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Subject: Re: [PATCH 3/4] autofs - make mountpoint checks namespace aware
From: Ian Kent <raven@themaw.net>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Mateusz Guzik <mguzik@redhat.com>, NeilBrown <neilb@suse.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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Date: Sat, 24 Sep 2016 08:11:09 +0800
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On Fri, 2016-09-23 at 14:15 -0500, Eric W. Biederman wrote:
> Ian Kent <raven@themaw.net> writes:
> 
> 2> On Thu, 2016-09-22 at 20:37 -0500, Eric W. Biederman wrote:
> > > Ian Kent <raven@themaw.net> writes:
> > > 
> > > > On Thu, 2016-09-22 at 10:43 -0500, Eric W. Biederman wrote:
> > > > > Ian Kent <raven@themaw.net> writes:
> > > > > 
> > > > > > Eric, Mateusz, I appreciate your spending time on this and
> > > > > > particularly
> > > > > > pointing
> > > > > > out my embarrassingly stupid is_local_mountpoint() usage mistake.
> > > > > > 
> > > > > > Please accept my apology for the inconvenience.
> > > > > > 
> > > > > > If all goes well (in testing) I'll have follow up patches to correct
> > > > > > this
> > > > > > fairly
> > > > > > soon.
> > > > > 
> > > > > Related question.  Do you happen to know how many mounts per mount
> > > > > namespace tend to be used?  It looks like it is going to be wise to
> > > > > put
> > > > > a configurable limit on that number.  And I would like the default to
> > > > > be
> > > > > something high enough most people don't care.  I believe autofs is
> > > > > likely where people tend to use the most mounts.
> > 
> > Yes, I agree, I did want to try and avoid changing the parameters to
> > ->d_mamange() but passing a struct path pointer might be better in the long
> > run
> > anyway.
> 
> Given that there is exactly one implementation of d_manage in the tree I
> don't imagine it will be disruptive to change that.

Yes, but it could be used by external modules.

And there's also have_submounts().

I can update that using the existing d_walk() infrastructure or take it (mostly)
into the autofs module and get rid of have_submounts().

I'll go with the former to start with and see what people think.

> 
> Eric