From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout01.posteo.de (mout01.posteo.de [185.67.36.65]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 14F5D19ABD8 for ; Fri, 12 Sep 2025 15:32:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.67.36.65 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757691154; cv=none; b=LgI91JPf2S/rUU3G7mPSSRmZZmXOz7Aa+x8eWRxKrlNBkTX6v589f781oPB+8UFYWLcpzSQSYRoWRgcWN+IDrYyBofm7/LVYrue5HrpUJaSaDCRnBFRw/0yDC4VBLOFi+pZAIfRA25GCbRs2xYczMTb5Vz4cRAosXt4r1Nsj5G4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757691154; c=relaxed/simple; bh=SLQ7ShI3cjyhcYd8hqed5EOccgJbaNdA/DCM7QMU6nQ=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=izpA4tLm7A1NS0m8B28I1CiOp/9iap//sX3bsXcrqf+hr0YbITuFepME4ZP3znkXYbi9bfbYk67MqPmGeAGlTHEYXsBM+a0Br9Rw4X0/O/V6eNqfu7f4DGd8WA45zD4OaGh5N+wrv4xXkxbkyopiRcvsDDQN49t57wMmfnU1L0o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.net; spf=pass smtp.mailfrom=posteo.net; dkim=pass (2048-bit key) header.d=posteo.net header.i=@posteo.net header.b=fVACUB16; arc=none smtp.client-ip=185.67.36.65 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=posteo.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=posteo.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=posteo.net header.i=@posteo.net header.b="fVACUB16" Received: from submission (posteo.de [185.67.36.169]) by mout01.posteo.de (Postfix) with ESMTPS id 45D6C240029 for ; Fri, 12 Sep 2025 17:32:30 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=posteo.net; s=2017; t=1757691150; bh=IA5YNAoVNsEwinWOmnpmB4qrPZxT2JToTJ4rBj7Ifb8=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type:From; b=fVACUB1637j70F0nGEjP26fGFuqcHyj9SgDGbpOrbW3FlCDkLmSNFZRxRpXSMqZlj upPQMz8ALJQ8d+8h7EavcStwNk4kR8QUwyS6HkUicD/gKVswdj35KMugjk9lfQiZj5 G7w1OSbgTfAbbMx4ikuPJBbXMudXo7bTtExjgJWSyQmQ9O4rDr63TA8I4EireDdsPg ie+h9m8nRVb/Vka9TRjdECeahLh8/89klKe3QhUW9YfTm4xb+lVIhNjFcMrfOiE4Hf UeH08jxunTPGfWiL1opqLUK+CB4qm66szqLzu+hurBdD8F2cKRWHa4qcad81c2wsIr OfFi/5DsrnGpw== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 4cNdhs2N0Mz6tx2 for ; Fri, 12 Sep 2025 17:32:29 +0200 (CEST) From: Nicholas Hubbard To: linux-unionfs@vger.kernel.org Subject: Support for including nested mountpoints in overlay? Date: Fri, 12 Sep 2025 15:32:29 +0000 Message-ID: <87plbvadpw.fsf@slackpad.slackpad.domain> Precedence: bulk X-Mailing-List: linux-unionfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" --=-=-= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Hello everybody, I have just started working with overlayfs, and ran into a problem. Specifi= cally I wanted to overlay the root of my filesystem with a command like the follo= wing: # mount -t overlay overlay -o lowerdir=3D/,upperdir=3D./tmp-upper,workdir= =3D./tmp-work ./merged However, I noticed that my nested btrfs subvolumes and boot partition were = not included in ./merged. I quickly learned though that you could have multiple lowerdirs. So next I tried the following command (I have a nested btrfs sub= volume at /home, and my boot partition mounted at /boot): # mount -t overlay overlay -o lowerdir=3D/:/home:/boot,upperdir=3D./tmp-upp= er,workdir=3D./tmp-work ./merged I was expecting that now I would have (for example) the following directori= es: ./merged/home/$USER ./merged/boot/grub However I instead had: ./merged/$USER ./merged/grub Which shows that all the lowerdirs are placed right at the root of the merg= edir. So I have two questions. 1. Is there a (easy) way say "I want to include all nested mountpoints into= the overlay in their same directories"? 2. If there is not a (easy) way to do this, do you think it would be both f= easible and useful to add such a feature? If the answer to question 2 is "yes", then I would be happy to take a try a= t this :) =2D-=20 Nicholas B. Hubbard Keys: https://github.com/NicholasBHubbard/public-keys Key ID: 508022AE06C2C446D8072447C700A066BB25F148 --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEARYKAB0WIQRQgCKuBsLERtgHJEfHAKBmuyXxSAUCaMQ9CwAKCRDHAKBmuyXx SDVdAP4tK/Zrnh7EHJWTlgbiN1X6Gs94zb56sC2ypt7vrmCmGQD/SF50rj/a6OYA jNeeAsYzDWtWLzm1zh09Zm8GgR0t3wg= =Xhuq -----END PGP SIGNATURE----- --=-=-=--