ipv4: add mc_count to in_device.

This patch add mc_count to struct in_device and updates
increment/decrement/initilaize of this field in IPv4 and in IPv6.

- Also printing the vfs /proc entry (/proc/net/igmp) is adjusted to
use the new mc_count.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 6 insertions, 2 deletions

diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h
index c6f51ad52d5b..06fcdb45106b 100644
--- a/include/linux/inetdevice.h
+++ b/include/linux/inetdevice.h
@@ -25,6 +25,7 @@ struct in_device
         struct in_ifaddr        *ifa_list;      /* IP ifaddr chain              */
         rwlock_t                mc_list_lock;
         struct ip_mc_list       *mc_list;       /* IP multicast filter chain    */
+        int                     mc_count;                 /* Number of installed mcasts */
         spinlock_t              mc_tomb_lock;
         struct ip_mc_list       *mc_tomb;
         unsigned long           mr_v1_seen;
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index f70fac612596..7f9e337e3908 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1234,6 +1234,7 @@ void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
         write_lock_bh(&in_dev->mc_list_lock);
         im->next=in_dev->mc_list;
         in_dev->mc_list=im;
+        in_dev->mc_count++;
         write_unlock_bh(&in_dev->mc_list_lock);
 #ifdef CONFIG_IP_MULTICAST
         igmpv3_del_delrec(in_dev, im->multiaddr);
@@ -1282,6 +1283,7 @@ void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
                         if (--i->users == 0) {
                                 write_lock_bh(&in_dev->mc_list_lock);
                                 *ip = i->next;
+                                in_dev->mc_count--;
                                 write_unlock_bh(&in_dev->mc_list_lock);
                                 igmp_group_dropped(i);
 
@@ -1330,6 +1332,7 @@ void ip_mc_init_dev(struct in_device *in_dev)
         setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
                         (unsigned long)in_dev);
         in_dev->mr_ifc_count = 0;
+        in_dev->mc_count     = 0;
         setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
                         (unsigned long)in_dev);
         in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
@@ -1369,8 +1372,8 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
         write_lock_bh(&in_dev->mc_list_lock);
         while ((i = in_dev->mc_list) != NULL) {
                 in_dev->mc_list = i->next;
+                in_dev->mc_count--;
                 write_unlock_bh(&in_dev->mc_list_lock);
-
                 igmp_group_dropped(i);
                 ip_ma_put(i);
 
@@ -2383,7 +2386,7 @@ static int igmp_mc_seq_show(struct seq_file *seq, void *v)
 
                 if (state->in_dev->mc_list == im) {
                         seq_printf(seq, "%d\t%-10s: %5d %7s\n",
-                                   state->dev->ifindex, state->dev->name, state->dev->mc_count, querier);
+                                   state->dev->ifindex, state->dev->name, state->in_dev->mc_count, querier);
                 }
 
                 seq_printf(seq,