The DISK I/O subsystem is contained in a single eCos package,
CYGPKG_IO_DISK. However, it depends on the services of the following
other packages for complete functionality:
CYGPKG_IO
Device IO package. Disk devices operate within the generic
device infrastructure.
CYGPKG_ERROR
The error package. Disk devices need to return standard error
codes when operations fail.
The DISK I/O package can be added to any configuration just by adding
its package during configuration. However, it is usually added as part
of a group which also includes a filesystem implementation and
hardware device drivers.