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Date: Mon, 14 Oct 2024 08:21:25 +0200
From: Christoph Hellwig <hch@lst.de>
To: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>,
	Javier =?iso-8859-1?Q?Gonz=E1lez?= <javier.gonz@samsung.com>,
	Keith Busch <kbusch@kernel.org>,
	"Martin K. Petersen" <martin.petersen@oracle.com>,
	Kanchan Joshi <joshi.k@samsung.com>, hare@suse.de, sagi@grimberg.me,
	brauner@kernel.org, viro@zeniv.linux.org.uk, jack@suse.cz,
	jaegeuk@kernel.org, bcrl@kvack.org, dhowells@redhat.com,
	bvanassche@acm.org, asml.silence@gmail.com,
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	io-uring@vger.kernel.org, linux-block@vger.kernel.org,
	linux-aio@kvack.org, gost.dev@samsung.com, vishak.g@samsung.com
Subject: Re: [PATCH v7 0/3] FDP and per-io hints
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On Fri, Oct 11, 2024 at 11:08:26AM -0600, Jens Axboe wrote:
> 
> I think that last argument is a straw man - for any kind of interface
> like this, we've ALWAYS just had the rule that any per-whatever
> overrides the generic setting.

And exactly that is the problem.  For file systems we can't support
that sanely.  So IFF you absolutely want the per-I/O hints we need
an opt in by the file operations.  I've said that at least twice
in this discussion before, but as everyone likes to have political
discussions instead of technical ones no one replied to that.