From mboxrd@z Thu Jan  1 00:00:00 1970
From: hooanon05@yahoo.co.jp
Subject: Re: [RFC] Union mounts/writable overlays design
Date: Mon, 12 Oct 2009 14:19:14 +0900
Message-ID: <7347.1255324754@jrobl>
References: <20091001145547.GA29152@shell> <15604.1254497442@jrobl> <20091011014339.GB12667@shell>
Cc: Jan Blunck <jblunck@suse.de>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Christoph Hellwig <hch@infradead.org>,
	Andy Whitcroft <apw@canonical.com>,
	Scott James Remnant <scott@canonical.com>,
	Sandu Popa Marius <sandupopamarius@gmail.com>,
	Jan Rekorajski <baggins@sith.mimuw.edu.pl>,
	Arnd Bergmann <arnd@arndb.de>,
	Vladimir Dronnikov <dronnikov@gmail.com>,
	Felix Fietkau <nbd@openwrt.org>, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: Valerie Aurora <vaurora@redhat.com>
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Valerie Aurora:
> In writable overlays, every directory will be copied up to the top
> writable overlay, so /u and /u/usr will both have the same st_dev.
> The copy up happens on lookup, so a stat() will trigger this copy up.
> A directory and a regular file in it will have different st_dev's,
> though.  Can you foresee any problems with that?

You're right.
I was confused with another implementation of UnionMount, sorry.
I think I had to sleep well.


J. R. Okajima