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/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