Apparatus and methods using invalidity indicators for buffered memory

• US 20060136676A1
• Filed: 09/20/2005
• Published: 06/22/2006
• Est. Priority Date: 12/21/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Park, Chan-Ik, Jung, Tae-Sung, Kook, Kyun-Ho, Min, Sang Lyul
• Granted Patent: US 7,802,054 B2
• Time in Patent Office: Days
• US Class Current: 711/144
• CPC Class Codes: G06F 3/0616 in relation to life time, e.g. increasing Mean Time Between Failures [MTBF]
• CPC Class Codes: G06F 3/0625 Power saving in storage systems
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/0679 Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP]
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A storage system includes a storage medium configured to store data and a buffer memory configured to buffer data to be written to the storage medium. The storage system further includes a controller configured to selectively transfer the buffered data to the storage medium responsive to an invalidity indicator received from an external source. For example, the invalidity indicator may comprise unwrite information received from an external source, e.g., information that indicates that selected buffered data corresponds to deleted file data.

Claims

1. A storage system, comprising:

a storage medium configured to store data;

a buffer memory configured to buffer data to be written to the storage medium; and

a controller configured to selectively transfer the buffered data to the storage medium responsive to an invalidity indicator received from an external source.

2. The storage system of claim 1, wherein the invalidity indicator comprises unwrite information.

3. The storage system of claim 2, wherein the unwrite information indicates that selected buffered data corresponds to deleted file data.

4. The storage system of claim 1, wherein the controller is configured to invalidate selected buffered data responsive to the invalidity indicator.

5. The storage system of claim 4, wherein the controller is configured to store write state information indicative of invalidity of the invalidated buffered data responsive to the invalidity indicator and to prevent transfer of the invalidated buffered data from the buffer memory to the storage medium responsive to the stored write state information.

6. The storage system of claim 5, wherein the controller is configured to trigger a transcribe operation responsive to a storage limitation in the buffer memory and/or an idle state of the storage medium, wherein the transcribe operation comprises transferring valid buffered data from the buffer memory to the storage medium controller while foregoing transfer of the invalidated buffered data from the buffer memory to the storage medium.

7. The storage system of claim 4, wherein the controller is further configured to enable reuse of storage space in the buffer memory occupied by the invalidated buffered data responsive to the invalidation of the invalidated buffered data.

8. The storage system of claim 1, wherein the buffer memory comprises nonvolatile and/or volatile semiconductor memory, and wherein the storage medium comprises nonvolatile semiconductor memory and/or a magnetic storage medium.

9. A computing system, comprising:

a storage system comprising a storage medium configured to store data, a buffer memory configured to buffer data to be written to the storage medium and a controller configured to selectively transfer the buffered data to the storage medium responsive to an invalidity indicator; and

a host configured to transfer the data to the buffer memory and to provide the invalidity indicator to the storage system responsive to a data modification operation at the host.

10. The computing system of claim 9, wherein the invalidity indicator comprises an unwrite command.

11. The computing system of claim 10, wherein the host is configured to generate the unwrite command responsive to deletion of file data.

12. The computing system of claim 9, wherein the controller is configured to invalidate selected buffered data responsive to the invalidity indicator.

13. The computing system of claim 12, wherein the controller is configured to store write state information indicative of invalidity of the invalidated buffered data responsive to the invalidity indicator and to prevent transfer of the invalidated buffered data from the buffer memory to the storage medium responsive to the stored write state information.

14. The computing system of claim 13, wherein the controller is configured to trigger a transcribe operation responsive to a storage limitation in the buffer memory and/or an idle state of the storage medium, wherein the transcribe operation comprises transferring valid buffered data from the buffer memory to the storage medium controller while foregoing transfer of the invalidated buffered data from the buffer memory to the storage medium.

15. The computing system of claim 12, wherein the controller is further configured to enable reuse of storage space in the buffer memory occupied by the invalidated buffered data responsive to the invalidation of the invalidated buffered data.

16. The computing system of claim 9, wherein the buffer memory comprises nonvolatile and/or volatile semiconductor memory, and wherein the storage medium comprises nonvolatile semiconductor memory and/or a magnetic storage medium.

17. A method of operating a storage system including a storage medium and a buffer memory configured to store data to be written to the storage medium, the method comprising:

receiving a invalidity indicator related to data stored in the buffer memory from an external source; and

selectively transferring data stored in the buffer memory to the storage medium responsive to the received invalidity indicator.

18. The method of claim 17, wherein the invalidity indicator comprises unwrite information.

19. The method of claim 18, wherein the unwrite information indicates that selected data stored in the buffer memory corresponds to deleted file data.

20. The method of claim 17, wherein selectively transferring data stored in the buffer memory to the storage medium responsive to the received invalidity indicator comprises:

invalidating selected data stored in the buffer memory responsive to the invalidity indicator; and

preventing transfer of the invalidated data from the buffer memory to the storage medium.

21. The method of claim 20:

wherein invalidating selected data stored in the buffer memory responsive to the invalidity indicator comprises storing write state information indicative of invalidity of the invalidated data responsive to the invalidity indicator; and

wherein preventing transfer of the invalidated data from the buffer memory to the storage medium comprises preventing transfer of data from the buffer memory to the storage medium responsive to the stored write state information.

22. The method of claim 20, further comprising performing a transcribe operation responsive to a storage limitation in the buffer memory and/or an idle state of the storage medium, wherein the transcribe operation comprises transferring valid data from the buffer memory to the storage medium controller while foregoing transfer of the invalidated data from the buffer memory to the storage medium.

23. The method of claim 20, further comprising enabling reuse of storage space in the buffer memory occupied by the invalidated data responsive to the invalidation of the invalidated data.

24. The method of claim 17, wherein the buffer memory comprises nonvolatile and/or volatile semiconductor memory, and wherein the storage medium comprises nonvolatile semiconductor memory and/or a magnetic storage medium.

25. A system for controlling data storage in a storage medium, the system comprising:

a buffer memory configured to buffer data to be written to the storage medium; and

a controller configured to selectively transfer the buffered data to the storage medium responsive to an invalidity indicator received from an external source.

26. The system of claim 25, wherein the invalidity indicator comprises unwrite information.

27. The system of claim 26, wherein the unwrite information indicates that selected buffered data corresponds to a deleted file.

28. The system of claim 25, wherein the controller is configured to invalidate selected buffered data responsive to the invalidity indicator.

29. The system of claim 28, wherein the controller is configured to store write state information indicative of invalidity of the invalidated buffered data responsive to the invalidity indicator and to prevent transfer of the invalidated buffered data from the buffer memory to the storage medium responsive to the stored write state information.

30. The system of claim 29, wherein the controller is configured to trigger a transcribe operation responsive to a storage limitation in the buffer memory and/or an idle state of the storage medium, wherein the transcribe operation comprises transferring valid buffered data from the buffer memory to the storage medium controller while foregoing transfer of the invalidated buffered data from the buffer memory to the storage medium.

31. The system of claim 28, wherein the controller is further configured to enable reuse of storage space in the buffer memory occupied by the invalidated buffered data responsive to the invalidation of the invalidated buffered data.

32. The system of claim 25, wherein the buffer memory comprises nonvolatile and/or volatile semiconductor memory.

33. The system of claim 25, wherein the buffer memory includes at least two volatile memories having different read/write functionality.