Commit 1b43af54 authored by Patrick McHardy's avatar Patrick McHardy Committed by David S. Miller
Browse files

[IPV6]: Increase number of possible routing tables to 2^32 



Increase number of possible routing tables to 2^32 by replacing iterations
over all possible table IDs by hash table walking.

Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1af5a8c4

include/net/ip6_route.h

+7 −0
Original line number Diff line number Diff line
@@ -137,6 +137,13 @@ extern int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *a 
extern int inet6_rtm_delroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);

extern int inet6_rtm_getroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg);



struct rt6_rtnl_dump_arg

{

	struct sk_buff *skb;

	struct netlink_callback *cb;

};



extern int rt6_dump_route(struct rt6_info *rt, void *p_arg);

extern void rt6_ifdown(struct net_device *dev);

extern void rt6_mtu_change(struct net_device *dev, unsigned mtu);

net/ipv6/ip6_fib.c

+151 −20
Original line number Diff line number Diff line
@@ -158,7 +158,26 @@ static struct fib6_table fib6_main_tbl = { 
};



#ifdef CONFIG_IPV6_MULTIPLE_TABLES

#define FIB_TABLE_HASHSZ 256

#else

#define FIB_TABLE_HASHSZ 1

#endif

static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];



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]);

}



#ifdef CONFIG_IPV6_MULTIPLE_TABLES

static struct fib6_table fib6_local_tbl = {

	.tb6_id		= RT6_TABLE_LOCAL,

	.tb6_lock	= RW_LOCK_UNLOCKED,
@@ -168,9 +187,6 @@ static struct fib6_table fib6_local_tbl = { 
	},

};



#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;
@@ -186,19 +202,6 @@ static struct fib6_table *fib6_alloc_table(u32 id) 
	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;
@@ -263,10 +266,135 @@ struct dst_entry *fib6_rule_lookup(struct flowi *fl, int flags, 


static void __init fib6_tables_init(void)

{

	fib6_link_table(&fib6_main_tbl);

}



#endif



static int fib6_dump_node(struct fib6_walker_t *w)

{

	int res;

	struct rt6_info *rt;



	for (rt = w->leaf; rt; rt = rt->u.next) {

		res = rt6_dump_route(rt, w->args);

		if (res < 0) {

			/* Frame is full, suspend walking */

			w->leaf = rt;

			return 1;

		}

		BUG_TRAP(res!=0);

	}

	w->leaf = NULL;

	return 0;

}



static void fib6_dump_end(struct netlink_callback *cb)

{

	struct fib6_walker_t *w = (void*)cb->args[2];



	if (w) {

		cb->args[2] = 0;

		kfree(w);

	}

	cb->done = (void*)cb->args[3];

	cb->args[1] = 3;

}



static int fib6_dump_done(struct netlink_callback *cb)

{

	fib6_dump_end(cb);

	return cb->done ? cb->done(cb) : 0;

}



static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,

			   struct netlink_callback *cb)

{

	struct fib6_walker_t *w;

	int res;



	w = (void *)cb->args[2];

	w->root = &table->tb6_root;



	if (cb->args[4] == 0) {

		read_lock_bh(&table->tb6_lock);

		res = fib6_walk(w);

		read_unlock_bh(&table->tb6_lock);

		if (res > 0)

			cb->args[4] = 1;

	} else {

		read_lock_bh(&table->tb6_lock);

		res = fib6_walk_continue(w);

		read_unlock_bh(&table->tb6_lock);

		if (res != 0) {

			if (res < 0)

				fib6_walker_unlink(w);

			goto end;

		}

		fib6_walker_unlink(w);

		cb->args[4] = 0;

	}

end:

	return res;

}



int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)

{

	unsigned int h, s_h;

	unsigned int e = 0, s_e;

	struct rt6_rtnl_dump_arg arg;

	struct fib6_walker_t *w;

	struct fib6_table *tb;

	struct hlist_node *node;

	int res = 0;



	s_h = cb->args[0];

	s_e = cb->args[1];



	w = (void *)cb->args[2];

	if (w == NULL) {

		/* New dump:

		 *

		 * 1. hook callback destructor.

		 */

		cb->args[3] = (long)cb->done;

		cb->done = fib6_dump_done;



		/*

		 * 2. allocate and initialize walker.

		 */

		w = kzalloc(sizeof(*w), GFP_ATOMIC);

		if (w == NULL)

			return -ENOMEM;

		w->func = fib6_dump_node;

		cb->args[2] = (long)w;

	}



	arg.skb = skb;

	arg.cb = cb;

	w->args = &arg;



	for (h = s_h; h < FIB_TABLE_HASHSZ; h++, s_e = 0) {

		e = 0;

		hlist_for_each_entry(tb, node, &fib_table_hash[h], tb6_hlist) {

			if (e < s_e)

				goto next;

			res = fib6_dump_table(tb, skb, cb);

			if (res != 0)

				goto out;

next:

			e++;

		}

	}

out:

	cb->args[1] = e;

	cb->args[0] = h;



	res = res < 0 ? res : skb->len;

	if (res <= 0)

		fib6_dump_end(cb);

	return res;

}



/*

 *	Routing Table
@@ -1187,17 +1315,20 @@ static void fib6_clean_tree(struct fib6_node *root, 
void fib6_clean_all(int (*func)(struct rt6_info *, void *arg),

		    int prune, void *arg)

{

	int i;

	struct fib6_table *table;

	struct hlist_node *node;

	unsigned int h;



	for (i = FIB6_TABLE_MIN; i <= FIB6_TABLE_MAX; i++) {

		table = fib6_get_table(i);

		if (table != NULL) {

	rcu_read_lock();

	for (h = 0; h < FIB_TABLE_HASHSZ; h++) {

		hlist_for_each_entry_rcu(table, node, &fib_table_hash[h],

					 tb6_hlist) {

			write_lock_bh(&table->tb6_lock);

			fib6_clean_tree(&table->tb6_root, func, prune, arg);

			write_unlock_bh(&table->tb6_lock);

		}

	}

	rcu_read_unlock();

}



static int fib6_prune_clone(struct rt6_info *rt, void *arg)

net/ipv6/route.c

+1 −127
Original line number Diff line number Diff line
@@ -1874,12 +1874,6 @@ int inet6_rtm_newroute(struct sk_buff *skb, struct nlmsghdr* nlh, void *arg) 
			     rtm_get_table(arg, r->rtm_table));

}



struct rt6_rtnl_dump_arg

{

	struct sk_buff *skb;

	struct netlink_callback *cb;

};



static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt,

			 struct in6_addr *dst, struct in6_addr *src,

			 int iif, int type, u32 pid, u32 seq,
@@ -1976,7 +1970,7 @@ static int rt6_fill_node(struct sk_buff *skb, struct rt6_info *rt, 
	return -1;

}



static int rt6_dump_route(struct rt6_info *rt, void *p_arg)

int rt6_dump_route(struct rt6_info *rt, void *p_arg)

{

	struct rt6_rtnl_dump_arg *arg = (struct rt6_rtnl_dump_arg *) p_arg;

	int prefix;
@@ -1992,126 +1986,6 @@ static int rt6_dump_route(struct rt6_info *rt, void *p_arg) 
		     prefix, NLM_F_MULTI);

}



static int fib6_dump_node(struct fib6_walker_t *w)

{

	int res;

	struct rt6_info *rt;



	for (rt = w->leaf; rt; rt = rt->u.next) {

		res = rt6_dump_route(rt, w->args);

		if (res < 0) {

			/* Frame is full, suspend walking */

			w->leaf = rt;

			return 1;

		}

		BUG_TRAP(res!=0);

	}

	w->leaf = NULL;

	return 0;

}



static void fib6_dump_end(struct netlink_callback *cb)

{

	struct fib6_walker_t *w = (void*)cb->args[0];



	if (w) {

		cb->args[0] = 0;

		kfree(w);

	}

	cb->done = (void*)cb->args[1];

	cb->args[1] = 0;

}



static int fib6_dump_done(struct netlink_callback *cb)

{

	fib6_dump_end(cb);

	return cb->done ? cb->done(cb) : 0;

}



int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)

{

	struct fib6_table *table;

	struct rt6_rtnl_dump_arg arg;

	struct fib6_walker_t *w;

	int i, res = 0;



	arg.skb = skb;

	arg.cb = cb;



	/*

	 * cb->args[0] = pointer to walker structure

	 * cb->args[1] = saved cb->done() pointer

	 * cb->args[2] = current table being dumped

	 */



	w = (void*)cb->args[0];

	if (w == NULL) {

		/* New dump:

		 * 

		 * 1. hook callback destructor.

		 */

		cb->args[1] = (long)cb->done;

		cb->done = fib6_dump_done;



		/*

		 * 2. allocate and initialize walker.

		 */

		w = kzalloc(sizeof(*w), GFP_ATOMIC);

		if (w == NULL)

			return -ENOMEM;

		w->func = fib6_dump_node;

		w->args = &arg;

		cb->args[0] = (long)w;

		cb->args[2] = FIB6_TABLE_MIN;

	} else {

		w->args = &arg;

		i = cb->args[2];

		if (i > FIB6_TABLE_MAX)

			goto end;



		table = fib6_get_table(i);

		if (table != NULL) {

			read_lock_bh(&table->tb6_lock);

			w->root = &table->tb6_root;

			res = fib6_walk_continue(w);

			read_unlock_bh(&table->tb6_lock);

			if (res != 0) {

				if (res < 0)

					fib6_walker_unlink(w);

				goto end;

			}

		}



		fib6_walker_unlink(w);

		cb->args[2] = ++i;

	}



	for (i = cb->args[2]; i <= FIB6_TABLE_MAX; i++) {

		table = fib6_get_table(i);

		if (table == NULL)

			continue;



		read_lock_bh(&table->tb6_lock);

		w->root = &table->tb6_root;

		res = fib6_walk(w);

		read_unlock_bh(&table->tb6_lock);

		if (res)

			break;

	}

end:

	cb->args[2] = i;



	res = res < 0 ? res : skb->len;

	/* res < 0 is an error. (really, impossible)

	   res == 0 means that dump is complete, but skb still can contain data.

	   res > 0 dump is not complete, but frame is full.

	 */

	/* Destroy walker, if dump of this table is complete. */

	if (res <= 0)

		fib6_dump_end(cb);

	return res;

}



int inet6_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)

{

	struct rtattr **rta = arg;