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Date: Fri, 23 Jan 2026 08:24:33 +0100
From: Christoph Hellwig <hch@lst.de>
To: "Darrick J. Wong" <djwong@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>, Eric Biggers <ebiggers@kernel.org>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	David Sterba <dsterba@suse.com>, Theodore Ts'o <tytso@mit.edu>,
	Jaegeuk Kim <jaegeuk@kernel.org>, Chao Yu <chao@kernel.org>,
	Andrey Albershteyn <aalbersh@redhat.com>,
	"Matthew Wilcox (Oracle)" <willy@infradead.org>,
	linux-fsdevel@vger.kernel.org, linux-btrfs@vger.kernel.org,
	linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net,
	fsverity@lists.linux.dev
Subject: Re: [PATCH 07/11] fs: consolidate fsverity_info lookup in buffer.c
Message-ID: <20260123072433.GA27421@lst.de>
References: <20260122082214.452153-1-hch@lst.de> <20260122082214.452153-8-hch@lst.de> <20260122214958.GG5910@frogsfrogsfrogs> <20260123051556.GC24123@lst.de> <20260123072329.GL5910@frogsfrogsfrogs>
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On Thu, Jan 22, 2026 at 11:23:29PM -0800, Darrick J. Wong wrote:
> On Fri, Jan 23, 2026 at 06:15:56AM +0100, Christoph Hellwig wrote:
> > On Thu, Jan 22, 2026 at 01:49:58PM -0800, Darrick J. Wong wrote:
> > > Well this is no longer a weird ext4ism, since f2fs also needs this,
> > > right?  Maybe this comment should read:
> > 
> > f2fs doesn't use buffer heads.  So this is just because ext4 only
> > implements the easy parts of ->read_folio and ->readahead itself and
> > falls back onto the generic code for the rest, which then had to be
> > grow hacky ext4-specific bits like this for it :(
> 
> Yikes.  So I guess we shouldn't genericise the comment to encourage more
> people to do the same thing ext4 did?

I don't think so.  I actually need to send a ping to the ext4 folks
that maybe, maybe they really should handle all reads into the page
cache in their own code so that we can hopefully kill this entirely.