device and driver in-memory structure layouts - label and number

While I appreciate that the use of C struct syntax is illustrative only, the in-memory structures it documents are normative.

And in a number of cases, those in-memory structures occur in the same numbered section, making reference to any specified in-memory structure uncertain.

Labeling and numbering the in-memory structures (to say nothing of adding anchors for remote pointing), would greatly improve the usefulness of this document.