Patent ID: 8185683

Claim:
A bridge for routing a PCI-enabled input-output bus of a processor unit to a PCI-enabled input-output bus of a switching device via which a plurality of processor units are connected to each other, comprising: an upstream port adapted to a global address space into which effective addresses of the processor units are mapped and which is shared by the plurality of processor units, the upstream port being operative to receive from the associated processor unit an access request packet designating an effective address of a target node represented by one of the plurality of processor units; a controller provided with a converter operative to convert the effective address of the target node into a global address by appending to the effective address of the target node a node identification number identifying the target node and necessary for switching; and a downstream port operative to output the access request packet designating the global address to the switching device, wherein the controller is further provided with a confirmation unit operative to confirm, after an access request packet for a posted write operation is output and before the target node is notified that the posted write operation is completed, whether the posted write operation is completed in the target node, wherein a confirmation is made when the confirmation unit creates and outputs through the downstream port an access request packet for a non-posted read operation designating the global address specified by the access request packet for the posted write operation, and after the confirmation unit checks if the non-posted read operation is successfully completed, and wherein the controller is provided with an order guaranteeing unit operative to permit the output of a notification packet issued by the associated processor unit and configured to notify a target node that a posted write operation is completed, on the condition that confirmation is established that the execution of an access request packet prior to the notification packet and requesting the posted write operation in the target node is completed, and wherein the notification packet is a packet for initiating a process of reading data written by the access request packet for a posted write operation in the target node.