[PATCH v4 12/18] mm/hmm: provide generic DMA managing logic

[Christoph Hellwig]

> +dma_addr_t hmm_dma_map_pfn(struct device *dev, struct hmm_dma_map *map,
> +			   size_t idx, struct pci_p2pdma_map_state *p2pdma_state);

Please avoid the overly long line.