Re: [PATCH 12/15] tty: convert THROTTLE constants into enum

[Ilpo Järvinen]

On Tue, 19 Sep 2023, Jiri Slaby (SUSE) wrote:

> And make an explicit constant for zero too. This allows for easier type
> checking of the parameter.
> 
> Note: tty_struct::flow_change is kept as int because include/tty.h
> (tty_struct) doesn't see tty/tty.h (this enum).

And it cannot moved there because of what?

-- 
 i.


> Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
> ---
>  drivers/tty/tty.h       | 13 +++++++++----
>  drivers/tty/tty_ioctl.c |  2 +-
>  2 files changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/tty/tty.h b/drivers/tty/tty.h
> index 50862f98273e..93cf5ef1e857 100644
> --- a/drivers/tty/tty.h
> +++ b/drivers/tty/tty.h
> @@ -41,15 +41,20 @@ enum {
>  };
>  
>  /* Values for tty->flow_change */
> -#define TTY_THROTTLE_SAFE	1
> -#define TTY_UNTHROTTLE_SAFE	2
> +enum tty_flow_change {
> +	TTY_FLOW_NO_CHANGE,
> +	TTY_THROTTLE_SAFE,
> +	TTY_UNTHROTTLE_SAFE,
> +};
>  
> -static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
> +static inline void __tty_set_flow_change(struct tty_struct *tty,
> +					 enum tty_flow_change val)
>  {
>  	tty->flow_change = val;
>  }
>  
> -static inline void tty_set_flow_change(struct tty_struct *tty, int val)
> +static inline void tty_set_flow_change(struct tty_struct *tty,
> +				       enum tty_flow_change val)
>  {
>  	tty->flow_change = val;
>  	smp_mb();
> diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
> index 42c793e9d131..4b499301a3db 100644
> --- a/drivers/tty/tty_ioctl.c
> +++ b/drivers/tty/tty_ioctl.c
> @@ -104,7 +104,7 @@ void tty_unthrottle(struct tty_struct *tty)
>  	if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
>  	    tty->ops->unthrottle)
>  		tty->ops->unthrottle(tty);
> -	tty->flow_change = 0;
> +	tty->flow_change = TTY_FLOW_NO_CHANGE;
>  	up_write(&tty->termios_rwsem);
>  }
>  EXPORT_SYMBOL(tty_unthrottle);
>