5 files changed, 104 insertions, 26 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index c45ad1263271..2e7405500626 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -179,6 +179,16 @@ enum {
         SKB_GSO_TCPV6 = 1 << 4,
 };
 
+#if BITS_PER_LONG > 32
+#define NET_SKBUFF_DATA_USES_OFFSET 1
+#endif
+
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+typedef unsigned int sk_buff_data_t;
+#else
+typedef unsigned char *sk_buff_data_t;
+#endif
+
 /** 
  *      struct sk_buff - socket buffer
  *      @next: Next buffer in list
@@ -236,9 +246,9 @@ struct sk_buff {
         int                     iif;
         /* 4 byte hole on 64 bit*/
 
-        unsigned char           *transport_header;
-        unsigned char           *network_header;
-        unsigned char           *mac_header;
+        sk_buff_data_t          transport_header;
+        sk_buff_data_t          network_header;
+        sk_buff_data_t          mac_header;
         struct  dst_entry       *dst;
         struct  sec_path        *sp;
 
@@ -942,50 +952,92 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
         skb->tail += len;
 }
 
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
 static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
 {
-        return skb->transport_header;
+        return skb->head + skb->transport_header;
 }
 
 static inline void skb_reset_transport_header(struct sk_buff *skb)
 {
-        skb->transport_header = skb->data;
+        skb->transport_header = skb->data - skb->head;
 }
 
 static inline void skb_set_transport_header(struct sk_buff *skb,
                                             const int offset)
 {
-        skb->transport_header = skb->data + offset;
-}
-
-static inline int skb_transport_offset(const struct sk_buff *skb)
-{
-        return skb->transport_header - skb->data;
+        skb_reset_transport_header(skb);
+        skb->transport_header += offset;
 }
 
 static inline unsigned char *skb_network_header(const struct sk_buff *skb)
 {
-        return skb->network_header;
+        return skb->head + skb->network_header;
 }
 
 static inline void skb_reset_network_header(struct sk_buff *skb)
 {
-        skb->network_header = skb->data;
+        skb->network_header = skb->data - skb->head;
 }
 
 static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
 {
-        skb->network_header = skb->data + offset;
+        skb_reset_network_header(skb);
+        skb->network_header += offset;
 }
 
-static inline int skb_network_offset(const struct sk_buff *skb)
+static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
 {
-        return skb->network_header - skb->data;
+        return skb->head + skb->mac_header;
 }
 
-static inline u32 skb_network_header_len(const struct sk_buff *skb)
+static inline int skb_mac_header_was_set(const struct sk_buff *skb)
 {
-        return skb->transport_header - skb->network_header;
+        return skb->mac_header != ~0U;
+}
+
+static inline void skb_reset_mac_header(struct sk_buff *skb)
+{
+        skb->mac_header = skb->data - skb->head;
+}
+
+static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
+{
+        skb_reset_mac_header(skb);
+        skb->mac_header += offset;
+}
+
+#else /* NET_SKBUFF_DATA_USES_OFFSET */
+
+static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
+{
+        return skb->transport_header;
+}
+
+static inline void skb_reset_transport_header(struct sk_buff *skb)
+{
+        skb->transport_header = skb->data;
+}
+
+static inline void skb_set_transport_header(struct sk_buff *skb,
+                                            const int offset)
+{
+        skb->transport_header = skb->data + offset;
+}
+
+static inline unsigned char *skb_network_header(const struct sk_buff *skb)
+{
+        return skb->network_header;
+}
+
+static inline void skb_reset_network_header(struct sk_buff *skb)
+{
+        skb->network_header = skb->data;
+}
+
+static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
+{
+        skb->network_header = skb->data + offset;
 }
 
 static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
@@ -1007,6 +1059,22 @@ static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
 {
         skb->mac_header = skb->data + offset;
 }
+#endif /* NET_SKBUFF_DATA_USES_OFFSET */
+
+static inline int skb_transport_offset(const struct sk_buff *skb)
+{
+        return skb_transport_header(skb) - skb->data;
+}
+
+static inline u32 skb_network_header_len(const struct sk_buff *skb)
+{
+        return skb->transport_header - skb->network_header;
+}
+
+static inline int skb_network_offset(const struct sk_buff *skb)
+{
+        return skb_network_header(skb) - skb->data;
+}
 
 /*
  * CPUs often take a performance hit when accessing unaligned memory
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 1e71764be4a4..a48b08681261 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -448,11 +448,12 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
 
 static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 {
+#ifndef NET_SKBUFF_DATA_USES_OFFSET
         /*
          *      Shift between the two data areas in bytes
          */
         unsigned long offset = new->data - old->data;
-
+#endif
         new->sk         = NULL;
         new->dev        = old->dev;
         new->priority   = old->priority;
@@ -461,9 +462,15 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 #ifdef CONFIG_INET
         new->sp         = secpath_get(old->sp);
 #endif
-        new->transport_header = old->transport_header + offset;
-        new->network_header   = old->network_header + offset;
-        new->mac_header       = old->mac_header + offset;
+        new->transport_header = old->transport_header;
+        new->network_header   = old->network_header;
+        new->mac_header       = old->mac_header;
+#ifndef NET_SKBUFF_DATA_USES_OFFSET
+        /* {transport,network,mac}_header are relative to skb->head */
+        new->transport_header += offset;
+        new->network_header   += offset;
+        new->mac_header       += offset;
+#endif
         memcpy(new->cb, old->cb, sizeof(old->cb));
         new->local_df   = old->local_df;
         new->fclone     = SKB_FCLONE_UNAVAILABLE;
@@ -639,9 +646,12 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
         skb->end      = data + size;
         skb->data    += off;
         skb->tail    += off;
+#ifndef NET_SKBUFF_DATA_USES_OFFSET
+        /* {transport,network,mac}_header are relative to skb->head */
         skb->transport_header += off;
         skb->network_header   += off;
         skb->mac_header       += off;
+#endif
         skb->cloned   = 0;
         skb->nohdr    = 0;
         atomic_set(&skb_shinfo(skb)->dataref, 1);
diff --git a/net/ipv4/ipvs/ip_vs_xmit.c b/net/ipv4/ipvs/ip_vs_xmit.c
index fded9b2f227c..900ce29db382 100644
--- a/net/ipv4/ipvs/ip_vs_xmit.c
+++ b/net/ipv4/ipvs/ip_vs_xmit.c
@@ -323,7 +323,7 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
         struct iphdr  *old_iph = ip_hdr(skb);
         u8     tos = old_iph->tos;
         __be16 df = old_iph->frag_off;
-        unsigned char *old_transport_header = skb->transport_header;
+        sk_buff_data_t old_transport_header = skb->transport_header;
         struct iphdr  *iph;                     /* Our new IP header */
         int    max_headroom;                    /* The extra header space needed */
         int    mtu;
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 87feee166da9..1ff47b18724a 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -513,7 +513,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info)
         struct sctp_association *asoc = NULL;
         struct sctp_transport *transport;
         struct inet_sock *inet;
-        char *saveip, *savesctp;
+        sk_buff_data_t saveip, savesctp;
         int err;
 
         if (skb->len < ihlen + 8) {
@@ -527,7 +527,7 @@ void sctp_v4_err(struct sk_buff *skb, __u32 info)
         skb_reset_network_header(skb);
         skb_set_transport_header(skb, ihlen);
         sk = sctp_err_lookup(AF_INET, skb, sctp_hdr(skb), &asoc, &transport);
-        /* Put back, the original pointers. */
+        /* Put back, the original values. */
         skb->network_header = saveip;
         skb->transport_header = savesctp;
         if (!sk) {
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index afcb0093c290..5b0cdda4b449 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -126,7 +126,7 @@ SCTP_STATIC void sctp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         struct sctp_association *asoc;
         struct sctp_transport *transport;
         struct ipv6_pinfo *np;
-        char *saveip, *savesctp;
+        sk_buff_data_t saveip, savesctp;
         int err;
 
         idev = in6_dev_get(skb->dev);