Abstract: A system and method which provide a mechanism for an I/O virtualization management partition (IMP) to control the shared functionality of an I/O virtualization (IOV) enabled I/O adapter (IOA) through a physical function (PF) of the IOA while the virtual functions (VFs) are assigned to client partitions for normal I/O operations directly. A hypervisor provides device-independent facilities to the code running in the IMP and client partitions. The IMP may include device specific code without the hypervisor needing to sacrifice its size, robustness, and upgradeability. The hypervisor provides the virtual intermediary functionally for the sharing and control of the IOA's control functions.

Abstract: The system and method address the situation where an input/output (I/O) fabric is shared by more than one logical partition (LPAR) and where each LPAR can share with the other LPARs an I/O adapter (IOA). In particular, each LPAR is assigned its own separate address space to access a virtual function (VF) assigned to it such that each LPAR's perception is that it has its own independent IOA. Each VF may be shared across multiple LPARs. Facilities are provided for management of the shared resources of the IOA via a Physical Function (PF) of the IOA by assignment of that PF to an I/O Virtualization Management Partition (IMP). The code running in the IMP acts as a virtual intermediary to the VFs for fully managing the VF error handling, VF reset, and configuration operations. The IMP also acts as an interface to the PF for accessing common VF functionality.

Abstract: A method, mechanism and computer usable medium is provided for distributing I/O fabric errors to the appropriate root nodes in a multi-root environment. The case where the I/O fabric is attached to more than one root node and where each root can potentially share with the other roots the I/O adapter (IOA) resources which are attached to the I/O is addressed. Additionally, a method, mechanism and computer usable medium is provided by which errors detected in an I/O fabric may be routed to all root nodes which may be affected by the error, while not being reported to the root nodes that will not be affected by those errors. In particular, distributed computing system which uses the PCI Express protocol to communicate over the I/O fabric is addressed.

Abstract: A system and method for registering combinations of physical and/or virtual functions for configuring an endpoint are provided. With the system and method, a mechanism informs a management component of a multifunction endpoint's functional combinations. The management component may then use this information to select the functional combinations that are to be made visible to each system image. The informing of the management component may be performed by writing values to various predefined fields in a configuration space for a physical or virtual function that provides information regarding the number of virtual functions supported, the combination of functions supported, a nominal combination of virtual functions to be used by the physical function, and a group identifier for identifying which functions are linked in a combination grouping.

Abstract: A computer-implemented method, apparatus, and computer usable program code are disclosed for migrating a virtual adapter from a source physical adapter to a destination physical adapter in a data processing system where multiple host computer systems share multiple adapters and communicate with those adapters through a PCI switched-fabric bus. The virtual adapter is first caused to stop processing transactions. All in-flight transactions that are associated with the virtual adapter are then captured. The configuration information that defines the virtual adapter is moved from the source physical adapter to the destination physical adapter. The in-flight transactions are then restored to their original locations on the destination virtual adapter. The virtual adapter is then restarted on the destination physical adapter such that the virtual adapter begins processing transactions.

Abstract: A method is directed to use of a master root node, in a distributed computer system provided with multiple root nodes, to control the configuration of routings through an I/O switched-fabric. One of the root nodes is designated as the master root node or PCI Configuration Manager (PCM), and is operable to carry out the configuration while each of the other root nodes remains in a quiescent or inactive state. In one useful embodiment pertaining to a system of the above type, that includes multiple root nodes, PCI switches, and PCI adapters available for sharing by different root nodes, a method is provided wherein the master root node is operated to configure routings through the PCI switches. Respective routings are configured between respective root nodes and the PCI adapters, wherein each of the configured routings corresponds to only one of the root nodes.

Abstract: A method, mechanism and computer usable medium is provided for distributing I/O fabric errors to the appropriate root nodes in a multi-root environment. The case where the I/O fabric is attached to more than one root node and where each root can potentially share with the other roots the I/O adapter (IOA) resources which are attached to the I/O is addressed. Additionally, a method, mechanism and computer usable medium is provided by which errors detected in an I/O fabric may be routed to all root nodes which may be affected by the error, while not being reported to the root nodes that will not be affected by those errors. In particular, distributed computing system which uses the PCI Express protocol to communicate over the I/O fabric is addressed.

Abstract: A mechanism, method and computer usable medium is provided for each root node of a multiple root node system and its own independent address space. This mechanism also allows multiple system images within the same root node to have their own independent address spaces. A mechanism is also provided for incorporating legacy root node and input/output adapters that are non-aware of the mechanisms introduced by this invention. Input/ output adapters which implement this invention may also have the number of functions that they support greatly expanded beyond the present eight functions per input/output adapter.

Abstract: A computer-implemented method, apparatus, and computer usable program code are disclosed for migrating a virtual adapter from a source physical adapter to a destination physical adapter in a data processing system where multiple host computer systems share multiple adapters and communicate with those adapters through a PCI switched-fabric bus. The virtual adapter is first caused to stop processing transactions. All in-flight transactions that are associated with the virtual adapter are then captured. The configuration information that defines the virtual adapter is moved from the source physical adapter to the destination physical adapter. The in-flight transactions are then restored to their original locations on the destination virtual adapter. The virtual adapter is then restarted on the destination physical adapter such that the virtual adapter begins processing transactions.

Abstract: A method and apparatus is provided for routing error messages in a distributed computer system comprising multiple root nodes, and further comprising one or more PCI switches and one or more I/O adapters, wherein each root node includes one or more system images. In one useful embodiment, a method is provided for routing I/O error messages to root nodes respectively associated with the errors contained in the messages. The method includes detecting occurrence of an error at a specified one of the adapters, wherein the error affects one of the system images, and generating an error message at the specified adapter. The method further comprises routing the error message from the specified adapter to the particular root node that includes the affected system image. The error message is then selectively processed at the particular root node, in order to identify the affected system image.

Abstract: Method and system for address routing in a distributed computing system, such as a distributed computing system that uses PCI Express protocol to communicate over an I/O fabric. A destination identifier is provided to identify a physical or virtual host or end point. When a physical or virtual host or end point receives a PCI data packet it compares a list of source identifiers with destination identifiers to determine if a source identifier included in the transaction packet is associated with a destination identifier included in the transaction packet to determine if the transaction packet has a valid association. If the transaction packet has a valid association, it is routed to the target device. The present invention enables each host that attaches to PCI bridges or switches and shares a set of common PCI devices to have its own PCI 64-bit address space and enables the routing of PCI transaction packets between multiple hosts and adapters, through a PCI switched-fabric bus using a destination identifier.

Abstract: A method and apparatus is provided for routing error messages in a distributed computer system comprising multiple root nodes, and further comprising one or more PCI switches and one or more I/O adapters, wherein each root node includes one or more system images. In one useful embodiment, a method is provided for routing I/O error messages to root nodes respectively associated with the errors contained in the messages. The method includes detecting occurrence of an error at a specified one of the adapters, wherein the error affects one of the system images, and generating an error message at the specified adapter. The method further comprises routing the error message from the specified adapter to the particular root node that includes the affected system image. The error message is then selectively processed at the particular root node, in order to identify the affected system image.

Abstract: Method and system for address routing in a distributed computing system, such as a distributed computing system that uses PCI Express protocol to communicate over an I/O fabric. A destination identifier is provided to identify a physical or virtual host or end point. When a physical or virtual host or end point receives a PCI data packet it compares a list of source identifiers with destination identifiers to determine if a source identifier included in the transaction packet is associated with a destination identifier included in the transaction packet to determine if the transaction packet has a valid association. If the transaction packet has a valid association, it is routed to the target device. The present invention enables each host that attaches to PCI bridges or switches and shares a set of common PCI devices to have its own PCI 64-bit address space and enables the routing of PCI transaction packets between multiple hosts and adapters, through a PCI switched-fabric bus using a destination identifier.

Abstract: A method is directed to use of a master root node, in a distributed computer system provided with multiple root nodes, to control the configuration of routings through an I/O switched-fabric. One of the root nodes is designated as the master root node or PCI Configuration Manager (PCM), and is operable to carry out the configuration while each of the other root nodes remains in a quiescent or inactive state. In one useful embodiment pertaining to a system of the above type, that includes multiple root nodes, PCI switches, and PCI adapters available for sharing by different root nodes, a method is provided wherein the master root node is operated to configure routings through the PCI switches. Respective routings are configured between respective root nodes and the PCI adapters, wherein each of the configured routings corresponds to only one of the root nodes.

Abstract: A computer-implemented method, apparatus, and computer program product are disclosed in a data processing environment that includes host computer systems that are coupled to adapters utilizing a switched fabric for routing packets between the host computer systems and the adapters. A unique destination identifier is assigned to one of the host computer systems. A portion of a standard format packet destination address is selected. Within a particular packet, the portion is set equal to the unique identifier that is assigned to the host computer system. The particular packet is then routed through the fabric to the host computer system using the unique destination identifier.

Abstract: A method is directed to use of a master root node, in a distributed computer system provided with multiple root nodes, to control the configuration of routings through an I/O switched-fabric. One of the root nodes is designated as the master root node or PCI Configuration Manager (PCM), and is operable to carry out the configuration while each of the other root nodes remains in a quiescent or inactive state. In one useful embodiment pertaining to a system of the above type, that includes multiple root nodes, PCI switches, and PCI adapters available for sharing by different root nodes, a method is provided wherein the master root node is operated to configure routings through the PCI switches. Respective routings are configured between respective root nodes and the PCI adapters, wherein each of the configured routings corresponds to only one of the root nodes.

Abstract: A system and method for migration of stateless virtual functions from one virtual plane to another are provided. When a migration of a source virtual function to a destination virtual function in another virtual plane is to be performed, a source single root PCI manager (SR-PCIM) is first interrupted by a multiple root PCI manager (MR-PCIM). Configuration information that defines the source virtual function is then redefined on the destination virtual function for this stateless migration. A function level reset may then be performed on the source virtual function. The destination SR-PCIM may be interrupted by the MR-PCIM with an interrupt for the destination virtual function. A function level reset may then be performed on the destination virtual function. The destination virtual function state may then be changed to an “active” state such that the migrated virtual function begins processing transactions.

Abstract: A system and method for communication between host systems using a transaction protocol and shared memories are provided. Shared memories are initialized based on a discovery process in a communication fabric such that at least one endpoint has address ranges in shared memories of at least two host systems. A transaction oriented protocol may be established for using the shared memories of the host systems to communicate between root complexes and endpoints of the same or different host systems. The transaction oriented protocol specifies a series of transactions to be performed by the various elements, e.g., root complex or endpoint, to push or pull data. Various combinations of push and pull transactions may be utilized.

Abstract: A system and method for registering combinations of physical and/or virtual functions for configuring an endpoint are provided. With the system and method, a mechanism informs a management component of a multifunction endpoint's functional combinations. The management component may then use this information to select the functional combinations that are to be made visible to each system image. The informing of the management component may be performed by writing values to various predefined fields in a configuration space for a physical or virtual function that provides information regarding the number of virtual functions supported, the combination of functions supported, a nominal combination of virtual functions to be used by the physical function, and a group identifier for identifying which functions are linked in a combination grouping.

Abstract: A system and method for migration of single root stateless virtual functions are provided. A Single-Root PCI Configuration Manager (SR-PCIM) provides a system image (SI) with possible virtual function (VF) migration scenarios supported by the endpoint (EP). The SR-PCIM may be instructed that a stateless migration of a VF and its associated application(s) from one SI to another is required. Outstanding requests to the VF are completed and any applications associated with the VF are removed from the SI and the VF is detached from its associated physical function (PF). The SWI may then attach the VF to a target PF which may be in the same or a different EP. The SWI makes the VF available to the SI with which the VF is now associated and the SI configures the VF thereby making it available for use by associated applications.