--- zzzz-none-000/linux-5.4.213/net/ipv4/ipmr.c	2022-09-15 10:04:56.000000000 +0000
+++ alder-5690pro-762/linux-5.4.213/net/ipv4/ipmr.c	2024-08-14 09:02:13.000000000 +0000
@@ -84,6 +84,9 @@
 /* Special spinlock for queue of unresolved entries */
 static DEFINE_SPINLOCK(mfc_unres_lock);
 
+/* spinlock for offload */
+static DEFINE_SPINLOCK(lock);
+
 /* We return to original Alan's scheme. Hash table of resolved
  * entries is changed only in process context and protected
  * with weak lock mrt_lock. Queue of unresolved entries is protected
@@ -107,6 +110,9 @@
 static void igmpmsg_netlink_event(struct mr_table *mrt, struct sk_buff *pkt);
 static void mroute_clean_tables(struct mr_table *mrt, int flags);
 static void ipmr_expire_process(struct timer_list *t);
+static struct mfc_cache *ipmr_cache_find(struct mr_table *mrt, __be32 origin,
+					 __be32 mcastgrp);
+static ipmr_mfc_event_offload_callback_t __rcu ipmr_mfc_event_offload_callback;
 
 #ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
 #define ipmr_for_each_table(mrt, net) \
@@ -173,6 +179,7 @@
 	case FR_ACT_UNREACHABLE:
 		return -ENETUNREACH;
 	case FR_ACT_PROHIBIT:
+	case FR_ACT_POLICY_FAILED:
 		return -EACCES;
 	case FR_ACT_BLACKHOLE:
 	default:
@@ -219,6 +226,78 @@
 	return 0;
 }
 
+/* ipmr_sync_entry_update()
+ * Call the registered offload callback to report an update to a multicast
+ * route entry. The callback receives the list of destination interfaces and
+ * the interface count
+ */
+static void ipmr_sync_entry_update(struct mr_table *mrt,
+				   struct mfc_cache *cache)
+{
+	int vifi, dest_if_count = 0;
+	u32 dest_dev[MAXVIFS];
+	__be32  origin;
+	__be32  group;
+	ipmr_mfc_event_offload_callback_t offload_update_cb_f;
+
+	memset(dest_dev, 0, sizeof(dest_dev));
+
+	origin = cache->mfc_origin;
+	group = cache->mfc_mcastgrp;
+
+	read_lock(&mrt_lock);
+	for (vifi = 0; vifi < cache->_c.mfc_un.res.maxvif; vifi++) {
+		if (!((cache->_c.mfc_un.res.ttls[vifi] > 0) &&
+		      (cache->_c.mfc_un.res.ttls[vifi] < 255))) {
+			continue;
+		}
+		if (dest_if_count == MAXVIFS) {
+			read_unlock(&mrt_lock);
+			return;
+		}
+
+		if (!VIF_EXISTS(mrt, vifi)) {
+			read_unlock(&mrt_lock);
+			return;
+		}
+		dest_dev[dest_if_count] = mrt->vif_table[vifi].dev->ifindex;
+		dest_if_count++;
+	}
+	read_unlock(&mrt_lock);
+
+	rcu_read_lock();
+	offload_update_cb_f = rcu_dereference(ipmr_mfc_event_offload_callback);
+
+	if (!offload_update_cb_f) {
+		rcu_read_unlock();
+		return;
+	}
+
+	offload_update_cb_f(group, origin, dest_if_count, dest_dev,
+			    IPMR_MFC_EVENT_UPDATE);
+	rcu_read_unlock();
+}
+
+/* ipmr_sync_entry_delete()
+ * Call the registered offload callback to inform of a multicast route entry
+ * delete event
+ */
+static void ipmr_sync_entry_delete(u32 origin, u32 group)
+{
+	ipmr_mfc_event_offload_callback_t offload_update_cb_f;
+
+	rcu_read_lock();
+	offload_update_cb_f = rcu_dereference(ipmr_mfc_event_offload_callback);
+
+	if (!offload_update_cb_f) {
+		rcu_read_unlock();
+		return;
+	}
+
+	offload_update_cb_f(group, origin, 0, NULL, IPMR_MFC_EVENT_DELETE);
+	rcu_read_unlock();
+}
+
 static const struct fib_rules_ops __net_initconst ipmr_rules_ops_template = {
 	.family		= RTNL_FAMILY_IPMR,
 	.rule_size	= sizeof(struct ipmr_rule),
@@ -233,6 +312,154 @@
 	.owner		= THIS_MODULE,
 };
 
+/* ipmr_register_mfc_event_offload_callback()
+ * Register the IPv4 Multicast update offload callback with IPMR
+ */
+bool ipmr_register_mfc_event_offload_callback(
+		ipmr_mfc_event_offload_callback_t mfc_offload_cb)
+{
+	ipmr_mfc_event_offload_callback_t offload_update_cb_f;
+
+	rcu_read_lock();
+	offload_update_cb_f = rcu_dereference(ipmr_mfc_event_offload_callback);
+
+	if (offload_update_cb_f) {
+		rcu_read_unlock();
+		return false;
+	}
+	rcu_read_unlock();
+
+	spin_lock(&lock);
+	rcu_assign_pointer(ipmr_mfc_event_offload_callback, mfc_offload_cb);
+	spin_unlock(&lock);
+	synchronize_rcu();
+	return true;
+}
+EXPORT_SYMBOL(ipmr_register_mfc_event_offload_callback);
+
+/* ipmr_unregister_mfc_event_offload_callback()
+ * De-register the IPv4 Multicast update offload callback with IPMR
+ */
+void ipmr_unregister_mfc_event_offload_callback(void)
+{
+	spin_lock(&lock);
+	rcu_assign_pointer(ipmr_mfc_event_offload_callback, NULL);
+	spin_unlock(&lock);
+	synchronize_rcu();
+}
+EXPORT_SYMBOL(ipmr_unregister_mfc_event_offload_callback);
+
+/* ipmr_find_mfc_entry()
+ * Returns destination interface list for a particular multicast flow, and
+ * the number of interfaces in the list
+ */
+int ipmr_find_mfc_entry(struct net *net, __be32 origin, __be32 group,
+			u32 max_dest_cnt, u32 dest_dev[])
+{
+	int vifi, dest_if_count = 0;
+	struct mr_table *mrt;
+	struct mfc_cache *cache;
+
+	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
+	if (!mrt)
+		return -ENOENT;
+
+	rcu_read_lock();
+	cache = ipmr_cache_find(mrt, origin, group);
+	if (!cache) {
+		rcu_read_unlock();
+		return -ENOENT;
+	}
+
+	read_lock(&mrt_lock);
+	for (vifi = 0; vifi < cache->_c.mfc_un.res.maxvif; vifi++) {
+		if (!((cache->_c.mfc_un.res.ttls[vifi] > 0) &&
+		      (cache->_c.mfc_un.res.ttls[vifi] < 255))) {
+			continue;
+		}
+
+		/* We have another valid destination interface entry. Check if
+		 * the number of the destination interfaces for the route is
+		 * exceeding the size of the array given to us
+		 */
+		if (dest_if_count == max_dest_cnt) {
+			read_unlock(&mrt_lock);
+			rcu_read_unlock();
+			return -EINVAL;
+		}
+
+		if (!VIF_EXISTS(mrt, vifi)) {
+			read_unlock(&mrt_lock);
+			rcu_read_unlock();
+			return -EINVAL;
+		}
+
+		dest_dev[dest_if_count] = mrt->vif_table[vifi].dev->ifindex;
+		dest_if_count++;
+	}
+	read_unlock(&mrt_lock);
+	rcu_read_unlock();
+
+	return dest_if_count;
+}
+EXPORT_SYMBOL(ipmr_find_mfc_entry);
+
+/* ipmr_mfc_stats_update()
+ * Update the MFC/VIF statistics for offloaded flows
+ */
+int ipmr_mfc_stats_update(struct net *net, __be32 origin, __be32 group,
+			  u64 pkts_in, u64 bytes_in,
+			  u64 pkts_out, u64 bytes_out)
+{
+	int vif, vifi;
+	struct mr_table *mrt;
+	struct mfc_cache *cache;
+
+	mrt = ipmr_get_table(net, RT_TABLE_DEFAULT);
+	if (!mrt)
+		return -ENOENT;
+
+	rcu_read_lock();
+	cache = ipmr_cache_find(mrt, origin, group);
+	if (!cache) {
+		rcu_read_unlock();
+		return -ENOENT;
+	}
+
+	vif = cache->_c.mfc_parent;
+
+	read_lock(&mrt_lock);
+	if (!VIF_EXISTS(mrt, vif)) {
+		read_unlock(&mrt_lock);
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+
+	mrt->vif_table[vif].pkt_in += pkts_in;
+	mrt->vif_table[vif].bytes_in += bytes_in;
+	cache->_c.mfc_un.res.pkt  += pkts_out;
+	cache->_c.mfc_un.res.bytes += bytes_out;
+
+	for (vifi = cache->_c.mfc_un.res.minvif;
+			vifi < cache->_c.mfc_un.res.maxvif; vifi++) {
+		if ((cache->_c.mfc_un.res.ttls[vifi] > 0) &&
+		    (cache->_c.mfc_un.res.ttls[vifi] < 255)) {
+			if (!VIF_EXISTS(mrt, vifi)) {
+				read_unlock(&mrt_lock);
+				rcu_read_unlock();
+				return -EINVAL;
+			}
+			mrt->vif_table[vifi].pkt_out += pkts_out;
+			mrt->vif_table[vifi].bytes_out += bytes_out;
+		}
+	}
+	read_unlock(&mrt_lock);
+	rcu_read_unlock();
+
+	return 0;
+}
+EXPORT_SYMBOL(ipmr_mfc_stats_update);
+
 static int __net_init ipmr_rules_init(struct net *net)
 {
 	struct fib_rules_ops *ops;
@@ -1208,6 +1435,8 @@
 	call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, c, mrt->id);
 	mroute_netlink_event(mrt, c, RTM_DELROUTE);
 	mr_cache_put(&c->_c);
+	/* Inform offload modules of the delete event */
+	ipmr_sync_entry_delete(c->mfc_origin, c->mfc_mcastgrp);
 
 	return 0;
 }
@@ -1238,6 +1467,8 @@
 		call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_REPLACE, c,
 					      mrt->id);
 		mroute_netlink_event(mrt, c, RTM_NEWROUTE);
+		/* Inform offload modules of the update event */
+		ipmr_sync_entry_update(mrt, c);
 		return 0;
 	}
 
@@ -1298,6 +1529,7 @@
 	struct net *net = read_pnet(&mrt->net);
 	struct mr_mfc *c, *tmp;
 	struct mfc_cache *cache;
+	u32 origin, group;
 	LIST_HEAD(list);
 	int i;
 
@@ -1322,10 +1554,14 @@
 			rhltable_remove(&mrt->mfc_hash, &c->mnode, ipmr_rht_params);
 			list_del_rcu(&c->list);
 			cache = (struct mfc_cache *)c;
+			origin = cache->mfc_origin;
+			group = cache->mfc_mcastgrp;
 			call_ipmr_mfc_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, cache,
 						      mrt->id);
 			mroute_netlink_event(mrt, cache, RTM_DELROUTE);
 			mr_cache_put(c);
+			/* Inform offload modules of the delete event */
+			ipmr_sync_entry_delete(origin, group);
 		}
 	}
 
@@ -2952,7 +3188,7 @@
 				    vif->dev->name : "none";
 
 		seq_printf(seq,
-			   "%2td %-10s %8ld %7ld  %8ld %7ld %05X %08X %08X\n",
+			   "%2td %-10s %8llu %7llu  %8llu %7llu %05X %08X %08X\n",
 			   vif - mrt->vif_table,
 			   name, vif->bytes_in, vif->pkt_in,
 			   vif->bytes_out, vif->pkt_out,