2 * net/tipc/link.h: Include file for TIPC link code
4 * Copyright (c) 1995-2006, 2013-2014, Ericsson AB
5 * Copyright (c) 2004-2005, 2010-2011, Wind River Systems
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40 #include <net/genetlink.h>
44 /* Out-of-range value for link sequence numbers
46 #define INVALID_LINK_SEQ 0x10000
48 /* Link working states
50 #define WORKING_WORKING 560810u
51 #define WORKING_UNKNOWN 560811u
52 #define RESET_UNKNOWN 560812u
53 #define RESET_RESET 560813u
55 /* Link endpoint execution states
57 #define LINK_STARTED 0x0001
58 #define LINK_STOPPED 0x0002
60 /* Starting value for maximum packet size negotiation on unicast links
61 * (unless bearer MTU is less)
63 #define MAX_PKT_DEFAULT 1500
66 u32 sent_info; /* used in counting # sent packets */
67 u32 recv_info; /* used in counting # recv'd packets */
84 u32 link_congs; /* # port sends blocked by congestion */
87 u32 max_queue_sz; /* send queue size high water mark */
88 u32 accu_queue_sz; /* used for send queue size profiling */
89 u32 queue_sz_counts; /* used for send queue size profiling */
90 u32 msg_length_counts; /* used for message length profiling */
91 u32 msg_lengths_total; /* used for message length profiling */
92 u32 msg_length_profile[7]; /* used for msg. length profiling */
96 * struct tipc_link - TIPC link data structure
97 * @addr: network address of link's peer node
98 * @name: link name character string
99 * @media_addr: media address to use when sending messages over link
101 * @owner: pointer to peer node
102 * @flags: execution state flags for link endpoint instance
103 * @checkpoint: reference point for triggering link continuity checking
104 * @peer_session: link session # being used by peer end of link
105 * @peer_bearer_id: bearer id used by link's peer endpoint
106 * @bearer_id: local bearer id used by link
107 * @tolerance: minimum link continuity loss needed to reset link [in ms]
108 * @continuity_interval: link continuity testing interval [in ms]
109 * @abort_limit: # of unacknowledged continuity probes needed to reset link
110 * @state: current state of link FSM
111 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
112 * @proto_msg: template for control messages generated by link
113 * @pmsg: convenience pointer to "proto_msg" field
114 * @priority: current link priority
115 * @net_plane: current link network plane ('A' through 'H')
116 * @queue_limit: outbound message queue congestion thresholds (indexed by user)
117 * @exp_msg_count: # of tunnelled messages expected during link changeover
118 * @reset_checkpoint: seq # of last acknowledged message at time of link reset
119 * @max_pkt: current maximum packet size for this link
120 * @max_pkt_target: desired maximum packet size for this link
121 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
122 * @out_queue_size: # of messages in outbound message queue
123 * @first_out: ptr to first outbound message in queue
124 * @last_out: ptr to last outbound message in queue
125 * @next_out_no: next sequence number to use for outbound messages
126 * @last_retransmitted: sequence number of most recently retransmitted message
127 * @stale_count: # of identical retransmit requests made by peer
128 * @next_in_no: next sequence number to expect for inbound messages
129 * @deferred_inqueue_sz: # of messages in inbound message queue
130 * @oldest_deferred_in: ptr to first inbound message in queue
131 * @newest_deferred_in: ptr to last inbound message in queue
132 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
133 * @proto_msg_queue: ptr to (single) outbound control message
134 * @retransm_queue_size: number of messages to retransmit
135 * @retransm_queue_head: sequence number of first message to retransmit
136 * @next_out: ptr to first unsent outbound message in queue
137 * @waiting_sks: linked list of sockets 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
144 char name[TIPC_MAX_LINK_NAME];
145 struct tipc_media_addr media_addr;
146 struct timer_list timer;
147 struct tipc_node *owner;
149 /* Management and link supervision data */
156 u32 continuity_interval;
161 unchar hdr[INT_H_SIZE];
162 unchar body[TIPC_MAX_IF_NAME];
164 struct tipc_msg *pmsg;
167 u32 queue_limit[15]; /* queue_limit[0]==window limit */
171 u32 reset_checkpoint;
173 /* Max packet negotiation */
180 struct sk_buff *first_out;
181 struct sk_buff *last_out;
183 u32 last_retransmitted;
188 u32 deferred_inqueue_sz;
189 struct sk_buff *oldest_deferred_in;
190 struct sk_buff *newest_deferred_in;
193 /* Congestion handling */
194 struct sk_buff *proto_msg_queue;
195 u32 retransm_queue_size;
196 u32 retransm_queue_head;
197 struct sk_buff *next_out;
198 struct sk_buff_head waiting_sks;
200 /* Fragmentation/reassembly */
202 struct sk_buff *reasm_buf;
205 struct tipc_stats stats;
210 struct tipc_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_list(unsigned int bearer_id, bool shutting_down);
214 void tipc_link_failover_send_queue(struct tipc_link *l_ptr);
215 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr, struct tipc_link *dest);
216 void tipc_link_reset_fragments(struct tipc_link *l_ptr);
217 int tipc_link_is_up(struct tipc_link *l_ptr);
218 int tipc_link_is_active(struct tipc_link *l_ptr);
219 void tipc_link_purge_queues(struct tipc_link *l_ptr);
220 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area,
223 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area,
225 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area,
227 void tipc_link_reset_all(struct tipc_node *node);
228 void tipc_link_reset(struct tipc_link *l_ptr);
229 void tipc_link_reset_list(unsigned int bearer_id);
230 int tipc_link_xmit(struct sk_buff *buf, u32 dest, u32 selector);
231 int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf);
232 u32 tipc_link_get_max_pkt(u32 dest, u32 selector);
233 void tipc_link_bundle_rcv(struct sk_buff *buf);
234 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int prob,
235 u32 gap, u32 tolerance, u32 priority, u32 acked_mtu);
236 void tipc_link_push_queue(struct tipc_link *l_ptr);
237 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
238 struct sk_buff *buf);
239 void tipc_link_set_queue_limits(struct tipc_link *l_ptr, u32 window);
240 void tipc_link_retransmit(struct tipc_link *l_ptr,
241 struct sk_buff *start, u32 retransmits);
243 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
244 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info);
245 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info);
246 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]);
249 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
251 static inline u32 buf_seqno(struct sk_buff *buf)
253 return msg_seqno(buf_msg(buf));
256 static inline u32 mod(u32 x)
261 static inline int between(u32 lower, u32 upper, u32 n)
263 if ((lower < n) && (n < upper))
265 if ((upper < lower) && ((n > lower) || (n < upper)))
270 static inline int less_eq(u32 left, u32 right)
272 return mod(right - left) < 32768u;
275 static inline int less(u32 left, u32 right)
277 return less_eq(left, right) && (mod(right) != mod(left));
280 static inline u32 lesser(u32 left, u32 right)
282 return less_eq(left, right) ? left : right;
287 * Link status checking routines
289 static inline int link_working_working(struct tipc_link *l_ptr)
291 return l_ptr->state == WORKING_WORKING;
294 static inline int link_working_unknown(struct tipc_link *l_ptr)
296 return l_ptr->state == WORKING_UNKNOWN;
299 static inline int link_reset_unknown(struct tipc_link *l_ptr)
301 return l_ptr->state == RESET_UNKNOWN;
304 static inline int link_reset_reset(struct tipc_link *l_ptr)
306 return l_ptr->state == RESET_RESET;
309 static inline int link_congested(struct tipc_link *l_ptr)
311 return l_ptr->out_queue_size >= l_ptr->queue_limit[0];