公开(公告)号：CA1137644A

公开(公告)日：1982-12-14

申请号：CA347544

申请日：1980-03-12

Applicant: IBM

Inventor： HAMMER WILLIAM E ,  LEWIS DAVID O ,  REED JOHN W ,  ROBINSON THOMAS S ,  SLACK KEITH K

IPC: G06F13/00

Abstract: ALLOCATING AND RESOLVING NEXT VIRTUAL PAGES FOR INPUT/OUTPUT In a paged, virtual memory computer system an apparatus is provided for enabling I/O device adapters to request the CPU to allocate or resolve virtual pages into main storage pages as required for I/O data transfers. The I/O adapter provides the channel virtual address information specifying the requested page and channel function information which indicates whether the requested page is to be transferred from secondary storage into main storage or merely allocated as a page in main storage. The channel forms the virtual address information and the channel function information into a page request function event which is stored in an I/O event stack in main storage for retrieval and processing by the CPU. RO9-78-035

公开(公告)号：CA1119308A

公开(公告)日：1982-03-02

申请号：CA334988

申请日：1979-09-04

Applicant: IBM

Inventor： LEWIS DAVID O ,  REED JOHN W ,  WALLIN GARY W

IPC: G06F13/00 ,  G06F13/12 ,  G06F9/46

Abstract: COMMAND QUEUING FOR I/O ADAPTERS In a computer system having: an addressable storage for storing instructions, data and input-output (I/O) commands; a central processing unit (CPU) which fetches and executes instructions; and channel means connecting I/O adapters to the storage and the CPU, an apparatus transfers I/O commands to the I/O adapters whereby the I/O command is either accepted immediately or is queued by the I/O adapter. A queued command is taken up by the I/O adapter when no other data transfer operation is pending. To take up a queued command, the I/O adapter initiates a fetch of the pending command by invoking a standard data-transfer-from-storage sequence. The channel means responds to the fetch initiated by the I/O adapter to send the pending command to the I/O adapter. RO9-78-020