This directory contains the classes that ecapsulate creation of DMA buffers and the handling of their scatter-gather lists.
The PdaDmaBufferProvider and FilePdaDmaBufferProvider are used for real DMA buffers from memory regions or
memory-mapped files, registered with PDA.
The NullDmaBufferProvider may be used to instantiate a DmaChannel without a real buffer, e.g. for testing
purposes.