fib_trie: Merge leaf into tnode

This change makes it so that leaf and tnode are the same struct.  As a
result there is no need for rt_trie_node anymore since everyting can be
merged into tnode.

On 32b systems this results in the leaf being 4 bytes larger, however I
don't know if that is really an issue as this and an eariler patch that
added bits & pos have increased the size from 20 to 28.  If I am not
mistaken slub/slab allocate on power of 2 sizes so 20 was likely being
rounded up to 32 anyway.

Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index d1a9907901cba65518bbd9b07bd34d72366153fc..94c929f6c7529218116540eb67278779df1495f9 100644 (file)
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -96,32 +96,16 @@ struct tnode {
        unsigned char pos;              /* 2log(KEYLENGTH) bits needed */
        struct tnode __rcu *parent;
        struct rcu_head rcu;
-       /* everything above this comment must be the same as rt_trie_node */
-       unsigned int full_children;     /* KEYLENGTH bits needed */
-       unsigned int empty_children;    /* KEYLENGTH bits needed */
-       struct rt_trie_node __rcu *child[0];
-};
-
-/* This struct represents the shared bits between tnode and leaf.  If any
- * ordering is changed here is must also be updated in tnode and leaf as
- * well.
- */
-struct rt_trie_node {
-       t_key key;
-       unsigned char bits;
-       unsigned char pos;
-       struct tnode __rcu *parent;
-       struct rcu_head rcu;
-};
-
-struct leaf {
-       t_key key;
-       unsigned char bits;
-       unsigned char pos;
-       struct tnode __rcu *parent;
-       struct rcu_head rcu;
-       /* everything above this comment must be the same as rt_trie_node */
-       struct hlist_head list;
+       union {
+               /* The fields in this struct are valid if bits > 0 (TNODE) */
+               struct {
+                       unsigned int full_children;  /* KEYLENGTH bits needed */
+                       unsigned int empty_children; /* KEYLENGTH bits needed */
+                       struct tnode __rcu *child[0];
+               };
+               /* This list pointer if valid if bits == 0 (LEAF) */
+               struct hlist_head list;
+       };
 };
 
 struct leaf_info {
@@ -154,15 +138,15 @@ struct trie_stat {
 };
 
 struct trie {
-       struct rt_trie_node __rcu *trie;
+       struct tnode __rcu *trie;
 #ifdef CONFIG_IP_FIB_TRIE_STATS
        struct trie_use_stats __percpu *stats;
 #endif
 };
 
-static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n,
+static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n,
                                  int wasfull);
-static struct rt_trie_node *resize(struct trie *t, struct tnode *tn);
+static struct tnode *resize(struct trie *t, struct tnode *tn);
 static struct tnode *inflate(struct trie *t, struct tnode *tn);
 static struct tnode *halve(struct trie *t, struct tnode *tn);
 /* tnodes to free after resize(); protected by RTNL */
@@ -186,10 +170,10 @@ static struct kmem_cache *trie_leaf_kmem __read_mostly;
 #define node_parent_rcu(n) rcu_dereference_rtnl((n)->parent)
 
 /* wrapper for rcu_assign_pointer */
-static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr)
+static inline void node_set_parent(struct tnode *n, struct tnode *tp)
 {
-       if (node)
-               rcu_assign_pointer(node->parent, ptr);
+       if (n)
+               rcu_assign_pointer(n->parent, tp);
 }
 
 #define NODE_INIT_PARENT(n, p) RCU_INIT_POINTER((n)->parent, p)
@@ -205,7 +189,7 @@ static inline int tnode_child_length(const struct tnode *tn)
 /*
  * caller must hold RTNL
  */
-static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsigned int i)
+static inline struct tnode *tnode_get_child(const struct tnode *tn, unsigned int i)
 {
        BUG_ON(i >= tnode_child_length(tn));
 
@@ -215,7 +199,7 @@ static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsig
 /*
  * caller must hold RCU read lock or RTNL
  */
-static inline struct rt_trie_node *tnode_get_child_rcu(const struct tnode *tn, unsigned int i)
+static inline struct tnode *tnode_get_child_rcu(const struct tnode *tn, unsigned int i)
 {
        BUG_ON(i >= tnode_child_length(tn));
 
@@ -340,11 +324,11 @@ static inline void alias_free_mem_rcu(struct fib_alias *fa)
 }
 
 #define TNODE_KMALLOC_MAX \
-       ilog2((PAGE_SIZE - sizeof(struct tnode)) / sizeof(struct rt_trie_node *))
+       ilog2((PAGE_SIZE - sizeof(struct tnode)) / sizeof(struct tnode *))
 
 static void __node_free_rcu(struct rcu_head *head)
 {
-       struct rt_trie_node *n = container_of(head, struct rt_trie_node, rcu);
+       struct tnode *n = container_of(head, struct tnode, rcu);
 
        if (IS_LEAF(n))
                kmem_cache_free(trie_leaf_kmem, n);
@@ -395,9 +379,9 @@ static void tnode_free_flush(void)
        }
 }
 
-static struct leaf *leaf_new(t_key key)
+static struct tnode *leaf_new(t_key key)
 {
-       struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
+       struct tnode *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL);
        if (l) {
                l->parent = NULL;
                /* set key and pos to reflect full key value
@@ -444,7 +428,7 @@ static struct tnode *tnode_new(t_key key, int pos, int bits)
        }
 
        pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode),
-                sizeof(struct rt_trie_node *) << bits);
+                sizeof(struct tnode *) << bits);
        return tn;
 }
 
@@ -453,13 +437,13 @@ static struct tnode *tnode_new(t_key key, int pos, int bits)
  * and no bits are skipped. See discussion in dyntree paper p. 6
  */
 
-static inline int tnode_full(const struct tnode *tn, const struct rt_trie_node *n)
+static inline int tnode_full(const struct tnode *tn, const struct tnode *n)
 {
        return n && IS_TNODE(n) && (n->pos == (tn->pos + tn->bits));
 }
 
 static inline void put_child(struct tnode *tn, int i,
-                            struct rt_trie_node *n)
+                            struct tnode *n)
 {
        tnode_put_child_reorg(tn, i, n, -1);
 }
@@ -469,10 +453,10 @@ static inline void put_child(struct tnode *tn, int i,
   * Update the value of full_children and empty_children.
   */
 
-static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n,
+static void tnode_put_child_reorg(struct tnode *tn, int i, struct tnode *n,
                                  int wasfull)
 {
-       struct rt_trie_node *chi = rtnl_dereference(tn->child[i]);
+       struct tnode *chi = rtnl_dereference(tn->child[i]);
        int isfull;
 
        BUG_ON(i >= 1<<tn->bits);
@@ -499,10 +483,9 @@ static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *
 }
 
 #define MAX_WORK 10
-static struct rt_trie_node *resize(struct trie *t, struct tnode *tn)
+static struct tnode *resize(struct trie *t, struct tnode *tn)
 {
-       struct rt_trie_node *n = NULL;
-       struct tnode *old_tn;
+       struct tnode *old_tn, *n = NULL;
        int inflate_threshold_use;
        int halve_threshold_use;
        int max_work;
@@ -614,7 +597,7 @@ static struct rt_trie_node *resize(struct trie *t, struct tnode *tn)
 
        /* Return if at least one inflate is run */
        if (max_work != MAX_WORK)
-               return (struct rt_trie_node *) tn;
+               return tn;
 
        /*
         * Halve as long as the number of empty children in this
@@ -650,13 +633,13 @@ no_children:
                tnode_free_safe(tn);
                return n;
        }
-       return (struct rt_trie_node *) tn;
+       return tn;
 }
 
 
 static void tnode_clean_free(struct tnode *tn)
 {
-       struct rt_trie_node *tofree;
+       struct tnode *tofree;
        int i;
 
        for (i = 0; i < tnode_child_length(tn); i++) {
@@ -667,10 +650,10 @@ static void tnode_clean_free(struct tnode *tn)
        node_free(tn);
 }
 
-static struct tnode *inflate(struct trie *t, struct tnode *tn)
+static struct tnode *inflate(struct trie *t, struct tnode *oldtnode)
 {
-       struct tnode *oldtnode = tn;
-       int olen = tnode_child_length(tn);
+       int olen = tnode_child_length(oldtnode);
+       struct tnode *tn;
        int i;
 
        pr_debug("In inflate\n");
@@ -690,11 +673,8 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn)
        for (i = 0; i < olen; i++) {
                struct tnode *inode;
 
-               inode = (struct tnode *) tnode_get_child(oldtnode, i);
-               if (inode &&
-                   IS_TNODE(inode) &&
-                   inode->pos == oldtnode->pos + oldtnode->bits &&
-                   inode->bits > 1) {
+               inode = tnode_get_child(oldtnode, i);
+               if (tnode_full(oldtnode, inode) && inode->bits > 1) {
                        struct tnode *left, *right;
                        t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos;
 
@@ -711,33 +691,29 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn)
                                goto nomem;
                        }
 
-                       put_child(tn, 2*i, (struct rt_trie_node *) left);
-                       put_child(tn, 2*i+1, (struct rt_trie_node *) right);
+                       put_child(tn, 2*i, left);
+                       put_child(tn, 2*i+1, right);
                }
        }
 
        for (i = 0; i < olen; i++) {
-               struct tnode *inode;
-               struct rt_trie_node *node = tnode_get_child(oldtnode, i);
+               struct tnode *inode = tnode_get_child(oldtnode, i);
                struct tnode *left, *right;
                int size, j;
 
                /* An empty child */
-               if (node == NULL)
+               if (inode == NULL)
                        continue;
 
                /* A leaf or an internal node with skipped bits */
-
-               if (IS_LEAF(node) || (node->pos > (tn->pos + tn->bits - 1))) {
+               if (!tnode_full(oldtnode, inode)) {
                        put_child(tn,
-                               tkey_extract_bits(node->key, oldtnode->pos, oldtnode->bits + 1),
-                               node);
+                               tkey_extract_bits(inode->key, tn->pos, tn->bits),
+                               inode);
                        continue;
                }
 
                /* An internal node with two children */
-               inode = (struct tnode *) node;
-
                if (inode->bits == 1) {
                        put_child(tn, 2*i, rtnl_dereference(inode->child[0]));
                        put_child(tn, 2*i+1, rtnl_dereference(inode->child[1]));
@@ -769,12 +745,12 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn)
                 *   bit to zero.
                 */
 
-               left = (struct tnode *) tnode_get_child(tn, 2*i);
+               left = tnode_get_child(tn, 2*i);
                put_child(tn, 2*i, NULL);
 
                BUG_ON(!left);
 
-               right = (struct tnode *) tnode_get_child(tn, 2*i+1);
+               right = tnode_get_child(tn, 2*i+1);
                put_child(tn, 2*i+1, NULL);
 
                BUG_ON(!right);
@@ -796,12 +772,11 @@ nomem:
        return ERR_PTR(-ENOMEM);
 }
 
-static struct tnode *halve(struct trie *t, struct tnode *tn)
+static struct tnode *halve(struct trie *t, struct tnode *oldtnode)
 {
-       struct tnode *oldtnode = tn;
-       struct rt_trie_node *left, *right;
+       int olen = tnode_child_length(oldtnode);
+       struct tnode *tn, *left, *right;
        int i;
-       int olen = tnode_child_length(tn);
 
        pr_debug("In halve\n");
 
@@ -830,7 +805,7 @@ static struct tnode *halve(struct trie *t, struct tnode *tn)
                        if (!newn)
                                goto nomem;
 
-                       put_child(tn, i/2, (struct rt_trie_node *)newn);
+                       put_child(tn, i/2, newn);
                }
 
        }
@@ -855,7 +830,7 @@ static struct tnode *halve(struct trie *t, struct tnode *tn)
                }
 
                /* Two nonempty children */
-               newBinNode = (struct tnode *) tnode_get_child(tn, i/2);
+               newBinNode = tnode_get_child(tn, i/2);
                put_child(tn, i/2, NULL);
                put_child(newBinNode, 0, left);
                put_child(newBinNode, 1, right);
@@ -871,7 +846,7 @@ nomem:
 /* readside must use rcu_read_lock currently dump routines
  via get_fa_head and dump */
 
-static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
+static struct leaf_info *find_leaf_info(struct tnode *l, int plen)
 {
        struct hlist_head *head = &l->list;
        struct leaf_info *li;
@@ -883,7 +858,7 @@ static struct leaf_info *find_leaf_info(struct leaf *l, int plen)
        return NULL;
 }
 
-static inline struct list_head *get_fa_head(struct leaf *l, int plen)
+static inline struct list_head *get_fa_head(struct tnode *l, int plen)
 {
        struct leaf_info *li = find_leaf_info(l, plen);
 
@@ -915,32 +890,25 @@ static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new)
 
 /* rcu_read_lock needs to be hold by caller from readside */
 
-static struct leaf *
-fib_find_node(struct trie *t, u32 key)
+static struct tnode *fib_find_node(struct trie *t, u32 key)
 {
-       int pos;
-       struct tnode *tn;
-       struct rt_trie_node *n;
-
-       pos = 0;
-       n = rcu_dereference_rtnl(t->trie);
+       struct tnode *n = rcu_dereference_rtnl(t->trie);
+       int pos = 0;
 
        while (n && IS_TNODE(n)) {
-               tn = (struct tnode *) n;
-
-               if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
-                       pos = tn->pos + tn->bits;
-                       n = tnode_get_child_rcu(tn,
+               if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) {
+                       pos = n->pos + n->bits;
+                       n = tnode_get_child_rcu(n,
                                                tkey_extract_bits(key,
-                                                                 tn->pos,
-                                                                 tn->bits));
+                                                                 n->pos,
+                                                                 n->bits));
                } else
                        break;
        }
        /* Case we have found a leaf. Compare prefixes */
 
        if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key))
-               return (struct leaf *)n;
+               return n;
 
        return NULL;
 }
@@ -956,14 +924,13 @@ static void trie_rebalance(struct trie *t, struct tnode *tn)
        while (tn != NULL && (tp = node_parent(tn)) != NULL) {
                cindex = tkey_extract_bits(key, tp->pos, tp->bits);
                wasfull = tnode_full(tp, tnode_get_child(tp, cindex));
-               tn = (struct tnode *)resize(t, tn);
+               tn = resize(t, tn);
 
-               tnode_put_child_reorg(tp, cindex,
-                                     (struct rt_trie_node *)tn, wasfull);
+               tnode_put_child_reorg(tp, cindex, tn, wasfull);
 
                tp = node_parent(tn);
                if (!tp)
-                       rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+                       rcu_assign_pointer(t->trie, tn);
 
                tnode_free_flush();
                if (!tp)
@@ -973,9 +940,9 @@ static void trie_rebalance(struct trie *t, struct tnode *tn)
 
        /* Handle last (top) tnode */
        if (IS_TNODE(tn))
-               tn = (struct tnode *)resize(t, tn);
+               tn = resize(t, tn);
 
-       rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+       rcu_assign_pointer(t->trie, tn);
        tnode_free_flush();
 }
 
@@ -985,8 +952,8 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
 {
        int pos, newpos;
        struct tnode *tp = NULL, *tn = NULL;
-       struct rt_trie_node *n;
-       struct leaf *l;
+       struct tnode *n;
+       struct tnode *l;
        int missbit;
        struct list_head *fa_head = NULL;
        struct leaf_info *li;
@@ -1014,17 +981,15 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
         */
 
        while (n && IS_TNODE(n)) {
-               tn = (struct tnode *) n;
-
-               if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) {
-                       tp = tn;
-                       pos = tn->pos + tn->bits;
-                       n = tnode_get_child(tn,
+               if (tkey_sub_equals(n->key, pos, n->pos-pos, key)) {
+                       tp = n;
+                       pos = n->pos + n->bits;
+                       n = tnode_get_child(n,
                                            tkey_extract_bits(key,
-                                                             tn->pos,
-                                                             tn->bits));
+                                                             n->pos,
+                                                             n->bits));
 
-                       BUG_ON(n && node_parent(n) != tn);
+                       BUG_ON(n && node_parent(n) != tp);
                } else
                        break;
        }
@@ -1040,14 +1005,13 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
        /* Case 1: n is a leaf. Compare prefixes */
 
        if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) {
-               l = (struct leaf *) n;
                li = leaf_info_new(plen);
 
                if (!li)
                        return NULL;
 
                fa_head = &li->falh;
-               insert_leaf_info(&l->list, li);
+               insert_leaf_info(&n->list, li);
                goto done;
        }
        l = leaf_new(key);
@@ -1068,10 +1032,10 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
        if (t->trie && n == NULL) {
                /* Case 2: n is NULL, and will just insert a new leaf */
 
-               node_set_parent((struct rt_trie_node *)l, tp);
+               node_set_parent(l, tp);
 
                cindex = tkey_extract_bits(key, tp->pos, tp->bits);
-               put_child(tp, cindex, (struct rt_trie_node *)l);
+               put_child(tp, cindex, l);
        } else {
                /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */
                /*
@@ -1094,17 +1058,17 @@ static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen)
                        return NULL;
                }
 
-               node_set_parent((struct rt_trie_node *)tn, tp);
+               node_set_parent(tn, tp);
 
                missbit = tkey_extract_bits(key, newpos, 1);
-               put_child(tn, missbit, (struct rt_trie_node *)l);
+               put_child(tn, missbit, l);
                put_child(tn, 1-missbit, n);
 
                if (tp) {
                        cindex = tkey_extract_bits(key, tp->pos, tp->bits);
-                       put_child(tp, cindex, (struct rt_trie_node *)tn);
+                       put_child(tp, cindex, tn);
                } else {
-                       rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn);
+                       rcu_assign_pointer(t->trie, tn);
                }
 
                tp = tn;
@@ -1134,7 +1098,7 @@ int fib_table_insert(struct fib_table *tb, struct fib_config *cfg)
        u8 tos = cfg->fc_tos;
        u32 key, mask;
        int err;
-       struct leaf *l;
+       struct tnode *l;
 
        if (plen > 32)
                return -EINVAL;
@@ -1292,7 +1256,7 @@ err:
 }
 
 /* should be called with rcu_read_lock */
-static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l,
+static int check_leaf(struct fib_table *tb, struct trie *t, struct tnode *l,
                      t_key key,  const struct flowi4 *flp,
                      struct fib_result *res, int fib_flags)
 {
@@ -1365,7 +1329,7 @@ int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
        struct trie_use_stats __percpu *stats = t->stats;
 #endif
        int ret;
-       struct rt_trie_node *n;
+       struct tnode *n;
        struct tnode *pn;
        unsigned int pos, bits;
        t_key key = ntohl(flp->daddr);
@@ -1387,11 +1351,11 @@ int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
 
        /* Just a leaf? */
        if (IS_LEAF(n)) {
-               ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags);
+               ret = check_leaf(tb, t, n, key, flp, res, fib_flags);
                goto found;
        }
 
-       pn = (struct tnode *) n;
+       pn = n;
        chopped_off = 0;
 
        while (pn) {
@@ -1412,13 +1376,13 @@ int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
                }
 
                if (IS_LEAF(n)) {
-                       ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags);
+                       ret = check_leaf(tb, t, n, key, flp, res, fib_flags);
                        if (ret > 0)
                                goto backtrace;
                        goto found;
                }
 
-               cn = (struct tnode *)n;
+               cn = n;
 
                /*
                 * It's a tnode, and we can do some extra checks here if we
@@ -1506,7 +1470,7 @@ int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp,
                                current_prefix_length = mp;
                }
 
-               pn = (struct tnode *)n; /* Descend */
+               pn = n; /* Descend */
                chopped_off = 0;
                continue;
 
@@ -1557,7 +1521,7 @@ EXPORT_SYMBOL_GPL(fib_table_lookup);
 /*
  * Remove the leaf and return parent.
  */
-static void trie_leaf_remove(struct trie *t, struct leaf *l)
+static void trie_leaf_remove(struct trie *t, struct tnode *l)
 {
        struct tnode *tp = node_parent(l);
 
@@ -1584,7 +1548,7 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg)
        u8 tos = cfg->fc_tos;
        struct fib_alias *fa, *fa_to_delete;
        struct list_head *fa_head;
-       struct leaf *l;
+       struct tnode *l;
        struct leaf_info *li;
 
        if (plen > 32)
@@ -1682,7 +1646,7 @@ static int trie_flush_list(struct list_head *head)
        return found;
 }
 
-static int trie_flush_leaf(struct leaf *l)
+static int trie_flush_leaf(struct tnode *l)
 {
        int found = 0;
        struct hlist_head *lih = &l->list;
@@ -1704,7 +1668,7 @@ static int trie_flush_leaf(struct leaf *l)
  * Scan for the next right leaf starting at node p->child[idx]
  * Since we have back pointer, no recursion necessary.
  */
-static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c)
+static struct tnode *leaf_walk_rcu(struct tnode *p, struct tnode *c)
 {
        do {
                t_key idx;
@@ -1720,47 +1684,46 @@ static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c)
                                continue;
 
                        if (IS_LEAF(c))
-                               return (struct leaf *) c;
+                               return c;
 
                        /* Rescan start scanning in new node */
-                       p = (struct tnode *) c;
+                       p = c;
                        idx = 0;
                }
 
                /* Node empty, walk back up to parent */
-               c = (struct rt_trie_node *) p;
+               c = p;
        } while ((p = node_parent_rcu(c)) != NULL);
 
        return NULL; /* Root of trie */
 }
 
-static struct leaf *trie_firstleaf(struct trie *t)
+static struct tnode *trie_firstleaf(struct trie *t)
 {
-       struct tnode *n = (struct tnode *)rcu_dereference_rtnl(t->trie);
+       struct tnode *n = rcu_dereference_rtnl(t->trie);
 
        if (!n)
                return NULL;
 
        if (IS_LEAF(n))          /* trie is just a leaf */
-               return (struct leaf *) n;
+               return n;
 
        return leaf_walk_rcu(n, NULL);
 }
 
-static struct leaf *trie_nextleaf(struct leaf *l)
+static struct tnode *trie_nextleaf(struct tnode *l)
 {
-       struct rt_trie_node *c = (struct rt_trie_node *) l;
-       struct tnode *p = node_parent_rcu(c);
+       struct tnode *p = node_parent_rcu(l);
 
        if (!p)
                return NULL;    /* trie with just one leaf */
 
-       return leaf_walk_rcu(p, c);
+       return leaf_walk_rcu(p, l);
 }
 
-static struct leaf *trie_leafindex(struct trie *t, int index)
+static struct tnode *trie_leafindex(struct trie *t, int index)
 {
-       struct leaf *l = trie_firstleaf(t);
+       struct tnode *l = trie_firstleaf(t);
 
        while (l && index-- > 0)
                l = trie_nextleaf(l);
@@ -1775,7 +1738,7 @@ static struct leaf *trie_leafindex(struct trie *t, int index)
 int fib_table_flush(struct fib_table *tb)
 {
        struct trie *t = (struct trie *) tb->tb_data;
-       struct leaf *l, *ll = NULL;
+       struct tnode *l, *ll = NULL;
        int found = 0;
 
        for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) {
@@ -1840,7 +1803,7 @@ static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah,
        return skb->len;
 }
 
-static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb,
+static int fn_trie_dump_leaf(struct tnode *l, struct fib_table *tb,
                        struct sk_buff *skb, struct netlink_callback *cb)
 {
        struct leaf_info *li;
@@ -1876,7 +1839,7 @@ static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb,
 int fib_table_dump(struct fib_table *tb, struct sk_buff *skb,
                   struct netlink_callback *cb)
 {
-       struct leaf *l;
+       struct tnode *l;
        struct trie *t = (struct trie *) tb->tb_data;
        t_key key = cb->args[2];
        int count = cb->args[3];
@@ -1922,7 +1885,7 @@ void __init fib_trie_init(void)
                                          0, SLAB_PANIC, NULL);
 
        trie_leaf_kmem = kmem_cache_create("ip_fib_trie",
-                                          max(sizeof(struct leaf),
+                                          max(sizeof(struct tnode),
                                               sizeof(struct leaf_info)),
                                           0, SLAB_PANIC, NULL);
 }
@@ -1965,7 +1928,7 @@ struct fib_trie_iter {
        unsigned int depth;
 };
 
-static struct rt_trie_node *fib_trie_get_next(struct fib_trie_iter *iter)
+static struct tnode *fib_trie_get_next(struct fib_trie_iter *iter)
 {
        struct tnode *tn = iter->tnode;
        unsigned int cindex = iter->index;
@@ -1979,7 +1942,7 @@ static struct rt_trie_node *fib_trie_get_next(struct fib_trie_iter *iter)
                 iter->tnode, iter->index, iter->depth);
 rescan:
        while (cindex < (1<<tn->bits)) {
-               struct rt_trie_node *n = tnode_get_child_rcu(tn, cindex);
+               struct tnode *n = tnode_get_child_rcu(tn, cindex);
 
                if (n) {
                        if (IS_LEAF(n)) {
@@ -1987,7 +1950,7 @@ rescan:
                                iter->index = cindex + 1;
                        } else {
                                /* push down one level */
-                               iter->tnode = (struct tnode *) n;
+                               iter->tnode = n;
                                iter->index = 0;
                                ++iter->depth;
                        }
@@ -1998,7 +1961,7 @@ rescan:
        }
 
        /* Current node exhausted, pop back up */
-       p = node_parent_rcu((struct rt_trie_node *)tn);
+       p = node_parent_rcu(tn);
        if (p) {
                cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1;
                tn = p;
@@ -2010,10 +1973,10 @@ rescan:
        return NULL;
 }
 
-static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter,
+static struct tnode *fib_trie_get_first(struct fib_trie_iter *iter,
                                       struct trie *t)
 {
-       struct rt_trie_node *n;
+       struct tnode *n;
 
        if (!t)
                return NULL;
@@ -2023,7 +1986,7 @@ static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter,
                return NULL;
 
        if (IS_TNODE(n)) {
-               iter->tnode = (struct tnode *) n;
+               iter->tnode = n;
                iter->index = 0;
                iter->depth = 1;
        } else {
@@ -2037,7 +2000,7 @@ static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter,
 
 static void trie_collect_stats(struct trie *t, struct trie_stat *s)
 {
-       struct rt_trie_node *n;
+       struct tnode *n;
        struct fib_trie_iter iter;
 
        memset(s, 0, sizeof(*s));
@@ -2045,7 +2008,6 @@ static void trie_collect_stats(struct trie *t, struct trie_stat *s)
        rcu_read_lock();
        for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) {
                if (IS_LEAF(n)) {
-                       struct leaf *l = (struct leaf *)n;
                        struct leaf_info *li;
 
                        s->leaves++;
@@ -2053,18 +2015,17 @@ static void trie_collect_stats(struct trie *t, struct trie_stat *s)
                        if (iter.depth > s->maxdepth)
                                s->maxdepth = iter.depth;
 
-                       hlist_for_each_entry_rcu(li, &l->list, hlist)
+                       hlist_for_each_entry_rcu(li, &n->list, hlist)
                                ++s->prefixes;
                } else {
-                       const struct tnode *tn = (const struct tnode *) n;
                        int i;
 
                        s->tnodes++;
-                       if (tn->bits < MAX_STAT_DEPTH)
-                               s->nodesizes[tn->bits]++;
+                       if (n->bits < MAX_STAT_DEPTH)
+                               s->nodesizes[n->bits]++;
 
-                       for (i = 0; i < (1<<tn->bits); i++)
-                               if (!tn->child[i])
+                       for (i = 0; i < tnode_child_length(n); i++)
+                               if (!rcu_access_pointer(n->child[i]))
                                        s->nullpointers++;
                }
        }
@@ -2088,7 +2049,7 @@ static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
        seq_printf(seq, "\tMax depth:      %u\n", stat->maxdepth);
 
        seq_printf(seq, "\tLeaves:         %u\n", stat->leaves);
-       bytes = sizeof(struct leaf) * stat->leaves;
+       bytes = sizeof(struct tnode) * stat->leaves;
 
        seq_printf(seq, "\tPrefixes:       %u\n", stat->prefixes);
        bytes += sizeof(struct leaf_info) * stat->prefixes;
@@ -2109,7 +2070,7 @@ static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat)
        seq_putc(seq, '\n');
        seq_printf(seq, "\tPointers: %u\n", pointers);
 
-       bytes += sizeof(struct rt_trie_node *) * pointers;
+       bytes += sizeof(struct tnode *) * pointers;
        seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers);
        seq_printf(seq, "Total size: %u  kB\n", (bytes + 1023) / 1024);
 }
@@ -2163,7 +2124,7 @@ static int fib_triestat_seq_show(struct seq_file *seq, void *v)
        seq_printf(seq,
                   "Basic info: size of leaf:"
                   " %Zd bytes, size of tnode: %Zd bytes.\n",
-                  sizeof(struct leaf), sizeof(struct tnode));
+                  sizeof(struct tnode), sizeof(struct tnode));
 
        for (h = 0; h < FIB_TABLE_HASHSZ; h++) {
                struct hlist_head *head = &net->ipv4.fib_table_hash[h];
@@ -2202,7 +2163,7 @@ static const struct file_operations fib_triestat_fops = {
        .release = single_release_net,
 };
 
-static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
+static struct tnode *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
 {
        struct fib_trie_iter *iter = seq->private;
        struct net *net = seq_file_net(seq);
@@ -2214,7 +2175,7 @@ static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos)
                struct fib_table *tb;
 
                hlist_for_each_entry_rcu(tb, head, tb_hlist) {
-                       struct rt_trie_node *n;
+                       struct tnode *n;
 
                        for (n = fib_trie_get_first(iter,
                                                    (struct trie *) tb->tb_data);
@@ -2243,7 +2204,7 @@ static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos)
        struct fib_table *tb = iter->tb;
        struct hlist_node *tb_node;
        unsigned int h;
-       struct rt_trie_node *n;
+       struct tnode *n;
 
        ++*pos;
        /* next node in same table */
@@ -2329,29 +2290,26 @@ static inline const char *rtn_type(char *buf, size_t len, unsigned int t)
 static int fib_trie_seq_show(struct seq_file *seq, void *v)
 {
        const struct fib_trie_iter *iter = seq->private;
-       struct rt_trie_node *n = v;
+       struct tnode *n = v;
 
        if (!node_parent_rcu(n))
                fib_table_print(seq, iter->tb);
 
        if (IS_TNODE(n)) {
-               struct tnode *tn = (struct tnode *) n;
-               __be32 prf = htonl(tn->key);
+               __be32 prf = htonl(n->key);
 
-               seq_indent(seq, iter->depth-1);
+               seq_indent(seq, iter->depth - 1);
                seq_printf(seq, "  +-- %pI4/%d %d %d %d\n",
-                          &prf, tn->pos, tn->bits, tn->full_children,
-                          tn->empty_children);
-
+                          &prf, n->pos, n->bits, n->full_children,
+                          n->empty_children);
        } else {
-               struct leaf *l = (struct leaf *) n;
                struct leaf_info *li;
-               __be32 val = htonl(l->key);
+               __be32 val = htonl(n->key);
 
                seq_indent(seq, iter->depth);
                seq_printf(seq, "  |-- %pI4\n", &val);
 
-               hlist_for_each_entry_rcu(li, &l->list, hlist) {
+               hlist_for_each_entry_rcu(li, &n->list, hlist) {
                        struct fib_alias *fa;
 
                        list_for_each_entry_rcu(fa, &li->falh, fa_list) {
@@ -2401,9 +2359,9 @@ struct fib_route_iter {
        t_key   key;
 };
 
-static struct leaf *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos)
+static struct tnode *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos)
 {
-       struct leaf *l = NULL;
+       struct tnode *l = NULL;
        struct trie *t = iter->main_trie;
 
        /* use cache location of last found key */
@@ -2448,7 +2406,7 @@ static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos)
 static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 {
        struct fib_route_iter *iter = seq->private;
-       struct leaf *l = v;
+       struct tnode *l = v;
 
        ++*pos;
        if (v == SEQ_START_TOKEN) {
@@ -2494,7 +2452,7 @@ static unsigned int fib_flag_trans(int type, __be32 mask, const struct fib_info
  */
 static int fib_route_seq_show(struct seq_file *seq, void *v)
 {
-       struct leaf *l = v;
+       struct tnode *l = v;
        struct leaf_info *li;
 
        if (v == SEQ_START_TOKEN) {