Device and method for controlling access to computer peripherals

• US 6,898,643 B2
• Filed: 06/18/2001
• Issued: 05/24/2005
• Est. Priority Date: 06/16/2000
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Joyeau, Sylvain, Sanchez-Leighton, Vicente, Abiven, Anne
• Primary Examiner(s): Gaffin, Jeffrey
• Assistant Examiner(s): CHEN, ALAN S
• Application Number:
  US09/882,301
• Publication Number:
  US 20020029311A1
• Time in Patent Office: 1,436 Days
• Field of Search: 710/3, 710 22- 28, 710/62
• US Class Current: 710/3
• CPC Class Codes: G06F 13/10 Program control for peripheral devices G06F13/14 - G06F13/42 take precedence

Abstract

The invention concerns the sharing and the controlling of access to at least one peripheral for a computer system which includes a central processing unit and at the least one peripheral which has a physical interface to the central processing unit. Specifically, a request for access is received at an address of a virtual interface, where the address of the virtual interface corresponds to the physical interface, and data is exchanged between the central processing unit and the at least one peripheral is received. The received data is modified according to at least one predetermined criterion corresponding to the address of the virtual interface.

Claims

1. A device for sharing and controlling access to at least one peripheral for a computer system which includes a central processing unit and the at least one peripheral which has a physical interface to the central processing unit, the device comprising:

request reception means for receiving a request for access at an address of a virtual interface, wherein the address of the virtual interface corresponds to the physical interface;

data reception means for receiving data to be exchanged between the central processing unit and the at least one peripheral; and

modification means for modifying the data received by said data reception means, according to at least one filtering pattern selected in accordance with the address of the virtual interface.

2. A device according to claim 1, further comprising:

a memory space reserved for the physical interface, wherein said memory space is peculiar to an application executed by the computer system; and

linking means for linking an address of the memory space to an address of the physical interface.

3. A device according to claim 1, further comprising:

a first interface with a bus connected to the central processing unit; and

a second interface with a bus connected to the at least one peripheral.

4. A device according to claim 1, wherein said modification means further comprises filtering means for filtering the received request for access, according to the at least one filtering pattern.

5. A device according to claim 1, wherein said modification means further comprises a filter for applying the filter pattern to the data received by said data reception means.

6. A device according to claim 1, further comprising transmission means for transmitting the data modified by said modification means to the physical interface if an application requests an access in a write mode, and for transmitting the data modified by said modification means to the central processing unit if the application requests the access in a red mode.

7. A method for sharing and controlling access to at least one peripheral for a computer system which includes a central processing unit and the at least one peripheral which has a physical interface to the central processing unit, the method comprising:

a request reception step of receiving a request for access at an address of a virtual interface, wherein the address of the virtual interface corresponds to the physical interface;

a data reception step of receiving data to be exchanged between the central processing unit and the at least one peripheral; and

a modification step of modifying the data received in said data reception step, according to at least one filtering pattern selected in accordance with the virtual interface.

8. A method according to claim 7, further comprising:

a linking step of linking an address of a memory space to an address of the physical interface, wherein the memory space is reserved for the physical interface, and wherein the memory space is peculiar to an application executed by the computer system.

9. A method according to claim 7, wherein the central processing unit is connected with a bus at a first interface, and wherein the at least one peripheral is connected to the bus at a second interface.

10. A method according to claim 7, wherein said modification step further comprises a filtering step of filtering the received request for access, according to the at least one filtering pattern.

11. A method according to claim 7, wherein said modification step further comprises a filtering step of applying the filter pattern to the data received by said data reception step.

12. A method according to claim 7, further comprising a transmission step of transmitting the data modified in said modification step to the physical interface if an application requests an access in a write mode, and of transmitting the data modified in said modification step to the central processing unit if the application requests the access in a read mode.

13. Computer-executable program code stored on a computer readable medium, said computer-executable program code for sharing and controlling access to at least one peripheral for a computer system which includes a central processing unit and the at least one peripheral which has a physical interface to the central processing unit, the computer-executable program code comprising:

code for performing the step of receiving a request for access at an address of a virtual interface, wherein the address of the virtual interface corresponds to the physical interface;

code for performing the step of receiving data to be exchanged between the central processing unit and the at least one peripheral; and

code for performing the step of modifying the data received in said data reception step, according to at least one filtering pattern selected in accordance with the virtual interface.