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 #define __ALIGN_KERNEL(x, a)            __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
   8 #define __ALIGN_KERNEL_MASK(x, mask)    (((x) + (mask)) & ~(mask))
   9
  10 #ifdef __KERNEL__
  11
  12 #include <stdarg.h>
  13 #include <linux/linkage.h>
  14 #include <linux/stddef.h>
  15 #include <linux/types.h>
  16 #include <linux/compiler.h>
  17 #include <linux/bitops.h>
  18 #include <linux/log2.h>
  19 #include <linux/typecheck.h>
  20 #include <linux/dynamic_debug.h>
  21 #include <asm/byteorder.h>
  22 #include <asm/bug.h>
  23
  24 extern const char linux_banner[];
  25 extern const char linux_proc_banner[];
  26
  27 #define USHRT_MAX       ((u16)(~0U))
  28 #define SHRT_MAX        ((s16)(USHRT_MAX>>1))
  29 #define SHRT_MIN        ((s16)(-SHRT_MAX - 1))
  30 #define INT_MAX         ((int)(~0U>>1))
  31 #define INT_MIN         (-INT_MAX - 1)
  32 #define UINT_MAX        (~0U)
  33 #define LONG_MAX        ((long)(~0UL>>1))
  34 #define LONG_MIN        (-LONG_MAX - 1)
  35 #define ULONG_MAX       (~0UL)
  36 #define LLONG_MAX       ((long long)(~0ULL>>1))
  37 #define LLONG_MIN       (-LLONG_MAX - 1)
  38 #define ULLONG_MAX      (~0ULL)
  39
  40 #define STACK_MAGIC     0xdeadbeef
  41
  42 #define ALIGN(x, a)             __ALIGN_KERNEL((x), (a))
  43 #define __ALIGN_MASK(x, mask)   __ALIGN_KERNEL_MASK((x), (mask))
  44 #define PTR_ALIGN(p, a)         ((typeof(p))ALIGN((unsigned long)(p), (a)))
  45 #define IS_ALIGNED(x, a)                (((x) & ((typeof(x))(a) - 1)) == 0)
  46
  47 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
  48
  49 /*
  50  * This looks more complex than it should be. But we need to
  51  * get the type for the ~ right in round_down (it needs to be
  52  * as wide as the result!), and we want to evaluate the macro
  53  * arguments just once each.
  54  */
  55 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
  56 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
  57 #define round_down(x, y) ((x) & ~__round_mask(x, y))
  58
  59 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
  60 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
  61 #define roundup(x, y) (                                 \
  62 {                                                       \
  63         const typeof(y) __y = y;                        \
  64         (((x) + (__y - 1)) / __y) * __y;                \
  65 }                                                       \
  66 )
  67 #define rounddown(x, y) (                               \
  68 {                                                       \
  69         typeof(x) __x = (x);                            \
  70         __x - (__x % (y));                              \
  71 }                                                       \
  72 )
  73 #define DIV_ROUND_CLOSEST(x, divisor)(                  \
  74 {                                                       \
  75         typeof(divisor) __divisor = divisor;            \
  76         (((x) + ((__divisor) / 2)) / (__divisor));      \
  77 }                                                       \
  78 )
  79
  80 #define _RET_IP_                (unsigned long)__builtin_return_address(0)
  81 #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
  82
  83 #ifdef CONFIG_LBDAF
  84 # include <asm/div64.h>
  85 # define sector_div(a, b) do_div(a, b)
  86 #else
  87 # define sector_div(n, b)( \
  88 { \
  89         int _res; \
  90         _res = (n) % (b); \
  91         (n) /= (b); \
  92         _res; \
  93 } \
  94 )
  95 #endif
  96
  97 /**
  98  * upper_32_bits - return bits 32-63 of a number
  99  * @n: the number we're accessing
 100  *
 101  * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
 102  * the "right shift count >= width of type" warning when that quantity is
 103  * 32-bits.
 104  */
 105 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
 106
 107 /**
 108  * lower_32_bits - return bits 0-31 of a number
 109  * @n: the number we're accessing
 110  */
 111 #define lower_32_bits(n) ((u32)(n))
 112
 113 #define KERN_EMERG      "<0>"   /* system is unusable                   */
 114 #define KERN_ALERT      "<1>"   /* action must be taken immediately     */
 115 #define KERN_CRIT       "<2>"   /* critical conditions                  */
 116 #define KERN_ERR        "<3>"   /* error conditions                     */
 117 #define KERN_WARNING    "<4>"   /* warning conditions                   */
 118 #define KERN_NOTICE     "<5>"   /* normal but significant condition     */
 119 #define KERN_INFO       "<6>"   /* informational                        */
 120 #define KERN_DEBUG      "<7>"   /* debug-level messages                 */
 121
 122 /* Use the default kernel loglevel */
 123 #define KERN_DEFAULT    "<d>"
 124 /*
 125  * Annotation for a "continued" line of log printout (only done after a
 126  * line that had no enclosing \n). Only to be used by core/arch code
 127  * during early bootup (a continued line is not SMP-safe otherwise).
 128  */
 129 #define KERN_CONT       "<c>"
 130
 131 extern int console_printk[];
 132
 133 #define console_loglevel (console_printk[0])
 134 #define default_message_loglevel (console_printk[1])
 135 #define minimum_console_loglevel (console_printk[2])
 136 #define default_console_loglevel (console_printk[3])
 137
 138 struct completion;
 139 struct pt_regs;
 140 struct user;
 141
 142 #ifdef CONFIG_PREEMPT_VOLUNTARY
 143 extern int _cond_resched(void);
 144 # define might_resched() _cond_resched()
 145 #else
 146 # define might_resched() do { } while (0)
 147 #endif
 148
 149 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
 150   void __might_sleep(const char *file, int line, int preempt_offset);
 151 /**
 152  * might_sleep - annotation for functions that can sleep
 153  *
 154  * this macro will print a stack trace if it is executed in an atomic
 155  * context (spinlock, irq-handler, ...).
 156  *
 157  * This is a useful debugging help to be able to catch problems early and not
 158  * be bitten later when the calling function happens to sleep when it is not
 159  * supposed to.
 160  */
 161 # define might_sleep() \
 162         do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
 163 #else
 164   static inline void __might_sleep(const char *file, int line,
 165                                    int preempt_offset) { }
 166 # define might_sleep() do { might_resched(); } while (0)
 167 #endif
 168
 169 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
 170
 171 #define abs(x) ({                               \
 172                 long __x = (x);                 \
 173                 (__x < 0) ? -__x : __x;         \
 174         })
 175
 176 #define abs64(x) ({                             \
 177                 s64 __x = (x);                  \
 178                 (__x < 0) ? -__x : __x;         \
 179         })
 180
 181 #ifdef CONFIG_PROVE_LOCKING
 182 void might_fault(void);
 183 #else
 184 static inline void might_fault(void)
 185 {
 186         might_sleep();
 187 }
 188 #endif
 189
 190 struct va_format {
 191         const char *fmt;
 192         va_list *va;
 193 };
 194
 195 extern struct atomic_notifier_head panic_notifier_list;
 196 extern long (*panic_blink)(int state);
 197 NORET_TYPE void panic(const char * fmt, ...)
 198         __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
 199 extern void oops_enter(void);
 200 extern void oops_exit(void);
 201 void print_oops_end_marker(void);
 202 extern int oops_may_print(void);
 203 NORET_TYPE void do_exit(long error_code)
 204         ATTRIB_NORET;
 205 NORET_TYPE void complete_and_exit(struct completion *, long)
 206         ATTRIB_NORET;
 207 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
 208 extern long simple_strtol(const char *,char **,unsigned int);
 209 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
 210 extern long long simple_strtoll(const char *,char **,unsigned int);
 211 extern int __must_check strict_strtoul(const char *, unsigned int, unsigned long *);
 212 extern int __must_check strict_strtol(const char *, unsigned int, long *);
 213 extern int __must_check strict_strtoull(const char *, unsigned int, unsigned long long *);
 214 extern int __must_check strict_strtoll(const char *, unsigned int, long long *);
 215 extern int sprintf(char * buf, const char * fmt, ...)
 216         __attribute__ ((format (printf, 2, 3)));
 217 extern int vsprintf(char *buf, const char *, va_list)
 218         __attribute__ ((format (printf, 2, 0)));
 219 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
 220         __attribute__ ((format (printf, 3, 4)));
 221 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
 222         __attribute__ ((format (printf, 3, 0)));
 223 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
 224         __attribute__ ((format (printf, 3, 4)));
 225 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
 226         __attribute__ ((format (printf, 3, 0)));
 227 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
 228         __attribute__ ((format (printf, 2, 3)));
 229 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
 230
 231 extern int sscanf(const char *, const char *, ...)
 232         __attribute__ ((format (scanf, 2, 3)));
 233 extern int vsscanf(const char *, const char *, va_list)
 234         __attribute__ ((format (scanf, 2, 0)));
 235
 236 extern int get_option(char **str, int *pint);
 237 extern char *get_options(const char *str, int nints, int *ints);
 238 extern unsigned long long memparse(const char *ptr, char **retptr);
 239
 240 extern int core_kernel_text(unsigned long addr);
 241 extern int __kernel_text_address(unsigned long addr);
 242 extern int kernel_text_address(unsigned long addr);
 243 extern int func_ptr_is_kernel_text(void *ptr);
 244
 245 struct pid;
 246 extern struct pid *session_of_pgrp(struct pid *pgrp);
 247
 248 /*
 249  * FW_BUG
 250  * Add this to a message where you are sure the firmware is buggy or behaves
 251  * really stupid or out of spec. Be aware that the responsible BIOS developer
 252  * should be able to fix this issue or at least get a concrete idea of the
 253  * problem by reading your message without the need of looking at the kernel
 254  * code.
 255  *
 256  * Use it for definite and high priority BIOS bugs.
 257  *
 258  * FW_WARN
 259  * Use it for not that clear (e.g. could the kernel messed up things already?)
 260  * and medium priority BIOS bugs.
 261  *
 262  * FW_INFO
 263  * Use this one if you want to tell the user or vendor about something
 264  * suspicious, but generally harmless related to the firmware.
 265  *
 266  * Use it for information or very low priority BIOS bugs.
 267  */
 268 #define FW_BUG          "[Firmware Bug]: "
 269 #define FW_WARN         "[Firmware Warn]: "
 270 #define FW_INFO         "[Firmware Info]: "
 271
 272 /*
 273  * HW_ERR
 274  * Add this to a message for hardware errors, so that user can report
 275  * it to hardware vendor instead of LKML or software vendor.
 276  */
 277 #define HW_ERR          "[Hardware Error]: "
 278
 279 #ifdef CONFIG_PRINTK
 280 asmlinkage int vprintk(const char *fmt, va_list args)
 281         __attribute__ ((format (printf, 1, 0)));
 282 asmlinkage int printk(const char * fmt, ...)
 283         __attribute__ ((format (printf, 1, 2))) __cold;
 284
 285 /*
 286  * Please don't use printk_ratelimit(), because it shares ratelimiting state
 287  * with all other unrelated printk_ratelimit() callsites.  Instead use
 288  * printk_ratelimited() or plain old __ratelimit().
 289  */
 290 extern int __printk_ratelimit(const char *func);
 291 #define printk_ratelimit() __printk_ratelimit(__func__)
 292 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 293                                    unsigned int interval_msec);
 294
 295 extern int printk_delay_msec;
 296 extern int dmesg_restrict;
 297
 298 /*
 299  * Print a one-time message (analogous to WARN_ONCE() et al):
 300  */
 301 #define printk_once(x...) ({                    \
 302         static bool __print_once;               \
 303                                                 \
 304         if (!__print_once) {                    \
 305                 __print_once = true;            \
 306                 printk(x);                      \
 307         }                                       \
 308 })
 309
 310 void log_buf_kexec_setup(void);
 311 #else
 312 static inline int vprintk(const char *s, va_list args)
 313         __attribute__ ((format (printf, 1, 0)));
 314 static inline int vprintk(const char *s, va_list args) { return 0; }
 315 static inline int printk(const char *s, ...)
 316         __attribute__ ((format (printf, 1, 2)));
 317 static inline int __cold printk(const char *s, ...) { return 0; }
 318 static inline int printk_ratelimit(void) { return 0; }
 319 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
 320                                           unsigned int interval_msec)   \
 321                 { return false; }
 322
 323 /* No effect, but we still get type checking even in the !PRINTK case: */
 324 #define printk_once(x...) printk(x)
 325
 326 static inline void log_buf_kexec_setup(void)
 327 {
 328 }
 329 #endif
 330
 331 /*
 332  * Dummy printk for disabled debugging statements to use whilst maintaining
 333  * gcc's format and side-effect checking.
 334  */
 335 static inline __attribute__ ((format (printf, 1, 2)))
 336 int no_printk(const char *s, ...) { return 0; }
 337
 338 extern int printk_needs_cpu(int cpu);
 339 extern void printk_tick(void);
 340
 341 extern void asmlinkage __attribute__((format(printf, 1, 2)))
 342         early_printk(const char *fmt, ...);
 343
 344 unsigned long int_sqrt(unsigned long);
 345
 346 static inline void console_silent(void)
 347 {
 348         console_loglevel = 0;
 349 }
 350
 351 static inline void console_verbose(void)
 352 {
 353         if (console_loglevel)
 354                 console_loglevel = 15;
 355 }
 356
 357 extern void bust_spinlocks(int yes);
 358 extern void wake_up_klogd(void);
 359 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 360 extern int panic_timeout;
 361 extern int panic_on_oops;
 362 extern int panic_on_unrecovered_nmi;
 363 extern int panic_on_io_nmi;
 364 extern const char *print_tainted(void);
 365 extern void add_taint(unsigned flag);
 366 extern int test_taint(unsigned flag);
 367 extern unsigned long get_taint(void);
 368 extern int root_mountflags;
 369
 370 /* Values used for system_state */
 371 extern enum system_states {
 372         SYSTEM_BOOTING,
 373         SYSTEM_RUNNING,
 374         SYSTEM_HALT,
 375         SYSTEM_POWER_OFF,
 376         SYSTEM_RESTART,
 377         SYSTEM_SUSPEND_DISK,
 378 } system_state;
 379
 380 #define TAINT_PROPRIETARY_MODULE        0
 381 #define TAINT_FORCED_MODULE             1
 382 #define TAINT_UNSAFE_SMP                2
 383 #define TAINT_FORCED_RMMOD              3
 384 #define TAINT_MACHINE_CHECK             4
 385 #define TAINT_BAD_PAGE                  5
 386 #define TAINT_USER                      6
 387 #define TAINT_DIE                       7
 388 #define TAINT_OVERRIDDEN_ACPI_TABLE     8
 389 #define TAINT_WARN                      9
 390 #define TAINT_CRAP                      10
 391 #define TAINT_FIRMWARE_WORKAROUND       11
 392
 393 extern void dump_stack(void) __cold;
 394
 395 enum {
 396         DUMP_PREFIX_NONE,
 397         DUMP_PREFIX_ADDRESS,
 398         DUMP_PREFIX_OFFSET
 399 };
 400 extern void hex_dump_to_buffer(const void *buf, size_t len,
 401                                 int rowsize, int groupsize,
 402                                 char *linebuf, size_t linebuflen, bool ascii);
 403 extern void print_hex_dump(const char *level, const char *prefix_str,
 404                                 int prefix_type, int rowsize, int groupsize,
 405                                 const void *buf, size_t len, bool ascii);
 406 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 407                         const void *buf, size_t len);
 408
 409 extern const char hex_asc[];
 410 #define hex_asc_lo(x)   hex_asc[((x) & 0x0f)]
 411 #define hex_asc_hi(x)   hex_asc[((x) & 0xf0) >> 4]
 412
 413 static inline char *pack_hex_byte(char *buf, u8 byte)
 414 {
 415         *buf++ = hex_asc_hi(byte);
 416         *buf++ = hex_asc_lo(byte);
 417         return buf;
 418 }
 419
 420 extern int hex_to_bin(char ch);
 421
 422 #ifndef pr_fmt
 423 #define pr_fmt(fmt) fmt
 424 #endif
 425
 426 #define pr_emerg(fmt, ...) \
 427         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 428 #define pr_alert(fmt, ...) \
 429         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 430 #define pr_crit(fmt, ...) \
 431         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 432 #define pr_err(fmt, ...) \
 433         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 434 #define pr_warning(fmt, ...) \
 435         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 436 #define pr_warn pr_warning
 437 #define pr_notice(fmt, ...) \
 438         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 439 #define pr_info(fmt, ...) \
 440         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 441 #define pr_cont(fmt, ...) \
 442         printk(KERN_CONT fmt, ##__VA_ARGS__)
 443
 444 /* pr_devel() should produce zero code unless DEBUG is defined */
 445 #ifdef DEBUG
 446 #define pr_devel(fmt, ...) \
 447         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 448 #else
 449 #define pr_devel(fmt, ...) \
 450         ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
 451 #endif
 452
 453 /* If you are writing a driver, please use dev_dbg instead */
 454 #if defined(DEBUG)
 455 #define pr_debug(fmt, ...) \
 456         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 457 #elif defined(CONFIG_DYNAMIC_DEBUG)
 458 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
 459 #define pr_debug(fmt, ...) \
 460         dynamic_pr_debug(fmt, ##__VA_ARGS__)
 461 #else
 462 #define pr_debug(fmt, ...) \
 463         ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
 464 #endif
 465
 466 /*
 467  * ratelimited messages with local ratelimit_state,
 468  * no local ratelimit_state used in the !PRINTK case
 469  */
 470 #ifdef CONFIG_PRINTK
 471 #define printk_ratelimited(fmt, ...)  ({                                \
 472         static DEFINE_RATELIMIT_STATE(_rs,                              \
 473                                       DEFAULT_RATELIMIT_INTERVAL,       \
 474                                       DEFAULT_RATELIMIT_BURST);         \
 475                                                                         \
 476         if (__ratelimit(&_rs))                                          \
 477                 printk(fmt, ##__VA_ARGS__);                             \
 478 })
 479 #else
 480 /* No effect, but we still get type checking even in the !PRINTK case: */
 481 #define printk_ratelimited printk
 482 #endif
 483
 484 #define pr_emerg_ratelimited(fmt, ...) \
 485         printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 486 #define pr_alert_ratelimited(fmt, ...) \
 487         printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 488 #define pr_crit_ratelimited(fmt, ...) \
 489         printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 490 #define pr_err_ratelimited(fmt, ...) \
 491         printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 492 #define pr_warning_ratelimited(fmt, ...) \
 493         printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 494 #define pr_warn_ratelimited pr_warning_ratelimited
 495 #define pr_notice_ratelimited(fmt, ...) \
 496         printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 497 #define pr_info_ratelimited(fmt, ...) \
 498         printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 499 /* no pr_cont_ratelimited, don't do that... */
 500 /* If you are writing a driver, please use dev_dbg instead */
 501 #if defined(DEBUG)
 502 #define pr_debug_ratelimited(fmt, ...) \
 503         printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 504 #else
 505 #define pr_debug_ratelimited(fmt, ...) \
 506         ({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
 507                                      ##__VA_ARGS__); 0; })
 508 #endif
 509
 510 /*
 511  * General tracing related utility functions - trace_printk(),
 512  * tracing_on/tracing_off and tracing_start()/tracing_stop
 513  *
 514  * Use tracing_on/tracing_off when you want to quickly turn on or off
 515  * tracing. It simply enables or disables the recording of the trace events.
 516  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
 517  * file, which gives a means for the kernel and userspace to interact.
 518  * Place a tracing_off() in the kernel where you want tracing to end.
 519  * From user space, examine the trace, and then echo 1 > tracing_on
 520  * to continue tracing.
 521  *
 522  * tracing_stop/tracing_start has slightly more overhead. It is used
 523  * by things like suspend to ram where disabling the recording of the
 524  * trace is not enough, but tracing must actually stop because things
 525  * like calling smp_processor_id() may crash the system.
 526  *
 527  * Most likely, you want to use tracing_on/tracing_off.
 528  */
 529 #ifdef CONFIG_RING_BUFFER
 530 void tracing_on(void);
 531 void tracing_off(void);
 532 /* trace_off_permanent stops recording with no way to bring it back */
 533 void tracing_off_permanent(void);
 534 int tracing_is_on(void);
 535 #else
 536 static inline void tracing_on(void) { }
 537 static inline void tracing_off(void) { }
 538 static inline void tracing_off_permanent(void) { }
 539 static inline int tracing_is_on(void) { return 0; }
 540 #endif
 541
 542 enum ftrace_dump_mode {
 543         DUMP_NONE,
 544         DUMP_ALL,
 545         DUMP_ORIG,
 546 };
 547
 548 #ifdef CONFIG_TRACING
 549 extern void tracing_start(void);
 550 extern void tracing_stop(void);
 551 extern void ftrace_off_permanent(void);
 552
 553 static inline void __attribute__ ((format (printf, 1, 2)))
 554 ____trace_printk_check_format(const char *fmt, ...)
 555 {
 556 }
 557 #define __trace_printk_check_format(fmt, args...)                       \
 558 do {                                                                    \
 559         if (0)                                                          \
 560                 ____trace_printk_check_format(fmt, ##args);             \
 561 } while (0)
 562
 563 /**
 564  * trace_printk - printf formatting in the ftrace buffer
 565  * @fmt: the printf format for printing
 566  *
 567  * Note: __trace_printk is an internal function for trace_printk and
 568  *       the @ip is passed in via the trace_printk macro.
 569  *
 570  * This function allows a kernel developer to debug fast path sections
 571  * that printk is not appropriate for. By scattering in various
 572  * printk like tracing in the code, a developer can quickly see
 573  * where problems are occurring.
 574  *
 575  * This is intended as a debugging tool for the developer only.
 576  * Please refrain from leaving trace_printks scattered around in
 577  * your code.
 578  */
 579
 580 #define trace_printk(fmt, args...)                                      \
 581 do {                                                                    \
 582         __trace_printk_check_format(fmt, ##args);                       \
 583         if (__builtin_constant_p(fmt)) {                                \
 584                 static const char *trace_printk_fmt                     \
 585                   __attribute__((section("__trace_printk_fmt"))) =      \
 586                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 587                                                                         \
 588                 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);   \
 589         } else                                                          \
 590                 __trace_printk(_THIS_IP_, fmt, ##args);         \
 591 } while (0)
 592
 593 extern int
 594 __trace_bprintk(unsigned long ip, const char *fmt, ...)
 595         __attribute__ ((format (printf, 2, 3)));
 596
 597 extern int
 598 __trace_printk(unsigned long ip, const char *fmt, ...)
 599         __attribute__ ((format (printf, 2, 3)));
 600
 601 extern void trace_dump_stack(void);
 602
 603 /*
 604  * The double __builtin_constant_p is because gcc will give us an error
 605  * if we try to allocate the static variable to fmt if it is not a
 606  * constant. Even with the outer if statement.
 607  */
 608 #define ftrace_vprintk(fmt, vargs)                                      \
 609 do {                                                                    \
 610         if (__builtin_constant_p(fmt)) {                                \
 611                 static const char *trace_printk_fmt                     \
 612                   __attribute__((section("__trace_printk_fmt"))) =      \
 613                         __builtin_constant_p(fmt) ? fmt : NULL;         \
 614                                                                         \
 615                 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);  \
 616         } else                                                          \
 617                 __ftrace_vprintk(_THIS_IP_, fmt, vargs);                \
 618 } while (0)
 619
 620 extern int
 621 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
 622
 623 extern int
 624 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
 625
 626 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
 627 #else
 628 static inline int
 629 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
 630
 631 static inline void tracing_start(void) { }
 632 static inline void tracing_stop(void) { }
 633 static inline void ftrace_off_permanent(void) { }
 634 static inline void trace_dump_stack(void) { }
 635 static inline int
 636 trace_printk(const char *fmt, ...)
 637 {
 638         return 0;
 639 }
 640 static inline int
 641 ftrace_vprintk(const char *fmt, va_list ap)
 642 {
 643         return 0;
 644 }
 645 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
 646 #endif /* CONFIG_TRACING */
 647
 648 /*
 649  * min()/max()/clamp() macros that also do
 650  * strict type-checking.. See the
 651  * "unnecessary" pointer comparison.
 652  */
 653 #define min(x, y) ({                            \
 654         typeof(x) _min1 = (x);                  \
 655         typeof(y) _min2 = (y);                  \
 656         (void) (&_min1 == &_min2);              \
 657         _min1 < _min2 ? _min1 : _min2; })
 658
 659 #define max(x, y) ({                            \
 660         typeof(x) _max1 = (x);                  \
 661         typeof(y) _max2 = (y);                  \
 662         (void) (&_max1 == &_max2);              \
 663         _max1 > _max2 ? _max1 : _max2; })
 664
 665 #define min3(x, y, z) ({                        \
 666         typeof(x) _min1 = (x);                  \
 667         typeof(y) _min2 = (y);                  \
 668         typeof(z) _min3 = (z);                  \
 669         (void) (&_min1 == &_min2);              \
 670         (void) (&_min1 == &_min3);              \
 671         _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
 672                 (_min2 < _min3 ? _min2 : _min3); })
 673
 674 #define max3(x, y, z) ({                        \
 675         typeof(x) _max1 = (x);                  \
 676         typeof(y) _max2 = (y);                  \
 677         typeof(z) _max3 = (z);                  \
 678         (void) (&_max1 == &_max2);              \
 679         (void) (&_max1 == &_max3);              \
 680         _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
 681                 (_max2 > _max3 ? _max2 : _max3); })
 682
 683 /**
 684  * min_not_zero - return the minimum that is _not_ zero, unless both are zero
 685  * @x: value1
 686  * @y: value2
 687  */
 688 #define min_not_zero(x, y) ({                   \
 689         typeof(x) __x = (x);                    \
 690         typeof(y) __y = (y);                    \
 691         __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
 692
 693 /**
 694  * clamp - return a value clamped to a given range with strict typechecking
 695  * @val: current value
 696  * @min: minimum allowable value
 697  * @max: maximum allowable value
 698  *
 699  * This macro does strict typechecking of min/max to make sure they are of the
 700  * same type as val.  See the unnecessary pointer comparisons.
 701  */
 702 #define clamp(val, min, max) ({                 \
 703         typeof(val) __val = (val);              \
 704         typeof(min) __min = (min);              \
 705         typeof(max) __max = (max);              \
 706         (void) (&__val == &__min);              \
 707         (void) (&__val == &__max);              \
 708         __val = __val < __min ? __min: __val;   \
 709         __val > __max ? __max: __val; })
 710
 711 /*
 712  * ..and if you can't take the strict
 713  * types, you can specify one yourself.
 714  *
 715  * Or not use min/max/clamp at all, of course.
 716  */
 717 #define min_t(type, x, y) ({                    \
 718         type __min1 = (x);                      \
 719         type __min2 = (y);                      \
 720         __min1 < __min2 ? __min1: __min2; })
 721
 722 #define max_t(type, x, y) ({                    \
 723         type __max1 = (x);                      \
 724         type __max2 = (y);                      \
 725         __max1 > __max2 ? __max1: __max2; })
 726
 727 /**
 728  * clamp_t - return a value clamped to a given range using a given type
 729  * @type: the type of variable to use
 730  * @val: current value
 731  * @min: minimum allowable value
 732  * @max: maximum allowable value
 733  *
 734  * This macro does no typechecking and uses temporary variables of type
 735  * 'type' to make all the comparisons.
 736  */
 737 #define clamp_t(type, val, min, max) ({         \
 738         type __val = (val);                     \
 739         type __min = (min);                     \
 740         type __max = (max);                     \
 741         __val = __val < __min ? __min: __val;   \
 742         __val > __max ? __max: __val; })
 743
 744 /**
 745  * clamp_val - return a value clamped to a given range using val's type
 746  * @val: current value
 747  * @min: minimum allowable value
 748  * @max: maximum allowable value
 749  *
 750  * This macro does no typechecking and uses temporary variables of whatever
 751  * type the input argument 'val' is.  This is useful when val is an unsigned
 752  * type and min and max are literals that will otherwise be assigned a signed
 753  * integer type.
 754  */
 755 #define clamp_val(val, min, max) ({             \
 756         typeof(val) __val = (val);              \
 757         typeof(val) __min = (min);              \
 758         typeof(val) __max = (max);              \
 759         __val = __val < __min ? __min: __val;   \
 760         __val > __max ? __max: __val; })
 761
 762
 763 /*
 764  * swap - swap value of @a and @b
 765  */
 766 #define swap(a, b) \
 767         do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
 768
 769 /**
 770  * container_of - cast a member of a structure out to the containing structure
 771  * @ptr:        the pointer to the member.
 772  * @type:       the type of the container struct this is embedded in.
 773  * @member:     the name of the member within the struct.
 774  *
 775  */
 776 #define container_of(ptr, type, member) ({                      \
 777         const typeof( ((type *)0)->member ) *__mptr = (ptr);    \
 778         (type *)( (char *)__mptr - offsetof(type,member) );})
 779
 780 struct sysinfo;
 781 extern int do_sysinfo(struct sysinfo *info);
 782
 783 #endif /* __KERNEL__ */
 784
 785 #define SI_LOAD_SHIFT   16
 786 struct sysinfo {
 787         long uptime;                    /* Seconds since boot */
 788         unsigned long loads[3];         /* 1, 5, and 15 minute load averages */
 789         unsigned long totalram;         /* Total usable main memory size */
 790         unsigned long freeram;          /* Available memory size */
 791         unsigned long sharedram;        /* Amount of shared memory */
 792         unsigned long bufferram;        /* Memory used by buffers */
 793         unsigned long totalswap;        /* Total swap space size */
 794         unsigned long freeswap;         /* swap space still available */
 795         unsigned short procs;           /* Number of current processes */
 796         unsigned short pad;             /* explicit padding for m68k */
 797         unsigned long totalhigh;        /* Total high memory size */
 798         unsigned long freehigh;         /* Available high memory size */
 799         unsigned int mem_unit;          /* Memory unit size in bytes */
 800         char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
 801 };
 802
 803 /* Force a compilation error if condition is true */
 804 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
 805
 806 /* Force a compilation error if condition is constant and true */
 807 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
 808
 809 /* Force a compilation error if a constant expression is not a power of 2 */
 810 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)                  \
 811         BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
 812
 813 /* Force a compilation error if condition is true, but also produce a
 814    result (of value 0 and type size_t), so the expression can be used
 815    e.g. in a structure initializer (or where-ever else comma expressions
 816    aren't permitted). */
 817 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
 818 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
 819
 820 /* Trap pasters of __FUNCTION__ at compile-time */
 821 #define __FUNCTION__ (__func__)
 822
 823 /* This helps us to avoid #ifdef CONFIG_NUMA */
 824 #ifdef CONFIG_NUMA
 825 #define NUMA_BUILD 1
 826 #else
 827 #define NUMA_BUILD 0
 828 #endif
 829
 830 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
 831 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
 832 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
 833 #endif
 834
 835 #endif