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 atomic_notifier_head 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 extern void oops_enter(void);
  95 extern void oops_exit(void);
  96 extern int oops_may_print(void);
  97 fastcall NORET_TYPE void do_exit(long error_code)
  98         ATTRIB_NORET;
  99 NORET_TYPE void complete_and_exit(struct completion *, long)
 100         ATTRIB_NORET;
 101 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 102 extern long simple_strtol(const char *,char **,unsigned int);
 103 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 104 extern long long simple_strtoll(const char *,char **,unsigned int);
 105 extern int sprintf(char * buf, const char * fmt, ...)
 106         __attribute__ ((format (printf, 2, 3)));
 107 extern int vsprintf(char *buf, const char *, va_list)
 108         __attribute__ ((format (printf, 2, 0)));
 109 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 110         __attribute__ ((format (printf, 3, 4)));
 111 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 112         __attribute__ ((format (printf, 3, 0)));
 113 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 114         __attribute__ ((format (printf, 3, 4)));
 115 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 116         __attribute__ ((format (printf, 3, 0)));
 117
 118 extern int sscanf(const char *, const char *, ...)
 119         __attribute__ ((format (scanf, 2, 3)));
 120 extern int vsscanf(const char *, const char *, va_list)
 121         __attribute__ ((format (scanf, 2, 0)));
 122
 123 extern int get_option(char **str, int *pint);
 124 extern char *get_options(const char *str, int nints, int *ints);
 125 extern unsigned long long memparse(char *ptr, char **retptr);
 126
 127 extern int __kernel_text_address(unsigned long addr);
 128 extern int kernel_text_address(unsigned long addr);
 129 extern int session_of_pgrp(int pgrp);
 130
 131 extern void dump_thread(struct pt_regs *regs, struct user *dump);
 132
 133 #ifdef CONFIG_PRINTK
 134 asmlinkage int vprintk(const char *fmt, va_list args)
 135         __attribute__ ((format (printf, 1, 0)));
 136 asmlinkage int printk(const char * fmt, ...)
 137         __attribute__ ((format (printf, 1, 2)));
 138 #else
 139 static inline int vprintk(const char *s, va_list args)
 140         __attribute__ ((format (printf, 1, 0)));
 141 static inline int vprintk(const char *s, va_list args) { return 0; }
 142 static inline int printk(const char *s, ...)
 143         __attribute__ ((format (printf, 1, 2)));
 144 static inline int printk(const char *s, ...) { return 0; }
 145 #endif
 146
 147 unsigned long int_sqrt(unsigned long);
 148
 149 static inline int __attribute_pure__ long_log2(unsigned long x)
 150 {
 151         int r = 0;
 152         for (x >>= 1; x > 0; x >>= 1)
 153                 r++;
 154         return r;
 155 }
 156
 157 static inline unsigned long
 158 __attribute_const__ roundup_pow_of_two(unsigned long x)
 159 {
 160         return 1UL << fls_long(x - 1);
 161 }
 162
 163 extern int printk_ratelimit(void);
 164 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
 165
 166 static inline void console_silent(void)
 167 {
 168         console_loglevel = 0;
 169 }
 170
 171 static inline void console_verbose(void)
 172 {
 173         if (console_loglevel)
 174                 console_loglevel = 15;
 175 }
 176
 177 extern void bust_spinlocks(int yes);
 178 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 179 extern int panic_timeout;
 180 extern int panic_on_oops;
 181 extern int tainted;
 182 extern const char *print_tainted(void);
 183 extern void add_taint(unsigned);
 184
 185 /* Values used for system_state */
 186 extern enum system_states {
 187         SYSTEM_BOOTING,
 188         SYSTEM_RUNNING,
 189         SYSTEM_HALT,
 190         SYSTEM_POWER_OFF,
 191         SYSTEM_RESTART,
 192         SYSTEM_SUSPEND_DISK,
 193 } system_state;
 194
 195 #define TAINT_PROPRIETARY_MODULE        (1<<0)
 196 #define TAINT_FORCED_MODULE             (1<<1)
 197 #define TAINT_UNSAFE_SMP                (1<<2)
 198 #define TAINT_FORCED_RMMOD              (1<<3)
 199 #define TAINT_MACHINE_CHECK             (1<<4)
 200 #define TAINT_BAD_PAGE                  (1<<5)
 201
 202 extern void dump_stack(void);
 203
 204 #ifdef DEBUG
 205 #define pr_debug(fmt,arg...) \
 206         printk(KERN_DEBUG fmt,##arg)
 207 #else
 208 #define pr_debug(fmt,arg...) \
 209         do { } while (0)
 210 #endif
 211
 212 #define pr_info(fmt,arg...) \
 213         printk(KERN_INFO fmt,##arg)
 214
 215 /*
 216  *      Display an IP address in readable format.
 217  */
 218
 219 #define NIPQUAD(addr) \
 220         ((unsigned char *)&addr)[0], \
 221         ((unsigned char *)&addr)[1], \
 222         ((unsigned char *)&addr)[2], \
 223         ((unsigned char *)&addr)[3]
 224 #define NIPQUAD_FMT "%u.%u.%u.%u"
 225
 226 #define NIP6(addr) \
 227         ntohs((addr).s6_addr16[0]), \
 228         ntohs((addr).s6_addr16[1]), \
 229         ntohs((addr).s6_addr16[2]), \
 230         ntohs((addr).s6_addr16[3]), \
 231         ntohs((addr).s6_addr16[4]), \
 232         ntohs((addr).s6_addr16[5]), \
 233         ntohs((addr).s6_addr16[6]), \
 234         ntohs((addr).s6_addr16[7])
 235 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 236 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
 237
 238 #if defined(__LITTLE_ENDIAN)
 239 #define HIPQUAD(addr) \
 240         ((unsigned char *)&addr)[3], \
 241         ((unsigned char *)&addr)[2], \
 242         ((unsigned char *)&addr)[1], \
 243         ((unsigned char *)&addr)[0]
 244 #elif defined(__BIG_ENDIAN)
 245 #define HIPQUAD NIPQUAD
 246 #else
 247 #error "Please fix asm/byteorder.h"
 248 #endif /* __LITTLE_ENDIAN */
 249
 250 /*
 251  * min()/max() macros that also do
 252  * strict type-checking.. See the
 253  * "unnecessary" pointer comparison.
 254  */
 255 #define min(x,y) ({ \
 256         typeof(x) _x = (x);     \
 257         typeof(y) _y = (y);     \
 258         (void) (&_x == &_y);            \
 259         _x < _y ? _x : _y; })
 260
 261 #define max(x,y) ({ \
 262         typeof(x) _x = (x);     \
 263         typeof(y) _y = (y);     \
 264         (void) (&_x == &_y);            \
 265         _x > _y ? _x : _y; })
 266
 267 /*
 268  * ..and if you can't take the strict
 269  * types, you can specify one yourself.
 270  *
 271  * Or not use min/max at all, of course.
 272  */
 273 #define min_t(type,x,y) \
 274         ({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
 275 #define max_t(type,x,y) \
 276         ({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 277
 278
 279 /**
 280  * container_of - cast a member of a structure out to the containing structure
 281  * @ptr:        the pointer to the member.
 282  * @type:       the type of the container struct this is embedded in.
 283  * @member:     the name of the member within the struct.
 284  *
 285  */
 286 #define container_of(ptr, type, member) ({                      \
 287         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 288         (type *)( (char *)__mptr - offsetof(type,member) );})
 289
 290 /*
 291  * Check at compile time that something is of a particular type.
 292  * Always evaluates to 1 so you may use it easily in comparisons.
 293  */
 294 #define typecheck(type,x) \
 295 ({      type __dummy; \
 296         typeof(x) __dummy2; \
 297         (void)(&__dummy == &__dummy2); \
 298         1; \
 299 })
 300
 301 /*
 302  * Check at compile time that 'function' is a certain type, or is a pointer
 303  * to that type (needs to use typedef for the function type.)
 304  */
 305 #define typecheck_fn(type,function) \
 306 ({      typeof(type) __tmp = function; \
 307         (void)__tmp; \
 308 })
 309
 310 #endif /* __KERNEL__ */
 311
 312 #define SI_LOAD_SHIFT   16
 313 struct sysinfo {
 314         long uptime;                    /* Seconds since boot */
 315         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 316         unsigned long totalram;         /* Total usable main memory size */
 317         unsigned long freeram;          /* Available memory size */
 318         unsigned long sharedram;        /* Amount of shared memory */
 319         unsigned long bufferram;        /* Memory used by buffers */
 320         unsigned long totalswap;        /* Total swap space size */
 321         unsigned long freeswap;         /* swap space still available */
 322         unsigned short procs;           /* Number of current processes */
 323         unsigned short pad;             /* explicit padding for m68k */
 324         unsigned long totalhigh;        /* Total high memory size */
 325         unsigned long freehigh;         /* Available high memory size */
 326         unsigned int mem_unit;          /* Memory unit size in bytes */
 327         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 328 };
 329
 330 /* Force a compilation error if condition is true */
 331 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 332
 333 /* Trap pasters of __FUNCTION__ at compile-time */
 334 #define __FUNCTION__ (__func__)
 335
 336 #endif