[PATCHv4] blk: Replace SG_GAPGS with new queue limits mask

[Sagi Grimberg]

> -static int req_gap_to_prev(struct request *req, struct request *next)
> +static int req_gap_to_prev(struct request *req, struct bio *next)
>   {
>   	struct bio *prev = req->biotail;
>
> -	return bvec_gap_to_prev(&prev->bi_io_vec[prev->bi_vcnt - 1],
> -				next->bio->bi_io_vec[0].bv_offset);
> +	return bvec_gap_to_prev(req->q, &prev->bi_io_vec[prev->bi_vcnt - 1],
> +			next->bi_io_vec[1].bv_offset);

Keith,

is the index change in the bi_io_vec intentional?