From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm@digeo.com>
Subject: Re: [Fwd: [Bug 136] New: FSID returned from statvfs always 0]
Date: Tue, 17 Dec 2002 21:15:00 -0800
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Cc: "H. Peter Anvin" <hpa@zytor.com>, linux-fsdevel@vger.kernel.org
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To: Andries Brouwer <aebr@win.tue.nl>
List-Id: linux-fsdevel.vger.kernel.org

Andries Brouwer wrote:
> 
> On Mon, Dec 09, 2002 at 02:15:12PM -0800, H. Peter Anvin wrote:
> 
> > > The general idea is that f_fsid contains some random stuff such that
> > > the pair (f_fsid,ino) uniquely determines a file.
> 
> > This, of course, is the exact POSIX definition of the st_dev part of
> > struct stat: (st_dev, st_ino) uniquely identifies the file.
> 
> Yes, but the difference is that (st_dev, st_ino) only identifies
> the file within a single machine, and may stop working when you
> have NFS mounts.
> 
> The traditional implementations use st_dev and NFS filehandles
> and a hash of the filesystem type.
> 

If this feature is to have any value, should not the fsid remain stable
as the disk gets moved around the machine?

I'm not sure I saw sufficient solidity in this discussion to be able to
generate&justify a patch.