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From:   Dan Williams <dan.j.williams@intel.com>
Date:   Mon, 23 Aug 2021 14:15:47 -0700
Message-ID: <CAPcyv4hezYrurYEsBZ-7obnNYr0qbdtw+k0NBviOqqgT70ZL+w@mail.gmail.com>
Subject: Re: [PATCH 7/9] dax: stub out dax_supported for !CONFIG_FS_DAX
To:     Christoph Hellwig <hch@lst.de>
Cc:     Vishal Verma <vishal.l.verma@intel.com>,
        Dave Jiang <dave.jiang@intel.com>,
        Mike Snitzer <snitzer@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        linux-xfs <linux-xfs@vger.kernel.org>,
        Linux NVDIMM <nvdimm@lists.linux.dev>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        linux-ext4 <linux-ext4@vger.kernel.org>
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On Mon, Aug 23, 2021 at 5:43 AM Christoph Hellwig <hch@lst.de> wrote:
>
> dax_supported calls into ->dax_supported which checks for fsdax support.
> Don't bother building it for !CONFIG_FS_DAX as it will always return
> false.
>

Looks good, modulo formatting question below:

Reviewed-by: Dan Williams <dan.j.williams@intel.com>

> diff --git a/include/linux/dax.h b/include/linux/dax.h
> index 0a3ef9701e03..32dce5763f2c 100644
> --- a/include/linux/dax.h
> +++ b/include/linux/dax.h
[..]
> @@ -149,6 +144,13 @@ static inline bool bdev_dax_supported(struct block_device *bdev,
>
>  #define generic_fsdax_supported                NULL
>
> +static inline bool dax_supported(struct dax_device *dax_dev,
> +               struct block_device *bdev, int blocksize, sector_t start,
> +               sector_t len)
> +{
> +       return false;
> +}

I've started clang-formatting new dax and nvdimm code:

static inline bool dax_supported(struct dax_device *dax_dev,
                                 struct block_device *bdev, int blocksize,
                                 sector_t start, sector_t len)
{
        return false;
}

...but I also don't mind staying consistent with the surrounding code for now.