USER MODE DEVICE DRIVER INTERFACE

• US 20020152331A1
• Filed: 12/15/1998
• Published: 10/17/2002
• Est. Priority Date: 12/15/1998
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: WANG, LINGYUN, WONG, GILMAN K., OLYNYK, KIRK O., XU, DAVID LIPING, GOOSSEN, JAMES ANDREW ALAN, LEE, HOCK S.
• Granted Patent: US 6,871,350 B2
• Time in Patent Office: Days
• US Class Current: 719/321
• CPC Class Codes: H04L 69/32 Architecture of open systems interconnection [OSI] 7-layer type protocol stacks, e.g. the interfaces between the data link level and the physical level
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A user mode device driver interface (UMDDI) is disclosed. The UMDDI is preferably implemented in Windows® NT® version 5.0 and similar systems. The UMDDI allows a device driver to execute in user-mode while the graphics engine (GRE) remains in kernel-mode. The UMDDI exists as a layer between the user-mode driver and GRE; from the perspective of GRE, it encapsulates the user-mode driver and makes it appear to be a normal kernel-mode driver. The UMDDI layer handles the kernel-to-user and user-to-kernel transitions, parameter validation, and management of the kernel-mode and user-mode data and objects.

Claims

1. A method for operating a computer system, comprising:

executing a graphics engine in a kernel mode of operation;

executing a device driver in a user mode of operation, wherein the device driver communicates with the graphics engine executing in kernel mode.

2. A method according to claim 1 further wherein the device driver appears to operate, from the perspective of the graphics engine, as if it were a kernel mode driver.

3. A method according to claim 2 further wherein the device driver is made to appear as though it were operating in kernel mode by providing an interface between the graphics engine and the device driver.

4. A method according to claim 3 further wherein the interface translates kernel mode calls from the graphics engine to calls executable in user mode by the device driver, and translates user mode calls from the device driver to calls executable in kernel mode by the graphics engine.

5. A method according to claim 4 wherein the interface supplies copies of kernel mode objects to the user mode for use in executing user mode functions.

6. A method according to claim 5 wherein the interface provides copies of user mode objects to the kernel mode for use in executing kernel mode functions.

7. An article of manufacture comprising a computer readable medium encoded with an interface computer program executable on a suitably configured computer to provide communications between a graphics engine executing in a kernel mode of an operating system and a user mode device driver executing in a user mode of the operating system.

8. An article of manufacture according to claim 7 further wherein the interface program provides that the device driver is made to appear as though it were operating like a kernel mode driver.

9. An article of manufacture according to claim 7 further wherein the interface program provides translation of kernel mode calls from the graphics engine to calls executable in user mode by the device driver, and translation of user mode calls from the device driver to calls executable in kernel mode by the graphics engine.

10. An article of manufacture according to claim 7 further wherein the interface program supplies copies of kernel mode objects to the user mode for use in executing user mode functions.

11. An article of manufacture according to claim 10 further wherein the interface program provides copies of user mode objects to the kernel mode for use in executing kernel mode functions.

13. A computer system according to claim 12 further wherein the device driver operates, from the perspective of the graphics engine, as if it were a kernel mode driver.

14. A computer system according to claim 13 further including an interface executing in both the kernel mode and the user mode to provide communication between the graphics engine and the device driver and to make the device driver appear as though it were operating in kernel mode.

15. A computer system according to claim 14 further wherein the interface translates kernel mode calls from the graphics engine to calls executable in user mode by the device driver, and translates user mode calls from the device driver to calls executable in kernel mode by the graphics engine.

16. A computer system according to claim 14 wherein the interface supplies copies of kernel mode objects to the user mode for use in executing user mode functions.

17. A computer system according to claim 16 wherein the interface provides copies of user mode objects to the kernel mode for use in executing kernel mode functions.

19. An operating system according to claim 18 further wherein the interface program operates to make the device driver appear as though it were operating in the kernel mode.

20. An operating system according to claim 18 further wherein the interface program translates kernel mode calls from the graphics engine to calls executable in user mode by the user mode driver, and translates user mode calls from the user mode driver to calls executable in kernel mode by the graphics engine.

21. An operating system according to claim 18 wherein the interface program supplies copies of kernel mode objects to the user mode for use in executing user mode functions.

22. An operating system according to claim 18 wherein the interface program provides copies of user mode objects to the kernel mode for use in executing kernel mode functions.

12. A computer system comprising:

a graphics engine executing in a kernel mode of an operating system; and

a device driver executing in a user mode of an operating system and communicates with the graphics engine.

18. An operating system computer program encoded in a machine readable medium and including a graphics engine executable in a kernel mode of the operating system, a device driver executable in a user mode of the operating system, and an interface program executable in both the kernel mode and the user mode, the interface program coupled between the graphics engine and the device driver.