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 working states
  53  */
  54 #define WORKING_WORKING 560810u
  55 #define WORKING_UNKNOWN 560811u
  56 #define RESET_UNKNOWN   560812u
  57 #define RESET_RESET     560813u
  58
  59 /* Link endpoint execution states
  60  */
  61 #define LINK_STARTED     0x0001
  62 #define LINK_STOPPED     0x0002
  63 #define LINK_SYNCHING    0x0004
  64 #define LINK_FAILINGOVER 0x0008
  65
  66 /* Starting value for maximum packet size negotiation on unicast links
  67  * (unless bearer MTU is less)
  68  */
  69 #define MAX_PKT_DEFAULT 1500
  70
  71 struct tipc_stats {
  72         u32 sent_info;          /* used in counting # sent packets */
  73         u32 recv_info;          /* used in counting # recv'd packets */
  74         u32 sent_states;
  75         u32 recv_states;
  76         u32 sent_probes;
  77         u32 recv_probes;
  78         u32 sent_nacks;
  79         u32 recv_nacks;
  80         u32 sent_acks;
  81         u32 sent_bundled;
  82         u32 sent_bundles;
  83         u32 recv_bundled;
  84         u32 recv_bundles;
  85         u32 retransmitted;
  86         u32 sent_fragmented;
  87         u32 sent_fragments;
  88         u32 recv_fragmented;
  89         u32 recv_fragments;
  90         u32 link_congs;         /* # port sends blocked by congestion */
  91         u32 deferred_recv;
  92         u32 duplicates;
  93         u32 max_queue_sz;       /* send queue size high water mark */
  94         u32 accu_queue_sz;      /* used for send queue size profiling */
  95         u32 queue_sz_counts;    /* used for send queue size profiling */
  96         u32 msg_length_counts;  /* used for message length profiling */
  97         u32 msg_lengths_total;  /* used for message length profiling */
  98         u32 msg_length_profile[7]; /* used for msg. length profiling */
  99 };
 100
 101 /**
 102  * struct tipc_link - TIPC link data structure
 103  * @addr: network address of link's peer node
 104  * @name: link name character string
 105  * @media_addr: media address to use when sending messages over link
 106  * @timer: link timer
 107  * @owner: pointer to peer node
 108  * @refcnt: reference counter for permanent references (owner node & timer)
 109  * @flags: execution state flags for link endpoint instance
 110  * @peer_session: link session # being used by peer end of link
 111  * @peer_bearer_id: bearer id used by link's peer endpoint
 112  * @bearer_id: local bearer id used by link
 113  * @tolerance: minimum link continuity loss needed to reset link [in ms]
 114  * @keepalive_intv: link keepalive timer interval
 115  * @abort_limit: # of unacknowledged continuity probes needed to reset link
 116  * @state: current state of link FSM
 117  * @silent_intv_cnt: # of timer intervals without any reception from peer
 118  * @proto_msg: template for control messages generated by link
 119  * @pmsg: convenience pointer to "proto_msg" field
 120  * @priority: current link priority
 121  * @net_plane: current link network plane ('A' through 'H')
 122  * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
 123  * @exp_msg_count: # of tunnelled messages expected during link changeover
 124  * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
 125  * @mtu: current maximum packet size for this link
 126  * @advertised_mtu: advertised own mtu when link is being established
 127  * @transmitq: queue for sent, non-acked messages
 128  * @backlogq: queue for messages waiting to be sent
 129  * @snt_nxt: next sequence number to use for outbound messages
 130  * @last_retransmitted: sequence number of most recently retransmitted message
 131  * @stale_count: # of identical retransmit requests made by peer
 132  * @rcv_nxt: next sequence number to expect for inbound messages
 133  * @deferred_queue: deferred queue saved OOS b'cast message received from node
 134  * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
 135  * @inputq: buffer queue for messages to be delivered upwards
 136  * @namedq: buffer queue for name table messages to be delivered upwards
 137  * @next_out: ptr to first unsent outbound message in queue
 138  * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
 139  * @long_msg_seq_no: next identifier to use for outbound fragmented messages
 140  * @reasm_buf: head of partially reassembled inbound message fragments
 141  * @stats: collects statistics regarding link activity
 142  */
 143 struct tipc_link {
 144         u32 addr;
 145         char name[TIPC_MAX_LINK_NAME];
 146         struct tipc_media_addr media_addr;
 147         struct timer_list timer;
 148         struct tipc_node *owner;
 149         struct kref ref;
 150
 151         /* Management and link supervision data */
 152         unsigned int flags;
 153         u32 peer_session;
 154         u32 peer_bearer_id;
 155         u32 bearer_id;
 156         u32 tolerance;
 157         unsigned long keepalive_intv;
 158         u32 abort_limit;
 159         int state;
 160         u32 silent_intv_cnt;
 161         struct {
 162                 unchar hdr[INT_H_SIZE];
 163                 unchar body[TIPC_MAX_IF_NAME];
 164         } proto_msg;
 165         struct tipc_msg *pmsg;
 166         u32 priority;
 167         char net_plane;
 168         u16 synch_point;
 169
 170         /* Failover */
 171         u16 failover_pkts;
 172         u16 failover_checkpt;
 173         struct sk_buff *failover_skb;
 174
 175         /* Max packet negotiation */
 176         u16 mtu;
 177         u16 advertised_mtu;
 178
 179         /* Sending */
 180         struct sk_buff_head transmq;
 181         struct sk_buff_head backlogq;
 182         struct {
 183                 u16 len;
 184                 u16 limit;
 185         } backlog[5];
 186         u16 snd_nxt;
 187         u16 last_retransm;
 188         u32 window;
 189         u32 stale_count;
 190
 191         /* Reception */
 192         u16 rcv_nxt;
 193         u32 rcv_unacked;
 194         struct sk_buff_head deferdq;
 195         struct sk_buff_head inputq;
 196         struct sk_buff_head namedq;
 197
 198         /* Congestion handling */
 199         struct sk_buff_head wakeupq;
 200
 201         /* Fragmentation/reassembly */
 202         struct sk_buff *reasm_buf;
 203
 204         /* Statistics */
 205         struct tipc_stats stats;
 206 };
 207
 208 struct tipc_port;
 209
 210 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
 211                               struct tipc_bearer *b_ptr,
 212                               const struct tipc_media_addr *media_addr);
 213 void tipc_link_delete(struct tipc_link *link);
 214 void tipc_link_delete_list(struct net *net, unsigned int bearer_id);
 215 void tipc_link_failover_send_queue(struct tipc_link *l_ptr);
 216 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr, struct tipc_link *dest);
 217 void tipc_link_reset_fragments(struct tipc_link *l_ptr);
 218 int tipc_link_is_up(struct tipc_link *l_ptr);
 219 int tipc_link_is_active(struct tipc_link *l_ptr);
 220 void tipc_link_purge_queues(struct tipc_link *l_ptr);
 221 void tipc_link_purge_backlog(struct tipc_link *l);
 222 void tipc_link_reset_all(struct tipc_node *node);
 223 void tipc_link_reset(struct tipc_link *l_ptr);
 224 int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
 225                        u32 selector);
 226 int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dest,
 227                    u32 selector);
 228 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
 229                      struct sk_buff_head *list);
 230 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob,
 231                           u32 gap, u32 tolerance, u32 priority);
 232 void tipc_link_push_packets(struct tipc_link *l_ptr);
 233 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *buf);
 234 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window);
 235 void tipc_link_retransmit(struct tipc_link *l_ptr,
 236                           struct sk_buff *start, u32 retransmits);
 237 struct sk_buff *tipc_skb_queue_next(const struct sk_buff_head *list,
 238                                     const struct sk_buff *skb);
 239
 240 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
 241 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info);
 242 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info);
 243 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info);
 244 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]);
 245 void link_prepare_wakeup(struct tipc_link *l);
 246
 247 static inline u32 link_own_addr(struct tipc_link *l)
 248 {
 249         return msg_prevnode(l->pmsg);
 250 }
 251
 252 /*
 253  * Link status checking routines
 254  */
 255 static inline int link_working_working(struct tipc_link *l_ptr)
 256 {
 257         return l_ptr->state == WORKING_WORKING;
 258 }
 259
 260 static inline int link_working_unknown(struct tipc_link *l_ptr)
 261 {
 262         return l_ptr->state == WORKING_UNKNOWN;
 263 }
 264
 265 static inline int link_reset_unknown(struct tipc_link *l_ptr)
 266 {
 267         return l_ptr->state == RESET_UNKNOWN;
 268 }
 269
 270 static inline int link_reset_reset(struct tipc_link *l_ptr)
 271 {
 272         return l_ptr->state == RESET_RESET;
 273 }
 274
 275 #endif