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Date: Tue, 27 Jun 2006 08:50:33 +0100
From: Christoph Hellwig <hch@infradead.org>
To: Ingo Molnar <mingo@elte.hu>
Cc: Christoph Hellwig <hch@infradead.org>,
       Steven Whitehouse <swhiteho@redhat.com>,
       Linus Torvalds <torvalds@osdl.org>,
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       Patrick Caulfield <pcaulfie@redhat.com>,
       Kevin Anderson <kanderso@redhat.com>, Andrew Morton <akpm@osdl.org>,
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Subject: Re: GFS2 and DLM
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On Mon, Jun 26, 2006 at 10:58:24PM +0200, Ingo Molnar wrote:
> i think you might be missing that GFS does cross-node locking in 
> readlink too. (OCFS2 does not do it because it apparently does not care 
> about cross-node atime correctness here it seems.) So GFS simply cannot 
> use generic_readlink()!

Please read the code before giving such useless comments.  ->follow_link
needs exactly the same locking as ->readlink.  The whole point of
using generic_readlink is to avoid having the filesystem reimplement
almost the same code twice, once copying to a kernel buffer and once to
a user buffer.