US 5,414,851 A · Method and means for sharing I/O resources by a plurality of operating systems

Abstract

Provides a method for increasing the connectivity of I/O resources to a multiplicity of operating systems (OSs) running in different resource partitions of a computer electronic complex (CEC) to obtain sharing of the I/O resources among the OSs of the CEC, including channels, subchannels (devices), and control units (CUs). The invention provides image identifiers (IIDs) for assigning resources to the different OSs. Each shared I/O resource has a sharing set of control blocks (CBs) in which a respective CB is assigned to (and located by) a respective IID of one of the OSs. Each of the CBs in a sharing set provides a different image of the same I/O resource. The different CB images are independently set to different states by I/O operations for the different OSs, so that the OSs can independently share the same I/O resource.

Claims30

Dependent claims

A method for sharing input/output (I/O) resources among a plurality of programs in a computer electronic complex, each of said plurality of programs assigned an image identifier, said method including the steps of:

storing in said computer electronic complex a sharing set of input/output control blocks, each input/output control block of said sharing set of input/output blocks including an input/output resource identifier and an image identifier;
accessing said sharing set of input/output control blocks in said computer electronic complex in response to an input/output request of one of said plurality of programs;
accessing a control block in said sharing set of input/output control blocks, accessed in the just previous step, with an image identifier of said one of said plurality of programs;
and
storing states of input/output resources in said control block accessed in the just previous accessing step, whereby said control block presents separate images of the input/output resources to each of said plurality of programs.

2 more elements

A method of sharing I/O resources by a plurality of operating systems (OSs), comprising the steps of:

storing an image identifier (IID) in a resource identifying control block (SD) for each of plural OSs operating in a computer electronic complex (CEC);
structuring within an I/O-control storage for the CEC of a set of I/O control blocks (CBs) for each of plural I/O resources of the CEC, and associating each CB in the set with a different IID;
and
accessing a required CB by an I/O processor for an I/O operation by selecting a set of CBs with an identifier of an I/O resource and by selecting a required CB in a selected set with the IID stored in the SD of an OS requesting the I/O operation, and sharing the I/O resource among the OSs associated with the IIDs of the different CBs in the set.

1 more element

A method of efficiently sharing I/O channels, I/O control units, and I/O devices by a plurality of operating systems (OSs), comprising the steps of:

storing in processor storage one or more special control blocks (SDs) containing OS identifiers (IIDs) for use in I/O resource sharing operations of a computer electronic complex (CEC);
storing in I/O storage a sharing set of subchannel control blocks (SSCBs) for each subchannel (for a shared I/O device), each SSCB in the set having a different IID;
storing in the I/O storage of a sharing set of channel control blocks (CHCBs) for the same I/O channel (shared channel) in which each CHCB in the set has a different IID;
storing in the I/O storage a sharing set of logical control unit control blocks (LCUCBs) for each logical I/O control unit in which each LCUCB in the set has a different IID;
and
controlling an I/O operation for a requesting OS by obtaining an IID for the OS and selecting an SSCB with the IID in a sharing set for a required subchannel I/O resource, and selecting a LCUCB with the IID in a sharing set for a required control unit I/O resource, and selecting a CHCB with the IID in a sharing set for a required channel I/O resource, thereby enabling the OS to share the required I/O channel and the required I/O control unit and the required I/O device with at least one other OS operating in the CEC.

3 more elements

Dependencies are inferred from the claim text.

Method and means for sharing I/O resources by a plurality of operating systems

Life of this patent

Method and means for sharing I/O resources by a plurality of operating systems

Life of this patent

Abstract

Claims30