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 "msg.h" 41 #include "node.h" 42 43 /* Out-of-range value for link sequence numbers 44 */ 45 #define INVALID_LINK_SEQ 0x10000 46 47 /* Link working states 48 */ 49 #define WORKING_WORKING 560810u 50 #define WORKING_UNKNOWN 560811u 51 #define RESET_UNKNOWN 560812u 52 #define RESET_RESET 560813u 53 54 /* Link endpoint execution states 55 */ 56 #define LINK_STARTED 0x0001 57 #define LINK_STOPPED 0x0002 58 59 /* Starting value for maximum packet size negotiation on unicast links 60 * (unless bearer MTU is less) 61 */ 62 #define MAX_PKT_DEFAULT 1500 63 64 struct tipc_stats { 65 u32 sent_info; /* used in counting # sent packets */ 66 u32 recv_info; /* used in counting # recv'd packets */ 67 u32 sent_states; 68 u32 recv_states; 69 u32 sent_probes; 70 u32 recv_probes; 71 u32 sent_nacks; 72 u32 recv_nacks; 73 u32 sent_acks; 74 u32 sent_bundled; 75 u32 sent_bundles; 76 u32 recv_bundled; 77 u32 recv_bundles; 78 u32 retransmitted; 79 u32 sent_fragmented; 80 u32 sent_fragments; 81 u32 recv_fragmented; 82 u32 recv_fragments; 83 u32 link_congs; /* # port sends blocked by congestion */ 84 u32 deferred_recv; 85 u32 duplicates; 86 u32 max_queue_sz; /* send queue size high water mark */ 87 u32 accu_queue_sz; /* used for send queue size profiling */ 88 u32 queue_sz_counts; /* used for send queue size profiling */ 89 u32 msg_length_counts; /* used for message length profiling */ 90 u32 msg_lengths_total; /* used for message length profiling */ 91 u32 msg_length_profile[7]; /* used for msg. length profiling */ 92 }; 93 94 /** 95 * struct tipc_link - TIPC link data structure 96 * @addr: network address of link's peer node 97 * @name: link name character string 98 * @media_addr: media address to use when sending messages over link 99 * @timer: link timer 100 * @owner: pointer to peer node 101 * @flags: execution state flags for link endpoint instance 102 * @checkpoint: reference point for triggering link continuity checking 103 * @peer_session: link session # being used by peer end of link 104 * @peer_bearer_id: bearer id used by link's peer endpoint 105 * @bearer_id: local bearer id used by link 106 * @tolerance: minimum link continuity loss needed to reset link [in ms] 107 * @continuity_interval: link continuity testing interval [in ms] 108 * @abort_limit: # of unacknowledged continuity probes needed to reset link 109 * @state: current state of link FSM 110 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state 111 * @proto_msg: template for control messages generated by link 112 * @pmsg: convenience pointer to "proto_msg" field 113 * @priority: current link priority 114 * @net_plane: current link network plane ('A' through 'H') 115 * @queue_limit: outbound message queue congestion thresholds (indexed by user) 116 * @exp_msg_count: # of tunnelled messages expected during link changeover 117 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 118 * @max_pkt: current maximum packet size for this link 119 * @max_pkt_target: desired maximum packet size for this link 120 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target) 121 * @out_queue_size: # of messages in outbound message queue 122 * @first_out: ptr to first outbound message in queue 123 * @last_out: ptr to last outbound message in queue 124 * @next_out_no: next sequence number to use for outbound messages 125 * @last_retransmitted: sequence number of most recently retransmitted message 126 * @stale_count: # of identical retransmit requests made by peer 127 * @next_in_no: next sequence number to expect for inbound messages 128 * @deferred_inqueue_sz: # of messages in inbound message queue 129 * @oldest_deferred_in: ptr to first inbound message in queue 130 * @newest_deferred_in: ptr to last inbound message in queue 131 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 132 * @proto_msg_queue: ptr to (single) outbound control message 133 * @retransm_queue_size: number of messages to retransmit 134 * @retransm_queue_head: sequence number of first message to retransmit 135 * @next_out: ptr to first unsent outbound message in queue 136 * @waiting_sks: linked list of sockets waiting for link congestion to abate 137 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 138 * @reasm_buf: head of partially reassembled inbound message fragments 139 * @stats: collects statistics regarding link activity 140 */ 141 struct tipc_link { 142 u32 addr; 143 char name[TIPC_MAX_LINK_NAME]; 144 struct tipc_media_addr media_addr; 145 struct timer_list timer; 146 struct tipc_node *owner; 147 148 /* Management and link supervision data */ 149 unsigned int flags; 150 u32 checkpoint; 151 u32 peer_session; 152 u32 peer_bearer_id; 153 u32 bearer_id; 154 u32 tolerance; 155 u32 continuity_interval; 156 u32 abort_limit; 157 int state; 158 u32 fsm_msg_cnt; 159 struct { 160 unchar hdr[INT_H_SIZE]; 161 unchar body[TIPC_MAX_IF_NAME]; 162 } proto_msg; 163 struct tipc_msg *pmsg; 164 u32 priority; 165 char net_plane; 166 u32 queue_limit[15]; /* queue_limit[0]==window limit */ 167 168 /* Changeover */ 169 u32 exp_msg_count; 170 u32 reset_checkpoint; 171 172 /* Max packet negotiation */ 173 u32 max_pkt; 174 u32 max_pkt_target; 175 u32 max_pkt_probes; 176 177 /* Sending */ 178 u32 out_queue_size; 179 struct sk_buff *first_out; 180 struct sk_buff *last_out; 181 u32 next_out_no; 182 u32 last_retransmitted; 183 u32 stale_count; 184 185 /* Reception */ 186 u32 next_in_no; 187 u32 deferred_inqueue_sz; 188 struct sk_buff *oldest_deferred_in; 189 struct sk_buff *newest_deferred_in; 190 u32 unacked_window; 191 192 /* Congestion handling */ 193 struct sk_buff *proto_msg_queue; 194 u32 retransm_queue_size; 195 u32 retransm_queue_head; 196 struct sk_buff *next_out; 197 struct sk_buff_head waiting_sks; 198 199 /* Fragmentation/reassembly */ 200 u32 long_msg_seq_no; 201 struct sk_buff *reasm_buf; 202 203 /* Statistics */ 204 struct tipc_stats stats; 205 }; 206 207 struct tipc_port; 208 209 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, 210 struct tipc_bearer *b_ptr, 211 const struct tipc_media_addr *media_addr); 212 void tipc_link_delete_list(unsigned int bearer_id, bool shutting_down); 213 void tipc_link_failover_send_queue(struct tipc_link *l_ptr); 214 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr, struct tipc_link *dest); 215 void tipc_link_reset_fragments(struct tipc_link *l_ptr); 216 int tipc_link_is_up(struct tipc_link *l_ptr); 217 int tipc_link_is_active(struct tipc_link *l_ptr); 218 void tipc_link_purge_queues(struct tipc_link *l_ptr); 219 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, 220 int req_tlv_space, 221 u16 cmd); 222 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, 223 int req_tlv_space); 224 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, 225 int req_tlv_space); 226 void tipc_link_reset_all(struct tipc_node *node); 227 void tipc_link_reset(struct tipc_link *l_ptr); 228 void tipc_link_reset_list(unsigned int bearer_id); 229 int tipc_link_xmit(struct sk_buff *buf, u32 dest, u32 selector); 230 int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf); 231 u32 tipc_link_get_max_pkt(u32 dest, u32 selector); 232 void tipc_link_bundle_rcv(struct sk_buff *buf); 233 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob, 234 u32 gap, u32 tolerance, u32 priority, u32 acked_mtu); 235 void tipc_link_push_queue(struct tipc_link *l_ptr); 236 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail, 237 struct sk_buff *buf); 238 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 239 void tipc_link_retransmit(struct tipc_link *l_ptr, 240 struct sk_buff *start, u32 retransmits); 241 242 /* 243 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 244 */ 245 static inline u32 buf_seqno(struct sk_buff *buf) 246 { 247 return msg_seqno(buf_msg(buf)); 248 } 249 250 static inline u32 mod(u32 x) 251 { 252 return x & 0xffffu; 253 } 254 255 static inline int between(u32 lower, u32 upper, u32 n) 256 { 257 if ((lower < n) && (n < upper)) 258 return 1; 259 if ((upper < lower) && ((n > lower) || (n < upper))) 260 return 1; 261 return 0; 262 } 263 264 static inline int less_eq(u32 left, u32 right) 265 { 266 return mod(right - left) < 32768u; 267 } 268 269 static inline int less(u32 left, u32 right) 270 { 271 return less_eq(left, right) && (mod(right) != mod(left)); 272 } 273 274 static inline u32 lesser(u32 left, u32 right) 275 { 276 return less_eq(left, right) ? left : right; 277 } 278 279 280 /* 281 * Link status checking routines 282 */ 283 static inline int link_working_working(struct tipc_link *l_ptr) 284 { 285 return l_ptr->state == WORKING_WORKING; 286 } 287 288 static inline int link_working_unknown(struct tipc_link *l_ptr) 289 { 290 return l_ptr->state == WORKING_UNKNOWN; 291 } 292 293 static inline int link_reset_unknown(struct tipc_link *l_ptr) 294 { 295 return l_ptr->state == RESET_UNKNOWN; 296 } 297 298 static inline int link_reset_reset(struct tipc_link *l_ptr) 299 { 300 return l_ptr->state == RESET_RESET; 301 } 302 303 static inline int link_congested(struct tipc_link *l_ptr) 304 { 305 return l_ptr->out_queue_size >= l_ptr->queue_limit[0]; 306 } 307 308 #endif 309