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
  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  */
  55 struct 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
  63 struct dccp_tx_hist {
  64         struct kmem_cache *dccptxh_slab;
  65 };
  66
  67 extern struct dccp_tx_hist *dccp_tx_hist_new(const char *name);
  68 extern void                 dccp_tx_hist_delete(struct dccp_tx_hist *hist);
  69
  70 static 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
  83 static 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
  94 extern struct dccp_tx_hist_entry *
  95                         dccp_tx_hist_find_entry(const struct list_head *list,
  96                                                 const u64 seq);
  97
  98 static 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
 104 static 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
 111 extern void dccp_tx_hist_purge(struct dccp_tx_hist *hist,
 112                                struct list_head *list);
 113
 114 extern 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  */
 121 struct 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
 130 struct dccp_rx_hist {
 131         struct kmem_cache *dccprxh_slab;
 132 };
 133
 134 extern struct dccp_rx_hist *dccp_rx_hist_new(const char *name);
 135 extern void             dccp_rx_hist_delete(struct dccp_rx_hist *hist);
 136
 137 static 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
 159 static 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
 170 extern int dccp_rx_hist_find_entry(const struct list_head *list, const u64 seq,
 171                                    u8 *ccval);
 172 extern struct dccp_rx_hist_entry *
 173                 dccp_rx_hist_find_data_packet(const struct list_head *list);
 174
 175 extern 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
 181 static 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
 188 extern void dccp_rx_hist_purge(struct dccp_rx_hist *hist,
 189                                struct list_head *list);
 190
 191 static 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
 198 extern 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_ */