Message-ID: <1322587165.4174.20.camel@lade.trondhjem.org>
Subject: Re: [PATCH 4/5] NFS: remove RPC PipeFS mount point reference from
 blocklayout routines
From: Trond Myklebust <Trond.Myklebust@netapp.com>
To: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Peng Tao <bergwolf@gmail.com>, tao.peng@emc.com, skinsbursky@parallels.com,
        linux-nfs@vger.kernel.org, xemul@parallels.com, neilb@suse.de,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        jbottomley@parallels.com, davem@davemloft.net, devel@openvz.org
Date: Tue, 29 Nov 2011 12:19:25 -0500
In-Reply-To: <20111129164252.GA19528@fieldses.org>
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On Tue, 2011-11-29 at 11:42 -0500, J. Bruce Fields wrote: 
> On Tue, Nov 29, 2011 at 11:40:30AM -0500, Trond Myklebust wrote:
> > I mean that I'm perfectly entitled to do
> > 
> > 'modprobe -r blocklayoutdriver'
> > 
> > and when I do that, then I expect blkmapd to close the rpc pipe and wait
> > for a new one to be created just like rpc.idmapd and rpc.gssd do when I
> > remove the nfs and sunrpc modules.
> 
> The rpc pipefs mount doesn't hold a reference on the sunrpc module?

I stand corrected: the mount does hold a reference to the sunrpc
module. 
However nothing holds a reference to the blocklayoutdriver module, so
the main point that the "blocklayout" pipe can disappear from underneath
the blkmapd stands.

-- 
Trond Myklebust
Linux NFS client maintainer

NetApp
Trond.Myklebust@netapp.com
www.netapp.com