[PATCH 1/6] [net-next]net: sched: act_mirred: Extend redirect action to accept a traffic class

[Amritha Nambiar <amritha.nambiar@intel.com>]

The Mirred/redirect action is extended to forward to a traffic
class on the device. The traffic class index needs to be
provided in addition to the device's ifindex.

Example:
# tc filter add dev eth0 protocol ip parent ffff: prio 1 flower\
  dst_ip 192.168.1.1/32 ip_proto udp dst_port 22\
  skip_sw indev eth0 action mirred ingress redirect dev eth0 tc 1

Signed-off-by: Amritha Nambiar <amritha.nambiar@intel.com>
---
 include/net/tc_act/tc_mirred.h        |    7 +++++++
 include/uapi/linux/tc_act/tc_mirred.h |    5 +++++
 net/sched/act_mirred.c                |   17 +++++++++++++++++
 3 files changed, 29 insertions(+)

diff --git a/include/net/tc_act/tc_mirred.h b/include/net/tc_act/tc_mirred.h
index 604bc31..60058c4 100644
--- a/include/net/tc_act/tc_mirred.h
+++ b/include/net/tc_act/tc_mirred.h
@@ -9,6 +9,8 @@ struct tcf_mirred {
 	int			tcfm_eaction;
 	int			tcfm_ifindex;
 	bool			tcfm_mac_header_xmit;
+	u8			tcfm_tc;
+	u32			flags;
 	struct net_device __rcu	*tcfm_dev;
 	struct list_head	tcfm_list;
 };
@@ -37,4 +39,9 @@ static inline int tcf_mirred_ifindex(const struct tc_action *a)
 	return to_mirred(a)->tcfm_ifindex;
 }
 
+static inline int tcf_mirred_tc(const struct tc_action *a)
+{
+	return to_mirred(a)->tcfm_tc;
+}
+
 #endif /* __NET_TC_MIR_H */
diff --git a/include/uapi/linux/tc_act/tc_mirred.h b/include/uapi/linux/tc_act/tc_mirred.h
index 3d7a2b3..8ff4d76 100644
--- a/include/uapi/linux/tc_act/tc_mirred.h
+++ b/include/uapi/linux/tc_act/tc_mirred.h
@@ -9,6 +9,10 @@
 #define TCA_EGRESS_MIRROR 2 /* mirror packet to EGRESS */
 #define TCA_INGRESS_REDIR 3  /* packet redirect to INGRESS*/
 #define TCA_INGRESS_MIRROR 4 /* mirror packet to INGRESS */
+
+#define MIRRED_F_TC_MAP		0x1
+#define MIRRED_TC_MAP_MAX	0x10
+#define MIRRED_TC_MAP_MASK	0xF
                                                                                 
 struct tc_mirred {
 	tc_gen;
@@ -21,6 +25,7 @@ enum {
 	TCA_MIRRED_TM,
 	TCA_MIRRED_PARMS,
 	TCA_MIRRED_PAD,
+	TCA_MIRRED_TC_MAP,
 	__TCA_MIRRED_MAX
 };
 #define TCA_MIRRED_MAX (__TCA_MIRRED_MAX - 1)
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 1b5549a..f9801de 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -67,6 +67,7 @@ static void tcf_mirred_release(struct tc_action *a, int bind)
 
 static const struct nla_policy mirred_policy[TCA_MIRRED_MAX + 1] = {
 	[TCA_MIRRED_PARMS]	= { .len = sizeof(struct tc_mirred) },
+	[TCA_MIRRED_TC_MAP]	= { .type = NLA_U8 },
 };
 
 static unsigned int mirred_net_id;
@@ -83,6 +84,8 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	struct tcf_mirred *m;
 	struct net_device *dev;
 	bool exists = false;
+	u8 *tc_map = NULL;
+	u32 flags = 0;
 	int ret;
 
 	if (nla == NULL)
@@ -92,6 +95,14 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 		return ret;
 	if (tb[TCA_MIRRED_PARMS] == NULL)
 		return -EINVAL;
+
+	if (tb[TCA_MIRRED_TC_MAP]) {
+		tc_map = nla_data(tb[TCA_MIRRED_TC_MAP]);
+		if (*tc_map >= MIRRED_TC_MAP_MAX)
+			return -EINVAL;
+		flags |= MIRRED_F_TC_MAP;
+	}
+
 	parm = nla_data(tb[TCA_MIRRED_PARMS]);
 
 	exists = tcf_hash_check(tn, parm->index, a, bind);
@@ -139,6 +150,7 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	ASSERT_RTNL();
 	m->tcf_action = parm->action;
 	m->tcfm_eaction = parm->eaction;
+	m->flags = flags;
 	if (dev != NULL) {
 		m->tcfm_ifindex = parm->ifindex;
 		if (ret != ACT_P_CREATED)
@@ -146,6 +158,8 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 		dev_hold(dev);
 		rcu_assign_pointer(m->tcfm_dev, dev);
 		m->tcfm_mac_header_xmit = mac_header_xmit;
+		if (flags & MIRRED_F_TC_MAP)
+			m->tcfm_tc = *tc_map & MIRRED_TC_MAP_MASK;
 	}
 
 	if (ret == ACT_P_CREATED) {
@@ -259,6 +273,9 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 
 	if (nla_put(skb, TCA_MIRRED_PARMS, sizeof(opt), &opt))
 		goto nla_put_failure;
+	if ((m->flags & MIRRED_F_TC_MAP) &&
+	    nla_put_u8(skb, TCA_MIRRED_TC_MAP, m->tcfm_tc))
+		goto nla_put_failure;
 
 	tcf_tm_dump(&t, &m->tcf_tm);
 	if (nla_put_64bit(skb, TCA_MIRRED_TM, sizeof(t), &t, TCA_MIRRED_PAD))