公开(公告)号：DE3851928T2

公开(公告)日：1995-04-20

申请号：DE3851928

申请日：1988-08-04

Applicant: IBM

Inventor： CROCKETT ROBERT NELSON ,  KERN ROBERT FREDERICK ,  MILLER ARNOLD GRANT ,  NORRIS RICHARD ERNEST ,  POUSSON MICHAEL WILLIAM ,  WAGNER ROBERT E

IPC: G06F13/14 ,  G06F11/20 ,  G06F13/10 ,  G06F13/12 ,  G06F15/16 ,  G06F15/177

Abstract: A plurality of host processors share access to a peripheral data storage sub-system and each have program means for controlling asynchronous operations of the sub-system. Control blocks in each of the host processors are addressably linked together for enabling inferred access to a unit control block (UCB) for any of a plurality of peripheral devices in the sub-system. The sub-system selectively groups some of the devices such that only devices designated as primary devices are addressably accessible by host processor application programs. Other devices in the respective groups are secondary devices and are accessed by the sub-system whenever the primary device in the same group cannot perform a host processor commanded operation. Means are provided for identifying the secondary devices to all of the host processors.

公开(公告)号：DE3851928D1

公开(公告)日：1994-12-01

申请号：DE3851928

申请日：1988-08-04

Applicant: IBM

Inventor： CROCKETT ROBERT NELSON ,  KERN ROBERT FREDERICK ,  MILLER ARNOLD GRANT ,  NORRIS RICHARD ERNEST ,  POUSSON MICHAEL WILLIAM ,  WAGNER ROBERT E

IPC: G06F13/14 ,  G06F11/20 ,  G06F13/10 ,  G06F13/12 ,  G06F15/16 ,  G06F15/177

Abstract: A plurality of host processors share access to a peripheral data storage sub-system and each have program means for controlling asynchronous operations of the sub-system. Control blocks in each of the host processors are addressably linked together for enabling inferred access to a unit control block (UCB) for any of a plurality of peripheral devices in the sub-system. The sub-system selectively groups some of the devices such that only devices designated as primary devices are addressably accessible by host processor application programs. Other devices in the respective groups are secondary devices and are accessed by the sub-system whenever the primary device in the same group cannot perform a host processor commanded operation. Means are provided for identifying the secondary devices to all of the host processors.