xref: /openbmc/linux/net/tipc/core.h (revision f42b3800)
1 /*
2  * net/tipc/core.h: Include file for TIPC global declarations
3  *
4  * Copyright (c) 2005-2006, Ericsson AB
5  * Copyright (c) 2005-2006, 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 debugging code
63  */
64 
65 #define assert(i)  BUG_ON(!(i))
66 
67 struct tipc_msg;
68 extern struct print_buf *TIPC_NULL, *TIPC_CONS, *TIPC_LOG;
69 extern struct print_buf *TIPC_TEE(struct print_buf *, struct print_buf *);
70 void tipc_msg_print(struct print_buf*,struct tipc_msg *,const char*);
71 void tipc_printf(struct print_buf *, const char *fmt, ...);
72 void tipc_dump(struct print_buf*,const char *fmt, ...);
73 
74 #ifdef CONFIG_TIPC_DEBUG
75 
76 /*
77  * TIPC debug support included:
78  * - system messages are printed to TIPC_OUTPUT print buffer
79  * - debug messages are printed to DBG_OUTPUT print buffer
80  */
81 
82 #define err(fmt, arg...)  tipc_printf(TIPC_OUTPUT, KERN_ERR "TIPC: " fmt, ## arg)
83 #define warn(fmt, arg...) tipc_printf(TIPC_OUTPUT, KERN_WARNING "TIPC: " fmt, ## arg)
84 #define info(fmt, arg...) tipc_printf(TIPC_OUTPUT, KERN_NOTICE "TIPC: " fmt, ## arg)
85 
86 #define dbg(fmt, arg...)  do {if (DBG_OUTPUT != TIPC_NULL) tipc_printf(DBG_OUTPUT, fmt, ## arg);} while(0)
87 #define msg_dbg(msg, txt) do {if (DBG_OUTPUT != TIPC_NULL) tipc_msg_print(DBG_OUTPUT, msg, txt);} while(0)
88 #define dump(fmt, arg...) do {if (DBG_OUTPUT != TIPC_NULL) tipc_dump(DBG_OUTPUT, fmt, ##arg);} while(0)
89 
90 
91 /*
92  * By default, TIPC_OUTPUT is defined to be system console and TIPC log buffer,
93  * while DBG_OUTPUT is the null print buffer.  These defaults can be changed
94  * here, or on a per .c file basis, by redefining these symbols.  The following
95  * print buffer options are available:
96  *
97  * TIPC_NULL		   : null buffer (i.e. print nowhere)
98  * TIPC_CONS		   : system console
99  * TIPC_LOG		   : TIPC log buffer
100  * &buf			   : user-defined buffer (struct print_buf *)
101  * TIPC_TEE(&buf_a,&buf_b) : list of buffers (eg. TIPC_TEE(TIPC_CONS,TIPC_LOG))
102  */
103 
104 #ifndef TIPC_OUTPUT
105 #define TIPC_OUTPUT TIPC_TEE(TIPC_CONS,TIPC_LOG)
106 #endif
107 
108 #ifndef DBG_OUTPUT
109 #define DBG_OUTPUT TIPC_NULL
110 #endif
111 
112 #else
113 
114 /*
115  * TIPC debug support not included:
116  * - system messages are printed to system console
117  * - debug messages are not printed
118  */
119 
120 #define err(fmt, arg...)  printk(KERN_ERR "TIPC: " fmt , ## arg)
121 #define info(fmt, arg...) printk(KERN_INFO "TIPC: " fmt , ## arg)
122 #define warn(fmt, arg...) printk(KERN_WARNING "TIPC: " fmt , ## arg)
123 
124 #define dbg(fmt, arg...) do {} while (0)
125 #define msg_dbg(msg,txt) do {} while (0)
126 #define dump(fmt,arg...) do {} while (0)
127 
128 
129 /*
130  * TIPC_OUTPUT is defined to be the system console, while DBG_OUTPUT is
131  * the null print buffer.  Thes ensures that any system or debug messages
132  * that are generated without using the above macros are handled correctly.
133  */
134 
135 #undef  TIPC_OUTPUT
136 #define TIPC_OUTPUT TIPC_CONS
137 
138 #undef  DBG_OUTPUT
139 #define DBG_OUTPUT TIPC_NULL
140 
141 #endif
142 
143 
144 /*
145  * TIPC-specific error codes
146  */
147 
148 #define ELINKCONG EAGAIN	/* link congestion <=> resource unavailable */
149 
150 /*
151  * Global configuration variables
152  */
153 
154 extern u32 tipc_own_addr;
155 extern int tipc_max_zones;
156 extern int tipc_max_clusters;
157 extern int tipc_max_nodes;
158 extern int tipc_max_slaves;
159 extern int tipc_max_ports;
160 extern int tipc_max_subscriptions;
161 extern int tipc_max_publications;
162 extern int tipc_net_id;
163 extern int tipc_remote_management;
164 
165 /*
166  * Other global variables
167  */
168 
169 extern int tipc_mode;
170 extern int tipc_random;
171 extern const char tipc_alphabet[];
172 extern atomic_t tipc_user_count;
173 
174 
175 /*
176  * Routines available to privileged subsystems
177  */
178 
179 extern int  tipc_core_start(void);
180 extern void tipc_core_stop(void);
181 extern int  tipc_core_start_net(void);
182 extern void tipc_core_stop_net(void);
183 extern int  tipc_handler_start(void);
184 extern void tipc_handler_stop(void);
185 extern int  tipc_netlink_start(void);
186 extern void tipc_netlink_stop(void);
187 extern int  tipc_socket_init(void);
188 extern void tipc_socket_stop(void);
189 
190 static inline int delimit(int val, int min, int max)
191 {
192 	if (val > max)
193 		return max;
194 	if (val < min)
195 		return min;
196 	return val;
197 }
198 
199 
200 /*
201  * TIPC timer and signal code
202  */
203 
204 typedef void (*Handler) (unsigned long);
205 
206 u32 tipc_k_signal(Handler routine, unsigned long argument);
207 
208 /**
209  * k_init_timer - initialize a timer
210  * @timer: pointer to timer structure
211  * @routine: pointer to routine to invoke when timer expires
212  * @argument: value to pass to routine when timer expires
213  *
214  * Timer must be initialized before use (and terminated when no longer needed).
215  */
216 
217 static inline void k_init_timer(struct timer_list *timer, Handler routine,
218 				unsigned long argument)
219 {
220 	dbg("initializing timer %p\n", timer);
221 	setup_timer(timer, routine, argument);
222 }
223 
224 /**
225  * k_start_timer - start a timer
226  * @timer: pointer to timer structure
227  * @msec: time to delay (in ms)
228  *
229  * Schedules a previously initialized timer for later execution.
230  * If timer is already running, the new timeout overrides the previous request.
231  *
232  * To ensure the timer doesn't expire before the specified delay elapses,
233  * the amount of delay is rounded up when converting to the jiffies
234  * then an additional jiffy is added to account for the fact that
235  * the starting time may be in the middle of the current jiffy.
236  */
237 
238 static inline void k_start_timer(struct timer_list *timer, unsigned long msec)
239 {
240 	dbg("starting timer %p for %u\n", timer, msec);
241 	mod_timer(timer, jiffies + msecs_to_jiffies(msec) + 1);
242 }
243 
244 /**
245  * k_cancel_timer - cancel a timer
246  * @timer: pointer to timer structure
247  *
248  * Cancels a previously initialized timer.
249  * Can be called safely even if the timer is already inactive.
250  *
251  * WARNING: Must not be called when holding locks required by the timer's
252  *          timeout routine, otherwise deadlock can occur on SMP systems!
253  */
254 
255 static inline void k_cancel_timer(struct timer_list *timer)
256 {
257 	dbg("cancelling timer %p\n", timer);
258 	del_timer_sync(timer);
259 }
260 
261 /**
262  * k_term_timer - terminate a timer
263  * @timer: pointer to timer structure
264  *
265  * Prevents further use of a previously initialized timer.
266  *
267  * WARNING: Caller must ensure timer isn't currently running.
268  *
269  * (Do not "enhance" this routine to automatically cancel an active timer,
270  * otherwise deadlock can arise when a timeout routine calls k_term_timer.)
271  */
272 
273 static inline void k_term_timer(struct timer_list *timer)
274 {
275 	dbg("terminating timer %p\n", timer);
276 }
277 
278 
279 /*
280  * TIPC message buffer code
281  *
282  * TIPC message buffer headroom reserves space for a link-level header
283  * (in case the message is sent off-node),
284  * while ensuring TIPC header is word aligned for quicker access
285  *
286  * The largest header currently supported is 18 bytes, which is used when
287  * the standard 14 byte Ethernet header has 4 added bytes for VLAN info
288  */
289 
290 #define BUF_HEADROOM 20u
291 
292 struct tipc_skb_cb {
293 	void *handle;
294 };
295 
296 #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
297 
298 
299 static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
300 {
301 	return (struct tipc_msg *)skb->data;
302 }
303 
304 /**
305  * buf_acquire - creates a TIPC message buffer
306  * @size: message size (including TIPC header)
307  *
308  * Returns a new buffer with data pointers set to the specified size.
309  *
310  * NOTE: Headroom is reserved to allow prepending of a data link header.
311  *       There may also be unrequested tailroom present at the buffer's end.
312  */
313 
314 static inline struct sk_buff *buf_acquire(u32 size)
315 {
316 	struct sk_buff *skb;
317 	unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
318 
319 	skb = alloc_skb_fclone(buf_size, GFP_ATOMIC);
320 	if (skb) {
321 		skb_reserve(skb, BUF_HEADROOM);
322 		skb_put(skb, size);
323 		skb->next = NULL;
324 	}
325 	return skb;
326 }
327 
328 /**
329  * buf_discard - frees a TIPC message buffer
330  * @skb: message buffer
331  *
332  * Frees a message buffer.  If passed NULL, just returns.
333  */
334 
335 static inline void buf_discard(struct sk_buff *skb)
336 {
337 	kfree_skb(skb);
338 }
339 
340 /**
341  * buf_linearize - convert a TIPC message buffer into a single contiguous piece
342  * @skb: message buffer
343  *
344  * Returns 0 on success.
345  */
346 
347 static inline int buf_linearize(struct sk_buff *skb)
348 {
349 	return skb_linearize(skb);
350 }
351 
352 #endif
353