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 "log.h" 41 #include "msg.h" 42 #include "node.h" 43 44 #define PUSH_FAILED 1 45 #define PUSH_FINISHED 2 46 47 /* 48 * Out-of-range value for link sequence numbers 49 */ 50 #define INVALID_LINK_SEQ 0x10000 51 52 /* 53 * Link states 54 */ 55 #define WORKING_WORKING 560810u 56 #define WORKING_UNKNOWN 560811u 57 #define RESET_UNKNOWN 560812u 58 #define RESET_RESET 560813u 59 60 /* 61 * Starting value for maximum packet size negotiation on unicast links 62 * (unless bearer MTU is less) 63 */ 64 #define MAX_PKT_DEFAULT 1500 65 66 /** 67 * struct tipc_link - TIPC link data structure 68 * @addr: network address of link's peer node 69 * @name: link name character string 70 * @media_addr: media address to use when sending messages over link 71 * @timer: link timer 72 * @owner: pointer to peer node 73 * @link_list: adjacent links in bearer's list of links 74 * @started: indicates if link has been started 75 * @checkpoint: reference point for triggering link continuity checking 76 * @peer_session: link session # being used by peer end of link 77 * @peer_bearer_id: bearer id used by link's peer endpoint 78 * @b_ptr: pointer to bearer used by link 79 * @tolerance: minimum link continuity loss needed to reset link [in ms] 80 * @continuity_interval: link continuity testing interval [in ms] 81 * @abort_limit: # of unacknowledged continuity probes needed to reset link 82 * @state: current state of link FSM 83 * @blocked: indicates if link has been administratively blocked 84 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state 85 * @proto_msg: template for control messages generated by link 86 * @pmsg: convenience pointer to "proto_msg" field 87 * @priority: current link priority 88 * @queue_limit: outbound message queue congestion thresholds (indexed by user) 89 * @exp_msg_count: # of tunnelled messages expected during link changeover 90 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 91 * @max_pkt: current maximum packet size for this link 92 * @max_pkt_target: desired maximum packet size for this link 93 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target) 94 * @out_queue_size: # of messages in outbound message queue 95 * @first_out: ptr to first outbound message in queue 96 * @last_out: ptr to last outbound message in queue 97 * @next_out_no: next sequence number to use for outbound messages 98 * @last_retransmitted: sequence number of most recently retransmitted message 99 * @stale_count: # of identical retransmit requests made by peer 100 * @next_in_no: next sequence number to expect for inbound messages 101 * @deferred_inqueue_sz: # of messages in inbound message queue 102 * @oldest_deferred_in: ptr to first inbound message in queue 103 * @newest_deferred_in: ptr to last inbound message in queue 104 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 105 * @proto_msg_queue: ptr to (single) outbound control message 106 * @retransm_queue_size: number of messages to retransmit 107 * @retransm_queue_head: sequence number of first message to retransmit 108 * @next_out: ptr to first unsent outbound message in queue 109 * @waiting_ports: linked list of ports waiting for link congestion to abate 110 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 111 * @defragm_buf: list of partially reassembled inbound message fragments 112 * @stats: collects statistics regarding link activity 113 */ 114 struct tipc_link { 115 u32 addr; 116 char name[TIPC_MAX_LINK_NAME]; 117 struct tipc_media_addr media_addr; 118 struct timer_list timer; 119 struct tipc_node *owner; 120 struct list_head link_list; 121 122 /* Management and link supervision data */ 123 int started; 124 u32 checkpoint; 125 u32 peer_session; 126 u32 peer_bearer_id; 127 struct tipc_bearer *b_ptr; 128 u32 tolerance; 129 u32 continuity_interval; 130 u32 abort_limit; 131 int state; 132 int blocked; 133 u32 fsm_msg_cnt; 134 struct { 135 unchar hdr[INT_H_SIZE]; 136 unchar body[TIPC_MAX_IF_NAME]; 137 } proto_msg; 138 struct tipc_msg *pmsg; 139 u32 priority; 140 u32 queue_limit[15]; /* queue_limit[0]==window limit */ 141 142 /* Changeover */ 143 u32 exp_msg_count; 144 u32 reset_checkpoint; 145 146 /* Max packet negotiation */ 147 u32 max_pkt; 148 u32 max_pkt_target; 149 u32 max_pkt_probes; 150 151 /* Sending */ 152 u32 out_queue_size; 153 struct sk_buff *first_out; 154 struct sk_buff *last_out; 155 u32 next_out_no; 156 u32 last_retransmitted; 157 u32 stale_count; 158 159 /* Reception */ 160 u32 next_in_no; 161 u32 deferred_inqueue_sz; 162 struct sk_buff *oldest_deferred_in; 163 struct sk_buff *newest_deferred_in; 164 u32 unacked_window; 165 166 /* Congestion handling */ 167 struct sk_buff *proto_msg_queue; 168 u32 retransm_queue_size; 169 u32 retransm_queue_head; 170 struct sk_buff *next_out; 171 struct list_head waiting_ports; 172 173 /* Fragmentation/defragmentation */ 174 u32 long_msg_seq_no; 175 struct sk_buff *defragm_buf; 176 177 /* Statistics */ 178 struct { 179 u32 sent_info; /* used in counting # sent packets */ 180 u32 recv_info; /* used in counting # recv'd packets */ 181 u32 sent_states; 182 u32 recv_states; 183 u32 sent_probes; 184 u32 recv_probes; 185 u32 sent_nacks; 186 u32 recv_nacks; 187 u32 sent_acks; 188 u32 sent_bundled; 189 u32 sent_bundles; 190 u32 recv_bundled; 191 u32 recv_bundles; 192 u32 retransmitted; 193 u32 sent_fragmented; 194 u32 sent_fragments; 195 u32 recv_fragmented; 196 u32 recv_fragments; 197 u32 link_congs; /* # port sends blocked by congestion */ 198 u32 bearer_congs; 199 u32 deferred_recv; 200 u32 duplicates; 201 u32 max_queue_sz; /* send queue size high water mark */ 202 u32 accu_queue_sz; /* used for send queue size profiling */ 203 u32 queue_sz_counts; /* used for send queue size profiling */ 204 u32 msg_length_counts; /* used for message length profiling */ 205 u32 msg_lengths_total; /* used for message length profiling */ 206 u32 msg_length_profile[7]; /* used for msg. length profiling */ 207 } stats; 208 }; 209 210 struct tipc_port; 211 212 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, 213 struct tipc_bearer *b_ptr, 214 const struct tipc_media_addr *media_addr); 215 void tipc_link_delete(struct tipc_link *l_ptr); 216 void tipc_link_changeover(struct tipc_link *l_ptr); 217 void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *dest); 218 void tipc_link_reset_fragments(struct tipc_link *l_ptr); 219 int tipc_link_is_up(struct tipc_link *l_ptr); 220 int tipc_link_is_active(struct tipc_link *l_ptr); 221 u32 tipc_link_push_packet(struct tipc_link *l_ptr); 222 void tipc_link_stop(struct tipc_link *l_ptr); 223 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd); 224 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space); 225 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space); 226 void tipc_link_reset(struct tipc_link *l_ptr); 227 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector); 228 void tipc_link_send_names(struct list_head *message_list, u32 dest); 229 int tipc_link_send_buf(struct tipc_link *l_ptr, struct sk_buff *buf); 230 u32 tipc_link_get_max_pkt(u32 dest, u32 selector); 231 int tipc_link_send_sections_fast(struct tipc_port *sender, 232 struct iovec const *msg_sect, 233 const u32 num_sect, 234 unsigned int total_len, 235 u32 destnode); 236 void tipc_link_recv_bundle(struct sk_buff *buf); 237 int tipc_link_recv_fragment(struct sk_buff **pending, 238 struct sk_buff **fb, 239 struct tipc_msg **msg); 240 void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ, int prob, 241 u32 gap, u32 tolerance, u32 priority, 242 u32 acked_mtu); 243 void tipc_link_push_queue(struct tipc_link *l_ptr); 244 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail, 245 struct sk_buff *buf); 246 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all); 247 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 248 void tipc_link_retransmit(struct tipc_link *l_ptr, 249 struct sk_buff *start, u32 retransmits); 250 251 /* 252 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 253 */ 254 static inline u32 buf_seqno(struct sk_buff *buf) 255 { 256 return msg_seqno(buf_msg(buf)); 257 } 258 259 static inline u32 mod(u32 x) 260 { 261 return x & 0xffffu; 262 } 263 264 static inline int between(u32 lower, u32 upper, u32 n) 265 { 266 if ((lower < n) && (n < upper)) 267 return 1; 268 if ((upper < lower) && ((n > lower) || (n < upper))) 269 return 1; 270 return 0; 271 } 272 273 static inline int less_eq(u32 left, u32 right) 274 { 275 return mod(right - left) < 32768u; 276 } 277 278 static inline int less(u32 left, u32 right) 279 { 280 return less_eq(left, right) && (mod(right) != mod(left)); 281 } 282 283 static inline u32 lesser(u32 left, u32 right) 284 { 285 return less_eq(left, right) ? left : right; 286 } 287 288 289 /* 290 * Link status checking routines 291 */ 292 static inline int link_working_working(struct tipc_link *l_ptr) 293 { 294 return l_ptr->state == WORKING_WORKING; 295 } 296 297 static inline int link_working_unknown(struct tipc_link *l_ptr) 298 { 299 return l_ptr->state == WORKING_UNKNOWN; 300 } 301 302 static inline int link_reset_unknown(struct tipc_link *l_ptr) 303 { 304 return l_ptr->state == RESET_UNKNOWN; 305 } 306 307 static inline int link_reset_reset(struct tipc_link *l_ptr) 308 { 309 return l_ptr->state == RESET_RESET; 310 } 311 312 static inline int link_blocked(struct tipc_link *l_ptr) 313 { 314 return l_ptr->exp_msg_count || l_ptr->blocked; 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