Looks good

Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>

On Fri, 2019-02-01 at 21:50 +0100, David Kozub wrote:
> response_get_token had already been in place, its functionality had
> been duplicated within response_get_{u64,bytestring} with the same error
> handling. Unify the handling by reusing response_get_token within the
> other functions.
> 
> Co-authored-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
> Signed-off-by: David Kozub <zub@linux.fjfi.cvut.cz>
> Signed-off-by: Jonas Rabenstein <jonas.rabenstein@studium.uni-erlangen.de>
> Reviewed-by: Scott Bauer <sbauer@plzdonthack.me>
> ---
>  block/sed-opal.c | 46 +++++++++++++++-------------------------------
>  1 file changed, 15 insertions(+), 31 deletions(-)
> 
> diff --git a/block/sed-opal.c b/block/sed-opal.c
> index 537cd73ea88a..1332547e5a99 100644
> --- a/block/sed-opal.c
> +++ b/block/sed-opal.c
> @@ -889,27 +889,19 @@ static size_t response_get_string(const struct parsed_resp *resp, int n,
>  				  const char **store)
>  {
>  	u8 skip;
> -	const struct opal_resp_tok *token;
> +	const struct opal_resp_tok *tok;
>  
>  	*store = NULL;
> -	if (!resp) {
> -		pr_debug("Response is NULL\n");
> -		return 0;
> -	}
> -
> -	if (n >= resp->num) {
> -		pr_debug("Response has %d tokens. Can't access %d\n",
> -			 resp->num, n);
> +	tok = response_get_token(resp, n);
> +	if (IS_ERR(tok))
>  		return 0;
> -	}
>  
> -	token = &resp->toks[n];
> -	if (token->type != OPAL_DTA_TOKENID_BYTESTRING) {
> +	if (tok->type != OPAL_DTA_TOKENID_BYTESTRING) {
>  		pr_debug("Token is not a byte string!\n");
>  		return 0;
>  	}
>  
> -	switch (token->width) {
> +	switch (tok->width) {
>  	case OPAL_WIDTH_TINY:
>  	case OPAL_WIDTH_SHORT:
>  		skip = 1;
> @@ -925,37 +917,29 @@ static size_t response_get_string(const struct parsed_resp *resp, int n,
>  		return 0;
>  	}
>  
> -	*store = token->pos + skip;
> -	return token->len - skip;
> +	*store = tok->pos + skip;
> +	return tok->len - skip;
>  }
>  
>  static u64 response_get_u64(const struct parsed_resp *resp, int n)
>  {
> -	if (!resp) {
> -		pr_debug("Response is NULL\n");
> -		return 0;
> -	}
> +	const struct opal_resp_tok *tok;
>  
> -	if (n >= resp->num) {
> -		pr_debug("Response has %d tokens. Can't access %d\n",
> -			 resp->num, n);
> +	tok = response_get_token(resp, n);
> +	if (IS_ERR(tok))
>  		return 0;
> -	}
>  
> -	if (resp->toks[n].type != OPAL_DTA_TOKENID_UINT) {
> -		pr_debug("Token is not unsigned it: %d\n",
> -			 resp->toks[n].type);
> +	if (tok->type != OPAL_DTA_TOKENID_UINT) {
> +		pr_debug("Token is not unsigned int: %d\n", tok->type);
>  		return 0;
>  	}
>  
> -	if (!(resp->toks[n].width == OPAL_WIDTH_TINY ||
> -	      resp->toks[n].width == OPAL_WIDTH_SHORT)) {
> -		pr_debug("Atom is not short or tiny: %d\n",
> -			 resp->toks[n].width);
> +	if (tok->width != OPAL_WIDTH_TINY && tok->width != OPAL_WIDTH_SHORT) {
> +		pr_debug("Atom is not short or tiny: %d\n", tok->width);
>  		return 0;
>  	}
>  
> -	return resp->toks[n].stored.u;
> +	return tok->stored.u;
>  }
>  
>  static bool response_token_matches(const struct opal_resp_tok *token, u8 match)