[patch net-next v8 08/14] net: sched: add rt netlink message type for block get

@@ -150,6 +150,12 @@ enum {
 	RTM_NEWCACHEREPORT = 96,
 #define RTM_NEWCACHEREPORT RTM_NEWCACHEREPORT
 
+	RTM_NEWBLOCK = 100,
+#define RTM_NEWBLOCK RTM_NEWBLOCK
+	RTM_DELBLOCK,
+#define RTM_DELBLOCK RTM_DELBLOCK
+	RTM_GETBLOCK,
+#define RTM_GETBLOCK RTM_GETBLOCK
 	__RTM_MAX,
 #define RTM_MAX		(((__RTM_MAX + 3) & ~3) - 1)
 };

@@ -1553,6 +1553,69 @@ int tc_setup_cb_call(struct tcf_block *block, struct tcf_exts *exts,
 }
 EXPORT_SYMBOL(tc_setup_cb_call);
 
+static int block_notify_fill(struct net *net, struct sk_buff *skb,
+			     struct tcf_block *block, u32 portid, u32 seq,
+			     u16 flags, int event)
+{
+	struct nlmsghdr *nlh;
+	struct tcmsg *tcm;
+
+	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*tcm), flags);
+	if (!nlh)
+		return -EMSGSIZE;
+	tcm = nlmsg_data(nlh);
+	memset(tcm, 0, sizeof(*tcm));
+	tcm->tcm_family = AF_UNSPEC;
+	tcm->tcm_ifindex = TCM_IFINDEX_MAGIC_BLOCK;
+	tcm->tcm_block_index = block->index;
+	return 0;
+}
+
+static int block_notify(struct net *net, struct sk_buff *oskb,
+			struct nlmsghdr *n, struct tcf_block *block, int event)
+{
+	u32 portid = NETLINK_CB(oskb).portid;
+	struct sk_buff *skb;
+	int err;
+
+	skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb)
+		return -ENOBUFS;
+
+	err = block_notify_fill(net, skb, block, portid,
+				n->nlmsg_seq, n->nlmsg_flags, event);
+	if (err) {
+		kfree_skb(skb);
+		return err;
+	}
+
+	return netlink_unicast(net->rtnl, skb, portid, MSG_DONTWAIT);
+}
+
+static int tc_ctl_block(struct sk_buff *skb, struct nlmsghdr *n,
+			struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(skb->sk);
+	struct tcf_block *block;
+	struct tcmsg *tcm;
+
+	if (n->nlmsg_len < nlmsg_msg_size(sizeof(*tcm)))
+		return -EINVAL;
+
+	tcm = nlmsg_data(n);
+
+	if (tcm->tcm_ifindex != TCM_IFINDEX_MAGIC_BLOCK)
+		return -EINVAL;
+
+	block = tcf_block_lookup(net, tcm->tcm_block_index);
+	if (!block) {
+		NL_SET_ERR_MSG(extack, "Block with the given index does not exist");
+		return -EINVAL;
+	}
+
+	return block_notify(net, skb, n, block, RTM_NEWBLOCK);
+}
+
 static __net_init int tcf_net_init(struct net *net)
 {
 	struct tcf_net *tn = net_generic(net, tcf_net_id);

@@ -1591,6 +1654,7 @@ static int __init tc_filter_init(void)
 	rtnl_register(PF_UNSPEC, RTM_DELTFILTER, tc_ctl_tfilter, NULL, 0);
 	rtnl_register(PF_UNSPEC, RTM_GETTFILTER, tc_ctl_tfilter,
 		      tc_dump_tfilter, 0);
+	rtnl_register(PF_UNSPEC, RTM_GETBLOCK, tc_ctl_block, NULL, 0);
 
 	return 0;
 }

@@ -80,6 +80,9 @@ static const struct nlmsg_perm nlmsg_route_perms[] =
 	{ RTM_NEWSTATS,		NETLINK_ROUTE_SOCKET__NLMSG_READ },
 	{ RTM_GETSTATS,		NETLINK_ROUTE_SOCKET__NLMSG_READ  },
 	{ RTM_NEWCACHEREPORT,	NETLINK_ROUTE_SOCKET__NLMSG_READ },
+	{ RTM_NEWBLOCK,		NETLINK_ROUTE_SOCKET__NLMSG_READ },
+	{ RTM_DELBLOCK,		NETLINK_ROUTE_SOCKET__NLMSG_READ },
+	{ RTM_GETBLOCK,		NETLINK_ROUTE_SOCKET__NLMSG_READ },
 };
 
 static const struct nlmsg_perm nlmsg_tcpdiag_perms[] =

@@ -159,7 +162,7 @@ int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
 	switch (sclass) {
 	case SECCLASS_NETLINK_ROUTE_SOCKET:
 		/* RTM_MAX always point to RTM_SETxxxx, ie RTM_NEWxxx + 3 */
-		BUILD_BUG_ON(RTM_MAX != (RTM_NEWCACHEREPORT + 3));
+		BUILD_BUG_ON(RTM_MAX != (RTM_NEWBLOCK + 3));
 		err = nlmsg_perm(nlmsg_type, perm, nlmsg_route_perms,
 				 sizeof(nlmsg_route_perms));
 		break;