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 #if defined(CONFIG_MMU) && \ 197 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)) 198 void might_fault(void); 199 #else 200 static inline void might_fault(void) { } 201 #endif 202 203 extern struct atomic_notifier_head panic_notifier_list; 204 extern long (*panic_blink)(int state); 205 __printf(1, 2) 206 void panic(const char *fmt, ...) 207 __noreturn __cold; 208 extern void oops_enter(void); 209 extern void oops_exit(void); 210 void print_oops_end_marker(void); 211 extern int oops_may_print(void); 212 void do_exit(long error_code) 213 __noreturn; 214 void complete_and_exit(struct completion *, long) 215 __noreturn; 216 217 /* Internal, do not use. */ 218 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 219 int __must_check _kstrtol(const char *s, unsigned int base, long *res); 220 221 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 222 int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 223 224 /** 225 * kstrtoul - convert a string to an unsigned long 226 * @s: The start of the string. The string must be null-terminated, and may also 227 * include a single newline before its terminating null. The first character 228 * may also be a plus sign, but not a minus sign. 229 * @base: The number base to use. The maximum supported base is 16. If base is 230 * given as 0, then the base of the string is automatically detected with the 231 * conventional semantics - If it begins with 0x the number will be parsed as a 232 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 233 * parsed as an octal number. Otherwise it will be parsed as a decimal. 234 * @res: Where to write the result of the conversion on success. 235 * 236 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 237 * Used as a replacement for the obsolete simple_strtoull. Return code must 238 * be checked. 239 */ 240 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) 241 { 242 /* 243 * We want to shortcut function call, but 244 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. 245 */ 246 if (sizeof(unsigned long) == sizeof(unsigned long long) && 247 __alignof__(unsigned long) == __alignof__(unsigned long long)) 248 return kstrtoull(s, base, (unsigned long long *)res); 249 else 250 return _kstrtoul(s, base, res); 251 } 252 253 /** 254 * kstrtol - convert a string to a long 255 * @s: The start of the string. The string must be null-terminated, and may also 256 * include a single newline before its terminating null. The first character 257 * may also be a plus sign or a minus sign. 258 * @base: The number base to use. The maximum supported base is 16. If base is 259 * given as 0, then the base of the string is automatically detected with the 260 * conventional semantics - If it begins with 0x the number will be parsed as a 261 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 262 * parsed as an octal number. Otherwise it will be parsed as a decimal. 263 * @res: Where to write the result of the conversion on success. 264 * 265 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 266 * Used as a replacement for the obsolete simple_strtoull. Return code must 267 * be checked. 268 */ 269 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) 270 { 271 /* 272 * We want to shortcut function call, but 273 * __builtin_types_compatible_p(long, long long) = 0. 274 */ 275 if (sizeof(long) == sizeof(long long) && 276 __alignof__(long) == __alignof__(long long)) 277 return kstrtoll(s, base, (long long *)res); 278 else 279 return _kstrtol(s, base, res); 280 } 281 282 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 283 int __must_check kstrtoint(const char *s, unsigned int base, int *res); 284 285 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 286 { 287 return kstrtoull(s, base, res); 288 } 289 290 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 291 { 292 return kstrtoll(s, base, res); 293 } 294 295 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 296 { 297 return kstrtouint(s, base, res); 298 } 299 300 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 301 { 302 return kstrtoint(s, base, res); 303 } 304 305 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 306 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 307 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 308 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 309 310 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 311 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 312 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 313 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 314 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 315 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 316 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 317 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 318 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 319 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 320 321 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) 322 { 323 return kstrtoull_from_user(s, count, base, res); 324 } 325 326 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) 327 { 328 return kstrtoll_from_user(s, count, base, res); 329 } 330 331 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) 332 { 333 return kstrtouint_from_user(s, count, base, res); 334 } 335 336 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) 337 { 338 return kstrtoint_from_user(s, count, base, res); 339 } 340 341 /* Obsolete, do not use. Use kstrto<foo> instead */ 342 343 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 344 extern long simple_strtol(const char *,char **,unsigned int); 345 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 346 extern long long simple_strtoll(const char *,char **,unsigned int); 347 #define strict_strtoul kstrtoul 348 #define strict_strtol kstrtol 349 #define strict_strtoull kstrtoull 350 #define strict_strtoll kstrtoll 351 352 extern int num_to_str(char *buf, int size, unsigned long long num); 353 354 /* lib/printf utilities */ 355 356 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 357 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 358 extern __printf(3, 4) 359 int snprintf(char *buf, size_t size, const char *fmt, ...); 360 extern __printf(3, 0) 361 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 362 extern __printf(3, 4) 363 int scnprintf(char *buf, size_t size, const char *fmt, ...); 364 extern __printf(3, 0) 365 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 366 extern __printf(2, 3) 367 char *kasprintf(gfp_t gfp, const char *fmt, ...); 368 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 369 370 extern __scanf(2, 3) 371 int sscanf(const char *, const char *, ...); 372 extern __scanf(2, 0) 373 int vsscanf(const char *, const char *, va_list); 374 375 extern int get_option(char **str, int *pint); 376 extern char *get_options(const char *str, int nints, int *ints); 377 extern unsigned long long memparse(const char *ptr, char **retptr); 378 379 extern int core_kernel_text(unsigned long addr); 380 extern int core_kernel_data(unsigned long addr); 381 extern int __kernel_text_address(unsigned long addr); 382 extern int kernel_text_address(unsigned long addr); 383 extern int func_ptr_is_kernel_text(void *ptr); 384 385 struct pid; 386 extern struct pid *session_of_pgrp(struct pid *pgrp); 387 388 unsigned long int_sqrt(unsigned long); 389 390 extern void bust_spinlocks(int yes); 391 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 392 extern int panic_timeout; 393 extern int panic_on_oops; 394 extern int panic_on_unrecovered_nmi; 395 extern int panic_on_io_nmi; 396 extern int sysctl_panic_on_stackoverflow; 397 /* 398 * Only to be used by arch init code. If the user over-wrote the default 399 * CONFIG_PANIC_TIMEOUT, honor it. 400 */ 401 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) 402 { 403 if (panic_timeout == arch_default_timeout) 404 panic_timeout = timeout; 405 } 406 extern const char *print_tainted(void); 407 enum lockdep_ok { 408 LOCKDEP_STILL_OK, 409 LOCKDEP_NOW_UNRELIABLE 410 }; 411 extern void add_taint(unsigned flag, enum lockdep_ok); 412 extern int test_taint(unsigned flag); 413 extern unsigned long get_taint(void); 414 extern int root_mountflags; 415 416 extern bool early_boot_irqs_disabled; 417 418 /* Values used for system_state */ 419 extern enum system_states { 420 SYSTEM_BOOTING, 421 SYSTEM_RUNNING, 422 SYSTEM_HALT, 423 SYSTEM_POWER_OFF, 424 SYSTEM_RESTART, 425 } system_state; 426 427 #define TAINT_PROPRIETARY_MODULE 0 428 #define TAINT_FORCED_MODULE 1 429 #define TAINT_UNSAFE_SMP 2 430 #define TAINT_FORCED_RMMOD 3 431 #define TAINT_MACHINE_CHECK 4 432 #define TAINT_BAD_PAGE 5 433 #define TAINT_USER 6 434 #define TAINT_DIE 7 435 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 436 #define TAINT_WARN 9 437 #define TAINT_CRAP 10 438 #define TAINT_FIRMWARE_WORKAROUND 11 439 #define TAINT_OOT_MODULE 12 440 441 extern const char hex_asc[]; 442 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 443 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 444 445 static inline char *hex_byte_pack(char *buf, u8 byte) 446 { 447 *buf++ = hex_asc_hi(byte); 448 *buf++ = hex_asc_lo(byte); 449 return buf; 450 } 451 452 extern const char hex_asc_upper[]; 453 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)] 454 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4] 455 456 static inline char *hex_byte_pack_upper(char *buf, u8 byte) 457 { 458 *buf++ = hex_asc_upper_hi(byte); 459 *buf++ = hex_asc_upper_lo(byte); 460 return buf; 461 } 462 463 static inline char * __deprecated pack_hex_byte(char *buf, u8 byte) 464 { 465 return hex_byte_pack(buf, byte); 466 } 467 468 extern int hex_to_bin(char ch); 469 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); 470 471 int mac_pton(const char *s, u8 *mac); 472 473 /* 474 * General tracing related utility functions - trace_printk(), 475 * tracing_on/tracing_off and tracing_start()/tracing_stop 476 * 477 * Use tracing_on/tracing_off when you want to quickly turn on or off 478 * tracing. It simply enables or disables the recording of the trace events. 479 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 480 * file, which gives a means for the kernel and userspace to interact. 481 * Place a tracing_off() in the kernel where you want tracing to end. 482 * From user space, examine the trace, and then echo 1 > tracing_on 483 * to continue tracing. 484 * 485 * tracing_stop/tracing_start has slightly more overhead. It is used 486 * by things like suspend to ram where disabling the recording of the 487 * trace is not enough, but tracing must actually stop because things 488 * like calling smp_processor_id() may crash the system. 489 * 490 * Most likely, you want to use tracing_on/tracing_off. 491 */ 492 #ifdef CONFIG_RING_BUFFER 493 /* trace_off_permanent stops recording with no way to bring it back */ 494 void tracing_off_permanent(void); 495 #else 496 static inline void tracing_off_permanent(void) { } 497 #endif 498 499 enum ftrace_dump_mode { 500 DUMP_NONE, 501 DUMP_ALL, 502 DUMP_ORIG, 503 }; 504 505 #ifdef CONFIG_TRACING 506 void tracing_on(void); 507 void tracing_off(void); 508 int tracing_is_on(void); 509 void tracing_snapshot(void); 510 void tracing_snapshot_alloc(void); 511 512 extern void tracing_start(void); 513 extern void tracing_stop(void); 514 515 static inline __printf(1, 2) 516 void ____trace_printk_check_format(const char *fmt, ...) 517 { 518 } 519 #define __trace_printk_check_format(fmt, args...) \ 520 do { \ 521 if (0) \ 522 ____trace_printk_check_format(fmt, ##args); \ 523 } while (0) 524 525 /** 526 * trace_printk - printf formatting in the ftrace buffer 527 * @fmt: the printf format for printing 528 * 529 * Note: __trace_printk is an internal function for trace_printk and 530 * the @ip is passed in via the trace_printk macro. 531 * 532 * This function allows a kernel developer to debug fast path sections 533 * that printk is not appropriate for. By scattering in various 534 * printk like tracing in the code, a developer can quickly see 535 * where problems are occurring. 536 * 537 * This is intended as a debugging tool for the developer only. 538 * Please refrain from leaving trace_printks scattered around in 539 * your code. (Extra memory is used for special buffers that are 540 * allocated when trace_printk() is used) 541 * 542 * A little optization trick is done here. If there's only one 543 * argument, there's no need to scan the string for printf formats. 544 * The trace_puts() will suffice. But how can we take advantage of 545 * using trace_puts() when trace_printk() has only one argument? 546 * By stringifying the args and checking the size we can tell 547 * whether or not there are args. __stringify((__VA_ARGS__)) will 548 * turn into "()\0" with a size of 3 when there are no args, anything 549 * else will be bigger. All we need to do is define a string to this, 550 * and then take its size and compare to 3. If it's bigger, use 551 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just 552 * let gcc optimize the rest. 553 */ 554 555 #define trace_printk(fmt, ...) \ 556 do { \ 557 char _______STR[] = __stringify((__VA_ARGS__)); \ 558 if (sizeof(_______STR) > 3) \ 559 do_trace_printk(fmt, ##__VA_ARGS__); \ 560 else \ 561 trace_puts(fmt); \ 562 } while (0) 563 564 #define do_trace_printk(fmt, args...) \ 565 do { \ 566 static const char *trace_printk_fmt \ 567 __attribute__((section("__trace_printk_fmt"))) = \ 568 __builtin_constant_p(fmt) ? fmt : NULL; \ 569 \ 570 __trace_printk_check_format(fmt, ##args); \ 571 \ 572 if (__builtin_constant_p(fmt)) \ 573 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 574 else \ 575 __trace_printk(_THIS_IP_, fmt, ##args); \ 576 } while (0) 577 578 extern __printf(2, 3) 579 int __trace_bprintk(unsigned long ip, const char *fmt, ...); 580 581 extern __printf(2, 3) 582 int __trace_printk(unsigned long ip, const char *fmt, ...); 583 584 /** 585 * trace_puts - write a string into the ftrace buffer 586 * @str: the string to record 587 * 588 * Note: __trace_bputs is an internal function for trace_puts and 589 * the @ip is passed in via the trace_puts macro. 590 * 591 * This is similar to trace_printk() but is made for those really fast 592 * paths that a developer wants the least amount of "Heisenbug" affects, 593 * where the processing of the print format is still too much. 594 * 595 * This function allows a kernel developer to debug fast path sections 596 * that printk is not appropriate for. By scattering in various 597 * printk like tracing in the code, a developer can quickly see 598 * where problems are occurring. 599 * 600 * This is intended as a debugging tool for the developer only. 601 * Please refrain from leaving trace_puts scattered around in 602 * your code. (Extra memory is used for special buffers that are 603 * allocated when trace_puts() is used) 604 * 605 * Returns: 0 if nothing was written, positive # if string was. 606 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) 607 */ 608 609 #define trace_puts(str) ({ \ 610 static const char *trace_printk_fmt \ 611 __attribute__((section("__trace_printk_fmt"))) = \ 612 __builtin_constant_p(str) ? str : NULL; \ 613 \ 614 if (__builtin_constant_p(str)) \ 615 __trace_bputs(_THIS_IP_, trace_printk_fmt); \ 616 else \ 617 __trace_puts(_THIS_IP_, str, strlen(str)); \ 618 }) 619 extern int __trace_bputs(unsigned long ip, const char *str); 620 extern int __trace_puts(unsigned long ip, const char *str, int size); 621 622 extern void trace_dump_stack(int skip); 623 624 /* 625 * The double __builtin_constant_p is because gcc will give us an error 626 * if we try to allocate the static variable to fmt if it is not a 627 * constant. Even with the outer if statement. 628 */ 629 #define ftrace_vprintk(fmt, vargs) \ 630 do { \ 631 if (__builtin_constant_p(fmt)) { \ 632 static const char *trace_printk_fmt \ 633 __attribute__((section("__trace_printk_fmt"))) = \ 634 __builtin_constant_p(fmt) ? fmt : NULL; \ 635 \ 636 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 637 } else \ 638 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 639 } while (0) 640 641 extern int 642 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 643 644 extern int 645 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 646 647 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 648 #else 649 static inline void tracing_start(void) { } 650 static inline void tracing_stop(void) { } 651 static inline void trace_dump_stack(int skip) { } 652 653 static inline void tracing_on(void) { } 654 static inline void tracing_off(void) { } 655 static inline int tracing_is_on(void) { return 0; } 656 static inline void tracing_snapshot(void) { } 657 static inline void tracing_snapshot_alloc(void) { } 658 659 static inline __printf(1, 2) 660 int trace_printk(const char *fmt, ...) 661 { 662 return 0; 663 } 664 static inline int 665 ftrace_vprintk(const char *fmt, va_list ap) 666 { 667 return 0; 668 } 669 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 670 #endif /* CONFIG_TRACING */ 671 672 /* 673 * min()/max()/clamp() macros that also do 674 * strict type-checking.. See the 675 * "unnecessary" pointer comparison. 676 */ 677 #define min(x, y) ({ \ 678 typeof(x) _min1 = (x); \ 679 typeof(y) _min2 = (y); \ 680 (void) (&_min1 == &_min2); \ 681 _min1 < _min2 ? _min1 : _min2; }) 682 683 #define max(x, y) ({ \ 684 typeof(x) _max1 = (x); \ 685 typeof(y) _max2 = (y); \ 686 (void) (&_max1 == &_max2); \ 687 _max1 > _max2 ? _max1 : _max2; }) 688 689 #define min3(x, y, z) ({ \ 690 typeof(x) _min1 = (x); \ 691 typeof(y) _min2 = (y); \ 692 typeof(z) _min3 = (z); \ 693 (void) (&_min1 == &_min2); \ 694 (void) (&_min1 == &_min3); \ 695 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \ 696 (_min2 < _min3 ? _min2 : _min3); }) 697 698 #define max3(x, y, z) ({ \ 699 typeof(x) _max1 = (x); \ 700 typeof(y) _max2 = (y); \ 701 typeof(z) _max3 = (z); \ 702 (void) (&_max1 == &_max2); \ 703 (void) (&_max1 == &_max3); \ 704 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \ 705 (_max2 > _max3 ? _max2 : _max3); }) 706 707 /** 708 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 709 * @x: value1 710 * @y: value2 711 */ 712 #define min_not_zero(x, y) ({ \ 713 typeof(x) __x = (x); \ 714 typeof(y) __y = (y); \ 715 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 716 717 /** 718 * clamp - return a value clamped to a given range with strict typechecking 719 * @val: current value 720 * @min: minimum allowable value 721 * @max: maximum allowable value 722 * 723 * This macro does strict typechecking of min/max to make sure they are of the 724 * same type as val. See the unnecessary pointer comparisons. 725 */ 726 #define clamp(val, min, max) ({ \ 727 typeof(val) __val = (val); \ 728 typeof(min) __min = (min); \ 729 typeof(max) __max = (max); \ 730 (void) (&__val == &__min); \ 731 (void) (&__val == &__max); \ 732 __val = __val < __min ? __min: __val; \ 733 __val > __max ? __max: __val; }) 734 735 /* 736 * ..and if you can't take the strict 737 * types, you can specify one yourself. 738 * 739 * Or not use min/max/clamp at all, of course. 740 */ 741 #define min_t(type, x, y) ({ \ 742 type __min1 = (x); \ 743 type __min2 = (y); \ 744 __min1 < __min2 ? __min1: __min2; }) 745 746 #define max_t(type, x, y) ({ \ 747 type __max1 = (x); \ 748 type __max2 = (y); \ 749 __max1 > __max2 ? __max1: __max2; }) 750 751 /** 752 * clamp_t - return a value clamped to a given range using a given type 753 * @type: the type of variable to use 754 * @val: current value 755 * @min: minimum allowable value 756 * @max: maximum allowable value 757 * 758 * This macro does no typechecking and uses temporary variables of type 759 * 'type' to make all the comparisons. 760 */ 761 #define clamp_t(type, val, min, max) ({ \ 762 type __val = (val); \ 763 type __min = (min); \ 764 type __max = (max); \ 765 __val = __val < __min ? __min: __val; \ 766 __val > __max ? __max: __val; }) 767 768 /** 769 * clamp_val - return a value clamped to a given range using val's type 770 * @val: current value 771 * @min: minimum allowable value 772 * @max: maximum allowable value 773 * 774 * This macro does no typechecking and uses temporary variables of whatever 775 * type the input argument 'val' is. This is useful when val is an unsigned 776 * type and min and max are literals that will otherwise be assigned a signed 777 * integer type. 778 */ 779 #define clamp_val(val, min, max) ({ \ 780 typeof(val) __val = (val); \ 781 typeof(val) __min = (min); \ 782 typeof(val) __max = (max); \ 783 __val = __val < __min ? __min: __val; \ 784 __val > __max ? __max: __val; }) 785 786 787 /* 788 * swap - swap value of @a and @b 789 */ 790 #define swap(a, b) \ 791 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 792 793 /** 794 * container_of - cast a member of a structure out to the containing structure 795 * @ptr: the pointer to the member. 796 * @type: the type of the container struct this is embedded in. 797 * @member: the name of the member within the struct. 798 * 799 */ 800 #define container_of(ptr, type, member) ({ \ 801 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 802 (type *)( (char *)__mptr - offsetof(type,member) );}) 803 804 /* Trap pasters of __FUNCTION__ at compile-time */ 805 #define __FUNCTION__ (__func__) 806 807 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 808 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 809 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 810 #endif 811 812 #endif 813