Abstract: A storage device comprising a storage medium having a plurality of sectors and a superset format. Each sector includes a header, a data section and a trailer, the data section sized to contain a number of bytes per sector equal to or greater than a maximum of subset formats to be supported. Meta data in a non-user portion of the storage medium includes a flag for indicating a subset format such that each sector is formatted to store less than the number of bytes.

Abstract: At least one input/output (I/O) firmware partition is provided in a partitioned environment to facilitate access to I/O resources owned by the at least one I/O firmware partition. The I/O resources of an I/O firmware partition are shared by one or more other partitions of the environment, referred to as consumer partitions. The consumer partitions use the I/O firmware partition to access the I/O resources. Since the I/O firmware partitions are responsible for providing access to the I/O resources owned by those partitions, the consumer partitions are relieved of this task, reducing complexity and costs in the consumer partitions.

Abstract: An I/O adapter sharing mechanism in a logically partitioned computer system allows sharing a network I/O adapter between logical partitions in an efficient manner. A first logical partition owns (or controls) the I/O adapter, and a second logical partition desires to use (or share) the I/O adapter. An I/O adapter device driver that includes a hardware interface is provided in the first logical partition. A virtual device driver is provided in the second logical partition that provides a set of functions that is at least partially defined by querying the I/O adapter device driver in the first logical partition. The I/O adapter sharing mechanism includes a transfer mechanism that allows data to be transferred directly from the virtual device driver in the second logical partition to the I/O adapter without passing through the I/O adapter device driver in the first logical partition.