Loading patent…
AssigneeInternational Business Machines Corporation
InventorsJeff J. Dobbek, Steven Robert Hetzler
Estimating the term…
A data recording disk drive includes a system and method for mapping around skip sectors, both bad sectors and spare sectors. A received logical block address is converted to a corresponding physical block address by mapping through a set of tables. A first table includes entries for virtual tracks which group together LBAs having shared high order bits. A second table contains entries for the skip sectors. The high order bits of a given LBA are used to select an entry in the first table, which entry is an index into the second table. Starting from the index point, the second table is searched, using the low order bits of the LBA, for a skip sector beyond the LBA value. Once the appropriate skip sector is found, the index of this skip sector within the second table is added to the LBA to compute the PBA. The PBA is then mapped to a zone, cylinder, head, sector location on the disk drive. The mapping system reduces the total storage required to convert LBAs to ZCHS values and improves the performance of the conversion process. Additional features include a third table for distinguishing bad sectors from spare sectors, schema for re-mapping spare sectors to substitute for data sectors which fail during use, and overlap between the LBA high order and low order bits to further improve performance.
In a disk drive having a data recording disk with radially spaced tracks and circumferentially spaced sectors and a head capable of reading information from the data recording disk, a method for converting a logical address to a physical address, comprising the steps of:
In a disk drive having a data recording disk with radially spaced tracks and circumferentially spaced sectors, a hierarchical sector map for mapping out skip sectors, the hierarchical sector map having entries arranged in groups according to shared logical address bits, wherein an index value associated with each entry represents an offset from a physical location on said disk, the groups having at least some of the shared bits omitted from the entries, wherein the groups are indexed from a higher level in the hierarchy according to at least some of the shared logical address bits, wherein a high order portion of a logical address specified in a data request received by the disk drive is used to select an entry in the higher level of the hierarchy, wherein a low order portion of the specified logical address is used to search within the lower level of the hierarchy, wherein the low order portion of the specified logical address overlaps the high order portion of the logical address.
In a disk drive having a data recording disk with radially spaced tracks and circumferentially spaced sectors, a system for mapping logical block addresses around skip sectors, the logical block addresses having logical address bits, comprising:
In a disk drive having a data recording disk with radially spaced tracks and circumferentially spaced sectors and a head capable of reading information from the data recording disk, a method for converting a logical address to a physical address, comprising the steps of:
Dependencies are inferred from the claim text.