Re: Where did vm_operations_struct->unmap in 2.4.0 go?

[Keith Owens]

On Sun, 14 Jan 2001 13:47:29 -0800 (PST), 
Linus Torvalds <[e-mail]> wrote:
>On Sun, 14 Jan 2001, David Woodhouse wrote:
>> That's the one flaw in the inter_module_get() stuff - we could do with a
>> way to put entries in the table at _compile_ time, rather than _only_ at
>> run time. 
>
>Ok, I can buy that. Not having to initialize explicitly would be nice, but
>if so we should make module loading do it automatically too ...

It might be nice but it is also expensive.  Adding static
inter_module_xxx tables requires

* changes to linux/modules.h to define the new table format and
* changes to vmlinux.lds for _every_ architecture to bring all the
  static tables together in vmlinux and
* new initialisation code in module.c to read and load all the static
  tables at boot time and
* extra code in modutils to find any static tables in modules and
* an extension to struct modules to let modutils pass information about
  the static tables to the kernel and
* the kernel code will only work with an upgraded modutils.

That is a lot of work for a very few special cases.  OTOH, you could
just add a few lines of __initcall code in two source files (which I
did when I wrote inter_module_xxx) and swap the order of 3 lines in
drivers/mtd/Makefile.  Guess which alternative I am going for?

IMHO any automatic method that relies on ELF sections and/or modutils
support is the wrong approach, it is a complex solution with external
dependencies when we already have a simple solution with no external
dependencies.  What next, static tables for file system registration,
for device registration?