Re: [RFC] add kobject to struct module

[Greg KH <greg@kroah.com>]

On Thu, Sep 11, 2003 at 12:32:47AM +0100, Russell King wrote:
> On Tue, Sep 09, 2003 at 03:24:21PM -0700, Greg KH wrote:
> > A while ago we had talked about adding a kobject to struct module.  By
> > doing this we add support for module paramaters and other module info to
> > be exported in sysfs.  So here's a patch that does this that is against
> > 2.6.0-test4 (it applies with some fuzz, sorry.)
> 
> Please excuse my short-sightedness, but I think the following points
> haven't been thought deeply enough:
> 
> - modules which use their parameters on initialisation only once.
>   (eg, 3c59x "full_duplex" parameter)
> 
> - Also, what about module parameters which modules aren't expecting to
>   change beneath themselves? (eg, all the watchdog modules)
> 
> - Are we opening the floodgates for another round of races and driver
>   updates?

If you set the "perm" portion of the module_param() macro to 0, then the
sysfs file will not be created.  That will cause all of the old modules
that use the MODULE_PARAM() macro to not have things change for them, as
they will not be expecting it.

To quote from include/linux/moduleparam.h:
/* This is the fundamental function for registering boot/module
   parameters.  perm sets the visibility in driverfs: 000 means it's
   not there, read bits mean it's readable, write bits mean it's
   writable. */

Sound ok with you?

thanks,

greg k-h