Fabric and method for sharing an I/O device among virtual machines formed in a computer system

• US 20040187106A1
• Filed: 12/05/2003
• Published: 09/23/2004
• Est. Priority Date: 02/18/2003
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hamanaka, Naoki, Uehara, Keitaro, Tsushima, Yuji, Tanaka, Tsuyoshi, Yoshida, Daisuke, Wakai, Yoshinori
• Granted Patent: US 7,313,637 B2
• Time in Patent Office: Days
• US Class Current: 718/1
• CPC Class Codes: G06F 11/1484 involving virtual machines
• CPC Class Codes: G06F 11/2033 switching over of hardware resources
• CPC Class Codes: G06F 9/5077 Logical partitioning of resources; Management or configuration of virtualized resources specific details on emulation or internal functioning of virtual machines G06F9/455

Abstract

Disclosed herein is a computer system provided with a mechanism for connecting a single port disk to an active server and the disk to a standby server when in a fail-over processing. An “add_pci” command issued from a clustering program is used to let a control program change the allocation of a PCI slot while an interruption signal issued to a standby server permits an ACPI processing routine to hot-add a PCI card that includes the disk unit on the subject guest OS.

Claims

1. A computer system, comprising:

a plurality of virtual machines formed on a control program of a computer; and

an I/O device connected to a PCI bus of said computer and shared among said plurality of virtual machines;

wherein said computer system further includes;

a single port disposed in said I/O device and connected to said PCI bus;

PCI connection allocating means for setting a state of logical connection between selected one of said plurality of virtual machines and said port; and

I/O device switching means for updating said state of logical connection set by said PCI connection allocating means according to a control signal received from said selected virtual machine,

wherein said selected virtual machine changes its state of logical connection to said I/O device according to the setting by said PCI connection allocating means.

2. The computer system according to claim 1,

wherein said I/O device switching means includes interrupting means for updating the setting by said PCI connection allocating means and generating an interruption to notify said selected virtual machine of a change of said state of logical connection to said I/O device, and

wherein said virtual machine, when receiving said interruption, changes its state of logical connection to said I/O device according to the setting by said PCI connection allocating means.

3. The computer system according to claim 1,

wherein said selected virtual machine includes error detecting means for detecting error occurrence in another virtual machine and when such an error is detected, said virtual machine sends a predetermined control signal to said I/O device switching means.

4. The computer system according to claim 2,

wherein said virtual machine includes first and second virtual machines,

wherein said second virtual machine, when an error is detected in said first virtual machine, sends a predetermined control signal to said I/O device switching means and connects the port of said I/O device to said second virtual machine, and

wherein said control program activates said second virtual machine and lets said first virtual machine stand by.

5. A computer system, comprising:

a plurality of physical partitioned computers formed by partitioning a computer physically; and

an I/O device connected to a PCI bus of said computer and shared among said plurality of physical partitioned computers,

wherein said system further includes;

a single port disposed in said I/O device and connected to said PCI bus; and

a PCI connection allocating means for setting a state of logical connection between selected one of said plurality of physical partitioned computers and said port; and

I/O device switching means for updating said state of connection set by said PCI connection allocating means according to a control signal received from said selected physical partitioned computer,

wherein said selected physical partitioned computer changes its state of logical connection to said I/O device according to the setting by said PCI connection allocating means.

6. The computer system according to claim 5,

wherein said I/O device switching means includes interrupting means for updating the setting by said PCI connection allocating means and generating an interruption to notify said selected physical partitioned computer of a change of said state of logical connection to said I/O device, and

wherein said selected physical partitioned computer, when receiving said interruption, changes its state of logical connection to said I/O device according to said setting by said PCI connection interrupting means.

7. The computer system according to claim 5,

wherein said computer includes error detecting means for detecting error occurrence in each of said plurality of physical partitioned computers and sends a predetermined control signal to said I/O device switching means when detecting such an error.

8. The computer system according to claim 6,

wherein first and second physical partitioned computers are included in said plurality of physical partitioned computers,

wherein said error detecting means, when detecting an error in said first physical partitioned computer, sends a predetermined control signal to said I/O device switching means and connects said port of said I/O device to said second physical partitioned computer, and

wherein said computer activates said second virtual machine and lets said first virtual machine stand by.

9. An I/O device connected to a PCI bus of a computer, comprising:

a single port connected to said PCI bus; and

signal generating means for generating an interruption signal used to change the state of logical connection of said port according to a control signal received from said computer,

wherein said computer, when receiving said interruption signal, changes its state of logical connection to said port.

10. The I/O device according to claim 9,

wherein said computer includes first and second virtual machines formed therein,

wherein said signal generating means sends an interruption signal to said second virtual machine to change said logical connection of said port to said first virtual machine according to a control signal received from said first virtual machine.

11. The I/O device according to claim 9,

wherein said signal generating means generates an interruption signal and updates said allocating means for setting said state of logical connection of said port.

12. An I/O device connected to a plurality of physical partitioned computers through a PCI bus, comprising:

a single port connected to said PCI bus; and

signal generating means for sending an interruption signal to said second physical partitioned computer to change said state of logical connection of said port to said first physical partitioned computer according to a control signal received from said first physical partitioned computer included in said plurality of physical partitioned computers.

13. A method for sharing an I/O device connected to a PCI bus of a computer among a plurality of virtual machines formed on a control program of said computer,

said method including:

a step of enabling said I/O device to set a state of logical connection between selected one of said plurality of virtual machines and a single port of said I/O device connected to said PCI bus through said single port; and

a step of changing said state of logical connection between said port and said selected virtual machine according to a control signal received from said selected virtual machine.

14. The method according to claim 13,

wherein said step of changing said state of logical connection includes:

a step of changing said state of logical connection between said port and said selected virtual machine and generating an interruption to notify said selected virtual machine of a change of said state of logical connection of said I/O device; and

a step of enabling said selected virtual machine that receives said interruption to change said state of logical connection to said I/O device according to said setting of said state of logical connection.

15. The method according to claim 13,

wherein said step of changing said state of logical connection, when detecting error occurrence in any of said plurality of virtual machines, updates an allocation table for setting said state of logical connection between said port and each virtual machine, lets said error-detected virtual machine stand by and activate another virtual machine.

16. A method for sharing an I/O device connected to a PCI bus of a computer among a plurality of virtual machines formed by partitioning said computer physically,

wherein said method includes:

a step of enabling said I/O device connected to said PCI bus through its single port to set a state of logical connection between selected one of said plurality of physical partitioned computers and said port; and

a step of changing said state of logical connection to said port according to a control signal received from said selected physical partitioned computer.

17. The method according to claim 16,

wherein said step of changing said state of logical connection, when detecting error occurrence in any of said plurality of physical partitioned computers, updates an allocation table for setting a state of logical connection between said port and each physical partitioned computer, lets said error-detected physical partitioned computer stand by, and activate another physical partitioned computer.

18. A method for sharing an I/O device connected to a PCI bus of a computer among a plurality of virtual machines,

wherein said method includes:

a step of enabling said I/O device connected to said PCI bus through its single port to generate an interruption signal used to change the state of logical connection of said port according to a control signal received from any selected one of said plurality of virtual machines; and

a step of changing said state of logical connection between said port and said selected virtual machine according to said received interruption signal.