US 12,033,662 B2
Magnetic disk device
Kana Furuhashi, Kawasaki Kanagawa (JP); and Hiroyuki Takeda, Tokyo (JP)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (JP); and Toshiba Electronic Devices & Storage Corporation, Tokyo (JP)
Filed by KABUSHIKI KAISHA TOSHIBA, Tokyo (JP); and TOSHIBA ELECTRONIC DEVICES & STORAGE CORPORATION, Tokyo (JP)
Filed on Aug. 31, 2021, as Appl. No. 17/462,379.
Claims priority of application No. 2021-044666 (JP), filed on Mar. 18, 2021.
Prior Publication US 2022/0301590 A1, Sep. 22, 2022
Int. Cl. G11B 20/18 (2006.01); G11B 20/12 (2006.01)
CPC G11B 20/1889 (2013.01) [G11B 20/1258 (2013.01); G11B 20/1833 (2013.01); G11B 20/1866 (2013.01); G11B 2020/1222 (2013.01); G11B 2020/1232 (2013.01); G11B 2020/1238 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A magnetic disk device comprising:
a disk including a media cache and a plurality of sectors, that include sectors of a first track having a first parity sector, and sectors of a second track having a second parity sector;
a head configured to write data on the disk and read data from the disk; and
a controller configured to:
detect error sectors among the plurality of the sectors and record information about the error sectors in a memory device; and
upon receiving a write command to write first data in a first region of the first track, which is a portion of the first track, determine from the information recorded in the memory device whether the first track includes one or more of the error sectors, and in response to determining that the first track includes one or more of the error sectors, (i) perform a first XOR operation on all sectors of the first track other than one or more sectors of the first region and the first parity sector of the first track, and then, (ii) write the first data in the one or more sectors of the first region, perform a second XOR operation on the one or more sectors of the first region and the result of the first XOR operation, and write the result of the second XOR operation in the first parity sector.