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 #define LLONG_MAX       ((long long)(~0ULL>>1))
  28 #define LLONG_MIN       (-LLONG_MAX - 1)
  29 #define ULLONG_MAX      (~0ULL)
  30
  31 #define STACK_MAGIC     0xdeadbeef
  32
  33 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  34 #define ALIGN(x,a) (((x)+(a)-1)&~((a)-1))
  35
  36 #define KERN_EMERG      "<0>"   /* system is unusable                   */
  37 #define KERN_ALERT      "<1>"   /* action must be taken immediately     */
  38 #define KERN_CRIT       "<2>"   /* critical conditions                  */
  39 #define KERN_ERR        "<3>"   /* error conditions                     */
  40 #define KERN_WARNING    "<4>"   /* warning conditions                   */
  41 #define KERN_NOTICE     "<5>"   /* normal but significant condition     */
  42 #define KERN_INFO       "<6>"   /* informational                        */
  43 #define KERN_DEBUG      "<7>"   /* debug-level messages                 */
  44
  45 extern int console_printk[];
  46
  47 #define console_loglevel (console_printk[0])
  48 #define default_message_loglevel (console_printk[1])
  49 #define minimum_console_loglevel (console_printk[2])
  50 #define default_console_loglevel (console_printk[3])
  51
  52 struct completion;
  53 struct pt_regs;
  54 struct user;
  55
  56 /**
  57  * might_sleep - annotation for functions that can sleep
  58  *
  59  * this macro will print a stack trace if it is executed in an atomic
  60  * context (spinlock, irq-handler, ...).
  61  *
  62  * This is a useful debugging help to be able to catch problems early and not
  63  * be biten later when the calling function happens to sleep when it is not
  64  * supposed to.
  65  */
  66 #ifdef CONFIG_PREEMPT_VOLUNTARY
  67 extern int cond_resched(void);
  68 # define might_resched() cond_resched()
  69 #else
  70 # define might_resched() do { } while (0)
  71 #endif
  72
  73 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  74   void __might_sleep(char *file, int line);
  75 # define might_sleep() \
  76         do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
  77 #else
  78 # define might_sleep() do { might_resched(); } while (0)
  79 #endif
  80
  81 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
  82
  83 #define abs(x) ({                               \
  84                 int __x = (x);                  \
  85                 (__x < 0) ? -__x : __x;         \
  86         })
  87
  88 #define labs(x) ({                              \
  89                 long __x = (x);                 \
  90                 (__x < 0) ? -__x : __x;         \
  91         })
  92
  93 extern struct atomic_notifier_head panic_notifier_list;
  94 extern long (*panic_blink)(long time);
  95 NORET_TYPE void panic(const char * fmt, ...)
  96         __attribute__ ((NORET_AND format (printf, 1, 2)));
  97 extern void oops_enter(void);
  98 extern void oops_exit(void);
  99 extern int oops_may_print(void);
 100 fastcall NORET_TYPE void do_exit(long error_code)
 101         ATTRIB_NORET;
 102 NORET_TYPE void complete_and_exit(struct completion *, long)
 103         ATTRIB_NORET;
 104 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 105 extern long simple_strtol(const char *,char **,unsigned int);
 106 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 107 extern long long simple_strtoll(const char *,char **,unsigned int);
 108 extern int sprintf(char * buf, const char * fmt, ...)
 109         __attribute__ ((format (printf, 2, 3)));
 110 extern int vsprintf(char *buf, const char *, va_list)
 111         __attribute__ ((format (printf, 2, 0)));
 112 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 113         __attribute__ ((format (printf, 3, 4)));
 114 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 115         __attribute__ ((format (printf, 3, 0)));
 116 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 117         __attribute__ ((format (printf, 3, 4)));
 118 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 119         __attribute__ ((format (printf, 3, 0)));
 120
 121 extern int sscanf(const char *, const char *, ...)
 122         __attribute__ ((format (scanf, 2, 3)));
 123 extern int vsscanf(const char *, const char *, va_list)
 124         __attribute__ ((format (scanf, 2, 0)));
 125
 126 extern int get_option(char **str, int *pint);
 127 extern char *get_options(const char *str, int nints, int *ints);
 128 extern unsigned long long memparse(char *ptr, char **retptr);
 129
 130 extern int core_kernel_text(unsigned long addr);
 131 extern int __kernel_text_address(unsigned long addr);
 132 extern int kernel_text_address(unsigned long addr);
 133 extern int session_of_pgrp(int pgrp);
 134
 135 extern void dump_thread(struct pt_regs *regs, struct user *dump);
 136
 137 #ifdef CONFIG_PRINTK
 138 asmlinkage int vprintk(const char *fmt, va_list args)
 139         __attribute__ ((format (printf, 1, 0)));
 140 asmlinkage int printk(const char * fmt, ...)
 141         __attribute__ ((format (printf, 1, 2)));
 142 #else
 143 static inline int vprintk(const char *s, va_list args)
 144         __attribute__ ((format (printf, 1, 0)));
 145 static inline int vprintk(const char *s, va_list args) { return 0; }
 146 static inline int printk(const char *s, ...)
 147         __attribute__ ((format (printf, 1, 2)));
 148 static inline int printk(const char *s, ...) { return 0; }
 149 #endif
 150
 151 unsigned long int_sqrt(unsigned long);
 152
 153 static inline int __attribute_pure__ long_log2(unsigned long x)
 154 {
 155         int r = 0;
 156         for (x >>= 1; x > 0; x >>= 1)
 157                 r++;
 158         return r;
 159 }
 160
 161 static inline unsigned long
 162 __attribute_const__ roundup_pow_of_two(unsigned long x)
 163 {
 164         return 1UL << fls_long(x - 1);
 165 }
 166
 167 extern int printk_ratelimit(void);
 168 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
 169
 170 static inline void console_silent(void)
 171 {
 172         console_loglevel = 0;
 173 }
 174
 175 static inline void console_verbose(void)
 176 {
 177         if (console_loglevel)
 178                 console_loglevel = 15;
 179 }
 180
 181 extern void bust_spinlocks(int yes);
 182 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 183 extern int panic_timeout;
 184 extern int panic_on_oops;
 185 extern int tainted;
 186 extern const char *print_tainted(void);
 187 extern void add_taint(unsigned);
 188
 189 /* Values used for system_state */
 190 extern enum system_states {
 191         SYSTEM_BOOTING,
 192         SYSTEM_RUNNING,
 193         SYSTEM_HALT,
 194         SYSTEM_POWER_OFF,
 195         SYSTEM_RESTART,
 196         SYSTEM_SUSPEND_DISK,
 197 } system_state;
 198
 199 #define TAINT_PROPRIETARY_MODULE        (1<<0)
 200 #define TAINT_FORCED_MODULE             (1<<1)
 201 #define TAINT_UNSAFE_SMP                (1<<2)
 202 #define TAINT_FORCED_RMMOD              (1<<3)
 203 #define TAINT_MACHINE_CHECK             (1<<4)
 204 #define TAINT_BAD_PAGE                  (1<<5)
 205
 206 extern void dump_stack(void);
 207
 208 #ifdef DEBUG
 209 #define pr_debug(fmt,arg...) \
 210         printk(KERN_DEBUG fmt,##arg)
 211 #else
 212 #define pr_debug(fmt,arg...) \
 213         do { } while (0)
 214 #endif
 215
 216 #define pr_info(fmt,arg...) \
 217         printk(KERN_INFO fmt,##arg)
 218
 219 /*
 220  *      Display an IP address in readable format.
 221  */
 222
 223 #define NIPQUAD(addr) \
 224         ((unsigned char *)&addr)[0], \
 225         ((unsigned char *)&addr)[1], \
 226         ((unsigned char *)&addr)[2], \
 227         ((unsigned char *)&addr)[3]
 228 #define NIPQUAD_FMT "%u.%u.%u.%u"
 229
 230 #define NIP6(addr) \
 231         ntohs((addr).s6_addr16[0]), \
 232         ntohs((addr).s6_addr16[1]), \
 233         ntohs((addr).s6_addr16[2]), \
 234         ntohs((addr).s6_addr16[3]), \
 235         ntohs((addr).s6_addr16[4]), \
 236         ntohs((addr).s6_addr16[5]), \
 237         ntohs((addr).s6_addr16[6]), \
 238         ntohs((addr).s6_addr16[7])
 239 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 240 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
 241
 242 #if defined(__LITTLE_ENDIAN)
 243 #define HIPQUAD(addr) \
 244         ((unsigned char *)&addr)[3], \
 245         ((unsigned char *)&addr)[2], \
 246         ((unsigned char *)&addr)[1], \
 247         ((unsigned char *)&addr)[0]
 248 #elif defined(__BIG_ENDIAN)
 249 #define HIPQUAD NIPQUAD
 250 #else
 251 #error "Please fix asm/byteorder.h"
 252 #endif /* __LITTLE_ENDIAN */
 253
 254 /*
 255  * min()/max() macros that also do
 256  * strict type-checking.. See the
 257  * "unnecessary" pointer comparison.
 258  */
 259 #define min(x,y) ({ \
 260         typeof(x) _x = (x);     \
 261         typeof(y) _y = (y);     \
 262         (void) (&_x == &_y);            \
 263         _x < _y ? _x : _y; })
 264
 265 #define max(x,y) ({ \
 266         typeof(x) _x = (x);     \
 267         typeof(y) _y = (y);     \
 268         (void) (&_x == &_y);            \
 269         _x > _y ? _x : _y; })
 270
 271 /*
 272  * ..and if you can't take the strict
 273  * types, you can specify one yourself.
 274  *
 275  * Or not use min/max at all, of course.
 276  */
 277 #define min_t(type,x,y) \
 278         ({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
 279 #define max_t(type,x,y) \
 280         ({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 281
 282
 283 /**
 284  * container_of - cast a member of a structure out to the containing structure
 285  * @ptr:        the pointer to the member.
 286  * @type:       the type of the container struct this is embedded in.
 287  * @member:     the name of the member within the struct.
 288  *
 289  */
 290 #define container_of(ptr, type, member) ({                      \
 291         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 292         (type *)( (char *)__mptr - offsetof(type,member) );})
 293
 294 /*
 295  * Check at compile time that something is of a particular type.
 296  * Always evaluates to 1 so you may use it easily in comparisons.
 297  */
 298 #define typecheck(type,x) \
 299 ({      type __dummy; \
 300         typeof(x) __dummy2; \
 301         (void)(&__dummy == &__dummy2); \
 302         1; \
 303 })
 304
 305 /*
 306  * Check at compile time that 'function' is a certain type, or is a pointer
 307  * to that type (needs to use typedef for the function type.)
 308  */
 309 #define typecheck_fn(type,function) \
 310 ({      typeof(type) __tmp = function; \
 311         (void)__tmp; \
 312 })
 313
 314 #endif /* __KERNEL__ */
 315
 316 #define SI_LOAD_SHIFT   16
 317 struct sysinfo {
 318         long uptime;                    /* Seconds since boot */
 319         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 320         unsigned long totalram;         /* Total usable main memory size */
 321         unsigned long freeram;          /* Available memory size */
 322         unsigned long sharedram;        /* Amount of shared memory */
 323         unsigned long bufferram;        /* Memory used by buffers */
 324         unsigned long totalswap;        /* Total swap space size */
 325         unsigned long freeswap;         /* swap space still available */
 326         unsigned short procs;           /* Number of current processes */
 327         unsigned short pad;             /* explicit padding for m68k */
 328         unsigned long totalhigh;        /* Total high memory size */
 329         unsigned long freehigh;         /* Available high memory size */
 330         unsigned int mem_unit;          /* Memory unit size in bytes */
 331         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 332 };
 333
 334 /* Force a compilation error if condition is true */
 335 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 336
 337 /* Trap pasters of __FUNCTION__ at compile-time */
 338 #define __FUNCTION__ (__func__)
 339
 340 #endif