xref: /openbmc/linux/net/tipc/core.h (revision 93dc544c)
1 /*
2  * net/tipc/core.h: Include file for TIPC global declarations
3  *
4  * Copyright (c) 2005-2006, Ericsson AB
5  * Copyright (c) 2005-2007, 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_CORE_H
38 #define _TIPC_CORE_H
39 
40 #include <linux/tipc.h>
41 #include <linux/tipc_config.h>
42 #include <net/tipc/tipc_msg.h>
43 #include <net/tipc/tipc_port.h>
44 #include <net/tipc/tipc_bearer.h>
45 #include <net/tipc/tipc.h>
46 #include <linux/types.h>
47 #include <linux/kernel.h>
48 #include <linux/errno.h>
49 #include <linux/mm.h>
50 #include <linux/timer.h>
51 #include <linux/string.h>
52 #include <asm/uaccess.h>
53 #include <linux/interrupt.h>
54 #include <asm/atomic.h>
55 #include <asm/hardirq.h>
56 #include <linux/netdevice.h>
57 #include <linux/in.h>
58 #include <linux/list.h>
59 #include <linux/vmalloc.h>
60 
61 /*
62  * TIPC sanity test macros
63  */
64 
65 #define assert(i)  BUG_ON(!(i))
66 
67 /*
68  * TIPC system monitoring code
69  */
70 
71 /*
72  * TIPC's print buffer subsystem supports the following print buffers:
73  *
74  * TIPC_NULL : null buffer (i.e. print nowhere)
75  * TIPC_CONS : system console
76  * TIPC_LOG  : TIPC log buffer
77  * &buf	     : user-defined buffer (struct print_buf *)
78  *
79  * Note: TIPC_LOG is configured to echo its output to the system console;
80  *       user-defined buffers can be configured to do the same thing.
81  */
82 
83 extern struct print_buf *const TIPC_NULL;
84 extern struct print_buf *const TIPC_CONS;
85 extern struct print_buf *const TIPC_LOG;
86 
87 void tipc_printf(struct print_buf *, const char *fmt, ...);
88 
89 /*
90  * TIPC_OUTPUT is the destination print buffer for system messages.
91  */
92 
93 #ifndef TIPC_OUTPUT
94 #define TIPC_OUTPUT TIPC_LOG
95 #endif
96 
97 /*
98  * TIPC can be configured to send system messages to TIPC_OUTPUT
99  * or to the system console only.
100  */
101 
102 #ifdef CONFIG_TIPC_DEBUG
103 
104 #define err(fmt, arg...)  tipc_printf(TIPC_OUTPUT, \
105 					KERN_ERR "TIPC: " fmt, ## arg)
106 #define warn(fmt, arg...) tipc_printf(TIPC_OUTPUT, \
107 					KERN_WARNING "TIPC: " fmt, ## arg)
108 #define info(fmt, arg...) tipc_printf(TIPC_OUTPUT, \
109 					KERN_NOTICE "TIPC: " fmt, ## arg)
110 
111 #else
112 
113 #define err(fmt, arg...)  printk(KERN_ERR "TIPC: " fmt , ## arg)
114 #define info(fmt, arg...) printk(KERN_INFO "TIPC: " fmt , ## arg)
115 #define warn(fmt, arg...) printk(KERN_WARNING "TIPC: " fmt , ## arg)
116 
117 #endif
118 
119 /*
120  * DBG_OUTPUT is the destination print buffer for debug messages.
121  * It defaults to the the null print buffer, but can be redefined
122  * (typically in the individual .c files being debugged) to allow
123  * selected debug messages to be generated where needed.
124  */
125 
126 #ifndef DBG_OUTPUT
127 #define DBG_OUTPUT TIPC_NULL
128 #endif
129 
130 /*
131  * TIPC can be configured to send debug messages to the specified print buffer
132  * (typically DBG_OUTPUT) or to suppress them entirely.
133  */
134 
135 #ifdef CONFIG_TIPC_DEBUG
136 
137 #define dbg(fmt, arg...)  \
138 	do { \
139 		if (DBG_OUTPUT != TIPC_NULL) \
140 			tipc_printf(DBG_OUTPUT, fmt, ## arg); \
141 	} while (0)
142 #define msg_dbg(msg, txt) \
143 	do { \
144 		if (DBG_OUTPUT != TIPC_NULL) \
145 			tipc_msg_dbg(DBG_OUTPUT, msg, txt); \
146 	} while (0)
147 #define dump(fmt, arg...) \
148 	do { \
149 		if (DBG_OUTPUT != TIPC_NULL) \
150 			tipc_dump_dbg(DBG_OUTPUT, fmt, ##arg); \
151 	} while (0)
152 
153 void tipc_msg_dbg(struct print_buf *, struct tipc_msg *, const char *);
154 void tipc_dump_dbg(struct print_buf *, const char *fmt, ...);
155 
156 #else
157 
158 #define dbg(fmt, arg...)	do {} while (0)
159 #define msg_dbg(msg, txt)	do {} while (0)
160 #define dump(fmt, arg...)	do {} while (0)
161 
162 #define tipc_msg_dbg(...)	do {} while (0)
163 #define tipc_dump_dbg(...)	do {} while (0)
164 
165 #endif
166 
167 
168 /*
169  * TIPC-specific error codes
170  */
171 
172 #define ELINKCONG EAGAIN	/* link congestion <=> resource unavailable */
173 
174 /*
175  * Global configuration variables
176  */
177 
178 extern u32 tipc_own_addr;
179 extern int tipc_max_zones;
180 extern int tipc_max_clusters;
181 extern int tipc_max_nodes;
182 extern int tipc_max_slaves;
183 extern int tipc_max_ports;
184 extern int tipc_max_subscriptions;
185 extern int tipc_max_publications;
186 extern int tipc_net_id;
187 extern int tipc_remote_management;
188 
189 /*
190  * Other global variables
191  */
192 
193 extern int tipc_mode;
194 extern int tipc_random;
195 extern const char tipc_alphabet[];
196 extern atomic_t tipc_user_count;
197 
198 
199 /*
200  * Routines available to privileged subsystems
201  */
202 
203 extern int  tipc_core_start(void);
204 extern void tipc_core_stop(void);
205 extern int  tipc_core_start_net(unsigned long addr);
206 extern void tipc_core_stop_net(void);
207 extern int  tipc_handler_start(void);
208 extern void tipc_handler_stop(void);
209 extern int  tipc_netlink_start(void);
210 extern void tipc_netlink_stop(void);
211 extern int  tipc_socket_init(void);
212 extern void tipc_socket_stop(void);
213 
214 static inline int delimit(int val, int min, int max)
215 {
216 	if (val > max)
217 		return max;
218 	if (val < min)
219 		return min;
220 	return val;
221 }
222 
223 
224 /*
225  * TIPC timer and signal code
226  */
227 
228 typedef void (*Handler) (unsigned long);
229 
230 u32 tipc_k_signal(Handler routine, unsigned long argument);
231 
232 /**
233  * k_init_timer - initialize a timer
234  * @timer: pointer to timer structure
235  * @routine: pointer to routine to invoke when timer expires
236  * @argument: value to pass to routine when timer expires
237  *
238  * Timer must be initialized before use (and terminated when no longer needed).
239  */
240 
241 static inline void k_init_timer(struct timer_list *timer, Handler routine,
242 				unsigned long argument)
243 {
244 	dbg("initializing timer %p\n", timer);
245 	setup_timer(timer, routine, argument);
246 }
247 
248 /**
249  * k_start_timer - start a timer
250  * @timer: pointer to timer structure
251  * @msec: time to delay (in ms)
252  *
253  * Schedules a previously initialized timer for later execution.
254  * If timer is already running, the new timeout overrides the previous request.
255  *
256  * To ensure the timer doesn't expire before the specified delay elapses,
257  * the amount of delay is rounded up when converting to the jiffies
258  * then an additional jiffy is added to account for the fact that
259  * the starting time may be in the middle of the current jiffy.
260  */
261 
262 static inline void k_start_timer(struct timer_list *timer, unsigned long msec)
263 {
264 	dbg("starting timer %p for %u\n", timer, msec);
265 	mod_timer(timer, jiffies + msecs_to_jiffies(msec) + 1);
266 }
267 
268 /**
269  * k_cancel_timer - cancel a timer
270  * @timer: pointer to timer structure
271  *
272  * Cancels a previously initialized timer.
273  * Can be called safely even if the timer is already inactive.
274  *
275  * WARNING: Must not be called when holding locks required by the timer's
276  *          timeout routine, otherwise deadlock can occur on SMP systems!
277  */
278 
279 static inline void k_cancel_timer(struct timer_list *timer)
280 {
281 	dbg("cancelling timer %p\n", timer);
282 	del_timer_sync(timer);
283 }
284 
285 /**
286  * k_term_timer - terminate a timer
287  * @timer: pointer to timer structure
288  *
289  * Prevents further use of a previously initialized timer.
290  *
291  * WARNING: Caller must ensure timer isn't currently running.
292  *
293  * (Do not "enhance" this routine to automatically cancel an active timer,
294  * otherwise deadlock can arise when a timeout routine calls k_term_timer.)
295  */
296 
297 static inline void k_term_timer(struct timer_list *timer)
298 {
299 	dbg("terminating timer %p\n", timer);
300 }
301 
302 
303 /*
304  * TIPC message buffer code
305  *
306  * TIPC message buffer headroom reserves space for the worst-case
307  * link-level device header (in case the message is sent off-node).
308  *
309  * Note: Headroom should be a multiple of 4 to ensure the TIPC header fields
310  *       are word aligned for quicker access
311  */
312 
313 #define BUF_HEADROOM LL_MAX_HEADER
314 
315 struct tipc_skb_cb {
316 	void *handle;
317 };
318 
319 #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
320 
321 
322 static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
323 {
324 	return (struct tipc_msg *)skb->data;
325 }
326 
327 /**
328  * buf_acquire - creates a TIPC message buffer
329  * @size: message size (including TIPC header)
330  *
331  * Returns a new buffer with data pointers set to the specified size.
332  *
333  * NOTE: Headroom is reserved to allow prepending of a data link header.
334  *       There may also be unrequested tailroom present at the buffer's end.
335  */
336 
337 static inline struct sk_buff *buf_acquire(u32 size)
338 {
339 	struct sk_buff *skb;
340 	unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
341 
342 	skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
343 	if (skb) {
344 		skb_reserve(skb, BUF_HEADROOM);
345 		skb_put(skb, size);
346 		skb->next = NULL;
347 	}
348 	return skb;
349 }
350 
351 /**
352  * buf_discard - frees a TIPC message buffer
353  * @skb: message buffer
354  *
355  * Frees a message buffer.  If passed NULL, just returns.
356  */
357 
358 static inline void buf_discard(struct sk_buff *skb)
359 {
360 	kfree_skb(skb);
361 }
362 
363 /**
364  * buf_linearize - convert a TIPC message buffer into a single contiguous piece
365  * @skb: message buffer
366  *
367  * Returns 0 on success.
368  */
369 
370 static inline int buf_linearize(struct sk_buff *skb)
371 {
372 	return skb_linearize(skb);
373 }
374 
375 #endif
376