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) 2005-2006, 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
 184 static inline int delimit(int val, int min, int max)
 185 {
 186         if (val > max)
 187                 return max;
 188         if (val < min)
 189                 return min;
 190         return val;
 191 }
 192
 193
 194 /*
 195  * TIPC timer and signal code
 196  */
 197
 198 typedef void (*Handler) (unsigned long);
 199
 200 u32 tipc_k_signal(Handler routine, unsigned long argument);
 201
 202 /**
 203  * k_init_timer - initialize a timer
 204  * @timer: pointer to timer structure
 205  * @routine: pointer to routine to invoke when timer expires
 206  * @argument: value to pass to routine when timer expires
 207  *
 208  * Timer must be initialized before use (and terminated when no longer needed).
 209  */
 210
 211 static inline void k_init_timer(struct timer_list *timer, Handler routine,
 212                                 unsigned long argument)
 213 {
 214         dbg("initializing timer %p\n", timer);
 215         init_timer(timer);
 216         timer->function = routine;
 217         timer->data = argument;
 218 }
 219
 220 /**
 221  * k_start_timer - start a timer
 222  * @timer: pointer to timer structure
 223  * @msec: time to delay (in ms)
 224  *
 225  * Schedules a previously initialized timer for later execution.
 226  * If timer is already running, the new timeout overrides the previous request.
 227  *
 228  * To ensure the timer doesn't expire before the specified delay elapses,
 229  * the amount of delay is rounded up when converting to the jiffies
 230  * then an additional jiffy is added to account for the fact that
 231  * the starting time may be in the middle of the current jiffy.
 232  */
 233
 234 static inline void k_start_timer(struct timer_list *timer, unsigned long msec)
 235 {
 236         dbg("starting timer %p for %u\n", timer, msec);
 237         mod_timer(timer, jiffies + msecs_to_jiffies(msec) + 1);
 238 }
 239
 240 /**
 241  * k_cancel_timer - cancel a timer
 242  * @timer: pointer to timer structure
 243  *
 244  * Cancels a previously initialized timer.
 245  * Can be called safely even if the timer is already inactive.
 246  *
 247  * WARNING: Must not be called when holding locks required by the timer's
 248  *          timeout routine, otherwise deadlock can occur on SMP systems!
 249  */
 250
 251 static inline void k_cancel_timer(struct timer_list *timer)
 252 {
 253         dbg("cancelling timer %p\n", timer);
 254         del_timer_sync(timer);
 255 }
 256
 257 /**
 258  * k_term_timer - terminate a timer
 259  * @timer: pointer to timer structure
 260  *
 261  * Prevents further use of a previously initialized timer.
 262  *
 263  * WARNING: Caller must ensure timer isn't currently running.
 264  *
 265  * (Do not "enhance" this routine to automatically cancel an active timer,
 266  * otherwise deadlock can arise when a timeout routine calls k_term_timer.)
 267  */
 268
 269 static inline void k_term_timer(struct timer_list *timer)
 270 {
 271         dbg("terminating timer %p\n", timer);
 272 }
 273
 274
 275 /*
 276  * TIPC message buffer code
 277  *
 278  * TIPC message buffer headroom reserves space for a link-level header
 279  * (in case the message is sent off-node),
 280  * while ensuring TIPC header is word aligned for quicker access
 281  *
 282  * The largest header currently supported is 18 bytes, which is used when
 283  * the standard 14 byte Ethernet header has 4 added bytes for VLAN info
 284  */
 285
 286 #define BUF_HEADROOM 20u
 287
 288 struct tipc_skb_cb {
 289         void *handle;
 290 };
 291
 292 #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
 293
 294
 295 static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
 296 {
 297         return (struct tipc_msg *)skb->data;
 298 }
 299
 300 /**
 301  * buf_acquire - creates a TIPC message buffer
 302  * @size: message size (including TIPC header)
 303  *
 304  * Returns a new buffer with data pointers set to the specified size.
 305  *
 306  * NOTE: Headroom is reserved to allow prepending of a data link header.
 307  *       There may also be unrequested tailroom present at the buffer's end.
 308  */
 309
 310 static inline struct sk_buff *buf_acquire(u32 size)
 311 {
 312         struct sk_buff *skb;
 313         unsigned int buf_size = (BUF_HEADROOM + size + 3) & ~3u;
 314
 315         skb = alloc_skb(buf_size, GFP_ATOMIC);
 316         if (skb) {
 317                 skb_reserve(skb, BUF_HEADROOM);
 318                 skb_put(skb, size);
 319                 skb->next = NULL;
 320         }
 321         return skb;
 322 }
 323
 324 /**
 325  * buf_discard - frees a TIPC message buffer
 326  * @skb: message buffer
 327  *
 328  * Frees a message buffer.  If passed NULL, just returns.
 329  */
 330
 331 static inline void buf_discard(struct sk_buff *skb)
 332 {
 333         if (likely(skb != NULL))
 334                 kfree_skb(skb);
 335 }
 336
 337 #endif