From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from resqmta-ch2-05v.sys.comcast.net ([69.252.207.37]:50764 "EHLO resqmta-ch2-05v.sys.comcast.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753305AbaKRKw3 (ORCPT ); Tue, 18 Nov 2014 05:52:29 -0500 Message-ID: <546B24E9.2020705@pobox.com> Date: Tue, 18 Nov 2014 02:52:25 -0800 From: Robert White MIME-Version: 1.0 To: Btrfs BTRFS Subject: BUG :: btrfs resize should require mount point not just /some/path Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-btrfs-owner@vger.kernel.org List-ID: So here's a thing... If you've got a BTRFS root file system and you mount go to resize a removable media and you make a typo you can easily resize your root instead of a target. mkdir /media/vol1 /media/vol2 mount /dev/sdz1 /media/vol2 # intended vol1 btrfs resize -32G /media/vol1 umount /dev/sdz1 #proceed to fark up /dev/sdz1 with partitioning tools Since resize will accept _any_ existing directory (or even filename?) as the target of a resize instead of limiting the targets to known mount-points it pretty much invites mistakes. The system _should_ error out on any path thats not a mount point in the name of safety alone. A message like "/some/path not a mounted file system" would be less surprising than operating on a file system when any arbitrary directory is named.