dev_set_allmulti — update allmulti count on a device
void dev_set_allmulti (
struct net_device * dev, int inc)
;
Add or remove reception of all multicast frames to a device. While the
count in the device remains above zero the interface remains listening
to all interfaces. Once it hits zero the device reverts back to normal
filtering operation. A negative inc
value is used to drop the counter
when releasing a resource needing all multicasts.