Re: [PATCH] module: make it clearer when we're handling kallsyms symbols vs exported symbols

[Jessica Yu]

+++ Miroslav Benes [22/11/18 11:19 +0100]:
> On Wed, 21 Nov 2018, Jessica Yu wrote:
>
> > The module loader internally works with both exported symbols
> > represented as struct kernel_symbol, as well as Elf symbols from a
> > module's symbol table. It's hard to distinguish sometimes which type of
> > symbol we're handling given that some helper function names are not
> > consistent or helpful. Take get_ksymbol() for instance - are we
> > looking for an exported symbol or a kallsyms symbol here? Or symname()
> > and kernel_symbol_name() - which function handles an exported symbol and
> > which one an Elf symbol?
> >
> > Clean up and unify the function naming scheme a bit to make it clear
> > which kind of symbol we're handling. This change only affects static
> > functions internal to the module loader.
> >
> > Signed-off-by: Jessica Yu <jeyu@xxxxxxxxxx>
>
> Great. It should help a lot. Pity we cannot rename find_symbol() as well.
>
> I have only a naming nit. I think it is nice to have
> <verb>_exported_<noun> convention. New kallsyms_ names don't hold it
> though. Wouldn't it be better to be consistent and have
> find_kallsyms_symbol() instead of kallsyms_find_symbol()? Or we could do
> the opposite and have a "namespace" prefix first. That is,
> exported_<verb>_<noun>. However, I don't like it that much.
>
> To be honest, your approach may be the best in the end.
>
> What do you think?

Hi Miroslav, thank you for the comment!

Yeah, that bothered me partially too. And a lot of existing helper
functions in the module loader already have a <verb>_ type prefix.

Hm, how about we use <symbol_type>_* prefixes if we are just extracting a
value, and <verb>_* prefixes for functions actually performing an
action? 

Kallsyms:

  kallsyms_symbol_name()
  kallsyms_symbol_value()
  
  find_kallsyms_symbol()
  find_kallsyms_symbol_value()

  etc.

Exported syms:

  kernel_symbol_name()
  kernel_symbol_value()
  
  lookup_exported_symbol()
  check_exported_symbol()

  etc.

I had left the kernel_symbol_* functions alone since I guess they do
describe what they're handling, they're handling struct kernel_symbol's.
But maybe I will change that to exported_symbol_name() and
exported_symbol_value() to be consistent with the naming scheme..

Thanks!

Jessica