Disk device and data management method

• US 10,725,854 B2
• Filed: 09/03/2018
• Issued: 07/28/2020
• Est. Priority Date: 03/20/2018
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation), Toshiba Electronic Devices & Storage Corporation (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Toukairin, Norikatsu
• Primary Examiner(s): Torres, Joseph D
• Application Number:
  US16/120,407
• Publication Number:
  US 20190295595A1
• Time in Patent Office: 694 Days
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 20/1833 by adding special lists or symbols to the coded information G11B20/1806, G11B20/1866 take precedence
• CPC Class Codes: G11B 2020/1222 ECC block, i.e. a block of error correction encoded symbols which includes all parity data needed for decoding
• CPC Class Codes: G11B 2020/1232 sector, i.e. the minimal addressable physical data unit
• CPC Class Codes: G11B 2020/1238 track, i.e. the entire a spirally or concentrically arranged path on which the recording marks are located

Abstract

A disk device includes a disk medium, a magnetic recording head, a processor configured to control the magnetic recording head to write data to and read data from a plurality of tracks of the disk medium on a sector-by-sector basis, and a check value generation circuit configured to generate, for each of the plurality of tracks, check value data based on data stored in one or more sectors of the track. The processor controls the magnetic recording head to write check value data for a first track of the plurality of tracks in a first sector on the disk medium and check value data for a second track of the plurality of tracks in a second sector on the disk medium that is adjacent to the first sector.

Claims

1. A disk device comprising:

a disk medium;

a magnetic recording head;

a processor configured to control the magnetic recording head to write data to and read data from a plurality of tracks of the disk medium on a sector-by-sector basis; and

a check value generation circuit configured to generate, for each of the plurality of tracks, check value data based on data stored in one or more sectors of the track,

wherein the processor controls the magnetic recording head to write check value data for a first track of the plurality of tracks in a first sector on the disk medium and check value data for a second track of the plurality of tracks in a second sector on the disk medium that is adjacent to the first sector, the first and second sectors being disposed in a third track of the plurality of tracks.

2. The disk device of claim 1, wherein

the first sector comprises a first check value sector that stores the check value data for the first track and no check value data for any other track of the plurality of tracks, and

the second sector comprises a second check value sector that stores the check value data for the second track and no check value data for any other track of the plurality of tracks.

3. The disk device of claim 1,

wherein the check value generation circuit generates the check value data for the track by performing XOR operations on the data stored in the one or more sectors of the track.

4. The disk device of claim 1,

wherein the third track includes a plurality of check value sectors and no user data sectors.

5. The disk device of claim 1,

wherein the third track is adjacent to a fourth track that includes a plurality of check value sectors and no user data sectors.

6. The disk device of claim 5,

wherein the third track is adjacent to the fourth track on a first side of the third track and is adjacent to an empty area on a second side of the third track, wherein the empty area separates the third track from a fifth track that includes user data.

7. The disk device according to claim 1,

wherein, when the magnetic recording head writes data to a user data sector of a particular track in the plurality of tracks, the check value generation circuit recalculates check value data for the particular track and the magnetic recording head writes the recalculated check value data in a check value sector of the particular track.

8. A method of data management in a disk device that records data on a disk medium that includes a plurality of tracks, the method comprising:

generating, for each of the plurality of tracks, check value data based on data stored in one or more sectors of the track; and

writing check value data for a first track of the plurality of tracks in a first sector on the disk medium and check value data for a second track of the plurality of tracks in a second sector on the disk medium that is adjacent to the first sector, the first sector and the second sector being disposed in a third track of the plurality of tracks.

9. The method of claim 8, wherein

the first sector comprises a first check value sector that stores the check value data for the first track and no check value data for any other track of the plurality of tracks, and

the second sector comprises a second check value sector that stores the check value data for the second track and no check value data for any other track of the plurality of tracks.

10. The method of claim 8,

wherein the check value data is generated by performing XOR operations on the data stored in the one or more sectors of the track.

11. The method of claim 8,

wherein the third track includes a plurality of check value sectors and no user data sectors.

12. The method of claim 8,

wherein the third track is adjacent to a fourth track that includes a plurality of check value sectors and no user data sectors.

13. The method of claim 12,

wherein the third track is adjacent to the fourth track on a first side of the third track and is adjacent to an empty area on a second side of the third track, wherein the empty area separates the third track from a fifth track that includes user data.

14. The method of claim 8,

wherein when data is written to a user data sector of a particular track in the plurality of tracks, check value data is recalculated for the particular track and the recalculated check value data is written in a check value sector of the particular track.