Re: [PATCH v5 3/4] zram: validate parameters in each backend's setup_params

On (26/08/03 22:12), Haoqin Huang wrote:
[..]
>  static int setup_params_842(struct zcomp_params *params)
>  {
> +	if (params->dict_sz) {
> +		pr_err("842: dictionary is not supported\n");
> +		return -EOPNOTSUPP;
> +	}
> +	if (params->level != ZCOMP_PARAM_NOT_SET) {
> +		pr_err("842: compression level is not supported\n");
> +		return -EOPNOTSUPP;
> +	}
>  	return 0;
>  }
[..]
>  static int deflate_setup_params(struct zcomp_params *params)
>  {
> +	if (params->dict_sz) {
> +		pr_err("deflate: dictionary is not supported\n");
> +		return -EOPNOTSUPP;
> +	}
> +
>  	if (params->level == ZCOMP_PARAM_NOT_SET)
>  		params->level = Z_DEFAULT_COMPRESSION;
> +	else if (params->level < Z_DEFAULT_COMPRESSION ||
> +		 params->level > Z_BEST_COMPRESSION) {
> +		pr_err("deflate: invalid compression level %d\n", params->level);
> +		return -EINVAL;
> +	}

This is purely optional, if you add per-backend pr_fmt() with backend
name e.g. "zstd:","lz4:" and so on (in a separate patch) then you don't
need to explicitly prefix every pr_err().