Commit 1f4c3dce authored by James Chapman's avatar James Chapman Committed by David S. Miller
Browse files

l2tp: use get_next APIs for management requests and procfs/debugfs 



l2tp netlink and procfs/debugfs iterate over tunnel and session lists
to obtain data. They currently use very inefficient get_nth functions
to do so. Replace these with get_next.

For netlink, use nl cb->ctx[] for passing state instead of the
obsolete cb->args[].

l2tp_tunnel_get_nth and l2tp_session_get_nth are no longer used so
they can be removed.

Signed-off-by: default avatarJames Chapman <jchapman@katalix.com>
Signed-off-by: default avatarTom Parkin <tparkin@katalix.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent aa92c1ce

net/l2tp/l2tp_core.c

+0 −40
Original line number Diff line number Diff line
@@ -241,27 +241,6 @@ struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id) 
}

EXPORT_SYMBOL_GPL(l2tp_tunnel_get);



struct l2tp_tunnel *l2tp_tunnel_get_nth(const struct net *net, int nth)

{

	struct l2tp_net *pn = l2tp_pernet(net);

	unsigned long tunnel_id, tmp;

	struct l2tp_tunnel *tunnel;

	int count = 0;



	rcu_read_lock_bh();

	idr_for_each_entry_ul(&pn->l2tp_tunnel_idr, tunnel, tmp, tunnel_id) {

		if (tunnel && ++count > nth &&

		    refcount_inc_not_zero(&tunnel->ref_count)) {

			rcu_read_unlock_bh();

			return tunnel;

		}

	}

	rcu_read_unlock_bh();



	return NULL;

}

EXPORT_SYMBOL_GPL(l2tp_tunnel_get_nth);



struct l2tp_tunnel *l2tp_tunnel_get_next(const struct net *net, unsigned long *key)

{

	struct l2tp_net *pn = l2tp_pernet(net);
@@ -355,25 +334,6 @@ struct l2tp_session *l2tp_session_get(const struct net *net, struct sock *sk, in 
}

EXPORT_SYMBOL_GPL(l2tp_session_get);



struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth)

{

	struct l2tp_session *session;

	int count = 0;



	rcu_read_lock_bh();

	list_for_each_entry_rcu(session, &tunnel->session_list, list) {

		if (++count > nth) {

			l2tp_session_inc_refcount(session);

			rcu_read_unlock_bh();

			return session;

		}

	}

	rcu_read_unlock_bh();



	return NULL;

}

EXPORT_SYMBOL_GPL(l2tp_session_get_nth);



static struct l2tp_session *l2tp_v2_session_get_next(const struct net *net,

						     u16 tid,

						     unsigned long *key)

net/l2tp/l2tp_core.h

+0 −2
Original line number Diff line number Diff line
@@ -219,14 +219,12 @@ void l2tp_session_dec_refcount(struct l2tp_session *session); 
 * the caller must ensure that the reference is dropped appropriately.

 */

struct l2tp_tunnel *l2tp_tunnel_get(const struct net *net, u32 tunnel_id);

struct l2tp_tunnel *l2tp_tunnel_get_nth(const struct net *net, int nth);

struct l2tp_tunnel *l2tp_tunnel_get_next(const struct net *net, unsigned long *key);



struct l2tp_session *l2tp_v3_session_get(const struct net *net, struct sock *sk, u32 session_id);

struct l2tp_session *l2tp_v2_session_get(const struct net *net, u16 tunnel_id, u16 session_id);

struct l2tp_session *l2tp_session_get(const struct net *net, struct sock *sk, int pver,

				      u32 tunnel_id, u32 session_id);

struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth);

struct l2tp_session *l2tp_session_get_next(const struct net *net, struct sock *sk, int pver,

					   u32 tunnel_id, unsigned long *key);

struct l2tp_session *l2tp_session_get_by_ifname(const struct net *net,

net/l2tp/l2tp_debugfs.c

+9 −7
Original line number Diff line number Diff line
@@ -34,8 +34,8 @@ static struct dentry *rootdir; 
struct l2tp_dfs_seq_data {

	struct net	*net;

	netns_tracker	ns_tracker;

	int tunnel_idx;			/* current tunnel */

	int session_idx;		/* index of session within current tunnel */

	unsigned long tkey;		/* lookup key of current tunnel */

	unsigned long skey;		/* lookup key of current session */

	struct l2tp_tunnel *tunnel;

	struct l2tp_session *session;	/* NULL means get next tunnel */

};
@@ -46,8 +46,8 @@ static void l2tp_dfs_next_tunnel(struct l2tp_dfs_seq_data *pd) 
	if (pd->tunnel)

		l2tp_tunnel_dec_refcount(pd->tunnel);



	pd->tunnel = l2tp_tunnel_get_nth(pd->net, pd->tunnel_idx);

	pd->tunnel_idx++;

	pd->tunnel = l2tp_tunnel_get_next(pd->net, &pd->tkey);

	pd->tkey++;

}



static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd)
@@ -56,11 +56,13 @@ static void l2tp_dfs_next_session(struct l2tp_dfs_seq_data *pd) 
	if (pd->session)

		l2tp_session_dec_refcount(pd->session);



	pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);

	pd->session_idx++;

	pd->session = l2tp_session_get_next(pd->net, pd->tunnel->sock,

					    pd->tunnel->version,

					    pd->tunnel->tunnel_id, &pd->skey);

	pd->skey++;



	if (!pd->session) {

		pd->session_idx = 0;

		pd->skey = 0;

		l2tp_dfs_next_tunnel(pd);

	}

}

net/l2tp/l2tp_netlink.c

+21 −13
Original line number Diff line number Diff line
@@ -491,14 +491,20 @@ static int l2tp_nl_cmd_tunnel_get(struct sk_buff *skb, struct genl_info *info) 
	return ret;

}



struct l2tp_nl_cb_data {

	unsigned long tkey;

	unsigned long skey;

};



static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback *cb)

{

	int ti = cb->args[0];

	struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];

	unsigned long key = cbd->tkey;

	struct l2tp_tunnel *tunnel;

	struct net *net = sock_net(skb->sk);



	for (;;) {

		tunnel = l2tp_tunnel_get_nth(net, ti);

		tunnel = l2tp_tunnel_get_next(net, &key);

		if (!tunnel)

			goto out;
@@ -510,11 +516,11 @@ static int l2tp_nl_cmd_tunnel_dump(struct sk_buff *skb, struct netlink_callback 
		}

		l2tp_tunnel_dec_refcount(tunnel);



		ti++;

		key++;

	}



out:

	cb->args[0] = ti;

	cbd->tkey = key;



	return skb->len;

}
@@ -832,25 +838,27 @@ static int l2tp_nl_cmd_session_get(struct sk_buff *skb, struct genl_info *info) 


static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback *cb)

{

	struct l2tp_nl_cb_data *cbd = (void *)&cb->ctx[0];

	struct net *net = sock_net(skb->sk);

	struct l2tp_session *session;

	struct l2tp_tunnel *tunnel = NULL;

	int ti = cb->args[0];

	int si = cb->args[1];

	unsigned long tkey = cbd->tkey;

	unsigned long skey = cbd->skey;



	for (;;) {

		if (!tunnel) {

			tunnel = l2tp_tunnel_get_nth(net, ti);

			tunnel = l2tp_tunnel_get_next(net, &tkey);

			if (!tunnel)

				goto out;

		}



		session = l2tp_session_get_nth(tunnel, si);

		session = l2tp_session_get_next(net, tunnel->sock, tunnel->version,

						tunnel->tunnel_id, &skey);

		if (!session) {

			ti++;

			tkey++;

			l2tp_tunnel_dec_refcount(tunnel);

			tunnel = NULL;

			si = 0;

			skey = 0;

			continue;

		}
@@ -863,12 +871,12 @@ static int l2tp_nl_cmd_session_dump(struct sk_buff *skb, struct netlink_callback 
		}

		l2tp_session_dec_refcount(session);



		si++;

		skey++;

	}



out:

	cb->args[0] = ti;

	cb->args[1] = si;

	cbd->tkey = tkey;

	cbd->skey = skey;



	return skb->len;

}

net/l2tp/l2tp_ppp.c

+9 −7
Original line number Diff line number Diff line
@@ -1397,8 +1397,8 @@ static int pppol2tp_getsockopt(struct socket *sock, int level, int optname, 


struct pppol2tp_seq_data {

	struct seq_net_private p;

	int tunnel_idx;			/* current tunnel */

	int session_idx;		/* index of session within current tunnel */

	unsigned long tkey;		/* lookup key of current tunnel */

	unsigned long skey;		/* lookup key of current session */

	struct l2tp_tunnel *tunnel;

	struct l2tp_session *session;	/* NULL means get next tunnel */

};
@@ -1410,8 +1410,8 @@ static void pppol2tp_next_tunnel(struct net *net, struct pppol2tp_seq_data *pd) 
		l2tp_tunnel_dec_refcount(pd->tunnel);



	for (;;) {

		pd->tunnel = l2tp_tunnel_get_nth(net, pd->tunnel_idx);

		pd->tunnel_idx++;

		pd->tunnel = l2tp_tunnel_get_next(net, &pd->tkey);

		pd->tkey++;



		/* Only accept L2TPv2 tunnels */

		if (!pd->tunnel || pd->tunnel->version == 2)
@@ -1427,11 +1427,13 @@ static void pppol2tp_next_session(struct net *net, struct pppol2tp_seq_data *pd) 
	if (pd->session)

		l2tp_session_dec_refcount(pd->session);



	pd->session = l2tp_session_get_nth(pd->tunnel, pd->session_idx);

	pd->session_idx++;

	pd->session = l2tp_session_get_next(net, pd->tunnel->sock,

					    pd->tunnel->version,

					    pd->tunnel->tunnel_id, &pd->skey);

	pd->skey++;



	if (!pd->session) {

		pd->session_idx = 0;

		pd->skey = 0;

		pppol2tp_next_tunnel(net, pd);

	}

}