Extension of write anywhere file system layout

• US 8,099,576 B1
• Filed: 08/04/2008
• Issued: 01/17/2012
• Est. Priority Date: 04/30/2004
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Edwards, John K., Lewis, Blake H., English, Robert M., Hamilton, Eric, Corbett, Peter F.
• Primary Examiner(s): Bataille, Pierre-Michel
• Application Number:
  US12/185,552
• Time in Patent Office: 1,261 Days
• Field of Search: 711/114, 711/112, 711/170, 711/205, 711/206, 711/E12.001
• US Class Current: 711/170
• CPC Class Codes: G06F 16/188 Virtual file systems
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

An underlying physical volume of a storage system is an aggregate having a plurality of storage devices. The aggregate has its own physical volume block number (pvbn) space. A file system layout apportions the underlying physical volume into a plurality of virtual volumes of the storage system each having a virtual volume identification (vvid). Each virtual volume has its own virtual volume block number (vvbn) space. The block allocation structures of a virtual volume are sized to the virtual volume, and not to the underlying aggregate, to thereby allow operations that manage data served by the storage system (e.g., snapshot operations) to efficiently work over the virtual volumes. Each storage block in a virtual volume is identified by the triplet: pvbn, vvid, and vvbn.

Claims

1. A data storage system, comprising:

a processor configured to execute a storage operating system, the storage operating system, when executed, configured to organize a plurality of storage devices of the data storage system to form an aggregate of data storage devices, the aggregate of data storage devices to form a physical volume, the physical volume comprising a plurality of storage blocks, each storage block of the plurality of storage blocks comprising a physical volume block number (pvbn), the plurality of storage blocks to form a pvbn space; and

the aggregate, when formed, configured to contain a plurality of virtual volumes, wherein a first virtual volume of the plurality of virtual volumes comprises a virtual volume identification (vvid), wherein a first storage block of the plurality of storage blocks of the first virtual volume is identified by a virtual volume block number (vvbn), and wherein the first storage block of the plurality of virtual volumes is identified by the pvbn, the vvid, and the vvbn.

2. The system of claim 1, further comprising:

the aggregate of data storage devices configured with its own pvbn space.

3. The system of claim 1, further comprising:

each virtual volume of the plurality of virtual volumes configured with its own vvbn space.

4. The system of claim 1, further comprising:

wherein the storage operating system is further configured to organize the plurality of storage devices into one or more RAID groups.

5. The system of claim 1, further comprising:

wherein the pvbn space defines a storage space of the plurality of storage blocks provided by the plurality of storage devices.

6. The system of claim 1, further comprising:

wherein each vvbn space is an independent set of numbers that corresponds to locations within a file, and wherein the storage operating system is further configured to translate the locations within the file to disk block numbers (dbns) on a storage device of the plurality of storage devices.

7. The system of claim 1, further comprising:

wherein each virtual volume is configured with its own block allocation structures in its vvbn space.

8. The system of claim 7, further comprising:

wherein the block allocation structures comprise an active map, a space map, and a summary map.

9. The system of claim 1, further comprising:

wherein the storage operating system is further configured to generate a snapshot of the first virtual volume using a block allocation bitmap of the first virtual volume.

10. The system of claim 9, further comprising:

wherein the snapshot is sized to the vvbn space of the first virtual volume.

11. The system of claim 1, further comprising:

wherein the storage operating system is further configured to, when executed, generate an owner map comprising an entry for the first storage block in the aggregate, the entry comprising the pvbn indicating the pvbn of the first storage block, the vvid number indicating that the first virtual volume owns the first storage block, and the vvbn indicating the vvbn that is assigned to the first storage block within the first virtual volume.

12. The system of claim 11, further comprising:

wherein the storage operating system is further configured to, when executed, generate an index that indexes the owner map by pvbn.

13. The system of claim 1, further comprising:

wherein at least one of the plurality of storage devices comprises an optical device.

14. The system of claim 1, further comprising:

wherein at least one of the plurality of storage devices comprises an electronic random access memory.

15. The system of claim 1, further comprising:

wherein the storage operating system is further configured to, when executed, store at least one of a lun, directory, qtree, and file within the first virtual volume, wherein the at least one lun, directory, qtree, and file is identified by the pvbn, vvid, and vvbn.

16. A method for operating a data storage system, comprising:

organizing a plurality of data storage devices of the data storage system to form an aggregate of data storage devices that form a physical volume, the physical volume comprising a plurality of storage blocks, each storage block comprising a physical volume block number (pvbn), the plurality of storage blocks forming a pvbn space;

storing a plurality of virtual volumes within the aggregate, a first virtual volume of the plurality of virtual volumes comprising a virtual volume identification (vvid), and a first storage block of the plurality of storage blocks within the first virtual volume identified by a virtual volume block number (vvbn); and

identifying the first storage block in the first virtual volume by the pvbn, the vvid, and the vvbn.

17. The method of claim 16, further comprising:

configuring the aggregate of data storage devices with its own pvbn space.

18. The method of claim 16, further comprising:

configuring each virtual volume of the plurality of virtual volumes with its own vvbn space.

19. The method of claim 16, further comprising:

configuring the plurality of storage devices into one or more RAID groups.

20. The method of claim 16, further comprising:

defining by the pvbns the physical volume block number space of the plurality of storage blocks provided by the plurality of storage devices.

21. The method of claim 16, further comprising:

configuring each vvbn space as an independent set of numbers that corresponds to locations within a file, and translating the locations to disk block numbers (dbns) on a storage device of the plurality of storage devices.

22. The method of claim 16, further comprising:

configuring each virtual volume with its own block allocation structures in a vvbn space of the first virtual volume.

23. The method of claim 22, further comprising:

using the block allocation structures as an active map, a space map, and a summary map.

24. The method of claim 16, further comprising:

generating a snapshot of the first virtual volume using a block allocation bitmap within the first virtual volume.

25. The method of claim 24, further comprising:

sizing the snapshot to a vvbn space of the first virtual volume.

26. The method as in claim 16, further comprising:

defining an owner map comprising an entry for the first storage block in the aggregate, the entry comprising the pvbn indicating the pvbn of the first storage block, the vvid number indicating that the first virtual volume owns the first storage block, and the vvbn indicating that the vvbn assigned to the first storage block within the virtual volume.

27. The method as in claim 26, further comprising:

indexing the owner map by pvbn.

28. A method as in claim 16, further comprising:

storing at least one of a lun, directory, qtree, and file within the first virtual volume, wherein the at least one lun, directory, qtree, and file is identified by the pvbn, vvid, and vvbn.

29. A method as in claim 16, further comprising:

using an electronic random access memory as the storage device of the plurality of storage devices.

30. A method as in claim 16, further comprising:

using a micro-electro mechanical device as the storage device of the plurality of storage devices.

31. A non-transitory computer readable storage media stored with executable program instructions for execution by a processor, the non-transitory computer readable storage media comprising:

program instructions that organize a plurality of data storage devices of a data storage system to form an aggregate of data storage devices that form a physical volume, the physical volume comprising a plurality of storage blocks, each storage block comprising a physical volume block number (pvbn), the plurality of storage blocks forming a pvbn space;

program instructions that store a plurality of virtual volumes within the aggregate, a first virtual volume of the plurality of virtual volumes comprising a virtual volume identification (vvid), and a first storage block of the plurality of storage blocks within the first virtual volume identified by a virtual volume block number (vvbn); and

program instructions that identify the first storage block in the first virtual volume by the pvbn, the vvid, and the vvbn.