Re: [PATCH 6/6] arch/*/: remove CONFIG_VIRT_TO_BUS

Geert Uytterhoeven
2022-06-07T07:29:55Z

On Mon, Jun 6, 2022 at 11:10 AM Arnd Bergmann <arnd@kernel.org> wrote:
> From: Arnd Bergmann <arnd@arndb.de>
>
> All architecture-independent users of virt_to_bus() and bus_to_virt()
> have been fixed to use the dma mapping interfaces or have been
> removed now. This means the definitions on most architectures, and the
> CONFIG_VIRT_TO_BUS symbol are now obsolete and can be removed.
>
> The only exceptions to this are a few network and scsi drivers for m68k
> Amiga and VME machines and ppc32 Macintosh. These drivers work correctly
> with the old interfaces and are probably not worth changing.
>
> On alpha and parisc, virt_to_bus() were still used in asm/floppy.h.
> alpha can use isa_virt_to_bus() like x86 does, and parisc can just
> open-code the virt_to_phys() here, as this is architecture specific
> code.
>
> I tried updating the bus-virt-phys-mapping.rst documentation, which
> started as an email from Linus to explain some details of the Linux-2.0
> driver interfaces. The bits about virt_to_bus() were declared obsolete
> backin 2000, and the rest is not all that relevant any more, so in the
> end I just decided to remove the file completely.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

> arch/m68k/Kconfig | 1 -
> arch/m68k/include/asm/virtconvert.h | 4 +-

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds