packet_history.h revision 34a9e7ea91bb4acb45ae5331e7403304029329b2 
1/*
2 *  Packet RX/TX history data structures and routines for TFRC-based protocols.
3 *
4 *  Copyright (c) 2007   The University of Aberdeen, Scotland, UK
5 *  Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
6 *
7 *  This code has been developed by the University of Waikato WAND
8 *  research group. For further information please see http://www.wand.net.nz/
9 *  or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz
10 *
11 *  This code also uses code from Lulea University, rereleased as GPL by its
12 *  authors:
13 *  Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
14 *
15 *  Changes to meet Linux coding standards, to make it meet latest ccid3 draft
16 *  and to make it work as a loadable module in the DCCP stack written by
17 *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
18 *
19 *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
20 *
21 *  This program is free software; you can redistribute it and/or modify
22 *  it under the terms of the GNU General Public License as published by
23 *  the Free Software Foundation; either version 2 of the License, or
24 *  (at your option) any later version.
25 *
26 *  This program is distributed in the hope that it will be useful,
27 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
28 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
29 *  GNU General Public License for more details.
30 *
31 *  You should have received a copy of the GNU General Public License
32 *  along with this program; if not, write to the Free Software
33 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
34 */
35
36#ifndef _DCCP_PKT_HIST_
37#define _DCCP_PKT_HIST_
38
39#include <linux/ktime.h>
40#include <linux/list.h>
41#include <linux/slab.h>
42#include "tfrc.h"
43
44/* Number of later packets received before one is considered lost */
45#define TFRC_RECV_NUM_LATE_LOSS	 3
46
47#define TFRC_WIN_COUNT_PER_RTT	 4
48#define TFRC_WIN_COUNT_LIMIT	16
49
50struct tfrc_tx_hist_entry;
51
52extern int  tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
53extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);
54extern u32  tfrc_tx_hist_rtt(struct tfrc_tx_hist_entry *head,
55			     const u64 seqno, const ktime_t now);
56
57/*
58 * 	Receiver History data structures and declarations
59 */
60struct dccp_rx_hist_entry {
61	struct list_head dccphrx_node;
62	u64		 dccphrx_seqno:48,
63			 dccphrx_ccval:4,
64			 dccphrx_type:4;
65	u32		 dccphrx_ndp; /* In fact it is from 8 to 24 bits */
66	ktime_t		 dccphrx_tstamp;
67};
68
69extern struct dccp_rx_hist_entry *
70			dccp_rx_hist_entry_new(const u32 ndp,
71					       const struct sk_buff *skb,
72					       const gfp_t prio);
73
74static inline struct dccp_rx_hist_entry *
75			dccp_rx_hist_head(struct list_head *list)
76{
77	struct dccp_rx_hist_entry *head = NULL;
78
79	if (!list_empty(list))
80		head = list_entry(list->next, struct dccp_rx_hist_entry,
81				  dccphrx_node);
82	return head;
83}
84
85extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
86				   u8 *ccval);
87extern struct dccp_rx_hist_entry *
88		dccp_rx_hist_find_data_packet(const struct list_head *list);
89
90extern void dccp_rx_hist_add_packet(struct list_head *rx_list,
91				    struct list_head *li_list,
92				    struct dccp_rx_hist_entry *packet,
93				    u64 nonloss_seqno);
94
95extern void dccp_rx_hist_purge(struct list_head *list);
96
97static inline int
98	dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
99{
100	return entry->dccphrx_type == DCCP_PKT_DATA ||
101	       entry->dccphrx_type == DCCP_PKT_DATAACK;
102}
103
104extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
105				    struct list_head *li_list, u8 *win_loss);
106
107#endif /* _DCCP_PKT_HIST_ */
108