For simplicity this trait implements a default version that has a
topology with 512 byte (i.e. sector) recommended sizes.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>
Both DiskFile and AsyncIo traits are introduced to allow all kind of
files (RAW, QCOW, VHD) to be able to handle asynchronous access to the
underlying file.
Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>