netns: ip6mr: dynamically allocates vif6_table

Preliminary work to make IPv6 multicast forwarding netns-aware.

Dynamically allocates interface table vif6_table and moves it to 
struct netns_ipv6, and updates MIF_EXISTS() macro. 

At the moment, vif6_table is only referenced in init_net.

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 68 insertions, 39 deletions

diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
index 02163dbf84c3..bae3ef649664 100644
--- a/net/ipv6/ip6mr.c
+++ b/net/ipv6/ip6mr.c
@@ -59,10 +59,7 @@ static DEFINE_RWLOCK(mrt_lock);
  *      Multicast router control variables
  */
 
-static struct mif_device vif6_table[MAXMIFS];           /* Devices              */
-static int maxvif;
-
-#define MIF_EXISTS(idx) (vif6_table[idx].dev != NULL)
+#define MIF_EXISTS(_net, _idx) ((_net)->ipv6.vif6_table[_idx].dev != NULL)
 
 static int mroute_do_assert;                            /* Set in PIM assert    */
 #ifdef CONFIG_IPV6_PIMSM_V2
@@ -145,11 +142,11 @@ struct ipmr_vif_iter {
 static struct mif_device *ip6mr_vif_seq_idx(struct ipmr_vif_iter *iter,
                                             loff_t pos)
 {
-        for (iter->ct = 0; iter->ct < maxvif; ++iter->ct) {
-                if (!MIF_EXISTS(iter->ct))
+        for (iter->ct = 0; iter->ct < init_net.ipv6.maxvif; ++iter->ct) {
+                if (!MIF_EXISTS(&init_net, iter->ct))
                         continue;
                 if (pos-- == 0)
-                        return &vif6_table[iter->ct];
+                        return &init_net.ipv6.vif6_table[iter->ct];
         }
         return NULL;
 }
@@ -170,10 +167,10 @@ static void *ip6mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos)
         if (v == SEQ_START_TOKEN)
                 return ip6mr_vif_seq_idx(iter, 0);
 
-        while (++iter->ct < maxvif) {
-                if (!MIF_EXISTS(iter->ct))
+        while (++iter->ct < init_net.ipv6.maxvif) {
+                if (!MIF_EXISTS(&init_net, iter->ct))
                         continue;
-                return &vif6_table[iter->ct];
+                return &init_net.ipv6.vif6_table[iter->ct];
         }
         return NULL;
 }
@@ -195,7 +192,7 @@ static int ip6mr_vif_seq_show(struct seq_file *seq, void *v)
 
                 seq_printf(seq,
                            "%2td %-10s %8ld %7ld  %8ld %7ld %05X\n",
-                           vif - vif6_table,
+                           vif - init_net.ipv6.vif6_table,
                            name, vif->bytes_in, vif->pkt_in,
                            vif->bytes_out, vif->pkt_out,
                            vif->flags);
@@ -305,7 +302,7 @@ static int ipmr_mfc_seq_show(struct seq_file *seq, void *v)
                                    mfc->mfc_un.res.wrong_if);
                         for (n = mfc->mfc_un.res.minvif;
                              n < mfc->mfc_un.res.maxvif; n++) {
-                                if (MIF_EXISTS(n) &&
+                                if (MIF_EXISTS(&init_net, n) &&
                                     mfc->mfc_un.res.ttls[n] < 255)
                                         seq_printf(seq,
                                                    " %2d:%-3d",
@@ -374,7 +371,7 @@ static int pim6_rcv(struct sk_buff *skb)
 
         read_lock(&mrt_lock);
         if (reg_vif_num >= 0)
-                reg_dev = vif6_table[reg_vif_num].dev;
+                reg_dev = init_net.ipv6.vif6_table[reg_vif_num].dev;
         if (reg_dev)
                 dev_hold(reg_dev);
         read_unlock(&mrt_lock);
@@ -470,10 +467,10 @@ static int mif6_delete(int vifi)
 {
         struct mif_device *v;
         struct net_device *dev;
-        if (vifi < 0 || vifi >= maxvif)
+        if (vifi < 0 || vifi >= init_net.ipv6.maxvif)
                 return -EADDRNOTAVAIL;
 
-        v = &vif6_table[vifi];
+        v = &init_net.ipv6.vif6_table[vifi];
 
         write_lock_bh(&mrt_lock);
         dev = v->dev;
@@ -489,13 +486,13 @@ static int mif6_delete(int vifi)
                 reg_vif_num = -1;
 #endif
 
-        if (vifi + 1 == maxvif) {
+        if (vifi + 1 == init_net.ipv6.maxvif) {
                 int tmp;
                 for (tmp = vifi - 1; tmp >= 0; tmp--) {
-                        if (MIF_EXISTS(tmp))
+                        if (MIF_EXISTS(&init_net, tmp))
                                 break;
                 }
-                maxvif = tmp + 1;
+                init_net.ipv6.maxvif = tmp + 1;
         }
 
         write_unlock_bh(&mrt_lock);
@@ -586,8 +583,9 @@ static void ip6mr_update_thresholds(struct mfc6_cache *cache, unsigned char *ttl
         cache->mfc_un.res.maxvif = 0;
         memset(cache->mfc_un.res.ttls, 255, MAXMIFS);
 
-        for (vifi = 0; vifi < maxvif; vifi++) {
-                if (MIF_EXISTS(vifi) && ttls[vifi] && ttls[vifi] < 255) {
+        for (vifi = 0; vifi < init_net.ipv6.maxvif; vifi++) {
+                if (MIF_EXISTS(&init_net, vifi) &&
+                    ttls[vifi] && ttls[vifi] < 255) {
                         cache->mfc_un.res.ttls[vifi] = ttls[vifi];
                         if (cache->mfc_un.res.minvif > vifi)
                                 cache->mfc_un.res.minvif = vifi;
@@ -600,12 +598,12 @@ static void ip6mr_update_thresholds(struct mfc6_cache *cache, unsigned char *ttl
 static int mif6_add(struct mif6ctl *vifc, int mrtsock)
 {
         int vifi = vifc->mif6c_mifi;
-        struct mif_device *v = &vif6_table[vifi];
+        struct mif_device *v = &init_net.ipv6.vif6_table[vifi];
         struct net_device *dev;
         int err;
 
         /* Is vif busy ? */
-        if (MIF_EXISTS(vifi))
+        if (MIF_EXISTS(&init_net, vifi))
                 return -EADDRINUSE;
 
         switch (vifc->mif6c_flags) {
@@ -665,8 +663,8 @@ static int mif6_add(struct mif6ctl *vifc, int mrtsock)
         if (v->flags & MIFF_REGISTER)
                 reg_vif_num = vifi;
 #endif
-        if (vifi + 1 > maxvif)
-                maxvif = vifi + 1;
+        if (vifi + 1 > init_net.ipv6.maxvif)
+                init_net.ipv6.maxvif = vifi + 1;
         write_unlock_bh(&mrt_lock);
         return 0;
 }
@@ -946,8 +944,8 @@ static int ip6mr_device_event(struct notifier_block *this,
         if (event != NETDEV_UNREGISTER)
                 return NOTIFY_DONE;
 
-        v = &vif6_table[0];
-        for (ct = 0; ct < maxvif; ct++, v++) {
+        v = &init_net.ipv6.vif6_table[0];
+        for (ct = 0; ct < init_net.ipv6.maxvif; ct++, v++) {
                 if (v->dev == dev)
                         mif6_delete(ct);
         }
@@ -962,6 +960,30 @@ static struct notifier_block ip6_mr_notifier = {
  *      Setup for IP multicast routing
  */
 
+static int __net_init ip6mr_net_init(struct net *net)
+{
+        int err = 0;
+
+        net->ipv6.vif6_table = kcalloc(MAXMIFS, sizeof(struct mif_device),
+                                       GFP_KERNEL);
+        if (!net->ipv6.vif6_table) {
+                err = -ENOMEM;
+                goto fail;
+        }
+fail:
+        return err;
+}
+
+static void __net_exit ip6mr_net_exit(struct net *net)
+{
+        kfree(net->ipv6.vif6_table);
+}
+
+static struct pernet_operations ip6mr_net_ops = {
+        .init = ip6mr_net_init,
+        .exit = ip6mr_net_exit,
+};
+
 int __init ip6_mr_init(void)
 {
         int err;
@@ -973,6 +995,10 @@ int __init ip6_mr_init(void)
         if (!mrt_cachep)
                 return -ENOMEM;
 
+        err = register_pernet_subsys(&ip6mr_net_ops);
+        if (err)
+                goto reg_pernet_fail;
+
         setup_timer(&ipmr_expire_timer, ipmr_expire_process, 0);
         err = register_netdevice_notifier(&ip6_mr_notifier);
         if (err)
@@ -994,6 +1020,8 @@ proc_vif_fail:
 #endif
 reg_notif_fail:
         del_timer(&ipmr_expire_timer);
+        unregister_pernet_subsys(&ip6mr_net_ops);
+reg_pernet_fail:
         kmem_cache_destroy(mrt_cachep);
         return err;
 }
@@ -1006,6 +1034,7 @@ void ip6_mr_cleanup(void)
 #endif
         unregister_netdevice_notifier(&ip6_mr_notifier);
         del_timer(&ipmr_expire_timer);
+        unregister_pernet_subsys(&ip6mr_net_ops);
         kmem_cache_destroy(mrt_cachep);
 }
 
@@ -1095,8 +1124,8 @@ static void mroute_clean_tables(struct sock *sk)
         /*
          *      Shut down all active vif entries
          */
-        for (i = 0; i < maxvif; i++) {
-                if (!(vif6_table[i].flags & VIFF_STATIC))
+        for (i = 0; i < init_net.ipv6.maxvif; i++) {
+                if (!(init_net.ipv6.vif6_table[i].flags & VIFF_STATIC))
                         mif6_delete(i);
         }
 
@@ -1346,11 +1375,11 @@ int ip6mr_ioctl(struct sock *sk, int cmd, void __user *arg)
         case SIOCGETMIFCNT_IN6:
                 if (copy_from_user(&vr, arg, sizeof(vr)))
                         return -EFAULT;
-                if (vr.mifi >= maxvif)
+                if (vr.mifi >= init_net.ipv6.maxvif)
                         return -EINVAL;
                 read_lock(&mrt_lock);
-                vif = &vif6_table[vr.mifi];
-                if (MIF_EXISTS(vr.mifi)) {
+                vif = &init_net.ipv6.vif6_table[vr.mifi];
+                if (MIF_EXISTS(&init_net, vr.mifi)) {
                         vr.icount = vif->pkt_in;
                         vr.ocount = vif->pkt_out;
                         vr.ibytes = vif->bytes_in;
@@ -1401,7 +1430,7 @@ static inline int ip6mr_forward2_finish(struct sk_buff *skb)
 static int ip6mr_forward2(struct sk_buff *skb, struct mfc6_cache *c, int vifi)
 {
         struct ipv6hdr *ipv6h;
-        struct mif_device *vif = &vif6_table[vifi];
+        struct mif_device *vif = &init_net.ipv6.vif6_table[vifi];
         struct net_device *dev;
         struct dst_entry *dst;
         struct flowi fl;
@@ -1474,8 +1503,8 @@ out_free:
 static int ip6mr_find_vif(struct net_device *dev)
 {
         int ct;
-        for (ct = maxvif - 1; ct >= 0; ct--) {
-                if (vif6_table[ct].dev == dev)
+        for (ct = init_net.ipv6.maxvif - 1; ct >= 0; ct--) {
+                if (init_net.ipv6.vif6_table[ct].dev == dev)
                         break;
         }
         return ct;
@@ -1493,7 +1522,7 @@ static int ip6_mr_forward(struct sk_buff *skb, struct mfc6_cache *cache)
         /*
          * Wrong interface: drop packet and (maybe) send PIM assert.
          */
-        if (vif6_table[vif].dev != skb->dev) {
+        if (init_net.ipv6.vif6_table[vif].dev != skb->dev) {
                 int true_vifi;
 
                 cache->mfc_un.res.wrong_if++;
@@ -1514,8 +1543,8 @@ static int ip6_mr_forward(struct sk_buff *skb, struct mfc6_cache *cache)
                 goto dont_forward;
         }
 
-        vif6_table[vif].pkt_in++;
-        vif6_table[vif].bytes_in += skb->len;
+        init_net.ipv6.vif6_table[vif].pkt_in++;
+        init_net.ipv6.vif6_table[vif].bytes_in += skb->len;
 
         /*
          *      Forward the frame
@@ -1583,7 +1612,7 @@ ip6mr_fill_mroute(struct sk_buff *skb, struct mfc6_cache *c, struct rtmsg *rtm)
 {
         int ct;
         struct rtnexthop *nhp;
-        struct net_device *dev = vif6_table[c->mf6c_parent].dev;
+        struct net_device *dev = init_net.ipv6.vif6_table[c->mf6c_parent].dev;
         u8 *b = skb_tail_pointer(skb);
         struct rtattr *mp_head;
 
@@ -1599,7 +1628,7 @@ ip6mr_fill_mroute(struct sk_buff *skb, struct mfc6_cache *c, struct rtmsg *rtm)
                         nhp = (struct rtnexthop *)skb_put(skb, RTA_ALIGN(sizeof(*nhp)));
                         nhp->rtnh_flags = 0;
                         nhp->rtnh_hops = c->mfc_un.res.ttls[ct];
-                        nhp->rtnh_ifindex = vif6_table[ct].dev->ifindex;
+                        nhp->rtnh_ifindex = init_net.ipv6.vif6_table[ct].dev->ifindex;
                         nhp->rtnh_len = sizeof(*nhp);
                 }
         }