SAS EXPANDER FOR COMMUNICATION BETWEEN DRIVERS

• US 20130117767A1
• Filed: 11/09/2011
• Published: 05/09/2013
• Est. Priority Date: 11/09/2011
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Michael G. Myrah
• Inventors: Myrah, Michael G., Natrajan, Balaji, Black, Joseph David
• Granted Patent: US 8,732,381 B2
• Time in Patent Office: Days
• US Class Current: 719/326
• CPC Class Codes: G06F 13/102 where the programme performs an interfacing function, e.g. device driver G06F13/105 takes precedence; scheduling within device drivers G06F9/52; contention policies within device drivers G06F9/4881
• CPC Class Codes: G06F 2213/0028 Serial attached SCSI [SAS]
• CPC Class Codes: G06F 2213/0058 Bus-related hardware virtualisation

Abstract

A SAS expander that includes a virtual device manager and a communications manager. The virtual device manager is to generate a virtual device table comprising virtual device PHYs associated with virtual device drivers for host device drivers to allow communication between the host device drivers. The communications manager is to receive a request from a first host device driver of a first host to communicate with a second host device driver of a second host, and in response to receipt of the request, establish communication between the first host device driver and a virtual device PHY associated with a virtual device driver of the second host device driver.

Claims

1. A SAS expander comprising:

a virtual device manager to generate a virtual device table comprising virtual device PHYs associated with virtual device drivers for host device drivers to allow communication between the host device drivers; and

a communications manager to receive a request from a first host device driver of a first host to communicate with a second host device driver of a second host, and in response to receipt of the request, establish communication between the first host device driver and a virtual device PHY associated with a virtual device driver of the second host device driver.

2. The expander of claim 1, wherein the communications manager to receive SAS commands from hosts to allow the virtual device manager to generate the virtual device PHYs.

3. The expander of claim 1, wherein the virtual device manager to assign unique SAS addresses to the virtual device PHYs.

4. The expander of claim 1, wherein the virtual device manager to generate SAS BROADCAST commands to notify hosts that are in communication with the SAS expander that it has generated virtual device PHYs.

5. The expander of claim 1, wherein the communications manager to receive SAS DISCOVER commands from hosts to allow the SAS expander to respond by providing the hosts with information regarding the virtual device drivers generated by the SAS expander.

6. The expander of claim 1, wherein the virtual device manager to forward commands from the first host device driver to the virtual device driver of the second host.

7. The expander of claim 1, wherein the communications manager to communicate with host device drivers associated with host controllers of the hosts.

8. A method of communication with a SAS expander comprising:

generating a virtual device table comprising virtual device PHYs associated with virtual device drivers for host device drivers to allow communication between the host device drivers;

receiving a request from a first host device driver of a first host to communicate with a second host device driver of a second host; and

in response to receipt of the request, establishing communication between the first host device driver and a virtual device PHY associated with a virtual device driver of the second host device driver.

9. The method of claim 8, further comprising receiving SAS commands from hosts to allow the virtual device manager to generate the virtual device PHYs.

10. The method of claim 8, further comprising assigning unique SAS addresses to the virtual device PHYs.

11. The method of claim 8, further comprising generating SAS BROADCAST commands to notify hosts that are in communication with the SAS expander that it has generated virtual device PHYs.

12. The method of claim 8, further comprising receiving SAS DISCOVER commands from hosts to allow the SAS expander to respond by providing the hosts with information regarding the virtual device drivers generated by the SAS expander.

13. The method of claim 8, further comprising forwarding messages from the first host device driver to the virtual device driver of the second host.

14. The method of claim 8, further comprising communicating with host device drivers associated with host controllers of the hosts.

15. A non-transitory computer-readable medium having computer executable instructions stored thereon to operate a SAS expander, the instructions are executable by a processor to:

generate a virtual device table comprising virtual device PHYs associated with virtual device drivers for host device drivers to allow communication between the host device drivers;

receive a request from a first host device driver of a first host to communicate with a second host device driver of a second host; and

in response to receipt of the request, establish communication between the first host device driver and a virtual device PHY associated with a virtual device driver of the second host device driver.

16. The computer readable medium of claim 15 further comprising instructions that if executed cause a processor to:

receive SAS commands from hosts to allow the SAS expander to generate the virtual device PHYs.

17. The computer readable medium of claim 15 further comprising instructions that if executed cause a processor to:

assign unique SAS addresses to the virtual device PHYs.

18. The computer readable medium of claim 15 further comprising instructions that if executed cause a processor to:

generate SAS BROADCAST commands to notify hosts that are in communication with the SAS expander that it has generated virtual device PHYs.

19. The computer readable medium of claim 15 further comprising instructions that if executed cause a processor to:

receive SAS DISCOVER commands from hosts to allow the SAS expander to respond by providing the hosts with information regarding the virtual device drivers generated by the SAS expander.

20. The computer readable medium of claim 15 further comprising instructions that if executed cause a processor to:

forward commands from the first host device driver to the virtual device driver of the second host.