+
+	bio_set_dev(bio, bdev);
+	bio->bi_iter.bi_sector = sector;
+	bio_set_op_attrs(bio, op, op_flags);

This function is obsolete. Open code this.

And that also mean that you could remove one argument to bio_new(): combine op
and op_flags into "unsigned int opf"

I did that initially but kept it separate for RFC, that is much easier than having

an extra arg, will change it in V1.