schemas. Disk information and disk geometry are designed to replace
information currently conveyed to user space using struct disklabel.
- Add a dk_info member to struct disk; a reference to a disk information
dictionary. This dictionary is to be allocated and the reference stored
in struct disk by individual drivers.
- disk_detach0() will release dk_info if non-NULL.
- Convert the wd(4) driver to stash geometry and other disk properties
as the "disk-info" property in its properties dictionary. This needs
some cleanup, but will serve as an example of what to do with other
disk drivers.