Re: [PATCH-for-4.6 1/6] target: Add target_alloc_session() helper function

[Christoph Hellwig]

> +struct se_session *
> +target_alloc_session(struct se_portal_group *tpg,
> +		     unsigned int tag_num, unsigned int tag_size,
> +		     enum target_prot_op prot_op,
> +		     const char *initiatorname, void *private,
> +		     int (*callback)(struct se_portal_group *,
> +				     struct se_session *, void *))
> +{

I'd much rather have the fabrics drivers call transport_alloc_session_tags
directly from the callback than growing even more arguments here.

> +	struct se_session *sess;
> +
> +	if (tag_num != 0 && !tag_size) {
> +		pr_err("target_alloc_session called with percpu-ida tag_num:"
> +		       " %u, but zero tag_size\n", tag_num);
> +		return ERR_PTR(-EINVAL);
> +	}
> +	if (!tag_num && tag_size) {
> +		pr_err("target_alloc_session called with percpu-ida tag_size:"
> +		       " %u, but zero tag_num\n", tag_size);
> +		return ERR_PTR(-EINVAL);
> +	}

These checks should be in transport_alloc_session_tags.