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Subject: Re: recent nfs change causes autofs regression
From: Trond Myklebust <trond.myklebust@fys.uio.no>
To: Frank van Maarseveen <frankvm@frankvm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Fri, 31 Aug 2007 09:50:12 -0400
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On Fri, 2007-08-31 at 15:12 +0200, Frank van Maarseveen wrote:

> IMHO I'd only consider returning EBUSY when trying to mount _exactly_
> the same directory with different flags, not for arbitrary subtrees. The
> client should preferably not be bothered with server side disk
> partitioning (at least not beyond the obvious such as df output).

That is utterly inconsistent and confusing too.

If you have a filesystem "/foo" exported on the server "remote", then
why should

        mount -oro remote:/foo
        mount -orw remote:/foo/a

be allowed, but

        mount -oro remote:/foo
        mount -orw remote:/foo

be forbidden? The caching problems are the same. Telling the admin that
one is safe and the other is not, is just messing with his mind.

Trond