seebs@plethora.net (Peter Seebach) writes:

> In message <mtuu0as4x1z.fsf@contents-vnder-pressvre.mit.edu>, "Nathan J. Willia
> ms" writes:
> >Note the "extent_flags" hack in powerpc/powerpc/bus_space.c. It
> >doesn't bother to allocate the extent for bootstrap uses... but
> >there's no corresponding check in the unmap code. My interpretation of
> >this is that bootstrap code should feel free to not bother to unmap
> >the region; adding the matching extent_flags hack to the unmap code
> >would be okay, too.
> 
> Hmm.  My main concern about not unmapping is just that, according to the
> bus_space man page, it's perfectly reasonable to refuse to map something
> that's already mapped.  So, if I've mapped the registers for this device,
> a later bus_space_map for these registers could legitimately fail.

Feel free to read the implementation and take its word over the man
page :)

        - Nathan