linux/include/linux/kernel.h
<<
>>
Prefs
   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 <linux/log2.h>
  17#include <linux/typecheck.h>
  18#include <linux/ratelimit.h>
  19#include <linux/dynamic_printk.h>
  20#include <asm/byteorder.h>
  21#include <asm/bug.h>
  22
  23extern const char linux_banner[];
  24extern const char linux_proc_banner[];
  25
  26#define USHORT_MAX      ((u16)(~0U))
  27#define SHORT_MAX       ((s16)(USHORT_MAX>>1))
  28#define SHORT_MIN       (-SHORT_MAX - 1)
  29#define INT_MAX         ((int)(~0U>>1))
  30#define INT_MIN         (-INT_MAX - 1)
  31#define UINT_MAX        (~0U)
  32#define LONG_MAX        ((long)(~0UL>>1))
  33#define LONG_MIN        (-LONG_MAX - 1)
  34#define ULONG_MAX       (~0UL)
  35#define LLONG_MAX       ((long long)(~0ULL>>1))
  36#define LLONG_MIN       (-LLONG_MAX - 1)
  37#define ULLONG_MAX      (~0ULL)
  38
  39#define STACK_MAGIC     0xdeadbeef
  40
  41#define ALIGN(x,a)              __ALIGN_MASK(x,(typeof(x))(a)-1)
  42#define __ALIGN_MASK(x,mask)    (((x)+(mask))&~(mask))
  43#define PTR_ALIGN(p, a)         ((typeof(p))ALIGN((unsigned long)(p), (a)))
  44#define IS_ALIGNED(x, a)                (((x) & ((typeof(x))(a) - 1)) == 0)
  45
  46#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
  47
  48#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
  49#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
  50#define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
  51
  52#define _RET_IP_                (unsigned long)__builtin_return_address(0)
  53#define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
  54
  55#ifdef CONFIG_LBD
  56# include <asm/div64.h>
  57# define sector_div(a, b) do_div(a, b)
  58#else
  59# define sector_div(n, b)( \
  60{ \
  61        int _res; \
  62        _res = (n) % (b); \
  63        (n) /= (b); \
  64        _res; \
  65} \
  66)
  67#endif
  68
  69/**
  70 * upper_32_bits - return bits 32-63 of a number
  71 * @n: the number we're accessing
  72 *
  73 * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
  74 * the "right shift count >= width of type" warning when that quantity is
  75 * 32-bits.
  76 */
  77#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
  78
  79/**
  80 * lower_32_bits - return bits 0-31 of a number
  81 * @n: the number we're accessing
  82 */
  83#define lower_32_bits(n) ((u32)(n))
  84
  85#define KERN_EMERG      "<0>"   /* system is unusable                   */
  86#define KERN_ALERT      "<1>"   /* action must be taken immediately     */
  87#define KERN_CRIT       "<2>"   /* critical conditions                  */
  88#define KERN_ERR        "<3>"   /* error conditions                     */
  89#define KERN_WARNING    "<4>"   /* warning conditions                   */
  90#define KERN_NOTICE     "<5>"   /* normal but significant condition     */
  91#define KERN_INFO       "<6>"   /* informational                        */
  92#define KERN_DEBUG      "<7>"   /* debug-level messages                 */
  93
  94/*
  95 * Annotation for a "continued" line of log printout (only done after a
  96 * line that had no enclosing \n). Only to be used by core/arch code
  97 * during early bootup (a continued line is not SMP-safe otherwise).
  98 */
  99#define KERN_CONT       ""
 100
 101extern int console_printk[];
 102
 103#define console_loglevel (console_printk[0])
 104#define default_message_loglevel (console_printk[1])
 105#define minimum_console_loglevel (console_printk[2])
 106#define default_console_loglevel (console_printk[3])
 107
 108struct completion;
 109struct pt_regs;
 110struct user;
 111
 112#ifdef CONFIG_PREEMPT_VOLUNTARY
 113extern int _cond_resched(void);
 114# define might_resched() _cond_resched()
 115#else
 116# define might_resched() do { } while (0)
 117#endif
 118
 119#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
 120  void __might_sleep(char *file, int line);
 121/**
 122 * might_sleep - annotation for functions that can sleep
 123 *
 124 * this macro will print a stack trace if it is executed in an atomic
 125 * context (spinlock, irq-handler, ...).
 126 *
 127 * This is a useful debugging help to be able to catch problems early and not
 128 * be bitten later when the calling function happens to sleep when it is not
 129 * supposed to.
 130 */
 131# define might_sleep() \
 132        do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
 133#else
 134# define might_sleep() do { might_resched(); } while (0)
 135#endif
 136
 137#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
 138
 139#define abs(x) ({                               \
 140                int __x = (x);                  \
 141                (__x < 0) ? -__x : __x;         \
 142        })
 143
 144extern struct atomic_notifier_head panic_notifier_list;
 145extern long (*panic_blink)(long time);
 146NORET_TYPE void panic(const char * fmt, ...)
 147        __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
 148extern void oops_enter(void);
 149extern void oops_exit(void);
 150extern int oops_may_print(void);
 151NORET_TYPE void do_exit(long error_code)
 152        ATTRIB_NORET;
 153NORET_TYPE void complete_and_exit(struct completion *, long)
 154        ATTRIB_NORET;
 155extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 156extern long simple_strtol(const char *,char **,unsigned int);
 157extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 158extern long long simple_strtoll(const char *,char **,unsigned int);
 159extern int strict_strtoul(const char *, unsigned int, unsigned long *);
 160extern int strict_strtol(const char *, unsigned int, long *);
 161extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
 162extern int strict_strtoll(const char *, unsigned int, long long *);
 163extern int sprintf(char * buf, const char * fmt, ...)
 164        __attribute__ ((format (printf, 2, 3)));
 165extern int vsprintf(char *buf, const char *, va_list)
 166        __attribute__ ((format (printf, 2, 0)));
 167extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 168        __attribute__ ((format (printf, 3, 4)));
 169extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 170        __attribute__ ((format (printf, 3, 0)));
 171extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 172        __attribute__ ((format (printf, 3, 4)));
 173extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 174        __attribute__ ((format (printf, 3, 0)));
 175extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
 176        __attribute__ ((format (printf, 2, 3)));
 177extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
 178
 179extern int sscanf(const char *, const char *, ...)
 180        __attribute__ ((format (scanf, 2, 3)));
 181extern int vsscanf(const char *, const char *, va_list)
 182        __attribute__ ((format (scanf, 2, 0)));
 183
 184extern int get_option(char **str, int *pint);
 185extern char *get_options(const char *str, int nints, int *ints);
 186extern unsigned long long memparse(const char *ptr, char **retptr);
 187
 188extern int core_kernel_text(unsigned long addr);
 189extern int __kernel_text_address(unsigned long addr);
 190extern int kernel_text_address(unsigned long addr);
 191struct pid;
 192extern struct pid *session_of_pgrp(struct pid *pgrp);
 193
 194/*
 195 * FW_BUG
 196 * Add this to a message where you are sure the firmware is buggy or behaves
 197 * really stupid or out of spec. Be aware that the responsible BIOS developer
 198 * should be able to fix this issue or at least get a concrete idea of the
 199 * problem by reading your message without the need of looking at the kernel
 200 * code.
 201 * 
 202 * Use it for definite and high priority BIOS bugs.
 203 *
 204 * FW_WARN
 205 * Use it for not that clear (e.g. could the kernel messed up things already?)
 206 * and medium priority BIOS bugs.
 207 *
 208 * FW_INFO
 209 * Use this one if you want to tell the user or vendor about something
 210 * suspicious, but generally harmless related to the firmware.
 211 *
 212 * Use it for information or very low priority BIOS bugs.
 213 */
 214#define FW_BUG          "[Firmware Bug]: "
 215#define FW_WARN         "[Firmware Warn]: "
 216#define FW_INFO         "[Firmware Info]: "
 217
 218#ifdef CONFIG_PRINTK
 219asmlinkage int vprintk(const char *fmt, va_list args)
 220        __attribute__ ((format (printf, 1, 0)));
 221asmlinkage int printk(const char * fmt, ...)
 222        __attribute__ ((format (printf, 1, 2))) __cold;
 223
 224extern struct ratelimit_state printk_ratelimit_state;
 225extern int printk_ratelimit(void);
 226extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 227                                   unsigned int interval_msec);
 228#else
 229static inline int vprintk(const char *s, va_list args)
 230        __attribute__ ((format (printf, 1, 0)));
 231static inline int vprintk(const char *s, va_list args) { return 0; }
 232static inline int printk(const char *s, ...)
 233        __attribute__ ((format (printf, 1, 2)));
 234static inline int __cold printk(const char *s, ...) { return 0; }
 235static inline int printk_ratelimit(void) { return 0; }
 236static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
 237                                          unsigned int interval_msec)   \
 238                { return false; }
 239#endif
 240
 241extern int printk_needs_cpu(int cpu);
 242extern void printk_tick(void);
 243
 244extern void asmlinkage __attribute__((format(printf, 1, 2)))
 245        early_printk(const char *fmt, ...);
 246
 247unsigned long int_sqrt(unsigned long);
 248
 249static inline void console_silent(void)
 250{
 251        console_loglevel = 0;
 252}
 253
 254static inline void console_verbose(void)
 255{
 256        if (console_loglevel)
 257                console_loglevel = 15;
 258}
 259
 260extern void bust_spinlocks(int yes);
 261extern void wake_up_klogd(void);
 262extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 263extern int panic_timeout;
 264extern int panic_on_oops;
 265extern int panic_on_unrecovered_nmi;
 266extern const char *print_tainted(void);
 267extern void add_taint(unsigned flag);
 268extern int test_taint(unsigned flag);
 269extern unsigned long get_taint(void);
 270extern int root_mountflags;
 271
 272/* Values used for system_state */
 273extern enum system_states {
 274        SYSTEM_BOOTING,
 275        SYSTEM_RUNNING,
 276        SYSTEM_HALT,
 277        SYSTEM_POWER_OFF,
 278        SYSTEM_RESTART,
 279        SYSTEM_SUSPEND_DISK,
 280} system_state;
 281
 282#define TAINT_PROPRIETARY_MODULE        0
 283#define TAINT_FORCED_MODULE             1
 284#define TAINT_UNSAFE_SMP                2
 285#define TAINT_FORCED_RMMOD              3
 286#define TAINT_MACHINE_CHECK             4
 287#define TAINT_BAD_PAGE                  5
 288#define TAINT_USER                      6
 289#define TAINT_DIE                       7
 290#define TAINT_OVERRIDDEN_ACPI_TABLE     8
 291#define TAINT_WARN                      9
 292#define TAINT_CRAP                      10
 293
 294extern void dump_stack(void) __cold;
 295
 296enum {
 297        DUMP_PREFIX_NONE,
 298        DUMP_PREFIX_ADDRESS,
 299        DUMP_PREFIX_OFFSET
 300};
 301extern void hex_dump_to_buffer(const void *buf, size_t len,
 302                                int rowsize, int groupsize,
 303                                char *linebuf, size_t linebuflen, bool ascii);
 304extern void print_hex_dump(const char *level, const char *prefix_str,
 305                                int prefix_type, int rowsize, int groupsize,
 306                                const void *buf, size_t len, bool ascii);
 307extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 308                        const void *buf, size_t len);
 309
 310extern const char hex_asc[];
 311#define hex_asc_lo(x)   hex_asc[((x) & 0x0f)]
 312#define hex_asc_hi(x)   hex_asc[((x) & 0xf0) >> 4]
 313
 314static inline char *pack_hex_byte(char *buf, u8 byte)
 315{
 316        *buf++ = hex_asc_hi(byte);
 317        *buf++ = hex_asc_lo(byte);
 318        return buf;
 319}
 320
 321#ifndef pr_fmt
 322#define pr_fmt(fmt) fmt
 323#endif
 324
 325#define pr_emerg(fmt, ...) \
 326        printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 327#define pr_alert(fmt, ...) \
 328        printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 329#define pr_crit(fmt, ...) \
 330        printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 331#define pr_err(fmt, ...) \
 332        printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 333#define pr_warning(fmt, ...) \
 334        printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 335#define pr_notice(fmt, ...) \
 336        printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 337#define pr_info(fmt, ...) \
 338        printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 339
 340/* If you are writing a driver, please use dev_dbg instead */
 341#if defined(CONFIG_DYNAMIC_PRINTK_DEBUG)
 342#define pr_debug(fmt, ...) do { \
 343        dynamic_pr_debug(pr_fmt(fmt), ##__VA_ARGS__); \
 344        } while (0)
 345#elif defined(DEBUG)
 346#define pr_debug(fmt, ...) \
 347        printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 348#else
 349#define pr_debug(fmt, ...) \
 350        ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
 351#endif
 352
 353/*
 354 *      Display an IP address in readable format.
 355 */
 356
 357#define NIPQUAD(addr) \
 358        ((unsigned char *)&addr)[0], \
 359        ((unsigned char *)&addr)[1], \
 360        ((unsigned char *)&addr)[2], \
 361        ((unsigned char *)&addr)[3]
 362#define NIPQUAD_FMT "%u.%u.%u.%u"
 363
 364#define NIP6(addr) \
 365        ntohs((addr).s6_addr16[0]), \
 366        ntohs((addr).s6_addr16[1]), \
 367        ntohs((addr).s6_addr16[2]), \
 368        ntohs((addr).s6_addr16[3]), \
 369        ntohs((addr).s6_addr16[4]), \
 370        ntohs((addr).s6_addr16[5]), \
 371        ntohs((addr).s6_addr16[6]), \
 372        ntohs((addr).s6_addr16[7])
 373#define NIP6_FMT "%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x"
 374#define NIP6_SEQFMT "%04x%04x%04x%04x%04x%04x%04x%04x"
 375
 376#if defined(__LITTLE_ENDIAN)
 377#define HIPQUAD(addr) \
 378        ((unsigned char *)&addr)[3], \
 379        ((unsigned char *)&addr)[2], \
 380        ((unsigned char *)&addr)[1], \
 381        ((unsigned char *)&addr)[0]
 382#elif defined(__BIG_ENDIAN)
 383#define HIPQUAD NIPQUAD
 384#else
 385#error "Please fix asm/byteorder.h"
 386#endif /* __LITTLE_ENDIAN */
 387
 388/*
 389 * min()/max()/clamp() macros that also do
 390 * strict type-checking.. See the
 391 * "unnecessary" pointer comparison.
 392 */
 393#define min(x, y) ({                            \
 394        typeof(x) _min1 = (x);                  \
 395        typeof(y) _min2 = (y);                  \
 396        (void) (&_min1 == &_min2);              \
 397        _min1 < _min2 ? _min1 : _min2; })
 398
 399#define max(x, y) ({                            \
 400        typeof(x) _max1 = (x);                  \
 401        typeof(y) _max2 = (y);                  \
 402        (void) (&_max1 == &_max2);              \
 403        _max1 > _max2 ? _max1 : _max2; })
 404
 405/**
 406 * clamp - return a value clamped to a given range with strict typechecking
 407 * @val: current value
 408 * @min: minimum allowable value
 409 * @max: maximum allowable value
 410 *
 411 * This macro does strict typechecking of min/max to make sure they are of the
 412 * same type as val.  See the unnecessary pointer comparisons.
 413 */
 414#define clamp(val, min, max) ({                 \
 415        typeof(val) __val = (val);              \
 416        typeof(min) __min = (min);              \
 417        typeof(max) __max = (max);              \
 418        (void) (&__val == &__min);              \
 419        (void) (&__val == &__max);              \
 420        __val = __val < __min ? __min: __val;   \
 421        __val > __max ? __max: __val; })
 422
 423/*
 424 * ..and if you can't take the strict
 425 * types, you can specify one yourself.
 426 *
 427 * Or not use min/max/clamp at all, of course.
 428 */
 429#define min_t(type, x, y) ({                    \
 430        type __min1 = (x);                      \
 431        type __min2 = (y);                      \
 432        __min1 < __min2 ? __min1: __min2; })
 433
 434#define max_t(type, x, y) ({                    \
 435        type __max1 = (x);                      \
 436        type __max2 = (y);                      \
 437        __max1 > __max2 ? __max1: __max2; })
 438
 439/**
 440 * clamp_t - return a value clamped to a given range using a given type
 441 * @type: the type of variable to use
 442 * @val: current value
 443 * @min: minimum allowable value
 444 * @max: maximum allowable value
 445 *
 446 * This macro does no typechecking and uses temporary variables of type
 447 * 'type' to make all the comparisons.
 448 */
 449#define clamp_t(type, val, min, max) ({         \
 450        type __val = (val);                     \
 451        type __min = (min);                     \
 452        type __max = (max);                     \
 453        __val = __val < __min ? __min: __val;   \
 454        __val > __max ? __max: __val; })
 455
 456/**
 457 * clamp_val - return a value clamped to a given range using val's type
 458 * @val: current value
 459 * @min: minimum allowable value
 460 * @max: maximum allowable value
 461 *
 462 * This macro does no typechecking and uses temporary variables of whatever
 463 * type the input argument 'val' is.  This is useful when val is an unsigned
 464 * type and min and max are literals that will otherwise be assigned a signed
 465 * integer type.
 466 */
 467#define clamp_val(val, min, max) ({             \
 468        typeof(val) __val = (val);              \
 469        typeof(val) __min = (min);              \
 470        typeof(val) __max = (max);              \
 471        __val = __val < __min ? __min: __val;   \
 472        __val > __max ? __max: __val; })
 473
 474/**
 475 * container_of - cast a member of a structure out to the containing structure
 476 * @ptr:        the pointer to the member.
 477 * @type:       the type of the container struct this is embedded in.
 478 * @member:     the name of the member within the struct.
 479 *
 480 */
 481#define container_of(ptr, type, member) ({                      \
 482        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 483        (type *)( (char *)__mptr - offsetof(type,member) );})
 484
 485struct sysinfo;
 486extern int do_sysinfo(struct sysinfo *info);
 487
 488#endif /* __KERNEL__ */
 489
 490#define SI_LOAD_SHIFT   16
 491struct sysinfo {
 492        long uptime;                    /* Seconds since boot */
 493        unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 494        unsigned long totalram;         /* Total usable main memory size */
 495        unsigned long freeram;          /* Available memory size */
 496        unsigned long sharedram;        /* Amount of shared memory */
 497        unsigned long bufferram;        /* Memory used by buffers */
 498        unsigned long totalswap;        /* Total swap space size */
 499        unsigned long freeswap;         /* swap space still available */
 500        unsigned short procs;           /* Number of current processes */
 501        unsigned short pad;             /* explicit padding for m68k */
 502        unsigned long totalhigh;        /* Total high memory size */
 503        unsigned long freehigh;         /* Available high memory size */
 504        unsigned int mem_unit;          /* Memory unit size in bytes */
 505        char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 506};
 507
 508/* Force a compilation error if condition is true */
 509#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 510
 511/* Force a compilation error if condition is true, but also produce a
 512   result (of value 0 and type size_t), so the expression can be used
 513   e.g. in a structure initializer (or where-ever else comma expressions
 514   aren't permitted). */
 515#define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
 516
 517/* Trap pasters of __FUNCTION__ at compile-time */
 518#define __FUNCTION__ (__func__)
 519
 520/* This helps us to avoid #ifdef CONFIG_NUMA */
 521#ifdef CONFIG_NUMA
 522#define NUMA_BUILD 1
 523#else
 524#define NUMA_BUILD 0
 525#endif
 526
 527/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
 528#ifdef CONFIG_FTRACE_MCOUNT_RECORD
 529# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
 530#endif
 531
 532#endif
 533
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.