System for determining mapping of logical objects in a computer system

• US 6,542,909 B1
• Filed: 06/30/1998
• Issued: 04/01/2003
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: Emc IP Holding Company LLC (Dell Technologies Inc.)
• Original Assignee: EMC Corporation (Dell Technologies Inc.)
• Inventors: Tamer, Philip E., Hoffman, Jane E.
• Primary Examiner(s): Rones, Charles
• Application Number:
  US09/108,038
• Time in Patent Office: 1,736 Days
• Field of Search: 707/205, 707/1, 707/204, 707/202, 707/103, 707/100, 707/104.1, 707/203, 714/6, 714/20, 709/203, 711/112, 711/170, 711/167, 711/4, 711/165, 711/162, 711/114, 370/392, 370/414, 713/100
• US Class Current: 707/756
• CPC Class Codes: G06F 9/4493 Object persistence
• CPC Class Codes: Y10S 707/955 Object-oriented
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99956 File allocation

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 computer readable medium encoded with a program for execution on a host computer that is coupled to a storage device and includes at least one mapping layer that maps logical objects on the host computer to storage locations on the storage device, the at least one mapping layer including at least one of a file system mapping layer, a logical volume mapping layer, and a database mapping layer, the program, when executed on the host computer, performing a method comprising a step of:

providing an application program that executes on the host computer with information pertaining to a manner in which a logical object is mapped through the at least one mapping layer.

2. The computer readable medium of claim 1, wherein the step of providing includes a step of providing to the application program information identifying a storage location on the storage device to which the logical object is mapped.

3. The computer readable medium of claim 1, wherein the step of providing includes a step of providing to the application program information identifying an organizational structure of the at least one mapping layer through which the logical object is mapped.

4. A computer system comprising:

a host computer;

a storage system that is coupled to the host computer and includes at least one storage device;

at least one mapping layer that is mounted on at least one of the host computer and the storage system that maps logical objects on the host computer to storage locations on the at least one storage device, the at least one mapping layer including at least one of a file system mapping layer, a logical volume mapping layer, and a database mapping layer; and

means for providing information pertaining to a manner in which a logical object on the host computer is mapped through the at the at least one mapping layer to an application program that executes on the host computer.

5. The computer system of claim 4, wherein the at least one mapping layer is mounted on the host computer.

6. The computer system of claim 4, wherein the at least one mapping layer is mounted on the storage system.

7. The computer system of claim 4, wherein the at least one mapping layer includes a plurality of mapping layers including a first mapping layer that is mounted on the host computer and a second mapping layer that is mounted on the storage system.

8. In a computer system having a host computer, a storage device and at least one mapping layer that maps logical objects on the host computer to storage locations on the storage device, the at least one mapping layer including at least one of a file system mapping layer, a logical volume mapping layer, and a database mapping layer, a method comprising a step of:

providing to an application program that executes on the host computer information pertaining to a manner in which a logical object is mapped through the at least one, mapping layer.

9. The method of claim 8, wherein the step of providing includes a step of providing to the application program information identifying a storage location on the storage device to which the logical object is mapped.

10. The method of claim 9, wherein the step of providing includes a step of providing to the application program information identifying each storage location on the storage device to which the logical object is mapped.

11. The method of claim 8, wherein the at least one mapping layer includes a plurality of mapping layers, each of the plurality of mapping layers mapping the logical object to at least one location in a next lower mapping layer of the plurality of mapping layers, a lowest mapping layer of the plurality of mapping layers mapping the logical object to at least one storage location on the storage device, and wherein the step of providing includes a step of providing to the application program information identifying the at least one storage location on the storage device to which the logical object is mapped.

12. The method of claim 11, further comprising a step of:

determining which of the plurality of mapping layers are associated with mapping the logical object;

wherein the step of providing includes a step of iteratively mapping the logical object through each of the plurality of mapping layers that are associated with mapping the logical object to identify the at least one storage location on the storage device to which the logical object is mapped.

13. The method of claim 11, wherein the step of providing includes a step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped.

14. The method of claim 13, wherein:

the computer system includes a storage system that is coupled to the host computer and includes the storage device; and

the lowest mapping layer includes a storage system mapping layer that is mounted on the storage system.

15. The method of claim 14, wherein the storage system mapping layer maps storage locations perceived by the computer system as being physical storage locations on the host computer to the storage locations on the storage device, and wherein the step of providing further includes a step of providing to the application program information identifying each of the perceived physical storage locations to which the logical object is mapped.

16. The method of claim 13, further comprising a step of:

determining which of the plurality of mapping layers are associated with mapping the logical object.

17. The method of claim 16, wherein the step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped includes a step of iteratively mapping the logical object through each of the plurality of mapping layers that are associated with mapping the logical object to identify each of the at least one storage locations on the storage device to which the logical object is mapped.

18. The method of claim 8, wherein the step of providing includes a step of providing to the application program information identifying an organizational structure of the at least one mapping layer through which the logical object is mapped.

19. In a computer system having a host computer, a storage device and at least one mapping layer that maps logical objects on the host computer to storage locations on the storage device, a method comprising a step of:

providing to an application program that executes on the host computer information pertaining to a manner in which a logical object is mapped through the at least one mapping layer;

wherein the at least one mapping layer includes a plurality of mapping layers, each of the plurality of mapping layers mapping the logical object to at least one location in a next lower mapping layer of the plurality of mapping layers, a lowest mapping layer of the plurality of mapping layers mapping the logical object to at least one storage location on the storage device, and wherein the step of providing includes a step of providing to the application program information identifying the at least one storage location on the storage device to which the logical object is mapped;

wherein the step of providing further includes a step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped;

wherein the logical object is a database object, wherein a first mapping layer of the plurality of mapping layers is a database mapping layer, wherein the lowest mapping layer is a logical volume manager mapping layer, and wherein the step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped includes steps of;

mapping the database object through the database mapping layer to determine at least one identifier in the logical volume manager mapping layer to which the database object is mapped; and

mapping each of the at least one identifiers through the logical volume manager mapping layer to identify each of the at least one storage locations on the storage device to which the database object is mapped.

20. In a computer system having a host computer, a storage device and at least one mapping layer that maps logical objects on the host computer to storage locations on the storage device, a method comprising a step of:

providing to an application program that executes on the host computer information pertaining to a manner in which a logical object is mapped through the at least one mapping layer;

wherein the at least one mapping layer includes a plurality of mapping layers, each of the plurality of mapping layers mapping the logical object to at least one location in a next lower mapping layer of the plurality of mapping layers, a lowest mapping layer of the plurality of mapping layers mapping the logical object to at least one storage location on the storage device, and wherein the step of providing includes a step of providing to the application program information identifying the at least one storage location on the storage device to which the logical object is mapped;

wherein the step of providing further includes a step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped;

wherein the logical object is a database object, wherein a first mapping layer of the plurality of mapping layers is a database mapping layer, wherein the next mapping layer is a file system mapping layer, wherein the lowest mapping layer is a logical volume manager mapping layer, and wherein the step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped includes steps of;

mapping the database object through the database mapping layer to determine a file to which the database object is mapped;

mapping the file through the file system mapping layer to determine at least one identifier in the logical volume manager mapping layer to which the file is mapped; and

mapping each of the at least one identifiers through the logical volume manager mapping layer to identify each of the at least one storage locations on the storage device to which the database object is mapped.

21. In a computer system having a host computer, a storage device and at least one mapping layer that maps logical objects on the host computer to storage locations on the storage device, a method comprising a step of:

providing to an application program that executes on the host computer information pertaining to a manner in which a logical object is mapped through the at least one mapping layer;

wherein the at least one mapping layer includes a plurality of mapping layers, each of the plurality of mapping layers mapping the logical object to at least one location in a next lower mapping layer of the plurality of mapping layers, a lowest mapping layer of the plurality of mapping layers mapping the logical object to at least one storage location on the storage device, and wherein the step of providing includes a step of providing to the application program information identifying the at least one storage location on the storage device to which the logical object is mapped;

wherein the step of providing further includes a step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped;

wherein the logical object is a file, wherein a first mapping layer of the plurality of mapping layers is a file system mapping layer, wherein the lowest mapping layer is a logical volume manager mapping layer, and wherein the step of providing to the application program information identifying each of the at least one storage locations on the storage device to which the logical object is mapped includes steps of;

mapping the file through the file system mapping layer to determine at least one identifier in the logical volume manager mapping layer to which the file is mapped; and

mapping each of the at least one identifiers through the logical volume manager mapping layer to identify each of the at least one storage locations on the storage device to which the file is mapped.