Claims
- 1. A data structure for use by a computing device for accessing stored data in a data storage system, comprising:
structure information for identifying data structures in the data storage system; a first pointer that points to a fixed level of the stored data; and a second pointer, associated with the first pointer, that points to a portion of the structure information for the data stored at a storage location represented by the fixed level, wherein the portion of the structure information describes the data at a lower level than the fixed level.
- 2. The data structure of claim 1, wherein the fixed level is one of a volume level, cylinder level, and track level.
- 3. The data structure of claim 1, wherein the portion of the structure information further includes a third pointer to a structure level data set.
- 4. The data structure of claim 1, wherein the portion of the structure information describes the format of the data in a manner independent of the actual data.
- 5. The data structure of claim 1, further comprising metadata associated with the first pointer, the metadata identifying the second pointer.
- 6. The data structure of claim 1, wherein a same portion of the structure information is used for different portions of data stored in the data storage system.
- 7. The data structure of claim 1, wherein the portion of the structure information includes an algorithm for determining boundaries of a lower level data structure.
- 8. The data structure of claim 1, wherein the second pointer has associated metadata, and wherein the associated metadata identifies at least one of a record format description and a record count.
- 9. A method, in a computing device, for copying data from one location to another location in a data storage system, comprising:
copying a first pointer that points to a fixed level of the stored data; determining if the first pointer has an associated second pointer; and copying a second pointer associated with the first pointer, if the first pointer has an associated second pointer, wherein the second pointer points to a portion of structure information for the data stored at a storage location represented by the fixed level, wherein the portion of the structure information describes the data at a lower level than the fixed level.
- 10. The method of claim 9, further comprising:
receiving a request for copying the data from the one location to the another location.
- 11. The method of claim 10, further comprising:
setting bounds of the portion of structure information based on the portion of data to be copied identified in the received request.
- 12. The method of claim 9, wherein the steps of copying the first pointer and copying the second pointer including using an instant copy operation to perform the copying of the first pointer and the copying of the second pointer.
- 13. The method of claim 9, wherein the fixed level is one of a volume level, cylinder level, and track level.
- 14. The method of claim 9, wherein the portion of the structure information further includes a third pointer to a structure level data set.
- 15. The method of claim 9, wherein the portion of the structure information describes the format of the data in a manner independent of the actual data.
- 16. The method of claim 9, wherein determining if the first pointer has an associated second pointer includes reading metadata associated with the first pointer, wherein the associated metadata identifies the second pointer.
- 17. The method of claim 9, wherein a same portion of the structure information is used for different portions of data stored in the data storage system.
- 18. The method of claim 9, wherein the portion of the structure information includes an algorithm for determining boundaries of a lower level data structure.
- 19. The method of claim 11, wherein setting bounds of the portion of structure information includes using an algorithm provided in the structure information for determining boundaries of a lower level data structure.
- 20. The method of claim 9, wherein the second pointer has associated metadata, and wherein the associated metadata identifies at least one of a record format description and a record count.
- 21. A computer program product in a computer readable medium for copying data from one location to another location in a data storage system comprising:
first instructions for copying a first pointer that points to a fixed level of the stored data; second instructions for determining if the first pointer has an associated second pointer; and third instructions for copying a second pointer associated with the first pointer, if the first pointer has an associated second pointer, wherein the second pointer points to a portion of structure information for the data stored at a storage location represented by the fixed level, wherein the portion of the structure information describes the data at a lower level than the fixed level.
- 22. The computer program product of claim 21, further comprising:
fourth instructions for receiving a request for copying the data from the one location to the another location.
- 23. The computer program product of claim 22, further comprising:
fifth instructions for setting bounds of the portion of structure information based on the portion of data to be copied identified in the received request.
- 24. The computer program product of claim 21, wherein the first and third instructions include instructions for using an instant copy operation to perform the copying of the first pointer and the copying of the second pointer, respectively.
- 25. The computer program product of claim 21, wherein the fixed level is one of a volume level, cylinder level, and track level.
- 26. The computer program product of claim 21, wherein the portion of the structure information further includes a third pointer to a structure level data set.
- 27. The computer program product of claim 21, wherein the portion of the structure information describes the format of the data in a manner independent of the actual data.
- 28. The computer program product of claim 21, wherein the second instructions for determining if the first pointer has an associated second pointer include instructions for reading metadata associated with the first pointer, wherein the associated metadata identifies the second pointer.
- 29. The computer program product of claim 21, wherein a same portion of the structure information is used for different portions of data stored in the data storage system.
- 30. The computer program product of claim 21, wherein the portion of the structure information includes an algorithm for determining boundaries of a lower level data structure.
- 31. The computer program product of claim 23, wherein the third instructions for setting bounds of the portion of structure information include instructions for using an algorithm provided in the structure information for determining boundaries of a lower level data structure.
- 32. The computer program product of claim 21, wherein the second pointer has associated metadata, and wherein the associated metadata identifies at least one of a record format description and a record count.
- 33. An apparatus for copying data from one location to another location in a data storage system, comprising:
means for copying a first pointer that points to a fixed level of the stored data; means for determining if the first pointer has an associated second pointer; and means for copying a second pointer associated with the first pointer, if the first pointer has an associated second pointer, wherein the second pointer points to a portion of structure information for the data stored at a storage location represented by the fixed level, wherein the portion of the structure information describes the data at a lower level than the fixed level.
RELATED APPLICATIONS
[0001] The present application is related to commonly assigned and copending U.S. patent application entitled “APPARATUS AND METHOD FOR INSTANT COPY OF DATA,” Ser. No. 09/884,822, Attorney Docket Number 2001-005-DSK and U.S. patent application entitled “APPARATUS AND METHOD FOR INSTANT COPY OF DATA IN A DYNAMICALLY CHANGEABLE VIRTUAL MAPPING ENVIRONMENT,” Ser. No. 09/884,687, Attorney Docket Number 2001-006-DSK, both of which filed on Jun. 19, 2001 and hereby incorporated by reference.