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Date: Fri, 10 Nov 2017 18:23:44 +0100
From: "hch@lst.de" <hch@lst.de>
To: "Fu, Rodney" <rfu@panasas.com>
Cc: "hch@lst.de" <hch@lst.de>,
        "viro@zeniv.linux.org.uk" <viro@zeniv.linux.org.uk>,
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Subject: Re: Provision for filesystem specific open flags
Message-ID: <20171110172344.GA15288@lst.de>
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On Fri, Nov 10, 2017 at 04:49:33PM +0000, Fu, Rodney wrote:
> The kernel prevents unknown open flags from being passed through to the 
> underlying filesystem.  I am wondering if people would be for or against the 
> idea of provisioning some number of bits in the open flags that are opaque to 
> the VFS layer but get passed down to the underlying filesystem?  The motivation 
> would be to allow filesystem specific semantics to be controllable via open, 
> much like the more generic and pre-existing open flags.

Absolutely against.  Open flags need to be defined in common code or
you are in a massive world of trouble.