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 struct pt_regs;
  51 struct user;
  52
  53 /**
  54  * might_sleep - annotation for functions that can sleep
  55  *
  56  * this macro will print a stack trace if it is executed in an atomic
  57  * context (spinlock, irq-handler, ...).
  58  *
  59  * This is a useful debugging help to be able to catch problems early and not
  60  * be biten later when the calling function happens to sleep when it is not
  61  * supposed to.
  62  */
  63 #ifdef CONFIG_PREEMPT_VOLUNTARY
  64 extern int cond_resched(void);
  65 # define might_resched() cond_resched()
  66 #else
  67 # define might_resched() do { } while (0)
  68 #endif
  69
  70 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  71   void __might_sleep(char *file, int line);
  72 # define might_sleep() \
  73         do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
  74 #else
  75 # define might_sleep() do { might_resched(); } while (0)
  76 #endif
  77
  78 #define might_sleep_if(cond) do { if (unlikely(cond)) might_sleep(); } while (0)
  79
  80 #define abs(x) ({                               \
  81                 int __x = (x);                  \
  82                 (__x < 0) ? -__x : __x;         \
  83         })
  84
  85 #define labs(x) ({                              \
  86                 long __x = (x);                 \
  87                 (__x < 0) ? -__x : __x;         \
  88         })
  89
  90 extern struct notifier_block *panic_notifier_list;
  91 extern long (*panic_blink)(long time);
  92 NORET_TYPE void panic(const char * fmt, ...)
  93         __attribute__ ((NORET_AND format (printf, 1, 2)));
  94 fastcall NORET_TYPE void do_exit(long error_code)
  95         ATTRIB_NORET;
  96 NORET_TYPE void complete_and_exit(struct completion *, long)
  97         ATTRIB_NORET;
  98 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
  99 extern long simple_strtol(const char *,char **,unsigned int);
 100 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 101 extern long long simple_strtoll(const char *,char **,unsigned int);
 102 extern int sprintf(char * buf, const char * fmt, ...)
 103         __attribute__ ((format (printf, 2, 3)));
 104 extern int vsprintf(char *buf, const char *, va_list)
 105         __attribute__ ((format (printf, 2, 0)));
 106 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 107         __attribute__ ((format (printf, 3, 4)));
 108 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 109         __attribute__ ((format (printf, 3, 0)));
 110 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 111         __attribute__ ((format (printf, 3, 4)));
 112 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 113         __attribute__ ((format (printf, 3, 0)));
 114
 115 extern int sscanf(const char *, const char *, ...)
 116         __attribute__ ((format (scanf, 2, 3)));
 117 extern int vsscanf(const char *, const char *, va_list)
 118         __attribute__ ((format (scanf, 2, 0)));
 119
 120 extern int get_option(char **str, int *pint);
 121 extern char *get_options(const char *str, int nints, int *ints);
 122 extern unsigned long long memparse(char *ptr, char **retptr);
 123
 124 extern int __kernel_text_address(unsigned long addr);
 125 extern int kernel_text_address(unsigned long addr);
 126 extern int session_of_pgrp(int pgrp);
 127
 128 extern void dump_thread(struct pt_regs *regs, struct user *dump);
 129
 130 #ifdef CONFIG_PRINTK
 131 asmlinkage int vprintk(const char *fmt, va_list args)
 132         __attribute__ ((format (printf, 1, 0)));
 133 asmlinkage int printk(const char * fmt, ...)
 134         __attribute__ ((format (printf, 1, 2)));
 135 #else
 136 static inline int vprintk(const char *s, va_list args)
 137         __attribute__ ((format (printf, 1, 0)));
 138 static inline int vprintk(const char *s, va_list args) { return 0; }
 139 static inline int printk(const char *s, ...)
 140         __attribute__ ((format (printf, 1, 2)));
 141 static inline int printk(const char *s, ...) { return 0; }
 142 #endif
 143
 144 unsigned long int_sqrt(unsigned long);
 145
 146 static inline int __attribute_pure__ long_log2(unsigned long x)
 147 {
 148         int r = 0;
 149         for (x >>= 1; x > 0; x >>= 1)
 150                 r++;
 151         return r;
 152 }
 153
 154 static inline unsigned long __attribute_const__ roundup_pow_of_two(unsigned long x)
 155 {
 156         return (1UL << fls(x - 1));
 157 }
 158
 159 extern int printk_ratelimit(void);
 160 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
 161
 162 static inline void console_silent(void)
 163 {
 164         console_loglevel = 0;
 165 }
 166
 167 static inline void console_verbose(void)
 168 {
 169         if (console_loglevel)
 170                 console_loglevel = 15;
 171 }
 172
 173 extern void bust_spinlocks(int yes);
 174 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 175 extern __deprecated_for_modules int panic_timeout;
 176 extern int panic_on_oops;
 177 extern int tainted;
 178 extern const char *print_tainted(void);
 179 extern void add_taint(unsigned);
 180
 181 /* Values used for system_state */
 182 extern enum system_states {
 183         SYSTEM_BOOTING,
 184         SYSTEM_RUNNING,
 185         SYSTEM_HALT,
 186         SYSTEM_POWER_OFF,
 187         SYSTEM_RESTART,
 188         SYSTEM_SUSPEND_DISK,
 189 } system_state;
 190
 191 #define TAINT_PROPRIETARY_MODULE        (1<<0)
 192 #define TAINT_FORCED_MODULE             (1<<1)
 193 #define TAINT_UNSAFE_SMP                (1<<2)
 194 #define TAINT_FORCED_RMMOD              (1<<3)
 195 #define TAINT_MACHINE_CHECK             (1<<4)
 196 #define TAINT_BAD_PAGE                  (1<<5)
 197
 198 extern void dump_stack(void);
 199
 200 #ifdef DEBUG
 201 #define pr_debug(fmt,arg...) \
 202         printk(KERN_DEBUG fmt,##arg)
 203 #else
 204 #define pr_debug(fmt,arg...) \
 205         do { } while (0)
 206 #endif
 207
 208 #define pr_info(fmt,arg...) \
 209         printk(KERN_INFO fmt,##arg)
 210
 211 /*
 212  *      Display an IP address in readable format.
 213  */
 214
 215 #define NIPQUAD(addr) \
 216         ((unsigned char *)&addr)[0], \
 217         ((unsigned char *)&addr)[1], \
 218         ((unsigned char *)&addr)[2], \
 219         ((unsigned char *)&addr)[3]
 220 #define NIPQUAD_FMT "%u.%u.%u.%u"
 221
 222 #define NIP6(addr) \
 223         ntohs((addr).s6_addr16[0]), \
 224         ntohs((addr).s6_addr16[1]), \
 225         ntohs((addr).s6_addr16[2]), \
 226         ntohs((addr).s6_addr16[3]), \
 227         ntohs((addr).s6_addr16[4]), \
 228         ntohs((addr).s6_addr16[5]), \
 229         ntohs((addr).s6_addr16[6]), \
 230         ntohs((addr).s6_addr16[7])
 231 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 232 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
 233
 234 #if defined(__LITTLE_ENDIAN)
 235 #define HIPQUAD(addr) \
 236         ((unsigned char *)&addr)[3], \
 237         ((unsigned char *)&addr)[2], \
 238         ((unsigned char *)&addr)[1], \
 239         ((unsigned char *)&addr)[0]
 240 #elif defined(__BIG_ENDIAN)
 241 #define HIPQUAD NIPQUAD
 242 #else
 243 #error "Please fix asm/byteorder.h"
 244 #endif /* __LITTLE_ENDIAN */
 245
 246 /*
 247  * min()/max() macros that also do
 248  * strict type-checking.. See the
 249  * "unnecessary" pointer comparison.
 250  */
 251 #define min(x,y) ({ \
 252         typeof(x) _x = (x);     \
 253         typeof(y) _y = (y);     \
 254         (void) (&_x == &_y);            \
 255         _x < _y ? _x : _y; })
 256
 257 #define max(x,y) ({ \
 258         typeof(x) _x = (x);     \
 259         typeof(y) _y = (y);     \
 260         (void) (&_x == &_y);            \
 261         _x > _y ? _x : _y; })
 262
 263 /*
 264  * ..and if you can't take the strict
 265  * types, you can specify one yourself.
 266  *
 267  * Or not use min/max at all, of course.
 268  */
 269 #define min_t(type,x,y) \
 270         ({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
 271 #define max_t(type,x,y) \
 272         ({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 273
 274
 275 /**
 276  * container_of - cast a member of a structure out to the containing structure
 277  * @ptr:        the pointer to the member.
 278  * @type:       the type of the container struct this is embedded in.
 279  * @member:     the name of the member within the struct.
 280  *
 281  */
 282 #define container_of(ptr, type, member) ({                      \
 283         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 284         (type *)( (char *)__mptr - offsetof(type,member) );})
 285
 286 /*
 287  * Check at compile time that something is of a particular type.
 288  * Always evaluates to 1 so you may use it easily in comparisons.
 289  */
 290 #define typecheck(type,x) \
 291 ({      type __dummy; \
 292         typeof(x) __dummy2; \
 293         (void)(&__dummy == &__dummy2); \
 294         1; \
 295 })
 296
 297 /*
 298  * Check at compile time that 'function' is a certain type, or is a pointer
 299  * to that type (needs to use typedef for the function type.)
 300  */
 301 #define typecheck_fn(type,function) \
 302 ({      typeof(type) __tmp = function; \
 303         (void)__tmp; \
 304 })
 305
 306 #endif /* __KERNEL__ */
 307
 308 #define SI_LOAD_SHIFT   16
 309 struct sysinfo {
 310         long uptime;                    /* Seconds since boot */
 311         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 312         unsigned long totalram;         /* Total usable main memory size */
 313         unsigned long freeram;          /* Available memory size */
 314         unsigned long sharedram;        /* Amount of shared memory */
 315         unsigned long bufferram;        /* Memory used by buffers */
 316         unsigned long totalswap;        /* Total swap space size */
 317         unsigned long freeswap;         /* swap space still available */
 318         unsigned short procs;           /* Number of current processes */
 319         unsigned short pad;             /* explicit padding for m68k */
 320         unsigned long totalhigh;        /* Total high memory size */
 321         unsigned long freehigh;         /* Available high memory size */
 322         unsigned int mem_unit;          /* Memory unit size in bytes */
 323         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 324 };
 325
 326 /* Force a compilation error if condition is true */
 327 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 328
 329 /* Trap pasters of __FUNCTION__ at compile-time */
 330 #define __FUNCTION__ (__func__)
 331
 332 #endif