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Date:   Wed, 10 Jul 2019 13:15:39 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Jan Kara <jack@suse.cz>
Cc:     Dan Williams <dan.j.williams@intel.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Boaz Harrosh <openosd@gmail.com>,
        stable <stable@vger.kernel.org>,
        Robert Barror <robert.barror@intel.com>,
        Seema Pandit <seema.pandit@intel.com>,
        linux-nvdimm <linux-nvdimm@lists.01.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] dax: Fix missed PMD wakeups
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On Wed, Jul 10, 2019 at 09:02:04PM +0200, Jan Kara wrote:
> +#define DAX_ENTRY_CONFLICT dax_make_entry(pfn_to_pfn_t(1), DAX_EMPTY)

I was hoping to get rid of DAX_EMPTY ... it's almost unused now.  Once
we switch to having a single DAX_LOCK value instead of a single bit,
I think it can go away, freeing up two bits.

If you really want a special DAX_ENTRY_CONFLICT, I think we can make
one in the 2..4094 range.

That aside, this looks pretty similar to the previous patch I sent, so
if you're now happy with this, let's add

#define XA_DAX_CONFLICT_ENTRY xa_mk_internal(258)

to xarray.h and do it that way?