[IPV4]: FIB cleanup, fib_find_alias()

Abstract out fib_node arg usage in fib_find_alias(),
move to fib_semantics.c
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/fib_hash.c

@@ -399,26 +399,6 @@ static struct fib_node *fib_find_node(struct fn_zone *fz, u32 key)
 	return NULL;
 }
 
-/* Return the first fib alias matching TOS with
- * priority less than or equal to PRIO.
- */
-static struct fib_alias *fib_find_alias(struct fib_node *fn, u8 tos, u32 prio)
-{
-	if (fn) {
-		struct list_head *head = &fn->fn_alias;
-		struct fib_alias *fa;
-
-		list_for_each_entry(fa, head, fa_list) {
-			if (fa->fa_tos > tos)
-				continue;
-			if (fa->fa_info->fib_priority >= prio ||
-			    fa->fa_tos < tos)
-				return fa;
-		}
-	}
-	return NULL;
-}
-
 static int
 fn_hash_insert(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
 	       struct nlmsghdr *n, struct netlink_skb_parms *req)
@@ -458,7 +438,11 @@ fn_hash_insert(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
 		fn_rehash_zone(fz);
 
 	f = fib_find_node(fz, key);
-	fa = fib_find_alias(f, tos, fi->fib_priority);
+
+	if (!f)
+		fa = NULL;
+	else
+		fa = fib_find_alias(&f->fn_alias, tos, fi->fib_priority);
 
 	/* Now fa, if non-NULL, points to the first fib alias
 	 * with the same keys [prefix,tos,priority], if such key already
@@ -598,7 +582,11 @@ fn_hash_delete(struct fib_table *tb, struct rtmsg *r, struct kern_rta *rta,
 	}
 
 	f = fib_find_node(fz, key);
-	fa = fib_find_alias(f, tos, 0);
+
+	if (!f)
+		fa = NULL;
+	else
+		fa = fib_find_alias(&f->fn_alias, tos, 0);
 	if (!fa)
 		return -ESRCH;
 

net/ipv4/fib_lookup.h

@@ -33,5 +33,7 @@ extern int fib_dump_info(struct sk_buff *skb, u32 pid, u32 seq, int event,
 extern void rtmsg_fib(int event, u32 key, struct fib_alias *fa,
 		      int z, int tb_id,
 		      struct nlmsghdr *n, struct netlink_skb_parms *req);
+extern struct fib_alias *fib_find_alias(struct list_head *fah,
+					u8 tos, u32 prio);
 
 #endif /* _FIB_LOOKUP_H */

net/ipv4/fib_semantics.c

@@ -297,6 +297,24 @@ void rtmsg_fib(int event, u32 key, struct fib_alias *fa,
 		netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 }
 
+/* Return the first fib alias matching TOS with
+ * priority less than or equal to PRIO.
+ */
+struct fib_alias *fib_find_alias(struct list_head *fah, u8 tos, u32 prio)
+{
+	if (fah) {
+		struct fib_alias *fa;
+		list_for_each_entry(fa, fah, fa_list) {
+			if (fa->fa_tos > tos)
+				continue;
+			if (fa->fa_info->fib_priority >= prio ||
+			    fa->fa_tos < tos)
+				return fa;
+		}
+	}
+	return NULL;
+}
+
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 
 static u32 fib_get_attr32(struct rtattr *attr, int attrlen, int type)