Method of managing a solid state drive, associated systems and implementations

• US 8,327,066 B2
• Filed: 09/29/2009
• Issued: 12/04/2012
• Est. Priority Date: 09/30/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Heo, Jin Gyu, Lee, Donggi, Hwang, Seongsik, Lee, Dongjin, Lee, Jeong Woo, Cheon, Wonmoon, Lim, Seungho, Kim, Jong-Min, Lee, Haeri, Jee, Woonhyug, Lee, Jae-Hwa
• Primary Examiner(s): DUDEK JR, EDWARD J
• Application Number:
  US12/585,935
• Publication Number:
  US 20100082890A1
• Time in Patent Office: 1,162 Days
• Field of Search: 711/103, 711/112, 711/170, 711/E12.008, 713/100, 714/6.13
• US Class Current: 711/103
• CPC Class Codes: G06F 12/0246 in block erasable memory, e.g. flash memory
• CPC Class Codes: G06F 13/1673 using buffers
• CPC Class Codes: G06F 2212/7201 Logical to physical mapping or translation of blocks or pages
• CPC Class Codes: G06F 9/4403 Processor initialisation
• CPC Class Codes: G06F 9/4406 Loading of operating system
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A solid state drive may include one or more memory cell arrays divided into a plurality of blocks. A first portion of the blocks may be designated for storing user data and a second portion of the blocks may be designated as reserved blocks for replacing defective blocks in the first portion. In one embodiment, the method includes reformatting, by a memory controller, the solid state drive to convert one or more blocks in the first portion into reserved blocks.

Claims

1. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation through a plurality of channels with respect to the first portion; and

selectively reformatting, by the memory controller, the solid state drive to convert one or more blocks in the first portion into reserved blocks, the selectively reformatting including a host accessing the solid state drive interpreting a size of the first portion as being unchanged.

2. The method of claim 1, further comprising:

first determining, at the memory controller, if a number of available reserved blocks in the solid state drive is less than a threshold number, an available reserved block being a reserved block available to replace a block in the first portion; and

wherein

the reformatting step reformats the solid state drive to convert one or more blocks in the first portion into reserved blocks if the first determining step determines the number of available reserved blocks in the solid state drive is less than the threshold number.

3. The method of claim 2, further comprising:

second determining if sufficient available space exists in the first portion to permit reformatting the solid state drive if the first determining step determines the number of available reserved blocks in the solid state drive is less than a threshold number; and

wherein

the reformatting step reformats the solid state drive to convert one or more blocks in the first portion into available reserved blocks if (1) the first determining step determines the number of available reserved blocks in the solid state drive is less than a threshold number and (2) the second determining step determines sufficient available space exists in the first portion to permit reformatting the solid state drive.

4. The method of claim 3, wherein the second determining step determines whether a sufficient number of free blocks exist and can be created in the first portion such that if converted to available reserved blocks the number of available reserved blocks will exceed the threshold number.

5. The method of claim 4, wherein the reserved blocks are distributed among a plurality of memory chips in the solid state drive.

6. The method of claim 5, further comprising:

loading code data from at least one of the plurality of memory chips to a random access memory to manage the solid state drive.

7. The method of claim 3, further comprising:

downloading firmware for backing up data on the solid state drive if the second determining step determines insufficient available space exists in the first portion to permit reformatting the solid state drive.

8. The method of claim 3, further comprising:

backing up data on the solid state drive if the second determining step determines insufficient available space exists in the first portion to permit reformatting the solid state drive.

9. The method of claim 1, wherein the reformatting step comprises:

filling, at least partially, at least one block in the first portion by moving valid data portions from partially valid blocks in the first portion;

creating free blocks from the partially valid blocks by erasing the partially valid blocks; and

converting at least one of the created free blocks to an available reserved block.

11. The method of claim 1, wherein the reformatting step comprises:

converting at least one free block in the first portion to an available reserved block.

13. The method of claim 1, wherein the reformatting step comprises:

converting at least one invalid block storing invalid data to a free block; and

converting at least one of the created free blocks to an available reserved block.

15. The method of claim 1, further comprising:

updating status information for the solid state drive based on the reformatting step.

16. The method of claim 15, further comprising:

determining a status state of the solid state drive based on the status information, the status state being one of a good state, an intermediate state and a bad state, the intermediate state being between the good state and the bad state.

17. The method of claim 16, further comprising:

indicating the determined status state.

10. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation through a plurality of channels with respect to the first portion; and

selectively reformatting, by the memory controller, the solid state drive to convert one or more blocks in the first portion into reserved blocks, wherein the selectively reformatting includes,

filling, at least partially, at least one block in the first portion by moving valid data portions from partially valid blocks in the first portion,

creating free blocks from the partially valid blocks by erasing the partially valid blocks, and

setting at least one of the created free blocks to a hybrid state, the hybrid state being recognized as a bad block by a host accessing the solid state drive and being recognized as an available reserved block by the solid state drive such that the host interprets a size of the first portion as being unchanged.

12. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation through a plurality of channels with respect to the first portion; and

selectively reformatting, by the memory controller, the solid state drive to convert one or more blocks in the first portion into reserved blocks, wherein the selectively reformatting includes,

setting at least one free block in the first portion to a hybrid state, the hybrid state being recognized as a bad block by a host accessing the solid state drive and being recognized as an available reserved block by the solid state drive such that the host interprets a size of the first portion as being unchanged.

14. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation through a plurality of channels with respect to the first portion; and

selectively reformatting, by the memory controller, the solid state drive to convert one or more blocks in the first portion into reserved blocks, wherein the selectively reformatting includes,

converting at least one invalid block storing invalid data to a free block, and

setting at least one of the created free blocks to a hybrid state, the hybrid state being recognized as a bad block by a host accessing the solid state drive and being recognized as an available reserved block by the solid state drive such that the host interprets a size of the first portion as being unchanged.

18. A system, comprising:

a memory device including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion; and

a memory controller configured to manage reading and writing through a plurality of channels from the first portion and configured to selectively change one or more blocks in the first portion to reserved blocks, wherein a host drive interprets a size of the first portion as being unchanged when accessing the solid state drive.

19. The system of claim 18, wherein the memory controller is configured to determine if a number of available reserved blocks in the memory device is less than a threshold number, an available reserved block being a reserved block available to replace a block in the first portion, and the memory controller is configured to change one or more blocks in the first portion into reserved blocks if the number of available reserved blocks in the solid state drive is less than the threshold number.

20. The system of claim 19, wherein the memory controller is configured to receive information on the number of available reserved blocks from a status checking module.

21. The system of claim 18, wherein the memory controller is configured to remove an association of at least one block address with the first portion to change one or more blocks in the first portion into reserved blocks.

22. The system of claim 18, wherein the memory controller is configured to change an association of at least one block address from the first portion to the second portion to change one or more blocks in the first portion into reserved blocks.

23. The system of claim 18, wherein the memory controller is configured to change an indicator associated with at least one block address in an address translation table to change one or more blocks in the first portion into reserved blocks.

24. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation through a plurality of channels with respect to the first portion; and

selectively increasing, by the memory controller, a number of available reserved blocks in the solid state drive, an available reserved block being a reserved block available to replace a block in the first portion, the selectively increasing including a host accessing the solid state drive interpreting a size of the first portion as being unchanged.

25. The method of claim 24, wherein the increasing step decreases a number of blocks in the first portion.

26. The method of claim 24, wherein the increasing step does not decrease the number of blocks in the first portion.

27. The method of claim 24, wherein the increasing step increases the number of available reserved blocks to at least a desired number.

28. A method of managing a solid state drive, the solid state drive including one or more memory cell arrays divided into a plurality of blocks, a first portion of the blocks designated for storing user data and a second portion of the blocks being designated as reserved blocks for replacing defective blocks in the first portion, the method comprising:

performing, by a memory controller, one of at least one read operation and at least one write operation with respect to the first portion; and

selectively setting, by the memory controller, at least one block in the first portion to a hybrid state, the hybrid state being recognized as a bad block by a host accessing the solid state drive and being recognized as an available reserved block by the solid state drive such that the host interprets a size of the first portion as being unchanged, an available reserved block being a reserved block available to replace a block in the first portion.

29. The method of claim 28, wherein the setting step sets an indicator associated with the at least one block in a flash translation layer of a memory controller to indicate the hybrid state.