wwan: core: no more hold netdev ops owning module

The WWAN netdev ops owner holding was used to protect from the
unexpected memory disappear. This approach causes a dependency cycle
(driver -> core -> driver) and effectively prevents a WWAN driver
unloading. E.g. WWAN hwsim could not be unloaded until all simulated
devices are removed:

~# modprobe wwan_hwsim devices=2
~# lsmod | grep wwan
wwan_hwsim             16384  2
wwan                   20480  1 wwan_hwsim
~# rmmod wwan_hwsim
rmmod: ERROR: Module wwan_hwsim is in use
~# echo > /sys/kernel/debug/wwan_hwsim/hwsim0/destroy
~# echo > /sys/kernel/debug/wwan_hwsim/hwsim1/destroy
~# lsmod | grep wwan
wwan_hwsim             16384  0
wwan                   20480  1 wwan_hwsim
~# rmmod wwan_hwsim

For a real device driver this will cause an inability to unload module
until a served device is physically detached.

Since the last commit we are removing all child netdev(s) when a driver
unregister the netdev ops. This allows us to permit the driver
unloading, since any sane driver will call ops unregistering on a device
deinitialization. So, remove the holding of an ops owner to make it
easier to unload a driver module. The owner field has also beed removed
from the ops structure as there are no more users of this field.

Signed-off-by: Sergey Ryazanov <[email protected]>
Reviewed-by: Loic Poulain <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

0 files changed, 0 insertions, 0 deletions