/net/tipc/core.h

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