Re: [PATCH v3 06/20] firmware: use helpers for setting up a temporary cache timeout

[Greg KH]

On Sat, Mar 10, 2018 at 06:14:47AM -0800, Luis R. Rodriguez wrote:
> We only use the timeout for the firmware fallback mechanism
> except for trying to set the timeout during the cache setup
> for resume/suspend. For those cases, setting the timeout should
> be a no-op, so just reflect this in code by adding helpers for it.
> 
> This change introduces no functional changes.
> 
> Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
> Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx>
> ---
>  drivers/base/firmware_loader.c | 49 ++++++++++++++++++++++++++----------------
>  1 file changed, 30 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/base/firmware_loader.c b/drivers/base/firmware_loader.c
> index 59dba794ce1a..2d819875348d 100644
> --- a/drivers/base/firmware_loader.c
> +++ b/drivers/base/firmware_loader.c
> @@ -191,13 +191,6 @@ static inline bool fw_is_builtin_firmware(const struct firmware *fw)
>  }
>  #endif
>  
> -static int loading_timeout = 60;	/* In seconds */
> -
> -static inline long firmware_loading_timeout(void)
> -{
> -	return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
> -}
> -
>  static void fw_state_init(struct fw_priv *fw_priv)
>  {
>  	struct fw_state *fw_st = &fw_priv->fw_st;
> @@ -282,6 +275,32 @@ static const struct firmware_fallback_config fw_fallback_config = {
>  	.force_sysfs_fallback = IS_ENABLED(CONFIG_FW_LOADER_USER_HELPER_FALLBACK),
>  };
>  
> +static int old_timeout;
> +static int loading_timeout = 60;	/* In seconds */
> +
> +static inline long firmware_loading_timeout(void)
> +{
> +	return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
> +}
> +
> +/*
> + * use small loading timeout for caching devices' firmware because all these
> + * firmware images have been loaded successfully at lease once, also system is
> + * ready for completing firmware loading now. The maximum size of firmware in
> + * current distributions is about 2M bytes, so 10 secs should be enough.
> + */
> +static void fw_fallback_set_cache_timeout(void)
> +{
> +	old_timeout = loading_timeout;
> +	loading_timeout = 10;
> +}
> +
> +/* Restores the timeout to the value last configured during normal operation */
> +static void fw_fallback_set_default_timeout(void)
> +{
> +	loading_timeout =  old_timeout;

extra space?

Yeah, nit, I know :)