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 <net/genetlink.h> 41 #include "msg.h" 42 #include "node.h" 43 44 /* TIPC-specific error codes 45 */ 46 #define ELINKCONG EAGAIN /* link congestion <=> resource unavailable */ 47 48 /* Out-of-range value for link sequence numbers 49 */ 50 #define INVALID_LINK_SEQ 0x10000 51 52 /* Link working states 53 */ 54 #define WORKING_WORKING 560810u 55 #define WORKING_UNKNOWN 560811u 56 #define RESET_UNKNOWN 560812u 57 #define RESET_RESET 560813u 58 59 /* Link endpoint execution states 60 */ 61 #define LINK_STARTED 0x0001 62 #define LINK_STOPPED 0x0002 63 64 /* Starting value for maximum packet size negotiation on unicast links 65 * (unless bearer MTU is less) 66 */ 67 #define MAX_PKT_DEFAULT 1500 68 69 struct tipc_stats { 70 u32 sent_info; /* used in counting # sent packets */ 71 u32 recv_info; /* used in counting # recv'd packets */ 72 u32 sent_states; 73 u32 recv_states; 74 u32 sent_probes; 75 u32 recv_probes; 76 u32 sent_nacks; 77 u32 recv_nacks; 78 u32 sent_acks; 79 u32 sent_bundled; 80 u32 sent_bundles; 81 u32 recv_bundled; 82 u32 recv_bundles; 83 u32 retransmitted; 84 u32 sent_fragmented; 85 u32 sent_fragments; 86 u32 recv_fragmented; 87 u32 recv_fragments; 88 u32 link_congs; /* # port sends blocked by congestion */ 89 u32 deferred_recv; 90 u32 duplicates; 91 u32 max_queue_sz; /* send queue size high water mark */ 92 u32 accu_queue_sz; /* used for send queue size profiling */ 93 u32 queue_sz_counts; /* used for send queue size profiling */ 94 u32 msg_length_counts; /* used for message length profiling */ 95 u32 msg_lengths_total; /* used for message length profiling */ 96 u32 msg_length_profile[7]; /* used for msg. length profiling */ 97 }; 98 99 /** 100 * struct tipc_link - TIPC link data structure 101 * @addr: network address of link's peer node 102 * @name: link name character string 103 * @media_addr: media address to use when sending messages over link 104 * @timer: link timer 105 * @owner: pointer to peer node 106 * @refcnt: reference counter for permanent references (owner node & timer) 107 * @flags: execution state flags for link endpoint instance 108 * @checkpoint: reference point for triggering link continuity checking 109 * @peer_session: link session # being used by peer end of link 110 * @peer_bearer_id: bearer id used by link's peer endpoint 111 * @bearer_id: local bearer id used by link 112 * @tolerance: minimum link continuity loss needed to reset link [in ms] 113 * @cont_intv: link continuity testing interval 114 * @abort_limit: # of unacknowledged continuity probes needed to reset link 115 * @state: current state of link FSM 116 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state 117 * @proto_msg: template for control messages generated by link 118 * @pmsg: convenience pointer to "proto_msg" field 119 * @priority: current link priority 120 * @net_plane: current link network plane ('A' through 'H') 121 * @queue_limit: outbound message queue congestion thresholds (indexed by user) 122 * @exp_msg_count: # of tunnelled messages expected during link changeover 123 * @reset_checkpoint: seq # of last acknowledged message at time of link reset 124 * @max_pkt: current maximum packet size for this link 125 * @max_pkt_target: desired maximum packet size for this link 126 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target) 127 * @outqueue: outbound message 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_queue: deferred queue saved OOS b'cast message received from node 133 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer 134 * @inputq: buffer queue for messages to be delivered upwards 135 * @namedq: buffer queue for name table messages to be delivered upwards 136 * @next_out: ptr to first unsent outbound message in queue 137 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate 138 * @long_msg_seq_no: next identifier to use for outbound fragmented messages 139 * @reasm_buf: head of partially reassembled inbound message fragments 140 * @stats: collects statistics regarding link activity 141 */ 142 struct tipc_link { 143 u32 addr; 144 char name[TIPC_MAX_LINK_NAME]; 145 struct tipc_media_addr media_addr; 146 struct timer_list timer; 147 struct tipc_node *owner; 148 struct kref ref; 149 150 /* Management and link supervision data */ 151 unsigned int flags; 152 u32 checkpoint; 153 u32 peer_session; 154 u32 peer_bearer_id; 155 u32 bearer_id; 156 u32 tolerance; 157 unsigned long cont_intv; 158 u32 abort_limit; 159 int state; 160 u32 fsm_msg_cnt; 161 struct { 162 unchar hdr[INT_H_SIZE]; 163 unchar body[TIPC_MAX_IF_NAME]; 164 } proto_msg; 165 struct tipc_msg *pmsg; 166 u32 priority; 167 char net_plane; 168 u32 queue_limit[15]; /* queue_limit[0]==window limit */ 169 170 /* Changeover */ 171 u32 exp_msg_count; 172 u32 reset_checkpoint; 173 174 /* Max packet negotiation */ 175 u32 max_pkt; 176 u32 max_pkt_target; 177 u32 max_pkt_probes; 178 179 /* Sending */ 180 struct sk_buff_head outqueue; 181 u32 next_out_no; 182 u32 last_retransmitted; 183 u32 stale_count; 184 185 /* Reception */ 186 u32 next_in_no; 187 struct sk_buff_head deferred_queue; 188 u32 unacked_window; 189 struct sk_buff_head inputq; 190 struct sk_buff_head namedq; 191 192 /* Congestion handling */ 193 struct sk_buff *next_out; 194 struct sk_buff_head wakeupq; 195 196 /* Fragmentation/reassembly */ 197 u32 long_msg_seq_no; 198 struct sk_buff *reasm_buf; 199 200 /* Statistics */ 201 struct tipc_stats stats; 202 }; 203 204 struct tipc_port; 205 206 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr, 207 struct tipc_bearer *b_ptr, 208 const struct tipc_media_addr *media_addr); 209 void tipc_link_delete(struct tipc_link *link); 210 void tipc_link_delete_list(struct net *net, unsigned int bearer_id, 211 bool shutting_down); 212 void tipc_link_failover_send_queue(struct tipc_link *l_ptr); 213 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr, struct tipc_link *dest); 214 void tipc_link_reset_fragments(struct tipc_link *l_ptr); 215 int tipc_link_is_up(struct tipc_link *l_ptr); 216 int tipc_link_is_active(struct tipc_link *l_ptr); 217 void tipc_link_purge_queues(struct tipc_link *l_ptr); 218 void tipc_link_reset_all(struct tipc_node *node); 219 void tipc_link_reset(struct tipc_link *l_ptr); 220 void tipc_link_reset_list(struct net *net, unsigned int bearer_id); 221 int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest, 222 u32 selector); 223 int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dest, 224 u32 selector); 225 int __tipc_link_xmit(struct net *net, struct tipc_link *link, 226 struct sk_buff_head *list); 227 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob, 228 u32 gap, u32 tolerance, u32 priority, u32 acked_mtu); 229 void tipc_link_push_packets(struct tipc_link *l_ptr); 230 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *buf); 231 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window); 232 void tipc_link_retransmit(struct tipc_link *l_ptr, 233 struct sk_buff *start, u32 retransmits); 234 struct sk_buff *tipc_skb_queue_next(const struct sk_buff_head *list, 235 const struct sk_buff *skb); 236 237 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb); 238 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info); 239 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info); 240 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info); 241 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]); 242 void link_prepare_wakeup(struct tipc_link *l); 243 244 /* 245 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic) 246 */ 247 static inline u32 buf_seqno(struct sk_buff *buf) 248 { 249 return msg_seqno(buf_msg(buf)); 250 } 251 252 static inline u32 mod(u32 x) 253 { 254 return x & 0xffffu; 255 } 256 257 static inline int less_eq(u32 left, u32 right) 258 { 259 return mod(right - left) < 32768u; 260 } 261 262 static inline int more(u32 left, u32 right) 263 { 264 return !less_eq(left, right); 265 } 266 267 static inline int less(u32 left, u32 right) 268 { 269 return less_eq(left, right) && (mod(right) != mod(left)); 270 } 271 272 static inline u32 lesser(u32 left, u32 right) 273 { 274 return less_eq(left, right) ? left : right; 275 } 276 277 static inline u32 link_own_addr(struct tipc_link *l) 278 { 279 return msg_prevnode(l->pmsg); 280 } 281 282 /* 283 * Link status checking routines 284 */ 285 static inline int link_working_working(struct tipc_link *l_ptr) 286 { 287 return l_ptr->state == WORKING_WORKING; 288 } 289 290 static inline int link_working_unknown(struct tipc_link *l_ptr) 291 { 292 return l_ptr->state == WORKING_UNKNOWN; 293 } 294 295 static inline int link_reset_unknown(struct tipc_link *l_ptr) 296 { 297 return l_ptr->state == RESET_UNKNOWN; 298 } 299 300 static inline int link_reset_reset(struct tipc_link *l_ptr) 301 { 302 return l_ptr->state == RESET_RESET; 303 } 304 305 static inline int link_congested(struct tipc_link *l_ptr) 306 { 307 return skb_queue_len(&l_ptr->outqueue) >= l_ptr->queue_limit[0]; 308 } 309 310 #endif 311