Software recovery method for flash media with defective formatting

• US 7,526,675 B2
• Filed: 06/23/2006
• Issued: 04/28/2009
• Est. Priority Date: 08/16/2002
• Status: Expired due to Fees

• Current Assignee: MCM Portfolio LLC
• Original Assignee: MCM Portfolio LLC
• Inventors: Thiagaraian, Shanmugavelu, Govindaraju, Jothikumar, Mambakkam, Sreenath
• Primary Examiner(s): Lohn; Joshua A
• Application Number:
  US11/473,823
• Publication Number:
  US 20060242460A1
• Time in Patent Office: 1,040 Days
• Field of Search: 714/2, 714/5, 714/15
• US Class Current: 714/15
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G11C 2029/0407 on power on
• CPC Class Codes: G11C 29/765 in solid state disks

Abstract

A method and software program for recovering data from corrupted flash media. In one aspect, the method employs a low-level access scheme that enables data to be recovered when high-level interfaces, such as file systems, are damaged. The type of flash media is determined, and a corresponding access scheme is employed. Depending on the type of damage to the media, a physical-to-logical table may be built and employed to sequentially access the flash media in search of indicia from which selectable file-types can be identified, or the media may be accessed using normal operating system commands. Once the file indicia are found, the location of corresponding file data is identified, whereupon the file data are read and stored. The software program employs an application program interface (API) comprising one or more sets of pass-through commands to enable low-level access to the flash media and to build the physical-to-logical table.

Claims

1. A system comprising:

a computing device;

a flash storage media;

a flash adapter to interface the computing device with the flash storage media; and

a firmware to perform operations to recover data from the flash storage media comprising;

accessing raw flash data stored on the flash storage media using a low-level access mechanism;

searching the raw flash data for file indicia corresponding to a selected file type;

reading data from the raw flash data based on information in the file indicia, said data comprising a recovered file;

defining an application program interface (API) comprising a plurality of respective sets of pass-through commands, each respective set to enable the firmware to low-level access a particular media type of flash storage media corresponding to that set of pass-through commands; and

building a physical-to-logical table with the firmware using the set of pass-through commands corresponding to the media type of the flash storage media.

2. The system of claim 1, wherein the flash adapter is a standalone device.

3. The system of claim 1, wherein the flash adapter is removable from the computing device.

4. The system of claim 1, wherein the flash adapter is integrated to the computing device.

5. The system of claim 1, wherein the computing device is a cellular telephone.

6. The system of claim 1, wherein the computing device is a personal digital assistant (PDA).

7. The system of claim 1, wherein the computing device is a digital camera.

8. The system of claim 1, wherein the computing device further comprises a Universal Serial Bus (USB) port.

9. The system of claim 1, wherein the flash storage media comprises a device compatible with memory sold under the trademark SMARTMEDIA.

10. The system of claim 1, wherein the flash storage media comprises a device compatible with memory sold under the trademark MEMORY STICK.

11. The system of claim 1, wherein the firmware resides at the flash storage media.

12. The system of claim 1, wherein the firmware resides at the computing device.

13. A system comprising:

a computing device;

a flash storage media;

a flash adapter to interface the computing device with the flash storage system media; and

a firmware to perform operations to recover data from the flash storage media comprising;

determining a media type of the flash storage media;

building a physical-to-logical table mapping physical storage locations to logical storage locations based on the media type of flash storage media;

accessing raw flash data stored on the flash storage media using the physical-to-logical table;

searching for a file header corresponding to a selected file type;

reading data from the raw flash data based on information in the file header, said data comprising a recovered file;

defining an application program interface (API) comprising a plurality of respective sets of pass-through commands, each respective set to enable the firmware to low-level access a particular media type of flash storage media corresponding to that set of pass-through commands; and

building the physical-to-logical table with the firmware using the set of pass-through commands corresponding to the media type of the flash storage media.

14. The system of claim 13, wherein the flash adapter is a standalone device.

15. The system of claim 13, wherein the flash adapter is removable from the computing device.

16. The system of claim 13, wherein the flash adapter is integrated with the computing device.

17. The system of claim 13, wherein the computing device is a cellular telephone.

18. The system of claim 13, wherein the computing device is a personal digital assistant (PDA).

19. The system of claim 13, wherein the computing device further comprises a Universal Serial Bus (USB) port.

20. The system of claim 13, wherein the flash storage media comprises a device compatible with memory sold under the trademark SMARTMEDIA.

21. The system of claim 13, wherein the flash storage media comprises a device compatible with memory sold under the trademark MEMORY STICK.

22. A method for recovering data from a flash storage media comprising:

determining the validity of a master boot record and a disk boot record;

selecting one of a first physical sector, a first logical sector and a data area as a starting sector depending on the validity of the master boot record and the disk boot record;

accessing raw flash data stored on the flash storage media using a low-level access mechanism;

searching the raw flash data beginning with the start sector for file indicia corresponding to a selected file type;

reading data from the raw flash data based on information in the file indicia, said data comprising a recovered file;

defining an application program interface (API) comprising a plurality of respective sets of pass-through commands, each respective set enabling low-level access to a particular media type of flash storage media corresponding to that set of pass-through commands; and

building a physical-to-logical table using the set of pass-through commands corresponding to the media type of the flash storage media.

23. A method for recovering data from a flash storage media comprising:

determining a media type of the flash storage media;

building a physical-to-logical table mapping physical storage locations to logical storage locations based on the media type of flash storage media;

accessing raw flash data stored on the flash storage media using the physical-to-logical table;

searching for a file header corresponding to a selected file type; and

reading data from the raw flash data based on information in the file header, said data comprising a recovered file.

24. The method of claim 23 further comprising:

defining an application program interface (API) comprising a plurality of respective sets of pass-through commands, each respective set enabling low-level access to a particular type of flash storage media corresponding to that set of pass-through commands; and

building the physical-to-logical table using the set of pass-through commands corresponding to the media type of the flash storage media.

25. The method of claim 23, further comprising providing firmware to perform the determining, the building, the accessing, the searching, and the reading.

26. The method of claim 25, wherein the firmware resides at the flash storage media.

27. The method of claim 25, wherein the firmware resides at the computing device.

28. The method of claim 23, further comprising:

providing a computing device to perform the determining, the building, the accessing, the searching, and the reading; and

providing a flash adapter to interface the computing device with the flash storage media.

29. The method of claim 28, wherein the flash adapter is a standalone device.

30. The method of claim 28, wherein the flash adapter is removable from the computing device.

31. The method of claim 28, wherein the flash adapter is integrated with the computing device.

32. The method of claim 28, wherein the computing device is a cellular telephone.

33. The method of claim 28, wherein the computing device is a digital camera.

34. The method of claim 28, wherein the computing device is a personal digital assistant (PDA).

35. The method of claim 28, wherein the computing device is a digital camera.

36. The method of claim 28, wherein the computing device further comprises a Universal Serial Bus (USB) port.

37. The method of claim 28, wherein the flash storage media comprises a device compatible with memory sold under the trademark SMARTMEDIA.

38. The method of claim 28, wherein the flash storage media comprises a device compatible with memory sold under the trademark MEMORY STICK.

39. The method of claim 23, wherein the recovered file is an image.