Avoid directly incrementing next_to_use for multiple reasons. The main
reason being that if we directly increment it then it can attain a state
where it is equal to the ring count. Technically this is a state it
should not be able to reach but the way this is written it now can.
This patch pulls the value off into a register and then increments it
and writes back either the value or 0 depending on if the value is equal
to the ring count.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Kavindya Deegala <kavindya.s.deegala@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
fc4ac67bc9