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 * Out-of-range value for link sequence numbers 45 */ 46 #define INVALID_LINK_SEQ 0x10000 47 48 /* 49 * Link states 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 #define MAX_PKT_DEFAULT 1500 61 62 struct tipc_stats { 63 u32 sent_info; /* used in counting # sent packets */ 64 u32 recv_info; /* used in counting # recv'd packets */ 65 u32 sent_states; 66 u32 recv_states; 67 u32 sent_probes; 68 u32 recv_probes; 69 u32 sent_nacks; 70 u32 recv_nacks; 71 u32 sent_acks; 72 u32 sent_bundled; 73 u32 sent_bundles; 74 u32 recv_bundled; 75 u32 recv_bundles; 76 u32 retransmitted; 77 u32 sent_fragmented; 78 u32 sent_fragments; 79 u32 recv_fragmented; 80 u32 recv_fragments; 81 u32 link_congs; /* # port sends blocked by congestion */ 82 u32 deferred_recv; 83 u32 duplicates; 84 u32 max_queue_sz; /* send queue size high water mark */ 85 u32 accu_queue_sz; /* used for send queue size profiling */ 86 u32 queue_sz_counts; /* used for send queue size profiling */ 87 u32 msg_length_counts; /* used for message length profiling */ 88 u32 msg_lengths_total; /* used for message length profiling */ 89 u32 msg_length_profile[7]; /* used for msg. length profiling */ 90 }; 91 92 /** 93 * struct tipc_link - TIPC link data structure 94 * @addr: network address of link's peer node 95 * @name: link name character string 96 * @media_addr: media address to use when sending messages over link 97 * @timer: link timer 98 * @owner: pointer to peer node 99 * @link_list: adjacent links in bearer's list of links 100 * @started: indicates if link has been started 101 * @checkpoint: reference point for triggering link continuity checking 102 * @peer_session: link session # being used by peer end of link 103 * @peer_bearer_id: bearer id used by link's peer endpoint 104 * @b_ptr: pointer to bearer used by link 105 * @tolerance: minimum link continuity loss needed to reset link [in ms] 106 * @continuity_interval: link continuity testing interval [in ms] 107 * @abort_limit: # of unacknowledged continuity probes needed to reset link 108 * @state: current state of link FSM 109 * @blocked: indicates if link has been administratively blocked 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 * @queue_limit: outbound message queue congestion thresholds (indexed by user) 115 * @exp_msg_count: # of tunnelled messages expected during link changeover 116 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 117 * @max_pkt: current maximum packet size for this link 118 * @max_pkt_target: desired maximum packet size for this link 119 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target) 120 * @out_queue_size: # of messages in outbound message queue 121 * @first_out: ptr to first outbound message in queue 122 * @last_out: ptr to last outbound message in queue 123 * @next_out_no: next sequence number to use for outbound messages 124 * @last_retransmitted: sequence number of most recently retransmitted message 125 * @stale_count: # of identical retransmit requests made by peer 126 * @next_in_no: next sequence number to expect for inbound messages 127 * @deferred_inqueue_sz: # of messages in inbound message queue 128 * @oldest_deferred_in: ptr to first inbound message in queue 129 * @newest_deferred_in: ptr to last inbound message in queue 130 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 131 * @proto_msg_queue: ptr to (single) outbound control message 132 * @retransm_queue_size: number of messages to retransmit 133 * @retransm_queue_head: sequence number of first message to retransmit 134 * @next_out: ptr to first unsent outbound message in queue 135 * @waiting_ports: linked list of ports waiting for link congestion to abate 136 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 137 * @defragm_buf: list of partially reassembled inbound message fragments 138 * @stats: collects statistics regarding link activity 139 */ 140 struct tipc_link { 141 u32 addr; 142 char name[TIPC_MAX_LINK_NAME]; 143 struct tipc_media_addr media_addr; 144 struct timer_list timer; 145 struct tipc_node *owner; 146 struct list_head link_list; 147 148 /* Management and link supervision data */ 149 int started; 150 u32 checkpoint; 151 u32 peer_session; 152 u32 peer_bearer_id; 153 struct tipc_bearer *b_ptr; 154 u32 tolerance; 155 u32 continuity_interval; 156 u32 abort_limit; 157 int state; 158 int blocked; 159 u32 fsm_msg_cnt; 160 struct { 161 unchar hdr[INT_H_SIZE]; 162 unchar body[TIPC_MAX_IF_NAME]; 163 } proto_msg; 164 struct tipc_msg *pmsg; 165 u32 priority; 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 list_head waiting_ports; 198 199 /* Fragmentation/defragmentation */ 200 u32 long_msg_seq_no; 201 struct sk_buff *defragm_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(struct tipc_link *l_ptr); 213 void tipc_link_changeover(struct tipc_link *l_ptr); 214 void tipc_link_send_duplicate(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 u32 tipc_link_push_packet(struct tipc_link *l_ptr); 219 void tipc_link_stop(struct tipc_link *l_ptr); 220 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd); 221 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space); 222 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space); 223 void tipc_link_reset(struct tipc_link *l_ptr); 224 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector); 225 void tipc_link_send_names(struct list_head *message_list, u32 dest); 226 int tipc_link_send_buf(struct tipc_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 unsigned int total_len, 232 u32 destnode); 233 void tipc_link_recv_bundle(struct sk_buff *buf); 234 int tipc_link_recv_fragment(struct sk_buff **pending, 235 struct sk_buff **fb, 236 struct tipc_msg **msg); 237 void tipc_link_send_proto_msg(struct tipc_link *l_ptr, u32 msg_typ, int prob, 238 u32 gap, u32 tolerance, u32 priority, 239 u32 acked_mtu); 240 void tipc_link_push_queue(struct tipc_link *l_ptr); 241 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail, 242 struct sk_buff *buf); 243 void tipc_link_wakeup_ports(struct tipc_link *l_ptr, int all); 244 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 245 void tipc_link_retransmit(struct tipc_link *l_ptr, 246 struct sk_buff *start, u32 retransmits); 247 248 /* 249 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 250 */ 251 static inline u32 buf_seqno(struct sk_buff *buf) 252 { 253 return msg_seqno(buf_msg(buf)); 254 } 255 256 static inline u32 mod(u32 x) 257 { 258 return x & 0xffffu; 259 } 260 261 static inline int between(u32 lower, u32 upper, u32 n) 262 { 263 if ((lower < n) && (n < upper)) 264 return 1; 265 if ((upper < lower) && ((n > lower) || (n < upper))) 266 return 1; 267 return 0; 268 } 269 270 static inline int less_eq(u32 left, u32 right) 271 { 272 return mod(right - left) < 32768u; 273 } 274 275 static inline int less(u32 left, u32 right) 276 { 277 return less_eq(left, right) && (mod(right) != mod(left)); 278 } 279 280 static inline u32 lesser(u32 left, u32 right) 281 { 282 return less_eq(left, right) ? left : right; 283 } 284 285 286 /* 287 * Link status checking routines 288 */ 289 static inline int link_working_working(struct tipc_link *l_ptr) 290 { 291 return l_ptr->state == WORKING_WORKING; 292 } 293 294 static inline int link_working_unknown(struct tipc_link *l_ptr) 295 { 296 return l_ptr->state == WORKING_UNKNOWN; 297 } 298 299 static inline int link_reset_unknown(struct tipc_link *l_ptr) 300 { 301 return l_ptr->state == RESET_UNKNOWN; 302 } 303 304 static inline int link_reset_reset(struct tipc_link *l_ptr) 305 { 306 return l_ptr->state == RESET_RESET; 307 } 308 309 static inline int link_blocked(struct tipc_link *l_ptr) 310 { 311 return l_ptr->exp_msg_count || l_ptr->blocked; 312 } 313 314 static inline int link_congested(struct tipc_link *l_ptr) 315 { 316 return l_ptr->out_queue_size >= l_ptr->queue_limit[0]; 317 } 318 319 #endif 320