[PATCH v6 mptcp-next 01/22] mptcp: add csum_enabled in mptcp_sock

[Paolo Abeni <pabeni@redhat.com>]

From: Geliang Tang <geliangtang@gmail.com>

This patch added a new member named csum_enabled in struct mptcp_sock,
used a dummy mptcp_is_checksum_enabled() helper to initialize it.

Also added a new member named mptcpi_csum_enabled in struct mptcp_info
to expose the csum_enabled flag.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
---
 include/uapi/linux/mptcp.h | 1 +
 net/mptcp/mptcp_diag.c     | 1 +
 net/mptcp/protocol.c       | 1 +
 net/mptcp/protocol.h       | 2 ++
 4 files changed, 5 insertions(+)

diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index 8eb3c0844bff..7b05f7102321 100644
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -105,6 +105,7 @@ struct mptcp_info {
 	__u64	mptcpi_rcv_nxt;
 	__u8	mptcpi_local_addr_used;
 	__u8	mptcpi_local_addr_max;
+	__u8	mptcpi_csum_enabled;
 };
 
 /*
diff --git a/net/mptcp/mptcp_diag.c b/net/mptcp/mptcp_diag.c
index f16d9b5ee978..8f88ddeab6a2 100644
--- a/net/mptcp/mptcp_diag.c
+++ b/net/mptcp/mptcp_diag.c
@@ -144,6 +144,7 @@ static void mptcp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
 	info->mptcpi_write_seq = READ_ONCE(msk->write_seq);
 	info->mptcpi_snd_una = READ_ONCE(msk->snd_una);
 	info->mptcpi_rcv_nxt = READ_ONCE(msk->ack_seq);
+	info->mptcpi_csum_enabled = READ_ONCE(msk->csum_enabled);
 	unlock_sock_fast(sk, slow);
 }
 
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index aec8e77b18e4..4cf8965fae4a 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -2411,6 +2411,7 @@ static int __mptcp_init_sock(struct sock *sk)
 	msk->ack_hint = NULL;
 	msk->first = NULL;
 	inet_csk(sk)->icsk_sync_mss = mptcp_sync_mss;
+	WRITE_ONCE(msk->csum_enabled, mptcp_is_checksum_enabled(sock_net(sk)));
 
 	mptcp_pm_data_init(msk);
 
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index d230a75af631..6cbbe7403402 100644
--- a/net/mptcp/protocol.h
+++ b/net/mptcp/protocol.h
@@ -234,6 +234,7 @@ struct mptcp_sock {
 	bool		snd_data_fin_enable;
 	bool		rcv_fastclose;
 	bool		use_64bit_ack; /* Set when we received a 64-bit DSN */
+	bool		csum_enabled;
 	spinlock_t	join_list_lock;
 	struct sock	*ack_hint;
 	struct work_struct work;
@@ -524,6 +525,7 @@ static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *su
 
 int mptcp_is_enabled(struct net *net);
 unsigned int mptcp_get_add_addr_timeout(struct net *net);
+static inline int mptcp_is_checksum_enabled(struct net *net) { return false; }
 void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow,
 				     struct mptcp_options_received *mp_opt);
 bool mptcp_subflow_data_available(struct sock *sk);
-- 
2.26.2