Re: [PATCH 1/2] xfs: cache dax_device lookup result

[Christoph Hellwig <hch@xxxxxx>]

> +	bdev = bt->bt_bdev;
> +	if (!blk_queue_dax(bdev->bd_queue))
> +		return NULL;
> +
> +	if (!bt->bt_daxdev)
> +		bt->bt_daxdev = fs_dax_get_by_host(bdev->bd_disk->disk_name);
> +
> +	return bt->bt_daxdev;

Please do this at mount time.