How to best overload the fileops ?

[Yuri]

On 08/21/2013 17:10, Mateusz Guzik wrote:
> Short answer is provide epollops with your own fo_close and the rest as
> it is currently in kqueueops. All function are static, but this is not a
> real problem since you have to modify kern_event.c anyway.

This is exactly what this code I am asking about is doing.
kqueueops functions are all static. This modification allows to export 
fileops to child modules.
Since there is nothing similar in the kernel code, I am asking does this 
way look ugly or not.

>
> I don't know how your code looks like in general, so in case its not
> clear, simply wrapping sys_kqueue is inherently racy (some other thread
> may close the fd or even reuse it for something else by the time you try
> to do anything with it), thus modification of current code is
> unavoidable.

No, sys_kqueue calling code is all protected by the lock on this file 
object. So nobody can close or reuse it.

Yuri