[GRE]: Make the fallback tunnel device per-net.

Everything is prepared for this change now. Create on in
init callback, use it over the code and destroy on net exit.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 32 insertions, 31 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 1a17c5beffdc..a8ec0904e5a6 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -126,10 +126,9 @@ static int ipgre_fb_tunnel_init(struct net_device *dev);
 
 static int ipgre_net_id;
 struct ipgre_net {
+        struct net_device *fb_tunnel_dev;
 };
 
-static struct net_device *ipgre_fb_tunnel_dev;
-
 /* Tunnel hash table */
 
 /*
@@ -168,6 +167,7 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net *net,
         unsigned h0 = HASH(remote);
         unsigned h1 = HASH(key);
         struct ip_tunnel *t;
+        struct ipgre_net *ign = net_generic(net, ipgre_net_id);
 
         for (t = tunnels_r_l[h0^h1]; t; t = t->next) {
                 if (local == t->parms.iph.saddr && remote == t->parms.iph.daddr) {
@@ -194,8 +194,8 @@ static struct ip_tunnel * ipgre_tunnel_lookup(struct net *net,
                         return t;
         }
 
-        if (ipgre_fb_tunnel_dev->flags&IFF_UP)
-                return netdev_priv(ipgre_fb_tunnel_dev);
+        if (ign->fb_tunnel_dev->flags&IFF_UP)
+                return netdev_priv(ign->fb_tunnel_dev);
         return NULL;
 }
 
@@ -977,7 +977,7 @@ ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
         switch (cmd) {
         case SIOCGETTUNNEL:
                 t = NULL;
-                if (dev == ipgre_fb_tunnel_dev) {
+                if (dev == ign->fb_tunnel_dev) {
                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p))) {
                                 err = -EFAULT;
                                 break;
@@ -1016,7 +1016,7 @@ ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
 
                 t = ipgre_tunnel_locate(net, &p, cmd == SIOCADDTUNNEL);
 
-                if (dev != ipgre_fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
+                if (dev != ign->fb_tunnel_dev && cmd == SIOCCHGTUNNEL) {
                         if (t != NULL) {
                                 if (t->dev != dev) {
                                         err = -EEXIST;
@@ -1071,7 +1071,7 @@ ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                 if (!capable(CAP_NET_ADMIN))
                         goto done;
 
-                if (dev == ipgre_fb_tunnel_dev) {
+                if (dev == ign->fb_tunnel_dev) {
                         err = -EFAULT;
                         if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof(p)))
                                 goto done;
@@ -1079,7 +1079,7 @@ ipgre_tunnel_ioctl (struct net_device *dev, struct ifreq *ifr, int cmd)
                         if ((t = ipgre_tunnel_locate(net, &p, 0)) == NULL)
                                 goto done;
                         err = -EPERM;
-                        if (t == netdev_priv(ipgre_fb_tunnel_dev))
+                        if (t == netdev_priv(ign->fb_tunnel_dev))
                                 goto done;
                         dev = t->dev;
                 }
@@ -1270,7 +1270,7 @@ static int ipgre_tunnel_init(struct net_device *dev)
         return 0;
 }
 
-static int __init ipgre_fb_tunnel_init(struct net_device *dev)
+static int ipgre_fb_tunnel_init(struct net_device *dev)
 {
         struct ip_tunnel *tunnel = netdev_priv(dev);
         struct iphdr *iph = &tunnel->parms.iph;
@@ -1308,8 +1308,25 @@ static int ipgre_init_net(struct net *net)
         if (err < 0)
                 goto err_assign;
 
+        ign->fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "gre0",
+                                           ipgre_tunnel_setup);
+        if (!ign->fb_tunnel_dev) {
+                err = -ENOMEM;
+                goto err_alloc_dev;
+        }
+
+        ign->fb_tunnel_dev->init = ipgre_fb_tunnel_init;
+        dev_net_set(ign->fb_tunnel_dev, net);
+
+        if ((err = register_netdev(ign->fb_tunnel_dev)))
+                goto err_reg_dev;
+
         return 0;
 
+err_reg_dev:
+        free_netdev(ign->fb_tunnel_dev);
+err_alloc_dev:
+        /* nothing */
 err_assign:
         kfree(ign);
 err_alloc:
@@ -1321,6 +1338,10 @@ static void ipgre_exit_net(struct net *net)
         struct ipgre_net *ign;
 
         ign = net_generic(net, ipgre_net_id);
+        rtnl_lock();
+        if (net != &init_net)
+                unregister_netdevice(ign->fb_tunnel_dev);
+        rtnl_unlock();
         kfree(ign);
 }
 
@@ -1344,31 +1365,11 @@ static int __init ipgre_init(void)
                 return -EAGAIN;
         }
 
-        ipgre_fb_tunnel_dev = alloc_netdev(sizeof(struct ip_tunnel), "gre0",
-                                           ipgre_tunnel_setup);
-        if (!ipgre_fb_tunnel_dev) {
-                err = -ENOMEM;
-                goto err1;
-        }
-
-        ipgre_fb_tunnel_dev->init = ipgre_fb_tunnel_init;
-
-        if ((err = register_netdev(ipgre_fb_tunnel_dev)))
-                goto err2;
-
         err = register_pernet_gen_device(&ipgre_net_id, &ipgre_net_ops);
         if (err < 0)
-                goto err3;
-out:
+                inet_del_protocol(&ipgre_protocol, IPPROTO_GRE);
+
         return err;
-err2:
-        free_netdev(ipgre_fb_tunnel_dev);
-err1:
-        inet_del_protocol(&ipgre_protocol, IPPROTO_GRE);
-        goto out;
-err3:
-        unregister_netdevice(ipgre_fb_tunnel_dev);
-        goto err1;
 }
 
 static void __exit ipgre_destroy_tunnels(void)