What effect does negating an unsigned number have? It's not something I've
ever tried... I suppose strictly, the answer probably ought to be zero.
My ~phys_addr+1 does the 2's complement, just as negate does.
> if (!size || -phys_addr < size)
> return NULL;
This looks fairly reasonable, apart from the fact the condition should be "<="
not "<", otherwise my particular case is excluded.
David Howells