From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from frost.carfax.org.uk ([85.119.82.111]:33356 "EHLO frost.carfax.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932615AbdHVMkh (ORCPT ); Tue, 22 Aug 2017 08:40:37 -0400 Received: from hrm by frost.carfax.org.uk with local (Exim 4.80) (envelope-from ) id 1dk8U0-0007WC-SS for linux-btrfs@vger.kernel.org; Tue, 22 Aug 2017 12:40:36 +0000 Date: Tue, 22 Aug 2017 12:40:36 +0000 From: Hugo Mills To: linux-btrfs@vger.kernel.org Subject: Re: finding root filesystem of a subvolume? Message-ID: <20170822124036.GA32302@carfax.org.uk> References: <20170822122350.GA14804@rus.uni-stuttgart.de> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="G4iJoqBmSsgzjUCe" In-Reply-To: <20170822122350.GA14804@rus.uni-stuttgart.de> Sender: linux-btrfs-owner@vger.kernel.org List-ID: --G4iJoqBmSsgzjUCe Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Aug 22, 2017 at 02:23:50PM +0200, Ulli Horlacher wrote: > How do I find the root filesystem of a subvolume? > Example: > > root@fex:~# df -T > Filesystem Type 1K-blocks Used Available Use% Mounted on > - - 1073740800 104244552 967773976 10% /local/.backup/home I've never seen the "- -" output from df before. Is this a bind mount or something? > root@fex:~# btrfs subvolume show /local/.backup/home > /local/.backup/home > Name: home > uuid: f86a2db0-6a82-124f-9a71-1cd4c20fd6fb > Parent uuid: ba4d388f-44bf-7b46-b2b8-00e2a9a87181 > Creation time: 2017-08-10 22:19:15 > Object ID: 383 > Generation (Gen): 148 > Gen at creation: 148 > Parent: 5 > Top Level: 5 > Flags: readonly > Snapshot(s): > > > I know, the root filesystem is /local, but who can I show it by command? Probably in /proc/self/mountinfo -- that should give you the full set of applied mount options, plus the original source for the mount (which will be a block device for most filesystem mounts, a path for bind mounts, or something FS-specific for network filesystems). Hugo. -- Hugo Mills | And what rough beast, its hour come round at last / hugo@... carfax.org.uk | slouches towards Bethlehem, to be born? http://carfax.org.uk/ | PGP: E2AB1DE4 | W.B. Yeats, The Second Coming --G4iJoqBmSsgzjUCe Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iQIcBAEBAgAGBQJZnCZEAAoJEFheFHXiqx3kfwQP/AjO9Ey9WItpMx7v0AX45U0a 6Ozc+qONUYz5sDJ6A0wrtkRTiotDscjPdjbAw/P69c6zVPq3ML7d/zKTitjeSPfQ K7ekOMan8l9xbtSYSibiCAJQZ8x+Njg7HHsDJ2gUE2H8BnU8zIK2A4kbW4FBAeVl INTWRBDFtGN/4L4AxFO4SkYgOIcwkjWZTwmpEmBN/U+ovJzGO+pvhla79jEPgMgN JujJg52+P/9kFXkC1mcLyuxVXK/pUFOAoYDkaKr82mdXP6i8Bdp74wJIH1GURdaN ZBueEYmqCrrhcehlRJKZzsuOns5LOZ2H0HA9MD/QTMFuqc82rRjyz1X+cN5c26UF X6U9MQWQo7QyCk22sSffETzDarhWl4YKKrBeJ8OUS6Fv5FJJjuPHg4M8T9ZG5/oa B88fQ8Br7rMnKFoCUbmhW9lYzXWClzJtCSn/PqzYHbDs53MssNEbBSIaCFjAyHrP iw/7Tpw594EvjMU/nqWf8Tvyg9IUfL5hwLCfKn9QBPBiF04vNnjUcnBgIlnVtBdR B0saAcQk1Y+uIl32Bg4MsrUHS8h9SICo6TPkK/bm9BbeLzc93GKW7P4/WFsTQWGq k++cDZmZdug5XQ1FugoYMxbTVV2MGGvHRJI03avjjvRqfx7DhV37lWZTVJZ32Jpt P0MxqxJSEC9Yo/RhPh9/ =oaoB -----END PGP SIGNATURE----- --G4iJoqBmSsgzjUCe--