> > However I worry that this just leaves driver authors too much rope.
> > Choosing readq_atomic() vs. readq() is just one more thing to get wrong.
> ... as is having each driver implementing their own substitutes.
Yes, I agree with that. However at least status quo ante (readq/writeq
64-bit only) means that driver authors who use readq/writeq are forced
(by a compile error) to spend a little thought on what 32-bit fallback
they should use.
I guess one possibility is to make readq/writeq the atomic version, and
add readq_nonatomic()/writeq_nonatomic() for 32-bit architectures. Then
it's much more opt-in -- but then that makes the (perhaps) more common
case look a bit uglier.