firewire: net: set carrier state at ifup

At ifup, carrier status would be shown on even if it actually was off.
Also add an include for ethtool_ops rather than to rely on the one from
netdevice.h.

Note, we can alas not use fwnet_device_mutex to serialize access to
dev->peer_count (as I originally wanted).  This would cause a lock
inversion:
  - fwnet_probe | takes fwnet_device_mutex
      + register_netdev | takes rtnl_mutex
  - devinet_ioctl | takes rtnl_mutex
      + fwnet_open | ...must not take fwnet_device_mutex

Hence use the dev->lock spinlock for serialization.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

1 files changed, 21 insertions, 15 deletions

diff --git a/drivers/firewire/net.c b/drivers/firewire/net.c
index 7fd51c9e243d..c2e194c58667 100644
--- a/drivers/firewire/net.c
+++ b/drivers/firewire/net.c
@@ -9,6 +9,7 @@
 #include <linux/bug.h>
 #include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/ethtool.h>
 #include <linux/firewire.h>
 #include <linux/firewire-constants.h>
 #include <linux/highmem.h>
@@ -178,8 +179,8 @@ struct fwnet_device {
 
         /* Number of tx datagrams that have been queued but not yet acked */
         int queued_datagrams;
-        int peer_count;
 
+        int peer_count;
         struct list_head peer_list;
         struct fw_card *card;
         struct net_device *netdev;
@@ -1222,6 +1223,14 @@ static int fwnet_broadcast_start(struct fwnet_device *dev)
         return retval;
 }
 
+static void set_carrier_state(struct fwnet_device *dev)
+{
+        if (dev->peer_count > 1)
+                netif_carrier_on(dev->netdev);
+        else
+                netif_carrier_off(dev->netdev);
+}
+
 /* ifup */
 static int fwnet_open(struct net_device *net)
 {
@@ -1235,6 +1244,10 @@ static int fwnet_open(struct net_device *net)
         }
         netif_start_queue(net);
 
+        spin_lock_irq(&dev->lock);
+        set_carrier_state(dev);
+        spin_unlock_irq(&dev->lock);
+
         return 0;
 }
 
@@ -1429,7 +1442,6 @@ static void fwnet_init_dev(struct net_device *net)
         net->type               = ARPHRD_IEEE1394;
         net->tx_queue_len       = FWNET_TX_QUEUE_LEN;
         net->ethtool_ops        = &fwnet_ethtool_ops;
-
 }
 
 /* caller must hold fwnet_device_mutex */
@@ -1471,6 +1483,7 @@ static int fwnet_add_peer(struct fwnet_device *dev,
         spin_lock_irq(&dev->lock);
         list_add_tail(&peer->peer_link, &dev->peer_list);
         dev->peer_count++;
+        set_carrier_state(dev);
         spin_unlock_irq(&dev->lock);
 
         return 0;
@@ -1542,9 +1555,6 @@ static int fwnet_probe(struct device *_dev)
                 unregister_netdev(net);
                 list_del(&dev->dev_link);
         }
-
-        if (dev->peer_count > 1)
-                netif_carrier_on(net);
  out:
         if (ret && allocated_netdev)
                 free_netdev(net);
@@ -1554,14 +1564,15 @@ static int fwnet_probe(struct device *_dev)
         return ret;
 }
 
-static void fwnet_remove_peer(struct fwnet_peer *peer)
+static void fwnet_remove_peer(struct fwnet_peer *peer, struct fwnet_device *dev)
 {
         struct fwnet_partial_datagram *pd, *pd_next;
 
-        spin_lock_irq(&peer->dev->lock);
+        spin_lock_irq(&dev->lock);
         list_del(&peer->peer_link);
-        peer->dev->peer_count--;
-        spin_unlock_irq(&peer->dev->lock);
+        dev->peer_count--;
+        set_carrier_state(dev);
+        spin_unlock_irq(&dev->lock);
 
         list_for_each_entry_safe(pd, pd_next, &peer->pd_list, pd_link)
                 fwnet_pd_delete(pd);
@@ -1578,12 +1589,7 @@ static int fwnet_remove(struct device *_dev)
 
         mutex_lock(&fwnet_device_mutex);
 
-        fwnet_remove_peer(peer);
-
-        /* If we serve just one node, that means we lost link
-                with outer world */
-        if (dev->peer_count == 1)
-                netif_carrier_off(dev->netdev);
+        fwnet_remove_peer(peer, dev);
 
         if (list_empty(&dev->peer_list)) {
                 net = dev->netdev;