Re: [PATCH] staging: r8188eu: replace rtw_netdev_priv define with inline function

Greg Kroah-Hartman
2020-08-01T13:13:26Z

On Sat, Aug 01, 2020 at 04:11:38PM +0300, Ivan Safonov wrote:
> On 8/1/20 12:51 PM, Greg Kroah-Hartman wrote:
> > On Sat, Aug 01, 2020 at 12:47:07PM +0300, Ivan Safonov wrote:
> > > The function guarantees type checking of arguments and return value.
> > >
> > > Signed-off-by: Ivan Safonov <insafonov@gmail.com>
> > > ---
> > > drivers/staging/rtl8188eu/include/osdep_service.h | 6 ++++--
> > > 1 file changed, 4 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/staging/rtl8188eu/include/osdep_service.h b/drivers/staging/rtl8188eu/include/osdep_service.h
> > > index 31d897f1d21f..e0ccafdea9cd 100644
> > > --- a/drivers/staging/rtl8188eu/include/osdep_service.h
> > > +++ b/drivers/staging/rtl8188eu/include/osdep_service.h
> > > @@ -71,8 +71,10 @@ struct rtw_netdev_priv_indicator {
> > > };
> > > struct net_device *rtw_alloc_etherdev_with_old_priv(void *old_priv);
> > > -#define rtw_netdev_priv(netdev) \
> > > - (((struct rtw_netdev_priv_indicator *)netdev_priv(netdev))->priv)
> > > +static inline struct adapter *rtw_netdev_priv(struct net_device *dev)
> > > +{
> > > + return (((struct rtw_netdev_priv_indicator *)netdev_priv(dev))->priv);
> > > +}
> > > void rtw_free_netdev(struct net_device *netdev);
> >
> > Is the cast really needed?
>
> (struct rtw_netdev_priv_indicator *) cast needed for access to '->priv'.
>
> The (struct adapter *) return type is a starting point for simplify
> struct adapter *padapter = (struct adapter *)rtw_netdev_priv(dev);
> constructions.

Ah, sorry, missed that I thought this was a cast of netdev_priv(dev)
itself, and not the additional structure.

> >
> > And no blank line before the next function prototype?
>
> In v2.
>
> >
> > And is this really needed? Type checking is already happening as this
> > is a "simple" macro, right?
>
> 1. The flexibility of macros is not needed here.
> 2. The macro silently assigns ->priv to any pointer, while the function
> indicates such a compile-time error.

Ok, put that somewhere in the changelog please, saying how the existing
macro does not provide any error checking.

thanks,

greg k-h