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Date: Mon, 29 Apr 2024 07:10:28 +0200
From: Christoph Hellwig <hch@lst.de>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org,
	Christian Brauner <brauner@kernel.org>,
	Christoph Hellwig <hch@lst.de>, linux-block@vger.kernel.org,
	Jens Axboe <axboe@kernel.dk>, linux-btrfs@vger.kernel.org,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [PATCH 4/7] swapon(2): open swap with O_EXCL
Message-ID: <20240429051028.GE32416@lst.de>
References: <20240427210920.GR2118490@ZenIV> <20240427211128.GD1495312@ZenIV> <CAHk-=wiag-Dn=7v0tX2UazhMTBzG7P42FkgLSsVc=rfN8_NC2A@mail.gmail.com> <20240427234623.GS2118490@ZenIV> <20240428181934.GV2118490@ZenIV> <CAHk-=wgPpeg1fj4zk0mvCmpYrrs0jVqrFrRONNFgA8Yq6nLTeg@mail.gmail.com> <20240428190709.GX2118490@ZenIV>
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On Sun, Apr 28, 2024 at 08:07:09PM +0100, Al Viro wrote:
> Christoph, do you have any plans along those lines for swap devices?
> If they are not going to grow holder_ops, I'd say we should switch
> to O_EXCL open and be done with that; zram is in the same situation,
> AFAICS.

holder_ops right now are used for fs freezing, fs syncing and dead
device notification.  None of this is useful for swap, as is the
resize notification I plan to add eventually.