Re: PATCH 2.3.23.5: physical address typedef

Albert D. Cahalan (acahalan@cs.uml.edu)
Fri, 22 Oct 1999 22:10:26 -0400 (EDT)


Jamie Lokier writes:
> Jes Sorensen wrote:

>> Type typedef's are a pain when there is no real reason for them,
>> ie. for atomic types and spin locks there is a good reason, for simple
>> pointers there aren't.
>
> A bus address is not a pointer...
>
>> Addind yet another random typedef just makes the code even more
>> obfuscated. You will be able to do just as much damage with this new
>> type as you can do with unsigned long's.
>
> Obfuscation? If it's made mandatory right away I agree. If it's the
> wrong name, I agree. (kphysaddr_t is the wrong name). If it has the
> wrong semantics: i.e., it doesn't always hold a bus address, I agree.
> But if it does have a consistent meaning how can you call it
> obfuscation?
>
> Bear in mind that unsigned long is the *wrong* type (on x86 with 64-bit
> PCI), though that hasn't arrived yet. And char * is also the wrong
> type.

It looks like the AS/400 port will need 128-bit pointers.
(and a trap handler to set/clear the hidden 129th bit IMHO...)

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