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
  84 extern struct print_buf *const TIPC_NULL;
  85 extern struct print_buf *const TIPC_CONS;
  86 extern struct print_buf *const TIPC_LOG;
  87
  88 void 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
 154 void tipc_msg_dbg(struct print_buf *, struct tipc_msg *, const char *);
 155 void 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
 179 extern u32 tipc_own_addr;
 180 extern int tipc_max_zones;
 181 extern int tipc_max_clusters;
 182 extern int tipc_max_nodes;
 183 extern int tipc_max_slaves;
 184 extern int tipc_max_ports;
 185 extern int tipc_max_subscriptions;
 186 extern int tipc_max_publications;
 187 extern int tipc_net_id;
 188 extern int tipc_remote_management;
 189
 190 /*
 191  * Other global variables
 192  */
 193
 194 extern int tipc_mode;
 195 extern int tipc_random;
 196 extern const char tipc_alphabet[];
 197 extern atomic_t tipc_user_count;
 198
 199
 200 /*
 201  * Routines available to privileged subsystems
 202  */
 203
 204 extern int  tipc_core_start(void);
 205 extern void tipc_core_stop(void);
 206 extern int  tipc_core_start_net(unsigned long addr);
 207 extern void tipc_core_stop_net(void);
 208 extern int  tipc_handler_start(void);
 209 extern void tipc_handler_stop(void);
 210 extern int  tipc_netlink_start(void);
 211 extern void tipc_netlink_stop(void);
 212 extern int  tipc_socket_init(void);
 213 extern void tipc_socket_stop(void);
 214
 215 static 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
 229 typedef void (*Handler) (unsigned long);
 230
 231 u32 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
 242 static 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
 263 static 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
 280 static 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
 298 static 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
 316 struct tipc_skb_cb {
 317         void *handle;
 318 };
 319
 320 #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
 321
 322
 323 static 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
 338 static 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
 359 static 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
 371 static inline int buf_linearize(struct sk_buff *skb)
 372 {
 373         return skb_linearize(skb);
 374 }
 375
 376 #endif