representation of an opened device.

16. The host process component of claim 1, the framework objects comprising a request object which encapsulates details of an I/O operation.

17. A method of adding a device in a user-mode device driver architecture comprising:

building a user mode IRP based on a request to add a device;

inserting the user mode IRP into a user mode IRP store;

identifying drivers associated with the user mode IRP;

constructing a device stack associated with the driver identified;

instantiating framework objects associated with the device stack; and

,

initializing the identified drivers.

18. The method of claim 17, further comprising at least one of:

providing a user mode IRP reply; and

,

providing a reply to an initiator of the add device request.

19. A computer readable medium having stored thereon computer executable instructions for carrying out the method of claim 17.

20. A data packet transmitted between two or more computer components that facilitates communication between a host process and a user-mode device driver, the data packet comprising:

a user mode IRP corresponding to an I/O request from an application, the user mode IRP message generated by the host process in user mode.