Merge tag 'renesas-cpufreq2-for-v3.17' of git://git.kernel.org/pub/scm/linux/kernel...

[cascardo/linux.git] / drivers / net / xen-netfront.c

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index 5a7872a..2ccb4a0 100644 (file)
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -1287,7 +1287,7 @@ static irqreturn_t xennet_rx_interrupt(int irq, void *dev_id)
 
        if (likely(netif_carrier_ok(dev) &&
                   RING_HAS_UNCONSUMED_RESPONSES(&queue->rx)))
-                       napi_schedule(&queue->napi);
+               napi_schedule(&queue->napi);
 
        return IRQ_HANDLED;
 }
@@ -1437,10 +1437,11 @@ static void xennet_end_access(int ref, void *page)
 static void xennet_disconnect_backend(struct netfront_info *info)
 {
        unsigned int i = 0;
-       struct netfront_queue *queue = NULL;
        unsigned int num_queues = info->netdev->real_num_tx_queues;
 
        for (i = 0; i < num_queues; ++i) {
+               struct netfront_queue *queue = &info->queues[i];
+
                /* Stop old i/f to prevent errors whilst we rebuild the state. */
                spin_lock_bh(&queue->rx_lock);
                spin_lock_irq(&queue->tx_lock);
@@ -1698,8 +1699,6 @@ static int xennet_init_queue(struct netfront_queue *queue)
                goto exit_free_tx;
        }
 
-       netif_napi_add(queue->info->netdev, &queue->napi, xennet_poll, 64);
-
        return 0;
 
  exit_free_tx:
@@ -1790,6 +1789,70 @@ error:
        return err;
 }
 
+static void xennet_destroy_queues(struct netfront_info *info)
+{
+       unsigned int i;
+
+       rtnl_lock();
+
+       for (i = 0; i < info->netdev->real_num_tx_queues; i++) {
+               struct netfront_queue *queue = &info->queues[i];
+
+               if (netif_running(info->netdev))
+                       napi_disable(&queue->napi);
+               netif_napi_del(&queue->napi);
+       }
+
+       rtnl_unlock();
+
+       kfree(info->queues);
+       info->queues = NULL;
+}
+
+static int xennet_create_queues(struct netfront_info *info,
+                               unsigned int num_queues)
+{
+       unsigned int i;
+       int ret;
+
+       info->queues = kcalloc(num_queues, sizeof(struct netfront_queue),
+                              GFP_KERNEL);
+       if (!info->queues)
+               return -ENOMEM;
+
+       rtnl_lock();
+
+       for (i = 0; i < num_queues; i++) {
+               struct netfront_queue *queue = &info->queues[i];
+
+               queue->id = i;
+               queue->info = info;
+
+               ret = xennet_init_queue(queue);
+               if (ret < 0) {
+                       dev_warn(&info->netdev->dev, "only created %d queues\n",
+                                num_queues);
+                       num_queues = i;
+                       break;
+               }
+
+               netif_napi_add(queue->info->netdev, &queue->napi,
+                              xennet_poll, 64);
+               if (netif_running(info->netdev))
+                       napi_enable(&queue->napi);
+       }
+
+       netif_set_real_num_tx_queues(info->netdev, num_queues);
+
+       rtnl_unlock();
+
+       if (num_queues == 0) {
+               dev_err(&info->netdev->dev, "no queues\n");
+               return -EINVAL;
+       }
+       return 0;
+}
+
 /* Common code used when first setting up, and when resuming. */
 static int talk_to_netback(struct xenbus_device *dev,
                           struct netfront_info *info)
@@ -1826,42 +1889,20 @@ static int talk_to_netback(struct xenbus_device *dev,
                goto out;
        }
 
-       /* Allocate array of queues */
-       info->queues = kcalloc(num_queues, sizeof(struct netfront_queue), GFP_KERNEL);
-       if (!info->queues) {
-               err = -ENOMEM;
-               goto out;
-       }
-       rtnl_lock();
-       netif_set_real_num_tx_queues(info->netdev, num_queues);
-       rtnl_unlock();
+       if (info->queues)
+               xennet_destroy_queues(info);
+
+       err = xennet_create_queues(info, num_queues);
+       if (err < 0)
+               goto destroy_ring;
 
        /* Create shared ring, alloc event channel -- for each queue */
        for (i = 0; i < num_queues; ++i) {
                queue = &info->queues[i];
-               queue->id = i;
-               queue->info = info;
-               err = xennet_init_queue(queue);
-               if (err) {
-                       /* xennet_init_queue() cleans up after itself on failure,
-                        * but we still have to clean up any previously initialised
-                        * queues. If i > 0, set num_queues to i, then goto
-                        * destroy_ring, which calls xennet_disconnect_backend()
-                        * to tidy up.
-                        */
-                       if (i > 0) {
-                               rtnl_lock();
-                               netif_set_real_num_tx_queues(info->netdev, i);
-                               rtnl_unlock();
-                               goto destroy_ring;
-                       } else {
-                               goto out;
-                       }
-               }
                err = setup_netfront(dev, queue, feature_split_evtchn);
                if (err) {
-                       /* As for xennet_init_queue(), setup_netfront() will tidy
-                        * up the current queue on error, but we need to clean up
+                       /* setup_netfront() will tidy up the current
+                        * queue on error, but we need to clean up
                         * those already allocated.
                         */
                        if (i > 0) {