SG_FLAG_LAST
sgd->flags = SG_FLAG_LAST;
request.sg_descriptors[0].flags = SG_FLAG_LAST;
request.sg_descriptors[0].flags = SG_FLAG_LAST;
sg_array[num_sg - 1].flags = SG_FLAG_LAST;
sg_chain[num_sg - 1].flags = SG_FLAG_LAST;