Hi Charles,
you are doing a whole lot of handwaiving here (and not even following
the Linux mailing list style).
If you actually have a driver with your alleged behavior you can
simply switch the scsi disk driver to zero blocks on discard by
doing an
echo "writesame_zero" > /sys/.../provisioning_mode
and get your behavior. I very much doubt you'll find such a drive.
There are exactly three hard drive manufactures left, with just a few
models each, and they are pretty well understood. You've even got
feedback from the prime expert on hard drive handling in Linux who
works for one of them.
