Abstract: Input/output (I/O) operation requests from pageable storage mode guests are interpreted without host intervention. In a pageable mode virtual environment, requests issued by pageable storage mode guests are processed by one or more processors of the environment absent intervention from one or more hosts of the environment. Processing of the requests includes manipulating, by at least one processor on behalf of the guests, buffer state information stored in host storage. The manipulating is performed via instructions initiated by the guests and processed by one or more of the processors.

Abstract: Protection of cryptographic keys is converted between one level of security and another level of security. The one level of security is different from the another level of security, and the another level of security includes the components of the one level of security.

Abstract: A system, method and computer program product for translations in a computer system. The system includes a general purpose register containing a base address of an address translation table. The system also includes a millicode accessible special displacement register configured to receive a plurality of elements to be translated. The system further includes a multiplexer for selecting a particular one of the plurality of elements from the millicode accessible special displacement register and for generating a displacement or offset value. The system further includes an address generator for creating a combined address containing the base address from the general purpose register and the generated displacement or offset value.

Abstract: An apparatus is disclosed for operating a symmetric cipher engine (SCE) in cipher-block chaining (CBC) mode, the apparatus comprises a crypto operation hardware comprising said SCE, an XOR stage, an apparatus for storing a chaining value comprising a state register of said SCE, an input latch supplying said crypto operation hardware with data, and an output latch. The data may be reordered for decipher operations. Furthermore, a method is disclosed for operating a SCE in CBC mode, wherein the method involves a crypto operation hardware that comprises said SCE and an XOR stage supplied with data. The method may also comprise using a state register of said SCE to apply a chaining value. Said method may comprise reordering data supplied to said crypto operation hardware for decipher operations.

Abstract: Input/output (I/O) operation requests from pageable storage mode guests are interpreted without host intervention. In a pageable mode virtual environment, requests issued by pageable storage mode guests are processed by one or more processors of the environment absent intervention from one or more hosts of the environment. Processing of the requests includes manipulating, by at least one processor on behalf of the guests, buffer state information stored in host storage. The manipulating is performed via instructions initiated by the guests and processed by one or more of the processors.

Abstract: A method of operating a computer system is described. The computer system comprises a processor and a co-processor wherein the co-processor is coupled to an output buffer for loading a number of output data units into the output buffer and wherein the processor is coupled to the output buffer for fetching the loaded output data units. The co-processor generates a trigger condition such that the last output data unit is being fetched by the processor from the output buffer as shortly as possible after it has been loaded to the output buffer by the co-processor.