Storage device and method for data sharing

• US 6,748,500 B2
• Filed: 03/06/2003
• Issued: 06/08/2004
• Est. Priority Date: 01/19/1996
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Akira, Yoshida, Minoru, Nakano, Toshio, Kanda, Motohiro
• Primary Examiner(s): Nguyen, Hiep T.
• Application Number:
  US10/379,571
• Publication Number:
  US 20030149836A1
• Time in Patent Office: 460 Days
• Field of Search: 711/147, 711/149, 711/112, 710/74
• US Class Current: 711/147
• CPC Class Codes: G06F 2003/0697 device management, e.g. handlers, drivers, I/O schedulers
• CPC Class Codes: G06F 3/0601 Interfaces specially adapted for storage systems
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0661 Format or protocol conversion arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/0674 Disk device
• CPC Class Codes: G06F 3/0676 Magnetic disk device
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

In a computer system including a disk subsystem having channel interface compatible to a count-key-data format and a SCSI interface compatible to a fixed length data format, the disk subsystem is connected to a CPU controlled by an open system operating system through the SCSI interface, and connected to an other CPU controlled by a main frame operating system through the channel interface. The CPU is provided with a CKD record access library and a VSAM access library which accesses in a FBA format the VSAM record stored by the other CPU in a CKD format in the disk subsystem and allows the access by an application program of the CPU as a VSAM record based on VSAM control information.

Claims

1. A computer system comprising:

a first computer;

a second computer; and

a storage system coupled to said first computer and said second computer,

wherein said storage system comprises;

a first interface, according to count key data format, for receiving first data from said first computer,

a storage device for storing the first data, and

a second interface, according to fixed length block format, coupled to said second computer,

wherein said storage device stores location information of the first data in the storage device, and

wherein said second computer obtains the location information from the storage device via the second interface, converts the obtained location information into location information in the fixed length block format, and sends an access request including the location information in fixed length block format to said storage system via the second interface.

2. A computer system according to claim 1, wherein said storage device stores data in count key data format and said storage system sends second data in count key data format, which data includes the first data, to said second computer in response to the access request issued by said second computer.

3. A computer system according to claim 1, wherein said second,interface is SCSI.

4. A computer system according to claim 2, wherein said second computer selects data portion from the second data in the count key data format and provides data stored in the data portion to an application program.

5. A computer system according to claim 4, wherein the second data is data stored in a track in the storage device on which the first data is stored.

6. A computer system comprising:

a storage system;

a first computer coupled to said storage system via a first interface according to count key data format of said storage system; and

a second computer coupled to said storage system via a second interface according to fixed length block format of said storage system,

wherein the storage system receives first data from the first computer via the first interface, and stores the first data in a storage device in the storage system, and

wherein the second computer obtains storage location information of the first data in the storage device from the storage system via the second interface, accesses the storage system in accordance with the storage location information to receive second data, which is stored on a track storing the first data in the storage device, via the second interface.

7. A computer system according to claim 6, wherein the second data is in count key data format and said second computer extracts a data portion from the second data and provides data in the data portion for an application program executed by the second computer.

8. A computer system according to claim 7, wherein the storage location information obtained by the second computer from the storage system is data in count key data format, the second computer converts the storage location information into data in fixed length block format, and sends an access request including the converted data to the storage system to access the storage system.

9. A storage system comprising:

a first interface, according to count key data format, coupled to a first computer;

a second interface, according to fixed length block format, coupled to a second computer; and

a storage device,

wherein the storage system receives first data from the first computer via the first interface, stores the first data in the storage device in the storage system, outputs location information, in count key data format, indicating storage location of the first data in the storage device via the second interface in response to a request of the second computer, receives an access request including the location information, converted by the second computer into fixed length block format, indicating storage location of the first data from the second computer via the second interface, and sends the second data including the first data based on the received location information to the second computer.

10. A storage system according to claim 9, wherein said storage device stores data in count key data format and the second data is in the count key data format.

11. A storage system according to claim 10, wherein said second interface is SCSI.

12. A storage system according to claim 10, wherein data in a data portion is selected from the second data by the second computer and the data in the data portion is used when an application program is executed on the second computer.

13. A storage system according to claim 12, wherein the second data is data stored on a track in the storage device on which the first data is stored.

14. A storage system coupled to a first computer and a second computer comprising:

a first interface for receiving first data in count key data format from the first computer;

a storage device for storing the first data; and

a second interface, according to fixed length block format, through which the storage system sends the storage location information of the first data stored in the storage device to the second computer in response to a request from the second computer, receives from the second computer an access request to the first data based on the storage location information, and sends the second data stored on a track in the storage device storing the first data to the second computer in response to the access request.

15. A storage system according to claim 14, wherein the second data sent to the second computer through the second interface is data in count key data format and data in a data portion of the second data is provided for an application program executed on the second computer.

16. A storage system according to claim 15, wherein the storage location information sent to the second computer through the second interface is data in count key data format and the access request from the second computer includes the storage location information which is converted from the count key data format to fixed length block format by the second computer.

17. A storage system according to claim 16, wherein the first interface is a channel interface and the second interface is SCSI.