1 #ifndef _LINUX_KERNEL_H 2 #define _LINUX_KERNEL_H 3 4 5 #include <stdarg.h> 6 #include <linux/linkage.h> 7 #include <linux/stddef.h> 8 #include <linux/types.h> 9 #include <linux/compiler.h> 10 #include <linux/bitops.h> 11 #include <linux/log2.h> 12 #include <linux/typecheck.h> 13 #include <linux/printk.h> 14 #include <linux/dynamic_debug.h> 15 #include <asm/byteorder.h> 16 #include <uapi/linux/kernel.h> 17 18 #define USHRT_MAX ((u16)(~0U)) 19 #define SHRT_MAX ((s16)(USHRT_MAX>>1)) 20 #define SHRT_MIN ((s16)(-SHRT_MAX - 1)) 21 #define INT_MAX ((int)(~0U>>1)) 22 #define INT_MIN (-INT_MAX - 1) 23 #define UINT_MAX (~0U) 24 #define LONG_MAX ((long)(~0UL>>1)) 25 #define LONG_MIN (-LONG_MAX - 1) 26 #define ULONG_MAX (~0UL) 27 #define LLONG_MAX ((long long)(~0ULL>>1)) 28 #define LLONG_MIN (-LLONG_MAX - 1) 29 #define ULLONG_MAX (~0ULL) 30 #define SIZE_MAX (~(size_t)0) 31 32 #define STACK_MAGIC 0xdeadbeef 33 34 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) 35 36 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) 37 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) 38 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) 39 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) 40 41 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) 42 43 /* 44 * This looks more complex than it should be. But we need to 45 * get the type for the ~ right in round_down (it needs to be 46 * as wide as the result!), and we want to evaluate the macro 47 * arguments just once each. 48 */ 49 #define __round_mask(x, y) ((__typeof__(x))((y)-1)) 50 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 51 #define round_down(x, y) ((x) & ~__round_mask(x, y)) 52 53 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 54 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) 55 #define DIV_ROUND_UP_ULL(ll,d) \ 56 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; }) 57 58 #if BITS_PER_LONG == 32 59 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) 60 #else 61 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) 62 #endif 63 64 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */ 65 #define roundup(x, y) ( \ 66 { \ 67 const typeof(y) __y = y; \ 68 (((x) + (__y - 1)) / __y) * __y; \ 69 } \ 70 ) 71 #define rounddown(x, y) ( \ 72 { \ 73 typeof(x) __x = (x); \ 74 __x - (__x % (y)); \ 75 } \ 76 ) 77 78 /* 79 * Divide positive or negative dividend by positive divisor and round 80 * to closest integer. Result is undefined for negative divisors and 81 * for negative dividends if the divisor variable type is unsigned. 82 */ 83 #define DIV_ROUND_CLOSEST(x, divisor)( \ 84 { \ 85 typeof(x) __x = x; \ 86 typeof(divisor) __d = divisor; \ 87 (((typeof(x))-1) > 0 || \ 88 ((typeof(divisor))-1) > 0 || (__x) > 0) ? \ 89 (((__x) + ((__d) / 2)) / (__d)) : \ 90 (((__x) - ((__d) / 2)) / (__d)); \ 91 } \ 92 ) 93 94 /* 95 * Multiplies an integer by a fraction, while avoiding unnecessary 96 * overflow or loss of precision. 97 */ 98 #define mult_frac(x, numer, denom)( \ 99 { \ 100 typeof(x) quot = (x) / (denom); \ 101 typeof(x) rem = (x) % (denom); \ 102 (quot * (numer)) + ((rem * (numer)) / (denom)); \ 103 } \ 104 ) 105 106 107 #define _RET_IP_ (unsigned long)__builtin_return_address(0) 108 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 109 110 #ifdef CONFIG_LBDAF 111 # include <asm/div64.h> 112 # define sector_div(a, b) do_div(a, b) 113 #else 114 # define sector_div(n, b)( \ 115 { \ 116 int _res; \ 117 _res = (n) % (b); \ 118 (n) /= (b); \ 119 _res; \ 120 } \ 121 ) 122 #endif 123 124 /** 125 * upper_32_bits - return bits 32-63 of a number 126 * @n: the number we're accessing 127 * 128 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 129 * the "right shift count >= width of type" warning when that quantity is 130 * 32-bits. 131 */ 132 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 133 134 /** 135 * lower_32_bits - return bits 0-31 of a number 136 * @n: the number we're accessing 137 */ 138 #define lower_32_bits(n) ((u32)(n)) 139 140 struct completion; 141 struct pt_regs; 142 struct user; 143 144 #ifdef CONFIG_PREEMPT_VOLUNTARY 145 extern int _cond_resched(void); 146 # define might_resched() _cond_resched() 147 #else 148 # define might_resched() do { } while (0) 149 #endif 150 151 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 152 void __might_sleep(const char *file, int line, int preempt_offset); 153 /** 154 * might_sleep - annotation for functions that can sleep 155 * 156 * this macro will print a stack trace if it is executed in an atomic 157 * context (spinlock, irq-handler, ...). 158 * 159 * This is a useful debugging help to be able to catch problems early and not 160 * be bitten later when the calling function happens to sleep when it is not 161 * supposed to. 162 */ 163 # define might_sleep() \ 164 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 165 #else 166 static inline void __might_sleep(const char *file, int line, 167 int preempt_offset) { } 168 # define might_sleep() do { might_resched(); } while (0) 169 #endif 170 171 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 172 173 /* 174 * abs() handles unsigned and signed longs, ints, shorts and chars. For all 175 * input types abs() returns a signed long. 176 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64() 177 * for those. 178 */ 179 #define abs(x) ({ \ 180 long ret; \ 181 if (sizeof(x) == sizeof(long)) { \ 182 long __x = (x); \ 183 ret = (__x < 0) ? -__x : __x; \ 184 } else { \ 185 int __x = (x); \ 186 ret = (__x < 0) ? -__x : __x; \ 187 } \ 188 ret; \ 189 }) 190 191 #define abs64(x) ({ \ 192 s64 __x = (x); \ 193 (__x < 0) ? -__x : __x; \ 194 }) 195 196 #ifdef CONFIG_PROVE_LOCKING 197 void might_fault(void); 198 #else 199 static inline void might_fault(void) 200 { 201 might_sleep(); 202 } 203 #endif 204 205 extern struct atomic_notifier_head panic_notifier_list; 206 extern long (*panic_blink)(int state); 207 __printf(1, 2) 208 void panic(const char *fmt, ...) 209 __noreturn __cold; 210 extern void oops_enter(void); 211 extern void oops_exit(void); 212 void print_oops_end_marker(void); 213 extern int oops_may_print(void); 214 void do_exit(long error_code) 215 __noreturn; 216 void complete_and_exit(struct completion *, long) 217 __noreturn; 218 219 /* Internal, do not use. */ 220 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 221 int __must_check _kstrtol(const char *s, unsigned int base, long *res); 222 223 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 224 int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 225 226 /** 227 * kstrtoul - convert a string to an unsigned long 228 * @s: The start of the string. The string must be null-terminated, and may also 229 * include a single newline before its terminating null. The first character 230 * may also be a plus sign, but not a minus sign. 231 * @base: The number base to use. The maximum supported base is 16. If base is 232 * given as 0, then the base of the string is automatically detected with the 233 * conventional semantics - If it begins with 0x the number will be parsed as a 234 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 235 * parsed as an octal number. Otherwise it will be parsed as a decimal. 236 * @res: Where to write the result of the conversion on success. 237 * 238 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 239 * Used as a replacement for the obsolete simple_strtoull. Return code must 240 * be checked. 241 */ 242 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) 243 { 244 /* 245 * We want to shortcut function call, but 246 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. 247 */ 248 if (sizeof(unsigned long) == sizeof(unsigned long long) && 249 __alignof__(unsigned long) == __alignof__(unsigned long long)) 250 return kstrtoull(s, base, (unsigned long long *)res); 251 else 252 return _kstrtoul(s, base, res); 253 } 254 255 /** 256 * kstrtol - convert a string to a long 257 * @s: The start of the string. The string must be null-terminated, and may also 258 * include a single newline before its terminating null. The first character 259 * may also be a plus sign or a minus sign. 260 * @base: The number base to use. The maximum supported base is 16. If base is 261 * given as 0, then the base of the string is automatically detected with the 262 * conventional semantics - If it begins with 0x the number will be parsed as a 263 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 264 * parsed as an octal number. Otherwise it will be parsed as a decimal. 265 * @res: Where to write the result of the conversion on success. 266 * 267 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 268 * Used as a replacement for the obsolete simple_strtoull. Return code must 269 * be checked. 270 */ 271 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) 272 { 273 /* 274 * We want to shortcut function call, but 275 * __builtin_types_compatible_p(long, long long) = 0. 276 */ 277 if (sizeof(long) == sizeof(long long) && 278 __alignof__(long) == __alignof__(long long)) 279 return kstrtoll(s, base, (long long *)res); 280 else 281 return _kstrtol(s, base, res); 282 } 283 284 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 285 int __must_check kstrtoint(const char *s, unsigned int base, int *res); 286 287 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 288 { 289 return kstrtoull(s, base, res); 290 } 291 292 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 293 { 294 return kstrtoll(s, base, res); 295 } 296 297 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 298 { 299 return kstrtouint(s, base, res); 300 } 301 302 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 303 { 304 return kstrtoint(s, base, res); 305 } 306 307 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 308 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 309 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 310 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 311 312 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 313 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 314 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 315 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 316 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 317 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 318 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 319 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 320 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 321 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 322 323 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) 324 { 325 return kstrtoull_from_user(s, count, base, res); 326 } 327 328 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) 329 { 330 return kstrtoll_from_user(s, count, base, res); 331 } 332 333 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) 334 { 335 return kstrtouint_from_user(s, count, base, res); 336 } 337 338 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) 339 { 340 return kstrtoint_from_user(s, count, base, res); 341 } 342 343 /* Obsolete, do not use. Use kstrto<foo> instead */ 344 345 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 346 extern long simple_strtol(const char *,char **,unsigned int); 347 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 348 extern long long simple_strtoll(const char *,char **,unsigned int); 349 #define strict_strtoul kstrtoul 350 #define strict_strtol kstrtol 351 #define strict_strtoull kstrtoull 352 #define strict_strtoll kstrtoll 353 354 extern int num_to_str(char *buf, int size, unsigned long long num); 355 356 /* lib/printf utilities */ 357 358 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 359 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 360 extern __printf(3, 4) 361 int snprintf(char *buf, size_t size, const char *fmt, ...); 362 extern __printf(3, 0) 363 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 364 extern __printf(3, 4) 365 int scnprintf(char *buf, size_t size, const char *fmt, ...); 366 extern __printf(3, 0) 367 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 368 extern __printf(2, 3) 369 char *kasprintf(gfp_t gfp, const char *fmt, ...); 370 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 371 372 extern __scanf(2, 3) 373 int sscanf(const char *, const char *, ...); 374 extern __scanf(2, 0) 375 int vsscanf(const char *, const char *, va_list); 376 377 extern int get_option(char **str, int *pint); 378 extern char *get_options(const char *str, int nints, int *ints); 379 extern unsigned long long memparse(const char *ptr, char **retptr); 380 381 extern int core_kernel_text(unsigned long addr); 382 extern int core_kernel_data(unsigned long addr); 383 extern int __kernel_text_address(unsigned long addr); 384 extern int kernel_text_address(unsigned long addr); 385 extern int func_ptr_is_kernel_text(void *ptr); 386 387 struct pid; 388 extern struct pid *session_of_pgrp(struct pid *pgrp); 389 390 unsigned long int_sqrt(unsigned long); 391 392 extern void bust_spinlocks(int yes); 393 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 394 extern int panic_timeout; 395 extern int panic_on_oops; 396 extern int panic_on_unrecovered_nmi; 397 extern int panic_on_io_nmi; 398 extern int sysctl_panic_on_stackoverflow; 399 extern const char *print_tainted(void); 400 enum lockdep_ok { 401 LOCKDEP_STILL_OK, 402 LOCKDEP_NOW_UNRELIABLE 403 }; 404 extern void add_taint(unsigned flag, enum lockdep_ok); 405 extern int test_taint(unsigned flag); 406 extern unsigned long get_taint(void); 407 extern int root_mountflags; 408 409 extern bool early_boot_irqs_disabled; 410 411 /* Values used for system_state */ 412 extern enum system_states { 413 SYSTEM_BOOTING, 414 SYSTEM_RUNNING, 415 SYSTEM_HALT, 416 SYSTEM_POWER_OFF, 417 SYSTEM_RESTART, 418 } system_state; 419 420 #define TAINT_PROPRIETARY_MODULE 0 421 #define TAINT_FORCED_MODULE 1 422 #define TAINT_UNSAFE_SMP 2 423 #define TAINT_FORCED_RMMOD 3 424 #define TAINT_MACHINE_CHECK 4 425 #define TAINT_BAD_PAGE 5 426 #define TAINT_USER 6 427 #define TAINT_DIE 7 428 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 429 #define TAINT_WARN 9 430 #define TAINT_CRAP 10 431 #define TAINT_FIRMWARE_WORKAROUND 11 432 #define TAINT_OOT_MODULE 12 433 434 extern const char hex_asc[]; 435 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 436 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 437 438 static inline char *hex_byte_pack(char *buf, u8 byte) 439 { 440 *buf++ = hex_asc_hi(byte); 441 *buf++ = hex_asc_lo(byte); 442 return buf; 443 } 444 445 static inline char * __deprecated pack_hex_byte(char *buf, u8 byte) 446 { 447 return hex_byte_pack(buf, byte); 448 } 449 450 extern int hex_to_bin(char ch); 451 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); 452 453 /* 454 * General tracing related utility functions - trace_printk(), 455 * tracing_on/tracing_off and tracing_start()/tracing_stop 456 * 457 * Use tracing_on/tracing_off when you want to quickly turn on or off 458 * tracing. It simply enables or disables the recording of the trace events. 459 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 460 * file, which gives a means for the kernel and userspace to interact. 461 * Place a tracing_off() in the kernel where you want tracing to end. 462 * From user space, examine the trace, and then echo 1 > tracing_on 463 * to continue tracing. 464 * 465 * tracing_stop/tracing_start has slightly more overhead. It is used 466 * by things like suspend to ram where disabling the recording of the 467 * trace is not enough, but tracing must actually stop because things 468 * like calling smp_processor_id() may crash the system. 469 * 470 * Most likely, you want to use tracing_on/tracing_off. 471 */ 472 #ifdef CONFIG_RING_BUFFER 473 /* trace_off_permanent stops recording with no way to bring it back */ 474 void tracing_off_permanent(void); 475 #else 476 static inline void tracing_off_permanent(void) { } 477 #endif 478 479 enum ftrace_dump_mode { 480 DUMP_NONE, 481 DUMP_ALL, 482 DUMP_ORIG, 483 }; 484 485 #ifdef CONFIG_TRACING 486 void tracing_on(void); 487 void tracing_off(void); 488 int tracing_is_on(void); 489 void tracing_snapshot(void); 490 void tracing_snapshot_alloc(void); 491 492 extern void tracing_start(void); 493 extern void tracing_stop(void); 494 extern void ftrace_off_permanent(void); 495 496 static inline __printf(1, 2) 497 void ____trace_printk_check_format(const char *fmt, ...) 498 { 499 } 500 #define __trace_printk_check_format(fmt, args...) \ 501 do { \ 502 if (0) \ 503 ____trace_printk_check_format(fmt, ##args); \ 504 } while (0) 505 506 /** 507 * trace_printk - printf formatting in the ftrace buffer 508 * @fmt: the printf format for printing 509 * 510 * Note: __trace_printk is an internal function for trace_printk and 511 * the @ip is passed in via the trace_printk macro. 512 * 513 * This function allows a kernel developer to debug fast path sections 514 * that printk is not appropriate for. By scattering in various 515 * printk like tracing in the code, a developer can quickly see 516 * where problems are occurring. 517 * 518 * This is intended as a debugging tool for the developer only. 519 * Please refrain from leaving trace_printks scattered around in 520 * your code. (Extra memory is used for special buffers that are 521 * allocated when trace_printk() is used) 522 * 523 * A little optization trick is done here. If there's only one 524 * argument, there's no need to scan the string for printf formats. 525 * The trace_puts() will suffice. But how can we take advantage of 526 * using trace_puts() when trace_printk() has only one argument? 527 * By stringifying the args and checking the size we can tell 528 * whether or not there are args. __stringify((__VA_ARGS__)) will 529 * turn into "()\0" with a size of 3 when there are no args, anything 530 * else will be bigger. All we need to do is define a string to this, 531 * and then take its size and compare to 3. If it's bigger, use 532 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just 533 * let gcc optimize the rest. 534 */ 535 536 #define trace_printk(fmt, ...) \ 537 do { \ 538 char _______STR[] = __stringify((__VA_ARGS__)); \ 539 if (sizeof(_______STR) > 3) \ 540 do_trace_printk(fmt, ##__VA_ARGS__); \ 541 else \ 542 trace_puts(fmt); \ 543 } while (0) 544 545 #define do_trace_printk(fmt, args...) \ 546 do { \ 547 static const char *trace_printk_fmt \ 548 __attribute__((section("__trace_printk_fmt"))) = \ 549 __builtin_constant_p(fmt) ? fmt : NULL; \ 550 \ 551 __trace_printk_check_format(fmt, ##args); \ 552 \ 553 if (__builtin_constant_p(fmt)) \ 554 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 555 else \ 556 __trace_printk(_THIS_IP_, fmt, ##args); \ 557 } while (0) 558 559 extern __printf(2, 3) 560 int __trace_bprintk(unsigned long ip, const char *fmt, ...); 561 562 extern __printf(2, 3) 563 int __trace_printk(unsigned long ip, const char *fmt, ...); 564 565 /** 566 * trace_puts - write a string into the ftrace buffer 567 * @str: the string to record 568 * 569 * Note: __trace_bputs is an internal function for trace_puts and 570 * the @ip is passed in via the trace_puts macro. 571 * 572 * This is similar to trace_printk() but is made for those really fast 573 * paths that a developer wants the least amount of "Heisenbug" affects, 574 * where the processing of the print format is still too much. 575 * 576 * This function allows a kernel developer to debug fast path sections 577 * that printk is not appropriate for. By scattering in various 578 * printk like tracing in the code, a developer can quickly see 579 * where problems are occurring. 580 * 581 * This is intended as a debugging tool for the developer only. 582 * Please refrain from leaving trace_puts scattered around in 583 * your code. (Extra memory is used for special buffers that are 584 * allocated when trace_puts() is used) 585 * 586 * Returns: 0 if nothing was written, positive # if string was. 587 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) 588 */ 589 590 extern int __trace_bputs(unsigned long ip, const char *str); 591 extern int __trace_puts(unsigned long ip, const char *str, int size); 592 #define trace_puts(str) ({ \ 593 static const char *trace_printk_fmt \ 594 __attribute__((section("__trace_printk_fmt"))) = \ 595 __builtin_constant_p(str) ? str : NULL; \ 596 \ 597 if (__builtin_constant_p(str)) \ 598 __trace_bputs(_THIS_IP_, trace_printk_fmt); \ 599 else \ 600 __trace_puts(_THIS_IP_, str, strlen(str)); \ 601 }) 602 603 extern void trace_dump_stack(int skip); 604 605 /* 606 * The double __builtin_constant_p is because gcc will give us an error 607 * if we try to allocate the static variable to fmt if it is not a 608 * constant. Even with the outer if statement. 609 */ 610 #define ftrace_vprintk(fmt, vargs) \ 611 do { \ 612 if (__builtin_constant_p(fmt)) { \ 613 static const char *trace_printk_fmt \ 614 __attribute__((section("__trace_printk_fmt"))) = \ 615 __builtin_constant_p(fmt) ? fmt : NULL; \ 616 \ 617 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 618 } else \ 619 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 620 } while (0) 621 622 extern int 623 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 624 625 extern int 626 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 627 628 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 629 #else 630 static inline void tracing_start(void) { } 631 static inline void tracing_stop(void) { } 632 static inline void ftrace_off_permanent(void) { } 633 static inline void trace_dump_stack(void) { } 634 635 static inline void tracing_on(void) { } 636 static inline void tracing_off(void) { } 637 static inline int tracing_is_on(void) { return 0; } 638 static inline void tracing_snapshot(void) { } 639 static inline void tracing_snapshot_alloc(void) { } 640 641 static inline __printf(1, 2) 642 int trace_printk(const char *fmt, ...) 643 { 644 return 0; 645 } 646 static inline int 647 ftrace_vprintk(const char *fmt, va_list ap) 648 { 649 return 0; 650 } 651 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 652 #endif /* CONFIG_TRACING */ 653 654 /* 655 * min()/max()/clamp() macros that also do 656 * strict type-checking.. See the 657 * "unnecessary" pointer comparison. 658 */ 659 #define min(x, y) ({ \ 660 typeof(x) _min1 = (x); \ 661 typeof(y) _min2 = (y); \ 662 (void) (&_min1 == &_min2); \ 663 _min1 < _min2 ? _min1 : _min2; }) 664 665 #define max(x, y) ({ \ 666 typeof(x) _max1 = (x); \ 667 typeof(y) _max2 = (y); \ 668 (void) (&_max1 == &_max2); \ 669 _max1 > _max2 ? _max1 : _max2; }) 670 671 #define min3(x, y, z) ({ \ 672 typeof(x) _min1 = (x); \ 673 typeof(y) _min2 = (y); \ 674 typeof(z) _min3 = (z); \ 675 (void) (&_min1 == &_min2); \ 676 (void) (&_min1 == &_min3); \ 677 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \ 678 (_min2 < _min3 ? _min2 : _min3); }) 679 680 #define max3(x, y, z) ({ \ 681 typeof(x) _max1 = (x); \ 682 typeof(y) _max2 = (y); \ 683 typeof(z) _max3 = (z); \ 684 (void) (&_max1 == &_max2); \ 685 (void) (&_max1 == &_max3); \ 686 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \ 687 (_max2 > _max3 ? _max2 : _max3); }) 688 689 /** 690 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 691 * @x: value1 692 * @y: value2 693 */ 694 #define min_not_zero(x, y) ({ \ 695 typeof(x) __x = (x); \ 696 typeof(y) __y = (y); \ 697 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 698 699 /** 700 * clamp - return a value clamped to a given range with strict typechecking 701 * @val: current value 702 * @min: minimum allowable value 703 * @max: maximum allowable value 704 * 705 * This macro does strict typechecking of min/max to make sure they are of the 706 * same type as val. See the unnecessary pointer comparisons. 707 */ 708 #define clamp(val, min, max) ({ \ 709 typeof(val) __val = (val); \ 710 typeof(min) __min = (min); \ 711 typeof(max) __max = (max); \ 712 (void) (&__val == &__min); \ 713 (void) (&__val == &__max); \ 714 __val = __val < __min ? __min: __val; \ 715 __val > __max ? __max: __val; }) 716 717 /* 718 * ..and if you can't take the strict 719 * types, you can specify one yourself. 720 * 721 * Or not use min/max/clamp at all, of course. 722 */ 723 #define min_t(type, x, y) ({ \ 724 type __min1 = (x); \ 725 type __min2 = (y); \ 726 __min1 < __min2 ? __min1: __min2; }) 727 728 #define max_t(type, x, y) ({ \ 729 type __max1 = (x); \ 730 type __max2 = (y); \ 731 __max1 > __max2 ? __max1: __max2; }) 732 733 /** 734 * clamp_t - return a value clamped to a given range using a given type 735 * @type: the type of variable to use 736 * @val: current value 737 * @min: minimum allowable value 738 * @max: maximum allowable value 739 * 740 * This macro does no typechecking and uses temporary variables of type 741 * 'type' to make all the comparisons. 742 */ 743 #define clamp_t(type, val, min, max) ({ \ 744 type __val = (val); \ 745 type __min = (min); \ 746 type __max = (max); \ 747 __val = __val < __min ? __min: __val; \ 748 __val > __max ? __max: __val; }) 749 750 /** 751 * clamp_val - return a value clamped to a given range using val's type 752 * @val: current value 753 * @min: minimum allowable value 754 * @max: maximum allowable value 755 * 756 * This macro does no typechecking and uses temporary variables of whatever 757 * type the input argument 'val' is. This is useful when val is an unsigned 758 * type and min and max are literals that will otherwise be assigned a signed 759 * integer type. 760 */ 761 #define clamp_val(val, min, max) ({ \ 762 typeof(val) __val = (val); \ 763 typeof(val) __min = (min); \ 764 typeof(val) __max = (max); \ 765 __val = __val < __min ? __min: __val; \ 766 __val > __max ? __max: __val; }) 767 768 769 /* 770 * swap - swap value of @a and @b 771 */ 772 #define swap(a, b) \ 773 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 774 775 /** 776 * container_of - cast a member of a structure out to the containing structure 777 * @ptr: the pointer to the member. 778 * @type: the type of the container struct this is embedded in. 779 * @member: the name of the member within the struct. 780 * 781 */ 782 #define container_of(ptr, type, member) ({ \ 783 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 784 (type *)( (char *)__mptr - offsetof(type,member) );}) 785 786 /* Trap pasters of __FUNCTION__ at compile-time */ 787 #define __FUNCTION__ (__func__) 788 789 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 790 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 791 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 792 #endif 793 794 #endif 795