diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c index 93271a2632b8..7499c51b1850 100644 --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -250,15 +250,15 @@ struct l2tp_session *l2tp_tunnel_get_session(struct l2tp_tunnel *tunnel, session_list = l2tp_session_id_hash(tunnel, session_id); - read_lock_bh(&tunnel->hlist_lock); - hlist_for_each_entry(session, session_list, hlist) + rcu_read_lock_bh(); + hlist_for_each_entry_rcu(session, session_list, hlist) if (session->session_id == session_id) { l2tp_session_inc_refcount(session); - read_unlock_bh(&tunnel->hlist_lock); + rcu_read_unlock_bh(); return session; } - read_unlock_bh(&tunnel->hlist_lock); + rcu_read_unlock_bh(); return NULL; } @@ -291,18 +291,18 @@ struct l2tp_session *l2tp_session_get_nth(struct l2tp_tunnel *tunnel, int nth) struct l2tp_session *session; int count = 0; - read_lock_bh(&tunnel->hlist_lock); + rcu_read_lock_bh(); for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { - hlist_for_each_entry(session, &tunnel->session_hlist[hash], hlist) { + hlist_for_each_entry_rcu(session, &tunnel->session_hlist[hash], hlist) { if (++count > nth) { l2tp_session_inc_refcount(session); - read_unlock_bh(&tunnel->hlist_lock); + rcu_read_unlock_bh(); return session; } } } - read_unlock_bh(&tunnel->hlist_lock); + rcu_read_unlock_bh(); return NULL; } @@ -347,7 +347,7 @@ int l2tp_session_register(struct l2tp_session *session, head = l2tp_session_id_hash(tunnel, session->session_id); - write_lock_bh(&tunnel->hlist_lock); + spin_lock_bh(&tunnel->hlist_lock); if (!tunnel->acpt_newsess) { err = -ENODEV; goto err_tlock; @@ -384,8 +384,8 @@ int l2tp_session_register(struct l2tp_session *session, l2tp_tunnel_inc_refcount(tunnel); } - hlist_add_head(&session->hlist, head); - write_unlock_bh(&tunnel->hlist_lock); + hlist_add_head_rcu(&session->hlist, head); + spin_unlock_bh(&tunnel->hlist_lock); trace_register_session(session); @@ -394,7 +394,7 @@ int l2tp_session_register(struct l2tp_session *session, err_tlock_pnlock: spin_unlock_bh(&pn->l2tp_session_hlist_lock); err_tlock: - write_unlock_bh(&tunnel->hlist_lock); + spin_unlock_bh(&tunnel->hlist_lock); return err; } @@ -1170,9 +1170,9 @@ static void l2tp_session_unhash(struct l2tp_session *session) /* Remove the session from core hashes */ if (tunnel) { /* Remove from the per-tunnel hash */ - write_lock_bh(&tunnel->hlist_lock); - hlist_del_init(&session->hlist); - write_unlock_bh(&tunnel->hlist_lock); + spin_lock_bh(&tunnel->hlist_lock); + hlist_del_init_rcu(&session->hlist); + spin_unlock_bh(&tunnel->hlist_lock); /* For L2TPv3 we have a per-net hash: remove from there, too */ if (tunnel->version != L2TP_HDR_VER_2) { @@ -1181,8 +1181,9 @@ static void l2tp_session_unhash(struct l2tp_session *session) spin_lock_bh(&pn->l2tp_session_hlist_lock); hlist_del_init_rcu(&session->global_hlist); spin_unlock_bh(&pn->l2tp_session_hlist_lock); - synchronize_rcu(); } + + synchronize_rcu(); } } @@ -1190,22 +1191,19 @@ static void l2tp_session_unhash(struct l2tp_session *session) */ static void l2tp_tunnel_closeall(struct l2tp_tunnel *tunnel) { - int hash; - struct hlist_node *walk; - struct hlist_node *tmp; struct l2tp_session *session; + int hash; - write_lock_bh(&tunnel->hlist_lock); + spin_lock_bh(&tunnel->hlist_lock); tunnel->acpt_newsess = false; for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { again: - hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { - session = hlist_entry(walk, struct l2tp_session, hlist); - hlist_del_init(&session->hlist); + hlist_for_each_entry_rcu(session, &tunnel->session_hlist[hash], hlist) { + hlist_del_init_rcu(&session->hlist); - write_unlock_bh(&tunnel->hlist_lock); + spin_unlock_bh(&tunnel->hlist_lock); l2tp_session_delete(session); - write_lock_bh(&tunnel->hlist_lock); + spin_lock_bh(&tunnel->hlist_lock); /* Now restart from the beginning of this hash * chain. We always remove a session from the @@ -1215,7 +1213,7 @@ again: goto again; } } - write_unlock_bh(&tunnel->hlist_lock); + spin_unlock_bh(&tunnel->hlist_lock); } /* Tunnel socket destroy hook for UDP encapsulation */ @@ -1408,7 +1406,7 @@ int l2tp_tunnel_create(int fd, int version, u32 tunnel_id, u32 peer_tunnel_id, tunnel->magic = L2TP_TUNNEL_MAGIC; sprintf(&tunnel->name[0], "tunl %u", tunnel_id); - rwlock_init(&tunnel->hlist_lock); + spin_lock_init(&tunnel->hlist_lock); tunnel->acpt_newsess = true; tunnel->encap = encap; diff --git a/net/l2tp/l2tp_core.h b/net/l2tp/l2tp_core.h index 98ea98eb9567..a88e070b431d 100644 --- a/net/l2tp/l2tp_core.h +++ b/net/l2tp/l2tp_core.h @@ -160,7 +160,7 @@ struct l2tp_tunnel { unsigned long dead; struct rcu_head rcu; - rwlock_t hlist_lock; /* protect session_hlist */ + spinlock_t hlist_lock; /* write-protection for session_hlist */ bool acpt_newsess; /* indicates whether this tunnel accepts * new sessions. Protected by hlist_lock. */ diff --git a/net/l2tp/l2tp_debugfs.c b/net/l2tp/l2tp_debugfs.c index bca75bef8282..acf6e1343b88 100644 --- a/net/l2tp/l2tp_debugfs.c +++ b/net/l2tp/l2tp_debugfs.c @@ -120,24 +120,21 @@ static void l2tp_dfs_seq_stop(struct seq_file *p, void *v) static void l2tp_dfs_seq_tunnel_show(struct seq_file *m, void *v) { struct l2tp_tunnel *tunnel = v; + struct l2tp_session *session; int session_count = 0; int hash; - struct hlist_node *walk; - struct hlist_node *tmp; - read_lock_bh(&tunnel->hlist_lock); + rcu_read_lock_bh(); for (hash = 0; hash < L2TP_HASH_SIZE; hash++) { - hlist_for_each_safe(walk, tmp, &tunnel->session_hlist[hash]) { - struct l2tp_session *session; - - session = hlist_entry(walk, struct l2tp_session, hlist); + hlist_for_each_entry_rcu(session, &tunnel->session_hlist[hash], hlist) { + /* Session ID of zero is a dummy/reserved value used by pppol2tp */ if (session->session_id == 0) continue; session_count++; } } - read_unlock_bh(&tunnel->hlist_lock); + rcu_read_unlock_bh(); seq_printf(m, "\nTUNNEL %u peer %u", tunnel->tunnel_id, tunnel->peer_tunnel_id); if (tunnel->sock) {