include/linux/kernel.h

   1 #ifndef _LINUX_KERNEL_H
   2 #define _LINUX_KERNEL_H
   3
   4 /*
   5  * 'kernel.h' contains some often-used function prototypes etc
   6  */
   7
   8 #ifdef __KERNEL__
   9
  10 #include <stdarg.h>
  11 #include <linux/linkage.h>
  12 #include <linux/stddef.h>
  13 #include <linux/types.h>
  14 #include <linux/compiler.h>
  15 #include <linux/bitops.h>
  16 #include <asm/byteorder.h>
  17 #include <asm/bug.h>
  18
  19 extern const char linux_banner[];
  20
  21 #define INT_MAX         ((int)(~0U>>1))
  22 #define INT_MIN         (-INT_MAX - 1)
  23 #define UINT_MAX        (~0U)
  24 #define LONG_MAX        ((long)(~0UL>>1))
  25 #define LONG_MIN        (-LONG_MAX - 1)
  26 #define ULONG_MAX       (~0UL)
  27
  28 #define STACK_MAGIC     0xdeadbeef
  29
  30 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  31 #define ALIGN(x,a) (((x)+(a)-1)&~((a)-1))
  32
  33 #define KERN_EMERG      "<0>"   /* system is unusable                   */
  34 #define KERN_ALERT      "<1>"   /* action must be taken immediately     */
  35 #define KERN_CRIT       "<2>"   /* critical conditions                  */
  36 #define KERN_ERR        "<3>"   /* error conditions                     */
  37 #define KERN_WARNING    "<4>"   /* warning conditions                   */
  38 #define KERN_NOTICE     "<5>"   /* normal but significant condition     */
  39 #define KERN_INFO       "<6>"   /* informational                        */
  40 #define KERN_DEBUG      "<7>"   /* debug-level messages                 */
  41
  42 extern int console_printk[];
  43
  44 #define console_loglevel (console_printk[0])
  45 #define default_message_loglevel (console_printk[1])
  46 #define minimum_console_loglevel (console_printk[2])
  47 #define default_console_loglevel (console_printk[3])
  48
  49 struct completion;
  50
  51 /**
  52  * might_sleep - annotation for functions that can sleep
  53  *
  54  * this macro will print a stack trace if it is executed in an atomic
  55  * context (spinlock, irq-handler, ...).
  56  *
  57  * This is a useful debugging help to be able to catch problems early and not
  58  * be biten later when the calling function happens to sleep when it is not
  59  * supposed to.
  60  */
  61 #ifdef CONFIG_PREEMPT_VOLUNTARY
  62 extern int cond_resched(void);
  63 # define might_resched() cond_resched()
  64 #else
  65 # define might_resched() do { } while (0)
  66 #endif
  67
  68 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  69   void __might_sleep(char *file, int line);
  70 # define might_sleep() \
  71         do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
  72 #else
  73 # define might_sleep() do { might_resched(); } while (0)
  74 #endif
  75
  76 #define might_sleep_if(cond) do { if (unlikely(cond)) might_sleep(); } while (0)
  77
  78 #define abs(x) ({                               \
  79                 int __x = (x);                  \
  80                 (__x < 0) ? -__x : __x;         \
  81         })
  82
  83 #define labs(x) ({                              \
  84                 long __x = (x);                 \
  85                 (__x < 0) ? -__x : __x;         \
  86         })
  87
  88 extern struct notifier_block *panic_notifier_list;
  89 extern long (*panic_blink)(long time);
  90 NORET_TYPE void panic(const char * fmt, ...)
  91         __attribute__ ((NORET_AND format (printf, 1, 2)));
  92 fastcall NORET_TYPE void do_exit(long error_code)
  93         ATTRIB_NORET;
  94 NORET_TYPE void complete_and_exit(struct completion *, long)
  95         ATTRIB_NORET;
  96 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
  97 extern long simple_strtol(const char *,char **,unsigned int);
  98 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
  99 extern long long simple_strtoll(const char *,char **,unsigned int);
 100 extern int sprintf(char * buf, const char * fmt, ...)
 101         __attribute__ ((format (printf, 2, 3)));
 102 extern int vsprintf(char *buf, const char *, va_list)
 103         __attribute__ ((format (printf, 2, 0)));
 104 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 105         __attribute__ ((format (printf, 3, 4)));
 106 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 107         __attribute__ ((format (printf, 3, 0)));
 108 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 109         __attribute__ ((format (printf, 3, 4)));
 110 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 111         __attribute__ ((format (printf, 3, 0)));
 112
 113 extern int sscanf(const char *, const char *, ...)
 114         __attribute__ ((format (scanf, 2, 3)));
 115 extern int vsscanf(const char *, const char *, va_list)
 116         __attribute__ ((format (scanf, 2, 0)));
 117
 118 extern int get_option(char **str, int *pint);
 119 extern char *get_options(const char *str, int nints, int *ints);
 120 extern unsigned long long memparse(char *ptr, char **retptr);
 121
 122 extern int __kernel_text_address(unsigned long addr);
 123 extern int kernel_text_address(unsigned long addr);
 124 extern int session_of_pgrp(int pgrp);
 125
 126 #ifdef CONFIG_PRINTK
 127 asmlinkage int vprintk(const char *fmt, va_list args)
 128         __attribute__ ((format (printf, 1, 0)));
 129 asmlinkage int printk(const char * fmt, ...)
 130         __attribute__ ((format (printf, 1, 2)));
 131 #else
 132 static inline int vprintk(const char *s, va_list args)
 133         __attribute__ ((format (printf, 1, 0)));
 134 static inline int vprintk(const char *s, va_list args) { return 0; }
 135 static inline int printk(const char *s, ...)
 136         __attribute__ ((format (printf, 1, 2)));
 137 static inline int printk(const char *s, ...) { return 0; }
 138 #endif
 139
 140 unsigned long int_sqrt(unsigned long);
 141
 142 static inline int __attribute_pure__ long_log2(unsigned long x)
 143 {
 144         int r = 0;
 145         for (x >>= 1; x > 0; x >>= 1)
 146                 r++;
 147         return r;
 148 }
 149
 150 static inline unsigned long __attribute_const__ roundup_pow_of_two(unsigned long x)
 151 {
 152         return (1UL << fls(x - 1));
 153 }
 154
 155 extern int printk_ratelimit(void);
 156 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
 157
 158 static inline void console_silent(void)
 159 {
 160         console_loglevel = 0;
 161 }
 162
 163 static inline void console_verbose(void)
 164 {
 165         if (console_loglevel)
 166                 console_loglevel = 15;
 167 }
 168
 169 extern void bust_spinlocks(int yes);
 170 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 171 extern __deprecated_for_modules int panic_timeout;
 172 extern int panic_on_oops;
 173 extern int tainted;
 174 extern const char *print_tainted(void);
 175 extern void add_taint(unsigned);
 176
 177 /* Values used for system_state */
 178 extern enum system_states {
 179         SYSTEM_BOOTING,
 180         SYSTEM_RUNNING,
 181         SYSTEM_HALT,
 182         SYSTEM_POWER_OFF,
 183         SYSTEM_RESTART,
 184 } system_state;
 185
 186 #define TAINT_PROPRIETARY_MODULE        (1<<0)
 187 #define TAINT_FORCED_MODULE             (1<<1)
 188 #define TAINT_UNSAFE_SMP                (1<<2)
 189 #define TAINT_FORCED_RMMOD              (1<<3)
 190 #define TAINT_MACHINE_CHECK             (1<<4)
 191 #define TAINT_BAD_PAGE                  (1<<5)
 192
 193 extern void dump_stack(void);
 194
 195 #ifdef DEBUG
 196 #define pr_debug(fmt,arg...) \
 197         printk(KERN_DEBUG fmt,##arg)
 198 #else
 199 #define pr_debug(fmt,arg...) \
 200         do { } while (0)
 201 #endif
 202
 203 #define pr_info(fmt,arg...) \
 204         printk(KERN_INFO fmt,##arg)
 205
 206 /*
 207  *      Display an IP address in readable format.
 208  */
 209
 210 #define NIPQUAD(addr) \
 211         ((unsigned char *)&addr)[0], \
 212         ((unsigned char *)&addr)[1], \
 213         ((unsigned char *)&addr)[2], \
 214         ((unsigned char *)&addr)[3]
 215
 216 #define NIP6(addr) \
 217         ntohs((addr).s6_addr16[0]), \
 218         ntohs((addr).s6_addr16[1]), \
 219         ntohs((addr).s6_addr16[2]), \
 220         ntohs((addr).s6_addr16[3]), \
 221         ntohs((addr).s6_addr16[4]), \
 222         ntohs((addr).s6_addr16[5]), \
 223         ntohs((addr).s6_addr16[6]), \
 224         ntohs((addr).s6_addr16[7])
 225
 226 #if defined(__LITTLE_ENDIAN)
 227 #define HIPQUAD(addr) \
 228         ((unsigned char *)&addr)[3], \
 229         ((unsigned char *)&addr)[2], \
 230         ((unsigned char *)&addr)[1], \
 231         ((unsigned char *)&addr)[0]
 232 #elif defined(__BIG_ENDIAN)
 233 #define HIPQUAD NIPQUAD
 234 #else
 235 #error "Please fix asm/byteorder.h"
 236 #endif /* __LITTLE_ENDIAN */
 237
 238 /*
 239  * min()/max() macros that also do
 240  * strict type-checking.. See the
 241  * "unnecessary" pointer comparison.
 242  */
 243 #define min(x,y) ({ \
 244         typeof(x) _x = (x);     \
 245         typeof(y) _y = (y);     \
 246         (void) (&_x == &_y);            \
 247         _x < _y ? _x : _y; })
 248
 249 #define max(x,y) ({ \
 250         typeof(x) _x = (x);     \
 251         typeof(y) _y = (y);     \
 252         (void) (&_x == &_y);            \
 253         _x > _y ? _x : _y; })
 254
 255 /*
 256  * ..and if you can't take the strict
 257  * types, you can specify one yourself.
 258  *
 259  * Or not use min/max at all, of course.
 260  */
 261 #define min_t(type,x,y) \
 262         ({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
 263 #define max_t(type,x,y) \
 264         ({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 265
 266
 267 /**
 268  * container_of - cast a member of a structure out to the containing structure
 269  * @ptr:        the pointer to the member.
 270  * @type:       the type of the container struct this is embedded in.
 271  * @member:     the name of the member within the struct.
 272  *
 273  */
 274 #define container_of(ptr, type, member) ({                      \
 275         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 276         (type *)( (char *)__mptr - offsetof(type,member) );})
 277
 278 /*
 279  * Check at compile time that something is of a particular type.
 280  * Always evaluates to 1 so you may use it easily in comparisons.
 281  */
 282 #define typecheck(type,x) \
 283 ({      type __dummy; \
 284         typeof(x) __dummy2; \
 285         (void)(&__dummy == &__dummy2); \
 286         1; \
 287 })
 288
 289 #endif /* __KERNEL__ */
 290
 291 #define SI_LOAD_SHIFT   16
 292 struct sysinfo {
 293         long uptime;                    /* Seconds since boot */
 294         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 295         unsigned long totalram;         /* Total usable main memory size */
 296         unsigned long freeram;          /* Available memory size */
 297         unsigned long sharedram;        /* Amount of shared memory */
 298         unsigned long bufferram;        /* Memory used by buffers */
 299         unsigned long totalswap;        /* Total swap space size */
 300         unsigned long freeswap;         /* swap space still available */
 301         unsigned short procs;           /* Number of current processes */
 302         unsigned short pad;             /* explicit padding for m68k */
 303         unsigned long totalhigh;        /* Total high memory size */
 304         unsigned long freehigh;         /* Available high memory size */
 305         unsigned int mem_unit;          /* Memory unit size in bytes */
 306         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 307 };
 308
 309 /* Force a compilation error if condition is true */
 310 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 311
 312 #ifdef CONFIG_SYSCTL
 313 extern int randomize_va_space;
 314 #else
 315 #define randomize_va_space 1
 316 #endif
 317
 318 /* Trap pasters of __FUNCTION__ at compile-time */
 319 #if __GNUC__ > 2 || __GNUC_MINOR__ >= 95
 320 #define __FUNCTION__ (__func__)
 321 #endif
 322
 323 #endif