Method and apparatus for consolidated buffer handling for computer device input/output

摘要

A computer has a device driver and an operating system that call a consolidated buffer service routine to coordinate the transfer of data between a main memory and an external device. The consolidated buffer service routine includes a memory preparation service routine and a memory checking service routine. The memory preparation service routine coordinates data transfers between the external device and the memory with the operating system and a data cache, and with other data transfers. The memory preparation service routine ensures that the buffer remains assigned to the memory ranges until the memory checking service routine relinquishes the buffer. Before calling the memory preparation service routine, and I/O preparation table is set which defines the addresses and the type of addresses of the buffer, the size of the data to be transferred, the page size of the buffer, and flags defining data flow and type.