[NET]: Fix neighbour destructor handling.

->neigh_destructor() is killed (not used), replaced with
->neigh_cleanup(), which is called when neighbor entry goes to dead
state. At this point everything is still valid: neigh->dev,
neigh->parms etc.

The device should guarantee that dead neighbor entries (neigh->dead !=
0) do not get private part initialized, otherwise nobody will cleanup
it.

I think this is enough for ipoib which is the only user of this thing.
Initialization private part of neighbor entries happens in ipib
start_xmit routine, which is not reached when device is down.  But it
would be better to add explicit test for neigh->dead in any case.

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 10 insertions, 13 deletions

diff --git a/net/atm/clip.c b/net/atm/clip.c
index ebb5d0ce8b6f..8c3825816085 100644
--- a/net/atm/clip.c
+++ b/net/atm/clip.c
@@ -261,14 +261,6 @@ static void clip_pop(struct atm_vcc *vcc, struct sk_buff *skb)
         spin_unlock_irqrestore(&PRIV(dev)->xoff_lock, flags);
 }
 
-static void clip_neigh_destroy(struct neighbour *neigh)
-{
-        DPRINTK("clip_neigh_destroy (neigh %p)\n", neigh);
-        if (NEIGH2ENTRY(neigh)->vccs)
-                printk(KERN_CRIT "clip_neigh_destroy: vccs != NULL !!!\n");
-        NEIGH2ENTRY(neigh)->vccs = (void *) NEIGHBOR_DEAD;
-}
-
 static void clip_neigh_solicit(struct neighbour *neigh, struct sk_buff *skb)
 {
         DPRINTK("clip_neigh_solicit (neigh %p, skb %p)\n", neigh, skb);
@@ -342,7 +334,6 @@ static struct neigh_table clip_tbl = {
         /* parameters are copied from ARP ... */
         .parms = {
                 .tbl                    = &clip_tbl,
-                .neigh_destructor       = clip_neigh_destroy,
                 .base_reachable_time    = 30 * HZ,
                 .retrans_time           = 1 * HZ,
                 .gc_staletime           = 60 * HZ,
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index 3183142c6044..cfc60019cf92 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -140,6 +140,8 @@ static int neigh_forced_gc(struct neigh_table *tbl)
                                 n->dead = 1;
                                 shrunk  = 1;
                                 write_unlock(&n->lock);
+                                if (n->parms->neigh_cleanup)
+                                        n->parms->neigh_cleanup(n);
                                 neigh_release(n);
                                 continue;
                         }
@@ -211,6 +213,8 @@ static void neigh_flush_dev(struct neigh_table *tbl, struct net_device *dev)
                                 NEIGH_PRINTK2("neigh %p is stray.\n", n);
                         }
                         write_unlock(&n->lock);
+                        if (n->parms->neigh_cleanup)
+                                n->parms->neigh_cleanup(n);
                         neigh_release(n);
                 }
         }
@@ -582,9 +586,6 @@ void neigh_destroy(struct neighbour *neigh)
                         kfree(hh);
         }
 
-        if (neigh->parms->neigh_destructor)
-                (neigh->parms->neigh_destructor)(neigh);
-
         skb_queue_purge(&neigh->arp_queue);
 
         dev_put(neigh->dev);
@@ -675,6 +676,8 @@ static void neigh_periodic_timer(unsigned long arg)
                         *np = n->next;
                         n->dead = 1;
                         write_unlock(&n->lock);
+                        if (n->parms->neigh_cleanup)
+                                n->parms->neigh_cleanup(n);
                         neigh_release(n);
                         continue;
                 }
@@ -2088,8 +2091,11 @@ void __neigh_for_each_release(struct neigh_table *tbl,
                         } else
                                 np = &n->next;
                         write_unlock(&n->lock);
-                        if (release)
+                        if (release) {
+                                if (n->parms->neigh_cleanup)
+                                        n->parms->neigh_cleanup(n);
                                 neigh_release(n);
+                        }
                 }
         }
 }