Re: [PATCH v5 6/8] device-dax: use struct_size()

[Christoph Hellwig]

> +             pgmap = devm_kzalloc(
> +                       dev, struct_size(pgmap, ranges, dev_dax->nr_range - 
> 1),
> +                       GFP_KERNEL);

Keeping the dev argument on the previous line would not only make this
much more readable but also avoid the overly long line.