US 5,430,845 A · Peripheral device interface for dynamically selecting boot disk device driver

Abstract

A common peripheral device interface module is disclosed for use with the Unix (Unix is a trademark of AT&T) operating system which is flexible enough to support many types of disk or tape device drivers. A common disk module (CDM) is included. The CDM contains high level disk operation commands which may be used for common reference to each disk driver on the system. Routines within the CDM are accessed by the Unix system call interface through a series of operating system entry points. Additional routines are included with the pre-existing Unix operating system Disk I/O Subsystem to improve interfacing between this subsystem and the CDM. A common tape module (CTM) is used to perform high level tape operation routines. The Unix system call interface communicates with the CTM through a group of operating system entry points. Because there is no Unix operating system tape I/O subsystem, the CTM completely implements a tape I/O subsystem. To provide hardware portability, the CTM is configured to call a group of low level routines which have been incorporated into a device driver. Because of the large number of possible root disk device drives, the root disk device driver can be dynamically selected for the Unix operating system. Each controller which is resident within the system checks in with the operating system. The controller which checks in first with the operating system is used for booting up the system. Each controller which checks in is matched with an appropriate device driver. The matched device drivers are then used for disk I/O functions.

Claims25

Dependent claims

In a computer system including storage means and including a memory in which a plurality of program images are stored, swapped out and transferred to said storage means, apparatus for dynamically selecting a boot disk device driver for a Unix operating system from among a plurality of disk device drivers, comprising:

a. first indication means for determining if each of said plurality of disk device drivers is coupled to a respective one of a plurality of disk drive controllers;
b. second indication means for determining presence of at least one of a plurality of disk drives wherein each of said plurality of disk drives are coupled to a respective one of said plurality of disk device drivers;
c. transfer means, responsive to at least one of said first and second indication means, for transferring to the Unix operating system a value which uniquely identifies one of said plurality of disk drive controllers as said boot disk drive controller if a disk drive of said plurality of disk drives which is coupled to said one of said plurality of disk drive controllers has a root disk number;
d. means for a) coupling said boot disk drive controller to a corresponding device driver b) configuring said corresponding device driver as said boot disk device driver for booting said computer system;
and c) indicating to said computer system that said corresponding device driver is used for transferring to said storage means ones of said plurality of images swapped out of said memory.

2 more elements

Apparatus for transferring a first input/output (I/O) request between a Unix operating system and a first peripheral device controller coupled to a first I/O device and for transferring a second I/O request between said Unix operating system and a second peripheral device controller coupled to a second I/O device, each Of said first I/O request and said second I/O request one of a read request and a write request, said apparatus comprising:

a. Unix system call interface means for receiving said first I/O request and said second I/O request;
b. common device module means including a) common write means for writing data to either one of said first peripheral device controller and said second peripheral device controller and b) common read means for reading data from either one of said first peripheral device controller and said second peripheral device controller.
c. first and second operating system interface means, coupled to said Unix system call interface means, for receiving the first I/O request and the second I/O request, respectively, and for mapping each of the first I/O request and the second I/O request to one of said common read means and said common write means;
and
d. first and second device driver means, coupled to said first peripheral device controller and said second peripheral device controller respectively, for transferring said first I/O request between either one of said common write means and said common read means and said first peripheral device controller and for transferring said second I/O request between either one of said common write means and said common read means and said second peripheral device controller.

2 more elements

Dependencies are inferred from the claim text.

Peripheral device interface for dynamically selecting boot disk device driver

Life of this patent

Peripheral device interface for dynamically selecting boot disk device driver

Life of this patent

Abstract

Claims25