[SK_BUFF]: Convert skb->end to sk_buff_data_t

Now to convert the last one, skb->data, that will allow many simplifications
and removal of some of the offset helpers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 18 deletions

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index ddcbc4d10dab..a203bedefe09 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -87,9 +87,9 @@ static struct kmem_cache *skbuff_fclone_cache __read_mostly;
 void skb_over_panic(struct sk_buff *skb, int sz, void *here)
 {
         printk(KERN_EMERG "skb_over_panic: text:%p len:%d put:%d head:%p "
-                          "data:%p tail:%#lx end:%p dev:%s\n",
+                          "data:%p tail:%#lx end:%#lx dev:%s\n",
                here, skb->len, sz, skb->head, skb->data,
-               (unsigned long)skb->tail, skb->end,
+               (unsigned long)skb->tail, (unsigned long)skb->end,
                skb->dev ? skb->dev->name : "<NULL>");
         BUG();
 }
@@ -106,9 +106,9 @@ void skb_over_panic(struct sk_buff *skb, int sz, void *here)
 void skb_under_panic(struct sk_buff *skb, int sz, void *here)
 {
         printk(KERN_EMERG "skb_under_panic: text:%p len:%d put:%d head:%p "
-                          "data:%p tail:%#lx end:%p dev:%s\n",
+                          "data:%p tail:%#lx end:%#lx dev:%s\n",
                here, skb->len, sz, skb->head, skb->data,
-               (unsigned long)skb->tail, skb->end,
+               (unsigned long)skb->tail, (unsigned long)skb->end,
                skb->dev ? skb->dev->name : "<NULL>");
         BUG();
 }
@@ -170,7 +170,7 @@ struct sk_buff *__alloc_skb(unsigned int size, gfp_t gfp_mask,
         skb->head = data;
         skb->data = data;
         skb_reset_tail_pointer(skb);
-        skb->end  = data + size;
+        skb->end = skb->tail + size;
         /* make sure we initialize shinfo sequentially */
         shinfo = skb_shinfo(skb);
         atomic_set(&shinfo->dataref, 1);
@@ -520,8 +520,12 @@ struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask)
         /*
          *      Allocate the copy buffer
          */
-        struct sk_buff *n = alloc_skb(skb->end - skb->head + skb->data_len,
-                                      gfp_mask);
+        struct sk_buff *n;
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+        n = alloc_skb(skb->end + skb->data_len, gfp_mask);
+#else
+        n = alloc_skb(skb->end - skb->head + skb->data_len, gfp_mask);
+#endif
         if (!n)
                 return NULL;
 
@@ -558,8 +562,12 @@ struct sk_buff *pskb_copy(struct sk_buff *skb, gfp_t gfp_mask)
         /*
          *      Allocate the copy buffer
          */
-        struct sk_buff *n = alloc_skb(skb->end - skb->head, gfp_mask);
-
+        struct sk_buff *n;
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+        n = alloc_skb(skb->end, gfp_mask);
+#else
+        n = alloc_skb(skb->end - skb->head, gfp_mask);
+#endif
         if (!n)
                 goto out;
 
@@ -617,7 +625,11 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
 {
         int i;
         u8 *data;
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+        int size = nhead + skb->end + ntail;
+#else
         int size = nhead + (skb->end - skb->head) + ntail;
+#endif
         long off;
 
         if (skb_shared(skb))
@@ -632,12 +644,13 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
         /* Copy only real data... and, alas, header. This should be
          * optimized for the cases when header is void. */
         memcpy(data + nhead, skb->head,
-                skb->tail
-#ifndef NET_SKBUFF_DATA_USES_OFFSET
-                - skb->head
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+                skb->tail);
+#else
+                skb->tail - skb->head);
 #endif
-                );
-        memcpy(data + size, skb->end, sizeof(struct skb_shared_info));
+        memcpy(data + size, skb_end_pointer(skb),
+               sizeof(struct skb_shared_info));
 
         for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
                 get_page(skb_shinfo(skb)->frags[i].page);
@@ -650,9 +663,11 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
         off = (data + nhead) - skb->head;
 
         skb->head     = data;
-        skb->end      = data + size;
         skb->data    += off;
-#ifndef NET_SKBUFF_DATA_USES_OFFSET
+#ifdef NET_SKBUFF_DATA_USES_OFFSET
+        skb->end      = size;
+#else
+        skb->end      = skb->head + size;
         /* {transport,network,mac}_header and tail are relative to skb->head */
         skb->tail             += off;
         skb->transport_header += off;
@@ -769,7 +784,7 @@ int skb_pad(struct sk_buff *skb, int pad)
                 return 0;
         }
 
-        ntail = skb->data_len + pad - (skb->end - skb_tail_pointer(skb));
+        ntail = skb->data_len + pad - (skb->end - skb->tail);
         if (likely(skb_cloned(skb) || ntail > 0)) {
                 err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC);
                 if (unlikely(err))
@@ -907,7 +922,7 @@ unsigned char *__pskb_pull_tail(struct sk_buff *skb, int delta)
          * plus 128 bytes for future expansions. If we have enough
          * room at tail, reallocate without expansion only if skb is cloned.
          */
-        int i, k, eat = (skb_tail_pointer(skb) + delta) - skb->end;
+        int i, k, eat = (skb->tail + delta) - skb->end;
 
         if (eat > 0 || skb_cloned(skb)) {
                 if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0,