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Date: Mon, 26 Mar 2012 09:30:28 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Christoph Hellwig <hch@infradead.org>, viro@zeniv.linux.org.uk,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Trond.Myklebust@netapp.com, sfrench@samba.org, sage@newdream.net,
        ericvh@gmail.com, mszeredi@suse.cz
Subject: Re: [PATCH 03/25] vfs: split __dentry_open()
Message-ID: <20120326133028.GA8436@infradead.org>
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On Mon, Mar 26, 2012 at 03:22:09PM +0200, Miklos Szeredi wrote:
> > I think the O_DIRECT checks should move out of the VFS. ??The direct I/O
> > method isn't called from the VFS anywhere, but just from the
> > generic_file_* routines in filemap.c, which suggest doing the O_DIRECT
> > check in there as well.
> 
> Returning the error at the earliest opportunity (from open as opposed
> to read/write) makes sense.  Given that some apps may actually rely on
> the return value from open to verify O_DIRECT support, it doesn't seem
> to be a good idea to move the checks to read/write.

I'm fine with keeping it in open, bu it should be in generic_file_open,
not in the VFS (and yeah, generic_file_open is in open.c not filemap.c
where it should be, sorry)