2 * net/tipc/link.h: Include file for TIPC link code
4 * Copyright (c) 1995-2006, 2013, Ericsson AB
5 * Copyright (c) 2004-2005, 2010-2011, Wind River Systems
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21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
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43 /* Link reassembly status codes
45 #define LINK_REASM_ERROR -1
46 #define LINK_REASM_COMPLETE 1
48 /* Out-of-range value for link sequence numbers
50 #define INVALID_LINK_SEQ 0x10000
52 /* Link working states
54 #define WORKING_WORKING 560810u
55 #define WORKING_UNKNOWN 560811u
56 #define RESET_UNKNOWN 560812u
57 #define RESET_RESET 560813u
59 /* Link endpoint execution states
61 #define LINK_STARTED 0x0001
62 #define LINK_STOPPED 0x0002
64 /* Starting value for maximum packet size negotiation on unicast links
65 * (unless bearer MTU is less)
67 #define MAX_PKT_DEFAULT 1500
70 u32 sent_info
; /* used in counting # sent packets */
71 u32 recv_info
; /* used in counting # recv'd packets */
88 u32 link_congs
; /* # port sends blocked by congestion */
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 */
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
105 * @owner: pointer to peer node
106 * @flags: execution state flags for link endpoint instance
107 * @checkpoint: reference point for triggering link continuity checking
108 * @peer_session: link session # being used by peer end of link
109 * @peer_bearer_id: bearer id used by link's peer endpoint
110 * @b_ptr: pointer to bearer used by link
111 * @tolerance: minimum link continuity loss needed to reset link [in ms]
112 * @continuity_interval: link continuity testing interval [in ms]
113 * @abort_limit: # of unacknowledged continuity probes needed to reset link
114 * @state: current state of link FSM
115 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
116 * @proto_msg: template for control messages generated by link
117 * @pmsg: convenience pointer to "proto_msg" field
118 * @priority: current link priority
119 * @queue_limit: outbound message queue congestion thresholds (indexed by user)
120 * @exp_msg_count: # of tunnelled messages expected during link changeover
121 * @reset_checkpoint: seq # of last acknowledged message at time of link reset
122 * @max_pkt: current maximum packet size for this link
123 * @max_pkt_target: desired maximum packet size for this link
124 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
125 * @out_queue_size: # of messages in outbound message queue
126 * @first_out: ptr to first outbound message in queue
127 * @last_out: ptr to last outbound message in 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_inqueue_sz: # of messages in inbound message queue
133 * @oldest_deferred_in: ptr to first inbound message in queue
134 * @newest_deferred_in: ptr to last inbound message in queue
135 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
136 * @proto_msg_queue: ptr to (single) outbound control message
137 * @retransm_queue_size: number of messages to retransmit
138 * @retransm_queue_head: sequence number of first message to retransmit
139 * @next_out: ptr to first unsent outbound message in queue
140 * @waiting_ports: linked list of ports waiting for link congestion to abate
141 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
142 * @reasm_head: list head of partially reassembled inbound message fragments
143 * @reasm_tail: last fragment received
144 * @stats: collects statistics regarding link activity
148 char name
[TIPC_MAX_LINK_NAME
];
149 struct tipc_media_addr media_addr
;
150 struct timer_list timer
;
151 struct tipc_node
*owner
;
153 /* Management and link supervision data */
158 struct tipc_bearer
*b_ptr
;
160 u32 continuity_interval
;
165 unchar hdr
[INT_H_SIZE
];
166 unchar body
[TIPC_MAX_IF_NAME
];
168 struct tipc_msg
*pmsg
;
170 u32 queue_limit
[15]; /* queue_limit[0]==window limit */
174 u32 reset_checkpoint
;
176 /* Max packet negotiation */
183 struct sk_buff
*first_out
;
184 struct sk_buff
*last_out
;
186 u32 last_retransmitted
;
191 u32 deferred_inqueue_sz
;
192 struct sk_buff
*oldest_deferred_in
;
193 struct sk_buff
*newest_deferred_in
;
196 /* Congestion handling */
197 struct sk_buff
*proto_msg_queue
;
198 u32 retransm_queue_size
;
199 u32 retransm_queue_head
;
200 struct sk_buff
*next_out
;
201 struct list_head waiting_ports
;
203 /* Fragmentation/reassembly */
205 struct sk_buff
*reasm_head
;
206 struct sk_buff
*reasm_tail
;
209 struct tipc_stats stats
;
214 struct tipc_link
*tipc_link_create(struct tipc_node
*n_ptr
,
215 struct tipc_bearer
*b_ptr
,
216 const struct tipc_media_addr
*media_addr
);
217 void tipc_link_delete_list(unsigned int bearer_id
, bool shutting_down
);
218 void tipc_link_failover_send_queue(struct tipc_link
*l_ptr
);
219 void tipc_link_dup_queue_xmit(struct tipc_link
*l_ptr
, struct tipc_link
*dest
);
220 void tipc_link_reset_fragments(struct tipc_link
*l_ptr
);
221 int tipc_link_is_up(struct tipc_link
*l_ptr
);
222 int tipc_link_is_active(struct tipc_link
*l_ptr
);
223 void tipc_link_purge_queues(struct tipc_link
*l_ptr
);
224 struct sk_buff
*tipc_link_cmd_config(const void *req_tlv_area
,
227 struct sk_buff
*tipc_link_cmd_show_stats(const void *req_tlv_area
,
229 struct sk_buff
*tipc_link_cmd_reset_stats(const void *req_tlv_area
,
231 void tipc_link_reset(struct tipc_link
*l_ptr
);
232 void tipc_link_reset_list(unsigned int bearer_id
);
233 int tipc_link_xmit(struct sk_buff
*buf
, u32 dest
, u32 selector
);
234 void tipc_link_names_xmit(struct list_head
*message_list
, u32 dest
);
235 int __tipc_link_xmit(struct tipc_link
*l_ptr
, struct sk_buff
*buf
);
236 int tipc_link_send_buf(struct tipc_link
*l_ptr
, struct sk_buff
*buf
);
237 u32
tipc_link_get_max_pkt(u32 dest
, u32 selector
);
238 int tipc_link_iovec_xmit_fast(struct tipc_port
*sender
,
239 struct iovec
const *msg_sect
,
240 unsigned int len
, u32 destnode
);
241 void tipc_link_bundle_rcv(struct sk_buff
*buf
);
242 int tipc_link_frag_rcv(struct sk_buff
**reasm_head
,
243 struct sk_buff
**reasm_tail
,
244 struct sk_buff
**fbuf
);
245 void tipc_link_proto_xmit(struct tipc_link
*l_ptr
, u32 msg_typ
, int prob
,
246 u32 gap
, u32 tolerance
, u32 priority
, u32 acked_mtu
);
247 void tipc_link_push_queue(struct tipc_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 tipc_link
*l_ptr
, int all
);
251 void tipc_link_set_queue_limits(struct tipc_link
*l_ptr
, u32 window
);
252 void tipc_link_retransmit(struct tipc_link
*l_ptr
,
253 struct sk_buff
*start
, u32 retransmits
);
256 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
258 static inline u32
buf_seqno(struct sk_buff
*buf
)
260 return msg_seqno(buf_msg(buf
));
263 static inline u32
mod(u32 x
)
268 static inline int between(u32 lower
, u32 upper
, u32 n
)
270 if ((lower
< n
) && (n
< upper
))
272 if ((upper
< lower
) && ((n
> lower
) || (n
< upper
)))
277 static inline int less_eq(u32 left
, u32 right
)
279 return mod(right
- left
) < 32768u;
282 static inline int less(u32 left
, u32 right
)
284 return less_eq(left
, right
) && (mod(right
) != mod(left
));
287 static inline u32
lesser(u32 left
, u32 right
)
289 return less_eq(left
, right
) ? left
: right
;
294 * Link status checking routines
296 static inline int link_working_working(struct tipc_link
*l_ptr
)
298 return l_ptr
->state
== WORKING_WORKING
;
301 static inline int link_working_unknown(struct tipc_link
*l_ptr
)
303 return l_ptr
->state
== WORKING_UNKNOWN
;
306 static inline int link_reset_unknown(struct tipc_link
*l_ptr
)
308 return l_ptr
->state
== RESET_UNKNOWN
;
311 static inline int link_reset_reset(struct tipc_link
*l_ptr
)
313 return l_ptr
->state
== RESET_RESET
;
316 static inline int link_congested(struct tipc_link
*l_ptr
)
318 return l_ptr
->out_queue_size
>= l_ptr
->queue_limit
[0];