[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>
diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index ea117fc..a0d75b0 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1130,7 +1130,7 @@
 	u16 port = sky2->port;
 
 	netif_tx_lock_bh(dev);
-	netif_poll_disable(sky2->hw->dev[0]);
+	napi_disable(&hw->napi);
 
 	sky2->vlgrp = grp;
 	if (grp) {
@@ -1145,7 +1145,7 @@
 			     TX_VLAN_TAG_OFF);
 	}
 
-	netif_poll_enable(sky2->hw->dev[0]);
+	napi_enable(&hw->napi);
 	netif_tx_unlock_bh(dev);
 }
 #endif
@@ -1385,9 +1385,13 @@
 	sky2_prefetch_init(hw, txqaddr[port], sky2->tx_le_map,
 			   TX_RING_SIZE - 1);
 
+	napi_enable(&hw->napi);
+
 	err = sky2_rx_start(sky2);
-	if (err)
+	if (err) {
+		napi_disable(&hw->napi);
 		goto err_out;
+	}
 
 	/* Enable interrupts from phy/mac for port */
 	imask = sky2_read32(hw, B0_IMSK);
@@ -1676,6 +1680,8 @@
 	/* Stop more packets from being queued */
 	netif_stop_queue(dev);
 
+	napi_disable(&hw->napi);
+
 	/* Disable port IRQ */
 	imask = sky2_read32(hw, B0_IMSK);
 	imask &= ~portirq_msk[port];
@@ -2016,7 +2022,7 @@
 
 	dev->trans_start = jiffies;	/* prevent tx timeout */
 	netif_stop_queue(dev);
-	netif_poll_disable(hw->dev[0]);
+	napi_disable(&hw->napi);
 
 	synchronize_irq(hw->pdev->irq);
 
@@ -2043,12 +2049,16 @@
 	err = sky2_rx_start(sky2);
 	sky2_write32(hw, B0_IMSK, imask);
 
+	/* Unconditionally re-enable NAPI because even if we
+	 * call dev_close() that will do a napi_disable().
+	 */
+	napi_enable(&hw->napi);
+
 	if (err)
 		dev_close(dev);
 	else {
 		gma_write16(hw, port, GM_GP_CTRL, ctl);
 
-		netif_poll_enable(hw->dev[0]);
 		netif_wake_queue(dev);
 	}
 
@@ -2544,18 +2554,15 @@
 static void sky2_watchdog(unsigned long arg)
 {
 	struct sky2_hw *hw = (struct sky2_hw *) arg;
-	struct net_device *dev;
 
 	/* Check for lost IRQ once a second */
 	if (sky2_read32(hw, B0_ISRC)) {
-		dev = hw->dev[0];
-		if (__netif_rx_schedule_prep(dev))
-			__netif_rx_schedule(dev);
+		napi_schedule(&hw->napi);
 	} else {
 		int i, active = 0;
 
 		for (i = 0; i < hw->ports; i++) {
-			dev = hw->dev[i];
+			struct net_device *dev = hw->dev[i];
 			if (!netif_running(dev))
 				continue;
 			++active;
@@ -2605,11 +2612,11 @@
 		sky2_le_error(hw, 1, Q_XA2, TX_RING_SIZE);
 }
 
-static int sky2_poll(struct net_device *dev0, int *budget)
+static int sky2_poll(struct napi_struct *napi, int work_limit)
 {
-	struct sky2_hw *hw = ((struct sky2_port *) netdev_priv(dev0))->hw;
-	int work_done;
+	struct sky2_hw *hw = container_of(napi, struct sky2_hw, napi);
 	u32 status = sky2_read32(hw, B0_Y2_SP_EISR);
+	int work_done;
 
 	if (unlikely(status & Y2_IS_ERROR))
 		sky2_err_intr(hw, status);
@@ -2620,31 +2627,27 @@
 	if (status & Y2_IS_IRQ_PHY2)
 		sky2_phy_intr(hw, 1);
 
-	work_done = sky2_status_intr(hw, min(dev0->quota, *budget));
-	*budget -= work_done;
-	dev0->quota -= work_done;
+	work_done = sky2_status_intr(hw, work_limit);
 
 	/* More work? */
- 	if (hw->st_idx != sky2_read16(hw, STAT_PUT_IDX))
-		return 1;
+	if (hw->st_idx == sky2_read16(hw, STAT_PUT_IDX)) {
+		/* Bug/Errata workaround?
+		 * Need to kick the TX irq moderation timer.
+		 */
+		if (sky2_read8(hw, STAT_TX_TIMER_CTRL) == TIM_START) {
+			sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_STOP);
+			sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START);
+		}
 
-	/* Bug/Errata workaround?
-	 * Need to kick the TX irq moderation timer.
-	 */
-	if (sky2_read8(hw, STAT_TX_TIMER_CTRL) == TIM_START) {
-		sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_STOP);
-		sky2_write8(hw, STAT_TX_TIMER_CTRL, TIM_START);
+		napi_complete(napi);
+		sky2_read32(hw, B0_Y2_SP_LISR);
 	}
-	netif_rx_complete(dev0);
-
-	sky2_read32(hw, B0_Y2_SP_LISR);
-	return 0;
+	return work_done;
 }
 
 static irqreturn_t sky2_intr(int irq, void *dev_id)
 {
 	struct sky2_hw *hw = dev_id;
-	struct net_device *dev0 = hw->dev[0];
 	u32 status;
 
 	/* Reading this mask interrupts as side effect */
@@ -2653,8 +2656,8 @@
 		return IRQ_NONE;
 
 	prefetch(&hw->st_le[hw->st_idx]);
-	if (likely(__netif_rx_schedule_prep(dev0)))
-		__netif_rx_schedule(dev0);
+
+	napi_schedule(&hw->napi);
 
 	return IRQ_HANDLED;
 }
@@ -2663,10 +2666,8 @@
 static void sky2_netpoll(struct net_device *dev)
 {
 	struct sky2_port *sky2 = netdev_priv(dev);
-	struct net_device *dev0 = sky2->hw->dev[0];
 
-	if (netif_running(dev) && __netif_rx_schedule_prep(dev0))
-		__netif_rx_schedule(dev0);
+	napi_schedule(&sky2->hw->napi);
 }
 #endif
 
@@ -2914,8 +2915,6 @@
 	sky2_write32(hw, B0_IMSK, 0);
 	sky2_read32(hw, B0_IMSK);
 
-	netif_poll_disable(hw->dev[0]);
-
 	for (i = 0; i < hw->ports; i++) {
 		dev = hw->dev[i];
 		if (netif_running(dev))
@@ -2924,7 +2923,6 @@
 
 	sky2_reset(hw);
 	sky2_write32(hw, B0_IMSK, Y2_IS_BASE);
-	netif_poll_enable(hw->dev[0]);
 
 	for (i = 0; i < hw->ports; i++) {
 		dev = hw->dev[i];
@@ -3735,7 +3733,7 @@
 {
 	struct net_device *dev = seq->private;
 	const struct sky2_port *sky2 = netdev_priv(dev);
-	const struct sky2_hw *hw = sky2->hw;
+	struct sky2_hw *hw = sky2->hw;
 	unsigned port = sky2->port;
 	unsigned idx, last;
 	int sop;
@@ -3748,7 +3746,7 @@
 		   sky2_read32(hw, B0_IMSK),
 		   sky2_read32(hw, B0_Y2_SP_ICR));
 
-	netif_poll_disable(hw->dev[0]);
+	napi_disable(&hw->napi);
 	last = sky2_read16(hw, STAT_PUT_IDX);
 
 	if (hw->st_idx == last)
@@ -3818,7 +3816,7 @@
 		   last = sky2_read16(hw, Y2_QADDR(rxqaddr[port], PREF_UNIT_PUT_IDX)),
 		   sky2_read16(hw, Y2_QADDR(rxqaddr[port], PREF_UNIT_LAST_IDX)));
 
-	netif_poll_enable(hw->dev[0]);
+	napi_enable(&hw->napi);
 	return 0;
 }
 
@@ -3943,15 +3941,8 @@
 	SET_ETHTOOL_OPS(dev, &sky2_ethtool_ops);
 	dev->tx_timeout = sky2_tx_timeout;
 	dev->watchdog_timeo = TX_WATCHDOG;
-	if (port == 0)
-		dev->poll = sky2_poll;
-	dev->weight = NAPI_WEIGHT;
 #ifdef CONFIG_NET_POLL_CONTROLLER
-	/* Network console (only works on port 0)
-	 * because netpoll makes assumptions about NAPI
-	 */
-	if (port == 0)
-		dev->poll_controller = sky2_netpoll;
+	dev->poll_controller = sky2_netpoll;
 #endif
 
 	sky2 = netdev_priv(dev);
@@ -4166,6 +4157,7 @@
 		err = -ENOMEM;
 		goto err_out_free_pci;
 	}
+	netif_napi_add(dev, &hw->napi, sky2_poll, NAPI_WEIGHT);
 
 	if (!disable_msi && pci_enable_msi(pdev) == 0) {
 		err = sky2_test_msi(hw);
@@ -4288,8 +4280,6 @@
 	if (!hw)
 		return 0;
 
-	netif_poll_disable(hw->dev[0]);
-
 	for (i = 0; i < hw->ports; i++) {
 		struct net_device *dev = hw->dev[i];
 		struct sky2_port *sky2 = netdev_priv(dev);
@@ -4356,8 +4346,6 @@
 		}
 	}
 
-	netif_poll_enable(hw->dev[0]);
-
 	return 0;
 out:
 	dev_err(&pdev->dev, "resume failed (%d)\n", err);
@@ -4374,7 +4362,7 @@
 	if (!hw)
 		return;
 
-	netif_poll_disable(hw->dev[0]);
+	napi_disable(&hw->napi);
 
 	for (i = 0; i < hw->ports; i++) {
 		struct net_device *dev = hw->dev[i];