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 71struct 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 * @checkpoint: reference point for triggering link continuity checking 111 * @peer_session: link session # being used by peer end of link 112 * @peer_bearer_id: bearer id used by link's peer endpoint 113 * @bearer_id: local bearer id used by link 114 * @tolerance: minimum link continuity loss needed to reset link [in ms] 115 * @cont_intv: link continuity testing interval 116 * @abort_limit: # of unacknowledged continuity probes needed to reset link 117 * @state: current state of link FSM 118 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state 119 * @proto_msg: template for control messages generated by link 120 * @pmsg: convenience pointer to "proto_msg" field 121 * @priority: current link priority 122 * @net_plane: current link network plane ('A' through 'H') 123 * @backlog_limit: backlog queue congestion thresholds (indexed by importance) 124 * @exp_msg_count: # of tunnelled messages expected during link changeover 125 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 126 * @mtu: current maximum packet size for this link 127 * @advertised_mtu: advertised own mtu when link is being established 128 * @transmitq: queue for sent, non-acked messages 129 * @backlogq: queue for messages waiting to be sent 130 * @next_out_no: next sequence number to use for outbound messages 131 * @last_retransmitted: sequence number of most recently retransmitted message 132 * @stale_count: # of identical retransmit requests made by peer 133 * @next_in_no: next sequence number to expect for inbound messages 134 * @deferred_queue: deferred queue saved OOS b'cast message received from node 135 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 136 * @inputq: buffer queue for messages to be delivered upwards 137 * @namedq: buffer queue for name table messages to be delivered upwards 138 * @next_out: ptr to first unsent outbound message in queue 139 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate 140 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 141 * @reasm_buf: head of partially reassembled inbound message fragments 142 * @stats: collects statistics regarding link activity 143 */ 144struct tipc_link { 145 u32 addr; 146 char name[TIPC_MAX_LINK_NAME]; 147 struct tipc_media_addr media_addr; 148 struct timer_list timer; 149 struct tipc_node *owner; 150 struct kref ref; 151 152 /* Management and link supervision data */ 153 unsigned int flags; 154 u32 checkpoint; 155 u32 peer_session; 156 u32 peer_bearer_id; 157 u32 bearer_id; 158 u32 tolerance; 159 unsigned long cont_intv; 160 u32 abort_limit; 161 int state; 162 u32 fsm_msg_cnt; 163 struct { 164 unchar hdr[INT_H_SIZE]; 165 unchar body[TIPC_MAX_IF_NAME]; 166 } proto_msg; 167 struct tipc_msg *pmsg; 168 u32 priority; 169 char net_plane; 170 u16 synch_point; 171 172 /* Failover */ 173 u16 failover_pkts; 174 u16 failover_checkpt; 175 struct sk_buff *failover_skb; 176 177 /* Max packet negotiation */ 178 u16 mtu; 179 u16 advertised_mtu; 180 181 /* Sending */ 182 struct sk_buff_head transmq; 183 struct sk_buff_head backlogq; 184 struct { 185 u16 len; 186 u16 limit; 187 } backlog[5]; 188 u32 next_out_no; 189 u32 window; 190 u32 last_retransmitted; 191 u32 stale_count; 192 193 /* Reception */ 194 u32 next_in_no; 195 u32 rcv_unacked; 196 struct sk_buff_head deferdq; 197 struct sk_buff_head inputq; 198 struct sk_buff_head namedq; 199 200 /* Congestion handling */ 201 struct sk_buff_head wakeupq; 202 203 /* Fragmentation/reassembly */ 204 struct sk_buff *reasm_buf; 205 206 /* Statistics */ 207 struct tipc_stats stats; 208}; 209 210struct tipc_port; 211 212struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, 213 struct tipc_bearer *b_ptr, 214 const struct tipc_media_addr *media_addr); 215void tipc_link_delete(struct tipc_link *link); 216void tipc_link_delete_list(struct net *net, unsigned int bearer_id, 217 bool shutting_down); 218void tipc_link_failover_send_queue(struct tipc_link *l_ptr); 219void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr, struct tipc_link *dest); 220void tipc_link_reset_fragments(struct tipc_link *l_ptr); 221int tipc_link_is_up(struct tipc_link *l_ptr); 222int tipc_link_is_active(struct tipc_link *l_ptr); 223void tipc_link_purge_queues(struct tipc_link *l_ptr); 224void tipc_link_reset_all(struct tipc_node *node); 225void tipc_link_reset(struct tipc_link *l_ptr); 226void tipc_link_reset_list(struct net *net, unsigned int bearer_id); 227int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest, 228 u32 selector); 229int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dest, 230 u32 selector); 231int __tipc_link_xmit(struct net *net, struct tipc_link *link, 232 struct sk_buff_head *list); 233void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob, 234 u32 gap, u32 tolerance, u32 priority); 235void tipc_link_push_packets(struct tipc_link *l_ptr); 236u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *buf); 237void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 238void tipc_link_retransmit(struct tipc_link *l_ptr, 239 struct sk_buff *start, u32 retransmits); 240struct sk_buff *tipc_skb_queue_next(const struct sk_buff_head *list, 241 const struct sk_buff *skb); 242 243int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb); 244int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info); 245int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info); 246int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info); 247int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]); 248void link_prepare_wakeup(struct tipc_link *l); 249 250/* 251 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 252 */ 253static inline u32 buf_seqno(struct sk_buff *buf) 254{ 255 return msg_seqno(buf_msg(buf)); 256} 257 258static inline u32 mod(u32 x) 259{ 260 return x & 0xffffu; 261} 262 263static inline int less_eq(u32 left, u32 right) 264{ 265 return mod(right - left) < 32768u; 266} 267 268static inline int more(u32 left, u32 right) 269{ 270 return !less_eq(left, right); 271} 272 273static inline int less(u32 left, u32 right) 274{ 275 return less_eq(left, right) && (mod(right) != mod(left)); 276} 277 278static inline u32 lesser(u32 left, u32 right) 279{ 280 return less_eq(left, right) ? left : right; 281} 282 283static inline u32 link_own_addr(struct tipc_link *l) 284{ 285 return msg_prevnode(l->pmsg); 286} 287 288/* 289 * Link status checking routines 290 */ 291static inline int link_working_working(struct tipc_link *l_ptr) 292{ 293 return l_ptr->state == WORKING_WORKING; 294} 295 296static inline int link_working_unknown(struct tipc_link *l_ptr) 297{ 298 return l_ptr->state == WORKING_UNKNOWN; 299} 300 301static inline int link_reset_unknown(struct tipc_link *l_ptr) 302{ 303 return l_ptr->state == RESET_UNKNOWN; 304} 305 306static inline int link_reset_reset(struct tipc_link *l_ptr) 307{ 308 return l_ptr->state == RESET_RESET; 309} 310 311#endif 312