Re: FMODE_EXEC or alike?

From: Oleg Drokin <green@linuxhacker.ru>
To: Antonio Vargas <windenntw@gmail.com>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: FMODE_EXEC or alike?
Date: Tue, 21 Feb 2006 16:21:59 +0200	[thread overview]
Message-ID: <20060221142159.GI5733@linuxhacker.ru> (raw)
In-Reply-To: <69304d110602210615m491829ccx9ba84edc8dafe1f7@mail.gmail.com>

Hello!

On Tue, Feb 21, 2006 at 03:15:53PM +0100, Antonio Vargas wrote:
> > > We would need to understand whether this is needed by other distributed
> > > filesystems and if so, whether the proposed implementation is suitable and
> > > sufficient.
> > Hmm.... We might possibly want to use that for NFSv4 at some point in
> > order to deny write access to the file to other clients while it is in
> > use.
> When done with regards to failing a write if anyone has mapped the
> file for executing it, or failing the execute if it's open/mmaped for
> write, I can't really see the difference between local, remote and
> clustered filesystems...

Currently this is only possible locally, when both execution and opening
for writing is performed on the same node. Then VFS enforces ETXTBSY.
But if you do exec on one node and open for writing on another,
VFSes on those nodes have no idea on what happens on all other nodes.

Bye,
    Oleg