Method and system of providing access to a virtual storage device

• US 7,747,660 B1
• Filed: 03/24/2003
• Issued: 06/29/2010
• Est. Priority Date: 03/24/2003
• Status: Expired due to Fees

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Symantec Operating Corporation (NortonLifeLock Inc.)
• Inventors: Rajan, Basant, Borate, Milind, Varadarajan, Ganesh
• Primary Examiner(s): Alam; Hosain T
• Assistant Examiner(s): HARPER, ELIYAH STONE
• Application Number:
  US10/395,415
• Time in Patent Office: 2,654 Days
• Field of Search: 707/205, 707/1, 707/2, 707/3, 707/4, 707/5, 707/104.1, 707/100, 707/10, 711/3, 711/6
• US Class Current: 707/821
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0671 In-line storage system
• CPC Class Codes: G06F 3/0676 Magnetic disk device

Abstract

A method and system of providing access to a virtual storage device is disclosed. According to one embodiment, access is provided to a virtual storage device comprising a file system storage object to store data to be written to the virtual storage device and a storage device. According to another embodiment, the virtual storage device further comprises a file system storage object to represent the virtual storage device.

Claims

1. A computer implemented method comprising:

providing access to a virtual storage device, wherein

said virtual storage device comprises a first file system storage object and a storage device, wherein

said first file system storage object is configured to store data in block regions corresponding to block regions of said storage device; and

performing all requested write operations to said virtual storage device by performing write operations to some block region within said first file system storage object but not to any block region of said storage device.

2. The method of claim 1, wherein said virtual storage device further comprises a second file system storage object, said second file system storage object being configured to represent said virtual storage device.

3. The method of claim 1, wherein said providing comprises associating said storage device with said virtual storage device, wherein said associating comprises configuring said first file system storage object to store data to be written to said storage device.

4. The method of claim 1, wherein said storage device comprises a read-only storage device.

5. The method of claim 1, wherein said providing comprises:

reading data from said storage device in response to receipt of a read operation request for said virtual storage device.

6. The method of claim 1, wherein said providing comprises:

writing data to a region of said first file system storage object in response to receipt of a write operation request for said virtual storage device.

7. The method of claim 6, wherein said providing further comprises:

reading data from said region of said first file system storage object in response to said writing.

8. The method of claim 6, wherein said providing further comprises:

determining a result of said writing; and

synchronizing said first file system storage object and said storage device in response to said determining.

9. The method of claim 6, wherein said providing further comprises:

determining a result of said writing; and

disassociating said first file system storage object from said virtual storage device in response to said determining.

10. The method of claim 1, wherein said first file system storage object comprises a sparse file.

11. The method of claim 2, wherein said second file system storage object comprises a special file.

12. The method of claim 1, wherein said virtual storage device comprises a writable storage checkpoint and a primary file set.

13. A system comprising:

a first storage device configured to provide storage to support a virtual storage device,

wherein

said virtual storage device comprises a first file system storage object and a second storage device, wherein

said first file system storage object is stored on said first storage device and is configured to store data in block regions corresponding to block regions of said second storage device; and

a file system module to provide access to said virtual storage device, wherein

all requested write operations to said virtual storage device are performed by performing write operations to some block region within said first file system storage object but not to any block region of said second storage device.

14. The system of claim 13, wherein,

said virtual storage device further comprises a second file system storage object, wherein said second file system storage object is configured to represent said virtual storage device.

15. The system of claim 13, wherein,

said file system module comprises a file system module to associate said first file system storage object and said second storage device with said virtual storage device.

16. A computer system comprising:

means for supporting the storage of a virtual storage device, wherein

said virtual storage device comprises a first file system storage object and a first storage device,

said means for supporting the storage of said virtual storage device comprises a second storage device, and

the first file system storage object is stored on said means for supporting the storage of said virtual storage device and is configured to store data in block regions corresponding to block regions of said first storage device; and

means for providing access to said virtual storage device, wherein all requested write operations to said virtual storage device are performed by performing write operations to some block region within said first file system storage object but not to any block region of said second storage device.

17. The system of claim 16, wherein,

said virtual storage device further comprises a second file system storage object, wherein the second file system storage object is configured to represent said virtual storage device.

18. The system of claim 16, wherein

said means for providing access to said virtual storage device comprises means for associating said first file system storage object and said first storage device with said virtual storage device.

19. A computer program product comprising:

a plurality of instructions executable by a computer, wherein said plurality of instructions, when executed by said computer, cause said computer to;

provide access to a virtual storage device stored on a storage device, wherein

said virtual storage device comprises a first file system storage object and a storage device, wherein

said first file system storage object is configured to store data in block regions corresponding to block regions of said storage device, and

perform all requested write operations to said virtual storage device by performing write operations to some block region within said first file system storage object but not to any block region of said storage device; and

computer readable media, wherein said computer program product is encoded in said computer readable media.

20. The computer program product of claim 19, wherein, said virtual storage device further comprises a second file system storage object configured to represent said virtual storage device.

21. The computer program product of claim 19, wherein, said plurality of instructions executable by said computer further comprise instructions to cause said computer to associate said first file system storage object and said storage device with said virtual storage device.