From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nick Piggin Subject: Re: [RFC][PATCH] Add a dentry op to handle automounting rather than abusing follow_link Date: Thu, 22 Jul 2010 14:15:54 +1000 Message-ID: <20100722041554.GB3446@amd> References: <27282.1279058150@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: viro@ZenIV.linux.org.uk, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: David Howells Return-path: Received: from ipmail04.adl6.internode.on.net ([150.101.137.141]:12080 "EHLO ipmail04.adl6.internode.on.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750734Ab0GVEQB (ORCPT ); Thu, 22 Jul 2010 00:16:01 -0400 Content-Disposition: inline In-Reply-To: <27282.1279058150@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: This hasn't had much comments yet. On Tue, Jul 13, 2010 at 10:55:50PM +0100, David Howells wrote: > > Add a dentry op (d_automount) to handle automounting directories rather than > abusing the follow_link() inode operation. > > I've only changed __follow_mount() to handle automount points, but it might be > necessary to change follow_mount() too. The latter is only used from > follow_dotdot(), but any automounts on ".." should be pinned whilst we're using > a child of it. > > AFS is made to use this facility so that it can be tested. Other filesystems > abusing the follow_mount() inode operation will also need to be modified. How about having a .follow_mount op, and using that instead of default follow_mount in case mounted is incremented? Also I would prefer the patch to add this call keep basically the same API as follow_mount, so if you are going to change that to return an error and do the NOFOLLOW handling in there, then could you do that first, as a more trivial patch? Then your addition of the d_op should not touch outside *follow_mount.