APPARATUS, SYSTEM, AND METHOD FOR ENSURING DATA VALIDITY IN A DATA STORAGE PROCESS

• US 20090150744A1
• Filed: 04/05/2008
• Published: 06/11/2009
• Est. Priority Date: 12/06/2007
• Status: Active Grant

• Current Assignee: Unification Technologies LLC (Acacia Research Corporation)
• Original Assignee: Fusion-IO Incorporated (Western Digital Corporation)
• Inventors: Flynn, David, Thatcher, Jonathan, Strasser, John
• Granted Patent: US 8,316,277 B2
• Time in Patent Office: Days
• US Class Current: 714/752
• CPC Class Codes: G06F 11/1048 using arrangements adapted for a specific error detection or correction feature
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/064 Management of blocks
• CPC Class Codes: G06F 3/0674 Disk device
• CPC Class Codes: G06F 3/0688 Non-volatile semiconductor memory arrays
• CPC Class Codes: G06F 9/52 Program synchronisation; Mutual exclusion, e.g. by means of semaphores
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: H05K 7/1444 Complex or three-dimensional-arrangements; Stepped or dual mother boards

Abstract

An apparatus, system, and method are disclosed for ensuring data validity in a data storage process. A data receiver module receives a storage block and existing parity information. An ECC generation module generates error correcting code (“ECC”) check bits for the data of the storage block in response to receiving the storage block and the existing parity information. The ECC check bits for the storage block are generated using a block code, a convolutional code, etc. A pre-storage consistency module uses the data of the storage block, the existing parity information, and the ECC check bits to determine if the data of the storage block, the existing parity information, and the ECC check bits are consistent. A data storage module stores the data of the storage block and the ECC check bits the data storage device without storing the existing parity information.

Claims

1. An apparatus to extend data protection, the apparatus comprising:

a data receiver module that receives a storage block and existing parity information for the storage block, the storage block comprising data stored together on a data storage device, the storage block comprising at least a portion of one or more data packets, the existing parity information generated for the data of the storage block;

an ECC generation module that generates error correcting code (“

ECC”

) check bits for the data of the storage block in response to the data receiver module receiving the storage block and the existing parity information, wherein the ECC check bits for the storage block are generated using one of a block code and a convolutional code;

a pre-storage consistency module that uses the data of the storage block, the existing parity information, and the ECC check bits to determine if the data of the storage block, the existing parity information, and the ECC check bits are consistent; and

a data storage module that stores the data of the storage block and the ECC check bits for the storage block on the data storage device, wherein the existing parity information for the storage block is not stored on the data storage device.

2. The apparatus of claim 1, wherein the pre-storage consistency module is independent of the ECC generation module.

3. The apparatus of claim 2, further comprising an ECC check bit parity module that uses the ECC check bits to generate ECC check bit parity information and wherein the pre-storage consistency module uses the ECC check bit parity information to determine consistency.

4. The apparatus of claim 3, wherein the pre-storage consistency module uses the data of the storage block and the existing parity information in a function independent from the ECC generation module and the ECC check bit parity module to generate alternate parity information that is checked against the ECC check bit parity information to determine consistency.

5. The apparatus of claim 1, further comprising:

a data retriever module that retrieves a storage block with data from one or more data packets stored on the data storage device and ECC check bits for the storage block in response to a read request;

a parity generation module that generates parity information for the data of the retrieved storage block and for the ECC check bits;

an ECC detection module that uses the ECC check bits stored in conjunction with the storage block to generate an ECC syndrome to determine if the data of the retrieved storage block and the generated parity has an error; and

a post-storage consistency module that uses the data from the retrieved storage block, the generated parity information generated by the parity generation module, and the ECC syndrome to determine if the data, generated parity information, and the ECC syndrome are consistent.

6. The apparatus of claim 5, further comprising an ECC correction module that corrects one or more errors in the data of the storage block and updates one or more of parity bits in response to the ECC detection module determining that the data of the retrieved storage block and the generated parity has an error.

7. The apparatus of claim 5, wherein the post-storage consistency module is independent of the ECC detection module.

8. The apparatus of claim 7, further comprising an ECC syndrome parity module that uses the ECC syndrome to generate ECC syndrome parity information and wherein the post-storage consistency module uses the ECC syndrome parity information to determine consistency.

9. The apparatus of claim 8, wherein the post-storage consistency module uses the data of the retrieved storage block and the generated parity information in a function independent from the ECC detection module and the ECC syndrome parity module to generate alternate parity information that is checked against the ECC syndrome parity information to determine consistency.

10. The apparatus of claim 5, further comprising a post-retrieval parity check module that checks parity of the retrieved storage block and the ECC check bits using the generated parity information from the retrieved storage block and ECC check bits in response to the ECC detection module completing determining if the data of the retrieved storage block has an error.

11. The apparatus of claim 1, wherein the ECC generation module further comprises generating an error checking code for the existing parity information of the storage block, the error checking code stored with the ECC check bits for the storage block.

12. The apparatus of claim 11, wherein the error checking code for the existing parity information comprises one of parity check bits, check code, and ECC check bits.

13. The apparatus of claim 1, wherein the ECC generation module further comprises generating ECC check bits for the data of the storage block combined with the existing parity information such that the generated ECC check bits do not distinguish between data and parity information.

14. The apparatus of claim 1, further comprising a pre-storage parity check module that checks parity of the data of the storage block received by the data receiver module using the existing parity information and the parity of the ECC check bits, wherein the parity check module checks parity prior to the data storage module storing the storage block and ECC check bits.

15. The apparatus of claim 1, wherein a data packet comprises at least a portion of a data segment received in conjunction with a storage request and further comprising a decoding module that decodes data of the data segment, resulting in parity and un-encoded data of the data segment, in a single process step such that there is no gap in error detection capability.

16. The apparatus of claim 1, wherein a data packet comprises at least a portion of a data segment received in conjunction with a storage request and further comprising a parity consistency module that maintains no gap in error detection capability by using parity information for the data of the data segment from the decoding module generating the parity until the data receiver module receives the parity and the data in the form of the storage block, wherein the parity consistency module maintains parity through at least one of encrypting the data, compressing the data, and a user-defined, application-specific function.

17. The apparatus of claim 1, wherein the ECC check bits for the storage block are generated using one of a BCH code, Reed-Solomon code, and a turbo code.

18. The apparatus of claim 1, wherein the data storage module does not store parity at information of the ECC check bits.

19. A system to extend data protection, the system comprising:

a data storage device;

a storage controller that controls storage of data in the data storage device;

a data receiver module that receives a storage block and existing parity information for the storage block, the storage block comprising data stored together on the data storage device, the storage block comprising at least a portion of one or more data packets, the existing parity information generated for the data of the storage block;

an ECC generation module that generates error correcting code (“

ECC”

) check bits for the data of the storage block in response to the data receiver module receiving the storage block and the existing parity information, wherein the ECC check bits for the storage block are generated using one of a block code and a convolutional code;

a pre-storage consistency module that uses the data of the storage block, the existing parity information, and the ECC check bits to determine if the data of the storage block, the existing parity information, and the ECC check bits are consistent; and

a data storage module that stores the data of the storage block and the ECC check bits for the storage block on the data storage device in response to the pre-storage consistency module determining that the data of the storage block, the existing parity information, and the ECC check bits are consistent, wherein the existing parity information for the storage block is not stored on the data storage device.

20. The system of claim 19, further comprising one or more system buses and networks, the storage controller receiving a data segment from one of a CPU and a memory over at least one of a system bus and a network, the data segment comprising the data of the one or more data packets, wherein the data segment is received in conjunction with a storage request to store the data segment.

21. The system of claim 19, further comprising an overall consistency module that maintains protection of the data with no gap in error detection capability from receipt of the data by the system until the data storage module stores the data of the data segment, wherein the overall consistency module further comprises a sub-module associated with each transition from one data protection scheme to another.

22. The apparatus of claim 21, wherein the overall consistency module further comprises a decoding module that decodes data of the data segment, resulting in parity and un-encoded data of the data segment, in a single process step such that there is no gap in error detection capability from when the data is in an encoded form to when the data includes parity information.

23. The apparatus of claim 21, wherein the overall consistency module further comprises an encoding module that encodes data of the data segment protected with parity information, resulting in encoded data of the data segment, in a single process step such that there is no gap in error detection capability from when the data includes parity information to when the data is in an encoded form.

24. The apparatus of claim 21, wherein the overall consistency module further comprises a parity consistency module that maintains no gap in error detection capability by using parity information for the data of the data segment from when parity information is generated for the data of the data segment until the data receiver module receives the existing parity information and the data in the form of the storage block, and from when the data retriever module retrieves the storage block and the parity generation module generates parity information for the data until the data protected using parity information is encoded by an encoding module that encodes data of the data segment, wherein the parity consistency module maintains parity through at least one of encrypting the data, compressing the data, decrypting the data, decompressing the data, and a user-defined, application-specific function.

25. The apparatus of claim 21, wherein the system further comprises at least one of a CPU and a memory from which the storage controller receives the data segment.

26. The apparatus of claim 21, wherein the overall consistency module further maintains protection of the data with no gap in error detection capability from when the data is retrieved from the data storage device until the data is delivered from the system.

27. A computer program product comprising a computer readable medium having computer usable program code executable to perform operations for extending data protection, the operations of the computer program product comprising:

receiving a storage block and existing parity information for the storage block, the storage block comprising data stored together on a data storage device, the storage block comprising at least a portion of one or more data packets, the existing parity information generated for the data of the storage block;

generating error correcting code (“

ECC”

) check bits for the data of the storage block in response to receiving the storage block and the existing parity information, wherein the ECC check bits for the storage block are generated using one of a block code and a convolutional code;

using the data of the storage block, the existing parity information, and the ECC check bits to determine if the data of the storage block, the existing parity information, and the ECC check bits are consistent; and

storing the data of the storage block and the ECC check bits for the storage block on the data storage device in response to determining that the data of the storage block, the existing parity information, and the ECC check bits are consistent, wherein the existing parity information for the storage block is not stored on the data storage device.