xref: /openbmc/linux/net/tipc/link.h (revision 9b9c2cd4)
1 /*
2  * net/tipc/link.h: Include file for TIPC link code
3  *
4  * Copyright (c) 1995-2006, 2013-2014, Ericsson AB
5  * Copyright (c) 2004-2005, 2010-2011, 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 <net/genetlink.h>
41 #include "msg.h"
42 #include "node.h"
43 
44 /* TIPC-specific error codes
45 */
46 #define ELINKCONG EAGAIN	/* link congestion <=> resource unavailable */
47 
48 /* Out-of-range value for link sequence numbers
49  */
50 #define INVALID_LINK_SEQ 0x10000
51 
52 /* Link FSM events:
53  */
54 enum {
55 	LINK_ESTABLISH_EVT       = 0xec1ab1e,
56 	LINK_PEER_RESET_EVT      = 0x9eed0e,
57 	LINK_FAILURE_EVT         = 0xfa110e,
58 	LINK_RESET_EVT           = 0x10ca1d0e,
59 	LINK_FAILOVER_BEGIN_EVT  = 0xfa110bee,
60 	LINK_FAILOVER_END_EVT    = 0xfa110ede,
61 	LINK_SYNCH_BEGIN_EVT     = 0xc1ccbee,
62 	LINK_SYNCH_END_EVT       = 0xc1ccede
63 };
64 
65 /* Events returned from link at packet reception or at timeout
66  */
67 enum {
68 	TIPC_LINK_UP_EVT       = 1,
69 	TIPC_LINK_DOWN_EVT     = (1 << 1),
70 	TIPC_LINK_SND_BC_ACK   = (1 << 2)
71 };
72 
73 /* Starting value for maximum packet size negotiation on unicast links
74  * (unless bearer MTU is less)
75  */
76 #define MAX_PKT_DEFAULT 1500
77 
78 struct tipc_stats {
79 	u32 sent_info;		/* used in counting # sent packets */
80 	u32 recv_info;		/* used in counting # recv'd packets */
81 	u32 sent_states;
82 	u32 recv_states;
83 	u32 sent_probes;
84 	u32 recv_probes;
85 	u32 sent_nacks;
86 	u32 recv_nacks;
87 	u32 sent_acks;
88 	u32 sent_bundled;
89 	u32 sent_bundles;
90 	u32 recv_bundled;
91 	u32 recv_bundles;
92 	u32 retransmitted;
93 	u32 sent_fragmented;
94 	u32 sent_fragments;
95 	u32 recv_fragmented;
96 	u32 recv_fragments;
97 	u32 link_congs;		/* # port sends blocked by congestion */
98 	u32 deferred_recv;
99 	u32 duplicates;
100 	u32 max_queue_sz;	/* send queue size high water mark */
101 	u32 accu_queue_sz;	/* used for send queue size profiling */
102 	u32 queue_sz_counts;	/* used for send queue size profiling */
103 	u32 msg_length_counts;	/* used for message length profiling */
104 	u32 msg_lengths_total;	/* used for message length profiling */
105 	u32 msg_length_profile[7]; /* used for msg. length profiling */
106 };
107 
108 /**
109  * struct tipc_link - TIPC link data structure
110  * @addr: network address of link's peer node
111  * @name: link name character string
112  * @media_addr: media address to use when sending messages over link
113  * @timer: link timer
114  * @net: pointer to namespace struct
115  * @refcnt: reference counter for permanent references (owner node & timer)
116  * @peer_session: link session # being used by peer end of link
117  * @peer_bearer_id: bearer id used by link's peer endpoint
118  * @bearer_id: local bearer id used by link
119  * @tolerance: minimum link continuity loss needed to reset link [in ms]
120  * @keepalive_intv: link keepalive timer interval
121  * @abort_limit: # of unacknowledged continuity probes needed to reset link
122  * @state: current state of link FSM
123  * @peer_caps: bitmap describing capabilities of peer node
124  * @silent_intv_cnt: # of timer intervals without any reception from peer
125  * @proto_msg: template for control messages generated by link
126  * @pmsg: convenience pointer to "proto_msg" field
127  * @priority: current link priority
128  * @net_plane: current link network plane ('A' through 'H')
129  * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
130  * @exp_msg_count: # of tunnelled messages expected during link changeover
131  * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
132  * @mtu: current maximum packet size for this link
133  * @advertised_mtu: advertised own mtu when link is being established
134  * @transmitq: queue for sent, non-acked messages
135  * @backlogq: queue for messages waiting to be sent
136  * @snt_nxt: next sequence number to use for outbound messages
137  * @last_retransmitted: sequence number of most recently retransmitted message
138  * @stale_count: # of identical retransmit requests made by peer
139  * @ackers: # of peers that needs to ack each packet before it can be released
140  * @acked: # last packet acked by a certain peer. Used for broadcast.
141  * @rcv_nxt: next sequence number to expect for inbound messages
142  * @deferred_queue: deferred queue saved OOS b'cast message received from node
143  * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
144  * @inputq: buffer queue for messages to be delivered upwards
145  * @namedq: buffer queue for name table messages to be delivered upwards
146  * @next_out: ptr to first unsent outbound message in queue
147  * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
148  * @long_msg_seq_no: next identifier to use for outbound fragmented messages
149  * @reasm_buf: head of partially reassembled inbound message fragments
150  * @bc_rcvr: marks that this is a broadcast receiver link
151  * @stats: collects statistics regarding link activity
152  */
153 struct tipc_link {
154 	u32 addr;
155 	char name[TIPC_MAX_LINK_NAME];
156 	struct tipc_media_addr *media_addr;
157 	struct net *net;
158 
159 	/* Management and link supervision data */
160 	u32 peer_session;
161 	u32 peer_bearer_id;
162 	u32 bearer_id;
163 	u32 tolerance;
164 	unsigned long keepalive_intv;
165 	u32 abort_limit;
166 	u32 state;
167 	u16 peer_caps;
168 	bool active;
169 	u32 silent_intv_cnt;
170 	struct {
171 		unchar hdr[INT_H_SIZE];
172 		unchar body[TIPC_MAX_IF_NAME];
173 	} proto_msg;
174 	struct tipc_msg *pmsg;
175 	u32 priority;
176 	char net_plane;
177 
178 	/* Failover/synch */
179 	u16 drop_point;
180 	struct sk_buff *failover_reasm_skb;
181 
182 	/* Max packet negotiation */
183 	u16 mtu;
184 	u16 advertised_mtu;
185 
186 	/* Sending */
187 	struct sk_buff_head transmq;
188 	struct sk_buff_head backlogq;
189 	struct {
190 		u16 len;
191 		u16 limit;
192 	} backlog[5];
193 	u16 snd_nxt;
194 	u16 last_retransm;
195 	u16 window;
196 	u32 stale_count;
197 
198 	/* Reception */
199 	u16 rcv_nxt;
200 	u32 rcv_unacked;
201 	struct sk_buff_head deferdq;
202 	struct sk_buff_head *inputq;
203 	struct sk_buff_head *namedq;
204 
205 	/* Congestion handling */
206 	struct sk_buff_head wakeupq;
207 
208 	/* Fragmentation/reassembly */
209 	struct sk_buff *reasm_buf;
210 
211 	/* Broadcast */
212 	u16 ackers;
213 	u16 acked;
214 	struct tipc_link *bc_rcvlink;
215 	struct tipc_link *bc_sndlink;
216 	int nack_state;
217 	bool bc_peer_is_up;
218 
219 	/* Statistics */
220 	struct tipc_stats stats;
221 };
222 
223 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
224 		      int tolerance, char net_plane, u32 mtu, int priority,
225 		      int window, u32 session, u32 ownnode, u32 peer,
226 		      u16 peer_caps,
227 		      struct tipc_link *bc_sndlink,
228 		      struct tipc_link *bc_rcvlink,
229 		      struct sk_buff_head *inputq,
230 		      struct sk_buff_head *namedq,
231 		      struct tipc_link **link);
232 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
233 			 int mtu, int window, u16 peer_caps,
234 			 struct sk_buff_head *inputq,
235 			 struct sk_buff_head *namedq,
236 			 struct tipc_link *bc_sndlink,
237 			 struct tipc_link **link);
238 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
239 			   int mtyp, struct sk_buff_head *xmitq);
240 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
241 int tipc_link_fsm_evt(struct tipc_link *l, int evt);
242 void tipc_link_reset_fragments(struct tipc_link *l_ptr);
243 bool tipc_link_is_up(struct tipc_link *l);
244 bool tipc_link_peer_is_down(struct tipc_link *l);
245 bool tipc_link_is_reset(struct tipc_link *l);
246 bool tipc_link_is_establishing(struct tipc_link *l);
247 bool tipc_link_is_synching(struct tipc_link *l);
248 bool tipc_link_is_failingover(struct tipc_link *l);
249 bool tipc_link_is_blocked(struct tipc_link *l);
250 void tipc_link_set_active(struct tipc_link *l, bool active);
251 void tipc_link_reset(struct tipc_link *l_ptr);
252 int tipc_link_xmit(struct tipc_link *link,	struct sk_buff_head *list,
253 		   struct sk_buff_head *xmitq);
254 void tipc_link_set_queue_limits(struct tipc_link *l, u32 window);
255 
256 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb);
257 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info);
258 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info);
259 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info);
260 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[]);
261 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq);
262 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
263 		  struct sk_buff_head *xmitq);
264 int tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
265 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
266 			   struct tipc_link *uc_l,
267 			   struct sk_buff_head *xmitq);
268 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
269 			      struct tipc_link *rcv_l,
270 			      struct sk_buff_head *xmitq);
271 int tipc_link_bc_peers(struct tipc_link *l);
272 void tipc_link_set_mtu(struct tipc_link *l, int mtu);
273 int tipc_link_mtu(struct tipc_link *l);
274 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
275 			  struct sk_buff_head *xmitq);
276 void tipc_link_build_bc_sync_msg(struct tipc_link *l,
277 				 struct sk_buff_head *xmitq);
278 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr);
279 void tipc_link_bc_sync_rcv(struct tipc_link *l,   struct tipc_msg *hdr,
280 			   struct sk_buff_head *xmitq);
281 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
282 			  struct sk_buff_head *xmitq);
283 #endif
284