Message-ID: <sashiko-outbox-208100@kernel.org>
From: sashiko-bot@kernel.org
Subject: Re: [PATCH 2/4] fuse: don't move pipe buffers into the page cache
Reply-To: sashiko-reviews@lists.linux.dev
To: =?utf-8?b?S2lyeWwgU2h1dHNlbWF1IChNZXRhKQ==?= <kas@kernel.org>
Cc: virtualization@lists.linux.dev, "Michael S. Tsirkin" <mst@redhat.com>, "Eugenio
 Perez" <eperezma@redhat.com>
In-Reply-To: <20261110145241.536019-3-kas@kernel.org>
References: <20261110145241.536019-1-kas@kernel.org>
 <20261110145241.536019-3-kas@kernel.org>
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Date: Wed, 11 Nov 2026 02:35:41 +0000
Precedence: list

> A splice() into /dev/fuse with SPLICE_F_MOVE lets the reply to a read
> request steal full pages from the pipe.  Each stolen page replaces, in
> the fuse file's page cache, the folio that the request allocated.  The
> page can be a page cache folio of another file, a page written into the
> pipe, or a gifted user page.
>=20
> Always copy.  The server sees the same data, and the move was a hint
> that splice() never promised to honour.
>=20
> Keep advertising FUSE_SPLICE_MOVE.  libfuse fails the mount of a
> filesystem that asks for a capability the kernel does not offer.
>=20
> Preparation for removing ->try_steal() from pipe buffers.
>=20
> Suggested-by: David Hildenbrand (Arm) <david@kernel.org>
> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
> Signed-off-by: Kiryl Shutsemau (Meta) <kas@kernel.org>

Sashiko has reviewed this patch and found no issues.

--=20
Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20261110145241.5360=
19-1-kas@kernel.org?part=3D2