From mboxrd@z Thu Jan  1 00:00:00 1970
From: Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: [PATCH 0/6] ovl: consistent_fd feature
Date: Fri, 7 Apr 2017 11:56:08 +0200
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On Fri, Apr 7, 2017 at 11:32 AM, Miklos Szeredi <miklos@szeredi.hu> wrote:
> On Thu, Apr 6, 2017 at 6:25 PM, Amir Goldstein <amir73il@gmail.com> wrote:

> When renaming a lower/merged directory or lower non-directory, always
> add back-redirect pointer to moved object pointing to original
> location, as well as forward-redirect to whiteout at original location
> pointing to new location.   Possibly could do both with file handle.
> Whenever either is moved/created/removed pointers need to be updated.
> Hard linking a copied up file would result in duplication of the
> forward pointers.  Solves the nfs export case, since we can always
> find new location of objects based on location on lower layer.

This breaks when an ancestor of a forward-redirect is moved/removed.

A linked list would still work, but all these are bit fragile.  I feel
it's better to keep this sort of info out-of-band.

Thanks,
Miklos