diff options
Diffstat (limited to 'net/mptcp/protocol.c')
-rw-r--r-- | net/mptcp/protocol.c | 117 |
1 files changed, 50 insertions, 67 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 3e8cfaed00b5..c5f64fb0474d 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -808,47 +808,38 @@ void mptcp_data_ready(struct sock *sk, struct sock *ssk) mptcp_data_unlock(sk); } -static bool mptcp_do_flush_join_list(struct mptcp_sock *msk) +static bool __mptcp_finish_join(struct mptcp_sock *msk, struct sock *ssk) { - struct mptcp_subflow_context *subflow; - bool ret = false; + struct sock *sk = (struct sock *)msk; - if (likely(list_empty(&msk->join_list))) + if (sk->sk_state != TCP_ESTABLISHED) return false; - spin_lock_bh(&msk->join_list_lock); - list_for_each_entry(subflow, &msk->join_list, node) { - u32 sseq = READ_ONCE(subflow->setsockopt_seq); - - mptcp_propagate_sndbuf((struct sock *)msk, mptcp_subflow_tcp_sock(subflow)); - if (READ_ONCE(msk->setsockopt_seq) != sseq) - ret = true; - } - list_splice_tail_init(&msk->join_list, &msk->conn_list); - spin_unlock_bh(&msk->join_list_lock); - - return ret; -} - -void __mptcp_flush_join_list(struct mptcp_sock *msk) -{ - if (likely(!mptcp_do_flush_join_list(msk))) - return; + /* attach to msk socket only after we are sure we will deal with it + * at close time + */ + if (sk->sk_socket && !ssk->sk_socket) + mptcp_sock_graft(ssk, sk->sk_socket); - if (!test_and_set_bit(MPTCP_WORK_SYNC_SETSOCKOPT, &msk->flags)) - mptcp_schedule_work((struct sock *)msk); + mptcp_propagate_sndbuf((struct sock *)msk, ssk); + mptcp_sockopt_sync_locked(msk, ssk); + return true; } -static void mptcp_flush_join_list(struct mptcp_sock *msk) +static void __mptcp_flush_join_list(struct sock *sk) { - bool sync_needed = test_and_clear_bit(MPTCP_WORK_SYNC_SETSOCKOPT, &msk->flags); - - might_sleep(); + struct mptcp_subflow_context *tmp, *subflow; + struct mptcp_sock *msk = mptcp_sk(sk); - if (!mptcp_do_flush_join_list(msk) && !sync_needed) - return; + list_for_each_entry_safe(subflow, tmp, &msk->join_list, node) { + struct sock *ssk = mptcp_subflow_tcp_sock(subflow); + bool slow = lock_sock_fast(ssk); - mptcp_sockopt_sync_all(msk); + list_move_tail(&subflow->node, &msk->conn_list); + if (!__mptcp_finish_join(msk, ssk)) + mptcp_subflow_reset(ssk); + unlock_sock_fast(ssk, slow); + } } static bool mptcp_timer_pending(struct sock *sk) @@ -1549,7 +1540,6 @@ void __mptcp_push_pending(struct sock *sk, unsigned int flags) int ret = 0; prev_ssk = ssk; - __mptcp_flush_join_list(msk); ssk = mptcp_subflow_get_send(msk); /* First check. If the ssk has changed since @@ -1954,7 +1944,6 @@ static bool __mptcp_move_skbs(struct mptcp_sock *msk) unsigned int moved = 0; bool ret, done; - mptcp_flush_join_list(msk); do { struct sock *ssk = mptcp_subflow_recv_lookup(msk); bool slowpath; @@ -2490,7 +2479,6 @@ static void mptcp_worker(struct work_struct *work) goto unlock; mptcp_check_data_fin_ack(sk); - mptcp_flush_join_list(msk); mptcp_check_fastclose(msk); @@ -2528,8 +2516,6 @@ static int __mptcp_init_sock(struct sock *sk) { struct mptcp_sock *msk = mptcp_sk(sk); - spin_lock_init(&msk->join_list_lock); - INIT_LIST_HEAD(&msk->conn_list); INIT_LIST_HEAD(&msk->join_list); INIT_LIST_HEAD(&msk->rtx_queue); @@ -2703,7 +2689,6 @@ static void __mptcp_check_send_data_fin(struct sock *sk) } } - mptcp_flush_join_list(msk); mptcp_for_each_subflow(msk, subflow) { struct sock *tcp_sk = mptcp_subflow_tcp_sock(subflow); @@ -2736,12 +2721,7 @@ static void __mptcp_destroy_sock(struct sock *sk) might_sleep(); - /* be sure to always acquire the join list lock, to sync vs - * mptcp_finish_join(). - */ - spin_lock_bh(&msk->join_list_lock); - list_splice_tail_init(&msk->join_list, &msk->conn_list); - spin_unlock_bh(&msk->join_list_lock); + /* join list will be eventually flushed (with rst) at sock lock release time*/ list_splice_init(&msk->conn_list, &conn_list); sk_stop_timer(sk, &msk->sk.icsk_retransmit_timer); @@ -2844,8 +2824,6 @@ static int mptcp_disconnect(struct sock *sk, int flags) struct mptcp_subflow_context *subflow; struct mptcp_sock *msk = mptcp_sk(sk); - mptcp_do_flush_join_list(msk); - inet_sk_state_store(sk, TCP_CLOSE); mptcp_for_each_subflow(msk, subflow) { @@ -3076,6 +3054,8 @@ static void mptcp_release_cb(struct sock *sk) flags |= BIT(MPTCP_PUSH_PENDING); if (test_and_clear_bit(MPTCP_RETRANSMIT, &mptcp_sk(sk)->flags)) flags |= BIT(MPTCP_RETRANSMIT); + if (test_and_clear_bit(MPTCP_FLUSH_JOIN_LIST, &mptcp_sk(sk)->flags)) + flags |= BIT(MPTCP_FLUSH_JOIN_LIST); if (!flags) break; @@ -3088,6 +3068,8 @@ static void mptcp_release_cb(struct sock *sk) */ spin_unlock_bh(&sk->sk_lock.slock); + if (flags & BIT(MPTCP_FLUSH_JOIN_LIST)) + __mptcp_flush_join_list(sk); if (flags & BIT(MPTCP_PUSH_PENDING)) __mptcp_push_pending(sk, 0); if (flags & BIT(MPTCP_RETRANSMIT)) @@ -3232,8 +3214,7 @@ bool mptcp_finish_join(struct sock *ssk) struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk); struct mptcp_sock *msk = mptcp_sk(subflow->conn); struct sock *parent = (void *)msk; - struct socket *parent_sock; - bool ret; + bool ret = true; pr_debug("msk=%p, subflow=%p", msk, subflow); @@ -3246,35 +3227,38 @@ bool mptcp_finish_join(struct sock *ssk) if (!msk->pm.server_side) goto out; - if (!mptcp_pm_allow_new_subflow(msk)) { - subflow->reset_reason = MPTCP_RST_EPROHIBIT; - return false; - } + if (!mptcp_pm_allow_new_subflow(msk)) + goto err_prohibited; - /* active connections are already on conn_list, and we can't acquire - * msk lock here. - * use the join list lock as synchronization point and double-check - * msk status to avoid racing with __mptcp_destroy_sock() + if (WARN_ON_ONCE(!list_empty(&subflow->node))) + goto err_prohibited; + + /* active connections are already on conn_list. + * If we can't acquire msk socket lock here, let the release callback + * handle it */ - spin_lock_bh(&msk->join_list_lock); - ret = inet_sk_state_load(parent) == TCP_ESTABLISHED; - if (ret && !WARN_ON_ONCE(!list_empty(&subflow->node))) { - list_add_tail(&subflow->node, &msk->join_list); + mptcp_data_lock(parent); + if (!sock_owned_by_user(parent)) { + ret = __mptcp_finish_join(msk, ssk); + if (ret) { + sock_hold(ssk); + list_add_tail(&subflow->node, &msk->conn_list); + } + } else { sock_hold(ssk); + list_add_tail(&subflow->node, &msk->join_list); + set_bit(MPTCP_FLUSH_JOIN_LIST, &msk->flags); } - spin_unlock_bh(&msk->join_list_lock); + mptcp_data_unlock(parent); + if (!ret) { +err_prohibited: subflow->reset_reason = MPTCP_RST_EPROHIBIT; return false; } - /* attach to msk socket only after we are sure he will deal with us - * at close time - */ - parent_sock = READ_ONCE(parent->sk_socket); - if (parent_sock && !ssk->sk_socket) - mptcp_sock_graft(ssk, parent_sock); subflow->map_seq = READ_ONCE(msk->ack_seq); + out: mptcp_event(MPTCP_EVENT_SUB_ESTABLISHED, msk, ssk, GFP_ATOMIC); return true; @@ -3539,7 +3523,6 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock, /* set ssk->sk_socket of accept()ed flows to mptcp socket. * This is needed so NOSPACE flag can be set from tcp stack. */ - mptcp_flush_join_list(msk); mptcp_for_each_subflow(msk, subflow) { struct sock *ssk = mptcp_subflow_tcp_sock(subflow); |