Re: [PATCH v3 5/5] lib, pci: unify generic pci_iounmap()

From: Arnd Bergmann
Date: Mon Dec 04 2023 - 09:31:27 EST


On Mon, Dec 4, 2023, at 15:09, Philipp Stanner wrote:
> On Mon, 2023-12-04 at 14:50 +0100, Arnd Bergmann wrote:
>> On Mon, Dec 4, 2023, at 14:39, Philipp Stanner wrote:
>> > On Mon, 2023-12-04 at 13:38 +0100, Philipp Stanner wrote:
>
> Ok, makes sense.
>
> But should we then adjust iomem_is_ioport() in asm-generic/io.h, as
> well, so that it matches IO_COND()'s behavior?
>
> It currently does this:
>
> uintptr_t start = (uintptr_t)PCI_IOBASE;
> uintptr_t addr = (uintptr_t)addr_raw;
>
> if (addr >= start && addr < start + IO_SPACE_LIMIT)
> return true;
>
> and if the architecture does not set PCI_IOBASE, then it's set per
> default to 0, as well.
>
> So we have two inconsistent definitons

No, I would also keep the logic here, since it makes more sense
and the inconsistency is only for the corner case that doesn't
hit in practice.

The PCI_IOBASE==0 case should never happen here, as that doesn't
work with the generic inb(). I think the only target left that
has I/O ports but doesn't set PCI_IOBASE at all is sparc, but
that is special in a number of ways.

Arnd