1 files changed, 23 insertions, 41 deletions

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 2b1982fe1632..7868207c4e9d 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -107,8 +107,8 @@ static void remote_address(const struct sock_common *skc,
 #endif
 }
 
-static bool lookup_subflow_by_saddr(const struct list_head *list,
-				    const struct mptcp_addr_info *saddr)
+bool mptcp_lookup_subflow_by_saddr(const struct list_head *list,
+				   const struct mptcp_addr_info *saddr)
 {
 	struct mptcp_subflow_context *subflow;
 	struct mptcp_addr_info cur;
@@ -977,7 +977,7 @@ static void __mptcp_pm_release_addr_entry(struct mptcp_pm_addr_entry *entry)
 
 static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
 					     struct mptcp_pm_addr_entry *entry,
-					     bool needs_id)
+					     bool needs_id, bool replace)
 {
 	struct mptcp_pm_addr_entry *cur, *del_entry = NULL;
 	unsigned int addr_max;
@@ -1017,6 +1017,17 @@ static int mptcp_pm_nl_append_new_local_addr(struct pm_nl_pernet *pernet,
 			if (entry->addr.id)
 				goto out;
 
+			/* allow callers that only need to look up the local
+			 * addr's id to skip replacement. This allows them to
+			 * avoid calling synchronize_rcu in the packet recv
+			 * path.
+			 */
+			if (!replace) {
+				kfree(entry);
+				ret = cur->addr.id;
+				goto out;
+			}
+
 			pernet->addrs--;
 			entry->addr.id = cur->addr.id;
 			list_del_rcu(&cur->list);
@@ -1165,7 +1176,7 @@ int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc
 	entry->ifindex = 0;
 	entry->flags = MPTCP_PM_ADDR_FLAG_IMPLICIT;
 	entry->lsk = NULL;
-	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true);
+	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry, true, false);
 	if (ret < 0)
 		kfree(entry);
 
@@ -1433,7 +1444,8 @@ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
 		}
 	}
 	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry,
-						!mptcp_pm_has_addr_attr_id(attr, info));
+						!mptcp_pm_has_addr_attr_id(attr, info),
+						true);
 	if (ret < 0) {
 		GENL_SET_ERR_MSG_FMT(info, "too many addresses or duplicate one: %d", ret);
 		goto out_free;
@@ -1447,8 +1459,8 @@ out_free:
 	return ret;
 }
 
-static bool remove_anno_list_by_saddr(struct mptcp_sock *msk,
-				      const struct mptcp_addr_info *addr)
+bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
+				     const struct mptcp_addr_info *addr)
 {
 	struct mptcp_pm_add_entry *entry;
 
@@ -1476,7 +1488,7 @@ static bool mptcp_pm_remove_anno_addr(struct mptcp_sock *msk,
 
 	list.ids[list.nr++] = mptcp_endp_get_local_id(msk, addr);
 
-	ret = remove_anno_list_by_saddr(msk, addr);
+	ret = mptcp_remove_anno_list_by_saddr(msk, addr);
 	if (ret || force) {
 		spin_lock_bh(&msk->pm.lock);
 		if (ret) {
@@ -1515,7 +1527,7 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 			goto next;
 
 		lock_sock(sk);
-		remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr);
+		remove_subflow = mptcp_lookup_subflow_by_saddr(&msk->conn_list, addr);
 		mptcp_pm_remove_anno_addr(msk, addr, remove_subflow &&
 					  !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT));
 
@@ -1628,36 +1640,6 @@ int mptcp_pm_nl_del_addr_doit(struct sk_buff *skb, struct genl_info *info)
 	return ret;
 }
 
-/* Called from the userspace PM only */
-void mptcp_pm_remove_addrs(struct mptcp_sock *msk, struct list_head *rm_list)
-{
-	struct mptcp_rm_list alist = { .nr = 0 };
-	struct mptcp_pm_addr_entry *entry;
-	int anno_nr = 0;
-
-	list_for_each_entry(entry, rm_list, list) {
-		if (alist.nr >= MPTCP_RM_IDS_MAX)
-			break;
-
-		/* only delete if either announced or matching a subflow */
-		if (remove_anno_list_by_saddr(msk, &entry->addr))
-			anno_nr++;
-		else if (!lookup_subflow_by_saddr(&msk->conn_list,
-						  &entry->addr))
-			continue;
-
-		alist.ids[alist.nr++] = entry->addr.id;
-	}
-
-	if (alist.nr) {
-		spin_lock_bh(&msk->pm.lock);
-		msk->pm.add_addr_signaled -= anno_nr;
-		mptcp_pm_remove_addr(msk, &alist);
-		spin_unlock_bh(&msk->pm.lock);
-	}
-}
-
-/* Called from the in-kernel PM only */
 static void mptcp_pm_flush_addrs_and_subflows(struct mptcp_sock *msk,
 					      struct list_head *rm_list)
 {
@@ -1666,11 +1648,11 @@ static void mptcp_pm_flush_addrs_and_subflows(struct mptcp_sock *msk,
 
 	list_for_each_entry(entry, rm_list, list) {
 		if (slist.nr < MPTCP_RM_IDS_MAX &&
-		    lookup_subflow_by_saddr(&msk->conn_list, &entry->addr))
+		    mptcp_lookup_subflow_by_saddr(&msk->conn_list, &entry->addr))
 			slist.ids[slist.nr++] = mptcp_endp_get_local_id(msk, &entry->addr);
 
 		if (alist.nr < MPTCP_RM_IDS_MAX &&
-		    remove_anno_list_by_saddr(msk, &entry->addr))
+		    mptcp_remove_anno_list_by_saddr(msk, &entry->addr))
 			alist.ids[alist.nr++] = mptcp_endp_get_local_id(msk, &entry->addr);
 	}