I/O cache controller containing a buffer memory partitioned into lines accessible by corresponding I/O devices and a directory to track the lines

摘要

A cache for use with input/output devices attached to an input/output bus. Requests for access to system memory by an input/output device pass through the cache. Access authority is checked to determine whether an input/output device is authorized to access that particular page. If it is not, access is denied. Each input/output device has access to a portion of the cache, so that activity by one device will not interfere with activity by another.