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Date: Tue, 29 Nov 2011 12:27:02 -0500
From: "J. Bruce Fields" <bfields@fieldses.org>
To: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Peng Tao <bergwolf@gmail.com>, tao.peng@emc.com, skinsbursky@parallels.com,
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Subject: Re: [PATCH 4/5] NFS: remove RPC PipeFS mount point reference from
 blocklayout routines
Message-ID: <20111129172702.GB19528@fieldses.org>
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On Tue, Nov 29, 2011 at 12:19:25PM -0500, Trond Myklebust wrote:
> 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.

OK, that makes sense.

--b.