Re: Revealing unload_lock to everyone

[Keith Owens <kaos@ocs.com.au>]

On Thu, 31 Jan 2002 15:58:17 -0800, 
Dave Hansen <haveblue@us.ibm.com> wrote:
>This came up in a conversation about ieee1394_core.c.  In 2.5.3, the BKL 
>is used to protect a module from being unloaded.  The code looks like this:
>
>         lock_kernel();
>         read_lock(&ieee1394_chardevs_lock);
>         file_ops = ieee1394_chardevs[blocknum].file_ops;
>         module = ieee1394_chardevs[blocknum].module;
>         read_unlock(&ieee1394_chardevs_lock);
>	...
>         INCREF(module);
>         unlock_kernel();
>	
>
>The question is, how can we keep the module from being unloaded between 
>the file_ops assignment, and the INCREF.  Do we have a general purpose 
>way, other than the BKL, to keep a module from being unloaded?  There is 
>unload_lock, but it is static to module.c.  We can always make it 
>global, but is there a better solution?

try_inc_mod_count().