[PATCH 3/3] nvme: add 'queue_if_no_path' sysfs attribute

[Christoph Hellwig]

On Mon, Oct 05, 2020 at 11:42:56AM +0200, Hannes Reinecke wrote:
> Add a sysfs attribute 'queue_if_no_path' to allow the admin to
> view and modify the 'queue_if_no_path' flag.

ok, here it gets added.  I think this needs to be folded into the
previous patch.

> +{
> +	struct nvme_ns_head *head = dev_to_ns_head(dev);
> +	int queue_if_no_path, err;
> +
> +	err = kstrtoint(buf, 10, &queue_if_no_path);
> +	if (err)
> +		return -EINVAL;
> +
> +	else if (queue_if_no_path <= 0)

I think this needs to use kstrtobool..

>  #ifdef CONFIG_NVME_MULTIPATH
>  	&dev_attr_ana_grpid.attr,
>  	&dev_attr_ana_state.attr,
> @@ -3381,6 +3411,10 @@ static umode_t nvme_ns_id_attrs_are_visible(struct kobject *kobj,
>  		if (!memchr_inv(ids->eui64, 0, sizeof(ids->eui64)))
>  			return 0;
>  	}
> +	if (a == &dev_attr_queue_if_no_path.attr) {
> +		if (dev_to_disk(dev)->fops == &nvme_fops)
> +			return 0;
> +	}
>  #ifdef CONFIG_NVME_MULTIPATH

The attribute only makes sense for the multipathing code, so it should
be under CONFIG_NVME_MULTIPATH.