[IPV4]: Unify access to the routing tables.

Replace the direct pointers to local and main tables with
calls to fib_get_table() with appropriate argument.

This doesn't introduce additional dereferences, but makes the access to fib
tables uniform in any (CONFIG_IP_MULTIPLE_TABLES) case.

Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Acked-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 40 insertions, 28 deletions

diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 338d3ed10c31..249af662e897 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -120,16 +120,22 @@ struct fib_result_nl {
         int             err;      
 };
 
+extern struct hlist_head fib_table_hash[];
+
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 
 #define FIB_RES_NH(res)         ((res).fi->fib_nh[(res).nh_sel])
 #define FIB_RES_RESET(res)      ((res).nh_sel = 0)
 
+#define FIB_TABLE_HASHSZ 2
+
 #else /* CONFIG_IP_ROUTE_MULTIPATH */
 
 #define FIB_RES_NH(res)         ((res).fi->fib_nh[0])
 #define FIB_RES_RESET(res)
 
+#define FIB_TABLE_HASHSZ 256
+
 #endif /* CONFIG_IP_ROUTE_MULTIPATH */
 
 #define FIB_RES_PREFSRC(res)            ((res).fi->fib_prefsrc ? : __fib_res_prefsrc(&res))
@@ -156,14 +162,17 @@ struct fib_table {
 
 #ifndef CONFIG_IP_MULTIPLE_TABLES
 
-extern struct fib_table *ip_fib_local_table;
-extern struct fib_table *ip_fib_main_table;
+#define TABLE_LOCAL_INDEX       0
+#define TABLE_MAIN_INDEX        1
 
 static inline struct fib_table *fib_get_table(u32 id)
 {
-        if (id != RT_TABLE_LOCAL)
-                return ip_fib_main_table;
-        return ip_fib_local_table;
+        struct hlist_head *ptr;
+
+        ptr = id == RT_TABLE_LOCAL ?
+                &fib_table_hash[TABLE_LOCAL_INDEX] :
+                &fib_table_hash[TABLE_MAIN_INDEX];
+        return hlist_entry(ptr->first, struct fib_table, tb_hlist);
 }
 
 static inline struct fib_table *fib_new_table(u32 id)
@@ -173,16 +182,24 @@ static inline struct fib_table *fib_new_table(u32 id)
 
 static inline int fib_lookup(const struct flowi *flp, struct fib_result *res)
 {
-        if (ip_fib_local_table->tb_lookup(ip_fib_local_table, flp, res) &&
-            ip_fib_main_table->tb_lookup(ip_fib_main_table, flp, res))
-                return -ENETUNREACH;
-        return 0;
+        struct fib_table *table;
+
+        table = fib_get_table(RT_TABLE_LOCAL);
+        if (!table->tb_lookup(table, flp, res))
+                return 0;
+
+        table = fib_get_table(RT_TABLE_MAIN);
+        if (!table->tb_lookup(table, flp, res))
+                return 0;
+        return -ENETUNREACH;
 }
 
-static inline void fib_select_default(const struct flowi *flp, struct fib_result *res)
+static inline void fib_select_default(const struct flowi *flp,
+                                      struct fib_result *res)
 {
+        struct fib_table *table = fib_get_table(RT_TABLE_MAIN);
         if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
-                ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res);
+                table->tb_select_default(table, flp, res);
 }
 
 #else /* CONFIG_IP_MULTIPLE_TABLES */
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 0484cae02736..9ff1e6669ef2 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -50,39 +50,34 @@
 #define FFprint(a...) printk(KERN_DEBUG a)
 
 static struct sock *fibnl;
+struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
 
 #ifndef CONFIG_IP_MULTIPLE_TABLES
 
-struct fib_table *ip_fib_local_table;
-struct fib_table *ip_fib_main_table;
-
-#define FIB_TABLE_HASHSZ 1
-static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
-
 static int __net_init fib4_rules_init(struct net *net)
 {
-        ip_fib_local_table = fib_hash_init(RT_TABLE_LOCAL);
-        if (ip_fib_local_table == NULL)
+        struct fib_table *local_table, *main_table;
+
+        local_table = fib_hash_init(RT_TABLE_LOCAL);
+        if (local_table == NULL)
                 return -ENOMEM;
 
-        ip_fib_main_table  = fib_hash_init(RT_TABLE_MAIN);
-        if (ip_fib_main_table == NULL)
+        main_table  = fib_hash_init(RT_TABLE_MAIN);
+        if (main_table == NULL)
                 goto fail;
 
-        hlist_add_head_rcu(&ip_fib_local_table->tb_hlist, &fib_table_hash[0]);
-        hlist_add_head_rcu(&ip_fib_main_table->tb_hlist, &fib_table_hash[0]);
+        hlist_add_head_rcu(&local_table->tb_hlist,
+                                &fib_table_hash[TABLE_LOCAL_INDEX]);
+        hlist_add_head_rcu(&main_table->tb_hlist,
+                                &fib_table_hash[TABLE_MAIN_INDEX]);
         return 0;
 
 fail:
-        kfree(ip_fib_local_table);
-        ip_fib_local_table = NULL;
+        kfree(local_table);
         return -ENOMEM;
 }
 #else
 
-#define FIB_TABLE_HASHSZ 256
-static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
-
 struct fib_table *fib_new_table(u32 id)
 {
         struct fib_table *tb;