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Date: Fri, 20 Nov 2015 03:24:53 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
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Subject: Re: [RFC] readlink()-related oddities
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On Thu, Nov 19, 2015 at 07:16:32PM -0800, Linus Torvalds wrote:

> .. it's not necessarily just readlink() either. I still think it might
> be a perfectly fine idea to allow non-directories to act as
> directories in some case (by exposing "readdir" and "lookup").

As soon as we expose ->lookup(), we are in for serious PITA with locking.
Please, don't.  The situation is convoluted enough as it is; playing with
parallel lookups is going to be interesting in itself and I'd rather not
mix it with attempts to accomodate for hybrid objects (e.g. something
with children and more than one parent, etc.), especially since I'm not
sure the latter can be done without major pain.