net/dccp/ccids/lib/packet_history.h

   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/list.h>
  41 #include <linux/slab.h>
  42 #include <linux/time.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 struct dccp_tx_hist_entry {
  53         struct list_head dccphtx_node;
  54         u64              dccphtx_seqno:48,
  55                          dccphtx_ccval:4,
  56                          dccphtx_sent:1;
  57         u32              dccphtx_rtt;
  58         struct timeval   dccphtx_tstamp;
  59 };
  60
  61 struct dccp_rx_hist_entry {
  62         struct list_head dccphrx_node;
  63         u64              dccphrx_seqno:48,
  64                          dccphrx_ccval:4,
  65                          dccphrx_type:4;
  66         u32              dccphrx_ndp; /* In fact it is from 8 to 24 bits */
  67         struct timeval   dccphrx_tstamp;
  68 };
  69
  70 struct dccp_tx_hist {
  71         kmem_cache_t *dccptxh_slab;
  72 };
  73
  74 extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
  75 extern void dccp_tx_hist_delete(struct dccp_tx_hist *hist);
  76
  77 struct dccp_rx_hist {
  78         kmem_cache_t *dccprxh_slab;
  79 };
  80
  81 extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
  82 extern void dccp_rx_hist_delete(struct dccp_rx_hist *hist);
  83 extern struct dccp_rx_hist_entry *
  84                 dccp_rx_hist_find_data_packet(const struct list_head *list);
  85
  86 static inline struct dccp_tx_hist_entry *
  87                 dccp_tx_hist_entry_new(struct dccp_tx_hist *hist,
  88                                        const gfp_t prio)
  89 {
  90         struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab,
  91                                                             prio);
  92
  93         if (entry != NULL)
  94                 entry->dccphtx_sent = 0;
  95
  96         return entry;
  97 }
  98
  99 static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist,
 100                                              struct dccp_tx_hist_entry *entry)
 101 {
 102         if (entry != NULL)
 103                 kmem_cache_free(hist->dccptxh_slab, entry);
 104 }
 105
 106 extern struct dccp_tx_hist_entry *
 107                         dccp_tx_hist_find_entry(const struct list_head *list,
 108                                                 const u64 seq);
 109 extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
 110    u8 *ccval);
 111
 112 static inline void dccp_tx_hist_add_entry(struct list_head *list,
 113                                           struct dccp_tx_hist_entry *entry)
 114 {
 115         list_add(&entry->dccphtx_node, list);
 116 }
 117
 118 extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
 119                                      struct list_head *list,
 120                                      struct dccp_tx_hist_entry *next);
 121
 122 extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
 123                                struct list_head *list);
 124
 125 static inline struct dccp_tx_hist_entry *
 126                 dccp_tx_hist_head(struct list_head *list)
 127 {
 128         struct dccp_tx_hist_entry *head = NULL;
 129
 130         if (!list_empty(list))
 131                 head = list_entry(list->next, struct dccp_tx_hist_entry,
 132                                   dccphtx_node);
 133         return head;
 134 }
 135
 136 static inline struct dccp_rx_hist_entry *
 137                      dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
 138                                             const struct sock *sk,
 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                 dccp_timestamp(sk, &entry->dccphrx_tstamp);
 154         }
 155
 156         return entry;
 157 }
 158
 159 static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist,
 160                                              struct dccp_rx_hist_entry *entry)
 161 {
 162         if (entry != NULL)
 163                 kmem_cache_free(hist->dccprxh_slab, entry);
 164 }
 165
 166 extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
 167                                struct list_head *list);
 168
 169 static inline struct dccp_rx_hist_entry *
 170                 dccp_rx_hist_head(struct list_head *list)
 171 {
 172         struct dccp_rx_hist_entry *head = NULL;
 173
 174         if (!list_empty(list))
 175                 head = list_entry(list->next, struct dccp_rx_hist_entry,
 176                                   dccphrx_node);
 177         return head;
 178 }
 179
 180 static inline int
 181         dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
 182 {
 183         return entry->dccphrx_type == DCCP_PKT_DATA ||
 184                entry->dccphrx_type == DCCP_PKT_DATAACK;
 185 }
 186
 187 extern void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
 188                                    struct list_head *rx_list,
 189                                    struct list_head *li_list,
 190                                    struct dccp_rx_hist_entry *packet,
 191                                    u64 nonloss_seqno);
 192
 193 extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
 194                                     struct list_head *li_list, u8 *win_loss);
 195
 196 #endif /* _DCCP_PKT_HIST_ */