net: dynamically allocate fqdir structures

Following patch will add rcu grace period before fqdir
rhashtable destruction, so we need to dynamically allocate
fqdir structures to not force expensive synchronize_rcu() calls
in netns dismantle path.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 13 insertions, 11 deletions

diff --git a/net/ieee802154/6lowpan/reassembly.c b/net/ieee802154/6lowpan/reassembly.c
index 03a444c9e191..e59c3b708969 100644
--- a/net/ieee802154/6lowpan/reassembly.c
+++ b/net/ieee802154/6lowpan/reassembly.c
@@ -79,7 +79,7 @@ fq_find(struct net *net, const struct lowpan_802154_cb *cb,
         key.src = *src;
         key.dst = *dst;
 
-        q = inet_frag_find(&ieee802154_lowpan->fqdir, &key);
+        q = inet_frag_find(ieee802154_lowpan->fqdir, &key);
         if (!q)
                 return NULL;
 
@@ -377,11 +377,11 @@ static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
                         table[0].procname = NULL;
         }
 
-        table[0].data   = &ieee802154_lowpan->fqdir.high_thresh;
-        table[0].extra1 = &ieee802154_lowpan->fqdir.low_thresh;
-        table[1].data   = &ieee802154_lowpan->fqdir.low_thresh;
-        table[1].extra2 = &ieee802154_lowpan->fqdir.high_thresh;
-        table[2].data   = &ieee802154_lowpan->fqdir.timeout;
+        table[0].data   = &ieee802154_lowpan->fqdir->high_thresh;
+        table[0].extra1 = &ieee802154_lowpan->fqdir->low_thresh;
+        table[1].data   = &ieee802154_lowpan->fqdir->low_thresh;
+        table[1].extra2 = &ieee802154_lowpan->fqdir->high_thresh;
+        table[2].data   = &ieee802154_lowpan->fqdir->timeout;
 
         hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table);
         if (hdr == NULL)
@@ -449,16 +449,18 @@ static int __net_init lowpan_frags_init_net(struct net *net)
                 net_ieee802154_lowpan(net);
         int res;
 
-        ieee802154_lowpan->fqdir.high_thresh = IPV6_FRAG_HIGH_THRESH;
-        ieee802154_lowpan->fqdir.low_thresh = IPV6_FRAG_LOW_THRESH;
-        ieee802154_lowpan->fqdir.timeout = IPV6_FRAG_TIMEOUT;
 
         res = fqdir_init(&ieee802154_lowpan->fqdir, &lowpan_frags, net);
         if (res < 0)
                 return res;
+
+        ieee802154_lowpan->fqdir->high_thresh = IPV6_FRAG_HIGH_THRESH;
+        ieee802154_lowpan->fqdir->low_thresh = IPV6_FRAG_LOW_THRESH;
+        ieee802154_lowpan->fqdir->timeout = IPV6_FRAG_TIMEOUT;
+
         res = lowpan_frags_ns_sysctl_register(net);
         if (res < 0)
-                fqdir_exit(&ieee802154_lowpan->fqdir);
+                fqdir_exit(ieee802154_lowpan->fqdir);
         return res;
 }
 
@@ -468,7 +470,7 @@ static void __net_exit lowpan_frags_exit_net(struct net *net)
                 net_ieee802154_lowpan(net);
 
         lowpan_frags_ns_sysctl_unregister(net);
-        fqdir_exit(&ieee802154_lowpan->fqdir);
+        fqdir_exit(ieee802154_lowpan->fqdir);
 }
 
 static struct pernet_operations lowpan_frags_ops = {