From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759501Ab0FPXOt (ORCPT ); Wed, 16 Jun 2010 19:14:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:18321 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758615Ab0FPXOs (ORCPT ); Wed, 16 Jun 2010 19:14:48 -0400 Date: Wed, 16 Jun 2010 19:14:22 -0400 From: Valerie Aurora To: Ian Kent Cc: Alexander Viro , autofs@linux.kernel.org, Miklos Szeredi , linux-kernel@vger.kernel.org, Christoph Hellwig , linux-fsdevel@vger.kernel.org, Jan Blunck Subject: Re: [autofs] [PATCH 04/38] autofs4: Save autofs trigger's vfsmount in super block info Message-ID: <20100616231421.GD13908@shell> References: <1276627208-17242-1-git-send-email-vaurora@redhat.com> <1276627208-17242-5-git-send-email-vaurora@redhat.com> <1276661043.2339.35.camel@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1276661043.2339.35.camel@localhost> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 16, 2010 at 12:04:03PM +0800, Ian Kent wrote: > On Tue, 2010-06-15 at 11:39 -0700, Valerie Aurora wrote: > > From: Jan Blunck > > > > XXX - This is broken and included just to make union mounts work. See > > discussion at: > > > > http://kerneltrap.org/mailarchive/linux-fsdevel/2010/1/15/6708053/thread > > Instead of saving the vfsmount we could save a pointer to the dentry of > the mount point in the autofs super block info struct. I think that's > the bit I don't have so it would be sufficient for a lookup_mnt() for > the needed vfsmount in ->follow_mount(). > > Objections? > Suggestions? I'm not sure... it seems like it would have the same problem that Al described with pinning the vfsmount forever. But I don't know autofs at all. Could you run through a quick example of the case that triggers this problem in the first place? The problem is when you have a symlink that triggers an automount, and you are trying to get from the target of the symlink to the vfsmount of the file system containing the symlink in the first place? Or do I have that wrong? Thanks, -VAL