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Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <111000.1736867714@warthog.procyon.org.uk> To: Miklos Szeredi Cc: dhowells@redhat.com, mszeredi@redhat.com, linux-unionfs@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: How to support directory opacity in a filesystem for overlayfs to use? Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <112183.1736870193.1@warthog.procyon.org.uk> Content-Transfer-Encoding: quoted-printable Date: Tue, 14 Jan 2025 15:56:33 +0000 Message-ID: <112184.1736870193@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 Miklos Szeredi wrote: > On Tue, 14 Jan 2025 at 16:15, David Howells wrote: > = > > What's the best way for a network filesystem to make a native > > directory-is-opaque flag available to the system? Is it best to catch > > setxattr/getxattr/removexattr("overlay.opaque") and translate these in= to the > > RPCs to wrangle the flag? > = > I don't know. Out of curiosity, which filesystem is it? One of the varieties of AFS. Unfortunately, xattrs aren't a thing and can= 't easily be added because of the volume transfer and backup protocols and formats. > There's "trusted.overlay.opaque" and "user.overlay.opaque" and are > used in different scenarios. There was also talk of making the > "trusted." namespace nest inside user namespaces, but apparently it's > not so important. > = > Which one would you like to emulate? Um - I don't know the difference to answer that question. David