System and method for implementing virtual adapters and virtual interfaces in a network system

In a shared I/O subsystem that couples a plurality of computer systems to at least one shared I/O interface, the shared I/O subsystem having at least one physical adapter associated with the at least one shared I/O interface, a plurality of virtual I/O interfaces, and a forwarding function, the forwarding function having a forwarding table that includes a plurality of entries corresponding to each of the virtual I/O interfaces, a method comprising:

• communicatively coupling the virtual I/O interfaces to the computer systems, wherein each of the computer systems includes a virtual adapter that communicates with one of the virtual I/O interfaces;
• receiving, with the forwarding function, a first I/O packet from one of the virtual I/O interfaces;
• directing, by using the forwarding table, the first I/O packet to at least one of the physical adapter and one or more of other ones of the virtual I/O interfaces;
• receiving, with the forwarding function, a second I/O packet from the physical adapter;
• and
• directing, by using the forwarding table, the second I/O packet to one or more of the virtual I/O interfaces.

A shared I/O subsystem that couples a plurality of computer systems to at least one shared I/O interface, the shared I/O subsystem having at least one physical adapter associated with the at least one shared I/O interface, a plurality of virtual I/O interfaces, and a forwarding function, the forwarding function having a forwarding table that includes a plurality of entries corresponding to each of the virtual I/O interfaces, comprising:

• means for communicatively coupling the virtual I/O interfaces to the computer systems, wherein each of the computer systems includes a virtual adapter that communicates with one of the virtual I/O interfaces;
• means for receiving, with the forwarding function, a first I/O packet from one of the virtual I/O interfaces;
• means for directing, by using the forwarding table, the first I/O packet to at least one of the physical adapter and one or more of other ones of the virtual I/O interfaces;
• means for receiving, with the forwarding function, a second I/O packet from the physical adapter;
• and
• means for directing, by using the forwarding table, the second I/O packet to one or more of the virtual I/O interfaces.