I'm trying to make my own device mapper, which first maps the bio (read) request onto another one. However, after completion of the remapped request, I want to access the data that was read. I've been looking at the important data structures, and see no field members that would contain the read data (eg. struct bio, bio_vec, bvec_iter, etc.)
I feel lost cause it would seem like such a straightforward thing to do, and yet I can't find it.