Re: [PATCH v3 04/10] block: introduce dma map backed bio type

[Christoph Hellwig]

> +	union {
> +		struct bio_vec		*bi_io_vec;
> +		/* Driver specific dma map, present only with BIO_DMABUF_MAP */
> +		struct io_dmabuf_map	*dmabuf_map;
> +	};

... and please add the bi_ prefix we're using for all (well except for
one oddity) fields in struct bio.