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Date: Fri, 12 Sep 2025 09:19:35 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Andrey Albershteyn <aalbersh@redhat.com>,
	Christoph Hellwig <hch@lst.de>, fsverity@lists.linux.dev,
	linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org,
	david@fromorbit.com, ebiggers@kernel.org,
	Andrey Albershteyn <aalbersh@kernel.org>
Subject: Re: [PATCH RFC 02/29] iomap: introduce iomap_read/write_region
 interface
Message-ID: <20250912071935.GC13505@lst.de>
References: <20250728-fsverity-v1-0-9e5443af0e34@kernel.org> <20250728-fsverity-v1-2-9e5443af0e34@kernel.org> <20250729222252.GJ2672049@frogsfrogsfrogs> <20250811114337.GA8850@lst.de> <pz7g2o6lo6ef5onkgrn7zsdyo2o3ir5lpvo6d6p2ao5egq33tw@dg7vjdsyu5mh> <20250912011433.GH1587915@frogsfrogsfrogs>
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On Thu, Sep 11, 2025 at 06:14:33PM -0700, Darrick J. Wong wrote:
> TBH I've started wondering if what fsverity wants is filemap_fault(),
> but with a special flag that enables faults beyond EOF.  After all, it
> creates a folio, reads the data from disk, and returns a locked folio.

filemap_faul actually does a lot of mmap-specific things.