Zone-based defragmentation methods and user devices using the same

1. A defragmentation method for a user device including a host and a nonvolatile storage device, the method comprising:

determining whether fragments of a first file stored at the nonvolatile storage device are in a same logical address zone;

determining, if the fragments of the first file are in different logical address zones, that usable space is available in at least one of the different logical address zones; and

executing defragmentation of the fragments of the first file if the fragments of the first file are in the different logical address zones by moving the fragments of the first file to a logical address space corresponding to the at least one of the different logical address zones.

2. The defragmentation method of claim 1 , further comprising:

skipping defragmentation of the fragments of the first file when the fragments of the first file are in the same logical address zone.

3. The defragmentation method of claim 1 , wherein the executing defragmentation of the fragments of the first file comprises:

sending read and write commands for each of the fragments of the first file from the host to the nonvolatile storage device.

4. The defragmentation method of claim 1 , wherein the executing defragmentation of the fragments of the first file comprises:

sending a series of defrag commands from the host to the nonvolatile storage device.

5. The defragmentation method of claim 4 , wherein each of the defrag commands uses a read/write command including defragmentation and end of defragmentation information.

6. The defragmentation method of claim 4 , wherein the executing defragmentation further comprises:

classifying the series of defrag commands according to logical address zone; and

moving the fragments of the first file to logical address spaces corresponding to logical address zones based on the classified series of defrag commands.

7. The defragmentation method of claim 6 , further comprising:

setting a physical block storing invalid data generated during the executing of defragmentation on the fragments of the first file to an invalid block without additional information from the host.

8. The defragmentation method of claim 1 , further comprising:

determining whether rearrangement of fragments of the defragmented file is required after defragmentation on the fragments of the first file is completed; and

rearranging the fragments of the defragmented file if rearrangement of the fragments of the defragmented file is required.

9. The defragmentation method of claim 8 , wherein the rearranging the fragments of the defragmented file comprises:

issuing, by the host to the nonvolatile storage device, an LBA (logical block address) command including source and destination addresses for fragments of the defragmented file to be rearranged; and

changing mapping information of the defragmented file without physical movement of the fragments of the defragmented file.

10. A user device, comprising:

a host including a defragmentation program; and

a memory controller configured to control a storage medium in response to a request from the host;

wherein a logical address space managed by the host is divided into a plurality of logical address zones, each of the plurality of logical address zones including logical addresses associated with physical addresses of the storage medium; and

wherein the host is configured to skip defragmentation of a fragmented file stored at a same logical address zone and to perform logical defragmentation of a fragmented file stored at different logical address zones.

11. The user device of claim 10 , wherein the host is configured to

determine that usable space is available in at least one of the different logical address zones; and

send read and write commands for each fragment of the fragmented file to the memory controller for defragmentation of the fragments of the fragmented file.

12. The user device of claim 10 , wherein the host is configured to

determine that usable space is available in at least one of the different logical address zones; and

send a series of defrag commands to the memory controller for performing defragmentation of fragments of the fragmented file.

13. The user device of claim 12 , wherein each of the defrag commands uses a read/write command including defragmentation and end of defragmentation information.

14. The user device of claim 13 , wherein the memory controller is configured to classify the series of defrag commands according to logical address zone, and to move fragments of the fragmented file to logical address spaces corresponding to logical address zones based on the classified series of defrag commands.

15. The user device of claim 10 , wherein the host is further configured to determine whether rearrangement of fragments of the defragmented file is required after defragmentation of the fragmented file is completed, and issue, to the memory controller, an LBA (logical block address) command including source and destination addresses for fragments to be rearranged if rearrangement of the fragments of the defragmented file is required, and wherein the memory controller is configured to rearrange the fragments of the defragmented file by changing mapping information of the defragmented file without physical movement of the fragments of the defragmented file.

16. A file defragmentation method for a user device including a host and a nonvolatile storage medium, the method comprising:

selectively defragmenting, by the host, a fragmented file stored in the nonvolatile storage medium based on whether fragments of the fragmented file are associated with a same logical address zone in a logical address space corresponding to a physical address space of the nonvolatile storage medium, the logical address space including a plurality of logical address zones, and each of the plurality of logical address zones including a plurality of continuous logical addresses.

17. The method of claim 16 , wherein the selectively defragmenting comprises:

skipping defragmentation of the fragmented file if the fragments of the fragmented file are associated with the same logical address zone.

18. The method of claim 16 , further comprising:

determining that usable space is available in a logical address zone among the plurality of logical address zones; and

wherein the selectively defragmenting includes

defragmenting the fragmented file by moving the fragments of the fragmented file such that the fragments of the fragmented file are associated with only the logical address zone among the plurality of logical address zones.

19. The method of claim 16 , wherein the selectively defragmenting comprises:

defragmenting the fragmented file only if the fragments of fragmented file are associated with different logical address zones.

20. The method of claim 16 , wherein fragments of the defragmented file are associated with the same logical address zone, and wherein the method further includes,

rearranging the fragments of the defragmented file by changing mapping information of the defragmented file without physical movement of the fragments of the defragmented file in the physical address space of the nonvolatile storage medium.