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Date: Wed, 11 Oct 2023 21:22:06 -0700
From: Christoph Hellwig <hch@infradead.org>
To: charlesfdotz@tutanota.com
Cc: Damien Le Moal <dlemoal@kernel.org>, Hannes Reinecke <hare@suse.de>,
	Dm Devel <dm-devel@lists.linux.dev>
Subject: Re: Feature Request: Device Manager Fake Trim / Zero Trim
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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.