[IPV4]: fib_trie: Use ERR_PTR to handle errno return

Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 57 insertions, 62 deletions

diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 6f818cc7efd0..914a4c2aae42 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -167,8 +167,8 @@ static void put_child(struct trie *t, struct tnode *tn, int i, struct node *n);
 static void tnode_put_child_reorg(struct tnode *tn, int i, struct node *n, int wasfull);
 static int tnode_child_length(struct tnode *tn);
 static struct node *resize(struct trie *t, struct tnode *tn);
-static struct tnode *inflate(struct trie *t, struct tnode *tn, int *err);
-static struct tnode *halve(struct trie *t, struct tnode *tn, int *err);
+static struct tnode *inflate(struct trie *t, struct tnode *tn);
+static struct tnode *halve(struct trie *t, struct tnode *tn);
 static void tnode_free(struct tnode *tn);
 static void trie_dump_seq(struct seq_file *seq, struct trie *t);
 extern struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio);
@@ -457,6 +457,7 @@ static struct node *resize(struct trie *t, struct tnode *tn)
 {
         int i;
         int err = 0;
+        struct tnode *old_tn;
 
         if (!tn)
                 return NULL;
@@ -559,9 +560,10 @@ static struct node *resize(struct trie *t, struct tnode *tn)
                50 * (tn->full_children + tnode_child_length(tn) - tn->empty_children) >=
                                 inflate_threshold * tnode_child_length(tn))) {
 
-                tn = inflate(t, tn, &err);
-
-                if (err) {
+                old_tn = tn;
+                tn = inflate(t, tn);
+                if (IS_ERR(tn)) {
+                        tn = old_tn;
 #ifdef CONFIG_IP_FIB_TRIE_STATS
                         t->stats.resize_node_skipped++;
 #endif
@@ -581,9 +583,10 @@ static struct node *resize(struct trie *t, struct tnode *tn)
                100 * (tnode_child_length(tn) - tn->empty_children) <
                halve_threshold * tnode_child_length(tn)) {
 
-                tn = halve(t, tn, &err);
-
-                if (err) {
+                old_tn = tn;
+                tn = halve(t, tn);
+                if (IS_ERR(tn)) {
+                        tn = old_tn;
 #ifdef CONFIG_IP_FIB_TRIE_STATS
                         t->stats.resize_node_skipped++;
 #endif
@@ -618,7 +621,7 @@ static struct node *resize(struct trie *t, struct tnode *tn)
         return (struct node *) tn;
 }
 
-static struct tnode *inflate(struct trie *t, struct tnode *tn, int *err)
+static struct tnode *inflate(struct trie *t, struct tnode *tn)
 {
         struct tnode *inode;
         struct tnode *oldtnode = tn;
@@ -629,10 +632,8 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn, int *err)
 
         tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1);
 
-        if (!tn) {
-                *err = -ENOMEM;
-                return oldtnode;
-        }
+        if (!tn) 
+                return ERR_PTR(-ENOMEM);
 
         /*
          * Preallocate and store tnodes before the actual work so we
@@ -653,39 +654,22 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn, int *err)
 
                         left = tnode_new(inode->key&(~m), inode->pos + 1,
                                          inode->bits - 1);
-
-                        if (!left) {
-                                *err = -ENOMEM;
-                                break;
-                        }
+                        if (!left)
+                                goto nomem;
 
                         right = tnode_new(inode->key|m, inode->pos + 1,
                                           inode->bits - 1);
 
-                        if (!right) {
-                                *err = -ENOMEM;
-                                break;
-                        }
+                        if (!right) {
+                                tnode_free(left);
+                                goto nomem;
+                        }
 
                         put_child(t, tn, 2*i, (struct node *) left);
                         put_child(t, tn, 2*i+1, (struct node *) right);
                 }
         }
 
-        if (*err) {
-                int size = tnode_child_length(tn);
-                int j;
-
-                for (j = 0; j < size; j++)
-                        if (tn->child[j])
-                                tnode_free((struct tnode *)tn->child[j]);
-
-                tnode_free(tn);
-
-                *err = -ENOMEM;
-                return oldtnode;
-        }
-
         for (i = 0; i < olen; i++) {
                 struct node *node = tnode_get_child(oldtnode, i);
                 struct tnode *left, *right;
@@ -763,9 +747,22 @@ static struct tnode *inflate(struct trie *t, struct tnode *tn, int *err)
         }
         tnode_free(oldtnode);
         return tn;
+nomem:
+        {
+                int size = tnode_child_length(tn);
+                int j;
+
+                for(j = 0; j < size; j++)
+                        if (tn->child[j])
+                                tnode_free((struct tnode *)tn->child[j]);
+
+                tnode_free(tn);
+        
+                return ERR_PTR(-ENOMEM);
+        }
 }
 
-static struct tnode *halve(struct trie *t, struct tnode *tn, int *err)
+static struct tnode *halve(struct trie *t, struct tnode *tn)
 {
         struct tnode *oldtnode = tn;
         struct node *left, *right;
@@ -776,10 +773,8 @@ static struct tnode *halve(struct trie *t, struct tnode *tn, int *err)
 
         tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1);
 
-        if (!tn) {
-                *err = -ENOMEM;
-                return oldtnode;
-        }
+        if (!tn)
+                return ERR_PTR(-ENOMEM);
 
         /*
          * Preallocate and store tnodes before the actual work so we
@@ -794,29 +789,16 @@ static struct tnode *halve(struct trie *t, struct tnode *tn, int *err)
 
                 /* Two nonempty children */
                 if (left && right)  {
-                        struct tnode *newBinNode =
-                                tnode_new(left->key, tn->pos + tn->bits, 1);
-
-                        if (!newBinNode) {
-                                *err = -ENOMEM;
-                                break;
-                        }
-                        put_child(t, tn, i/2, (struct node *)newBinNode);
+                        struct tnode *newn;
+  
+                        newn = tnode_new(left->key, tn->pos + tn->bits, 1);
+  
+                        if (!newn) 
+                                goto nomem;
+  
+                        put_child(t, tn, i/2, (struct node *)newn);
                 }
-        }
 
-        if (*err) {
-                int size = tnode_child_length(tn);
-                int j;
-
-                for (j = 0; j < size; j++)
-                        if (tn->child[j])
-                                tnode_free((struct tnode *)tn->child[j]);
-
-                tnode_free(tn);
-
-                *err = -ENOMEM;
-                return oldtnode;
         }
 
         for (i = 0; i < olen; i += 2) {
@@ -850,6 +832,19 @@ static struct tnode *halve(struct trie *t, struct tnode *tn, int *err)
         }
         tnode_free(oldtnode);
         return tn;
+nomem:
+        {
+                int size = tnode_child_length(tn);
+                int j;
+
+                for(j = 0; j < size; j++)
+                        if (tn->child[j])
+                                tnode_free((struct tnode *)tn->child[j]);
+
+                tnode_free(tn);
+        
+                return ERR_PTR(-ENOMEM);
+        }
 }
 
 static void trie_init(struct trie *t)