Re: [PATCH] riscv: introduce the ioremap_prot() function

[Christoph Hellwig]

> +{
> +	phys_addr_t addr = PFN_PHYS(pfn);
> +
> +	/* avoid false positives for bogus PFNs, see comment in pfn_valid() */
> +	if (PHYS_PFN(addr) != pfn)
> +		return 0;
> +
> +	return memblock_is_map_memory(addr);
> +}
> +EXPORT_SYMBOL(pfn_is_map_memory);

This should not be exported or even exposed.  Please just open code it
in the only caller.

> +void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,
> +			   pgprot_t pgprot)
> +{
> +	/* Don't allow RAM to be mapped. */
> +	if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr))))
> +		return NULL;

Or just use pfn_valid as that's what we usually use for that check.
Or am I missing something specific here?

It would also be nice to just life this to common code.