Abstract: A method, system, and apparatus for isolating an input/output (I/O) bus error, received from an I/O adapter, from the other I/O adapters that may be in different partitions within a logically partitioned data process system is provided. In one embodiment, the logically partitioned data processing system includes a system bus, a processing unit, a memory unit, a host bridge, a plurality of terminal bridges, and a plurality of input/output adapters. The processing unit, memory unit, and the host bridge are all coupled to each other through the system bus. Each of the plurality of terminal bridges is coupled to the host bridge through a first bus. Each of the input/output adapters is coupled to one of the plurality of terminal bridges through a one of a plurality of second buses, such that each input/output adapter corresponds to a single terminal bridge. Each of the input/output adapters are assigned to one of a plurality of logical partitions within the data processing system.

Abstract: A method, system, and apparatus for preventing input/output (I/O) adapters used by an operating system (OS) image, in a logically partitioned system, from accessing data from a memory location allocated to another OS image is provided. The system includes logical partitions, operating systems (OSs), memory locations, I/O adapters (IOAs), and a hypervisor. Each operating system image is assigned memory locations and input/output adapter is assigned to a logical partition. Each of the input/output adapters is assigned a range of I/O bus DMA addresses by the hypervisor. When a DMA operation request is received from an OS image, the hypervisor checks that the memory address range and the I/O adapter are allocated to the requesting OS image and that the I/O bus DMA range is within the that allocated to the I/O adapter. If these checks are passed, the hypervisor performs the requested mapping; otherwise the request is rejected.

Abstract: A method, system, and apparatus for making all content addressable memory words available for comparison in a data compressor is provided. In one embodiment, new data, to be compared with old data, is launched into a master. The new data from the master latch is launched into a slave latch and compare logic for each of a plurality of content addressable memory words within a content addressable memory (CAM). After the comparison has been made between the new data and the old data contained within the CAM word, the new data from the slave latch is written into the one of the plurality of content addressable memory words. Thus, each CAM word, including the CAM word that will be overwritten by the new data, is available for comparison to the new data.