Abstract: Computer program products and methods for efficient handling of queued-direct input/output (QDIO) requests and completions at an adapter in communication with an I/O device are provided. A method includes accessing a queue with one or more storage block address lists (SBALs), where each SBAL includes a plurality of storage block address list entries (SBALEs) and is associated with an SLSB. The method further includes reading an SBAL count in one of the SBALEs, where the SBAL count indicates a number of the SBALs forming an I/O request to the I/O device. In response to determining that the SBAL count is greater than one, a number of the SBALs from the queue and associated SLSBs equivalent to the SBAL count are prefetched without waiting for a notification of completion of each of the SBALs forming the I/O request, and states of the associated SLSBs transition from adapter-owned to program-owned.

Abstract: Computer program products and methods for efficient handling of queued-direct input/output (QDIO) requests and completions at an adapter in communication with an I/O device are provided. A method includes accessing a queue with one or more storage block address lists (SBALs), where each SBAL includes a plurality of storage block address list entries (SBALEs) and is associated with an SLSB. The method further includes reading an SBAL count in one of the SBALEs, where the SBAL count indicates a number of the SBALs forming an I/O request to the I/O device. In response to determining that the SBAL count is greater than one, a number of the SBALs from the queue and associated SLSBs equivalent to the SBAL count are prefetched without waiting for a notification of completion of each of the SBALs forming the I/O request, and states of the associated SLSBs transition from adapter-owned to program-owned.

Abstract: A method and apparatus for detecting errors within an incorrect media access control address and for preventing an Ethernet device from using the incorrect media access control address while it is fully operating. The method and apparatus can also correct some types of errors within the media access control address so that the Ethernet device may operate using a correct media access control address.