Re: module references

[Marco Gerards <metgerards@student.han.nl>]

Hollis Blanchard <hollis@penguinppc.org> writes:

> Right now I'm getting a lot of these:
> 	../fs/affs.c: In function `grub_mod_init':
> 	../fs/affs.c:556: warning: unused parameter `mod'
> ... in fact, one for every GRUB_MOD_INIT in fs/ and partmap/, it seems.

Right.  `my_mod' is used by the filesystems, but not used from INIT.

> This led me to examine the module reference counting system. Most
> filesystems don't do anything more than set a "my_mod" global
> variable, and never use it. fat.c, on the other hand, seems to
> actually be trying to use a refcount.

They do use it.  When opening a file the reference is increased so the
user can't remove the filesystem module until the file is closed.  If
this is not implemented this way, it's a bug.

> Are modules ever automatically unloaded? When? If so, we need a lot
> more reference counting. If not, we've got some unnecessary complexity
> we should remove.

It's done so you can not remove a module that is in use by GRUB or
another module.  For example when you open a file for a long time.

--
Marco