[NET]: Make NAPI polling independent of struct net_device objects.

Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 21 insertions, 20 deletions

diff --git a/drivers/net/chelsio/common.h b/drivers/net/chelsio/common.h
index 8ba702c8b560..b5de4452cf24 100644
--- a/drivers/net/chelsio/common.h
+++ b/drivers/net/chelsio/common.h
@@ -278,6 +278,7 @@ struct adapter {
 	struct peespi *espi;
 	struct petp   *tp;
 
+	struct napi_struct napi;
 	struct port_info port[MAX_NPORTS];
 	struct delayed_work stats_update_task;
 	struct timer_list stats_update_timer;
diff --git a/drivers/net/chelsio/cxgb2.c b/drivers/net/chelsio/cxgb2.c
index 231ce43b97cf..593736c7550d 100644
--- a/drivers/net/chelsio/cxgb2.c
+++ b/drivers/net/chelsio/cxgb2.c
@@ -255,8 +255,11 @@ static int cxgb_open(struct net_device *dev)
 	struct adapter *adapter = dev->priv;
 	int other_ports = adapter->open_device_map & PORT_MASK;
 
-	if (!adapter->open_device_map && (err = cxgb_up(adapter)) < 0)
+	napi_enable(&adapter->napi);
+	if (!adapter->open_device_map && (err = cxgb_up(adapter)) < 0) {
+		napi_disable(&adapter->napi);
 		return err;
+	}
 
 	__set_bit(dev->if_port, &adapter->open_device_map);
 	link_start(&adapter->port[dev->if_port]);
@@ -274,6 +277,7 @@ static int cxgb_close(struct net_device *dev)
 	struct cmac *mac = p->mac;
 
 	netif_stop_queue(dev);
+	napi_disable(&adapter->napi);
 	mac->ops->disable(mac, MAC_DIRECTION_TX | MAC_DIRECTION_RX);
 	netif_carrier_off(dev);
 
@@ -1113,8 +1117,7 @@ static int __devinit init_one(struct pci_dev *pdev,
 		netdev->poll_controller = t1_netpoll;
 #endif
 #ifdef CONFIG_CHELSIO_T1_NAPI
-		netdev->weight = 64;
-		netdev->poll = t1_poll;
+		netif_napi_add(netdev, &adapter->napi, t1_poll, 64);
 #endif
 
 		SET_ETHTOOL_OPS(netdev, &t1_ethtool_ops);
diff --git a/drivers/net/chelsio/sge.c b/drivers/net/chelsio/sge.c
index e4f874a70fe5..ffa7e649a6ef 100644
--- a/drivers/net/chelsio/sge.c
+++ b/drivers/net/chelsio/sge.c
@@ -1620,23 +1620,20 @@ static int process_pure_responses(struct adapter *adapter)
  * or protection from interrupts as data interrupts are off at this point and
  * other adapter interrupts do not interfere.
  */
-int t1_poll(struct net_device *dev, int *budget)
+int t1_poll(struct napi_struct *napi, int budget)
 {
-	struct adapter *adapter = dev->priv;
+	struct adapter *adapter = container_of(napi, struct adapter, napi);
+	struct net_device *dev = adapter->port[0].dev;
 	int work_done;
 
-	work_done = process_responses(adapter, min(*budget, dev->quota));
-	*budget -= work_done;
-	dev->quota -= work_done;
-
-	if (unlikely(responses_pending(adapter)))
-		return 1;
-
-	netif_rx_complete(dev);
-	writel(adapter->sge->respQ.cidx, adapter->regs + A_SG_SLEEPING);
-
-	return 0;
+	work_done = process_responses(adapter, budget);
 
+	if (likely(!responses_pending(adapter))) {
+		netif_rx_complete(dev, napi);
+		writel(adapter->sge->respQ.cidx,
+		       adapter->regs + A_SG_SLEEPING);
+	}
+	return work_done;
 }
 
 /*
@@ -1653,13 +1650,13 @@ irqreturn_t t1_interrupt(int irq, void *data)
 
 		writel(F_PL_INTR_SGE_DATA, adapter->regs + A_PL_CAUSE);
 
-		if (__netif_rx_schedule_prep(dev)) {
+		if (napi_schedule_prep(&adapter->napi)) {
 			if (process_pure_responses(adapter))
-				__netif_rx_schedule(dev);
+				__netif_rx_schedule(dev, &adapter->napi);
 			else {
 				/* no data, no NAPI needed */
 				writel(sge->respQ.cidx, adapter->regs + A_SG_SLEEPING);
-				netif_poll_enable(dev);	/* undo schedule_prep */
+				napi_enable(&adapter->napi);	/* undo schedule_prep */
 			}
 		}
 		return IRQ_HANDLED;
diff --git a/drivers/net/chelsio/sge.h b/drivers/net/chelsio/sge.h
index d132a0ef2a22..713d9c55f24d 100644
--- a/drivers/net/chelsio/sge.h
+++ b/drivers/net/chelsio/sge.h
@@ -77,7 +77,7 @@ int t1_sge_configure(struct sge *, struct sge_params *);
 int t1_sge_set_coalesce_params(struct sge *, struct sge_params *);
 void t1_sge_destroy(struct sge *);
 irqreturn_t t1_interrupt(int irq, void *cookie);
-int t1_poll(struct net_device *, int *);
+int t1_poll(struct napi_struct *, int);
 
 int t1_start_xmit(struct sk_buff *skb, struct net_device *dev);
 void t1_set_vlan_accel(struct adapter *adapter, int on_off);