From: Trond Myklebust <trond.myklebust-41N18TsMXrtuMpJDpNschA@public.gmane.org>
Subject: Re: [PATCH 02/18] xstat: Add a pair of system calls to make
 extended file stats available [ver #6]
Date: Sat, 31 Jul 2010 15:03:52 -0400
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Cc: Phil Pishioneri <pgp-8DAjSxpRXgY@public.gmane.org>, Volker.Lendecke-PS7XAnAlDA+VvDNblw4Uiw@public.gmane.org,
	Jeremy Allison <jra-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org>,
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To: Andreas Dilger <adilger-m1MBpc4rdrD3fQ9qLvQP4Q@public.gmane.org>
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On Sat, 2010-07-31 at 12:41 -0600, Andreas Dilger wrote:
> On 2010-07-30, at 12:11, Trond Myklebust wrote:
> > Your Mac has a perfectly functional CIFS client, as do your Linux boxes.
> > They both interoperate just fine with Samba, and would presumably
> > continue to do so if someone were to decide to reuse the ctime field on
> > your Samba box as storage for a create time.
> 
> CIFS doesn't support symlinks (they just appear as the referenced file), so I've had applications that scan the filesystem recurse indefinitely due to symlinked directories on a CIFS share appearing as hard-linked directories on the client.  This doesn't happen when the filesystem is accessed via NFS.

Sigh... So please explain how it would be useful to export that
particular filesystem through _both_ CIFS and NFS?

My point was that in most circumstances you want to export either
through CIFS or through NFS, but very rarely both.

I also made the point that converting ctime into a creation time would
break NFS, but it would be a limited breakage, mainly affecting the
client's ability to detect ACL changes, and possibly causing the inode
to get temporarily updated with stale attribute information on occasion
due to out-of-order RPC replies.

  Trond