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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2  * net/tipc/link.h: Include file for TIPC link code
  3  *
  4  * Copyright (c) 1995-2006, Ericsson AB
  5  * Copyright (c) 2004-2005, 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 "dbg.h"
 41 #include "msg.h"
 42 #include "bearer.h"
 43 #include "node.h"
 44 
 45 #define PUSH_FAILED   1
 46 #define PUSH_FINISHED 2
 47 
 48 /*
 49  * Link states
 50  */
 51 
 52 #define WORKING_WORKING 560810u
 53 #define WORKING_UNKNOWN 560811u
 54 #define RESET_UNKNOWN   560812u
 55 #define RESET_RESET     560813u
 56 
 57 /*
 58  * Starting value for maximum packet size negotiation on unicast links
 59  * (unless bearer MTU is less)
 60  */
 61 
 62 #define MAX_PKT_DEFAULT 1500
 63 
 64 /**
 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
 69  * @timer: link timer
 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
112  */
113 
114 struct link {
115         u32 addr;
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;
121 
122         /* Management and link supervision data */
123         int started;
124         u32 checkpoint;
125         u32 peer_session;
126         u32 peer_bearer_id;
127         struct bearer *b_ptr;
128         u32 tolerance;
129         u32 continuity_interval;
130         u32 abort_limit;
131         int state;
132         int blocked;
133         u32 fsm_msg_cnt;
134         struct {
135                 unchar hdr[INT_H_SIZE];
136                 unchar body[TIPC_MAX_IF_NAME];
137         } proto_msg;
138         struct tipc_msg *pmsg;
139         u32 priority;
140         u32 queue_limit[15];    /* queue_limit[0]==window limit */
141 
142         /* Changeover */
143         u32 exp_msg_count;
144         u32 reset_checkpoint;
145 
146         /* Max packet negotiation */
147         u32 max_pkt;
148         u32 max_pkt_target;
149         u32 max_pkt_probes;
150 
151         /* Sending */
152         u32 out_queue_size;
153         struct sk_buff *first_out;
154         struct sk_buff *last_out;
155         u32 next_out_no;
156         u32 last_retransmitted;
157         u32 stale_count;
158 
159         /* Reception */
160         u32 next_in_no;
161         u32 deferred_inqueue_sz;
162         struct sk_buff *oldest_deferred_in;
163         struct sk_buff *newest_deferred_in;
164         u32 unacked_window;
165 
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;
172 
173         /* Fragmentation/defragmentation */
174         u32 long_msg_seq_no;
175         struct sk_buff *defragm_buf;
176 
177         /* Statistics */
178         struct {
179                 u32 sent_info;          /* used in counting # sent packets */
180                 u32 recv_info;          /* used in counting # recv'd packets */
181                 u32 sent_states;
182                 u32 recv_states;
183                 u32 sent_probes;
184                 u32 recv_probes;
185                 u32 sent_nacks;
186                 u32 recv_nacks;
187                 u32 sent_acks;
188                 u32 sent_bundled;
189                 u32 sent_bundles;
190                 u32 recv_bundled;
191                 u32 recv_bundles;
192                 u32 retransmitted;
193                 u32 sent_fragmented;
194                 u32 sent_fragments;
195                 u32 recv_fragmented;
196                 u32 recv_fragments;
197                 u32 link_congs;         /* # port sends blocked by congestion */
198                 u32 bearer_congs;
199                 u32 deferred_recv;
200                 u32 duplicates;
201 
202                 /* for statistical profiling of send queue size */
203 
204                 u32 max_queue_sz;
205                 u32 accu_queue_sz;
206                 u32 queue_sz_counts;
207 
208                 /* for statistical profiling of message lengths */
209 
210                 u32 msg_length_counts;
211                 u32 msg_lengths_total;
212                 u32 msg_length_profile[7];
213 #if 0
214                 u32 sent_tunneled;
215                 u32 recv_tunneled;
216 #endif
217         } stats;
218 
219         struct print_buf print_buf;
220 };
221 
222 struct port;
223 
224 struct link *tipc_link_create(struct bearer *b_ptr, const u32 peer,
225                               const struct tipc_media_addr *media_addr);
226 void tipc_link_delete(struct link *l_ptr);
227 void tipc_link_changeover(struct link *l_ptr);
228 void tipc_link_send_duplicate(struct link *l_ptr, struct link *dest);
229 void tipc_link_reset_fragments(struct link *l_ptr);
230 int tipc_link_is_up(struct link *l_ptr);
231 int tipc_link_is_active(struct link *l_ptr);
232 void tipc_link_start(struct link *l_ptr);
233 u32 tipc_link_push_packet(struct link *l_ptr);
234 void tipc_link_stop(struct link *l_ptr);
235 struct sk_buff *tipc_link_cmd_config(const void *req_tlv_area, int req_tlv_space, u16 cmd);
236 struct sk_buff *tipc_link_cmd_show_stats(const void *req_tlv_area, int req_tlv_space);
237 struct sk_buff *tipc_link_cmd_reset_stats(const void *req_tlv_area, int req_tlv_space);
238 void tipc_link_reset(struct link *l_ptr);
239 int tipc_link_send(struct sk_buff *buf, u32 dest, u32 selector);
240 int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf);
241 u32 tipc_link_get_max_pkt(u32 dest,u32 selector);
242 int tipc_link_send_sections_fast(struct port* sender,
243                                  struct iovec const *msg_sect,
244                                  const u32 num_sect,
245                                  u32 destnode);
246 int tipc_link_send_long_buf(struct link *l_ptr, struct sk_buff *buf);
247 void tipc_link_tunnel(struct link *l_ptr, struct tipc_msg *tnl_hdr,
248                       struct tipc_msg *msg, u32 selector);
249 void tipc_link_recv_bundle(struct sk_buff *buf);
250 int  tipc_link_recv_fragment(struct sk_buff **pending,
251                              struct sk_buff **fb,
252                              struct tipc_msg **msg);
253 void tipc_link_send_proto_msg(struct link *l_ptr, u32 msg_typ, int prob, u32 gap,
254                               u32 tolerance, u32 priority, u32 acked_mtu);
255 void tipc_link_push_queue(struct link *l_ptr);
256 u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
257                    struct sk_buff *buf);
258 void tipc_link_wakeup_ports(struct link *l_ptr, int all);
259 void tipc_link_set_queue_limits(struct link *l_ptr, u32 window);
260 void tipc_link_retransmit(struct link *l_ptr, struct sk_buff *start, u32 retransmits);
261 
262 /*
263  * Link sequence number manipulation routines (uses modulo 2**16 arithmetic)
264  */
265 
266 static inline u32 mod(u32 x)
267 {
268         return x & 0xffffu;
269 }
270 
271 static inline int between(u32 lower, u32 upper, u32 n)
272 {
273         if ((lower < n) && (n < upper))
274                 return 1;
275         if ((upper < lower) && ((n > lower) || (n < upper)))
276                 return 1;
277         return 0;
278 }
279 
280 static inline int less_eq(u32 left, u32 right)
281 {
282         return (mod(right - left) < 32768u);
283 }
284 
285 static inline int less(u32 left, u32 right)
286 {
287         return (less_eq(left, right) && (mod(right) != mod(left)));
288 }
289 
290 static inline u32 lesser(u32 left, u32 right)
291 {
292         return less_eq(left, right) ? left : right;
293 }
294 
295 #endif
296 
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