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From: Al Viro <viro-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
Subject: Re: RFC: renameat(): Add a RENAME_REMOVE flag to unlink hardlinks
Date: Sat, 22 Nov 2014 01:50:10 +0000
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On Sat, Nov 22, 2014 at 01:29:05AM +0000, P=E1draig Brady wrote:

> > I assume that VFS can handle this correctly if it wants to.
>=20
> I was assuming there was a way to distinguish directory entries,
> and that's what should be checked first, which is what my
> psuedo code patch attempted to show.

There isn't, in general.  Sure, if you get the same struct dentry * fro=
m
both lookups, it's the same one.  But it's not guaranteed to be true on
every fs out there if those are non-directories (and for directories th=
ere's
no multiple hardlinks in the first place).