From: Roman Mamedov <rm@romanrm.net>
To: Ulli Horlacher <framstag@rus.uni-stuttgart.de>
Cc: Linux fs Btrfs <linux-btrfs@vger.kernel.org>
Subject: Re: finding root filesystem of a subvolume?
Date: Tue, 22 Aug 2017 21:48:18 +0500 [thread overview]
Message-ID: <20170822214818.72bb4638@natsu> (raw)
In-Reply-To: <20170822154537.GJ14804@rus.uni-stuttgart.de>
On Tue, 22 Aug 2017 17:45:37 +0200
Ulli Horlacher <framstag@rus.uni-stuttgart.de> wrote:
> In perl I have now:
>
> $root = $volume;
> while (`btrfs subvolume show "$root" 2>/dev/null` !~ /toplevel subvolume/) {
> $root = dirname($root);
> last if $root eq '/';
> }
>
>
If you are okay with rolling your own solutions like this, take a look at
"btrfs filesystem usage <path>". It will print the blockdevice used for
mounting the base FS. From that you can find the mountpoint via /proc/mounts.
Performance-wise it seems to work instantly on an almost full 2TB FS.
--
With respect,
Roman
next prev parent reply other threads:[~2017-08-22 16:48 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-08-22 12:23 finding root filesystem of a subvolume? Ulli Horlacher
2017-08-22 12:40 ` Hugo Mills
2017-08-22 12:50 ` Ulli Horlacher
2017-08-22 12:58 ` Marat Khalili
2017-08-22 13:12 ` Ulli Horlacher
2017-08-22 13:41 ` Marat Khalili
2017-08-22 13:27 ` Austin S. Hemmelgarn
2017-08-22 13:30 ` Ulli Horlacher
2017-08-22 13:37 ` Austin S. Hemmelgarn
2017-08-22 13:45 ` Marat Khalili
2017-08-22 13:53 ` Ulli Horlacher
2017-08-22 14:12 ` Austin S. Hemmelgarn
2017-08-22 14:23 ` Hugo Mills
2017-08-22 14:37 ` Austin S. Hemmelgarn
2017-08-22 14:43 ` Peter Grandi
2017-08-22 15:03 ` Austin S. Hemmelgarn
2017-08-22 15:45 ` Ulli Horlacher
2017-08-22 16:48 ` Roman Mamedov [this message]
2017-08-22 17:41 ` Peter Grandi
2017-08-23 12:07 ` Austin S. Hemmelgarn
2017-08-23 13:14 ` Axel Burri
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