[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, 26 insertions, 16 deletions

diff --git a/drivers/net/via-rhine.c b/drivers/net/via-rhine.c
index b56dff26772d..7a5899059c44 100644
--- a/drivers/net/via-rhine.c
+++ b/drivers/net/via-rhine.c
@@ -389,6 +389,8 @@ struct rhine_private {
 
         struct pci_dev *pdev;
         long pioaddr;
+        struct net_device *dev;
+        struct napi_struct napi;
         struct net_device_stats stats;
         spinlock_t lock;
 
@@ -582,28 +584,25 @@ static void rhine_poll(struct net_device *dev)
 #endif
 
 #ifdef CONFIG_VIA_RHINE_NAPI
-static int rhine_napipoll(struct net_device *dev, int *budget)
+static int rhine_napipoll(struct napi_struct *napi, int budget)
 {
-        struct rhine_private *rp = netdev_priv(dev);
+        struct rhine_private *rp = container_of(napi, struct rhine_private, napi);
+        struct net_device *dev = rp->dev;
         void __iomem *ioaddr = rp->base;
-        int done, limit = min(dev->quota, *budget);
+        int work_done;
 
-        done = rhine_rx(dev, limit);
-        *budget -= done;
-        dev->quota -= done;
+        work_done = rhine_rx(dev, budget);
 
-        if (done < limit) {
-                netif_rx_complete(dev);
+        if (work_done < budget) {
+                netif_rx_complete(dev, napi);
 
                 iowrite16(IntrRxDone | IntrRxErr | IntrRxEmpty| IntrRxOverflow |
                           IntrRxDropped | IntrRxNoBuf | IntrTxAborted |
                           IntrTxDone | IntrTxError | IntrTxUnderrun |
                           IntrPCIErr | IntrStatsMax | IntrLinkChange,
                           ioaddr + IntrEnable);
-                return 0;
         }
-        else
-                return 1;
+        return work_done;
 }
 #endif
 
@@ -707,6 +706,7 @@ static int __devinit rhine_init_one(struct pci_dev *pdev,
         SET_NETDEV_DEV(dev, &pdev->dev);
 
         rp = netdev_priv(dev);
+        rp->dev = dev;
         rp->quirks = quirks;
         rp->pioaddr = pioaddr;
         rp->pdev = pdev;
@@ -785,8 +785,7 @@ static int __devinit rhine_init_one(struct pci_dev *pdev,
         dev->poll_controller = rhine_poll;
 #endif
 #ifdef CONFIG_VIA_RHINE_NAPI
-        dev->poll = rhine_napipoll;
-        dev->weight = 64;
+        netif_napi_add(dev, &rp->napi, rhine_napipoll, 64);
 #endif
         if (rp->quirks & rqRhineI)
                 dev->features |= NETIF_F_SG|NETIF_F_HW_CSUM;
@@ -1061,7 +1060,9 @@ static void init_registers(struct net_device *dev)
 
         rhine_set_rx_mode(dev);
 
-        netif_poll_enable(dev);
+#ifdef CONFIG_VIA_RHINE_NAPI
+        napi_enable(&rp->napi);
+#endif
 
         /* Enable interrupts by setting the interrupt mask. */
         iowrite16(IntrRxDone | IntrRxErr | IntrRxEmpty| IntrRxOverflow |
@@ -1196,6 +1197,10 @@ static void rhine_tx_timeout(struct net_device *dev)
         /* protect against concurrent rx interrupts */
         disable_irq(rp->pdev->irq);
 
+#ifdef CONFIG_VIA_RHINE_NAPI
+        napi_disable(&rp->napi);
+#endif
+
         spin_lock(&rp->lock);
 
         /* clear all descriptors */
@@ -1324,7 +1329,7 @@ static irqreturn_t rhine_interrupt(int irq, void *dev_instance)
                                   IntrPCIErr | IntrStatsMax | IntrLinkChange,
                                   ioaddr + IntrEnable);
 
-                        netif_rx_schedule(dev);
+                        netif_rx_schedule(dev, &rp->napi);
 #else
                         rhine_rx(dev, RX_RING_SIZE);
 #endif
@@ -1837,7 +1842,9 @@ static int rhine_close(struct net_device *dev)
         spin_lock_irq(&rp->lock);
 
         netif_stop_queue(dev);
-        netif_poll_disable(dev);
+#ifdef CONFIG_VIA_RHINE_NAPI
+        napi_disable(&rp->napi);
+#endif
 
         if (debug > 1)
                 printk(KERN_DEBUG "%s: Shutting down ethercard, "
@@ -1936,6 +1943,9 @@ static int rhine_suspend(struct pci_dev *pdev, pm_message_t state)
         if (!netif_running(dev))
                 return 0;
 
+#ifdef CONFIG_VIA_RHINE_NAPI
+        napi_disable(&rp->napi);
+#endif
         netif_device_detach(dev);
         pci_save_state(pdev);