2 * net/tipc/link.h: Include file for TIPC link code
4 * Copyright (c) 1995-2006, Ericsson AB
5 * Copyright (c) 2004-2005, Wind River Systems
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46 #define PUSH_FINISHED 2
52 #define WORKING_WORKING 560810u
53 #define WORKING_UNKNOWN 560811u
54 #define RESET_UNKNOWN 560812u
55 #define RESET_RESET 560813u
58 * Starting value for maximum packet size negotiation on unicast links
59 * (unless bearer MTU is less)
62 #define MAX_PKT_DEFAULT 1500
65 * struct link - TIPC link data structure
66 * @addr: network address of link's peer node
67 * @name: link name character string
68 * @media_addr: media address to use when sending messages over link
70 * @owner: pointer to peer node
71 * @link_list: adjacent links in bearer's list of links
72 * @started: indicates if link has been started
73 * @checkpoint: reference point for triggering link continuity checking
74 * @peer_session: link session # being used by peer end of link
75 * @peer_bearer_id: bearer id used by link's peer endpoint
76 * @b_ptr: pointer to bearer used by link
77 * @tolerance: minimum link continuity loss needed to reset link [in ms]
78 * @continuity_interval: link continuity testing interval [in ms]
79 * @abort_limit: # of unacknowledged continuity probes needed to reset link
80 * @state: current state of link FSM
81 * @blocked: indicates if link has been administratively blocked
82 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
83 * @proto_msg: template for control messages generated by link
84 * @pmsg: convenience pointer to "proto_msg" field
85 * @priority: current link priority
86 * @queue_limit: outbound message queue congestion thresholds (indexed by user)
87 * @exp_msg_count: # of tunnelled messages expected during link changeover
88 * @reset_checkpoint: seq # of last acknowledged message at time of link reset
89 * @max_pkt: current maximum packet size for this link
90 * @max_pkt_target: desired maximum packet size for this link
91 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
92 * @out_queue_size: # of messages in outbound message queue
93 * @first_out: ptr to first outbound message in queue
94 * @last_out: ptr to last outbound message in queue
95 * @next_out_no: next sequence number to use for outbound messages
96 * @last_retransmitted: sequence number of most recently retransmitted message
97 * @stale_count: # of identical retransmit requests made by peer
98 * @next_in_no: next sequence number to expect for inbound messages
99 * @deferred_inqueue_sz: # of messages in inbound message queue
100 * @oldest_deferred_in: ptr to first inbound message in queue
101 * @newest_deferred_in: ptr to last inbound message in queue
102 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
103 * @proto_msg_queue: ptr to (single) outbound control message
104 * @retransm_queue_size: number of messages to retransmit
105 * @retransm_queue_head: sequence number of first message to retransmit
106 * @next_out: ptr to first unsent outbound message in queue
107 * @waiting_ports: linked list of ports waiting for link congestion to abate
108 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
109 * @defragm_buf: list of partially reassembled inbound message fragments
110 * @stats: collects statistics regarding link activity
111 * @print_buf: print buffer used to log link activity
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;
122 /* Management and link supervision data */
127 struct bearer *b_ptr;
129 u32 continuity_interval;
135 unchar hdr[INT_H_SIZE];
136 unchar body[TIPC_MAX_IF_NAME];
138 struct tipc_msg *pmsg;
140 u32 queue_limit[15]; /* queue_limit[0]==window limit */
144 u32 reset_checkpoint;
146 /* Max packet negotiation */
153 struct sk_buff *first_out;
154 struct sk_buff *last_out;
156 u32 last_retransmitted;
161 u32 deferred_inqueue_sz;
162 struct sk_buff *oldest_deferred_in;
163 struct sk_buff *newest_deferred_in;
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;
173 /* Fragmentation/defragmentation */
175 struct sk_buff *defragm_buf;
179 u32 sent_info; /* used in counting # sent packets */
180 u32 recv_info; /* used in counting # recv'd packets */
197 u32 link_congs; /* # port sends blocked by congestion */
202 /* for statistical profiling of send queue size */
208 /* for statistical profiling of message lengths */
210 u32 msg_length_counts;
211 u32 msg_lengths_total;
212 u32 msg_length_profile[7];
215 struct print_buf print_buf;
220 struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
221 const struct tipc_media_addr *media_addr);
222 void tipc_link_delete(struct link *l_ptr);
223 void tipc_link_changeover(struct link *l_ptr);
224 void tipc_link_send_duplicate(struct link *l_ptr, struct link *dest);
225 void tipc_link_reset_fragments(struct link *l_ptr);
226 int tipc_link_is_up(struct link *l_ptr);
227 int tipc_link_is_active(struct link *l_ptr);
228 u32 tipc_link_push_packet(struct link *l_ptr);
229 void tipc_link_stop(struct link *l_ptr);
230 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd);
231 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space);
232 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space);
233 void tipc_link_reset(struct link *l_ptr);
234 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector);
235 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf);
236 u32 tipc_link_get_max_pkt(u32 dest,u32 selector);
237 int tipc_link_send_sections_fast(struct port* sender,
238 struct iovec const *msg_sect,
241 void tipc_link_recv_bundle(struct sk_buff *buf);
242 int tipc_link_recv_fragment(struct sk_buff **pending,
244 struct tipc_msg **msg);
245 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int prob, u32 gap,
246 u32 tolerance, u32 priority, u32 acked_mtu);
247 void tipc_link_push_queue(struct link *l_ptr);
248 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
249 struct sk_buff *buf);
250 void tipc_link_wakeup_ports(struct link *l_ptr, int all);
251 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window);
252 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *start, u32 retransmits);
255 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
258 static inline u32 mod(u32 x)
263 static inline int between(u32 lower, u32 upper, u32 n)
265 if ((lower < n) && (n < upper))
267 if ((upper < lower) && ((n > lower) || (n < upper)))
272 static inline int less_eq(u32 left, u32 right)
274 return mod(right - left) < 32768u;
277 static inline int less(u32 left, u32 right)
279 return less_eq(left, right) && (mod(right) != mod(left));
282 static inline u32 lesser(u32 left, u32 right)
284 return less_eq(left, right) ? left : right;
289 * Link status checking routines
292 static inline int link_working_working(struct link *l_ptr)
294 return l_ptr->state == WORKING_WORKING;
297 static inline int link_working_unknown(struct link *l_ptr)
299 return l_ptr->state == WORKING_UNKNOWN;
302 static inline int link_reset_unknown(struct link *l_ptr)
304 return l_ptr->state == RESET_UNKNOWN;
307 static inline int link_reset_reset(struct link *l_ptr)
309 return l_ptr->state == RESET_RESET;
312 static inline int link_blocked(struct link *l_ptr)
314 return l_ptr->exp_msg_count || l_ptr->blocked;
317 static inline int link_congested(struct link *l_ptr)
319 return l_ptr->out_queue_size >= l_ptr->queue_limit[0];