[IPV6]: Multiple Routing Tables
Adds the framework to support multiple IPv6 routing tables.
Currently all automatically generated routes are put into the
same table. This could be changed at a later point after
considering the produced locking overhead.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 7642212..fcd7da8 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -26,6 +26,7 @@
#include <linux/netdevice.h>
#include <linux/in6.h>
#include <linux/init.h>
+#include <linux/list.h>
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
@@ -147,6 +148,126 @@
dst_free(&rt->u.dst);
}
+static struct fib6_table fib6_main_tbl = {
+ .tb6_id = RT6_TABLE_MAIN,
+ .tb6_lock = RW_LOCK_UNLOCKED,
+ .tb6_root = {
+ .leaf = &ip6_null_entry,
+ .fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO,
+ },
+};
+
+#ifdef CONFIG_IPV6_MULTIPLE_TABLES
+
+#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;
+
+ table = kzalloc(sizeof(*table), GFP_ATOMIC);
+ if (table != NULL) {
+ table->tb6_id = id;
+ table->tb6_lock = RW_LOCK_UNLOCKED;
+ table->tb6_root.leaf = &ip6_null_entry;
+ table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
+ }
+
+ 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;
+
+ if (id == 0)
+ id = RT6_TABLE_MAIN;
+ tb = fib6_get_table(id);
+ if (tb)
+ return tb;
+
+ tb = fib6_alloc_table(id);
+ if (tb != NULL)
+ fib6_link_table(tb);
+
+ return tb;
+}
+
+struct fib6_table *fib6_get_table(u32 id)
+{
+ struct fib6_table *tb;
+ struct hlist_node *node;
+ unsigned int h;
+
+ if (id == 0)
+ id = RT6_TABLE_MAIN;
+ h = id & (FIB_TABLE_HASHSZ - 1);
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(tb, node, &fib_table_hash[h], tb6_hlist) {
+ if (tb->tb6_id == id) {
+ rcu_read_unlock();
+ return tb;
+ }
+ }
+ rcu_read_unlock();
+
+ return NULL;
+}
+
+struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags,
+ pol_lookup_t lookup)
+{
+ /*
+ * TODO: Add rule lookup
+ */
+ struct fib6_table *table = fib6_get_table(RT6_TABLE_MAIN);
+
+ return (struct dst_entry *) lookup(table, fl, flags);
+}
+
+static void __init fib6_tables_init(void)
+{
+ fib6_link_table(&fib6_main_tbl);
+}
+
+#else
+
+struct fib6_table *fib6_new_table(u32 id)
+{
+ return fib6_get_table(id);
+}
+
+struct fib6_table *fib6_get_table(u32 id)
+{
+ return &fib6_main_tbl;
+}
+
+struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags,
+ pol_lookup_t lookup)
+{
+ return (struct dst_entry *) lookup(&fib6_main_tbl, fl, flags);
+}
+
+static void __init fib6_tables_init(void)
+{
+}
+
+#endif
+
/*
* Routing Table
@@ -1064,6 +1185,22 @@
fib6_walk(&c.w);
}
+void fib6_clean_all(int (*func)(struct rt6_info *, void *arg),
+ int prune, void *arg)
+{
+ int i;
+ struct fib6_table *table;
+
+ for (i = FIB6_TABLE_MIN; i <= FIB6_TABLE_MAX; i++) {
+ table = fib6_get_table(i);
+ if (table != NULL) {
+ write_lock_bh(&table->tb6_lock);
+ fib6_clean_tree(&table->tb6_root, func, prune, arg);
+ write_unlock_bh(&table->tb6_lock);
+ }
+ }
+}
+
static int fib6_prune_clone(struct rt6_info *rt, void *arg)
{
if (rt->rt6i_flags & RTF_CACHE) {
@@ -1142,11 +1279,8 @@
}
gc_args.more = 0;
-
- write_lock_bh(&rt6_lock);
ndisc_dst_gc(&gc_args.more);
- fib6_clean_tree(&ip6_routing_table, fib6_age, 0, NULL);
- write_unlock_bh(&rt6_lock);
+ fib6_clean_all(fib6_age, 0, NULL);
if (gc_args.more)
mod_timer(&ip6_fib_timer, jiffies + ip6_rt_gc_interval);
@@ -1165,6 +1299,8 @@
NULL, NULL);
if (!fib6_node_kmem)
panic("cannot create fib6_nodes cache");
+
+ fib6_tables_init();
}
void fib6_gc_cleanup(void)