Patent ID: 8037217

Claim:
A method of direct memory access (‘DMA’) in a computing environment, the computing environment comprising a plurality of computers and one or more DMA engines, the computers adapted to one another for data communications by an data communications fabric, each computer executing an application capable of issuing DMA requests to a DMA engine, the method comprising: pinning, by a first application executing on a first computer, a memory region for DMA transfer of data, including providing, to all applications executing in the computing environment, information describing the memory region; effecting, by a second application executing on a second computer in dependence upon the information describing the memory region, DMA transfers related to the memory region, including issuing DMA requests to a particular DMA engine for processing; and unpinning, by the first application after effecting a plurality of DMA transfers related to the memory region, the memory region, including insuring, prior to unpinning, that no additional DMA requests related to the memory region are issued, that all outstanding DMA requests related to the memory region are provided to a DMA engine, and that processing of all outstanding DMA requests related to the memory region and provided to a DMA engine has been completed.