net: sched: add block bind/unbind notif. and extended block_get/put

Introduce new type of ndo_setup_tc message to propage binding/unbinding
of a block to driver. Call this ndo whenever qdisc gets/puts a block.
Alongside with this, there's need to propagate binder type from qdisc
code down to the notifier. So introduce extended variants of
block_get/put in order to pass this info.

Signed-off-by: Jiri Pirko <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: jpirko

include/linux/netdevice.h

@@ -775,6 +775,7 @@ enum tc_setup_type {
 	TC_SETUP_CLSFLOWER,
 	TC_SETUP_CLSMATCHALL,
 	TC_SETUP_CLSBPF,
+	TC_SETUP_BLOCK,
 };
 
 /* These structures hold the attributes of xdp state that are being passed

include/net/pkt_cls.h

@@ -17,13 +17,27 @@ struct tcf_walker {
 int register_tcf_proto_ops(struct tcf_proto_ops *ops);
 int unregister_tcf_proto_ops(struct tcf_proto_ops *ops);
 
+enum tcf_block_binder_type {
+	TCF_BLOCK_BINDER_TYPE_UNSPEC,
+};
+
+struct tcf_block_ext_info {
+	enum tcf_block_binder_type binder_type;
+};
+
 #ifdef CONFIG_NET_CLS
 struct tcf_chain *tcf_chain_get(struct tcf_block *block, u32 chain_index,
 				bool create);
 void tcf_chain_put(struct tcf_chain *chain);
 int tcf_block_get(struct tcf_block **p_block,
 		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q);
+int tcf_block_get_ext(struct tcf_block **p_block,
+		      struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		      struct tcf_block_ext_info *ei);
 void tcf_block_put(struct tcf_block *block);
+void tcf_block_put_ext(struct tcf_block *block,
+		       struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		       struct tcf_block_ext_info *ei);
 
 static inline struct Qdisc *tcf_block_q(struct tcf_block *block)
 {
@@ -46,10 +60,25 @@ int tcf_block_get(struct tcf_block **p_block,
 	return 0;
 }
 
+static inline
+int tcf_block_get_ext(struct tcf_block **p_block,
+		      struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		      struct tcf_block_ext_info *ei)
+{
+	return 0;
+}
+
 static inline void tcf_block_put(struct tcf_block *block)
 {
 }
 
+static inline
+void tcf_block_put_ext(struct tcf_block *block,
+		       struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		       struct tcf_block_ext_info *ei)
+{
+}
+
 static inline struct Qdisc *tcf_block_q(struct tcf_block *block)
 {
 	return NULL;
@@ -434,6 +463,17 @@ tcf_match_indev(struct sk_buff *skb, int ifindex)
 int tc_setup_cb_call(struct tcf_exts *exts, enum tc_setup_type type,
 		     void *type_data, bool err_stop);
 
+enum tc_block_command {
+	TC_BLOCK_BIND,
+	TC_BLOCK_UNBIND,
+};
+
+struct tc_block_offload {
+	enum tc_block_command command;
+	enum tcf_block_binder_type binder_type;
+	struct tcf_block *block;
+};
+
 struct tc_cls_common_offload {
 	u32 chain_index;
 	__be16 protocol;

net/sched/cls_api.c

@@ -240,8 +240,36 @@ tcf_chain_filter_chain_ptr_set(struct tcf_chain *chain,
 	chain->p_filter_chain = p_filter_chain;
 }
 
-int tcf_block_get(struct tcf_block **p_block,
-		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q)
+static void tcf_block_offload_cmd(struct tcf_block *block, struct Qdisc *q,
+				  struct tcf_block_ext_info *ei,
+				  enum tc_block_command command)
+{
+	struct net_device *dev = q->dev_queue->dev;
+	struct tc_block_offload bo = {};
+
+	if (!tc_can_offload(dev))
+		return;
+	bo.command = command;
+	bo.binder_type = ei->binder_type;
+	bo.block = block;
+	dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_BLOCK, &bo);
+}
+
+static void tcf_block_offload_bind(struct tcf_block *block, struct Qdisc *q,
+				   struct tcf_block_ext_info *ei)
+{
+	tcf_block_offload_cmd(block, q, ei, TC_BLOCK_BIND);
+}
+
+static void tcf_block_offload_unbind(struct tcf_block *block, struct Qdisc *q,
+				     struct tcf_block_ext_info *ei)
+{
+	tcf_block_offload_cmd(block, q, ei, TC_BLOCK_UNBIND);
+}
+
+int tcf_block_get_ext(struct tcf_block **p_block,
+		      struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		      struct tcf_block_ext_info *ei)
 {
 	struct tcf_block *block = kzalloc(sizeof(*block), GFP_KERNEL);
 	struct tcf_chain *chain;
@@ -259,22 +287,36 @@ int tcf_block_get(struct tcf_block **p_block,
 	tcf_chain_filter_chain_ptr_set(chain, p_filter_chain);
 	block->net = qdisc_net(q);
 	block->q = q;
+	tcf_block_offload_bind(block, q, ei);
 	*p_block = block;
 	return 0;
 
 err_chain_create:
 	kfree(block);
 	return err;
 }
+EXPORT_SYMBOL(tcf_block_get_ext);
+
+int tcf_block_get(struct tcf_block **p_block,
+		  struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q)
+{
+	struct tcf_block_ext_info ei = {0, };
+
+	return tcf_block_get_ext(p_block, p_filter_chain, q, &ei);
+}
 EXPORT_SYMBOL(tcf_block_get);
 
-void tcf_block_put(struct tcf_block *block)
+void tcf_block_put_ext(struct tcf_block *block,
+		       struct tcf_proto __rcu **p_filter_chain, struct Qdisc *q,
+		       struct tcf_block_ext_info *ei)
 {
 	struct tcf_chain *chain, *tmp;
 
 	if (!block)
 		return;
 
+	tcf_block_offload_unbind(block, q, ei);
+
 	/* XXX: Standalone actions are not allowed to jump to any chain, and
 	 * bound actions should be all removed after flushing. However,
 	 * filters are destroyed in RCU callbacks, we have to hold the chains
@@ -302,6 +344,14 @@ void tcf_block_put(struct tcf_block *block)
 		tcf_chain_put(chain);
 	kfree(block);
 }
+EXPORT_SYMBOL(tcf_block_put_ext);
+
+void tcf_block_put(struct tcf_block *block)
+{
+	struct tcf_block_ext_info ei = {0, };
+
+	tcf_block_put_ext(block, NULL, block->q, &ei);
+}
 EXPORT_SYMBOL(tcf_block_put);
 
 /* Main classifier routine: scans classifier chain attached