zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/include/net/inet_ecn.h b/ap/os/linux/linux-3.4.x/include/net/inet_ecn.h
new file mode 100644
index 0000000..2fa1469
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/include/net/inet_ecn.h
@@ -0,0 +1,148 @@
+#ifndef _INET_ECN_H_
+#define _INET_ECN_H_
+
+#include <linux/ip.h>
+#include <linux/skbuff.h>
+
+#include <net/inet_sock.h>
+#include <net/dsfield.h>
+
+enum {
+	INET_ECN_NOT_ECT = 0,
+	INET_ECN_ECT_1 = 1,
+	INET_ECN_ECT_0 = 2,
+	INET_ECN_CE = 3,
+	INET_ECN_MASK = 3,
+};
+
+static inline int INET_ECN_is_ce(__u8 dsfield)
+{
+	return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
+}
+
+static inline int INET_ECN_is_not_ect(__u8 dsfield)
+{
+	return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
+}
+
+static inline int INET_ECN_is_capable(__u8 dsfield)
+{
+	return dsfield & INET_ECN_ECT_0;
+}
+
+/*
+ * RFC 3168 9.1.1
+ *  The full-functionality option for ECN encapsulation is to copy the
+ *  ECN codepoint of the inside header to the outside header on
+ *  encapsulation if the inside header is not-ECT or ECT, and to set the
+ *  ECN codepoint of the outside header to ECT(0) if the ECN codepoint of
+ *  the inside header is CE.
+ */
+static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
+{
+	outer &= ~INET_ECN_MASK;
+	outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
+					  INET_ECN_ECT_0;
+	return outer;
+}
+
+static inline void INET_ECN_xmit(struct sock *sk)
+{
+	inet_sk(sk)->tos |= INET_ECN_ECT_0;
+	if (inet6_sk(sk) != NULL)
+		inet6_sk(sk)->tclass |= INET_ECN_ECT_0;
+}
+
+static inline void INET_ECN_dontxmit(struct sock *sk)
+{
+	inet_sk(sk)->tos &= ~INET_ECN_MASK;
+	if (inet6_sk(sk) != NULL)
+		inet6_sk(sk)->tclass &= ~INET_ECN_MASK;
+}
+
+#define IP6_ECN_flow_init(label) do {		\
+      (label) &= ~htonl(INET_ECN_MASK << 20);	\
+    } while (0)
+
+#define	IP6_ECN_flow_xmit(sk, label) do {				\
+	if (INET_ECN_is_capable(inet6_sk(sk)->tclass))			\
+		(label) |= htonl(INET_ECN_ECT_0 << 20);			\
+    } while (0)
+
+static inline int IP_ECN_set_ce(struct iphdr *iph)
+{
+	u32 check = (__force u32)iph->check;
+	u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
+
+	/*
+	 * After the last operation we have (in binary):
+	 * INET_ECN_NOT_ECT => 01
+	 * INET_ECN_ECT_1   => 10
+	 * INET_ECN_ECT_0   => 11
+	 * INET_ECN_CE      => 00
+	 */
+	if (!(ecn & 2))
+		return !ecn;
+
+	/*
+	 * The following gives us:
+	 * INET_ECN_ECT_1 => check += htons(0xFFFD)
+	 * INET_ECN_ECT_0 => check += htons(0xFFFE)
+	 */
+	check += (__force u16)htons(0xFFFB) + (__force u16)htons(ecn);
+
+	iph->check = (__force __sum16)(check + (check>=0xFFFF));
+	iph->tos |= INET_ECN_CE;
+	return 1;
+}
+
+static inline void IP_ECN_clear(struct iphdr *iph)
+{
+	iph->tos &= ~INET_ECN_MASK;
+}
+
+static inline void ipv4_copy_dscp(unsigned int dscp, struct iphdr *inner)
+{
+	dscp &= ~INET_ECN_MASK;
+	ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
+}
+
+struct ipv6hdr;
+
+static inline int IP6_ECN_set_ce(struct ipv6hdr *iph)
+{
+	if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
+		return 0;
+	*(__be32*)iph |= htonl(INET_ECN_CE << 20);
+	return 1;
+}
+
+static inline void IP6_ECN_clear(struct ipv6hdr *iph)
+{
+	*(__be32*)iph &= ~htonl(INET_ECN_MASK << 20);
+}
+
+static inline void ipv6_copy_dscp(unsigned int dscp, struct ipv6hdr *inner)
+{
+	dscp &= ~INET_ECN_MASK;
+	ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
+}
+
+static inline int INET_ECN_set_ce(struct sk_buff *skb)
+{
+	switch (skb->protocol) {
+	case cpu_to_be16(ETH_P_IP):
+		if (skb->network_header + sizeof(struct iphdr) <= skb->tail)
+			return IP_ECN_set_ce(ip_hdr(skb));
+		break;
+
+	case cpu_to_be16(ETH_P_IPV6):
+		if (skb->network_header + sizeof(struct ipv6hdr) <= skb->tail)
+			return IP6_ECN_set_ce(ipv6_hdr(skb));
+		break;
+	}
+
+	return 0;
+}
+
+#endif