Merge branch 'mptcp-pm-userspace-misc-cleanups'

Matthieu Baerts says:

====================
mptcp: pm: userspace: misc cleanups

These cleanups lead the way to the unification of the path-manager
interfaces, and allow future extensions. The following patches are not
linked to each others, but are all related to the userspace
path-manager.

- Patch 1: add a new helper to reduce duplicated code.

- Patch 2: add a macro to iterate over the address list, clearer.

- Patch 3: reduce duplicated code to get the corresponding MPTCP socket.

- Patch 4: move userspace PM specific code out of the in-kernel one.

- Patch 5: pass an entry instead of a list with always one entry.

- Patch 6: uniform struct type used for the local addresses.

- Patch 7: simplify error handling.
====================

Link: https://patch.msgid.link/20241213-net-next-mptcp-pm-misc-cleanup-v1-0-ddb6d00109a8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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;
@@ -1447,8 +1447,8 @@ int mptcp_pm_nl_add_addr_doit(struct sk_buff *skb, struct genl_info *info)
 	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 +1476,7 @@ 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) {
@@ -1520,7 +1520,7 @@ static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 		}
 
 		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));
 
@@ -1633,36 +1633,6 @@ 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)
 {
@@ -1671,11 +1641,11 @@ 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);
 	}