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 <linux/log2.h>
  17 #include <linux/typecheck.h>
  18 #include <linux/ratelimit.h>
  19 #include <linux/dynamic_debug.h>
  20 #include <asm/byteorder.h>
  21 #include <asm/bug.h>
  22
  23 extern const char linux_banner[];
  24 extern 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 #define DIV_ROUND_CLOSEST(x, divisor)(                  \
  52 {                                                       \
  53         typeof(divisor) __divisor = divisor;            \
  54         (((x) + ((__divisor) / 2)) / (__divisor));      \
  55 }                                                       \
  56 )
  57
  58 /*
  59  * Multiplies an integer by a fraction, while avoiding unnecessary
  60  * overflow or loss of precision.
  61  */
  62 #define mult_frac(x, numer, denom)(                     \
  63 {                                                       \
  64         typeof(x) quot = (x) / (denom);                 \
  65         typeof(x) rem  = (x) % (denom);                 \
  66         (quot * (numer)) + ((rem * (numer)) / (denom)); \
  67 }                                                       \
  68 )
  69
  70
  71 #define _RET_IP_                (unsigned long)__builtin_return_address(0)
  72 #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
  73
  74 #ifdef CONFIG_LBDAF
  75 # include <asm/div64.h>
  76 # define sector_div(a, b) do_div(a, b)
  77 #else
  78 # define sector_div(n, b)( \
  79 { \
  80         int _res; \
  81         _res = (n) % (b); \
  82         (n) /= (b); \
  83         _res; \
  84 } \
  85 )
  86 #endif
  87
  88 /**
  89  * upper_32_bits - return bits 32-63 of a number
  90  * @n: the number we're accessing
  91  *
  92  * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
  93  * the "right shift count >= width of type" warning when that quantity is
  94  * 32-bits.
  95  */
  96 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
  97
  98 /**
  99  * lower_32_bits - return bits 0-31 of a number
 100  * @n: the number we're accessing
 101  */
 102 #define lower_32_bits(n) ((u32)(n))
 103
 104 #define KERN_EMERG      "<0>"   /* system is unusable                   */
 105 #define KERN_ALERT      "<1>"   /* action must be taken immediately     */
 106 #define KERN_CRIT       "<2>"   /* critical conditions                  */
 107 #define KERN_ERR        "<3>"   /* error conditions                     */
 108 #define KERN_WARNING    "<4>"   /* warning conditions                   */
 109 #define KERN_NOTICE     "<5>"   /* normal but significant condition     */
 110 #define KERN_INFO       "<6>"   /* informational                        */
 111 #define KERN_DEBUG      "<7>"   /* debug-level messages                 */
 112
 113 /* Use the default kernel loglevel */
 114 #define KERN_DEFAULT    "<d>"
 115 /*
 116  * Annotation for a "continued" line of log printout (only done after a
 117  * line that had no enclosing \n). Only to be used by core/arch code
 118  * during early bootup (a continued line is not SMP-safe otherwise).
 119  */
 120 #define KERN_CONT       "<c>"
 121
 122 extern int console_printk[];
 123
 124 #define console_loglevel (console_printk[0])
 125 #define default_message_loglevel (console_printk[1])
 126 #define minimum_console_loglevel (console_printk[2])
 127 #define default_console_loglevel (console_printk[3])
 128
 129 struct completion;
 130 struct pt_regs;
 131 struct user;
 132
 133 #ifdef CONFIG_PREEMPT_VOLUNTARY
 134 extern int _cond_resched(void);
 135 # define might_resched() _cond_resched()
 136 #else
 137 # define might_resched() do { } while (0)
 138 #endif
 139
 140 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
 141   void __might_sleep(char *file, int line, int preempt_offset);
 142 /**
 143  * might_sleep - annotation for functions that can sleep
 144  *
 145  * this macro will print a stack trace if it is executed in an atomic
 146  * context (spinlock, irq-handler, ...).
 147  *
 148  * This is a useful debugging help to be able to catch problems early and not
 149  * be bitten later when the calling function happens to sleep when it is not
 150  * supposed to.
 151  */
 152 # define might_sleep() \
 153         do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
 154 #else
 155   static inline void __might_sleep(char *file, int line, int preempt_offset) { }
 156 # define might_sleep() do { might_resched(); } while (0)
 157 #endif
 158
 159 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
 160
 161 #define abs(x) ({                               \
 162                 long __x = (x);                 \
 163                 (__x < 0) ? -__x : __x;         \
 164         })
 165
 166 #ifdef CONFIG_PROVE_LOCKING
 167 void might_fault(void);
 168 #else
 169 static inline void might_fault(void)
 170 {
 171         might_sleep();
 172 }
 173 #endif
 174
 175 extern struct atomic_notifier_head panic_notifier_list;
 176 extern long (*panic_blink)(long time);
 177 NORET_TYPE void panic(const char * fmt, ...)
 178         __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
 179 extern void oops_enter(void);
 180 extern void oops_exit(void);
 181 extern int oops_may_print(void);
 182 NORET_TYPE void do_exit(long error_code)
 183         ATTRIB_NORET;
 184 NORET_TYPE void complete_and_exit(struct completion *, long)
 185         ATTRIB_NORET;
 186 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 187 extern long simple_strtol(const char *,char **,unsigned int);
 188 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 189 extern long long simple_strtoll(const char *,char **,unsigned int);
 190 extern int strict_strtoul(const char *, unsigned int, unsigned long *);
 191 extern int strict_strtol(const char *, unsigned int, long *);
 192 extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
 193 extern int strict_strtoll(const char *, unsigned int, long long *);
 194 extern int sprintf(char * buf, const char * fmt, ...)
 195         __attribute__ ((format (printf, 2, 3)));
 196 extern int vsprintf(char *buf, const char *, va_list)
 197         __attribute__ ((format (printf, 2, 0)));
 198 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 199         __attribute__ ((format (printf, 3, 4)));
 200 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 201         __attribute__ ((format (printf, 3, 0)));
 202 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 203         __attribute__ ((format (printf, 3, 4)));
 204 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 205         __attribute__ ((format (printf, 3, 0)));
 206 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
 207         __attribute__ ((format (printf, 2, 3)));
 208 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
 209
 210 extern int sscanf(const char *, const char *, ...)
 211         __attribute__ ((format (scanf, 2, 3)));
 212 extern int vsscanf(const char *, const char *, va_list)
 213         __attribute__ ((format (scanf, 2, 0)));
 214
 215 extern int get_option(char **str, int *pint);
 216 extern char *get_options(const char *str, int nints, int *ints);
 217 extern unsigned long long memparse(const char *ptr, char **retptr);
 218
 219 extern int core_kernel_text(unsigned long addr);
 220 extern int __kernel_text_address(unsigned long addr);
 221 extern int kernel_text_address(unsigned long addr);
 222 extern int func_ptr_is_kernel_text(void *ptr);
 223
 224 struct pid;
 225 extern struct pid *session_of_pgrp(struct pid *pgrp);
 226
 227 /*
 228  * FW_BUG
 229  * Add this to a message where you are sure the firmware is buggy or behaves
 230  * really stupid or out of spec. Be aware that the responsible BIOS developer
 231  * should be able to fix this issue or at least get a concrete idea of the
 232  * problem by reading your message without the need of looking at the kernel
 233  * code.
 234  *
 235  * Use it for definite and high priority BIOS bugs.
 236  *
 237  * FW_WARN
 238  * Use it for not that clear (e.g. could the kernel messed up things already?)
 239  * and medium priority BIOS bugs.
 240  *
 241  * FW_INFO
 242  * Use this one if you want to tell the user or vendor about something
 243  * suspicious, but generally harmless related to the firmware.
 244  *
 245  * Use it for information or very low priority BIOS bugs.
 246  */
 247 #define FW_BUG          "[Firmware Bug]: "
 248 #define FW_WARN         "[Firmware Warn]: "
 249 #define FW_INFO         "[Firmware Info]: "
 250
 251 #ifdef CONFIG_PRINTK
 252 asmlinkage int vprintk(const char *fmt, va_list args)
 253         __attribute__ ((format (printf, 1, 0)));
 254 asmlinkage int printk(const char * fmt, ...)
 255         __attribute__ ((format (printf, 1, 2))) __cold;
 256
 257 extern struct ratelimit_state printk_ratelimit_state;
 258 extern int printk_ratelimit(void);
 259 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 260                                    unsigned int interval_msec);
 261
 262 extern int printk_delay_msec;
 263
 264 /*
 265  * Print a one-time message (analogous to WARN_ONCE() et al):
 266  */
 267 #define printk_once(x...) ({                    \
 268         static bool __print_once = true;        \
 269                                                 \
 270         if (__print_once) {                     \
 271                 __print_once = false;           \
 272                 printk(x);                      \
 273         }                                       \
 274 })
 275
 276 void log_buf_kexec_setup(void);
 277 #else
 278 static inline int vprintk(const char *s, va_list args)
 279         __attribute__ ((format (printf, 1, 0)));
 280 static inline int vprintk(const char *s, va_list args) { return 0; }
 281 static inline int printk(const char *s, ...)
 282         __attribute__ ((format (printf, 1, 2)));
 283 static inline int __cold printk(const char *s, ...) { return 0; }
 284 static inline int printk_ratelimit(void) { return 0; }
 285 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
 286                                           unsigned int interval_msec)   \
 287                 { return false; }
 288
 289 /* No effect, but we still get type checking even in the !PRINTK case: */
 290 #define printk_once(x...) printk(x)
 291
 292 static inline void log_buf_kexec_setup(void)
 293 {
 294 }
 295 #endif
 296
 297 extern int printk_needs_cpu(int cpu);
 298 extern void printk_tick(void);
 299
 300 extern void asmlinkage __attribute__((format(printf, 1, 2)))
 301         early_printk(const char *fmt, ...);
 302
 303 unsigned long int_sqrt(unsigned long);
 304
 305 static inline void console_silent(void)
 306 {
 307         console_loglevel = 0;
 308 }
 309
 310 static inline void console_verbose(void)
 311 {
 312         if (console_loglevel)
 313                 console_loglevel = 15;
 314 }
 315
 316 extern void bust_spinlocks(int yes);
 317 extern void wake_up_klogd(void);
 318 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 319 extern int panic_timeout;
 320 extern int panic_on_oops;
 321 extern int panic_on_unrecovered_nmi;
 322 extern int panic_on_io_nmi;
 323 extern const char *print_tainted(void);
 324 extern void add_taint(unsigned flag);
 325 extern int test_taint(unsigned flag);
 326 extern unsigned long get_taint(void);
 327 extern int root_mountflags;
 328
 329 /* Values used for system_state */
 330 extern enum system_states {
 331         SYSTEM_BOOTING,
 332         SYSTEM_RUNNING,
 333         SYSTEM_HALT,
 334         SYSTEM_POWER_OFF,
 335         SYSTEM_RESTART,
 336         SYSTEM_SUSPEND_DISK,
 337 } system_state;
 338
 339 #define TAINT_PROPRIETARY_MODULE        0
 340 #define TAINT_FORCED_MODULE             1
 341 #define TAINT_UNSAFE_SMP                2
 342 #define TAINT_FORCED_RMMOD              3
 343 #define TAINT_MACHINE_CHECK             4
 344 #define TAINT_BAD_PAGE                  5
 345 #define TAINT_USER                      6
 346 #define TAINT_DIE                       7
 347 #define TAINT_OVERRIDDEN_ACPI_TABLE     8
 348 #define TAINT_WARN                      9
 349 #define TAINT_CRAP                      10
 350
 351 extern void dump_stack(void) __cold;
 352
 353 enum {
 354         DUMP_PREFIX_NONE,
 355         DUMP_PREFIX_ADDRESS,
 356         DUMP_PREFIX_OFFSET
 357 };
 358 extern void hex_dump_to_buffer(const void *buf, size_t len,
 359                                 int rowsize, int groupsize,
 360                                 char *linebuf, size_t linebuflen, bool ascii);
 361 extern void print_hex_dump(const char *level, const char *prefix_str,
 362                                 int prefix_type, int rowsize, int groupsize,
 363                                 const void *buf, size_t len, bool ascii);
 364 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 365                         const void *buf, size_t len);
 366
 367 extern const char hex_asc[];
 368 #define hex_asc_lo(x)   hex_asc[((x) & 0x0f)]
 369 #define hex_asc_hi(x)   hex_asc[((x) & 0xf0) >> 4]
 370
 371 static inline char *pack_hex_byte(char *buf, u8 byte)
 372 {
 373         *buf++ = hex_asc_hi(byte);
 374         *buf++ = hex_asc_lo(byte);
 375         return buf;
 376 }
 377
 378 #ifndef pr_fmt
 379 #define pr_fmt(fmt) fmt
 380 #endif
 381
 382 #define pr_emerg(fmt, ...) \
 383         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 384 #define pr_alert(fmt, ...) \
 385         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 386 #define pr_crit(fmt, ...) \
 387         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 388 #define pr_err(fmt, ...) \
 389         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 390 #define pr_warning(fmt, ...) \
 391         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 392 #define pr_notice(fmt, ...) \
 393         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 394 #define pr_info(fmt, ...) \
 395         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 396 #define pr_cont(fmt, ...) \
 397         printk(KERN_CONT fmt, ##__VA_ARGS__)
 398
 399 /* pr_devel() should produce zero code unless DEBUG is defined */
 400 #ifdef DEBUG
 401 #define pr_devel(fmt, ...) \
 402         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 403 #else
 404 #define pr_devel(fmt, ...) \
 405         ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
 406 #endif
 407
 408 /* If you are writing a driver, please use dev_dbg instead */
 409 #if defined(DEBUG)
 410 #define pr_debug(fmt, ...) \
 411         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 412 #elif defined(CONFIG_DYNAMIC_DEBUG)
 413 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
 414 #define pr_debug(fmt, ...) do { \
 415         dynamic_pr_debug(fmt, ##__VA_ARGS__); \
 416         } while (0)
 417 #else
 418 #define pr_debug(fmt, ...) \
 419         ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
 420 #endif
 421
 422 /*
 423  * ratelimited messages with local ratelimit_state,
 424  * no local ratelimit_state used in the !PRINTK case
 425  */
 426 #ifdef CONFIG_PRINTK
 427 #define printk_ratelimited(fmt, ...)  ({                                \
 428         static DEFINE_RATELIMIT_STATE(_rs,                              \
 429                                       DEFAULT_RATELIMIT_INTERVAL,       \
 430                                       DEFAULT_RATELIMIT_BURST);         \
 431                                                                         \
 432         if (__ratelimit(&_rs))                                          \
 433                 printk(fmt, ##__VA_ARGS__);                             \
 434 })
 435 #else
 436 /* No effect, but we still get type checking even in the !PRINTK case: */
 437 #define printk_ratelimited printk
 438 #endif
 439
 440 #define pr_emerg_ratelimited(fmt, ...) \
 441         printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 442 #define pr_alert_ratelimited(fmt, ...) \
 443         printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 444 #define pr_crit_ratelimited(fmt, ...) \
 445         printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 446 #define pr_err_ratelimited(fmt, ...) \
 447         printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 448 #define pr_warning_ratelimited(fmt, ...) \
 449         printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 450 #define pr_notice_ratelimited(fmt, ...) \
 451         printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 452 #define pr_info_ratelimited(fmt, ...) \
 453         printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 454 /* no pr_cont_ratelimited, don't do that... */
 455 /* If you are writing a driver, please use dev_dbg instead */
 456 #if defined(DEBUG)
 457 #define pr_debug_ratelimited(fmt, ...) \
 458         printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 459 #else
 460 #define pr_debug_ratelimited(fmt, ...) \
 461         ({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
 462                                      ##__VA_ARGS__); 0; })
 463 #endif
 464
 465 /*
 466  * General tracing related utility functions - trace_printk(),
 467  * tracing_on/tracing_off and tracing_start()/tracing_stop
 468  *
 469  * Use tracing_on/tracing_off when you want to quickly turn on or off
 470  * tracing. It simply enables or disables the recording of the trace events.
 471  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
 472  * file, which gives a means for the kernel and userspace to interact.
 473  * Place a tracing_off() in the kernel where you want tracing to end.
 474  * From user space, examine the trace, and then echo 1 > tracing_on
 475  * to continue tracing.
 476  *
 477  * tracing_stop/tracing_start has slightly more overhead. It is used
 478  * by things like suspend to ram where disabling the recording of the
 479  * trace is not enough, but tracing must actually stop because things
 480  * like calling smp_processor_id() may crash the system.
 481  *
 482  * Most likely, you want to use tracing_on/tracing_off.
 483  */
 484 #ifdef CONFIG_RING_BUFFER
 485 void tracing_on(void);
 486 void tracing_off(void);
 487 /* trace_off_permanent stops recording with no way to bring it back */
 488 void tracing_off_permanent(void);
 489 int tracing_is_on(void);
 490 #else
 491 static inline void tracing_on(void) { }
 492 static inline void tracing_off(void) { }
 493 static inline void tracing_off_permanent(void) { }
 494 static inline int tracing_is_on(void) { return 0; }
 495 #endif
 496 #ifdef CONFIG_TRACING
 497 extern void tracing_start(void);
 498 extern void tracing_stop(void);
 499 extern void ftrace_off_permanent(void);
 500
 501 extern void
 502 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
 503
 504 static inline void __attribute__ ((format (printf, 1, 2)))
 505 ____trace_printk_check_format(const char *fmt, ...)
 506 {
 507 }
 508 #define __trace_printk_check_format(fmt, args...)                       \
 509 do {                                                                    \
 510         if (0)                                                          \
 511                 ____trace_printk_check_format(fmt, ##args);             \
 512 } while (0)
 513
 514 /**
 515  * trace_printk - printf formatting in the ftrace buffer
 516  * @fmt: the printf format for printing
 517  *
 518  * Note: __trace_printk is an internal function for trace_printk and
 519  *       the @ip is passed in via the trace_printk macro.
 520  *
 521  * This function allows a kernel developer to debug fast path sections
 522  * that printk is not appropriate for. By scattering in various
 523  * printk like tracing in the code, a developer can quickly see
 524  * where problems are occurring.
 525  *
 526  * This is intended as a debugging tool for the developer only.
 527  * Please refrain from leaving trace_printks scattered around in
 528  * your code.
 529  */
 530
 531 #define trace_printk(fmt, args...)                                      \
 532 do {                                                                    \
 533         __trace_printk_check_format(fmt, ##args);                       \
 534         if (__builtin_constant_p(fmt)) {                                \
 535                 static const char *trace_printk_fmt                     \
 536                   __attribute__((section("__trace_printk_fmt"))) =      \
 537                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 538                                                                         \
 539                 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);   \
 540         } else                                                          \
 541                 __trace_printk(_THIS_IP_, fmt, ##args);         \
 542 } while (0)
 543
 544 extern int
 545 __trace_bprintk(unsigned long ip, const char *fmt, ...)
 546         __attribute__ ((format (printf, 2, 3)));
 547
 548 extern int
 549 __trace_printk(unsigned long ip, const char *fmt, ...)
 550         __attribute__ ((format (printf, 2, 3)));
 551
 552 /*
 553  * The double __builtin_constant_p is because gcc will give us an error
 554  * if we try to allocate the static variable to fmt if it is not a
 555  * constant. Even with the outer if statement.
 556  */
 557 #define ftrace_vprintk(fmt, vargs)                                      \
 558 do {                                                                    \
 559         if (__builtin_constant_p(fmt)) {                                \
 560                 static const char *trace_printk_fmt                     \
 561                   __attribute__((section("__trace_printk_fmt"))) =      \
 562                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 563                                                                         \
 564                 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);  \
 565         } else                                                          \
 566                 __ftrace_vprintk(_THIS_IP_, fmt, vargs);                \
 567 } while (0)
 568
 569 extern int
 570 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
 571
 572 extern int
 573 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
 574
 575 extern void ftrace_dump(void);
 576 #else
 577 static inline void
 578 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
 579 static inline int
 580 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
 581
 582 static inline void tracing_start(void) { }
 583 static inline void tracing_stop(void) { }
 584 static inline void ftrace_off_permanent(void) { }
 585 static inline int
 586 trace_printk(const char *fmt, ...)
 587 {
 588         return 0;
 589 }
 590 static inline int
 591 ftrace_vprintk(const char *fmt, va_list ap)
 592 {
 593         return 0;
 594 }
 595 static inline void ftrace_dump(void) { }
 596 #endif /* CONFIG_TRACING */
 597
 598 /*
 599  *      Display an IP address in readable format.
 600  */
 601
 602 #define NIPQUAD(addr) \
 603         ((unsigned char *)&addr)[0], \
 604         ((unsigned char *)&addr)[1], \
 605         ((unsigned char *)&addr)[2], \
 606         ((unsigned char *)&addr)[3]
 607 #define NIPQUAD_FMT "%u.%u.%u.%u"
 608
 609 /*
 610  * min()/max()/clamp() macros that also do
 611  * strict type-checking.. See the
 612  * "unnecessary" pointer comparison.
 613  */
 614 #define min(x, y) ({                            \
 615         typeof(x) _min1 = (x);                  \
 616         typeof(y) _min2 = (y);                  \
 617         (void) (&_min1 == &_min2);              \
 618         _min1 < _min2 ? _min1 : _min2; })
 619
 620 #define max(x, y) ({                            \
 621         typeof(x) _max1 = (x);                  \
 622         typeof(y) _max2 = (y);                  \
 623         (void) (&_max1 == &_max2);              \
 624         _max1 > _max2 ? _max1 : _max2; })
 625
 626 /**
 627  * clamp - return a value clamped to a given range with strict typechecking
 628  * @val: current value
 629  * @min: minimum allowable value
 630  * @max: maximum allowable value
 631  *
 632  * This macro does strict typechecking of min/max to make sure they are of the
 633  * same type as val.  See the unnecessary pointer comparisons.
 634  */
 635 #define clamp(val, min, max) ({                 \
 636         typeof(val) __val = (val);              \
 637         typeof(min) __min = (min);              \
 638         typeof(max) __max = (max);              \
 639         (void) (&__val == &__min);              \
 640         (void) (&__val == &__max);              \
 641         __val = __val < __min ? __min: __val;   \
 642         __val > __max ? __max: __val; })
 643
 644 /*
 645  * ..and if you can't take the strict
 646  * types, you can specify one yourself.
 647  *
 648  * Or not use min/max/clamp at all, of course.
 649  */
 650 #define min_t(type, x, y) ({                    \
 651         type __min1 = (x);                      \
 652         type __min2 = (y);                      \
 653         __min1 < __min2 ? __min1: __min2; })
 654
 655 #define max_t(type, x, y) ({                    \
 656         type __max1 = (x);                      \
 657         type __max2 = (y);                      \
 658         __max1 > __max2 ? __max1: __max2; })
 659
 660 /**
 661  * clamp_t - return a value clamped to a given range using a given type
 662  * @type: the type of variable to use
 663  * @val: current value
 664  * @min: minimum allowable value
 665  * @max: maximum allowable value
 666  *
 667  * This macro does no typechecking and uses temporary variables of type
 668  * 'type' to make all the comparisons.
 669  */
 670 #define clamp_t(type, val, min, max) ({         \
 671         type __val = (val);                     \
 672         type __min = (min);                     \
 673         type __max = (max);                     \
 674         __val = __val < __min ? __min: __val;   \
 675         __val > __max ? __max: __val; })
 676
 677 /**
 678  * clamp_val - return a value clamped to a given range using val's type
 679  * @val: current value
 680  * @min: minimum allowable value
 681  * @max: maximum allowable value
 682  *
 683  * This macro does no typechecking and uses temporary variables of whatever
 684  * type the input argument 'val' is.  This is useful when val is an unsigned
 685  * type and min and max are literals that will otherwise be assigned a signed
 686  * integer type.
 687  */
 688 #define clamp_val(val, min, max) ({             \
 689         typeof(val) __val = (val);              \
 690         typeof(val) __min = (min);              \
 691         typeof(val) __max = (max);              \
 692         __val = __val < __min ? __min: __val;   \
 693         __val > __max ? __max: __val; })
 694
 695
 696 /*
 697  * swap - swap value of @a and @b
 698  */
 699 #define swap(a, b) \
 700         do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
 701
 702 /**
 703  * container_of - cast a member of a structure out to the containing structure
 704  * @ptr:        the pointer to the member.
 705  * @type:       the type of the container struct this is embedded in.
 706  * @member:     the name of the member within the struct.
 707  *
 708  */
 709 #define container_of(ptr, type, member) ({                      \
 710         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 711         (type *)( (char *)__mptr - offsetof(type,member) );})
 712
 713 struct sysinfo;
 714 extern int do_sysinfo(struct sysinfo *info);
 715
 716 #endif /* __KERNEL__ */
 717
 718 #ifndef __EXPORTED_HEADERS__
 719 #ifndef __KERNEL__
 720 #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders
 721 #endif /* __KERNEL__ */
 722 #endif /* __EXPORTED_HEADERS__ */
 723
 724 #define SI_LOAD_SHIFT   16
 725 struct sysinfo {
 726         long uptime;                    /* Seconds since boot */
 727         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 728         unsigned long totalram;         /* Total usable main memory size */
 729         unsigned long freeram;          /* Available memory size */
 730         unsigned long sharedram;        /* Amount of shared memory */
 731         unsigned long bufferram;        /* Memory used by buffers */
 732         unsigned long totalswap;        /* Total swap space size */
 733         unsigned long freeswap;         /* swap space still available */
 734         unsigned short procs;           /* Number of current processes */
 735         unsigned short pad;             /* explicit padding for m68k */
 736         unsigned long totalhigh;        /* Total high memory size */
 737         unsigned long freehigh;         /* Available high memory size */
 738         unsigned int mem_unit;          /* Memory unit size in bytes */
 739         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 740 };
 741
 742 /* Force a compilation error if condition is true */
 743 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
 744
 745 /* Force a compilation error if condition is constant and true */
 746 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
 747
 748 /* Force a compilation error if condition is true, but also produce a
 749    result (of value 0 and type size_t), so the expression can be used
 750    e.g. in a structure initializer (or where-ever else comma expressions
 751    aren't permitted). */
 752 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
 753 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
 754
 755 /* Trap pasters of __FUNCTION__ at compile-time */
 756 #define __FUNCTION__ (__func__)
 757
 758 /* This helps us to avoid #ifdef CONFIG_NUMA */
 759 #ifdef CONFIG_NUMA
 760 #define NUMA_BUILD 1
 761 #else
 762 #define NUMA_BUILD 0
 763 #endif
 764
 765 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
 766 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 767 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
 768 #endif
 769
 770 #endif