2 * net/tipc/link.h: Include file for TIPC link code
4 * Copyright (c) 1995-2006, 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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45 #define PUSH_FINISHED 2
48 * Out-of-range value for link sequence numbers
50 #define INVALID_LINK_SEQ 0x10000
55 #define WORKING_WORKING 560810u
56 #define WORKING_UNKNOWN 560811u
57 #define RESET_UNKNOWN 560812u
58 #define RESET_RESET 560813u
61 * Starting value for maximum packet size negotiation on unicast links
62 * (unless bearer MTU is less)
64 #define MAX_PKT_DEFAULT 1500
67 * struct tipc_link - TIPC link data structure
68 * @addr: network address of link's peer node
69 * @name: link name character string
70 * @media_addr: media address to use when sending messages over link
72 * @owner: pointer to peer node
73 * @link_list: adjacent links in bearer's list of links
74 * @started: indicates if link has been started
75 * @checkpoint: reference point for triggering link continuity checking
76 * @peer_session: link session # being used by peer end of link
77 * @peer_bearer_id: bearer id used by link's peer endpoint
78 * @b_ptr: pointer to bearer used by link
79 * @tolerance: minimum link continuity loss needed to reset link [in ms]
80 * @continuity_interval: link continuity testing interval [in ms]
81 * @abort_limit: # of unacknowledged continuity probes needed to reset link
82 * @state: current state of link FSM
83 * @blocked: indicates if link has been administratively blocked
84 * @fsm_msg_cnt: # of protocol messages link FSM has sent in current state
85 * @proto_msg: template for control messages generated by link
86 * @pmsg: convenience pointer to "proto_msg" field
87 * @priority: current link priority
88 * @queue_limit: outbound message queue congestion thresholds (indexed by user)
89 * @exp_msg_count: # of tunnelled messages expected during link changeover
90 * @reset_checkpoint: seq # of last acknowledged message at time of link reset
91 * @max_pkt: current maximum packet size for this link
92 * @max_pkt_target: desired maximum packet size for this link
93 * @max_pkt_probes: # of probes based on current (max_pkt, max_pkt_target)
94 * @out_queue_size: # of messages in outbound message queue
95 * @first_out: ptr to first outbound message in queue
96 * @last_out: ptr to last outbound message in queue
97 * @next_out_no: next sequence number to use for outbound messages
98 * @last_retransmitted: sequence number of most recently retransmitted message
99 * @stale_count: # of identical retransmit requests made by peer
100 * @next_in_no: next sequence number to expect for inbound messages
101 * @deferred_inqueue_sz: # of messages in inbound message queue
102 * @oldest_deferred_in: ptr to first inbound message in queue
103 * @newest_deferred_in: ptr to last inbound message in queue
104 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
105 * @proto_msg_queue: ptr to (single) outbound control message
106 * @retransm_queue_size: number of messages to retransmit
107 * @retransm_queue_head: sequence number of first message to retransmit
108 * @next_out: ptr to first unsent outbound message in queue
109 * @waiting_ports: linked list of ports waiting for link congestion to abate
110 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
111 * @defragm_buf: list of partially reassembled inbound message fragments
112 * @stats: collects statistics regarding 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 tipc_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 */
201 u32 max_queue_sz
; /* send queue size high water mark */
202 u32 accu_queue_sz
; /* used for send queue size profiling */
203 u32 queue_sz_counts
; /* used for send queue size profiling */
204 u32 msg_length_counts
; /* used for message length profiling */
205 u32 msg_lengths_total
; /* used for message length profiling */
206 u32 msg_length_profile
[7]; /* used for msg. length profiling */
212 struct tipc_link
*tipc_link_create(struct tipc_node
*n_ptr
,
213 struct tipc_bearer
*b_ptr
,
214 const struct tipc_media_addr
*media_addr
);
215 void tipc_link_delete(struct tipc_link
*l_ptr
);
216 void tipc_link_changeover(struct tipc_link
*l_ptr
);
217 void tipc_link_send_duplicate(struct tipc_link
*l_ptr
, struct tipc_link
*dest
);
218 void tipc_link_reset_fragments(struct tipc_link
*l_ptr
);
219 int tipc_link_is_up(struct tipc_link
*l_ptr
);
220 int tipc_link_is_active(struct tipc_link
*l_ptr
);
221 u32
tipc_link_push_packet(struct tipc_link
*l_ptr
);
222 void tipc_link_stop(struct tipc_link
*l_ptr
);
223 struct sk_buff
*tipc_link_cmd_config(const void *req_tlv_area
, int req_tlv_space
, u16 cmd
);
224 struct sk_buff
*tipc_link_cmd_show_stats(const void *req_tlv_area
, int req_tlv_space
);
225 struct sk_buff
*tipc_link_cmd_reset_stats(const void *req_tlv_area
, int req_tlv_space
);
226 void tipc_link_reset(struct tipc_link
*l_ptr
);
227 int tipc_link_send(struct sk_buff
*buf
, u32 dest
, u32 selector
);
228 void tipc_link_send_names(struct list_head
*message_list
, u32 dest
);
229 int tipc_link_send_buf(struct tipc_link
*l_ptr
, struct sk_buff
*buf
);
230 u32
tipc_link_get_max_pkt(u32 dest
, u32 selector
);
231 int tipc_link_send_sections_fast(struct tipc_port
*sender
,
232 struct iovec
const *msg_sect
,
234 unsigned int total_len
,
236 void tipc_link_recv_bundle(struct sk_buff
*buf
);
237 int tipc_link_recv_fragment(struct sk_buff
**pending
,
239 struct tipc_msg
**msg
);
240 void tipc_link_send_proto_msg(struct tipc_link
*l_ptr
, u32 msg_typ
, int prob
,
241 u32 gap
, u32 tolerance
, u32 priority
,
243 void tipc_link_push_queue(struct tipc_link
*l_ptr
);
244 u32
tipc_link_defer_pkt(struct sk_buff
**head
, struct sk_buff
**tail
,
245 struct sk_buff
*buf
);
246 void tipc_link_wakeup_ports(struct tipc_link
*l_ptr
, int all
);
247 void tipc_link_set_queue_limits(struct tipc_link
*l_ptr
, u32 window
);
248 void tipc_link_retransmit(struct tipc_link
*l_ptr
,
249 struct sk_buff
*start
, u32 retransmits
);
252 * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
254 static inline u32
buf_seqno(struct sk_buff
*buf
)
256 return msg_seqno(buf_msg(buf
));
259 static inline u32
mod(u32 x
)
264 static inline int between(u32 lower
, u32 upper
, u32 n
)
266 if ((lower
< n
) && (n
< upper
))
268 if ((upper
< lower
) && ((n
> lower
) || (n
< upper
)))
273 static inline int less_eq(u32 left
, u32 right
)
275 return mod(right
- left
) < 32768u;
278 static inline int less(u32 left
, u32 right
)
280 return less_eq(left
, right
) && (mod(right
) != mod(left
));
283 static inline u32
lesser(u32 left
, u32 right
)
285 return less_eq(left
, right
) ? left
: right
;
290 * Link status checking routines
292 static inline int link_working_working(struct tipc_link
*l_ptr
)
294 return l_ptr
->state
== WORKING_WORKING
;
297 static inline int link_working_unknown(struct tipc_link
*l_ptr
)
299 return l_ptr
->state
== WORKING_UNKNOWN
;
302 static inline int link_reset_unknown(struct tipc_link
*l_ptr
)
304 return l_ptr
->state
== RESET_UNKNOWN
;
307 static inline int link_reset_reset(struct tipc_link
*l_ptr
)
309 return l_ptr
->state
== RESET_RESET
;
312 static inline int link_blocked(struct tipc_link
*l_ptr
)
314 return l_ptr
->exp_msg_count
|| l_ptr
->blocked
;
317 static inline int link_congested(struct tipc_link
*l_ptr
)
319 return l_ptr
->out_queue_size
>= l_ptr
->queue_limit
[0];