packet_history.h revision 0740d49c2465bdd2644455c4bc49794395b73433 
1/*
2 *  net/dccp/packet_history.h
3 *
4 *  Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
5 *
6 *  An implementation of the DCCP protocol
7 *
8 *  This code has been developed by the University of Waikato WAND
9 *  research group. For further information please see http://www.wand.net.nz/
10 *  or e-mail Ian McDonald - ian.mcdonald@jandi.co.nz
11 *
12 *  This code also uses code from Lulea University, rereleased as GPL by its
13 *  authors:
14 *  Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
15 *
16 *  Changes to meet Linux coding standards, to make it meet latest ccid3 draft
17 *  and to make it work as a loadable module in the DCCP stack written by
18 *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
19 *
20 *  Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
21 *
22 *  This program is free software; you can redistribute it and/or modify
23 *  it under the terms of the GNU General Public License as published by
24 *  the Free Software Foundation; either version 2 of the License, or
25 *  (at your option) any later version.
26 *
27 *  This program is distributed in the hope that it will be useful,
28 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
29 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
30 *  GNU General Public License for more details.
31 *
32 *  You should have received a copy of the GNU General Public License
33 *  along with this program; if not, write to the Free Software
34 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
35 */
36
37#ifndef _DCCP_PKT_HIST_
38#define _DCCP_PKT_HIST_
39
40#include <linux/ktime.h>
41#include <linux/list.h>
42#include <linux/slab.h>
43
44#include "../../dccp.h"
45
46/* Number of later packets received before one is considered lost */
47#define TFRC_RECV_NUM_LATE_LOSS	 3
48
49#define TFRC_WIN_COUNT_PER_RTT	 4
50#define TFRC_WIN_COUNT_LIMIT	16
51
52/*
53 * 	Transmitter History data structures and declarations
54 */
55struct dccp_tx_hist_entry {
56	struct list_head dccphtx_node;
57	u64		 dccphtx_seqno:48,
58			 dccphtx_sent:1;
59	u32		 dccphtx_rtt;
60	ktime_t		 dccphtx_tstamp;
61};
62
63struct dccp_tx_hist {
64	struct kmem_cache *dccptxh_slab;
65};
66
67extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
68extern void 		    dccp_tx_hist_delete(struct dccp_tx_hist *hist);
69
70static inline struct dccp_tx_hist_entry *
71			dccp_tx_hist_entry_new(struct dccp_tx_hist *hist,
72					       const gfp_t prio)
73{
74	struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab,
75							    prio);
76
77	if (entry != NULL)
78		entry->dccphtx_sent = 0;
79
80	return entry;
81}
82
83static inline struct dccp_tx_hist_entry *
84			dccp_tx_hist_head(struct list_head *list)
85{
86	struct dccp_tx_hist_entry *head = NULL;
87
88	if (!list_empty(list))
89		head = list_entry(list->next, struct dccp_tx_hist_entry,
90				  dccphtx_node);
91	return head;
92}
93
94extern struct dccp_tx_hist_entry *
95			dccp_tx_hist_find_entry(const struct list_head *list,
96						const u64 seq);
97
98static inline void dccp_tx_hist_add_entry(struct list_head *list,
99					  struct dccp_tx_hist_entry *entry)
100{
101	list_add(&entry->dccphtx_node, list);
102}
103
104static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist,
105					     struct dccp_tx_hist_entry *entry)
106{
107	if (entry != NULL)
108		kmem_cache_free(hist->dccptxh_slab, entry);
109}
110
111extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
112			       struct list_head *list);
113
114extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
115				     struct list_head *list,
116				     struct dccp_tx_hist_entry *next);
117
118/*
119 * 	Receiver History data structures and declarations
120 */
121struct dccp_rx_hist_entry {
122	struct list_head dccphrx_node;
123	u64		 dccphrx_seqno:48,
124			 dccphrx_ccval:4,
125			 dccphrx_type:4;
126	u32		 dccphrx_ndp; /* In fact it is from 8 to 24 bits */
127	ktime_t		 dccphrx_tstamp;
128};
129
130struct dccp_rx_hist {
131	struct kmem_cache *dccprxh_slab;
132};
133
134extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
135extern void 		dccp_rx_hist_delete(struct dccp_rx_hist *hist);
136
137static inline struct dccp_rx_hist_entry *
138			dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
139					       const u32 ndp,
140					       const struct sk_buff *skb,
141					       const gfp_t prio)
142{
143	struct dccp_rx_hist_entry *entry = kmem_cache_alloc(hist->dccprxh_slab,
144							    prio);
145
146	if (entry != NULL) {
147		const struct dccp_hdr *dh = dccp_hdr(skb);
148
149		entry->dccphrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
150		entry->dccphrx_ccval = dh->dccph_ccval;
151		entry->dccphrx_type  = dh->dccph_type;
152		entry->dccphrx_ndp   = ndp;
153		entry->dccphrx_tstamp = ktime_get_real();
154	}
155
156	return entry;
157}
158
159static inline struct dccp_rx_hist_entry *
160			dccp_rx_hist_head(struct list_head *list)
161{
162	struct dccp_rx_hist_entry *head = NULL;
163
164	if (!list_empty(list))
165		head = list_entry(list->next, struct dccp_rx_hist_entry,
166				  dccphrx_node);
167	return head;
168}
169
170extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
171				   u8 *ccval);
172extern struct dccp_rx_hist_entry *
173		dccp_rx_hist_find_data_packet(const struct list_head *list);
174
175extern void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
176				    struct list_head *rx_list,
177				    struct list_head *li_list,
178				    struct dccp_rx_hist_entry *packet,
179				    u64 nonloss_seqno);
180
181static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist,
182					     struct dccp_rx_hist_entry *entry)
183{
184	if (entry != NULL)
185		kmem_cache_free(hist->dccprxh_slab, entry);
186}
187
188extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
189			       struct list_head *list);
190
191static inline int
192	dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
193{
194	return entry->dccphrx_type == DCCP_PKT_DATA ||
195	       entry->dccphrx_type == DCCP_PKT_DATAACK;
196}
197
198extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
199				    struct list_head *li_list, u8 *win_loss);
200
201#endif /* _DCCP_PKT_HIST_ */
202