From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH -V7 3/9] vfs: Add name to file handle conversion support
Date: Fri, 14 May 2010 19:40:44 +0100
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Cc: Andreas Dilger <andreas.dilger@oracle.com>,
	Neil Brown <neilb@suse.de>,
	Christoph Hellwig <hch@infradead.org>,
	Jonathan Corbet <corbet@lwn.net>,
	Serge Hallyn <serue@us.ibm.com>, linux-fsdevel@vger.kernel.org,
	Steven French <sfrench@us.ibm.com>,
	Philippe Deniel <philippe.deniel@CEA.FR>,
	"linux-kernel@vger.kernel.org Mailinglist"
	<linux-kernel@vger.kernel.org>
To: "Aneesh Kumar K. V" <aneesh.kumar@linux.vnet.ibm.com>
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On Fri, May 14, 2010 at 11:48:24PM +0530, Aneesh Kumar K. V wrote:

> How about
> sys_open_by_handle(int mountdirfd,
>                   struct file_handle __user *ufh, int open_flag)
> 
> and we validate the UUID present in the file_handle by using mountdirfd
> vfsmount. In otherwords we drop the UUID based vfsmount lookup, But
> still add UUID as a part of file handle ?

IDGI.  If you have decided upon the mountdirfd, why bother with rechecking?
You still need to handle the case when fs tells you to take a hike because
fileid was invalid.  What does duplicate uuid check in the kernel buy you?