The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 22, 2004
Filed:
Apr. 27, 2001
Bruce Leroy Beukema, Hayfield, MN (US);
Richard Charles Booth, San Jose, CA (US);
David Robert Engebretsen, Cannon Falls, MN (US);
Thomas Rembert Sand, Rochester, MN (US);
Kenneth Michael Valk, Rochester, MN (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A clustered computer system, bridge device and method include support for an atomic ownership change operation that ensures orderly and reliable ownership management of an input/output (I/O) bridge device. A lock indicator is associated with a bridge device, and is used to indicate a “locked” or “unlocked” status of the bridge device. Whenever the lock indicator indicates that the bridge device is unlocked, an atomic operation such as a read request to a lock indicator register is utilized to both set the indicator to indicate a locked status for the bridge device, and to associate the bridge device with a source node that initiated the atomic operation. In connection with the lock indicator, write access to one or more configuration parameter registers is controlled such that only the node that is associated with the bridge device is permitted to update such configuration parameter registers.