Systems and methods for modifying a set of data objects

• US 7,472,254 B2
• Filed: 10/07/2004
• Issued: 12/30/2008
• Est. Priority Date: 10/10/2003
• Status: Expired due to Fees

• Current Assignee: Iora Limited (Infonic Plc)
• Original Assignee: Iora Limited (Infonic Plc)
• Inventors: Collins, Brian
• Primary Examiner(s): Bragdon; Reginald G
• Assistant Examiner(s): Dinh; Ngoc V
• Application Number:
  US10/960,133
• Publication Number:
  US 20050080823A1
• Time in Patent Office: 1,545 Days
• Field of Search: None
• US Class Current: 711/220
• CPC Class Codes: G06F 16/1787 Details of non-transparently synchronising file systems

Abstract

A system and method for generating and updating a file system on a client computer. An original file system may be compared to an updated file system and the differences between the two file systems may be defined in specific data blocks. The differences may include new data blocks, modified data blocks, and data blocks that have been deleted. The new data blocks or modified data blocks may be sent to the client computer along with reference file updates to update the file system on the client computer. A virtual file system on the client computer may be created using the set of data blocks and the reference files to point to which data blocks contain the data for specific files. As the file system is updated, new data blocks and modified data blocks may replace deleted data blocks in the set of data blocks.

Claims

1. A method, comprising:

providing a first set of data objects comprising one or more first data blocks;

providing at least one modification data block, wherein the at least one modification data block comprises a new data block not present in the first set of data objects or a modified version of a data block in the first set of data objects; and

providing at least one file offset for the at least one modification data block, wherein the file offset references a position in a maintained set of data blocks to place the at least one modification data block,

wherein the maintained set of data blocks and the at least one file offset is used to provide a current set of data objects;

wherein if the maintained set of data blocks includes at least one free data block, at least one file offset is a position in the maintained set of data blocks to overwrite at least one free data block with the at least one modification data block.

2. The method of claim 1, further comprising:

providing update information comprising the at least one modification data block and the at least one file offset corresponding to the at least one modification data block,

wherein the update information is used to update the maintained set of data blocks to provide a user with the current set of data objects.

3. The method of claim 1, wherein the at least one modification data block comprises a difference between the first set of data objects and the current set of data objects.

4. The method of claim 1, wherein if the maintained set of data blocks does not include at least one free data block, the at least one file offset is a position in the maintained set of data blocks to append the at least one modification data block to an end of the maintained set of data blocks.

5. The method of claim 1, further comprising:

providing a reference counted list comprising a status of at least one data block in the maintained set of data blocks, wherein the status indicates whether the at least one data block is free or in-use.

6. The method of claim 5, further comprising:

changing the status of at least one free data block to in-use if at least one file offset indicates that at least one modification data block should overwrite at least one free data block.

7. The method of claim 5, further comprising:

modifying the reference counted list to indicate that the at least one modification data block is appended to an end of the maintained set of data blocks if the maintained set of data objects does not include at least one free data block.

8. The method of claim 5, further comprising:

modifying the status of at least one deleted data block of the first set of data objects to indicate that the at least one deleted data block is free, wherein the at least one deleted data block comprises a data block present in the first set of data objects but not present in the current set of data objects.

9. The method of claim 1, further comprising:

maintaining a lookup table comprising a position of at least one data block of the maintained set of data blocks and a corresponding position of the at least one data block in the current set of data objects, wherein the maintained set of data blocks and the lookup table may be used to represent the current set of data objects.

10. The method of claim 9, further comprising:

preparing an entry for the lookup table including a position of at least one modification data block in the maintained set of data blocks and a position of at least one modification data block in the current set of data objects.

11. The method of claim 1, further comprising:

maintaining a directory map file identifying at least one filename in the current set of data objects.

12. The method of claim 1, further comprising:

maintaining a directory map file identifying at least one directory in the current set of data objects and identifying at least one file in the at least one directory.

13. A method, comprising:

providing at least one modification data block, wherein the at least one modification data block comprises a data block included in a current set of data objects but not included in a first set of data objects or a data block in the current set of data objects that is a modified version of a data block from the first set of data objects;

updating a maintained set of data blocks with the at least one modification data block;

maintaining a directory map file comprising a listing of directories in the current set of data objects and a listing of files in the directories; and

updating the directory map file with a new filename of a filename not in the first set of data objects but in the current set of data objects or removing a deleted filename of a filename in the first set of data objects but not in the current set of data objects.

14. The method of claim 13, wherein updating the maintained set of data blocks comprises placing the at least one modification data block in a position in the maintained set of data blocks indicated by at least one file offset.

15. The method of claim 13, further comprising maintaining a lookup table file, wherein the lookup table file comprises a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects.

16. The method of claim 13, further comprising:

providing a lookup table entry corresponding to at least one data block, wherein the lookup table entry comprises a position of the at least one modification data block in the maintained set of data blocks and a position of the at least one modification data block in the current set of data objects; and

updating the lookup table with the lookup table entry.

17. The method of claim 13,

wherein the directory map file comprises a listing of filenames in the current set of data objects.

18. The method of claim 13,

wherein the directory map file is a first directory map file;

the method further comprising;

providing a second directory map file, wherein the second directory map file comprises a listing of at least one directory in the current set of data objects and a listing of at least one file in the at least one directory;

providing a first directory map update for the at least one modification data block, wherein the first directory map update comprises a new filename or a deleted filename; and

updating the first directory map file with the first directory map update, wherein at least part of the updating the first directory map file is performed substantially simultaneously with the second directory map file being used to reference the maintained set of data blocks.

19. The method of claim 18, further comprising:

using the first directory map file to reference the maintained set of data blocks after the updating the first directory map file.

20. The method of claim 13, wherein the maintained set of data blocks is an active in situ set of data blocks.

21. A method, comprising:

providing at least one modification data block, wherein the at least one modification data block comprises a data block included in a current set of data objects but not included in a first set of data objects or a data block in the current set of data objects that is a modified version of a data block from the first set of data objects;

updating a maintained set of data blocks with the at least one modification data block;

providing a first lookup table file and a second lookup table file;

wherein the first lookup table file and the second lookup table file comprise a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects;

providing a first lookup table entry for the at least one modification data block, wherein the first lookup table entry comprises a position of the at least one modification data block in the maintained set of data blocks and a position of the at least one modification data block in the current set of data objects; and

updating the first lookup table file with the first lookup table entry, wherein at least part of said updating is performed substantially simultaneously with the second lookup table being used to reference the maintained set of data blocks.

22. The method of claim 21, further comprising:

using the first lookup table file to reference the maintained set of data blocks after the updating of the first lookup table file.

23. A computer readable storage medium comprising program instructions, wherein the program instructions are computer-executable to:

provide a first set of data objects comprising one or more first data blocks;

provide at least one modification data block, wherein the at least one modification data block comprises a new data block not present in the first set of data objects or a modified version of a data block in the first set of data objects; and

provide at least one file offset for the at least one modification data block, wherein the at least one file offset references a position in a maintained set of data blocks to place the at least one modification data block,

wherein the maintained set of data blocks and the at least one file offset is used to provide a current set of data objects;

wherein if the maintained set of data blocks includes at least one free data block, at least one file offset is a position in the maintained set of data blocks to overwrite at least one free data block with the at least one modification data block.

24. The computer readable storage medium of claim 23, wherein the program instructions are further computer-executable to:

provide update information comprising the at least one modification data block and the at least one file offset corresponding to the at least one modification data block,

wherein the update information is used to update the maintained set of data blocks to provide a user with the current set of data objects.

25. The computer readable storage medium of claim 23, wherein the at least one modification data block comprises a difference between the first set of data objects and the current set of data objects.

26. The computer readable storage medium of claim 23, wherein if the maintained set of data blocks does not include at least one free data block, the at least one file offset is a position in the maintained set of data blocks to append the at least one modification data block to an end of the maintained set of data blocks.

27. The computer readable storage medium of claim 23, wherein the program instructions are further computer-executable to:

provide a reference counted list comprising a status of at least one data block in the maintained set of data blocks, wherein the status indicates whether the at least one data block is free or in-use.

28. The computer readable storage medium of claim 27, wherein the program instructions are further computer-executable to:

change the status of at least one free data block to in-use if at least one file offset indicates that at least one modification data block should overwrite at least one free data block.

29. The computer readable storage medium of claim 27, wherein the program instructions are further computer-executable to:

modify the reference counted list to indicate that the at least one modification data block is appended to an end of the maintained set of data blocks if the maintained set of data objects does not include at least one free data block.

30. The computer readable storage medium of claim 27, wherein the program instructions are further computer-executable to:

modify the status of at least one deleted data block of the first set of data objects to indicate that the at least one deleted data block is free, wherein the at least one deleted data block comprises a data block present in the first set of data objects but not present in the current set of data objects.

31. The computer readable storage medium of claim 23, wherein the program instructions are further computer-executable to:

maintain a lookup table comprising a position of at least one data block of the maintained set of data blocks and a corresponding position of the at least one data block in the current set of data objects, wherein the maintained set of data blocks and the lookup table may be used to represent the current set of data objects.

32. The computer readable storage medium of claim 31, wherein the program instructions are further computer-executable to:

prepare an entry for the lookup table including a position of at least one modification data block in the maintained set of data blocks and a position of at least one modification data block in the current set of data objects.

33. The computer readable storage medium of claim 23, wherein the program instructions are further computer-executable to:

maintain a directory map file identifying at least one filename in the current set of data objects.

34. The computer readable storage medium of claim 23, wherein the program instructions are further computer-executable to:

maintain a directory map file identifying at least one directory in the current set of data objects and identifying at least one file in the at least one directory.

35. A computer readable storage medium comprising program instructions, wherein the program instructions are computer-executable to:

provide at least one modification data block, wherein the at least one modification data block comprises a data block included in a current set of data objects but not included in a first set of data objects or a data block in the current set of data objects that is a modified version of a data block from the first set of data objects;

update a maintained set of data blocks with the at least one modification data block;

maintain a directory map file comprising a listing of directories in the current set of data objects and a listing of files in the directories; and

update the directory map file with a new filename of a filename not in the first set of data objects but in the current set of data objects or removing a deleted filename of a filename in the first set of data objects but not in the current set of data objects.

36. The computer readable storage medium of claim 35, wherein updating the maintained set of data blocks comprises placing the at least one modification data block in a position in the maintained set of data blocks indicated by at least one file offset.

37. The computer readable storage medium of claim 35, wherein the program instructions are further computer-executable to:

maintain a lookup table file, wherein the lookup table file comprises a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects.

38. The computer readable storage medium of claim 35, wherein the program instructions are further computer-executable to:

provide a lookup table entry corresponding to at least one data block, wherein the lookup table entry comprises a position of the at least one modification data block in the maintained set of data blocks and a position of the at least one modification data block in the current set of data objects; and

update the lookup table with the lookup table entry.

39. The computer readable storage medium of claim 35,

wherein the directory map file comprises a listing of filenames in the current set of data objects.

40. The computer readable storage medium of claim 35, wherein the program instructions are further computer-executable to:

provide a first lookup table file and a second lookup table file;

wherein the first lookup table file and the second lookup table file comprise a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects;

provide a first lookup table entry for the at least one modification data block, wherein the first lookup table entry comprises a position of the at least one modification data block in the maintained set of data blocks and a position of the at least one modification data block in the current set of data objects; and

update the first lookup table file with the first lookup table entry, wherein at least part of said updating is performed substantially simultaneously with the second lookup table being used to reference the maintained set of data blocks.

41. The computer readable storage medium of claim 40, wherein the program instructions are further computer-executable to:

use the first lookup table file to reference the maintained set of data blocks after the updating of the first lookup table file.

42. The computer readable storage medium of claim 35,

wherein the directory map file is a first directory map file;

wherein the program instructions are further computer-executable to;

provide a second directory map file, wherein the second directory map file comprises a listing of at least one directory in the current set of data objects and a listing of at least one file in the at least one directory;

provide a first directory map update for the at least one modification data block, wherein the first directory map update comprises a new filename or a deleted filename; and

update the first directory map file with the first directory map update, wherein at least part of the updating the first directory map file is performed substantially simultaneously with the second directory map file being used to reference the maintained set of data blocks.

43. The computer readable storage medium of claim 42, wherein the program instructions are further computer-executable to:

use the first directory map file to reference the maintained set of data blocks after the updating the first directory map file.

44. A system comprising:

a CPU in communication with a network;

a memory coupled to the CPU, wherein the memory comprises program instructions executable to;

provide a first set of data objects comprising one or more first data blocks;

provide at least one modification data block, wherein the at least one modification data block comprises a new data block not present in the first set of data objects or a modified version of a data block in the first set of data objects; and

provide at least one file offset for the at least one modification data block, wherein the file offset references a position in a maintained set of data blocks to place the at least one modification data block,

wherein the maintained set of data blocks and the at least one file offset is used to provide a current set of data objects;

wherein if the maintained set of data blocks includes at least one free data block, at least one file offset is a position in the maintained set of data blocks to overwrite at least one free data block with the at least one modification data block.

45. The system of claim 44, wherein the program instructions are further executable to:

provide update information comprising the at least one modification data block and the at least one file offset corresponding to the at least one modification data block,

wherein the update information is used to update the maintained set of data blocks to provide a user with the current set of data objects.

46. The system of claim 44, wherein the at least one modification data block comprises a difference between the first set of data objects and the current set of data objects.

47. The system of claim 44, wherein if the maintained set of data blocks does not include at least one free data block, the at least one file offset is a position in the maintained set of data blocks to append the at least one modification data block to an end of the maintained set of data blocks.

48. The system of claim 44, wherein the program instructions are further executable to:

provide a reference counted list comprising a status of at least one data block in the maintained set of data blocks, wherein the status indicates whether the at least one data block is free or in-use.

49. The system of claim 48, wherein the program instructions are further executable to:

change the status of at least one free data block to in-use if at least one file offset indicates that at least one modification data block should overwrite at least one free data block.

50. The system of claim 48, wherein the program instructions are further executable to:

modify the reference counted list to indicate that the at least one modification data block is appended to an end of the maintained set of data blocks if the maintained set of data objects does not include at least one free data block.

51. The system of claim 48, wherein the program instructions are further executable to:

modify the status of at least one deleted data block of the first set of data objects to indicate that the at least one deleted data block is free, wherein the at least one deleted data block comprises a data block present in the first set of data objects but not present in the current set of data objects.

52. The system of claim 44, wherein the program instructions are further executable to:

maintain a lookup table comprising a position of at least one data block of the maintained set of data blocks and a corresponding position of the at least one data block in the current set of data objects, wherein the maintained set of data blocks and the lookup table may be used to represent the current set of data objects.

53. The system of claim 52, wherein the program instructions are further executable to:

prepare an entry for the lookup table including the position of at least one modification data block in the maintained set of data blocks and the position of at least one modification data block in the current set of data objects.

54. The system of claim 44, wherein the program instructions are further executable to:

maintain a directory map file identifying at least one filename in the current set of data objects.

55. The system of claim 44, wherein the program instructions are further executable to:

maintain a directory map file identifying at least one directory in the current set of data objects and identifying at least one file in the at least one directory.

56. A system comprising:

a CPU in communication with a network;

a memory coupled to the CPU, wherein the memory comprises program instructions executable to;

provide at least one modification data block, wherein the at least one modification data block comprises a data block included in a current set of data objects but not included in a first set of data objects or a data block in the current set of data objects that is a modified version of a data block from the first set of data objects;

update a maintained set of data blocks with the at least one modification data block;

maintain a directory map file comprising a listing of directories in the current set of data objects and a listing of files in the directories; and

update the directory map file with a new filename of a filename not in the first set of data objects but in the current set of data objects or removing a deleted filename of a filename in the first set of data objects but not in the current set of data objects.

57. The system of claim 56, wherein updating the maintained set of data blocks comprises placing the at least one modification data block in a position in the maintained set of data blocks indicated by at least one file offset.

58. The system of claim 56, wherein the program instructions are further executable to:

maintain a lookup table file, wherein the lookup table file comprises a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects.

59. The system of claim 56, wherein the program instructions are further executable to:

provide a lookup table entry corresponding to at least one data block, wherein the lookup table entry comprises the position of the at least one modification data block in the maintained set of data blocks and the position of the at least one modification data block in the current set of data objects; and

update the lookup table with the lookup table entry.

60. The system of claim 56,

wherein the directory map file comprises a listing of filenames in the current set of data objects.

61. The system of claim 56, wherein the program instructions are further executable to:

provide a first lookup table file and a second lookup table file;

wherein the first lookup table file and the second lookup table file comprise a position of data blocks in the maintained set of data blocks and a corresponding position for the data blocks in the current set of data objects;

provide a first lookup table entry for the at least one modification data block, wherein the first lookup table entry comprises a position of the at least one modification data block in the maintained set of data blocks and a position of the at least one modification data block in the current set of data objects; and

update the first lookup table file with the first lookup table entry, wherein at least part of said updating is performed substantially simultaneously with the second lookup table being used to reference the maintained set of data blocks.

62. The system of claim 61, wherein the program instructions are further executable to:

use the first lookup table file to reference the maintained set of data blocks after the updating of the first lookup table file.

63. The system of claim 56,

wherein the directory map file is a first directory map file;

wherein the program instructions are further executable to;

provide a second directory map file, wherein the second directory map file comprises a listing of at least one directory in the current set of data objects and a listing of at least one file in the at least one directory;

provide a first directory map update for the at least one modification data block, wherein the first directory map update comprises a new filename or a deleted filename; and

update the first directory map file with the first directory map update, wherein at least part of the updating the first directory map file is performed substantially simultaneously with the second directory map file being used to reference the maintained set of data blocks.

64. The system of claim 63, wherein the program instructions are further executable to:

use the first directory map file to reference the maintained set of data blocks after the updating the first directory map file.