Method and apparatus for updating data in mass storage subsystem using emulated shared memory

摘要

A method and apparatus is disclosed wherein a first structure in a memory of a controller for sharing information is defined and a hidden structure containing control information for sharing information with the first defined structure is created. Data is synchronized between controllers so that firmware development is simplified. The user defines a structure and through the use of macro calls makes that structure shared. Lock rules are provided, to perform synchronization and buffer management. Failover and failback are also addressed to provide a comprehensive solution for sharing work and information between controllers. Accordingly, the emulated shared memory mechanism allows a programmer to define a structure that contains information for sharing without having to reinvent firmware when new features are added to a storage controller.