[NET]: Fix drivers to handle napi_disable() disabling interrupts.

When we add the generic napi_disable_pending() breakout
logic to net_rx_action() it means that napi_disable()
can cause NAPI poll interrupt events to be disabled.

And this is exactly what we want.  If a napi_disable()
is pending, and we are looping in the ->poll(), we want
->poll() event interrupts to stay disabled and we want
to complete the NAPI poll ASAP.

When ->poll() break out during device down was being handled on a
per-driver basis, often these drivers would turn interrupts back on
when '!netif_running()' was detected.

And this would just cause a reschedule of the NAPI ->poll() in the
interrupt handler before the napi_disable() could get in there and
grab the NAPI_STATE_SCHED bit.

The vast majority of drivers don't care if napi_disable() might have
the side effect of disabling NAPI ->poll() event interrupts.  In all
such cases, when a napi_disable() is performed, the driver just
disabled interrupts or is about to.

However there were three exceptions to this in PCNET32, R8169, and
SKY2.  To fix those cases, at the subsequent napi_enable() points, I
added code to ensure that the ->poll() interrupt events are enabled in
the hardware.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by:  Don Fry <pcnet32@verizon.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 5863190894c..af8030981f1 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -2398,6 +2398,8 @@ static void rtl8169_wait_for_quiescence(struct net_device *dev)
 	rtl8169_irq_mask_and_ack(ioaddr);
 
 #ifdef CONFIG_R8169_NAPI
+	tp->intr_mask = 0xffff;
+	RTL_W16(IntrMask, tp->intr_event);
 	napi_enable(&tp->napi);
 #endif
 }