Flash memory management method

• US 7,127,551 B2
• Filed: 11/15/2002
• Issued: 10/24/2006
• Est. Priority Date: 11/16/2001
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Beck, Chang-kyu
• Primary Examiner(s): Sparks, Donald
• Assistant Examiner(s): Farrokh, Hashem
• Application Number:
  US10/294,906
• Publication Number:
  US 20030101327A1
• Time in Patent Office: 1,439 Days
• Field of Search: 711/103, 711/151, 711/159, 711/163, 711/206, 714 5- 8, 714/17, 714/22, 714/710, 365/185.02, 365/185.03, 365/185.04, 365/185.11, 365/185.33, 365/218
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 12/1009 using page tables, e.g. page table structures

Abstract

A method for managing a flash memory is provided wherein logical addresses of data recorded in a data region of the flash memory are recorded in a corresponding spare region. An address mapping table is produced by scanning information recorded in the spare region. As a result, the flash memory can be embodied more effectively. In addition, it is possible to restore a mapping table even though the power is suddenly cut-off.

Claims

1. A method for managing a flash memory, the method comprising:

(a) recording logical addresses of data recorded in a data region of the flash memory in a corresponding spare region and recording deletion marks, which indicate possibilities of using the corresponding data, in the spare region;

(b) producing an address mapping table by scanning information recorded in the spare region;

(c) recording the address mapping table that is produced in the flash memory;

(d) producing a correction table that indicates changes in the address mapping table; and

(e) recording the correction table in a random access memory that is separate from the flash memory.

2. The method for managing a flash memory of claim 1, wherein the step (b) includes producing the address mapping table by scanning logical addresses recorded in a particular spare region.

3. The method for managing a flash memory of claim 1, wherein the step (a) includes recording time marks, which indicate orders of recording corresponding data, in the spare region.

4. The method for managing a flash memory of claim 1, further comprising:

(f) determining whether a number of entries of the correction table that is recorded in the random access memory exceeds a predetermined threshold,

wherein a new address mapping table is produced by scanning the information recorded in the spare region and the new address mapping table is recorded in the flash memory if the number of entries of the correction table is determined to exceed the predetermined threshold.

5. A method for managing a flash memory the method comprising:

(a) recording logical addresses of data recorded in a data region of the flash memory in a corresponding spare region and recording time marks, which indicate orders of recording corresponding data, in the spare region; and

(b) producing an address mapping table by scanning logical addresses and time marks of the data recorded in the spare region.

6. The method for managing a flash memory of claim 5, further comprising:

(c) recording the address mapping table that is produced in the flash memory;

(d) producing a correction table that indicates changes in the address mapping table; and

(e) recording the correction table in a random access memory that is separate from the flash memory.

7. The method for managing a flash memory of claim 6, further comprising:

(f) determining whether a number of entries of the correction table that is recorded in the random access memory exceeds a predetermined threshold,

wherein a new address mapping table is produced by scanning the logical addresses and the time marks recorded in the spare region and the new address mapping table is recorded in the flash memory if the number of entries of the correction table is determined to exceed the predetermined threshold.

8. A method for managing a flash memory comprising:

(a) recording logical addresses of data recorded in a data region of the flash memory in a corresponding spare region, recording time marks, which indicate orders of recording corresponding data, in the spare region, and recording deletion marks, which indicate possibilities of using the corresponding data, in the spare region; and

(b) producing an address mapping table by scanning logical addresses, time marks and deletion marks of the data recorded in the spare region.

9. The method for managing a flash memory of claim 8, further comprising:

(c) recording the address mapping table that is produced in the flash memory;

(d) producing a correction table that indicates changes in the address mapping table; and

(e) recording the correction table in a random access memory that is separate from the flash memory.

10. The method for managing a flash memory of claim 9, further comprising:

(f) determining whether a number of entries of the correction table that is recorded in the main memory exceeds a predetermined threshold,

wherein a new address mapping table is produced by scanning the logical addresses and the time marks recorded in the spare region and the new address mapping table is recorded in the flash memory if the number of entries of the correction table is determined to exceed the predetermined threshold.

11. A method for managing a flash memory, the method comprising:

(a) recording logical addresses of data recorded in a data region of the flash memory in a corresponding spare region and recording deletion marks, which indicate possibilities of using the corresponding data, in the spare region;

(b) producing an address mapping table by scanning information recorded in the spare region when a system equipped with the flash memory is booted;

(c) recording the address mapping table that is produced in the flash memory;

(d) producing a correction table that indicates changes in the address mapping table; and

(e) recording the correction table in a random access memory that is separate from the flash memory.

12. The method for managing a flash memory of claim 11, further comprising:

(f) determining whether a number of entries of the correction table that is recorded in the random access memory exceeds a predetermined threshold,

wherein a new address mapping table is produced by scanning the logical addresses and the time marks recorded in the spare region and the new address mapping table is recorded in the flash memory if the number of entries of the correction table is determined to exceed the predetermined threshold.

13. A method for managing a flash memory, the method comprising:

(a) recording writing-requested data in an empty address of a data region of the flash memory with reference to an address mapping table, and recording corresponding logical addresses in corresponding spare regions; and

(b) updating a correction table, which is separate from the address mapping table, so that physical addresses where the writing-requested data is recorded in the step (a) are mapped to the logical addresses, the correction table storing only changed contents of the address mapping table.

14. The method for managing a flash memory of claim 13, wherein the step (a) includes recording time marks indicating an order of recording corresponding data in the spare region.

15. The method for managing a flash memory of claim 14, wherein step (a) includes recording deletion marks indicating a possibility of use of corresponding data in the spare region.

16. The method for managing a flash memory of claim 13, further comprising step (d) producing an address mapping table by scanning information recorded in the spare region.

17. A method for managing a flash memory the method comprising:

(a) recording writing-requested data in an empty address of a data region of the flash memory with reference to an address mapping table, and recording corresponding logical addresses in corresponding spare regions;

(b) updating a correction table, which is separate from the address mapping table, so that physical addresses where the writing-requested data is recorded in the step (a) are mapped to the logical addresses; and

(c) marking a deletion mark indicating the possibility of use of the data recorded in the step (a) in spare regions corresponding to the physical addresses corresponding to the logical addresses with reference to the address mapping table.

18. A method for managing a flash memory, the method comprising:

(a) recording writing-requested data in an empty address of a data region of the flash memory with reference to an address mapping table, and recording corresponding logical addresses in corresponding spare regions; and

(b) updating a correction table, which is separate from the address mapping table, so that physical addresses where the writing-requested data is recorded in the step (a) are mapped to the logical addresses when a system equipped with the flash memory is booted.

19. A method for managing a flash memory, the method comprising the steps of:

(a) recording changes of an address mapping table stored in the flash memory containing mapping information of logical addresses and physical addresses in a correction table formed in a main memory;

(b) confirming whether the correction table is filled to a predetermined portion;

(c) reflecting changes recorded in the correction table to the mapping table when it is confirmed that the predetermined portion of the correction table is filled; and

(d) deleting the portions reflected to the mapping table of the contents recorded in the correction table.

20. The method for managing a flash memory of claim 19, wherein the mapping table includes deletion marks indicating a possibility of use of corresponding data.

21. The method for managing a flash memory of claim 20, wherein the mapping table is recorded by time marks indicating an order of recording corresponding data.

22. The method for managing a flash memory of claim 19, wherein the correction table has a predetermined size.

23. The method for managing a flash memory of claim 22, wherein the correction table includes deletion marks indicating a possibility of use of corresponding data.

24. The method for managing a flash memory of claim 23, wherein the correction table includes time marks indicating an order of recording corresponding data.