mptcp: remove multi addresses and subflows in PM

This patch implemented the function to remove a list of addresses and
subflows, named mptcp_nl_remove_addrs_list, which had a input parameter
rm_list as the removing addresses list.

In mptcp_nl_remove_addrs_list, traverse all the existing msk sockets to
invoke mptcp_pm_remove_addrs_and_subflows to remove a list of addresses
for each msk socket.

In mptcp_pm_remove_addrs_and_subflows, traverse all the addresses in the
removing addresses list, to find whether this address is in the conn_list
or anno_list. If it is, put the address ID into the removing address list
or the removing subflow list, and pass the two lists to
mptcp_pm_remove_addr and 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_netlink.c

@@ -1200,6 +1200,54 @@ static int mptcp_nl_cmd_del_addr(struct sk_buff *skb, struct genl_info *info)
 	return ret;
 }
 
+static void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
+					       struct list_head *rm_list)
+{
+	struct mptcp_rm_list alist = { .nr = 0 }, slist = { .nr = 0 };
+	struct mptcp_pm_addr_entry *entry;
+
+	list_for_each_entry(entry, rm_list, list) {
+		if (lookup_subflow_by_saddr(&msk->conn_list, &entry->addr) &&
+		    alist.nr < MPTCP_RM_IDS_MAX &&
+		    slist.nr < MPTCP_RM_IDS_MAX) {
+			alist.ids[alist.nr++] = entry->addr.id;
+			slist.ids[slist.nr++] = entry->addr.id;
+		} else if (remove_anno_list_by_saddr(msk, &entry->addr) &&
+			 alist.nr < MPTCP_RM_IDS_MAX) {
+			alist.ids[alist.nr++] = entry->addr.id;
+		}
+	}
+
+	if (alist.nr) {
+		spin_lock_bh(&msk->pm.lock);
+		mptcp_pm_remove_addr(msk, &alist);
+		spin_unlock_bh(&msk->pm.lock);
+	}
+	if (slist.nr)
+		mptcp_pm_remove_subflow(msk, &slist);
+}
+
+static void mptcp_nl_remove_addrs_list(struct net *net,
+				       struct list_head *rm_list)
+{
+	long s_slot = 0, s_num = 0;
+	struct mptcp_sock *msk;
+
+	if (list_empty(rm_list))
+		return;
+
+	while ((msk = mptcp_token_iter_next(net, &s_slot, &s_num)) != NULL) {
+		struct sock *sk = (struct sock *)msk;
+
+		lock_sock(sk);
+		mptcp_pm_remove_addrs_and_subflows(msk, rm_list);
+		release_sock(sk);
+
+		sock_put(sk);
+		cond_resched();
+	}
+}
+
 static void __flush_addrs(struct net *net, struct list_head *list)
 {
 	while (!list_empty(list)) {