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	Fri, 30 Jan 2026 05:14:27 +0000
Date: Fri, 30 Jan 2026 05:14:26 +0000
From: Matthew Wilcox <willy@infradead.org>
To: Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc: JP Kobryn <inwardvessel@gmail.com>, boris@bur.io, clm@fb.com,
	dsterba@suse.com, linux-btrfs@vger.kernel.org,
	linux-kernel@vger.kernel.org, kernel-team@meta.com,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>
Subject: Re: [RFC PATCH] btrfs: defer freeing of subpage private state to
 free_folio
Message-ID: <aXw-MiQWyYtZ3brh@casper.infradead.org>
References: <20260129230822.168034-1-inwardvessel@gmail.com>
 <776e54f6-c9b7-4b22-bde5-561dc65c9be7@gmx.com>
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In-Reply-To: <776e54f6-c9b7-4b22-bde5-561dc65c9be7@gmx.com>

On Fri, Jan 30, 2026 at 01:46:59PM +1030, Qu Wenruo wrote:
> Another question is, why only two fses (nfs for dir inode, and orangefs) are
> utilizing the free_folio() callback.

Alas, secretmem and guest_memfd are also using it.  Nevertheless, I'm
not a fan of this interface existing, and would prefer to not introduce
new users.  Like launder_folio, which btrfs has also mistakenly used.