blockif_read
int blockif_read(struct blockif_ctxt *bc, struct blockif_req *breq);
err = blockif_read(p->bctx, breq);
err = blockif_read(p->bctx, breq);
err = blockif_read(nvstore->ctx, &req->io_req);
err = blockif_read(sc->bc, &io->io_req);