Re: [PATCH] cowlinks v2

[Jamie Lokier]

Eric W. Biederman wrote:
> > The addictive thing about the prototype implementation was that you
> > could do ``ln --cow / /some/other/directory'' and you would have an
> > atomic snapshot of your filesystem.  Definitely not a feature for the
> > first implementation but certainly something to dream about.
> 
> Addictive but broken by design.  If any of the files inside your
> directory tree have hard links outside of the tree there is no way
> short of recursing through all of the subdirectories directories to
> tell if a given inode has is in use.  Except in the special case
> where you are taking a cow copy of the entire filesystem.  At which
> point a magic mount option is likely a better interface.

I don't understand this explanation.  Can you explain again?  What is
the problem with inodes being in use?

-- Jamie
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/