Re: [PATCH v5 RESEND 10/17] s390: mm: Convert to GENERIC_IOREMAP

From: Christoph Hellwig
Date: Wed May 17 2023 - 02:36:32 EST


On Mon, May 15, 2023 at 05:08:41PM +0800, Baoquan He wrote:
> +#define ioremap_wc(addr, size) \
> + ioremap_prot((addr), (size), pgprot_val(pgprot_writecombine(PAGE_KERNEL)))

I'd move this out of line and just apply mio_wb_bit_mask directly
instead of the unbox/box/unbox/box dance.

> +#define ioremap_wt(addr, size) \
> + ioremap_prot((addr), (size), pgprot_val(pgprot_writethrough(PAGE_KERNEL)))

and just define this to ioremap_wc. Note that defining _wt to _wc is
very odd and seems wrong, but comes from the existing code. Maybe the
s390 maintainers can chime on on the background and we can add a comment
while we're at it.

Otherwise looks good:

Reviewed-by: Christoph Hellwig <hch@xxxxxx>