Methods of directly accessing a mass storage data device

• US 8,166,488 B2
• Filed: 01/16/2007
• Issued: 04/24/2012
• Est. Priority Date: 02/22/2002
• Status: Active Grant

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Galbo, Neal Anthony, Iman, Berhanu, Le, Ngon
• Primary Examiner(s): CAO, DIEM K
• Application Number:
  US11/654,290
• Publication Number:
  US 20070180291A1
• Time in Patent Office: 1,925 Days
• Field of Search: 707/200, 707/674, 719/321, 714/6.1, 714/763
• US Class Current: 719/321
• CPC Class Codes: G06F 11/1435 using file system or storage system metadata
• CPC Class Codes: G06F 3/0659 Command handling arrangements, e.g. command buffers, queues, command scheduling
• CPC Class Codes: G06F 3/0673 Single storage device

Abstract

Methods of directly accessing a mass storage data device without communicating through an operating system layer are useful in recovering information previously stored in the mass storage device.

Claims

1. A method of directly accessing a mass storage data device comprising:

communicating with a device driver for the mass storage data device using an application program, when the device driver and the application program are further in communication with an operating system layer;

allowing the application program to access the mass storage device through the device driver to read and write information by bypassing the operating system layer;

searching for information in the mass storage device considered damaged by the operating system layer using the application program, said damaged information being inaccessible to said operating system layer;

identifying the mass storage device; and

recovering information previously stored in the mass storage device using the application program even though the mass storage device includes damaged information by causing communication at a physical, rather than logical device level.

2. The method of claim 1, further comprising recovering valid user data files from the mass storage data device.

3. The method of claim 1, further comprising reconstructing valid user data files from the mass storage data device.

4. The method of claim 1, further comprising retrieving valid user data files from the mass storage data device that the operating system would normally consider a “

damaged”

or corrupted mass storage data device.

5. A method of directly accessing a mass storage data device comprising:

communicating with an operating system layer, through an application program interface using an application program;

directly communicating with a mass storage data device using the application program through a hardware interface layer and a hardware bus of a device driver of the mass storage data device;

accessing the mass storage data device using the application program at the physical device level, thereby circumventing the operating system layer; and

recovering information previously stored in the mass storage data device using the application program even though the mass storage data device includes damaged information by causing communication at a physical, rather than logical device level;

wherein accessing the mass storage data device at the physical device level comprises accessing the mass storage data device without using formatting information of the operating system layer.

6. The method of claim 5, further comprising reading and writing information to the mass storage data device.

7. The method of claim 5, further comprising commanding the mass storage data device with standard and vendor specified commands.

8. The method of claim 5, further comprising connecting the mass storage data device via a universal serial bus (USB).

9. A method of directly accessing a mass storage data device comprising:

communicating with a device driver for the mass storage device using an application program, when the device driver and the application program are further in communication with an operating system;

accessing the mass storage data device through the device driver to read and write information using the application program without communicating through the operating system layer to the mass storage data device;

searching for information in the mass storage data device using the application program; and

recovering information previously stored in the mass storage device using the application program;

wherein recovering information previously stored in the mass storage device comprises recovering information previously stored in the mass storage device that is inaccessible to the operating system layer.

10. The method of claim 9, wherein searching for information in the mass storage data device comprises searching header information.

11. The method of claim 10, wherein searching header information comprises searching header information at boundaries of file allocation units of the mass storage data device.

12. The method of claim 9, further comprising querying the mass storage data device directly for its device characteristics without communicating through the operating system layer to the mass storage data device.

13. The method of claim 12, further comprising obtaining a physical block size of the mass storage data device from the device characteristics.

14. The method of claim 13, further comprising:

reading operating system formatting information on the mass storage data device; and

determining if operating system specific parameters of the operating system formatting information are reasonable for the operating system layer.

15. The method of claim 14, further comprising:

if the operating system specific parameters are reasonable for the operating system layer, retrieving a file allocation unit of the operating system layer;

setting a search allocation unit to be equal to the file allocation unit of the operating system layer if the operating system specific parameters are reasonable for the operating system layer; and

setting the search allocation unit to be equal to the physical block size of the mass storage data device if the operating system specific parameters are not reasonable for the operating system layer.

16. The method of claim 15, wherein searching header information comprises searching header information at boundaries of the search allocation unit.

17. The method of claim 16, wherein searching header information comprises searching for a data pattern indicative of a particular file type.

18. The method of claim 17, further comprising recovering a data file if the header information contains the data pattern indicative of the particular file type, and searching header information at a next boundary of the search allocation unit if the header information does not contain the data pattern indicative of the particular file type.

19. A method of directly accessing a mass storage data device comprising:

communicating with the mass storage data device through a device driver, wherein the device driver has a first interface for communicating with an operating system layer, and a second interface for communicating with an application program without communicating through the operating system layer;

accessing the mass storage data device using the application program to read and write information through the second interface;

searching for information in the mass storage data device using the application program through the second interface; and

recovering information previously stored in the mass storage data device using the application program through the second interface;

wherein recovering information previously stored in the mass storage data device comprises recovering information previously stored in the mass storage data device that is inaccessible to the operating system layer.