Hard module dependencies

[Andy Whitcroft]

On Tue, Oct 06, 2009 at 10:12:57AM -0600, Tim Gardner wrote:
> Andy - How about something like this? I need to test some boundary
> conditions (like what happens if the target is not a module, etc), and
> flesh out the commit log, perhaps add some comments to the function.
> -- 
> Tim Gardner tim.gardner at canonical.com

> From 31223d1147dc4d96a70688b5987e9cb63b579f62 Mon Sep 17 00:00:00 2001
> From: Tim Gardner <tim.gardner at canonical.com>
> Date: Tue, 6 Oct 2009 08:52:38 -0600
> Subject: [PATCH 1/2] UBUNTU: [Upstream] Added module_depends()
> 
> Signed-off-by: Tim Gardner <tim.gardner at canonical.com>
> ---
>  include/linux/module.h |   19 +++++++++++++++++++
>  1 files changed, 19 insertions(+), 0 deletions(-)
> 
> diff --git a/include/linux/module.h b/include/linux/module.h
> index 098bdb7..8827da5 100644
> --- a/include/linux/module.h
> +++ b/include/linux/module.h
> @@ -703,6 +703,25 @@ static inline void module_remove_modinfo_attrs(struct module *mod)
>  
>  #define __MODULE_STRING(x) __stringify(x)
>  
> +static inline void module_depends(const char *mod_name)
> +{
> +	struct module *mod;
> +
> +	if (mutex_lock_interruptible(&module_mutex) != 0) {
> +		printk(KERN_ERR "%s Could not get module_mutex\n",__func__);
> +		return;
> +	}
> +	mod = find_module(mod_name);
> +	if (!mod) {
> +		mutex_unlock(&module_mutex);
> +		printk(KERN_ERR "%s Could not find module %s\n",__func__,mod_name);
> +		return;
> +	}
> +	if (use_module(THIS_MODULE,mod) <= 0) {
> +		printk(KERN_ERR "%s Could not load module %s\n",__func__,mod_name);
> +	}
> +	mutex_unlock(&module_mutex);
> +}
>  
>  #ifdef CONFIG_GENERIC_BUG
>  int  module_bug_finalize(const Elf_Ehdr *, const Elf_Shdr *,

Looking pretty sensible, how did this fair in testing?

-apw