[IPV6]: Increase number of possible routing tables to 2^32

Increase number of possible routing tables to 2^32 by replacing iterations
over all possible table IDs by hash table walking.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index 9bfa3cc..01bfe40 100644 (file)
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -137,6 +137,13 @@ extern int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *a
 extern int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 extern int inet6_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);
 
+struct rt6_rtnl_dump_arg
+{
+       struct sk_buff *skb;
+       struct netlink_callback *cb;
+};
+
+extern int rt6_dump_route(struct rt6_info *rt, void *p_arg);
 extern void rt6_ifdown(struct net_device *dev);
 extern void rt6_mtu_change(struct net_device *dev, unsigned mtu);
 

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 1f23161..bececbe 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -158,7 +158,26 @@ static struct fib6_table fib6_main_tbl = {
 };
 
 #ifdef CONFIG_IPV6_MULTIPLE_TABLES
+#define FIB_TABLE_HASHSZ 256
+#else
+#define FIB_TABLE_HASHSZ 1
+#endif
+static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
+
+static void fib6_link_table(struct fib6_table *tb)
+{
+       unsigned int h;
+
+       h = tb->tb6_id & (FIB_TABLE_HASHSZ - 1);
 
+       /*
+        * No protection necessary, this is the only list mutatation
+        * operation, tables never disappear once they exist.
+        */
+       hlist_add_head_rcu(&tb->tb6_hlist, &fib_table_hash[h]);
+}
+
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
 static struct fib6_table fib6_local_tbl = {
        .tb6_id         = RT6_TABLE_LOCAL,
        .tb6_lock       = RW_LOCK_UNLOCKED,
@@ -168,9 +187,6 @@ static struct fib6_table fib6_local_tbl = {
        },
 };
 
-#define FIB_TABLE_HASHSZ 256
-static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
-
 static struct fib6_table *fib6_alloc_table(u32 id)
 {
        struct fib6_table *table;
@@ -186,19 +202,6 @@ static struct fib6_table *fib6_alloc_table(u32 id)
        return table;
 }
 
-static void fib6_link_table(struct fib6_table *tb)
-{
-       unsigned int h;
-
-       h = tb->tb6_id & (FIB_TABLE_HASHSZ - 1);
-
-       /*
-        * No protection necessary, this is the only list mutatation
-        * operation, tables never disappear once they exist.
-        */
-       hlist_add_head_rcu(&tb->tb6_hlist, &fib_table_hash[h]);
-}
-
 struct fib6_table *fib6_new_table(u32 id)
 {
        struct fib6_table *tb;
@@ -263,10 +266,135 @@ struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags,
 
 static void __init fib6_tables_init(void)
 {
+       fib6_link_table(&fib6_main_tbl);
 }
 
 #endif
 
+static int fib6_dump_node(struct fib6_walker_t *w)
+{
+       int res;
+       struct rt6_info *rt;
+
+       for (rt = w->leaf; rt; rt = rt->u.next) {
+               res = rt6_dump_route(rt, w->args);
+               if (res < 0) {
+                       /* Frame is full, suspend walking */
+                       w->leaf = rt;
+                       return 1;
+               }
+               BUG_TRAP(res!=0);
+       }
+       w->leaf = NULL;
+       return 0;
+}
+
+static void fib6_dump_end(struct netlink_callback *cb)
+{
+       struct fib6_walker_t *w = (void*)cb->args[2];
+
+       if (w) {
+               cb->args[2] = 0;
+               kfree(w);
+       }
+       cb->done = (void*)cb->args[3];
+       cb->args[1] = 3;
+}
+
+static int fib6_dump_done(struct netlink_callback *cb)
+{
+       fib6_dump_end(cb);
+       return cb->done ? cb->done(cb) : 0;
+}
+
+static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
+                          struct netlink_callback *cb)
+{
+       struct fib6_walker_t *w;
+       int res;
+
+       w = (void *)cb->args[2];
+       w->root = &table->tb6_root;
+
+       if (cb->args[4] == 0) {
+               read_lock_bh(&table->tb6_lock);
+               res = fib6_walk(w);
+               read_unlock_bh(&table->tb6_lock);
+               if (res > 0)
+                       cb->args[4] = 1;
+       } else {
+               read_lock_bh(&table->tb6_lock);
+               res = fib6_walk_continue(w);
+               read_unlock_bh(&table->tb6_lock);
+               if (res != 0) {
+                       if (res < 0)
+                               fib6_walker_unlink(w);
+                       goto end;
+               }
+               fib6_walker_unlink(w);
+               cb->args[4] = 0;
+       }
+end:
+       return res;
+}
+
+int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
+{
+       unsigned int h, s_h;
+       unsigned int e = 0, s_e;
+       struct rt6_rtnl_dump_arg arg;
+       struct fib6_walker_t *w;
+       struct fib6_table *tb;
+       struct hlist_node *node;
+       int res = 0;
+
+       s_h = cb->args[0];
+       s_e = cb->args[1];
+
+       w = (void *)cb->args[2];
+       if (w == NULL) {
+               /* New dump:
+                *
+                * 1. hook callback destructor.
+                */
+               cb->args[3] = (long)cb->done;
+               cb->done = fib6_dump_done;
+
+               /*
+                * 2. allocate and initialize walker.
+                */
+               w = kzalloc(sizeof(*w), GFP_ATOMIC);
+               if (w == NULL)
+                       return -ENOMEM;
+               w->func = fib6_dump_node;
+               cb->args[2] = (long)w;
+       }
+
+       arg.skb = skb;
+       arg.cb = cb;
+       w->args = &arg;
+
+       for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {
+               e = 0;
+               hlist_for_each_entry(tb, node, &fib_table_hash[h], tb6_hlist) {
+                       if (e < s_e)
+                               goto next;
+                       res = fib6_dump_table(tb, skb, cb);
+                       if (res != 0)
+                               goto out;
+next:
+                       e++;
+               }
+       }
+out:
+       cb->args[1] = e;
+       cb->args[0] = h;
+
+       res = res < 0 ? res : skb->len;
+       if (res <= 0)
+               fib6_dump_end(cb);
+       return res;
+}
 
 /*
  *     Routing Table
@@ -1187,17 +1315,20 @@ static void fib6_clean_tree(struct fib6_node *root,
 void fib6_clean_all(int (*func)(struct rt6_info *, void *arg),
                    int prune, void *arg)
 {
-       int i;
        struct fib6_table *table;
+       struct hlist_node *node;
+       unsigned int h;
 
-       for (i = FIB6_TABLE_MIN; i <= FIB6_TABLE_MAX; i++) {
-               table = fib6_get_table(i);
-               if (table != NULL) {
+       rcu_read_lock();
+       for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
+               hlist_for_each_entry_rcu(table, node, &fib_table_hash[h],
+                                        tb6_hlist) {
                        write_lock_bh(&table->tb6_lock);
                        fib6_clean_tree(&table->tb6_root, func, prune, arg);
                        write_unlock_bh(&table->tb6_lock);
                }
        }
+       rcu_read_unlock();
 }
 
 static int fib6_prune_clone(struct rt6_info *rt, void *arg)

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 843c550..9ce2827 100644 (file)
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1874,12 +1874,6 @@ int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg)
                             rtm_get_table(arg, r->rtm_table));
 }
 
-struct rt6_rtnl_dump_arg
-{
-       struct sk_buff *skb;
-       struct netlink_callback *cb;
-};
-
 static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,
                         struct in6_addr *dst, struct in6_addr *src,
                         int iif, int type, u32 pid, u32 seq,
@@ -1976,7 +1970,7 @@ rtattr_failure:
        return -1;
 }
 
-static int rt6_dump_route(struct rt6_info *rt, void *p_arg)
+int rt6_dump_route(struct rt6_info *rt, void *p_arg)
 {
        struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;
        int prefix;
@@ -1992,126 +1986,6 @@ static int rt6_dump_route(struct rt6_info *rt, void *p_arg)
                     prefix, NLM_F_MULTI);
 }
 
-static int fib6_dump_node(struct fib6_walker_t *w)
-{
-       int res;
-       struct rt6_info *rt;
-
-       for (rt = w->leaf; rt; rt = rt->u.next) {
-               res = rt6_dump_route(rt, w->args);
-               if (res < 0) {
-                       /* Frame is full, suspend walking */
-                       w->leaf = rt;
-                       return 1;
-               }
-               BUG_TRAP(res!=0);
-       }
-       w->leaf = NULL;
-       return 0;
-}
-
-static void fib6_dump_end(struct netlink_callback *cb)
-{
-       struct fib6_walker_t *w = (void*)cb->args[0];
-
-       if (w) {
-               cb->args[0] = 0;
-               kfree(w);
-       }
-       cb->done = (void*)cb->args[1];
-       cb->args[1] = 0;
-}
-
-static int fib6_dump_done(struct netlink_callback *cb)
-{
-       fib6_dump_end(cb);
-       return cb->done ? cb->done(cb) : 0;
-}
-
-int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
-{
-       struct fib6_table *table;
-       struct rt6_rtnl_dump_arg arg;
-       struct fib6_walker_t *w;
-       int i, res = 0;
-
-       arg.skb = skb;
-       arg.cb = cb;
-
-       /*
-        * cb->args[0] = pointer to walker structure
-        * cb->args[1] = saved cb->done() pointer
-        * cb->args[2] = current table being dumped
-        */
-
-       w = (void*)cb->args[0];
-       if (w == NULL) {
-               /* New dump:
-                * 
-                * 1. hook callback destructor.
-                */
-               cb->args[1] = (long)cb->done;
-               cb->done = fib6_dump_done;
-
-               /*
-                * 2. allocate and initialize walker.
-                */
-               w = kzalloc(sizeof(*w), GFP_ATOMIC);
-               if (w == NULL)
-                       return -ENOMEM;
-               w->func = fib6_dump_node;
-               w->args = &arg;
-               cb->args[0] = (long)w;
-               cb->args[2] = FIB6_TABLE_MIN;
-       } else {
-               w->args = &arg;
-               i = cb->args[2];
-               if (i > FIB6_TABLE_MAX)
-                       goto end;
-
-               table = fib6_get_table(i);
-               if (table != NULL) {
-                       read_lock_bh(&table->tb6_lock);
-                       w->root = &table->tb6_root;
-                       res = fib6_walk_continue(w);
-                       read_unlock_bh(&table->tb6_lock);
-                       if (res != 0) {
-                               if (res < 0)
-                                       fib6_walker_unlink(w);
-                               goto end;
-                       }
-               }
-
-               fib6_walker_unlink(w);
-               cb->args[2] = ++i;
-       }
-
-       for (i = cb->args[2]; i <= FIB6_TABLE_MAX; i++) {
-               table = fib6_get_table(i);
-               if (table == NULL)
-                       continue;
-
-               read_lock_bh(&table->tb6_lock);
-               w->root = &table->tb6_root;
-               res = fib6_walk(w);
-               read_unlock_bh(&table->tb6_lock);
-               if (res)
-                       break;
-       }
-end:
-       cb->args[2] = i;
-
-       res = res < 0 ? res : skb->len;
-       /* res < 0 is an error. (really, impossible)
-          res == 0 means that dump is complete, but skb still can contain data.
-          res > 0 dump is not complete, but frame is full.
-        */
-       /* Destroy walker, if dump of this table is complete. */
-       if (res <= 0)
-               fib6_dump_end(cb);
-       return res;
-}
-
 int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
 {
        struct rtattr **rta = arg;