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