Memory device, electronic system, and methods associated with modifying data and a file of a memory device

• US 8,655,927 B2
• Filed: 03/09/2011
• Issued: 02/18/2014
• Est. Priority Date: 03/20/2007
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Sepulveda, Frank J.
• Primary Examiner(s): Ahn, Sangwoo
• Application Number:
  US13/043,968
• Publication Number:
  US 20110161613A1
• Time in Patent Office: 1,077 Days
• Field of Search: 707/822
• US Class Current: 707/822
• CPC Class Codes: G06F 11/1441 Resetting or repowering
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 16/1727 Details of free space management performed by the file system saving storage space on storage systems G06F3/0608; management of blocks in storage devices G06F3/064
• CPC Class Codes: G06F 16/1847 specifically adapted to static storage, e.g. adapted to flash memory or SSD
• CPC Class Codes: G06F 16/1865 Transactional file systems
• CPC Class Codes: G06F 2212/1032 Reliability improvement, data loss prevention, degraded operation etc
• CPC Class Codes: G06F 2212/2022 Flash memory
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]

Abstract

A memory device, system and method of editing a file in a non-volatile memory device is described. The memory device includes a controller and a memory array configured to copy an existing first file into a second file during editing and to maintain the first file while applying edits to the second file. When editing is completed, a first cluster pointer of the first file is redirected to point at the first cluster of the second file that has been edited.

Claims

1. A method of modifying data in a memory device, comprising:

generating a file copy within a memory device from an existing file having a first starting pointer associated therewith pointing to a first starting location of a file allocation table, the file copy having a second starting pointer associated therewith pointing to a second starting location of a file allocation table, wherein the first starting location corresponds to data of the existing file, and the second starting location corresponds to data of the file copy, wherein the second starting pointer is generated regardless of whether the data of the file copy corresponding to the second starting location is modified;

modifying the file copy; and

reassociating the first starting pointer of the existing file to point to the second starting location after completion of modifying the file copy.

2. The method of claim 1, wherein the first starting location of a file allocation table and the second starting location of a file allocation table are located within a single file allocation table.

3. The method of claim 2, wherein the single file allocation table includes pointers corresponding to all data clusters of the existing file and the file copy.

4. The method of claim 1, wherein modifying the file copy includes modifying a data cluster of the file copy having a pointer of a file allocation table associated therewith.

5. The method of claim 4, wherein modifying the data cluster of the file copy includes storing modified data in another data cluster and reassociating the pointer of a file allocation table associated with the data cluster of the file copy to point to the another data cluster.

6. The method of claim 1, wherein generating the file copy includes copying data clusters of the existing file and generating a new data cluster for each data cluster copied from the existing file.

7. The method of claim 6, wherein generating the file copy includes storing a next pointer in the second starting location, the next pointer pointing to a location of a file allocation table corresponding to one of the new data clusters of the file copy.

8. The method of claim 6, wherein generating the file copy further includes storing a next pointer in a plurality of locations of a file allocation table, wherein the next pointer in each location of the plurality points to a subsequent location of a file allocation table that corresponds to one of the new data clusters of the file copy.

9. The method of claim 8, wherein generating the file copy further includes storing an end-of-file indicator in one of the subsequent locations of a file allocation table that corresponds to a final data cluster of the file copy.

10. The method of claim 1, wherein modifying includes at least one of editing, writing, programming, erasing, and resetting data in the file copy.

25. The method of claim 1, wherein generating a file copy from an existing file includes generating a complete copy of the existing file prior to modifying the file copy.

11. A method of modifying a file of a memory device, the method comprising:

modifying a file copy of an existing file within a memory device while maintaining an association of a first starting pointer to a first location of a single file allocation table, the first location corresponding to an initial page of data of the existing file;

reassociating the first starting pointer to point to a second starting location of the single file allocation table, the second starting location corresponding to an initial page of data of the file copy; and

maintaining a second starting pointer of the file copy to point to the second starting location prior to the first starting pointer being reassociated to point to the second starting location regardless of whether the initial page of data of the file copy is modified.

12. The method of claim 11, wherein maintaining an association of a first starting pointer includes maintaining the first starting pointer stored in a root directory to point to the first starting location until after modification of the file copy is completed.

13. The method of claim 11, wherein modifying the file copy includes modifying at least one page of data of the file copy and reassociating a location of the single file allocation table to correspond to the modified at least one page of data of the file copy.

26. The method of claim 11, further comprising creating the file copy as a complete copy of the existing file prior to modifying the file copy.

14. A memory device, comprising:

a memory array; and

a controller operably coupled to the memory array, the controller configured to;

copy an existing file to generate a file copy;

modify the file copy to generate a modified file copy;

reassociate a first starting pointer from pointing to a first starting location of a file allocation table to point to a second starting location of a file allocation table after the file copy has been modified, wherein the first starting location corresponds to an initial data cluster of the existing file, the second starting location corresponds to an initial data cluster of the modified file copy; and

maintain a second starting pointer to point to the second starting location prior to the first starting pointer being reassociated to point to the second starting location regardless of whether the initial data cluster of the file copy is modified.

15. The memory device of claim 14, wherein the memory array is partitioned into a system area and a data area.

16. The memory device of claim 15, wherein the system area includes a root directory area and a file allocation table area.

17. The memory device of claim 16, wherein the file allocation table area includes a single file allocation table that includes the first starting location and the second starting location.

18. The memory device of claim 17, wherein the single file allocation table includes locations that correspond to all data clusters of the existing file and the modified file copy.

19. The memory device of claim 16, wherein the root directory area stores the first starting pointer.

20. The memory device of claim 14, wherein the controller is a control state machine.

21. The memory device of claim 14, wherein the memory array is a Flash memory array.

27. The method of claim 14, wherein the controller is further configured to copy the existing file to generate the file copy as a complete file copy prior to modification of the file copy.

22. An electronic device, comprising:

a processor; and

a memory device including a memory array coupled to the processor, the memory device configured to;

respond to a data editing request by the processor of an existing file by modifying a file copy of the existing file while retaining data clusters of the existing file and corresponding entries of a file allocation table unmodified; and

reassociate a first starting pointer from pointing to a first entry of a file allocation table to point to a second entry of a file allocation table having a second starting pointer of the file copy pointing thereto, the first entry of a file allocation table locating the existing file, and the second entry of a file allocation table locating the file copy, and wherein the second starting pointer is configured to point to the second entry prior to modification of data of the file copy directly associated with the second entry.

23. The electronic device of claim 22, wherein the memory array includes a system area having at least a file allocation table area and a root directory area, wherein the file allocation table area includes at least one file allocation table that stores both of the first entry and the second entry, and wherein the root directory area is configured to store the first starting pointer, and store a the second starting pointer that is generated with the file copy to point to the second entry of a file allocation table.

24. The electronic device of claim 23, wherein the memory array further includes a data area having at least one erasable block configured to store data clusters of the existing file and the file copy.