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Date: Tue, 27 Aug 2024 07:47:57 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>,
	Chandan Babu R <chandan.babu@oracle.com>,
	Christian Brauner <brauner@kernel.org>, linux-xfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH 02/10] iomap: improve shared block detection in
 iomap_unshare_iter
Message-ID: <20240827054757.GA11067@lst.de>
References: <20240827051028.1751933-1-hch@lst.de> <20240827051028.1751933-3-hch@lst.de> <20240827054424.GM6043@frogsfrogsfrogs>
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On Mon, Aug 26, 2024 at 10:44:24PM -0700, Darrick J. Wong wrote:
> Maybe we should rename it then?
> 
> IOMAP_F_OUT_OF_PLACE_WRITE.
> 
> Yuck.
> 
> IOMAP_F_ELSEWHERE
> 
> Not much better.  Maybe just add a comment that "IOMAP_F_SHARED" really
> just means an out of place write (aka srcmap is not just a hole).

Heh.

For writes it usually means out of place write, but for reporting
it gets translated to the FIEMAP_EXTENT_SHARED flag or is used to
reject swapon.  And the there is black magic in DAX.