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Subject: Re: mount / unmount and mountcheckdirs()
To: Konstantin Belousov <kostikbel@gmail.com>,
 Edward Napierala <trasz@FreeBSD.org>
Cc: Kirk McKusick <mckusick@mckusick.com>, freebsd-fs <freebsd-fs@FreeBSD.org>,
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From: Andriy Gapon <avg@FreeBSD.org>
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Date: Fri, 15 Sep 2017 19:40:22 +0300
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On 15/09/2017 19:27, Konstantin Belousov wrote:
> On Fri, Sep 15, 2017 at 05:06:10PM +0100, Edward Napierala wrote:
>> It does, and that case might work - I'm not sure, but it might.  But what
>> happens afterwards, after the syscall that triggered the mount completes?
>> You would still have a shell with cwd in that dir, now covered by another
>> filesystem.  Autofs doesn't do anything to "lift" the process to the newly
>> mounted filesystem root.
> The change of the current directory should have already triggered the action,
> because it was preceeded by lookup.  At least this is my understanding of
> the flow.

>From the earlier example I can only conclude that autofs does NOT do a mount on
lookup in a sense of *vpp being a root of the mounted filesystem.  My
interpretation is the mounting is done only if there is a VOP_LOOKUP (or
VOP_READDIR) with a mount point as a dvp.

-- 
Andriy Gapon