mptcp: remove multi subflows in PM

This patch dealt with removing multi subflows in PM:

In mptcp_pm_remove_subflow, changed the input parameter local_id as an
list of removing address ids, and passed the list to
mptcp_pm_nl_rm_subflow_received.

In mptcp_pm_nl_rm_subflow_received, iterated each address id from the
received ids list. Then shut down and closed each address id's subsocket.

In mptcp_nl_remove_subflow_and_signal_addr, put the single address id into
an ids list, and passed it to mptcp_pm_remove_subflow.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/mptcp/pm.c

@@ -56,12 +56,12 @@ int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_
 	return 0;
 }
 
-int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 local_id)
+int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list)
 {
-	pr_debug("msk=%p, local_id=%d", msk, local_id);
+	pr_debug("msk=%p, rm_list_nr=%d", msk, rm_list->nr);
 
 	spin_lock_bh(&msk->pm.lock);
-	mptcp_pm_nl_rm_subflow_received(msk, local_id);
+	mptcp_pm_nl_rm_subflow_received(msk, rm_list);
 	spin_unlock_bh(&msk->pm.lock);
 	return 0;
 }

net/mptcp/pm_netlink.c

@@ -645,39 +645,44 @@ void mptcp_pm_nl_work(struct mptcp_sock *msk)
 	spin_unlock_bh(&msk->pm.lock);
 }
 
-void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, u8 rm_id)
+void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
+				     const struct mptcp_rm_list *rm_list)
 {
 	struct mptcp_subflow_context *subflow, *tmp;
 	struct sock *sk = (struct sock *)msk;
+	u8 i;
 
-	pr_debug("subflow rm_id %d", rm_id);
+	pr_debug("subflow rm_list_nr %d", rm_list->nr);
 
 	msk_owned_by_me(msk);
 
-	if (!rm_id)
+	if (!rm_list->nr)
 		return;
 
 	if (list_empty(&msk->conn_list))
 		return;
 
-	list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) {
-		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
-		int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
+	for (i = 0; i < rm_list->nr; i++) {
+		list_for_each_entry_safe(subflow, tmp, &msk->conn_list, node) {
+			struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
+			int how = RCV_SHUTDOWN | SEND_SHUTDOWN;
 
-		if (rm_id != subflow->local_id)
-			continue;
+			if (rm_list->ids[i] != subflow->local_id)
+				continue;
 
-		spin_unlock_bh(&msk->pm.lock);
-		mptcp_subflow_shutdown(sk, ssk, how);
-		mptcp_close_ssk(sk, ssk, subflow);
-		spin_lock_bh(&msk->pm.lock);
+			pr_debug(" -> subflow rm_list_ids[%d]=%u", i, rm_list->ids[i]);
+			spin_unlock_bh(&msk->pm.lock);
+			mptcp_subflow_shutdown(sk, ssk, how);
+			mptcp_close_ssk(sk, ssk, subflow);
+			spin_lock_bh(&msk->pm.lock);
 
-		msk->pm.local_addr_used--;
-		msk->pm.subflows--;
+			msk->pm.local_addr_used--;
+			msk->pm.subflows--;
 
-		__MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
+			__MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_RMSUBFLOW);
 
-		break;
+			break;
+		}
 	}
 }
 
@@ -1094,9 +1099,12 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 {
 	struct mptcp_sock *msk;
 	long s_slot = 0, s_num = 0;
+	struct mptcp_rm_list list = { .nr = 0 };
 
 	pr_debug("remove_id=%d", addr->id);
 
+	list.ids[list.nr++] = addr->id;
+
 	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
 		struct sock *sk = (struct sock *)msk;
 		bool remove_subflow;
@@ -1110,7 +1118,7 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 		remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr);
 		mptcp_pm_remove_anno_addr(msk, addr, remove_subflow);
 		if (remove_subflow)
-			mptcp_pm_remove_subflow(msk, addr->id);
+			mptcp_pm_remove_subflow(msk, &list);
 		release_sock(sk);
 
 next:

net/mptcp/protocol.h

@@ -664,7 +664,7 @@ int mptcp_pm_announce_addr(struct mptcp_sock *msk,
 			   const struct mptcp_addr_info *addr,
 			   bool echo, bool port);
 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
-int mptcp_pm_remove_subflow(struct mptcp_sock *msk, u8 local_id);
+int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
 
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		 const struct sock *ssk, gfp_t gfp);
@@ -728,7 +728,8 @@ int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
 void __init mptcp_pm_nl_init(void);
 void mptcp_pm_nl_data_init(struct mptcp_sock *msk);
 void mptcp_pm_nl_work(struct mptcp_sock *msk);
-void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk, u8 rm_id);
+void mptcp_pm_nl_rm_subflow_received(struct mptcp_sock *msk,
+				     const struct mptcp_rm_list *rm_list);
 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
 unsigned int mptcp_pm_get_add_addr_signal_max(struct mptcp_sock *msk);
 unsigned int mptcp_pm_get_add_addr_accept_max(struct mptcp_sock *msk);