[PATCH] mtd: Replace the expert mode symbols with a single helper

[Miquel Raynal]

Hi Geert,

geert at linux-m68k.org wrote on Thu, 27 Jan 2022 13:01:18 +0100:

> Hi Miquel,
> 
> On Thu, Jan 27, 2022 at 12:08 PM Miquel Raynal
> <miquel.raynal at bootlin.com> wrote:
> > Reduce the number of exported symbols by replacing:
> > - mtd_expert_analysis_warning (the error string)
> > - mtd_expert_analysis_mode (the boolean)
> > with a single helper:
> > - mtd_check_expert_analysis_mode
> >
> > Calling this helper will both check/return the content of the internal
> > boolean -which is not exported anymore- and as well WARN_ONCE() the
> > user.
> >
> > While on this function, make the error string local to the helper and
> > set it const.
> >
> > Update all the consumers.
> >
> > Suggested-by: Geert Uytterhoeven <geert at linux-m68k.org>
> > Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>  
> 
> Thanks for your patch!
> 
> > --- a/drivers/mtd/mtdcore.c
> > +++ b/drivers/mtd/mtdcore.c
> > @@ -358,6 +358,19 @@ static int mtd_partname_debug_show(struct seq_file *s, void *p)
> >
> >  DEFINE_SHOW_ATTRIBUTE(mtd_partname_debug);
> >
> > +static bool mtd_expert_analysis_mode;
> > +
> > +bool mtd_check_expert_analysis_mode(void)
> > +{
> > +       const char *mtd_expert_analysis_warning =
> > +               "Bad block checks have been entirely disabled.\n"
> > +               "This is only reserved for post-mortem forensics and debug purposes.\n"
> > +               "Never enable this mode if you do not know what you are doing!\n";
> > +
> > +       return WARN_ONCE(mtd_expert_analysis_mode, mtd_expert_analysis_warning);
> > +}
> > +EXPORT_SYMBOL_GPL(mtd_check_expert_analysis_mode);  
> 
> Please put this inside #ifndef CONFIG_DEBUG_FS, as it wastes
> 176 bytes for the message, and probably the same for the WARN_ONCE(),
> for production kernels.

Yes I will do that. I sent this version before seeing your first answer
about the #ifdef request and arguing about it.

> 
> > +
> >  static struct dentry *dfs_dir_mtd;
> >
> >  static void mtd_debugfs_populate(struct mtd_info *mtd)  
> 
> > --- a/include/linux/mtd/mtd.h
> > +++ b/include/linux/mtd/mtd.h
> > @@ -711,7 +711,6 @@ static inline int mtd_is_bitflip_or_eccerr(int err) {
> >
> >  unsigned mtd_mmap_capabilities(struct mtd_info *mtd);
> >
> > -extern char *mtd_expert_analysis_warning;
> > -extern bool mtd_expert_analysis_mode;
> > +bool mtd_check_expert_analysis_mode(void);  
> 
> #ifdef CONFIG_DEBUG_FS
> bool mtd_check_expert_analysis_mode(void);
> #else
> static inline bool mtd_check_expert_analysis_mode(void) { return false; }
> #endif
> 
> >
> >  #endif /* __MTD_MTD_H__ */  
> 
> Gr{oetje,eeting}s,
> 
>                         Geert
> 
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert at linux-m68k.org
> 
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
>                                 -- Linus Torvalds


Thanks,
Miquèl