Method and apparatus for initializing logical objects in a data storage system

• US 7,127,556 B2
• Filed: 09/29/2004
• Issued: 10/24/2006
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: EMC Corporation (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Vishlitzky, Natan, Blumenau, Steven M., Tamer, Philip E.
• Primary Examiner(s): Choi, Woo H.
• Application Number:
  US10/953,936
• Publication Number:
  US 20050044312A1
• Time in Patent Office: 755 Days
• Field of Search: 711/1, 711/165, 711/166, 711/111, 711/112, 710/33
• US Class Current: 711/113
• CPC Class Codes: G06F 3/061 Improving I/O performance
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0683 Plurality of storage devices

Abstract

A method and apparatus for manipulating data in a storage device that is coupled to a host computer. Manipulations that can be performed by the storage device include moving non-contiguous blocks of data between the host computer and the storage device in a single operation. Other manipulations can be performed directly by the storage device without passing data to or from the host computer and include copying data from one logical object that is defined on the host computer to another, initializing, backing-up, transforming, or securely deleting a logical object that is defined by the host computer with a single command. In one embodiment, an application programming interface is provided that allows a relationship between logical objects on a host computer and storage locations on a storage device to be communicated between the host computer and the storage device. By providing the storage device with knowledge of the relationship between a logical object and the storage locations corresponding to that logical object, data corresponding to the logical object can be manipulated directly by the storage device, rather than by the host computer. In another embodiment, a graphical visualization routine is provided that displays the global mapping of a logical object to a set of physical blocks on the storage device for each layer of mapping below the logical object.

Claims

1. A storage system for use in a computer system including a host computer, the storage system comprising:

at least one storage device having a plurality of user-accessible storage locations, the at least one storage device including at least one disk drive;

a cache memory; and

a controller, coupled to the cache memory and the at least one storage device, that controls access to the at least one storage device from the host computer, so that the at least one storage device is accessible to the host computer only via the controller, the controller being capable of generating data that is independent of any data passed from the host computer to the storage system and writing the generated data to at least two non-contiguous user-accessible storage locations on the at least one storage device in response to a communication from the host computer that specifies the at least two non-contiguous user-accessible storage locations and does not include the generated data to be written to the at least two non-contiguous user-accessible storage locations, without writing the generated data to at least one user-accessible storage location disposed between the at least two non-contiguous storage locations so that any data in the at least one user-accessible storage location is preserved.

2. The storage system of claim 1, wherein the controller is capable of generating the data that is independent of any data passed from the host computer to the storage system and writing the generated data to the at least two non-contiguous user-accessible storage locations in response to a single command.

3. The storage system of claim 2, wherein the controller is capable of generating the data that is independent of any data passed from the host computer to the storage system having a predetermined state and writing the generated data having the predetermined state to each of the at least two non-contiguous user-accessible storage locations in response to the single command.

4. The storage system of claim 2, wherein the at least one storage device includes a plurality of disk drives, wherein the at least two non-contiguous user-accessible storage locations are perceived by the host computer to be non-contiguous storage locations on different disk drives, and wherein the controller is capable of writing the generated data to each of the at least two non-contiguous user-accessible storage locations in response to a single command.

5. The storage system of claim 4, wherein the controller is capable of writing the generated data to only each of the at least two non-contiguous user-accessible storage locations in response to the single command.

6. The storage system of claim 2, wherein the at least one storage device includes a plurality of disk drives, wherein the at least two non-contiguous user accessible storage locations are on different disk drives, and wherein the controller is capable of writing the generated data to each of the at least two non-contiguous user-accessible storage locations in response to the single command.

7. The storage system of claim 4, wherein the single command separately identifies the at least two non-contiguous user-accessible storage locations.

8. The storage system of claim 1, wherein the at least two non-contiguous user-accessible storage locations correspond to a logical object defined by the computer system, and wherein the controller is capable of writing the generated data to each user-accessible storage location corresponding to the logical object in response to the single command.

9. The storage system of claim 8, wherein the controller is capable of generating the data that is independent of any data passed from the host computer to the storage system having a predetermined state and writing the generated data having the predetermined state to each user-accessible storage location corresponding to the logical object in response to the single command.

10. The storage system of claim 1, wherein the controller includes means for generating the data that is independent of any data passed from the host computer to the storage system.

11. The storage system of claim 1, wherein the at least one storage device includes a plurality of disk drives.

22. The storage system of claim 1, wherein the controller includes means, responsive to the communication, for generating the data independently of any data passed from the host computer to the storage system.

23. The storage system of claim 6, wherein the controller is capable of writing the generated data to only the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

24. The storage system of claim 8, wherein the controller is capable of writing the generated data to only those user-accessible storage locations corresponding to the logical object in response to the single command.

12. A method of operating a storage system in a computer system including the storage system and a host computer coupled thereto, wherein the storage system includes a controller, a cache memory, and at least one storage device having a plurality of user-accessible storage locations, the at least one storage device including at least one disk drive, and wherein the controller controls access to the at least one storage device so that the at least one storage device is accessible to the host computer only via the controller, the method comprising, in response to a communication received from the host computer that specifies at least two non-contiguous user-accessible storage locations on the at least one storage device, acts of:

(A) generating, within the storage system, data that is independent of any data passed from the host computer to the storage system to be written to the at least two non-contiguous user-accessible storage locations of the plurality of user-accessible storage locations on the at least one storage device; and

(B) writing the generated data to the at least two non-contiguous user-accessible storage locations without writing the generated data to at least one user-accessible storage location disposed between the at least two non-contiguous storage locations so that any data in the at least one user-accessible storage location is preserved.

13. The method of claim 12, wherein the act (B) includes an act of writing the generated data to the at least two non-contiguous user-accessible storage locations in response to a single command received from the host computer.

14. The method of claim 13, wherein the act (A) includes an act of generating the data that is independent of any data passed from the host computer to the storage system having a predetermined state to be written to each of the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

15. The method of claim 13, wherein the at least one storage device includes a plurality of disk drives, wherein the at least two non-contiguous user-accessible storage locations are perceived by the host computer to be non-contiguous storage locations on different disk drives, and wherein the act (B) includes an act of writing the generated data to each of the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

16. The method of claim 15, wherein the act (B) includes an act of writing the generated data to only each of the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

17. The method of claim 13, wherein the at least one storage device includes a plurality of disk drives, wherein the at least two non-contiguous user-accessible storage locations are on different disk drives, and wherein the act (B) includes an act of writing the generated data to each of the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

18. The method of claim 15, wherein the single command separately identifies the at least two non-contiguous user-accessible storage locations.

19. The method of claim 12, wherein the at least two non-contiguous user-accessible storage locations correspond to a logical object defined by the computer system, and wherein the act (B) includes an act of writing the generated data to each user-accessible storage location corresponding to the logical object in response to a single command received from the host computer.

20. The method of claim 19, wherein the act (A) includes an act of generating the data that is independent of any data passed from the host computer to the storage system having a predetermined state to be written to the first group in response to the single command.

25. The method of claim 17, wherein the act B includes an act of writing the generated data to only the at least two non-contiguous user-accessible storage locations in response to the single command received from the host computer.

26. The method of claims 19, wherein the act B includes an act of writing the generated data to only those user accessible storage locations corresponding to the logical object in response to the single command received from the host computer.

21. In a computer system including a storage system and a host computer coupled thereto, the storage system including, a controller, a cache memory, and at least one storage device, wherein the controller controls access to the at least one storage device so that the at least one storage device is accessible to the host computer only via the controller, a method of writing information to a logical object of the host computer, the method comprising, in response to a communication received from the host computer that specifies a plurality of storage locations on the at least one storage device corresponding to the logical object of the host computer, the plurality of storage locations comprising at least two storage locations that are perceived by the host computer to be non-contiguous, acts of:

(A) generating, within the storage system, data that is independent of any data passed from the host computer to the storage system to be written to the plurality of storage locations on the at least one storage device corresponding to the logical object of the host computer; and

(B) writing the generated data to only the plurality of storage locations corresponding to the logical object.

27. The method of claim 21, further comprising an act of mapping the logical object on the host computer to the plurality of storage locations on the at least one storage device corresponding to the logical object.

28. In a computer system including a storage system and a host computer coupled thereto, the storage system including a controller and at least one storage device having a plurality of storage locations, wherein the controller controls access to the at least one storage device so that the at least one storage device is accessible to the host computer only via the controller, a method of writing information to a logical object of the host computer, comprising acts of:

mapping the logical object to a group of storage locations, from among the plurality of storage locations, on the at least one storage device that are assigned to store the information for the logical object, the group of storage locations comprising at least two storage locations that are perceived by the host computer to be non-contiguous;

receiving, at the storage system, a communication from the host computer identifying the group of storage locations; and

generating, within the storage system, data that is independent of any data passed from the host computer to the storage system and writing the generated data to the group of storage locations in response to the act of receiving the communication.

29. The method of claim 28, wherein the host computer includes at least one mapping layer, and wherein the act of mapping includes an act of mapping the logical object through the at least one mapping layer on the host computer to the group of storage locations on the at least one storage device.

30. The method of claim 29, wherein the at least one mapping layer includes a plurality of mapping layers including at least one of a file system mapping layer, a logical volume mapping layer, and a database mapping layer, and wherein the act of mapping includes an act of mapping the logical object through at least one of the file system mapping layer, the logical volume mapping layer, and the database mapping layer on the host computer to the group of storage locations on the at least one storage device.

31. The method of claim 28, wherein the storage system includes a storage system mapping layer, and wherein the act of mapping includes an act of mapping the logical object through the storage system mapping layer to the group of storage locations on the at least one storage device.

32. The method of claim 28, wherein each storage location of the group of storage locations is assigned to store the information for the logical object, and wherein the act of mapping includes an act of mapping the logical object of the host computer to each storage location of the group of storage locations on the at least one storage device.

33. The method of claim 32, wherein the act of receiving includes an act of receiving, at the storage system, a communication from the host computer identifying each storage location of the group of storage locations on the at least one storage device that is assigned to store the information for the logical object.

34. The method of claim 33, wherein the act of generating and writing includes an act of generating data and writing the generated data to each storage location of the group of storage locations on the at least one storage device that is assigned to store the information for the logical object.

35. The method of claim 34, wherein the act of generating and writing includes an act of generating data and writing the generated data to only the group of storage locations on the at least one storage device that are assigned to store the information for the logical object.

36. The method of claim 34, wherein the at least two storage locations that are perceived by the host computer to be non-contiguous are perceived by the host computer to be non-contiguous storage locations on a same storage device.

37. The method of claim 34, wherein the at least two storage locations that are perceived by the host computer to be non-contiguous are perceived by the host computer as being located on different storage devices.

38. The method of claim 34, wherein the at least one storage device includes a plurality of disk drives, and wherein at least two storage locations of the group of storage locations are located on different disk drives.

39. The method of claim 34, wherein the at least one storage device includes a first disk drive, and wherein at least two storage locations of the group of storage locations are non-contiguous storage locations on the first disk drive.

40. The method of claim 28, wherein the act of mapping is performed on the host computer.

41. The method of claim 28, wherein each storage location of the group of storage locations is assigned to store the information for the logical object, and wherein the act of receiving includes an act of receiving, at the storage system, a communication from the host computer identifying each storage location of the group of storage locations on the at least one storage device that is assigned to store the information for the logical object.

42. The method of claim 28, wherein each storage location of the group of storage locations is assigned to store the information for the logical object, and wherein the act of generating and writing includes an act of generating data and writing the generated data to each storage location of the group of storage locations on the at least one storage device that is assigned to store the information for the logical object.

43. The method of claim 42, wherein the act of generating and writing includes an act of generating data and writing the generated data to only the group of storage locations on the at least one storage device that are assigned to store the information for the logical object.

44. The method of claim 42, wherein the at least two storage locations that are perceived by the host computer to be non-contiguous are perceived by the host computer to be non-contiguous storage locations on a same storage device.

45. The method of claim 42, wherein the at least two storage locations that are perceived by the host computer to be non-contiguous are perceived by the host computer as being located on different storage devices.

46. The method of claim 42, wherein the at least one storage device includes a plurality of disk drives, and wherein at least two storage locations of the group of storage locations are located on different disk drives.

47. The method of claim 42, wherein the at least one storage device includes a first disk drive, and wherein at least two storage locations of the group of storage locations are non-contiguous storage locations on the first disk drive.

48. The method of claim 28, wherein the act of generating and writing includes an act of generating data having a predetermined state and writing the generated data having the predetermined state to the group of storage locations on the at least one storage device.