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 ALIGN(x,a)              __ALIGN_MASK(x,(typeof(x))(a)-1)
  34 #define __ALIGN_MASK(x,mask)    (((x)+(mask))&~(mask))
  35
  36 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
  37 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
  38 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
  39 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
  40
  41 #define KERN_EMERG      "<0>"   /* system is unusable                   */
  42 #define KERN_ALERT      "<1>"   /* action must be taken immediately     */
  43 #define KERN_CRIT       "<2>"   /* critical conditions                  */
  44 #define KERN_ERR        "<3>"   /* error conditions                     */
  45 #define KERN_WARNING    "<4>"   /* warning conditions                   */
  46 #define KERN_NOTICE     "<5>"   /* normal but significant condition     */
  47 #define KERN_INFO       "<6>"   /* informational                        */
  48 #define KERN_DEBUG      "<7>"   /* debug-level messages                 */
  49
  50 extern int console_printk[];
  51
  52 #define console_loglevel (console_printk[0])
  53 #define default_message_loglevel (console_printk[1])
  54 #define minimum_console_loglevel (console_printk[2])
  55 #define default_console_loglevel (console_printk[3])
  56
  57 struct completion;
  58 struct pt_regs;
  59 struct user;
  60
  61 /**
  62  * might_sleep - annotation for functions that can sleep
  63  *
  64  * this macro will print a stack trace if it is executed in an atomic
  65  * context (spinlock, irq-handler, ...).
  66  *
  67  * This is a useful debugging help to be able to catch problems early and not
  68  * be biten later when the calling function happens to sleep when it is not
  69  * supposed to.
  70  */
  71 #ifdef CONFIG_PREEMPT_VOLUNTARY
  72 extern int cond_resched(void);
  73 # define might_resched() cond_resched()
  74 #else
  75 # define might_resched() do { } while (0)
  76 #endif
  77
  78 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
  79   void __might_sleep(char *file, int line);
  80 # define might_sleep() \
  81         do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
  82 #else
  83 # define might_sleep() do { might_resched(); } while (0)
  84 #endif
  85
  86 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
  87
  88 #define abs(x) ({                               \
  89                 int __x = (x);                  \
  90                 (__x < 0) ? -__x : __x;         \
  91         })
  92
  93 #define labs(x) ({                              \
  94                 long __x = (x);                 \
  95                 (__x < 0) ? -__x : __x;         \
  96         })
  97
  98 extern struct atomic_notifier_head panic_notifier_list;
  99 extern long (*panic_blink)(long time);
 100 NORET_TYPE void panic(const char * fmt, ...)
 101         __attribute__ ((NORET_AND format (printf, 1, 2)));
 102 extern void oops_enter(void);
 103 extern void oops_exit(void);
 104 extern int oops_may_print(void);
 105 fastcall NORET_TYPE void do_exit(long error_code)
 106         ATTRIB_NORET;
 107 NORET_TYPE void complete_and_exit(struct completion *, long)
 108         ATTRIB_NORET;
 109 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 110 extern long simple_strtol(const char *,char **,unsigned int);
 111 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 112 extern long long simple_strtoll(const char *,char **,unsigned int);
 113 extern int sprintf(char * buf, const char * fmt, ...)
 114         __attribute__ ((format (printf, 2, 3)));
 115 extern int vsprintf(char *buf, const char *, va_list)
 116         __attribute__ ((format (printf, 2, 0)));
 117 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 118         __attribute__ ((format (printf, 3, 4)));
 119 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 120         __attribute__ ((format (printf, 3, 0)));
 121 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 122         __attribute__ ((format (printf, 3, 4)));
 123 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 124         __attribute__ ((format (printf, 3, 0)));
 125 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
 126         __attribute__ ((format (printf, 2, 3)));
 127
 128 extern int sscanf(const char *, const char *, ...)
 129         __attribute__ ((format (scanf, 2, 3)));
 130 extern int vsscanf(const char *, const char *, va_list)
 131         __attribute__ ((format (scanf, 2, 0)));
 132
 133 extern int get_option(char **str, int *pint);
 134 extern char *get_options(const char *str, int nints, int *ints);
 135 extern unsigned long long memparse(char *ptr, char **retptr);
 136
 137 extern int core_kernel_text(unsigned long addr);
 138 extern int __kernel_text_address(unsigned long addr);
 139 extern int kernel_text_address(unsigned long addr);
 140 extern int session_of_pgrp(int pgrp);
 141
 142 extern void dump_thread(struct pt_regs *regs, struct user *dump);
 143
 144 #ifdef CONFIG_PRINTK
 145 asmlinkage int vprintk(const char *fmt, va_list args)
 146         __attribute__ ((format (printf, 1, 0)));
 147 asmlinkage int printk(const char * fmt, ...)
 148         __attribute__ ((format (printf, 1, 2)));
 149 #else
 150 static inline int vprintk(const char *s, va_list args)
 151         __attribute__ ((format (printf, 1, 0)));
 152 static inline int vprintk(const char *s, va_list args) { return 0; }
 153 static inline int printk(const char *s, ...)
 154         __attribute__ ((format (printf, 1, 2)));
 155 static inline int printk(const char *s, ...) { return 0; }
 156 #endif
 157
 158 unsigned long int_sqrt(unsigned long);
 159
 160 static inline int __attribute_pure__ long_log2(unsigned long x)
 161 {
 162         int r = 0;
 163         for (x >>= 1; x > 0; x >>= 1)
 164                 r++;
 165         return r;
 166 }
 167
 168 static inline unsigned long
 169 __attribute_const__ roundup_pow_of_two(unsigned long x)
 170 {
 171         return 1UL << fls_long(x - 1);
 172 }
 173
 174 extern int printk_ratelimit(void);
 175 extern int __printk_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
 176 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 177                                 unsigned int interval_msec);
 178
 179 static inline void console_silent(void)
 180 {
 181         console_loglevel = 0;
 182 }
 183
 184 static inline void console_verbose(void)
 185 {
 186         if (console_loglevel)
 187                 console_loglevel = 15;
 188 }
 189
 190 extern void bust_spinlocks(int yes);
 191 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 192 extern int panic_timeout;
 193 extern int panic_on_oops;
 194 extern int panic_on_unrecovered_nmi;
 195 extern int tainted;
 196 extern const char *print_tainted(void);
 197 extern void add_taint(unsigned);
 198
 199 /* Values used for system_state */
 200 extern enum system_states {
 201         SYSTEM_BOOTING,
 202         SYSTEM_RUNNING,
 203         SYSTEM_HALT,
 204         SYSTEM_POWER_OFF,
 205         SYSTEM_RESTART,
 206         SYSTEM_SUSPEND_DISK,
 207 } system_state;
 208
 209 #define TAINT_PROPRIETARY_MODULE        (1<<0)
 210 #define TAINT_FORCED_MODULE             (1<<1)
 211 #define TAINT_UNSAFE_SMP                (1<<2)
 212 #define TAINT_FORCED_RMMOD              (1<<3)
 213 #define TAINT_MACHINE_CHECK             (1<<4)
 214 #define TAINT_BAD_PAGE                  (1<<5)
 215
 216 extern void dump_stack(void);
 217
 218 #ifdef DEBUG
 219 /* If you are writing a driver, please use dev_dbg instead */
 220 #define pr_debug(fmt,arg...) \
 221         printk(KERN_DEBUG fmt,##arg)
 222 #else
 223 static inline int __attribute__ ((format (printf, 1, 2))) pr_debug(const char * fmt, ...)
 224 {
 225         return 0;
 226 }
 227 #endif
 228
 229 #define pr_info(fmt,arg...) \
 230         printk(KERN_INFO fmt,##arg)
 231
 232 /*
 233  *      Display an IP address in readable format.
 234  */
 235
 236 #define NIPQUAD(addr) \
 237         ((unsigned char *)&addr)[0], \
 238         ((unsigned char *)&addr)[1], \
 239         ((unsigned char *)&addr)[2], \
 240         ((unsigned char *)&addr)[3]
 241 #define NIPQUAD_FMT "%u.%u.%u.%u"
 242
 243 #define NIP6(addr) \
 244         ntohs((addr).s6_addr16[0]), \
 245         ntohs((addr).s6_addr16[1]), \
 246         ntohs((addr).s6_addr16[2]), \
 247         ntohs((addr).s6_addr16[3]), \
 248         ntohs((addr).s6_addr16[4]), \
 249         ntohs((addr).s6_addr16[5]), \
 250         ntohs((addr).s6_addr16[6]), \
 251         ntohs((addr).s6_addr16[7])
 252 #define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 253 #define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
 254
 255 #if defined(__LITTLE_ENDIAN)
 256 #define HIPQUAD(addr) \
 257         ((unsigned char *)&addr)[3], \
 258         ((unsigned char *)&addr)[2], \
 259         ((unsigned char *)&addr)[1], \
 260         ((unsigned char *)&addr)[0]
 261 #elif defined(__BIG_ENDIAN)
 262 #define HIPQUAD NIPQUAD
 263 #else
 264 #error "Please fix asm/byteorder.h"
 265 #endif /* __LITTLE_ENDIAN */
 266
 267 /*
 268  * min()/max() macros that also do
 269  * strict type-checking.. See the
 270  * "unnecessary" pointer comparison.
 271  */
 272 #define min(x,y) ({ \
 273         typeof(x) _x = (x);     \
 274         typeof(y) _y = (y);     \
 275         (void) (&_x == &_y);            \
 276         _x < _y ? _x : _y; })
 277
 278 #define max(x,y) ({ \
 279         typeof(x) _x = (x);     \
 280         typeof(y) _y = (y);     \
 281         (void) (&_x == &_y);            \
 282         _x > _y ? _x : _y; })
 283
 284 /*
 285  * ..and if you can't take the strict
 286  * types, you can specify one yourself.
 287  *
 288  * Or not use min/max at all, of course.
 289  */
 290 #define min_t(type,x,y) \
 291         ({ type __x = (x); type __y = (y); __x < __y ? __x: __y; })
 292 #define max_t(type,x,y) \
 293         ({ type __x = (x); type __y = (y); __x > __y ? __x: __y; })
 294
 295
 296 /**
 297  * container_of - cast a member of a structure out to the containing structure
 298  * @ptr:        the pointer to the member.
 299  * @type:       the type of the container struct this is embedded in.
 300  * @member:     the name of the member within the struct.
 301  *
 302  */
 303 #define container_of(ptr, type, member) ({                      \
 304         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 305         (type *)( (char *)__mptr - offsetof(type,member) );})
 306
 307 /*
 308  * Check at compile time that something is of a particular type.
 309  * Always evaluates to 1 so you may use it easily in comparisons.
 310  */
 311 #define typecheck(type,x) \
 312 ({      type __dummy; \
 313         typeof(x) __dummy2; \
 314         (void)(&__dummy == &__dummy2); \
 315         1; \
 316 })
 317
 318 /*
 319  * Check at compile time that 'function' is a certain type, or is a pointer
 320  * to that type (needs to use typedef for the function type.)
 321  */
 322 #define typecheck_fn(type,function) \
 323 ({      typeof(type) __tmp = function; \
 324         (void)__tmp; \
 325 })
 326
 327 #endif /* __KERNEL__ */
 328
 329 #define SI_LOAD_SHIFT   16
 330 struct sysinfo {
 331         long uptime;                    /* Seconds since boot */
 332         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 333         unsigned long totalram;         /* Total usable main memory size */
 334         unsigned long freeram;          /* Available memory size */
 335         unsigned long sharedram;        /* Amount of shared memory */
 336         unsigned long bufferram;        /* Memory used by buffers */
 337         unsigned long totalswap;        /* Total swap space size */
 338         unsigned long freeswap;         /* swap space still available */
 339         unsigned short procs;           /* Number of current processes */
 340         unsigned short pad;             /* explicit padding for m68k */
 341         unsigned long totalhigh;        /* Total high memory size */
 342         unsigned long freehigh;         /* Available high memory size */
 343         unsigned int mem_unit;          /* Memory unit size in bytes */
 344         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 345 };
 346
 347 /* Force a compilation error if condition is true */
 348 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 349
 350 /* Force a compilation error if condition is true, but also produce a
 351    result (of value 0 and type size_t), so the expression can be used
 352    e.g. in a structure initializer (or where-ever else comma expressions
 353    aren't permitted). */
 354 #define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
 355
 356 /* Trap pasters of __FUNCTION__ at compile-time */
 357 #define __FUNCTION__ (__func__)
 358
 359 /* This helps us to avoid #ifdef CONFIG_NUMA */
 360 #ifdef CONFIG_NUMA
 361 #define NUMA_BUILD 1
 362 #else
 363 #define NUMA_BUILD 0
 364 #endif
 365
 366 #endif