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Date:   Thu, 16 Jan 2020 10:47:34 -0800
From:   Ira Weiny <ira.weiny@intel.com>
To:     Jan Kara <jack@suse.cz>
Cc:     linux-kernel@vger.kernel.org,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Chinner <david@fromorbit.com>,
        Christoph Hellwig <hch@lst.de>,
        "Theodore Y. Ts'o" <tytso@mit.edu>, linux-ext4@vger.kernel.org,
        linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [RFC PATCH V2 05/12] fs: remove unneeded IS_DAX() check
Message-ID: <20200116184733.GD24522@iweiny-DESK2.sc.intel.com>
References: <20200110192942.25021-1-ira.weiny@intel.com>
 <20200110192942.25021-6-ira.weiny@intel.com>
 <20200116093807.GB8446@quack2.suse.cz>
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On Thu, Jan 16, 2020 at 10:38:07AM +0100, Jan Kara wrote:
> On Fri 10-01-20 11:29:35, ira.weiny@intel.com wrote:
> > From: Ira Weiny <ira.weiny@intel.com>
> > 
> > The IS_DAX() check in io_is_direct() causes a race between changing the
> > DAX mode and creating the iocb flags.
> > 
> > Remove the check because DAX now emulates the page cache API and
> > therefore it does not matter if the file mode is DAX or not when the
> > iocb flags are created.
> > 
> > Signed-off-by: Ira Weiny <ira.weiny@intel.com>
> 
> The patch looks good to me. You can add:
> 
> Reviewed-by: Jan Kara <jack@suse.cz>

Thanks,
Ira

> 
> 								Honza
> 
> > ---
> >  include/linux/fs.h | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/include/linux/fs.h b/include/linux/fs.h
> > index d7584bcef5d3..e11989502eac 100644
> > --- a/include/linux/fs.h
> > +++ b/include/linux/fs.h
> > @@ -3365,7 +3365,7 @@ extern int file_update_time(struct file *file);
> >  
> >  static inline bool io_is_direct(struct file *filp)
> >  {
> > -	return (filp->f_flags & O_DIRECT) || IS_DAX(filp->f_mapping->host);
> > +	return (filp->f_flags & O_DIRECT);
> >  }
> >  
> >  static inline bool vma_is_dax(struct vm_area_struct *vma)
> > -- 
> > 2.21.0
> > 
> -- 
> Jan Kara <jack@suse.com>
> SUSE Labs, CR