===== include/linux/tcp.h 1.34 vs edited =====
--- 1.34/include/linux/tcp.h	2005-01-17 14:09:33 -08:00
+++ edited/include/linux/tcp.h	2005-01-31 16:03:32 -08:00
@@ -262,6 +262,7 @@
 	__u32	pmtu_cookie;	/* Last pmtu seen by socket		*/
 	__u32	mss_cache;	/* Cached effective mss, not including SACKS */
 	__u16	mss_cache_std;	/* Like mss_cache, but without TSO */
+	__u16	tso_goal;	/* TSO packet count goal, 1 w/non-TSO paths */
 	__u16	mss_clamp;	/* Maximal mss, negotiated at connection setup */
 	__u16	ext_header_len;	/* Network protocol overhead (IP/IPv6 options) */
 	__u16	ext2_header_len;/* Options depending on route */
===== net/ipv4/tcp_output.c 1.77 vs edited =====
--- 1.77/net/ipv4/tcp_output.c	2005-01-18 12:23:36 -08:00
+++ edited/net/ipv4/tcp_output.c	2005-02-01 14:32:46 -08:00
@@ -707,15 +707,103 @@
 		if (factor > limit)
 			factor = limit;
 
-		tp->mss_cache = mss_now * factor;
+		/* If this ever triggers, change tp->tso_goal to
+		 * a larger type and update this bug check.
+		 */
+		BUG_ON(factor > 65535);
 
-		mss_now = tp->mss_cache;
-	}
+		tp->tso_goal = factor;
+	} else
+		tp->tso_goal = 1;
 
 	if (tp->eff_sacks)
 		mss_now -= (TCPOLEN_SACK_BASE_ALIGNED +
 			    (tp->eff_sacks * TCPOLEN_SACK_PERBLOCK));
 	return mss_now;
+}
+
+static inline int tcp_skb_data_all_paged(struct sk_buff *skb)
+{
+	return skb_headlen(skb) == 0;
+}
+
+/* If possible, append paged data of SRC_SKB onto the
+ * tail of DST_SKB.
+ */
+static int skb_append_pages(struct sk_buff *dst_skb, struct sk_buff *src_skb)
+{
+	int i;
+
+	if (!tcp_skb_data_all_paged(src_skb))
+		return -EINVAL;
+
+	for (i = 0; i < skb_shinfo(src_skb)->nr_frags; i++) {
+		skb_frag_t *src_frag = &skb_shinfo(src_skb)->frags[i];
+		skb_frag_t *dst_frag;
+		int dst_frag_idx;
+
+		dst_frag_idx = skb_shinfo(dst_skb)->nr_frags;
+
+		if (skb_can_coalesce(dst_skb, dst_frag_idx,
+				     src_frag->page, src_frag->page_offset)) {
+			dst_frag = &skb_shinfo(dst_skb)->frags[dst_frag_idx-1];
+			dst_frag->size += src_frag->size;
+		} else {
+			if (dst_frag_idx >= MAX_SKB_FRAGS)
+				return -EMSGSIZE;
+
+			dst_frag = &skb_shinfo(dst_skb)->frags[dst_frag_idx];
+			skb_shinfo(dst_skb)->nr_frags = dst_frag_idx + 1;
+
+			dst_frag->page = src_frag->page;
+			get_page(src_frag->page);
+
+			dst_frag->page_offset = src_frag->page_offset;
+			dst_frag->size = src_frag->size;
+		}
+		dst_skb->data_len += src_frag->size;
+	}
+
+	return 0;
+}
+
+static struct sk_buff *tcp_tso_build(struct sk_buff *head, int mss, int num)
+{
+	struct sk_buff *skb;
+	struct sock *sk;
+	int err;
+
+	sk = head->sk;
+	skb = alloc_skb(sk->sk_prot->max_header, GFP_ATOMIC);
+	err = -ENOMEM;
+	if (!skb)
+		goto fail;
+
+	err = 0;
+	skb_shinfo(skb)->tso_size = mss;
+	skb_shinfo(skb)->tso_segs = num;
+	while (num--) {
+		err = skb_append_pages(skb, head);
+		if (err)
+			goto fail;
+
+		head = head->next;
+	}
+	return skb;
+
+fail:
+	if (skb) {
+		int i;
+
+		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+
+			put_page(frag->page);
+		}
+
+		kfree_skb(skb);
+	}
+	return NULL;
 }
 
 /* This routine writes packets to the network.  It advances the