Trinh D Bui

US Patent:

59639776, Oct 5, 1999

Filed:

Oct 9, 1997

Appl. No.:

8/947213

Inventors:

Clifford M. Gold - Fremont CA
Hang D. Nguyen - Fremont CA
George Li - Santa Clara CA
Minnie Uppuluri - San Jose CA
Hoa Luong - Fremont CA
Steve Paul - Santa Cruz CA
Bryan Mee - San Jose CA
Trinh Bui - San Jose CA

Assignee:

Quantum Corporation - Milpitas CA

International Classification:

G06F 1200

US Classification:

711156

Abstract:

A method of coordinating access to a data buffer including a plurality of data blocks, using a buffer list with a plurality of entries corresponding to the data blocks. Each buffer list entry includes: (i) a status code for indicating the status of data in the corresponding data block, and (ii) a partial address common to both the next buffer list entry and a data block corresponding to said next buffer list entry. A status code is selected from a cyclical set of sequential status codes having a period of N, the status codes sequentially, and alternately, representing the most recent history of a data block, including: (i) full status, indicating data in the data block has been retrieved from the storage device or is to be stored to the storage device, or (ii) empty status, indicating data transferred out of the data block to a host or to the storage device. A store flag maintains a status code representing empty status, and a retrieve flag maintains a status code representing full status. When storing data into the data buffer, locating a desired buffer list entry list with an empty status code by traversing the buffer list, calculating the address of each entry using the partial address in the previous entry, until the desired entry is found.