[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>

1 files changed, 20 insertions, 24 deletions

diff --git a/drivers/net/skge.c b/drivers/net/skge.c
index e3d8520209b8..0bf46ed4e684 100644
--- a/drivers/net/skge.c
+++ b/drivers/net/skge.c
@@ -2528,7 +2528,7 @@ static int skge_up(struct net_device *dev)
 	skge_write32(hw, B0_IMSK, hw->intr_mask);
 	spin_unlock_irq(&hw->hw_lock);
 
-	netif_poll_enable(dev);
+	napi_enable(&skge->napi);
 	return 0;
 
  free_rx_ring:
@@ -2558,7 +2558,7 @@ static int skge_down(struct net_device *dev)
 	if (hw->chip_id == CHIP_ID_GENESIS && hw->phy_type == SK_PHY_XMAC)
 		del_timer_sync(&skge->link_timer);
 
-	netif_poll_disable(dev);
+	napi_disable(&skge->napi);
 	netif_carrier_off(dev);
 
 	spin_lock_irq(&hw->hw_lock);
@@ -3044,14 +3044,13 @@ static void skge_tx_done(struct net_device *dev)
 	}
 }
 
-static int skge_poll(struct net_device *dev, int *budget)
+static int skge_poll(struct napi_struct *napi, int to_do)
 {
-	struct skge_port *skge = netdev_priv(dev);
+	struct skge_port *skge = container_of(napi, struct skge_port, napi);
+	struct net_device *dev = skge->netdev;
 	struct skge_hw *hw = skge->hw;
 	struct skge_ring *ring = &skge->rx_ring;
 	struct skge_element *e;
-	unsigned long flags;
-	int to_do = min(dev->quota, *budget);
 	int work_done = 0;
 
 	skge_tx_done(dev);
@@ -3082,20 +3081,16 @@ static int skge_poll(struct net_device *dev, int *budget)
 	wmb();
 	skge_write8(hw, Q_ADDR(rxqaddr[skge->port], Q_CSR), CSR_START);
 
-	*budget -= work_done;
-	dev->quota -= work_done;
-
-	if (work_done >=  to_do)
-		return 1; /* not done */
-
-	spin_lock_irqsave(&hw->hw_lock, flags);
-	__netif_rx_complete(dev);
-	hw->intr_mask |= napimask[skge->port];
-  	skge_write32(hw, B0_IMSK, hw->intr_mask);
-	skge_read32(hw, B0_IMSK);
-	spin_unlock_irqrestore(&hw->hw_lock, flags);
+	if (work_done < to_do) {
+		spin_lock_irq(&hw->hw_lock);
+		__netif_rx_complete(dev, napi);
+		hw->intr_mask |= napimask[skge->port];
+		skge_write32(hw, B0_IMSK, hw->intr_mask);
+		skge_read32(hw, B0_IMSK);
+		spin_unlock_irq(&hw->hw_lock);
+	}
 
-	return 0;
+	return work_done;
 }
 
 /* Parity errors seem to happen when Genesis is connected to a switch
@@ -3252,8 +3247,9 @@ static irqreturn_t skge_intr(int irq, void *dev_id)
 	}
 
 	if (status & (IS_XA1_F|IS_R1_F)) {
+		struct skge_port *skge = netdev_priv(hw->dev[0]);
 		hw->intr_mask &= ~(IS_XA1_F|IS_R1_F);
-		netif_rx_schedule(hw->dev[0]);
+		netif_rx_schedule(hw->dev[0], &skge->napi);
 	}
 
 	if (status & IS_PA_TO_TX1)
@@ -3271,13 +3267,14 @@ static irqreturn_t skge_intr(int irq, void *dev_id)
 		skge_mac_intr(hw, 0);
 
 	if (hw->dev[1]) {
+		struct skge_port *skge = netdev_priv(hw->dev[1]);
+
 		if (status & (IS_XA2_F|IS_R2_F)) {
 			hw->intr_mask &= ~(IS_XA2_F|IS_R2_F);
-			netif_rx_schedule(hw->dev[1]);
+			netif_rx_schedule(hw->dev[1], &skge->napi);
 		}
 
 		if (status & IS_PA_TO_RX2) {
-			struct skge_port *skge = netdev_priv(hw->dev[1]);
 			++skge->net_stats.rx_over_errors;
 			skge_write16(hw, B3_PA_CTRL, PA_CLR_TO_RX2);
 		}
@@ -3569,8 +3566,6 @@ static struct net_device *skge_devinit(struct skge_hw *hw, int port,
 	SET_ETHTOOL_OPS(dev, &skge_ethtool_ops);
 	dev->tx_timeout = skge_tx_timeout;
 	dev->watchdog_timeo = TX_WATCHDOG;
-	dev->poll = skge_poll;
-	dev->weight = NAPI_WEIGHT;
 #ifdef CONFIG_NET_POLL_CONTROLLER
 	dev->poll_controller = skge_netpoll;
 #endif
@@ -3580,6 +3575,7 @@ static struct net_device *skge_devinit(struct skge_hw *hw, int port,
 		dev->features |= NETIF_F_HIGHDMA;
 
 	skge = netdev_priv(dev);
+	netif_napi_add(dev, &skge->napi, skge_poll, NAPI_WEIGHT);
 	skge->netdev = dev;
 	skge->hw = hw;
 	skge->msg_enable = netif_msg_init(debug, default_msg);