2 files changed, 32 insertions, 18 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index f21610c5da1a..3e14d38e5d42 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -376,17 +376,12 @@ struct tcf_net {
 static unsigned int tcf_net_id;
 
 static int tcf_block_insert(struct tcf_block *block, struct net *net,
-			    u32 block_index, struct netlink_ext_ack *extack)
+			    struct netlink_ext_ack *extack)
 {
 	struct tcf_net *tn = net_generic(net, tcf_net_id);
-	int err;
 
-	err = idr_alloc_u32(&tn->idr, block, &block_index, block_index,
-			    GFP_KERNEL);
-	if (err)
-		return err;
-	block->index = block_index;
-	return 0;
+	return idr_alloc_u32(&tn->idr, block, &block->index, block->index,
+			     GFP_KERNEL);
 }
 
 static void tcf_block_remove(struct tcf_block *block, struct net *net)
@@ -397,6 +392,7 @@ static void tcf_block_remove(struct tcf_block *block, struct net *net)
 }
 
 static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
+					  u32 block_index,
 					  struct netlink_ext_ack *extack)
 {
 	struct tcf_block *block;
@@ -419,10 +415,13 @@ static struct tcf_block *tcf_block_create(struct net *net, struct Qdisc *q,
 		err = -ENOMEM;
 		goto err_chain_create;
 	}
-	block->net = qdisc_net(q);
 	block->refcnt = 1;
 	block->net = net;
-	block->q = q;
+	block->index = block_index;
+
+	/* Don't store q pointer for blocks which are shared */
+	if (!tcf_block_shared(block))
+		block->q = q;
 	return block;
 
 err_chain_create:
@@ -518,13 +517,12 @@ int tcf_block_get_ext(struct tcf_block **p_block, struct Qdisc *q,
 	}
 
 	if (!block) {
-		block = tcf_block_create(net, q, extack);
+		block = tcf_block_create(net, q, ei->block_index, extack);
 		if (IS_ERR(block))
 			return PTR_ERR(block);
 		created = true;
-		if (ei->block_index) {
-			err = tcf_block_insert(block, net,
-					       ei->block_index, extack);
+		if (tcf_block_shared(block)) {
+			err = tcf_block_insert(block, net, extack);
 			if (err)
 				goto err_block_insert;
 		}
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 6c7601a530e3..ed8b6a24b9e9 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -96,7 +96,7 @@ struct tc_u_hnode {
 
 struct tc_u_common {
 	struct tc_u_hnode __rcu	*hlist;
-	struct tcf_block	*block;
+	void			*ptr;
 	int			refcnt;
 	struct idr		handle_idr;
 	struct hlist_node	hnode;
@@ -330,9 +330,25 @@ static struct hlist_head *tc_u_common_hash;
 #define U32_HASH_SHIFT 10
 #define U32_HASH_SIZE (1 << U32_HASH_SHIFT)
 
+static void *tc_u_common_ptr(const struct tcf_proto *tp)
+{
+	struct tcf_block *block = tp->chain->block;
+
+	/* The block sharing is currently supported only
+	 * for classless qdiscs. In that case we use block
+	 * for tc_u_common identification. In case the
+	 * block is not shared, block->q is a valid pointer
+	 * and we can use that. That works for classful qdiscs.
+	 */
+	if (tcf_block_shared(block))
+		return block;
+	else
+		return block->q;
+}
+
 static unsigned int tc_u_hash(const struct tcf_proto *tp)
 {
-	return hash_ptr(tp->chain->block, U32_HASH_SHIFT);
+	return hash_ptr(tc_u_common_ptr(tp), U32_HASH_SHIFT);
 }
 
 static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
@@ -342,7 +358,7 @@ static struct tc_u_common *tc_u_common_find(const struct tcf_proto *tp)
 
 	h = tc_u_hash(tp);
 	hlist_for_each_entry(tc, &tc_u_common_hash[h], hnode) {
-		if (tc->block == tp->chain->block)
+		if (tc->ptr == tc_u_common_ptr(tp))
 			return tc;
 	}
 	return NULL;
@@ -371,7 +387,7 @@ static int u32_init(struct tcf_proto *tp)
 			kfree(root_ht);
 			return -ENOBUFS;
 		}
-		tp_c->block = tp->chain->block;
+		tp_c->ptr = tc_u_common_ptr(tp);
 		INIT_HLIST_NODE(&tp_c->hnode);
 		idr_init(&tp_c->handle_idr);