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/ktime.h>
  41 #include <linux/list.h>
  42 #include <linux/slab.h>
  43 #include <linux/time.h>
  44
  45 #include "../../dccp.h"
  46
  47 /* Number of later packets received before one is considered lost */
  48 #define TFRC_RECV_NUM_LATE_LOSS  3
  49
  50 #define TFRC_WIN_COUNT_PER_RTT   4
  51 #define TFRC_WIN_COUNT_LIMIT    16
  52
  53 /*
  54  *      Transmitter History data structures and declarations
  55  */
  56 struct dccp_tx_hist_entry {
  57         struct list_head dccphtx_node;
  58         u64              dccphtx_seqno:48,
  59                          dccphtx_sent:1;
  60         u32              dccphtx_rtt;
  61         struct timeval   dccphtx_tstamp;
  62 };
  63
  64 struct dccp_tx_hist {
  65         struct kmem_cache *dccptxh_slab;
  66 };
  67
  68 extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
  69 extern void                 dccp_tx_hist_delete(struct dccp_tx_hist *hist);
  70
  71 static inline struct dccp_tx_hist_entry *
  72                         dccp_tx_hist_entry_new(struct dccp_tx_hist *hist,
  73                                                const gfp_t prio)
  74 {
  75         struct dccp_tx_hist_entry *entry = kmem_cache_alloc(hist->dccptxh_slab,
  76                                                             prio);
  77
  78         if (entry != NULL)
  79                 entry->dccphtx_sent = 0;
  80
  81         return entry;
  82 }
  83
  84 static inline struct dccp_tx_hist_entry *
  85                         dccp_tx_hist_head(struct list_head *list)
  86 {
  87         struct dccp_tx_hist_entry *head = NULL;
  88
  89         if (!list_empty(list))
  90                 head = list_entry(list->next, struct dccp_tx_hist_entry,
  91                                   dccphtx_node);
  92         return head;
  93 }
  94
  95 extern struct dccp_tx_hist_entry *
  96                         dccp_tx_hist_find_entry(const struct list_head *list,
  97                                                 const u64 seq);
  98
  99 static inline void dccp_tx_hist_add_entry(struct list_head *list,
 100                                           struct dccp_tx_hist_entry *entry)
 101 {
 102         list_add(&entry->dccphtx_node, list);
 103 }
 104
 105 static inline void dccp_tx_hist_entry_delete(struct dccp_tx_hist *hist,
 106                                              struct dccp_tx_hist_entry *entry)
 107 {
 108         if (entry != NULL)
 109                 kmem_cache_free(hist->dccptxh_slab, entry);
 110 }
 111
 112 extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
 113                                struct list_head *list);
 114
 115 extern void dccp_tx_hist_purge_older(struct dccp_tx_hist *hist,
 116                                      struct list_head *list,
 117                                      struct dccp_tx_hist_entry *next);
 118
 119 /*
 120  *      Receiver History data structures and declarations
 121  */
 122 struct dccp_rx_hist_entry {
 123         struct list_head dccphrx_node;
 124         u64              dccphrx_seqno:48,
 125                          dccphrx_ccval:4,
 126                          dccphrx_type:4;
 127         u32              dccphrx_ndp; /* In fact it is from 8 to 24 bits */
 128         ktime_t          dccphrx_tstamp;
 129 };
 130
 131 struct dccp_rx_hist {
 132         struct kmem_cache *dccprxh_slab;
 133 };
 134
 135 extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
 136 extern void             dccp_rx_hist_delete(struct dccp_rx_hist *hist);
 137
 138 static inline struct dccp_rx_hist_entry *
 139                         dccp_rx_hist_entry_new(struct dccp_rx_hist *hist,
 140                                                const u32 ndp,
 141                                                const struct sk_buff *skb,
 142                                                const gfp_t prio)
 143 {
 144         struct dccp_rx_hist_entry *entry = kmem_cache_alloc(hist->dccprxh_slab,
 145                                                             prio);
 146
 147         if (entry != NULL) {
 148                 const struct dccp_hdr *dh = dccp_hdr(skb);
 149
 150                 entry->dccphrx_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
 151                 entry->dccphrx_ccval = dh->dccph_ccval;
 152                 entry->dccphrx_type  = dh->dccph_type;
 153                 entry->dccphrx_ndp   = ndp;
 154                 entry->dccphrx_tstamp = ktime_get_real();
 155         }
 156
 157         return entry;
 158 }
 159
 160 static inline struct dccp_rx_hist_entry *
 161                         dccp_rx_hist_head(struct list_head *list)
 162 {
 163         struct dccp_rx_hist_entry *head = NULL;
 164
 165         if (!list_empty(list))
 166                 head = list_entry(list->next, struct dccp_rx_hist_entry,
 167                                   dccphrx_node);
 168         return head;
 169 }
 170
 171 extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
 172                                    u8 *ccval);
 173 extern struct dccp_rx_hist_entry *
 174                 dccp_rx_hist_find_data_packet(const struct list_head *list);
 175
 176 extern void dccp_rx_hist_add_packet(struct dccp_rx_hist *hist,
 177                                     struct list_head *rx_list,
 178                                     struct list_head *li_list,
 179                                     struct dccp_rx_hist_entry *packet,
 180                                     u64 nonloss_seqno);
 181
 182 static inline void dccp_rx_hist_entry_delete(struct dccp_rx_hist *hist,
 183                                              struct dccp_rx_hist_entry *entry)
 184 {
 185         if (entry != NULL)
 186                 kmem_cache_free(hist->dccprxh_slab, entry);
 187 }
 188
 189 extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
 190                                struct list_head *list);
 191
 192 static inline int
 193         dccp_rx_hist_entry_data_packet(const struct dccp_rx_hist_entry *entry)
 194 {
 195         return entry->dccphrx_type == DCCP_PKT_DATA ||
 196                entry->dccphrx_type == DCCP_PKT_DATAACK;
 197 }
 198
 199 extern u64 dccp_rx_hist_detect_loss(struct list_head *rx_list,
 200                                     struct list_head *li_list, u8 *win_loss);
 201
 202 #endif /* _DCCP_PKT_HIST_ */