System and method of updating a first version of a data file in a contactless flash memory device

• US 7,753,281 B2
• Filed: 06/01/2006
• Issued: 07/13/2010
• Est. Priority Date: 06/01/2006
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Li, Jun, Rathbone, Thomas, Ghosh, Riddhiman, Eshghi, Kave
• Primary Examiner(s): KIM, HONG CHONG
• Application Number:
  US11/444,922
• Publication Number:
  US 20070283078A1
• Time in Patent Office: 1,503 Days
• Field of Search: 340/572.1, 330/7, 711/103, 710/13, 713/100, 235/451, 235/435, 235/492, 235/380, 235/441, 717/168, 717/169, 707/203, 707/824
• US Class Current: 235/492
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 8/65 Updates security arrangements therefor G06F21/57

Abstract

A flash memory device is powered via an RF field generated by a host unit. A contactless communication channel is established between the flash memory device and the host unit. A first version of a data file, including a first plurality of data chunks, is downloaded from the flash memory device to the host unit. A second version of the data file, including a second plurality of data chunks, is generated at the host unit. Data chunk modifications to the first plurality of data chunks necessary to generate the second plurality of data chunks are identified at the host unit. The contactless communication channel is reestablished. The identified data chunk modifications to the first plurality of data chunks are performed thereby updating the first version of the data file stored on the flash memory device to the second version of the data file.

Claims

1. A method of updating a data file stored on a flash memory device via a contactless communication channel, the method comprising:

powering a flash memory device via an RF field generated by a host unit;

establishing a contactless communication channel between the flash memory device and the host unit;

downloading a first version of a data file from the flash memory device to the host unit via the contactless communication channel, the first version of the data file comprising a first plurality of data chunks;

generating a second version of the data file at the host unit, the second version of the data file comprising a second plurality of data chunks;

identifying at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks at the host unit;

reestablishing the contactless communication channel between the flash memory device and the host unit responsive to the completion of the identification of the at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks; and

performing the at least one data chunk modification to the first plurality of data chunks stored on the flash memory device thereby updating the first version of the data file stored on the flash memory device to the second version of the data file.

2. The method of claim 1, wherein performing the at least one data chunk modification comprises deleting at least one of the first plurality of data chunks stored on the flash memory device.

3. The method of claim 1, wherein performing the at least one data chunk modification comprises adding at least one of the second plurality of data chunks to the first plurality of data chunks stored on the flash memory device.

4. The method of claim 1, wherein identifying the at least one data chunk modification to the first plurality of data chunks necessary to generated the second plurality of data chunks at the host unit further comprises:

generating a first plurality of digital signatures at the host unit, each of the first plurality of digital signatures being associated with a corresponding one of the first plurality of data chunks;

generating a second plurality of digital signatures at the host unit, each of the second plurality of digital signatures being associated with a corresponding one of the second plurality of data chunks; and

comparing the first plurality of digital signatures with the second plurality of digital signatures at the host unit to determine whether the at least one data modification of the first plurality of data chunks is necessary to generate the second plurality of data chunks.

5. The method of claim 4, wherein generating a first plurality of digital signatures comprises generating a first plurality of hash values of the first plurality of data chunks and generating a second plurality of digital signatures comprises generating a second plurality of hash values of the second plurality of data chunks.

6. The method of claim 1, wherein generating a second version of the data file comprises converting a hierarchical data structure of the second version of the data file into a serialized data byte sequence at the host unit.

7. The method of claim 6, further comprising dividing the serialized data byte sequence of the second version of the data file into a plurality of consecutive variable length data chunks at the host unit.

8. The method of claim 1, wherein downloading a first version of a data file from a flash memory device to the host unit comprises:

downloading a data file record for the first version of the data file, the data file record comprising a data file name, a data file attribute, a number of data chunks in the first plurality of data chunks, and a first plurality of data chunk record pointers, where each of the first plurality of data chunk record pointers points to a storage location of a corresponding one of a first plurality of data chunk records in the flash memory device;

downloading the first plurality of data chunk records, each of the first plurality of data chunk records corresponding to one of the first plurality of data chunks, where a first data chunk record indicates a first data chunk size, and first and second data block pointers pointing to respective first and second locations of first and second blocks of data in the flash memory device, where the first data chunk comprises the first and second blocks of data; and

downloading the first and second blocks of data.

9. The method of claim 1, further comprising logging the performance of each of the at least one data chunk modifications to the first plurality of data chunks stored on the flash memory device at the host unit.

10. The method of claim 1, further comprising downloading an entire data content of the flash memory device to the host unit via the contactless communication channel.

11. The method of claim 1, further comprising reconstructing an original data structure of the first version of the data file downloaded from the flash memory device to the host unit, the first version of the downloaded data file having a serialized data byte sequence format.

12. The method of claim 1, wherein downloading a first version of a data file from the flash memory device to the host unit comprises:

downloading a data file record for the first version of the data file, the data file record comprising a data file name, a data file attribute, and a first plurality of digital signatures, where each of the first plurality of digital signatures is associated with a corresponding one of the first plurality of data chunks; and

downloading a first plurality of data chunk files, each of the first plurality of data chunk files comprising a corresponding one of the first plurality of data chunks.

13. A computer readable medium for storing a computer program for updating a data file stored on a flash memory device comprising:

computer readable code for issuing a command to a host unit to power a flash memory device via an RF field generated by the host unit;

computer readable code for establishing a contactless communication channel between the flash memory device and the host unit;

computer readable code for downloading a first version of a data file from the flash memory device to the host unit via the contactless communication channel, the first version of the data file comprising a first plurality of data chunks;

computer readable code for generating a second version of the data file at the host unit, the second version of the data file comprising a second plurality of data chunks;

computer readable code for identifying at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks at the host unit;

computer readable code for reestablishing the contactless communication channel between the flash memory device and the host unit responsive to the completion of the identification of the at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks; and

computer readable code for issuing a command to perform the at least one data chunk modification to the first plurality of data chunks stored on the flash memory device from the host unit to the flash memory device thereby updating the first version of the data file stored on the flash memory device to the second version of the data file.

14. The computer readable medium of claim 13, wherein the computer readable code for issuing a command to perform the at least one data chunk modification comprises computer readable code for issuing a command to delete at least one of the first plurality of data chunks stored on the flash memory device.

15. The computer readable medium of claim 13, wherein the computer readable code for issuing a command to perform the at least one data chunk modification comprises computer readable code for issuing a command to add one of the second plurality of data chunks to the first plurality of data chunks stored on the flash memory device.

16. The computer readable medium of claim 13, wherein the computer readable code for identifying the at least one data chunk modification to the first plurality of data chunks necessary to generated the second plurality of data chunks at the host unit further comprises:

computer readable code for generating a first plurality of digital signatures at the host unit, each of the first plurality of digital signatures being associated with a corresponding one of the first plurality of data chunks;

computer readable code for generating a second plurality of digital signatures at the host unit, each of the second plurality of digital signatures being associated with a corresponding one of the second plurality of data chunks; and

computer readable code for comparing the first plurality of digital signatures with the second plurality of digital signatures at the host unit to determine whether the at least one data modification to the first plurality of data chunks is necessary to generate the second plurality of data chunks.

17. The computer readable medium of claim 16, wherein the computer readable code for generating a first plurality of digital signatures comprises computer readable code for generating a first plurality of hash values of the first plurality of data chunks and the computer readable code for generating a second plurality of digital signatures comprises computer readable code for generating a second plurality of hash values of the second plurality of data chunks.

18. The computer readable medium of claim 13, wherein the computer readable code for generating a second version of the data file comprises computer readable code for converting a hierarchical data structure of the second version of the data file into a serialized data byte sequence at the host unit.

19. The computer readable medium of claim 18, further comprising computer readable code for dividing the serialized data byte sequence of the second version of the data file into a plurality of consecutive variable length data chunks at the host unit.

20. The computer readable medium of claim 13, wherein the computer readable code for downloading a first version of a data file from a flash memory device to the host unit comprises:

computer readable code for downloading a data file record for the first version of the data file, the data file record comprising a data file name, a data file attribute, a number of data chunks in the first plurality of data chunks, and a first plurality of data chunk record pointers, where each of the first plurality of data chunk record pointers points to a storage location of a corresponding one of a first plurality of data chunk records in the flash memory device;

computer readable code for downloading the first plurality of data chunk records, each of the first plurality of data chunk records corresponding to one of the first plurality of data chunks, where a first data chunk record indicates a first data chunk size, and first and second data block pointers pointing to respective first and second locations of first and second blocks of data in the flash memory device, where the first data chunk comprises the first and second blocks of data; and

computer readable code for downloading the first and second blocks of data.

21. The computer readable medium of claim 13, further comprising computer readable code for logging the performance of each of the at least one data chunk modifications to the first plurality of data chunks stored on the flash memory device at the host unit.

22. The computer readable medium of claim 13, further comprising computer readable code for downloading an entire data content of the flash memory device to the host unit via the contactless communication channel.

23. The computer readable medium of claim 13, further comprising computer readable code for reconstructing an original data structure of the first version of the data file downloaded from the flash memory device to the host unit, the first version of the downloaded data file having a serialized data byte sequence format.

24. The computer readable medium of claim 13, wherein the computer readable code for downloading a first version of a data file from the flash memory device to the host unit comprises:

computer readable code for downloading a data file record for the first version of the data file, the data file record comprising a data file name, a data file attribute, and a first plurality of digital signatures, where each of the first plurality of digital signatures is associated with a corresponding one of the first plurality of data chunks; and

computer readable code for downloading a first plurality of data chunk files, each of the first plurality of data chunk files comprising a corresponding one of the first plurality of data chunks.

25. A system for updating a data file stored on a flash memory device, the method comprising:

means for powering a flash memory device via an RF field generated by a host unit;

means for establishing a contactless communication channel between the flash memory device and the host unit;

means for downloading a first version of a data file from the flash memory device to the host unit via the contactless communication channel, the first version of the data file comprising a first plurality of data chunks;

means for generating a second version of the data file at the host unit, the second version of the data file comprising a second plurality of data chunks;

means for identifying at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks at the host unit;

means for reestablishing the contactless communication channel between the flash memory device and the host unit responsive to the completion of the identification of the at least one data chunk modification to the first plurality of data chunks necessary to generate the second plurality of data chunks; and

means for performing the at least one data chunk modification to the first plurality of data chunks stored on the flash memory device thereby updating the first version of the data file stored on the flash memory device to the second version of the data file.