mptcp: change add_addr_signal type

This patch changed the 'add_addr_signal' type from bool to char, so that
we could encode the addr type there.
Suggested-by: NPaolo Abeni <pabeni@redhat.com>
Acked-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Signed-off-by: NMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

net/mptcp/pm.c

@@ -16,11 +16,15 @@ int mptcp_pm_announce_addr(struct mptcp_sock *msk,
 			   const struct mptcp_addr_info *addr,
 			   bool echo)
 {
+	u8 add_addr = READ_ONCE(msk->pm.add_addr_signal);
+
 	pr_debug("msk=%p, local_id=%d", msk, addr->id);
 
 	msk->pm.local = *addr;
-	WRITE_ONCE(msk->pm.add_addr_echo, echo);
-	WRITE_ONCE(msk->pm.add_addr_signal, true);
+	add_addr |= BIT(MPTCP_ADD_ADDR_SIGNAL);
+	if (echo)
+		add_addr |= BIT(MPTCP_ADD_ADDR_ECHO);
+	WRITE_ONCE(msk->pm.add_addr_signal, add_addr);
 	return 0;
 }
 
@@ -182,13 +186,13 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 	if (!mptcp_pm_should_add_signal(msk))
 		goto out_unlock;
 
-	*echo = READ_ONCE(msk->pm.add_addr_echo);
+	*echo = mptcp_pm_should_add_signal_echo(msk);
 
 	if (remaining < mptcp_add_addr_len(msk->pm.local.family, *echo))
 		goto out_unlock;
 
 	*saddr = msk->pm.local;
-	WRITE_ONCE(msk->pm.add_addr_signal, false);
+	WRITE_ONCE(msk->pm.add_addr_signal, 0);
 	ret = true;
 
 out_unlock:
@@ -232,11 +236,10 @@ void mptcp_pm_data_init(struct mptcp_sock *msk)
 	msk->pm.subflows = 0;
 	msk->pm.rm_id = 0;
 	WRITE_ONCE(msk->pm.work_pending, false);
-	WRITE_ONCE(msk->pm.add_addr_signal, false);
+	WRITE_ONCE(msk->pm.add_addr_signal, 0);
 	WRITE_ONCE(msk->pm.rm_addr_signal, false);
 	WRITE_ONCE(msk->pm.accept_addr, false);
 	WRITE_ONCE(msk->pm.accept_subflow, false);
-	WRITE_ONCE(msk->pm.add_addr_echo, false);
 	msk->pm.status = 0;
 
 	spin_lock_init(&msk->pm.lock);

net/mptcp/protocol.h

@@ -165,6 +165,11 @@ enum mptcp_pm_status {
 	MPTCP_PM_SUBFLOW_ESTABLISHED,
 };
 
+enum mptcp_add_addr_status {
+	MPTCP_ADD_ADDR_SIGNAL,
+	MPTCP_ADD_ADDR_ECHO,
+};
+
 struct mptcp_pm_data {
 	struct mptcp_addr_info local;
 	struct mptcp_addr_info remote;
@@ -172,13 +177,12 @@ struct mptcp_pm_data {
 
 	spinlock_t	lock;		/*protects the whole PM data */
 
-	bool		add_addr_signal;
+	u8		add_addr_signal;
 	bool		rm_addr_signal;
 	bool		server_side;
 	bool		work_pending;
 	bool		accept_addr;
 	bool		accept_subflow;
-	bool		add_addr_echo;
 	u8		add_addr_signaled;
 	u8		add_addr_accepted;
 	u8		local_addr_used;
@@ -516,7 +520,12 @@ int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 local_id);
 
 static inline bool mptcp_pm_should_add_signal(struct mptcp_sock *msk)
 {
-	return READ_ONCE(msk->pm.add_addr_signal);
+	return READ_ONCE(msk->pm.add_addr_signal) & BIT(MPTCP_ADD_ADDR_SIGNAL);
+}
+
+static inline bool mptcp_pm_should_add_signal_echo(struct mptcp_sock *msk)
+{
+	return READ_ONCE(msk->pm.add_addr_signal) & BIT(MPTCP_ADD_ADDR_ECHO);
 }
 
 static inline bool mptcp_pm_should_rm_signal(struct mptcp_sock *msk)