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