Re: [patch 4/8] fs, exportfs: Add export_encode_inode_fh helper

From: Cyrill Gorcunov <gorcunov@openvz.org>
To: "J. Bruce Fields" <bfields@fieldses.org>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	Al Viro <viro@zeniv.linux.org.uk>,
	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>
Subject: Re: [patch 4/8] fs, exportfs: Add export_encode_inode_fh helper
Date: Mon, 20 Aug 2012 23:06:06 +0400	[thread overview]
Message-ID: <20120820190606.GE27443@moon> (raw)
In-Reply-To: <20120820183225.GB4911@fieldses.org>

On Mon, Aug 20, 2012 at 02:32:25PM -0400, J. Bruce Fields wrote:
> On Mon, Aug 20, 2012 at 08:33:38PM +0400, Cyrill Gorcunov wrote:
> > On Mon, Aug 20, 2012 at 07:49:23PM +0530, Aneesh Kumar K.V wrote:
> > > Cyrill Gorcunov <gorcunov@openvz.org> writes:
> > > 
> > > > To provide fsnotify object inodes being watched without
> > > > binding to alphabetical path we need to encode them with
> > > > exportfs help. This patch adds a helper which operates
> > > > with plain inodes directly.
> > > 
> > > doesn't name_to_handle_at()  work for you ? It also allows to get a file
> > > handle using file descriptor.
> > 
> > Hi, sorry for dealy. Well, the last idea is to get rid of this helper,
> > I've sent out an updated version where ino+dev is only printed.
> 
> I don't understand how ino and dev are useful to you, though, if you're
> still hoping to be able to look up inodes using this information later
> on.

Hi Bruce, I believe having ino+dev is better than nothing. Otherwise we
simply have no clue which targets are bound to inotify mark. Sometime
(!) we can try to generate fhandle in userspace from this ino+dev bundle
and then open the target file.

	Cyrill