[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, 16 insertions, 20 deletions

diff --git a/drivers/net/pasemi_mac.c b/drivers/net/pasemi_mac.c
index 0b3066a6fe4..e63cc335a4b 100644
--- a/drivers/net/pasemi_mac.c
+++ b/drivers/net/pasemi_mac.c
@@ -584,7 +584,7 @@ static irqreturn_t pasemi_mac_rx_intr(int irq, void *data)
 	if (*mac->rx_status & PAS_STATUS_TIMER)
 		reg |= PAS_IOB_DMA_RXCH_RESET_TINTC;
 
-	netif_rx_schedule(dev);
+	netif_rx_schedule(dev, &mac->napi);
 
 	pci_write_config_dword(mac->iob_pdev,
 			       PAS_IOB_DMA_RXCH_RESET(mac->dma_rxch), reg);
@@ -808,7 +808,7 @@ static int pasemi_mac_open(struct net_device *dev)
 		dev_warn(&mac->pdev->dev, "phy init failed: %d\n", ret);
 
 	netif_start_queue(dev);
-	netif_poll_enable(dev);
+	napi_enable(&mac->napi);
 
 	/* Interrupts are a bit different for our DMA controller: While
 	 * it's got one a regular PCI device header, the interrupt there
@@ -845,7 +845,7 @@ static int pasemi_mac_open(struct net_device *dev)
 out_rx_int:
 	free_irq(mac->tx_irq, dev);
 out_tx_int:
-	netif_poll_disable(dev);
+	napi_disable(&mac->napi);
 	netif_stop_queue(dev);
 	pasemi_mac_free_tx_resources(dev);
 out_tx_resources:
@@ -869,6 +869,7 @@ static int pasemi_mac_close(struct net_device *dev)
 	}
 
 	netif_stop_queue(dev);
+	napi_disable(&mac->napi);
 
 	/* Clean out any pending buffers */
 	pasemi_mac_clean_tx(mac);
@@ -1047,26 +1048,20 @@ static void pasemi_mac_set_rx_mode(struct net_device *dev)
 }
 
 
-static int pasemi_mac_poll(struct net_device *dev, int *budget)
+static int pasemi_mac_poll(struct napi_struct *napi, int budget)
 {
-	int pkts, limit = min(*budget, dev->quota);
-	struct pasemi_mac *mac = netdev_priv(dev);
-
-	pkts = pasemi_mac_clean_rx(mac, limit);
+	struct pasemi_mac *mac = container_of(napi, struct pasemi_mac, napi);
+	struct net_device *dev = mac->netdev;
+	int pkts;
 
-	dev->quota -= pkts;
-	*budget -= pkts;
-
-	if (pkts < limit) {
+	pkts = pasemi_mac_clean_rx(mac, budget);
+	if (pkts < budget) {
 		/* all done, no more packets present */
-		netif_rx_complete(dev);
+		netif_rx_complete(dev, napi);
 
 		pasemi_mac_restart_rx_intr(mac);
-		return 0;
-	} else {
-		/* used up our quantum, so reschedule */
-		return 1;
 	}
+	return pkts;
 }
 
 static int __devinit
@@ -1099,6 +1094,10 @@ pasemi_mac_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	mac->netdev = dev;
 	mac->dma_pdev = pci_get_device(PCI_VENDOR_ID_PASEMI, 0xa007, NULL);
 
+	netif_napi_add(dev, &mac->napi, pasemi_mac_poll, 64);
+
+	dev->features = NETIF_F_HW_CSUM;
+
 	if (!mac->dma_pdev) {
 		dev_err(&pdev->dev, "Can't find DMA Controller\n");
 		err = -ENODEV;
@@ -1150,9 +1149,6 @@ pasemi_mac_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	dev->hard_start_xmit = pasemi_mac_start_tx;
 	dev->get_stats = pasemi_mac_get_stats;
 	dev->set_multicast_list = pasemi_mac_set_rx_mode;
-	dev->weight = 64;
-	dev->poll = pasemi_mac_poll;
-	dev->features = NETIF_F_HW_CSUM;
 
 	/* The dma status structure is located in the I/O bridge, and
 	 * is cache coherent.