vserver 1.9.3

[linux-2.6.git] / include / net / inet_ecn.h

diff --git a/include/net/inet_ecn.h b/include/net/inet_ecn.h
index 55dc2b3..f87845e 100644 (file)
--- a/include/net/inet_ecn.h
+++ b/include/net/inet_ecn.h
@@ -2,67 +2,107 @@
 #define _INET_ECN_H_
 
 #include <linux/ip.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&3) == 3;
+       return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
 }
 
-static inline int INET_ECN_is_not_ce(__u8 dsfield)
+static inline int INET_ECN_is_not_ect(__u8 dsfield)
 {
-       return (dsfield&3) == 2;
+       return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
 }
 
 static inline int INET_ECN_is_capable(__u8 dsfield)
 {
-       return (dsfield&2);
+       return (dsfield & INET_ECN_ECT_0);
 }
 
 static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
 {
-       outer &= ~3;
-       if (INET_ECN_is_capable(inner))
-               outer |= (inner & 3);
+       outer &= ~INET_ECN_MASK;
+       outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
+                                         INET_ECN_ECT_0;
        return outer;
 }
 
-#define        INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= 2; } while (0)
-#define        INET_ECN_dontxmit(sk) do { inet_sk(sk)->tos &= ~3; } while (0)
+#define        INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= INET_ECN_ECT_0; } while (0)
+#define        INET_ECN_dontxmit(sk) \
+       do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
 
-#define IP6_ECN_flow_init(label) do {  \
-      (label) &= ~htonl(3<<20);                \
+#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(inet_sk(sk)->tos))              \
-               (label) |= __constant_htons(2 << 4);            \
+#define        IP6_ECN_flow_xmit(sk, label) do {                               \
+       if (INET_ECN_is_capable(inet_sk(sk)->tos))                      \
+               (label) |= __constant_htons(INET_ECN_ECT_0 << 4);       \
     } while (0)
 
 static inline void IP_ECN_set_ce(struct iphdr *iph)
 {
        u32 check = iph->check;
-       check += __constant_htons(0xFFFE);
+       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;
+
+       /*
+        * The following gives us:
+        * INET_ECN_ECT_1 => check += htons(0xFFFD)
+        * INET_ECN_ECT_0 => check += htons(0xFFFE)
+        */
+       check += htons(0xFFFB) + htons(ecn);
+
        iph->check = check + (check>=0xFFFF);
-       iph->tos |= 1;
+       iph->tos |= INET_ECN_CE;
 }
 
 static inline void IP_ECN_clear(struct iphdr *iph)
 {
-       iph->tos &= ~3;
+       iph->tos &= ~INET_ECN_MASK;
+}
+
+static inline void ipv4_copy_dscp(struct iphdr *outer, struct iphdr *inner)
+{
+       u32 dscp = ipv4_get_dsfield(outer) & ~INET_ECN_MASK;
+       ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
 }
 
 struct ipv6hdr;
 
 static inline void IP6_ECN_set_ce(struct ipv6hdr *iph)
 {
-       *(u32*)iph |= htonl(1<<20);
+       if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
+               return;
+       *(u32*)iph |= htonl(INET_ECN_CE << 20);
 }
 
 static inline void IP6_ECN_clear(struct ipv6hdr *iph)
 {
-       *(u32*)iph &= ~htonl(3<<20);
+       *(u32*)iph &= ~htonl(INET_ECN_MASK << 20);
 }
 
-#define ip6_get_dsfield(iph) ((ntohs(*(u16*)(iph)) >> 4) & 0xFF)
+static inline void ipv6_copy_dscp(struct ipv6hdr *outer, struct ipv6hdr *inner)
+{
+       u32 dscp = ipv6_get_dsfield(outer) & ~INET_ECN_MASK;
+       ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
+}
 
 #endif