From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cyrill Gorcunov <gorcunov@openvz.org>
Subject: Re: [patch 3/8] procfs: Add ability to plug in auxiliary fdinfo
 providers
Date: Wed, 15 Aug 2012 01:56:16 +0400
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Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Pavel Emelyanov <xemul@parallels.com>,
	James Bottomley <jbottomley@parallels.com>,
	Matthew Helsley <matt.helsley@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
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On Tue, Aug 14, 2012 at 10:27:21PM +0100, Al Viro wrote:
> On Tue, Aug 14, 2012 at 11:56:49PM +0400, Cyrill Gorcunov wrote:
> > Al, does the patch below looks better? If so I'll fix up the rest.
> 
> >  struct file_operations {
> >  	struct module *owner;
> > +	struct seq_operations *fdinfo_ops;
> 
> IDGI.  Why on the earth do you need the whole iterator?  All it takes
> is show_fdinfo(struct seq_file *m, struct file *f); have ->show() in
> your iterator (one going through the files) call that sucker for the
> file we are trying to show.
> 
> I think you are severely overdesigning that thing...

Hmm, in very first versions I've been using one ->show method, but
then I thought that this is not very correlate with seq-files idea
where for each record show/next sequence is called. I'll update (this
for sure will make code simplier, and I'll have to check for seq-file
overflow after seq_printf call to not continue printing data for too
long if buffer already out of space).

	Cyrill