aboutsummaryrefslogtreecommitdiffstats
path: root/net/dccp/ccids/lib/packet_history.h
blob: 5c07182dd65972ea736bc79fa69493c59dc8dc9f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/*
 *  Packet RX/TX history data structures and routines for TFRC-based protocols.
 *
 *  Copyright (c) 2007   The University of Aberdeen, Scotland, UK
 *  Copyright (c) 2005-6 The University of Waikato, Hamilton, New Zealand.
 *
 *  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 - ian.mcdonald@jandi.co.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.
 */

#ifndef _DCCP_PKT_HIST_
#define _DCCP_PKT_HIST_

#include <linux/ktime.h>
#include <linux/list.h>
#include <linux/slab.h>

#include "../../dccp.h"

/* Number of later packets received before one is considered lost */
#define TFRC_RECV_NUM_LATE_LOSS	 3

#define TFRC_WIN_COUNT_PER_RTT	 4
#define TFRC_WIN_COUNT_LIMIT	16

/**
 *  tfrc_tx_hist_entry  -  Simple singly-linked TX history list
 *  @next:  next oldest entry (LIFO order)
 *  @seqno: sequence number of this entry
 *  @stamp: send time of packet with sequence number @seqno
 */
struct tfrc_tx_hist_entry {
	struct tfrc_tx_hist_entry *next;
	u64			  seqno;
	ktime_t			  stamp;
};

extern int  tfrc_tx_hist_add(struct tfrc_tx_hist_entry **headp, u64 seqno);
extern void tfrc_tx_hist_purge(struct tfrc_tx_hist_entry **headp);

extern struct tfrc_tx_hist_entry *
	tfrc_tx_hist_find_entry(struct tfrc_tx_hist_entry *head, u64 ackno);

/*
 * 	Receiver History data structures and declarations
 */
struct dccp_rx_hist_entry {
	struct list_head dccphrx_node;
	u64		 dccphrx_seqno:48,
			 dccphrx_ccval:4,
			 dccphrx_type:4;
	u32		 dccphrx_ndp; /* In fact it is from 8 to 24 bits */
	ktime_t		 dccphrx_tstamp;
};

struct dccp_rx_hist {
	struct kmem_cache *dccprxh_slab;
};

extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
extern void 		dccp_rx_hist_delete(struct dccp_rx_hist *hist);

static inline struct dccp_rx_hist_entry *
			dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
					       const u32 ndp,
					       const struct sk_buff *skb,
					       const gfp_t prio)
{
	struct dccp_rx_hist_entry *entry = kmem_cache_alloc(hist->dccprxh_slab,
							    prio);

	if (entry != NULL) {
		const struct dccp_hdr *dh = dccp_hdr(skb);

		entry->dccphrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
		entry->dccphrx_ccval = dh->dccph_ccval;
		entry->dccphrx_type  = dh->dccph_type;
		entry->dccphrx_ndp   = ndp;
		entry->dccphrx_tstamp = ktime_get_real();
	}

	return entry;
}

static inline struct dccp_rx_hist_entry *
			dccp_rx_hist_head(struct list_head *list)
{
	struct dccp_rx_hist_entry *head = NULL;

	if (!list_empty(list))
		head = list_entry(list->next, struct dccp_rx_hist_entry,
				  dccphrx_node);
	return head;
}

extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
				   u8 *ccval);
extern struct dccp_rx_hist_entry *
		dccp_rx_hist_find_data_packet(const struct list_head *list);

extern void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
				    struct list_head *rx_list,
				    struct list_head *li_list,
				    struct dccp_rx_hist_entry *packet,
				    u64 nonloss_seqno);

static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist,
					     struct dccp_rx_hist_entry *entry)
{
	if (entry != NULL)
		kmem_cache_free(hist->dccprxh_slab, entry);
}

extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
			       struct list_head *list);

static inline int
	dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
{
	return entry->dccphrx_type == DCCP_PKT_DATA ||
	       entry->dccphrx_type == DCCP_PKT_DATAACK;
}

extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
				    struct list_head *li_list, u8 *win_loss);

#endif /* _DCCP_PKT_HIST_ */