| This way you have to trust userland passes wired memory. I'd instead
| lock the memory myself on driver side using uvm_vslock(9). You'll need 
to
| uvm_vsunlock(9) it after you're done with the buffer, of course - 
easy,
| if your ioctl() call blocks.

Thanks a lot! This is exactly what I was looking for. Locking memory on
the driver side is surely a far better solution than locking it in the
userland! The ioctl is blocking so there's no problem with this 
solution.

Thanks again,
Damien Bergamini
damien.bergamini [at] free.fr