Merge branch 'net-tc-indirect-block-relay'

John Hurley says:

====================
Ensure egress un/bind are relayed with indirect blocks

On register and unregister for indirect blocks, a command is called that
sends a bind/unbind event to the registering driver. This command assumes
that the bind to indirect block will be on ingress. However, drivers such
as NFP have allowed binding to clsact qdiscs as well as ingress qdiscs
from mainline Linux 5.2. A clsact qdisc binds to an ingress and an egress
block.

Rather than assuming that an indirect bind is always ingress, modify the
function names to remove the ingress tag (patch 1). In cls_api, which is
used by NFP to offload TC flower, generate bind/unbind message for both
ingress and egress blocks on the event of indirectly
registering/unregistering from that block. Doing so mimics the behaviour
of both ingress and clsact qdiscs on initialise and destroy.

This now ensures that drivers such as NFP receive the correct binder type
for the indirect block registration.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 19 deletions

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 20d60b8fcb70..3c335fd9bcb0 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -626,15 +626,15 @@ static void tcf_chain_flush(struct tcf_chain *chain, bool rtnl_held)
 static int tcf_block_setup(struct tcf_block *block,
 			   struct flow_block_offload *bo);
 
-static void tc_indr_block_ing_cmd(struct net_device *dev,
-				  struct tcf_block *block,
-				  flow_indr_block_bind_cb_t *cb,
-				  void *cb_priv,
-				  enum flow_block_command command)
+static void tc_indr_block_cmd(struct net_device *dev, struct tcf_block *block,
+			      flow_indr_block_bind_cb_t *cb, void *cb_priv,
+			      enum flow_block_command command, bool ingress)
 {
 	struct flow_block_offload bo = {
 		.command	= command,
-		.binder_type	= FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS,
+		.binder_type	= ingress ?
+				  FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS :
+				  FLOW_BLOCK_BINDER_TYPE_CLSACT_EGRESS,
 		.net		= dev_net(dev),
 		.block_shared	= tcf_block_non_null_shared(block),
 	};
@@ -652,9 +652,10 @@ static void tc_indr_block_ing_cmd(struct net_device *dev,
 	up_write(&block->cb_lock);
 }
 
-static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
+static struct tcf_block *tc_dev_block(struct net_device *dev, bool ingress)
 {
 	const struct Qdisc_class_ops *cops;
+	const struct Qdisc_ops *ops;
 	struct Qdisc *qdisc;
 
 	if (!dev_ingress_queue(dev))
@@ -664,24 +665,37 @@ static struct tcf_block *tc_dev_ingress_block(struct net_device *dev)
 	if (!qdisc)
 		return NULL;
 
-	cops = qdisc->ops->cl_ops;
+	ops = qdisc->ops;
+	if (!ops)
+		return NULL;
+
+	if (!ingress && !strcmp("ingress", ops->id))
+		return NULL;
+
+	cops = ops->cl_ops;
 	if (!cops)
 		return NULL;
 
 	if (!cops->tcf_block)
 		return NULL;
 
-	return cops->tcf_block(qdisc, TC_H_MIN_INGRESS, NULL);
+	return cops->tcf_block(qdisc,
+			       ingress ? TC_H_MIN_INGRESS : TC_H_MIN_EGRESS,
+			       NULL);
 }
 
-static void tc_indr_block_get_and_ing_cmd(struct net_device *dev,
-					  flow_indr_block_bind_cb_t *cb,
-					  void *cb_priv,
-					  enum flow_block_command command)
+static void tc_indr_block_get_and_cmd(struct net_device *dev,
+				      flow_indr_block_bind_cb_t *cb,
+				      void *cb_priv,
+				      enum flow_block_command command)
 {
-	struct tcf_block *block = tc_dev_ingress_block(dev);
+	struct tcf_block *block;
+
+	block = tc_dev_block(dev, true);
+	tc_indr_block_cmd(dev, block, cb, cb_priv, command, true);
 
-	tc_indr_block_ing_cmd(dev, block, cb, cb_priv, command);
+	block = tc_dev_block(dev, false);
+	tc_indr_block_cmd(dev, block, cb, cb_priv, command, false);
 }
 
 static void tc_indr_block_call(struct tcf_block *block,
@@ -3626,9 +3640,9 @@ static struct pernet_operations tcf_net_ops = {
 	.size = sizeof(struct tcf_net),
 };
 
-static struct flow_indr_block_ing_entry block_ing_entry = {
-	.cb = tc_indr_block_get_and_ing_cmd,
-	.list = LIST_HEAD_INIT(block_ing_entry.list),
+static struct flow_indr_block_entry block_entry = {
+	.cb = tc_indr_block_get_and_cmd,
+	.list = LIST_HEAD_INIT(block_entry.list),
 };
 
 static int __init tc_filter_init(void)
@@ -3643,7 +3657,7 @@ static int __init tc_filter_init(void)
 	if (err)
 		goto err_register_pernet_subsys;
 
-	flow_indr_add_block_ing_cb(&block_ing_entry);
+	flow_indr_add_block_cb(&block_entry);
 
 	rtnl_register(PF_UNSPEC, RTM_NEWTFILTER, tc_new_tfilter, NULL,
 		      RTNL_FLAG_DOIT_UNLOCKED);