net/tipc/link.h

   1 /*
   2  * net/tipc/link.h: Include file for TIPC link code
   3  *
   4  * Copyright (c) 1995-2006, 2013-2014, Ericsson AB
   5  * Copyright (c) 2004-2005, 2010-2011, Wind River Systems
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. Neither the names of the copyright holders nor the names of its
  17  *    contributors may be used to endorse or promote products derived from
  18  *    this software without specific prior written permission.
  19  *
  20  * Alternatively, this software may be distributed under the terms of the
  21  * GNU General Public License ("GPL") version 2 as published by the Free
  22  * Software Foundation.
  23  *
  24  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  25  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  27  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
  28  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  29  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  30  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  31  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  32  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  34  * POSSIBILITY OF SUCH DAMAGE.
  35  */
  36
  37 #ifndef _TIPC_LINK_H
  38 #define _TIPC_LINK_H
  39
  40 #include <net/genetlink.h>
  41 #include "msg.h"
  42 #include "node.h"
  43
  44 /* TIPC-specific error codes
  45 */
  46 #define ELINKCONG EAGAIN        /* link congestion <=> resource unavailable */
  47
  48 /* Out-of-range value for link sequence numbers
  49  */
  50 #define INVALID_LINK_SEQ 0x10000
  51
  52 /* Link FSM events:
  53  */
  54 enum {
  55         LINK_ESTABLISH_EVT       = 0xec1ab1e,
  56         LINK_PEER_RESET_EVT      = 0x9eed0e,
  57         LINK_FAILURE_EVT         = 0xfa110e,
  58         LINK_RESET_EVT           = 0x10ca1d0e,
  59         LINK_FAILOVER_BEGIN_EVT  = 0xfa110bee,
  60         LINK_FAILOVER_END_EVT    = 0xfa110ede,
  61         LINK_SYNCH_BEGIN_EVT     = 0xc1ccbee,
  62         LINK_SYNCH_END_EVT       = 0xc1ccede
  63 };
  64
  65 /* Events returned from link at packet reception or at timeout
  66  */
  67 enum {
  68         TIPC_LINK_UP_EVT       = 1,
  69         TIPC_LINK_DOWN_EVT     = (1 << 1),
  70         TIPC_LINK_SND_BC_ACK   = (1 << 2)
  71 };
  72
  73 /* Starting value for maximum packet size negotiation on unicast links
  74  * (unless bearer MTU is less)
  75  */
  76 #define MAX_PKT_DEFAULT 1500
  77
  78 struct tipc_stats {
  79         u32 sent_info;          /* used in counting # sent packets */
  80         u32 recv_info;          /* used in counting # recv'd packets */
  81         u32 sent_states;
  82         u32 recv_states;
  83         u32 sent_probes;
  84         u32 recv_probes;
  85         u32 sent_nacks;
  86         u32 recv_nacks;
  87         u32 sent_acks;
  88         u32 sent_bundled;
  89         u32 sent_bundles;
  90         u32 recv_bundled;
  91         u32 recv_bundles;
  92         u32 retransmitted;
  93         u32 sent_fragmented;
  94         u32 sent_fragments;
  95         u32 recv_fragmented;
  96         u32 recv_fragments;
  97         u32 link_congs;         /* # port sends blocked by congestion */
  98         u32 deferred_recv;
  99         u32 duplicates;
 100         u32 max_queue_sz;       /* send queue size high water mark */
 101         u32 accu_queue_sz;      /* used for send queue size profiling */
 102         u32 queue_sz_counts;    /* used for send queue size profiling */
 103         u32 msg_length_counts;  /* used for message length profiling */
 104         u32 msg_lengths_total;  /* used for message length profiling */
 105         u32 msg_length_profile[7]; /* used for msg. length profiling */
 106 };
 107
 108 /**
 109  * struct tipc_link - TIPC link data structure
 110  * @addr: network address of link's peer node
 111  * @name: link name character string
 112  * @media_addr: media address to use when sending messages over link
 113  * @timer: link timer
 114  * @net: pointer to namespace struct
 115  * @refcnt: reference counter for permanent references (owner node & timer)
 116  * @peer_session: link session # being used by peer end of link
 117  * @peer_bearer_id: bearer id used by link's peer endpoint
 118  * @bearer_id: local bearer id used by link
 119  * @tolerance: minimum link continuity loss needed to reset link [in ms]
 120  * @keepalive_intv: link keepalive timer interval
 121  * @abort_limit: # of unacknowledged continuity probes needed to reset link
 122  * @state: current state of link FSM
 123  * @peer_caps: bitmap describing capabilities of peer node
 124  * @silent_intv_cnt: # of timer intervals without any reception from peer
 125  * @proto_msg: template for control messages generated by link
 126  * @pmsg: convenience pointer to "proto_msg" field
 127  * @priority: current link priority
 128  * @net_plane: current link network plane ('A' through 'H')
 129  * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
 130  * @exp_msg_count: # of tunnelled messages expected during link changeover
 131  * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
 132  * @mtu: current maximum packet size for this link
 133  * @advertised_mtu: advertised own mtu when link is being established
 134  * @transmitq: queue for sent, non-acked messages
 135  * @backlogq: queue for messages waiting to be sent
 136  * @snt_nxt: next sequence number to use for outbound messages
 137  * @last_retransmitted: sequence number of most recently retransmitted message
 138  * @stale_count: # of identical retransmit requests made by peer
 139  * @ackers: # of peers that needs to ack each packet before it can be released
 140  * @acked: # last packet acked by a certain peer. Used for broadcast.
 141  * @rcv_nxt: next sequence number to expect for inbound messages
 142  * @deferred_queue: deferred queue saved OOS b'cast message received from node
 143  * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
 144  * @inputq: buffer queue for messages to be delivered upwards
 145  * @namedq: buffer queue for name table messages to be delivered upwards
 146  * @next_out: ptr to first unsent outbound message in queue
 147  * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
 148  * @long_msg_seq_no: next identifier to use for outbound fragmented messages
 149  * @reasm_buf: head of partially reassembled inbound message fragments
 150  * @bc_rcvr: marks that this is a broadcast receiver link
 151  * @stats: collects statistics regarding link activity
 152  */
 153 struct tipc_link {
 154         u32 addr;
 155         char name[TIPC_MAX_LINK_NAME];
 156         struct tipc_media_addr *media_addr;
 157         struct net *net;
 158
 159         /* Management and link supervision data */
 160         u32 peer_session;
 161         u32 peer_bearer_id;
 162         u32 bearer_id;
 163         u32 tolerance;
 164         unsigned long keepalive_intv;
 165         u32 abort_limit;
 166         u32 state;
 167         u16 peer_caps;
 168         bool active;
 169         u32 silent_intv_cnt;
 170         struct {
 171                 unchar hdr[INT_H_SIZE];
 172                 unchar body[TIPC_MAX_IF_NAME];
 173         } proto_msg;
 174         struct tipc_msg *pmsg;
 175         u32 priority;
 176         char net_plane;
 177
 178         /* Failover/synch */
 179         u16 drop_point;
 180         struct sk_buff *failover_reasm_skb;
 181
 182         /* Max packet negotiation */
 183         u16 mtu;
 184         u16 advertised_mtu;
 185
 186         /* Sending */
 187         struct sk_buff_head transmq;
 188         struct sk_buff_head backlogq;
 189         struct {
 190                 u16 len;
 191                 u16 limit;
 192         } backlog[5];
 193         u16 snd_nxt;
 194         u16 last_retransm;
 195         u16 window;
 196         u32 stale_count;
 197
 198         /* Reception */
 199         u16 rcv_nxt;
 200         u32 rcv_unacked;
 201         struct sk_buff_head deferdq;
 202         struct sk_buff_head *inputq;
 203         struct sk_buff_head *namedq;
 204
 205         /* Congestion handling */
 206         struct sk_buff_head wakeupq;
 207
 208         /* Fragmentation/reassembly */
 209         struct sk_buff *reasm_buf;
 210
 211         /* Broadcast */
 212         u16 ackers;
 213         u16 acked;
 214         struct tipc_link *bc_rcvlink;
 215         struct tipc_link *bc_sndlink;
 216         int nack_state;
 217         bool bc_peer_is_up;
 218
 219         /* Statistics */
 220         struct tipc_stats stats;
 221 };
 222
 223 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
 224                       int tolerance, char net_plane, u32 mtu, int priority,
 225                       int window, u32 session, u32 ownnode, u32 peer,
 226                       u16 peer_caps,
 227                       struct tipc_link *bc_sndlink,
 228                       struct tipc_link *bc_rcvlink,
 229                       struct sk_buff_head *inputq,
 230                       struct sk_buff_head *namedq,
 231                       struct tipc_link **link);
 232 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
 233                          int mtu, int window, u16 peer_caps,
 234                          struct sk_buff_head *inputq,
 235                          struct sk_buff_head *namedq,
 236                          struct tipc_link *bc_sndlink,
 237                          struct tipc_link **link);
 238 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
 239                            int mtyp, struct sk_buff_head *xmitq);
 240 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
 241 int tipc_link_fsm_evt(struct tipc_link *l, int evt);
 242 void tipc_link_reset_fragments(struct tipc_link *l_ptr);
 243 bool tipc_link_is_up(struct tipc_link *l);
 244 bool tipc_link_peer_is_down(struct tipc_link *l);
 245 bool tipc_link_is_reset(struct tipc_link *l);
 246 bool tipc_link_is_establishing(struct tipc_link *l);
 247 bool tipc_link_is_synching(struct tipc_link *l);
 248 bool tipc_link_is_failingover(struct tipc_link *l);
 249 bool tipc_link_is_blocked(struct tipc_link *l);
 250 void tipc_link_set_active(struct tipc_link *l, bool active);
 251 void tipc_link_reset(struct tipc_link *l_ptr);
 252 int tipc_link_xmit(struct tipc_link *link,      struct sk_buff_head *list,
 253                    struct sk_buff_head *xmitq);
 254 void tipc_link_set_queue_limits(struct tipc_link *l, u32 window);
 255
 256 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
 257 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info);
 258 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info);
 259 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info);
 260 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]);
 261 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq);
 262 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
 263                   struct sk_buff_head *xmitq);
 264 int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
 265 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
 266                            struct tipc_link *uc_l,
 267                            struct sk_buff_head *xmitq);
 268 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
 269                               struct tipc_link *rcv_l,
 270                               struct sk_buff_head *xmitq);
 271 int tipc_link_bc_peers(struct tipc_link *l);
 272 void tipc_link_set_mtu(struct tipc_link *l, int mtu);
 273 int tipc_link_mtu(struct tipc_link *l);
 274 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
 275                           struct sk_buff_head *xmitq);
 276 void tipc_link_build_bc_sync_msg(struct tipc_link *l,
 277                                  struct sk_buff_head *xmitq);
 278 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr);
 279 void tipc_link_bc_sync_rcv(struct tipc_link *l,   struct tipc_msg *hdr,
 280                            struct sk_buff_head *xmitq);
 281 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
 282                           struct sk_buff_head *xmitq);
 283 #endif