System for transferring I/O data between an I/O device and an application program's memory in accordance with a request directly over a virtual connection

• US 6,044,415 A
• Filed: 02/27/1998
• Issued: 03/28/2000
• Est. Priority Date: 02/27/1998
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Regnier, Greg J., Amway, Stanley S. III, Futral, William T.
• Primary Examiner(s): Lee, Thomas C.
• Assistant Examiner(s): Park, Ilwoo
• Application Number:
  US09/032,599
• Time in Patent Office: 760 Days
• Field of Search: 711/203, 709/301, 709/302, 709/229, 710/3, 710/4, 710/33, 710/37, 370/397, 370/399
• US Class Current: 710/33
• CPC Class Codes: G06F 9/455 Emulation; Interpretation; Software simulation, e.g. virtualisation or emulation of application or operating system execution engines

Abstract

A virtual connection created between an application program and a selected I/O device is used as a communications medium for controlling I/O processing of the I/O device by the application program. The virtual connection is implemented as a system area network connecting a process of the application program and the I/O device. The application program registers the application program'"'"'s memory that the application program shares with the I/O device (i.e., gives access rights to the I/O device) with the system area network. Once the virtual connection is created and initialized, the application program uses the virtual connection to send request messages for I/O services to the I/O device and to receive reply messages from the I/O device. The I/O device uses the virtual connection to obtain source data from the application program'"'"'s memory for I/O write operations and to transfer data to the application program'"'"'s memory for I/O read operations.

Claims

1. A method of controlling I/O operations of an I/O device by an application program comprising:

creating a virtual connection within a system area network between the application program and the I/O device, the application program and the I/O device being coupled to the system area network;

registering the application program'"'"'s memory with the system area network;

sending, by the application program, a request message for I/O service directly to the I/O device over the virtual connection, the request message including a virtual address of the application program'"'"'s memory; and

transferring I/O data between the I/O device and the application program'"'"'s memory specified by the virtual address over the virtual connection.

2. The method of claim 1, further comprising sending, by the I/O device, a reply message to the application program over the virtual connection after the transferring step.

3. The method of claim 1, wherein registering the application program'"'"'s memory with the system area network comprises providing access rights to the I/O device thereby allowing the I/O device to access the application program'"'"'s memory.

4. The method of claim 1, wherein the transferring step comprises transferring I/O data received by the I/O device to the application program'"'"'s memory when an I/O read operation is specified in the request message.

5. The method of claim 1, wherein the transferring step comprises transferring I/O data from the application program'"'"'s memory to the I/O device when an I/O write operation is specified in the request message.

6. The method of claim 1, wherein the application program is executed by a system having an operating system and the creating step comprises creating a connection between a network interface controller coupled to the system area network and a process of the application program, the connection not requiring performance of kernel services by the operating system.

7. The method of claim 1, wherein the request message further comprises a memory handle for protected access of the application program'"'"'s memory.

8. A system for controlling I/O operations of an I/O device by an application program comprising:

a system area network providing communications between the application program and the I/O device;

means for creating a virtual connection within the system area network between the application program and the I/O device;

means for registering the application program'"'"'s memory with the system area network;

means for sending, by the application program, a request message for I/O service directly to the I/O device over the virtual connection, the request message including a virtual address of the application program'"'"'s memory; and

means for transferring I/O data between the I/O device and the application program'"'"'s memory specified by the virtual address over the virtual connection.

9. The system of claim 8, further comprising means for sending, by the I/O device, a reply message to the application program over the virtual connection.

10. The system of claim 8, wherein the registering means comprises means for providing access rights to the I/O device thereby allowing the I/O device to access the application program'"'"'s memory.

11. The system of claim 8, wherein the application program is executed by a computer system having an operating system and the creating means comprises means for creating a connection between a network interface controller coupled to the system area network and a process of the application program, the connection not requiring performance of kernel services by the operating system.

12. The system of claim 8, wherein the request message further comprises a memory handle for protected access of the application program'"'"'s memory.

13. An apparatus for controlling I/O operations of an I/O device by an application program comprising:

a system area network providing communications between the application program and the I/O device, the system area network comprising a virtual connection within the system area network between the application program and the I/O device;

an operating system module resident in the application program to register the application program'"'"'s memory with the system area network and to send a request message for I/O service directly to the I/O device over the virtual connection, the request message including a virtual address of the application program'"'"'s memory; and

a device driver module coupled to the I/O device and the system area network to transfer I/O data between the I/O device and the application program'"'"'s memory specified by the virtual address over the virtual connection.

14. The apparatus of claim 13, wherein the operating system module provides access rights to the I/O device thereby allowing the I/O device to access the application program'"'"'s memory.

15. The apparatus of claim 13, wherein the application program is executed by a computer system having an operating system and further comprising a connection between a network interface controller coupled to the system area network and a process of the application program, the connection not requiring performance of kernel services by the operating system.

16. The apparatus of claim 13, wherein the request message further comprises a memory handle for accessing the application program'"'"'s memory and an identifier of a process of the application program that registered the memory.