I/O bus abstraction for a cluster interconnection fabric

A host to be coupled to a cluster interconnection fabric including one or more fabric-attached I/O controllers, the host comprising:

• a processor;
• memory coupled to the processor;
• and
• an operating system including:
• a kernel;
• and
• a fabric bus driver to provide an I/O bus abstraction to the kernel for the cluster interconnection fabric.

A host to be coupled to a cluster interconnection fabric including one or more fabric-attached I/O controllers, the host comprising:

• a processor;
• memory coupled to the processor;
• and
• an operating system including:
• a kernel;
• and
• a fabric bus driver that presents the cluster interconnection fabric to the kernel as a local I/O bus.

An operating system for a host, the host being coupled to a cluster interconnection fabric including one or more fabric attached I/O controllers, the operating system comprising:

• a kernel;
• an I/O manager operatively coupled to the kernel;
• one or more I/O controller drivers operatively coupled to the kernel, each controller driver specific for a specific type of I/O controller;
• and
• a fabric bus driver operatively coupled to the I/O manager to provide an I/O bus abstraction to the I/O manager for the cluster interconnection fabric.

A method of coupling a host to a fabric-attached I/O controller, the method comprising the steps of:

• coupling a host to a cluster interconnection fabric including a fabric-attached I/O controller, the host including an operating system, wherein the host operating system presumes that any I/O controllers directly accessible by the host are connected to a local I/O bus;
• and
• providing a fabric bus driver for allowing the host to directly access the fabric-attached I/O controller, the fabric bus driver providing a local I/O bus abstraction to:
• a) present the cluster interconnection fabric to the host operating system as a local I/O bus;
• and
• b) to identify the fabric-attached I/O controller to the host operating system as being a local I/O controller attached to a local I/O bus of the host.

A network comprising:

• a cluster interconnection fabric;
• a host connected to the cluster interconnection fabric, the host including an operating system;
• an I/O controller attached to the cluster interconnection fabric;
• the host operating system including a fabric bus driver, the fabric bus driver providing a local I/O bus abstraction to:
• a) present the cluster interconnection fabric to the host operating system as a local I/O bus;
• and
• b) identify the fabric-attached I/O controller to the host operating system as being a local I/O controller attached to a local I/O bus.

A computer program encoded on a computer readable medium, the computer program causing the following to be performed when executed by a host computer:

• providing a local I/O bus abstraction to:
• a) present a cluster interconnection fabric to a host operating system of the host computer as a local I/O bus;
• and
• b) identify a fabric-attached I/O controller to the host operating system as being a local I/O controller attached to a local I/O bus.

A method of initializing a host comprising the steps of:

• loading an operating system kernel into memory;
• loading an I/O manager into memory;
• loading a local I/O bus driver and a fabric bus driver into memory, the fabric bus driver providing a local I/O bus abstraction for a cluster interconnection fabric that is connected to the host;
• the local I/O bus driver identifying any local I/O controllers connected to a corresponding local I/O bus;
• the fabric bus driver identifying any fabric-attached I/O controllers assigned to the host;
• and
• reporting the identified local I/O controllers connected to the local bus and the identified fabric-attached I/O controllers to the I/O manager.

A method of initializing a host comprising the steps of:

• loading an operating system kernel into memory;
• loading an I/O manager into memory;
• loading a fabric bus driver into memory;
• the fabric bus driver identifying any fabric-attached I/O controllers assigned to the host;
• and
• the fabric bus driver reporting the identified fabric-attached I/O controllers to the I/O manager.