1 /* 2 * net/tipc/link.h: Include file for TIPC link code 3 * 4 * Copyright (c) 1995-2006, 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 /* 44 * Link reassembly status codes 45 */ 46 #define LINK_REASM_ERROR -1 47 #define LINK_REASM_COMPLETE 1 48 49 /* 50 * Out-of-range value for link sequence numbers 51 */ 52 #define INVALID_LINK_SEQ 0x10000 53 54 /* 55 * Link states 56 */ 57 #define WORKING_WORKING 560810u 58 #define WORKING_UNKNOWN 560811u 59 #define RESET_UNKNOWN 560812u 60 #define RESET_RESET 560813u 61 62 /* 63 * Starting value for maximum packet size negotiation on unicast links 64 * (unless bearer MTU is less) 65 */ 66 #define MAX_PKT_DEFAULT 1500 67 68 struct tipc_stats { 69 u32 sent_info; /* used in counting # sent packets */ 70 u32 recv_info; /* used in counting # recv'd packets */ 71 u32 sent_states; 72 u32 recv_states; 73 u32 sent_probes; 74 u32 recv_probes; 75 u32 sent_nacks; 76 u32 recv_nacks; 77 u32 sent_acks; 78 u32 sent_bundled; 79 u32 sent_bundles; 80 u32 recv_bundled; 81 u32 recv_bundles; 82 u32 retransmitted; 83 u32 sent_fragmented; 84 u32 sent_fragments; 85 u32 recv_fragmented; 86 u32 recv_fragments; 87 u32 link_congs; /* # port sends blocked by congestion */ 88 u32 deferred_recv; 89 u32 duplicates; 90 u32 max_queue_sz; /* send queue size high water mark */ 91 u32 accu_queue_sz; /* used for send queue size profiling */ 92 u32 queue_sz_counts; /* used for send queue size profiling */ 93 u32 msg_length_counts; /* used for message length profiling */ 94 u32 msg_lengths_total; /* used for message length profiling */ 95 u32 msg_length_profile[7]; /* used for msg. length profiling */ 96 }; 97 98 /** 99 * struct tipc_link - TIPC link data structure 100 * @addr: network address of link's peer node 101 * @name: link name character string 102 * @media_addr: media address to use when sending messages over link 103 * @timer: link timer 104 * @owner: pointer to peer node 105 * @link_list: adjacent links in bearer's list of links 106 * @started: indicates if link has been started 107 * @checkpoint: reference point for triggering link continuity checking 108 * @peer_session: link session # being used by peer end of link 109 * @peer_bearer_id: bearer id used by link's peer endpoint 110 * @b_ptr: pointer to bearer used by link 111 * @tolerance: minimum link continuity loss needed to reset link [in ms] 112 * @continuity_interval: link continuity testing interval [in ms] 113 * @abort_limit: # of unacknowledged continuity probes needed to reset link 114 * @state: current state of link FSM 115 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state 116 * @proto_msg: template for control messages generated by link 117 * @pmsg: convenience pointer to "proto_msg" field 118 * @priority: current link priority 119 * @queue_limit: outbound message queue congestion thresholds (indexed by user) 120 * @exp_msg_count: # of tunnelled messages expected during link changeover 121 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 122 * @max_pkt: current maximum packet size for this link 123 * @max_pkt_target: desired maximum packet size for this link 124 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target) 125 * @out_queue_size: # of messages in outbound message queue 126 * @first_out: ptr to first outbound message in queue 127 * @last_out: ptr to last outbound message in queue 128 * @next_out_no: next sequence number to use for outbound messages 129 * @last_retransmitted: sequence number of most recently retransmitted message 130 * @stale_count: # of identical retransmit requests made by peer 131 * @next_in_no: next sequence number to expect for inbound messages 132 * @deferred_inqueue_sz: # of messages in inbound message queue 133 * @oldest_deferred_in: ptr to first inbound message in queue 134 * @newest_deferred_in: ptr to last inbound message in queue 135 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 136 * @proto_msg_queue: ptr to (single) outbound control message 137 * @retransm_queue_size: number of messages to retransmit 138 * @retransm_queue_head: sequence number of first message to retransmit 139 * @next_out: ptr to first unsent outbound message in queue 140 * @waiting_ports: linked list of ports waiting for link congestion to abate 141 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 142 * @reasm_head: list head of partially reassembled inbound message fragments 143 * @reasm_tail: last fragment received 144 * @stats: collects statistics regarding link activity 145 */ 146 struct tipc_link { 147 u32 addr; 148 char name[TIPC_MAX_LINK_NAME]; 149 struct tipc_media_addr media_addr; 150 struct timer_list timer; 151 struct tipc_node *owner; 152 struct list_head link_list; 153 154 /* Management and link supervision data */ 155 int started; 156 u32 checkpoint; 157 u32 peer_session; 158 u32 peer_bearer_id; 159 struct tipc_bearer *b_ptr; 160 u32 tolerance; 161 u32 continuity_interval; 162 u32 abort_limit; 163 int state; 164 u32 fsm_msg_cnt; 165 struct { 166 unchar hdr[INT_H_SIZE]; 167 unchar body[TIPC_MAX_IF_NAME]; 168 } proto_msg; 169 struct tipc_msg *pmsg; 170 u32 priority; 171 u32 queue_limit[15]; /* queue_limit[0]==window limit */ 172 173 /* Changeover */ 174 u32 exp_msg_count; 175 u32 reset_checkpoint; 176 177 /* Max packet negotiation */ 178 u32 max_pkt; 179 u32 max_pkt_target; 180 u32 max_pkt_probes; 181 182 /* Sending */ 183 u32 out_queue_size; 184 struct sk_buff *first_out; 185 struct sk_buff *last_out; 186 u32 next_out_no; 187 u32 last_retransmitted; 188 u32 stale_count; 189 190 /* Reception */ 191 u32 next_in_no; 192 u32 deferred_inqueue_sz; 193 struct sk_buff *oldest_deferred_in; 194 struct sk_buff *newest_deferred_in; 195 u32 unacked_window; 196 197 /* Congestion handling */ 198 struct sk_buff *proto_msg_queue; 199 u32 retransm_queue_size; 200 u32 retransm_queue_head; 201 struct sk_buff *next_out; 202 struct list_head waiting_ports; 203 204 /* Fragmentation/reassembly */ 205 u32 long_msg_seq_no; 206 struct sk_buff *reasm_head; 207 struct sk_buff *reasm_tail; 208 209 /* Statistics */ 210 struct tipc_stats stats; 211 }; 212 213 struct tipc_port; 214 215 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, 216 struct tipc_bearer *b_ptr, 217 const struct tipc_media_addr *media_addr); 218 void tipc_link_delete(struct tipc_link *l_ptr); 219 void tipc_link_failover_send_queue(struct tipc_link *l_ptr); 220 void tipc_link_dup_send_queue(struct tipc_link *l_ptr, 221 struct tipc_link *dest); 222 void tipc_link_reset_fragments(struct tipc_link *l_ptr); 223 int tipc_link_is_up(struct tipc_link *l_ptr); 224 int tipc_link_is_active(struct tipc_link *l_ptr); 225 void tipc_link_purge_queues(struct tipc_link *l_ptr); 226 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, 227 int req_tlv_space, 228 u16 cmd); 229 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, 230 int req_tlv_space); 231 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, 232 int req_tlv_space); 233 void tipc_link_reset(struct tipc_link *l_ptr); 234 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector); 235 void tipc_link_send_names(struct list_head *message_list, u32 dest); 236 int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf); 237 u32 tipc_link_get_max_pkt(u32 dest, u32 selector); 238 int tipc_link_send_sections_fast(struct tipc_port *sender, 239 struct iovec const *msg_sect, 240 unsigned int len, u32 destnode); 241 void tipc_link_recv_bundle(struct sk_buff *buf); 242 int tipc_link_recv_fragment(struct sk_buff **reasm_head, 243 struct sk_buff **reasm_tail, 244 struct sk_buff **fbuf); 245 void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ, int prob, 246 u32 gap, u32 tolerance, u32 priority, 247 u32 acked_mtu); 248 void tipc_link_push_queue(struct tipc_link *l_ptr); 249 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail, 250 struct sk_buff *buf); 251 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all); 252 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 253 void tipc_link_retransmit(struct tipc_link *l_ptr, 254 struct sk_buff *start, u32 retransmits); 255 256 /* 257 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 258 */ 259 static inline u32 buf_seqno(struct sk_buff *buf) 260 { 261 return msg_seqno(buf_msg(buf)); 262 } 263 264 static inline u32 mod(u32 x) 265 { 266 return x & 0xffffu; 267 } 268 269 static inline int between(u32 lower, u32 upper, u32 n) 270 { 271 if ((lower < n) && (n < upper)) 272 return 1; 273 if ((upper < lower) && ((n > lower) || (n < upper))) 274 return 1; 275 return 0; 276 } 277 278 static inline int less_eq(u32 left, u32 right) 279 { 280 return mod(right - left) < 32768u; 281 } 282 283 static inline int less(u32 left, u32 right) 284 { 285 return less_eq(left, right) && (mod(right) != mod(left)); 286 } 287 288 static inline u32 lesser(u32 left, u32 right) 289 { 290 return less_eq(left, right) ? left : right; 291 } 292 293 294 /* 295 * Link status checking routines 296 */ 297 static inline int link_working_working(struct tipc_link *l_ptr) 298 { 299 return l_ptr->state == WORKING_WORKING; 300 } 301 302 static inline int link_working_unknown(struct tipc_link *l_ptr) 303 { 304 return l_ptr->state == WORKING_UNKNOWN; 305 } 306 307 static inline int link_reset_unknown(struct tipc_link *l_ptr) 308 { 309 return l_ptr->state == RESET_UNKNOWN; 310 } 311 312 static inline int link_reset_reset(struct tipc_link *l_ptr) 313 { 314 return l_ptr->state == RESET_RESET; 315 } 316 317 static inline int link_congested(struct tipc_link *l_ptr) 318 { 319 return l_ptr->out_queue_size >= l_ptr->queue_limit[0]; 320 } 321 322 #endif 323