diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index a21f8ed263436..7036e30c449fe 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -863,9 +863,8 @@ void mptcp_data_ready(struct sock *sk, struct sock *ssk)
/* Wake-up the reader only for in-sequence data */
mptcp_data_lock(sk);
- if (move_skbs_to_msk(msk, ssk))
+ if (move_skbs_to_msk(msk, ssk) && mptcp_epollin_ready(sk))
sk->sk_data_ready(sk);
-
mptcp_data_unlock(sk);
}
@@ -1922,6 +1921,7 @@ static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk,
if (!(flags & MSG_PEEK)) {
MPTCP_SKB_CB(skb)->offset += count;
MPTCP_SKB_CB(skb)->map_seq += count;
+ msk->bytes_consumed += count;
}
break;
}
@@ -1932,6 +1932,7 @@ static int __mptcp_recvmsg_mskq(struct mptcp_sock *msk,
WRITE_ONCE(msk->rmem_released, msk->rmem_released + skb->truesize);
__skb_unlink(skb, &msk->receive_queue);
__kfree_skb(skb);
+ msk->bytes_consumed += count;
}
if (copied >= len)
@@ -2755,6 +2756,7 @@ static void __mptcp_init_sock(struct sock *sk)
msk->rmem_fwd_alloc = 0;
WRITE_ONCE(msk->rmem_released, 0);
msk->timer_ival = TCP_RTO_MIN;
+ msk->scaling_ratio = TCP_DEFAULT_SCALING_RATIO;
WRITE_ONCE(msk->first, NULL);
inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss;
@@ -2964,16 +2966,9 @@ void __mptcp_unaccepted_force_close(struct sock *sk)
__mptcp_destroy_sock(sk);
}
-static __poll_t mptcp_check_readable(struct mptcp_sock *msk)
+static __poll_t mptcp_check_readable(struct sock *sk)
{
- /* Concurrent splices from sk_receive_queue into receive_queue will
- * always show at least one non-empty queue when checked in this order.
- */
- if (skb_queue_empty_lockless(&((struct sock *)msk)->sk_receive_queue) &&
- skb_queue_empty_lockless(&msk->receive_queue))
- return 0;
-
- return EPOLLIN | EPOLLRDNORM;
+ return mptcp_epollin_ready(sk) ? EPOLLIN | EPOLLRDNORM : 0;
}
static void mptcp_check_listen_stop(struct sock *sk)
@@ -3011,7 +3006,7 @@ bool __mptcp_close(struct sock *sk, long timeout)
goto cleanup;
}
- if (mptcp_check_readable(msk) || timeout < 0) {
+ if (mptcp_data_avail(msk) || timeout < 0) {
/* If the msk has read data, or the caller explicitly ask it,
* do the MPTCP equivalent of TCP reset, aka MPTCP fastclose
*/
@@ -3138,6 +3133,7 @@ static int mptcp_disconnect(struct sock *sk, int flags)
msk->snd_data_fin_enable = false;
msk->rcv_fastclose = false;
msk->use_64bit_ack = false;
+ msk->bytes_consumed = 0;
WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk)));
mptcp_pm_data_reset(msk);
mptcp_ca_reset(sk);
@@ -3909,7 +3905,7 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock,
mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
if (state != TCP_SYN_SENT && state != TCP_SYN_RECV) {
- mask |= mptcp_check_readable(msk);
+ mask |= mptcp_check_readable(sk);
if (shutdown & SEND_SHUTDOWN)
mask |= EPOLLOUT | EPOLLWRNORM;
else
@@ -3947,6 +3943,7 @@ static const struct proto_ops mptcp_stream_ops = {
.sendmsg = inet_sendmsg,
.recvmsg = inet_recvmsg,
.mmap = sock_no_mmap,
+ .set_rcvlowat = mptcp_set_rcvlowat,
};
static struct inet_protosw mptcp_protosw = {
@@ -4048,6 +4045,7 @@ static const struct proto_ops mptcp_v6_stream_ops = {
#ifdef CONFIG_COMPAT
.compat_ioctl = inet6_compat_ioctl,
#endif
+ .set_rcvlowat = mptcp_set_rcvlowat,
};
static struct proto mptcp_v6_prot;
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index 6df62a8a73bcb..5971d34a3dee6 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -269,6 +269,7 @@ struct mptcp_sock {
atomic64_t rcv_wnd_sent;
u64 rcv_data_fin_seq;
u64 bytes_retrans;
+ u64 bytes_consumed;
int rmem_fwd_alloc;
int snd_burst;
int old_wspace;
@@ -659,6 +660,24 @@ struct sock *mptcp_subflow_get_retrans(struct mptcp_sock *msk);
int mptcp_sched_get_send(struct mptcp_sock *msk);
int mptcp_sched_get_retrans(struct mptcp_sock *msk);
+static inline u64 mptcp_data_avail(const struct mptcp_sock *msk)
+{
+ return READ_ONCE(msk->bytes_received) - READ_ONCE(msk->bytes_consumed);
+}
+
+static inline bool mptcp_epollin_ready(const struct sock *sk)
+{
+ /* mptcp doesn't have to deal with small skbs in the receive queue,
+ * at it can always coalesce them
+ */
+ return (mptcp_data_avail(mptcp_sk(sk)) >= sk->sk_rcvlowat) ||
+ (mem_cgroup_sockets_enabled && sk->sk_memcg &&
+ mem_cgroup_under_socket_pressure(sk->sk_memcg)) ||
+ READ_ONCE(tcp_memory_pressure);
+}
+
+int mptcp_set_rcvlowat(struct sock *sk, int val);
+
static inline bool __tcp_can_send(const struct sock *ssk)
{
/* only send if our side has not closed yet */
@@ -733,6 +752,7 @@ static inline bool mptcp_is_fully_established(struct sock *sk)
return inet_sk_state_load(sk) == TCP_ESTABLISHED &&
READ_ONCE(mptcp_sk(sk)->fully_established);
}
+
void mptcp_rcv_space_init(struct mptcp_sock *msk, const struct sock *ssk);
void mptcp_data_ready(struct sock *sk, struct sock *ssk);
bool mptcp_finish_join(struct sock *sk);
diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index 59bd5e114392a..d15891e23f451 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -1472,9 +1472,51 @@ void mptcp_sockopt_sync_locked(struct mptcp_sock *msk, struct sock *ssk)
msk_owned_by_me(msk);
+ ssk->sk_rcvlowat = 0;
+
if (READ_ONCE(subflow->setsockopt_seq) != msk->setsockopt_seq) {
sync_socket_options(msk, ssk);
subflow->setsockopt_seq = msk->setsockopt_seq;
}
}
+
+/* unfortunately this is different enough from the tcp version so
+ * that we can't factor it out
+ */
+int mptcp_set_rcvlowat(struct sock *sk, int val)
+{
+ struct mptcp_subflow_context *subflow;
+ int space, cap;
+
+ if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
+ cap = sk->sk_rcvbuf >> 1;
+ else
+ cap = READ_ONCE(sock_net(sk)->ipv4.sysctl_tcp_rmem[2]) >> 1;
+ val = min(val, cap);
+ WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
+
+ /* Check if we need to signal EPOLLIN right now */
+ if (mptcp_epollin_ready(sk))
+ sk->sk_data_ready(sk);
+
+ if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
+ return 0;
+
+ space = __tcp_space_from_win(mptcp_sk(sk)->scaling_ratio, val);
+ if (space <= sk->sk_rcvbuf)
+ return 0;
+
+ /* propagate the rcvbuf changes to all the subflows */
+ WRITE_ONCE(sk->sk_rcvbuf, space);
+ mptcp_for_each_subflow(mptcp_sk(sk), subflow) {
+ struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+ bool slow;
+
+ slow = lock_sock_fast(ssk);
+ WRITE_ONCE(ssk->sk_rcvbuf, space);
+ tcp_sk(ssk)->window_clamp = val;
+ unlock_sock_fast(ssk, slow);
+ }
+ return 0;
+}
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index dbc7a52b322f5..080b16426222d 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1405,10 +1405,18 @@ static void subflow_data_ready(struct sock *sk)
WARN_ON_ONCE(!__mptcp_check_fallback(msk) && !subflow->mp_capable &&
!subflow->mp_join && !(state & TCPF_CLOSE));
- if (mptcp_subflow_data_available(sk))
+ if (mptcp_subflow_data_available(sk)) {
mptcp_data_ready(parent, sk);
- else if (unlikely(sk->sk_err))
+
+ /* subflow-level lowat test are not relevant.
+ * respect the msk-level threshold eventually mandating an immediate ack
+ */
+ if (mptcp_data_avail(msk) < parent->sk_rcvlowat &&
+ (tcp_sk(sk)->rcv_nxt - tcp_sk(sk)->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss)
+ inet_csk(sk)->icsk_ack.pending |= ICSK_ACK_NOW;
+ } else if (unlikely(sk->sk_err)) {
subflow_error_report(sk);
+ }
}
static void subflow_write_space(struct sock *ssk)