diff --git a/net/dccp/packet_history.c b/net/dccp/packet_history.c
new file mode 100644
index 0000000..6b41489
--- /dev/null
+++ b/net/dccp/packet_history.c
@@ -0,0 +1,198 @@
+/*
+ *  net/dccp/packet_history.h
+ *
+ *  Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
+ *
+ *  An implementation of the DCCP protocol
+ *
+ *  This code has been developed by the University of Waikato WAND
+ *  research group. For further information please see http://www.wand.net.nz/
+ *  or e-mail Ian McDonald - iam4@cs.waikato.ac.nz
+ *
+ *  This code also uses code from Lulea University, rereleased as GPL by its
+ *  authors:
+ *  Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
+ *
+ *  Changes to meet Linux coding standards, to make it meet latest ccid3 draft
+ *  and to make it work as a loadable module in the DCCP stack written by
+ *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
+ *
+ *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/config.h>
+#include <linux/string.h>
+
+#include "packet_history.h"
+
+struct dccp_rx_hist *dccp_rx_hist_new(const char *name)
+{
+	struct dccp_rx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
+	static const char dccp_rx_hist_mask[] = "rx_hist_%s";
+	char *slab_name;
+
+	if (hist == NULL)
+		goto out;
+
+	slab_name = kmalloc(strlen(name) + sizeof(dccp_rx_hist_mask) - 1,
+			    GFP_ATOMIC);
+	if (slab_name == NULL)
+		goto out_free_hist;
+
+	sprintf(slab_name, dccp_rx_hist_mask, name);
+	hist->dccprxh_slab = kmem_cache_create(slab_name,
+					       sizeof(struct dccp_rx_hist_entry),
+					       0, SLAB_HWCACHE_ALIGN,
+					       NULL, NULL);
+	if (hist->dccprxh_slab == NULL)
+		goto out_free_slab_name;
+out:
+	return hist;
+out_free_slab_name:
+	kfree(slab_name);
+out_free_hist:
+	kfree(hist);
+	hist = NULL;
+	goto out;
+}
+
+EXPORT_SYMBOL_GPL(dccp_rx_hist_new);
+
+void dccp_rx_hist_delete(struct dccp_rx_hist *hist)
+{
+	const char* name = kmem_cache_name(hist->dccprxh_slab);
+
+	kmem_cache_destroy(hist->dccprxh_slab);
+	kfree(name);
+	kfree(hist);
+}
+
+EXPORT_SYMBOL_GPL(dccp_rx_hist_delete);
+
+void dccp_rx_hist_purge(struct dccp_rx_hist *hist, struct list_head *list)
+{
+	struct dccp_rx_hist_entry *entry, *next;
+
+	list_for_each_entry_safe(entry, next, list, dccphrx_node) {
+		list_del_init(&entry->dccphrx_node);
+		kmem_cache_free(hist->dccprxh_slab, entry);
+	}
+}
+
+EXPORT_SYMBOL_GPL(dccp_rx_hist_purge);
+
+struct dccp_rx_hist_entry *
+		dccp_rx_hist_find_data_packet(const struct list_head *list)
+{
+	struct dccp_rx_hist_entry *entry, *packet = NULL;
+
+	list_for_each_entry(entry, list, dccphrx_node)
+		if (entry->dccphrx_type == DCCP_PKT_DATA ||
+		    entry->dccphrx_type == DCCP_PKT_DATAACK) {
+			packet = entry;
+			break;
+		}
+
+	return packet;
+}
+
+EXPORT_SYMBOL_GPL(dccp_rx_hist_find_data_packet);
+
+struct dccp_tx_hist *dccp_tx_hist_new(const char *name)
+{
+	struct dccp_tx_hist *hist = kmalloc(sizeof(*hist), GFP_ATOMIC);
+	static const char dccp_tx_hist_mask[] = "tx_hist_%s";
+	char *slab_name;
+
+	if (hist == NULL)
+		goto out;
+
+	slab_name = kmalloc(strlen(name) + sizeof(dccp_tx_hist_mask) - 1,
+			    GFP_ATOMIC);
+	if (slab_name == NULL)
+		goto out_free_hist;
+
+	sprintf(slab_name, dccp_tx_hist_mask, name);
+	hist->dccptxh_slab = kmem_cache_create(slab_name,
+					       sizeof(struct dccp_tx_hist_entry),
+					       0, SLAB_HWCACHE_ALIGN,
+					       NULL, NULL);
+	if (hist->dccptxh_slab == NULL)
+		goto out_free_slab_name;
+out:
+	return hist;
+out_free_slab_name:
+	kfree(slab_name);
+out_free_hist:
+	kfree(hist);
+	hist = NULL;
+	goto out;
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_new);
+
+void dccp_tx_hist_delete(struct dccp_tx_hist *hist)
+{
+	const char* name = kmem_cache_name(hist->dccptxh_slab);
+
+	kmem_cache_destroy(hist->dccptxh_slab);
+	kfree(name);
+	kfree(hist);
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_delete);
+
+struct dccp_tx_hist_entry *dccp_tx_hist_find_entry(const struct list_head *list,
+						   const u64 seq)
+{
+	struct dccp_tx_hist_entry *packet = NULL, *entry;
+
+	list_for_each_entry(entry, list, dccphtx_node)
+		if (entry->dccphtx_seqno == seq) {
+			packet = entry;
+			break;
+		}
+
+	return packet;
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_find_entry);
+
+void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist, struct list_head *list,
+			      struct dccp_tx_hist_entry *packet)
+{
+	struct dccp_tx_hist_entry *next;
+
+	list_for_each_entry_safe_continue(packet, next, list, dccphtx_node) {
+		list_del_init(&packet->dccphtx_node);
+		dccp_tx_hist_entry_delete(hist, packet);
+	}
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_purge_older);
+
+void dccp_tx_hist_purge(struct dccp_tx_hist *hist, struct list_head *list)
+{
+	struct dccp_tx_hist_entry *entry, *next;
+
+	list_for_each_entry_safe(entry, next, list, dccphtx_node) {
+		list_del_init(&entry->dccphtx_node);
+		dccp_tx_hist_entry_delete(hist, entry);
+	}
+}
+
+EXPORT_SYMBOL_GPL(dccp_tx_hist_purge);