1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_KERNEL_H 3 #define _LINUX_KERNEL_H 4 5 6 #include <stdarg.h> 7 #include <linux/limits.h> 8 #include <linux/linkage.h> 9 #include <linux/stddef.h> 10 #include <linux/types.h> 11 #include <linux/compiler.h> 12 #include <linux/bitops.h> 13 #include <linux/log2.h> 14 #include <linux/typecheck.h> 15 #include <linux/printk.h> 16 #include <linux/build_bug.h> 17 #include <asm/byteorder.h> 18 #include <asm/div64.h> 19 #include <uapi/linux/kernel.h> 20 #include <asm/div64.h> 21 22 #define STACK_MAGIC 0xdeadbeef 23 24 /** 25 * REPEAT_BYTE - repeat the value @x multiple times as an unsigned long value 26 * @x: value to repeat 27 * 28 * NOTE: @x is not checked for > 0xff; larger values produce odd results. 29 */ 30 #define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) 31 32 /* @a is a power of 2 value */ 33 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) 34 #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a)) 35 #define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) 36 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) 37 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) 38 39 /* generic data direction definitions */ 40 #define READ 0 41 #define WRITE 1 42 43 /** 44 * ARRAY_SIZE - get the number of elements in array @arr 45 * @arr: array to be sized 46 */ 47 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) 48 49 #define u64_to_user_ptr(x) ( \ 50 { \ 51 typecheck(u64, (x)); \ 52 (void __user *)(uintptr_t)(x); \ 53 } \ 54 ) 55 56 /* 57 * This looks more complex than it should be. But we need to 58 * get the type for the ~ right in round_down (it needs to be 59 * as wide as the result!), and we want to evaluate the macro 60 * arguments just once each. 61 */ 62 #define __round_mask(x, y) ((__typeof__(x))((y)-1)) 63 /** 64 * round_up - round up to next specified power of 2 65 * @x: the value to round 66 * @y: multiple to round up to (must be a power of 2) 67 * 68 * Rounds @x up to next multiple of @y (which must be a power of 2). 69 * To perform arbitrary rounding up, use roundup() below. 70 */ 71 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 72 /** 73 * round_down - round down to next specified power of 2 74 * @x: the value to round 75 * @y: multiple to round down to (must be a power of 2) 76 * 77 * Rounds @x down to next multiple of @y (which must be a power of 2). 78 * To perform arbitrary rounding down, use rounddown() below. 79 */ 80 #define round_down(x, y) ((x) & ~__round_mask(x, y)) 81 82 /** 83 * FIELD_SIZEOF - get the size of a struct's field 84 * @t: the target struct 85 * @f: the target struct's field 86 * Return: the size of @f in the struct definition without having a 87 * declared instance of @t. 88 */ 89 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 90 91 #define typeof_member(T, m) typeof(((T*)0)->m) 92 93 #define DIV_ROUND_UP __KERNEL_DIV_ROUND_UP 94 95 #define DIV_ROUND_DOWN_ULL(ll, d) \ 96 ({ unsigned long long _tmp = (ll); do_div(_tmp, d); _tmp; }) 97 98 #define DIV_ROUND_UP_ULL(ll, d) \ 99 DIV_ROUND_DOWN_ULL((unsigned long long)(ll) + (d) - 1, (d)) 100 101 #if BITS_PER_LONG == 32 102 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) 103 #else 104 # define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) 105 #endif 106 107 /** 108 * roundup - round up to the next specified multiple 109 * @x: the value to up 110 * @y: multiple to round up to 111 * 112 * Rounds @x up to next multiple of @y. If @y will always be a power 113 * of 2, consider using the faster round_up(). 114 */ 115 #define roundup(x, y) ( \ 116 { \ 117 typeof(y) __y = y; \ 118 (((x) + (__y - 1)) / __y) * __y; \ 119 } \ 120 ) 121 /** 122 * rounddown - round down to next specified multiple 123 * @x: the value to round 124 * @y: multiple to round down to 125 * 126 * Rounds @x down to next multiple of @y. If @y will always be a power 127 * of 2, consider using the faster round_down(). 128 */ 129 #define rounddown(x, y) ( \ 130 { \ 131 typeof(x) __x = (x); \ 132 __x - (__x % (y)); \ 133 } \ 134 ) 135 136 /* 137 * Divide positive or negative dividend by positive or negative divisor 138 * and round to closest integer. Result is undefined for negative 139 * divisors if the dividend variable type is unsigned and for negative 140 * dividends if the divisor variable type is unsigned. 141 */ 142 #define DIV_ROUND_CLOSEST(x, divisor)( \ 143 { \ 144 typeof(x) __x = x; \ 145 typeof(divisor) __d = divisor; \ 146 (((typeof(x))-1) > 0 || \ 147 ((typeof(divisor))-1) > 0 || \ 148 (((__x) > 0) == ((__d) > 0))) ? \ 149 (((__x) + ((__d) / 2)) / (__d)) : \ 150 (((__x) - ((__d) / 2)) / (__d)); \ 151 } \ 152 ) 153 /* 154 * Same as above but for u64 dividends. divisor must be a 32-bit 155 * number. 156 */ 157 #define DIV_ROUND_CLOSEST_ULL(x, divisor)( \ 158 { \ 159 typeof(divisor) __d = divisor; \ 160 unsigned long long _tmp = (x) + (__d) / 2; \ 161 do_div(_tmp, __d); \ 162 _tmp; \ 163 } \ 164 ) 165 166 /* 167 * Multiplies an integer by a fraction, while avoiding unnecessary 168 * overflow or loss of precision. 169 */ 170 #define mult_frac(x, numer, denom)( \ 171 { \ 172 typeof(x) quot = (x) / (denom); \ 173 typeof(x) rem = (x) % (denom); \ 174 (quot * (numer)) + ((rem * (numer)) / (denom)); \ 175 } \ 176 ) 177 178 179 #define _RET_IP_ (unsigned long)__builtin_return_address(0) 180 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 181 182 #define sector_div(a, b) do_div(a, b) 183 184 /** 185 * upper_32_bits - return bits 32-63 of a number 186 * @n: the number we're accessing 187 * 188 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 189 * the "right shift count >= width of type" warning when that quantity is 190 * 32-bits. 191 */ 192 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 193 194 /** 195 * lower_32_bits - return bits 0-31 of a number 196 * @n: the number we're accessing 197 */ 198 #define lower_32_bits(n) ((u32)(n)) 199 200 struct completion; 201 struct pt_regs; 202 struct user; 203 204 #ifdef CONFIG_PREEMPT_VOLUNTARY 205 extern int _cond_resched(void); 206 # define might_resched() _cond_resched() 207 #else 208 # define might_resched() do { } while (0) 209 #endif 210 211 #ifdef CONFIG_DEBUG_ATOMIC_SLEEP 212 extern void ___might_sleep(const char *file, int line, int preempt_offset); 213 extern void __might_sleep(const char *file, int line, int preempt_offset); 214 extern void __cant_sleep(const char *file, int line, int preempt_offset); 215 216 /** 217 * might_sleep - annotation for functions that can sleep 218 * 219 * this macro will print a stack trace if it is executed in an atomic 220 * context (spinlock, irq-handler, ...). Additional sections where blocking is 221 * not allowed can be annotated with non_block_start() and non_block_end() 222 * pairs. 223 * 224 * This is a useful debugging help to be able to catch problems early and not 225 * be bitten later when the calling function happens to sleep when it is not 226 * supposed to. 227 */ 228 # define might_sleep() \ 229 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 230 /** 231 * cant_sleep - annotation for functions that cannot sleep 232 * 233 * this macro will print a stack trace if it is executed with preemption enabled 234 */ 235 # define cant_sleep() \ 236 do { __cant_sleep(__FILE__, __LINE__, 0); } while (0) 237 # define sched_annotate_sleep() (current->task_state_change = 0) 238 /** 239 * non_block_start - annotate the start of section where sleeping is prohibited 240 * 241 * This is on behalf of the oom reaper, specifically when it is calling the mmu 242 * notifiers. The problem is that if the notifier were to block on, for example, 243 * mutex_lock() and if the process which holds that mutex were to perform a 244 * sleeping memory allocation, the oom reaper is now blocked on completion of 245 * that memory allocation. Other blocking calls like wait_event() pose similar 246 * issues. 247 */ 248 # define non_block_start() (current->non_block_count++) 249 /** 250 * non_block_end - annotate the end of section where sleeping is prohibited 251 * 252 * Closes a section opened by non_block_start(). 253 */ 254 # define non_block_end() WARN_ON(current->non_block_count-- == 0) 255 #else 256 static inline void ___might_sleep(const char *file, int line, 257 int preempt_offset) { } 258 static inline void __might_sleep(const char *file, int line, 259 int preempt_offset) { } 260 # define might_sleep() do { might_resched(); } while (0) 261 # define cant_sleep() do { } while (0) 262 # define sched_annotate_sleep() do { } while (0) 263 # define non_block_start() do { } while (0) 264 # define non_block_end() do { } while (0) 265 #endif 266 267 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 268 269 /** 270 * abs - return absolute value of an argument 271 * @x: the value. If it is unsigned type, it is converted to signed type first. 272 * char is treated as if it was signed (regardless of whether it really is) 273 * but the macro's return type is preserved as char. 274 * 275 * Return: an absolute value of x. 276 */ 277 #define abs(x) __abs_choose_expr(x, long long, \ 278 __abs_choose_expr(x, long, \ 279 __abs_choose_expr(x, int, \ 280 __abs_choose_expr(x, short, \ 281 __abs_choose_expr(x, char, \ 282 __builtin_choose_expr( \ 283 __builtin_types_compatible_p(typeof(x), char), \ 284 (char)({ signed char __x = (x); __x<0?-__x:__x; }), \ 285 ((void)0))))))) 286 287 #define __abs_choose_expr(x, type, other) __builtin_choose_expr( \ 288 __builtin_types_compatible_p(typeof(x), signed type) || \ 289 __builtin_types_compatible_p(typeof(x), unsigned type), \ 290 ({ signed type __x = (x); __x < 0 ? -__x : __x; }), other) 291 292 /** 293 * reciprocal_scale - "scale" a value into range [0, ep_ro) 294 * @val: value 295 * @ep_ro: right open interval endpoint 296 * 297 * Perform a "reciprocal multiplication" in order to "scale" a value into 298 * range [0, @ep_ro), where the upper interval endpoint is right-open. 299 * This is useful, e.g. for accessing a index of an array containing 300 * @ep_ro elements, for example. Think of it as sort of modulus, only that 301 * the result isn't that of modulo. ;) Note that if initial input is a 302 * small value, then result will return 0. 303 * 304 * Return: a result based on @val in interval [0, @ep_ro). 305 */ 306 static inline u32 reciprocal_scale(u32 val, u32 ep_ro) 307 { 308 return (u32)(((u64) val * ep_ro) >> 32); 309 } 310 311 #if defined(CONFIG_MMU) && \ 312 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)) 313 #define might_fault() __might_fault(__FILE__, __LINE__) 314 void __might_fault(const char *file, int line); 315 #else 316 static inline void might_fault(void) { } 317 #endif 318 319 extern struct atomic_notifier_head panic_notifier_list; 320 extern long (*panic_blink)(int state); 321 __printf(1, 2) 322 void panic(const char *fmt, ...) __noreturn __cold; 323 void nmi_panic(struct pt_regs *regs, const char *msg); 324 extern void oops_enter(void); 325 extern void oops_exit(void); 326 void print_oops_end_marker(void); 327 extern int oops_may_print(void); 328 void do_exit(long error_code) __noreturn; 329 void complete_and_exit(struct completion *, long) __noreturn; 330 331 #ifdef CONFIG_ARCH_HAS_REFCOUNT 332 void refcount_error_report(struct pt_regs *regs, const char *err); 333 #else 334 static inline void refcount_error_report(struct pt_regs *regs, const char *err) 335 { } 336 #endif 337 338 /* Internal, do not use. */ 339 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 340 int __must_check _kstrtol(const char *s, unsigned int base, long *res); 341 342 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 343 int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 344 345 /** 346 * kstrtoul - convert a string to an unsigned long 347 * @s: The start of the string. The string must be null-terminated, and may also 348 * include a single newline before its terminating null. The first character 349 * may also be a plus sign, but not a minus sign. 350 * @base: The number base to use. The maximum supported base is 16. If base is 351 * given as 0, then the base of the string is automatically detected with the 352 * conventional semantics - If it begins with 0x the number will be parsed as a 353 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 354 * parsed as an octal number. Otherwise it will be parsed as a decimal. 355 * @res: Where to write the result of the conversion on success. 356 * 357 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 358 * Used as a replacement for the obsolete simple_strtoull. Return code must 359 * be checked. 360 */ 361 static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) 362 { 363 /* 364 * We want to shortcut function call, but 365 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. 366 */ 367 if (sizeof(unsigned long) == sizeof(unsigned long long) && 368 __alignof__(unsigned long) == __alignof__(unsigned long long)) 369 return kstrtoull(s, base, (unsigned long long *)res); 370 else 371 return _kstrtoul(s, base, res); 372 } 373 374 /** 375 * kstrtol - convert a string to a long 376 * @s: The start of the string. The string must be null-terminated, and may also 377 * include a single newline before its terminating null. The first character 378 * may also be a plus sign or a minus sign. 379 * @base: The number base to use. The maximum supported base is 16. If base is 380 * given as 0, then the base of the string is automatically detected with the 381 * conventional semantics - If it begins with 0x the number will be parsed as a 382 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 383 * parsed as an octal number. Otherwise it will be parsed as a decimal. 384 * @res: Where to write the result of the conversion on success. 385 * 386 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 387 * Used as a replacement for the obsolete simple_strtoull. Return code must 388 * be checked. 389 */ 390 static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) 391 { 392 /* 393 * We want to shortcut function call, but 394 * __builtin_types_compatible_p(long, long long) = 0. 395 */ 396 if (sizeof(long) == sizeof(long long) && 397 __alignof__(long) == __alignof__(long long)) 398 return kstrtoll(s, base, (long long *)res); 399 else 400 return _kstrtol(s, base, res); 401 } 402 403 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 404 int __must_check kstrtoint(const char *s, unsigned int base, int *res); 405 406 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 407 { 408 return kstrtoull(s, base, res); 409 } 410 411 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 412 { 413 return kstrtoll(s, base, res); 414 } 415 416 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 417 { 418 return kstrtouint(s, base, res); 419 } 420 421 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 422 { 423 return kstrtoint(s, base, res); 424 } 425 426 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 427 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 428 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 429 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 430 int __must_check kstrtobool(const char *s, bool *res); 431 432 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 433 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 434 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 435 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 436 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 437 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 438 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 439 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 440 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 441 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 442 int __must_check kstrtobool_from_user(const char __user *s, size_t count, bool *res); 443 444 static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) 445 { 446 return kstrtoull_from_user(s, count, base, res); 447 } 448 449 static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) 450 { 451 return kstrtoll_from_user(s, count, base, res); 452 } 453 454 static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) 455 { 456 return kstrtouint_from_user(s, count, base, res); 457 } 458 459 static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) 460 { 461 return kstrtoint_from_user(s, count, base, res); 462 } 463 464 /* Obsolete, do not use. Use kstrto<foo> instead */ 465 466 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 467 extern long simple_strtol(const char *,char **,unsigned int); 468 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 469 extern long long simple_strtoll(const char *,char **,unsigned int); 470 471 extern int num_to_str(char *buf, int size, 472 unsigned long long num, unsigned int width); 473 474 /* lib/printf utilities */ 475 476 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 477 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 478 extern __printf(3, 4) 479 int snprintf(char *buf, size_t size, const char *fmt, ...); 480 extern __printf(3, 0) 481 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 482 extern __printf(3, 4) 483 int scnprintf(char *buf, size_t size, const char *fmt, ...); 484 extern __printf(3, 0) 485 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 486 extern __printf(2, 3) __malloc 487 char *kasprintf(gfp_t gfp, const char *fmt, ...); 488 extern __printf(2, 0) __malloc 489 char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 490 extern __printf(2, 0) 491 const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list args); 492 493 extern __scanf(2, 3) 494 int sscanf(const char *, const char *, ...); 495 extern __scanf(2, 0) 496 int vsscanf(const char *, const char *, va_list); 497 498 extern int get_option(char **str, int *pint); 499 extern char *get_options(const char *str, int nints, int *ints); 500 extern unsigned long long memparse(const char *ptr, char **retptr); 501 extern bool parse_option_str(const char *str, const char *option); 502 extern char *next_arg(char *args, char **param, char **val); 503 504 extern int core_kernel_text(unsigned long addr); 505 extern int init_kernel_text(unsigned long addr); 506 extern int core_kernel_data(unsigned long addr); 507 extern int __kernel_text_address(unsigned long addr); 508 extern int kernel_text_address(unsigned long addr); 509 extern int func_ptr_is_kernel_text(void *ptr); 510 511 u64 int_pow(u64 base, unsigned int exp); 512 unsigned long int_sqrt(unsigned long); 513 514 #if BITS_PER_LONG < 64 515 u32 int_sqrt64(u64 x); 516 #else 517 static inline u32 int_sqrt64(u64 x) 518 { 519 return (u32)int_sqrt(x); 520 } 521 #endif 522 523 extern void bust_spinlocks(int yes); 524 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 525 extern int panic_timeout; 526 extern unsigned long panic_print; 527 extern int panic_on_oops; 528 extern int panic_on_unrecovered_nmi; 529 extern int panic_on_io_nmi; 530 extern int panic_on_warn; 531 extern int sysctl_panic_on_rcu_stall; 532 extern int sysctl_panic_on_stackoverflow; 533 534 extern bool crash_kexec_post_notifiers; 535 536 /* 537 * panic_cpu is used for synchronizing panic() and crash_kexec() execution. It 538 * holds a CPU number which is executing panic() currently. A value of 539 * PANIC_CPU_INVALID means no CPU has entered panic() or crash_kexec(). 540 */ 541 extern atomic_t panic_cpu; 542 #define PANIC_CPU_INVALID -1 543 544 /* 545 * Only to be used by arch init code. If the user over-wrote the default 546 * CONFIG_PANIC_TIMEOUT, honor it. 547 */ 548 static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) 549 { 550 if (panic_timeout == arch_default_timeout) 551 panic_timeout = timeout; 552 } 553 extern const char *print_tainted(void); 554 enum lockdep_ok { 555 LOCKDEP_STILL_OK, 556 LOCKDEP_NOW_UNRELIABLE 557 }; 558 extern void add_taint(unsigned flag, enum lockdep_ok); 559 extern int test_taint(unsigned flag); 560 extern unsigned long get_taint(void); 561 extern int root_mountflags; 562 563 extern bool early_boot_irqs_disabled; 564 565 /* 566 * Values used for system_state. Ordering of the states must not be changed 567 * as code checks for <, <=, >, >= STATE. 568 */ 569 extern enum system_states { 570 SYSTEM_BOOTING, 571 SYSTEM_SCHEDULING, 572 SYSTEM_RUNNING, 573 SYSTEM_HALT, 574 SYSTEM_POWER_OFF, 575 SYSTEM_RESTART, 576 SYSTEM_SUSPEND, 577 } system_state; 578 579 /* This cannot be an enum because some may be used in assembly source. */ 580 #define TAINT_PROPRIETARY_MODULE 0 581 #define TAINT_FORCED_MODULE 1 582 #define TAINT_CPU_OUT_OF_SPEC 2 583 #define TAINT_FORCED_RMMOD 3 584 #define TAINT_MACHINE_CHECK 4 585 #define TAINT_BAD_PAGE 5 586 #define TAINT_USER 6 587 #define TAINT_DIE 7 588 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 589 #define TAINT_WARN 9 590 #define TAINT_CRAP 10 591 #define TAINT_FIRMWARE_WORKAROUND 11 592 #define TAINT_OOT_MODULE 12 593 #define TAINT_UNSIGNED_MODULE 13 594 #define TAINT_SOFTLOCKUP 14 595 #define TAINT_LIVEPATCH 15 596 #define TAINT_AUX 16 597 #define TAINT_RANDSTRUCT 17 598 #define TAINT_FLAGS_COUNT 18 599 600 struct taint_flag { 601 char c_true; /* character printed when tainted */ 602 char c_false; /* character printed when not tainted */ 603 bool module; /* also show as a per-module taint flag */ 604 }; 605 606 extern const struct taint_flag taint_flags[TAINT_FLAGS_COUNT]; 607 608 extern const char hex_asc[]; 609 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 610 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 611 612 static inline char *hex_byte_pack(char *buf, u8 byte) 613 { 614 *buf++ = hex_asc_hi(byte); 615 *buf++ = hex_asc_lo(byte); 616 return buf; 617 } 618 619 extern const char hex_asc_upper[]; 620 #define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)] 621 #define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4] 622 623 static inline char *hex_byte_pack_upper(char *buf, u8 byte) 624 { 625 *buf++ = hex_asc_upper_hi(byte); 626 *buf++ = hex_asc_upper_lo(byte); 627 return buf; 628 } 629 630 extern int hex_to_bin(char ch); 631 extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); 632 extern char *bin2hex(char *dst, const void *src, size_t count); 633 634 bool mac_pton(const char *s, u8 *mac); 635 636 /* 637 * General tracing related utility functions - trace_printk(), 638 * tracing_on/tracing_off and tracing_start()/tracing_stop 639 * 640 * Use tracing_on/tracing_off when you want to quickly turn on or off 641 * tracing. It simply enables or disables the recording of the trace events. 642 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 643 * file, which gives a means for the kernel and userspace to interact. 644 * Place a tracing_off() in the kernel where you want tracing to end. 645 * From user space, examine the trace, and then echo 1 > tracing_on 646 * to continue tracing. 647 * 648 * tracing_stop/tracing_start has slightly more overhead. It is used 649 * by things like suspend to ram where disabling the recording of the 650 * trace is not enough, but tracing must actually stop because things 651 * like calling smp_processor_id() may crash the system. 652 * 653 * Most likely, you want to use tracing_on/tracing_off. 654 */ 655 656 enum ftrace_dump_mode { 657 DUMP_NONE, 658 DUMP_ALL, 659 DUMP_ORIG, 660 }; 661 662 #ifdef CONFIG_TRACING 663 void tracing_on(void); 664 void tracing_off(void); 665 int tracing_is_on(void); 666 void tracing_snapshot(void); 667 void tracing_snapshot_alloc(void); 668 669 extern void tracing_start(void); 670 extern void tracing_stop(void); 671 672 static inline __printf(1, 2) 673 void ____trace_printk_check_format(const char *fmt, ...) 674 { 675 } 676 #define __trace_printk_check_format(fmt, args...) \ 677 do { \ 678 if (0) \ 679 ____trace_printk_check_format(fmt, ##args); \ 680 } while (0) 681 682 /** 683 * trace_printk - printf formatting in the ftrace buffer 684 * @fmt: the printf format for printing 685 * 686 * Note: __trace_printk is an internal function for trace_printk() and 687 * the @ip is passed in via the trace_printk() macro. 688 * 689 * This function allows a kernel developer to debug fast path sections 690 * that printk is not appropriate for. By scattering in various 691 * printk like tracing in the code, a developer can quickly see 692 * where problems are occurring. 693 * 694 * This is intended as a debugging tool for the developer only. 695 * Please refrain from leaving trace_printks scattered around in 696 * your code. (Extra memory is used for special buffers that are 697 * allocated when trace_printk() is used.) 698 * 699 * A little optimization trick is done here. If there's only one 700 * argument, there's no need to scan the string for printf formats. 701 * The trace_puts() will suffice. But how can we take advantage of 702 * using trace_puts() when trace_printk() has only one argument? 703 * By stringifying the args and checking the size we can tell 704 * whether or not there are args. __stringify((__VA_ARGS__)) will 705 * turn into "()\0" with a size of 3 when there are no args, anything 706 * else will be bigger. All we need to do is define a string to this, 707 * and then take its size and compare to 3. If it's bigger, use 708 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just 709 * let gcc optimize the rest. 710 */ 711 712 #define trace_printk(fmt, ...) \ 713 do { \ 714 char _______STR[] = __stringify((__VA_ARGS__)); \ 715 if (sizeof(_______STR) > 3) \ 716 do_trace_printk(fmt, ##__VA_ARGS__); \ 717 else \ 718 trace_puts(fmt); \ 719 } while (0) 720 721 #define do_trace_printk(fmt, args...) \ 722 do { \ 723 static const char *trace_printk_fmt __used \ 724 __attribute__((section("__trace_printk_fmt"))) = \ 725 __builtin_constant_p(fmt) ? fmt : NULL; \ 726 \ 727 __trace_printk_check_format(fmt, ##args); \ 728 \ 729 if (__builtin_constant_p(fmt)) \ 730 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 731 else \ 732 __trace_printk(_THIS_IP_, fmt, ##args); \ 733 } while (0) 734 735 extern __printf(2, 3) 736 int __trace_bprintk(unsigned long ip, const char *fmt, ...); 737 738 extern __printf(2, 3) 739 int __trace_printk(unsigned long ip, const char *fmt, ...); 740 741 /** 742 * trace_puts - write a string into the ftrace buffer 743 * @str: the string to record 744 * 745 * Note: __trace_bputs is an internal function for trace_puts and 746 * the @ip is passed in via the trace_puts macro. 747 * 748 * This is similar to trace_printk() but is made for those really fast 749 * paths that a developer wants the least amount of "Heisenbug" effects, 750 * where the processing of the print format is still too much. 751 * 752 * This function allows a kernel developer to debug fast path sections 753 * that printk is not appropriate for. By scattering in various 754 * printk like tracing in the code, a developer can quickly see 755 * where problems are occurring. 756 * 757 * This is intended as a debugging tool for the developer only. 758 * Please refrain from leaving trace_puts scattered around in 759 * your code. (Extra memory is used for special buffers that are 760 * allocated when trace_puts() is used.) 761 * 762 * Returns: 0 if nothing was written, positive # if string was. 763 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) 764 */ 765 766 #define trace_puts(str) ({ \ 767 static const char *trace_printk_fmt __used \ 768 __attribute__((section("__trace_printk_fmt"))) = \ 769 __builtin_constant_p(str) ? str : NULL; \ 770 \ 771 if (__builtin_constant_p(str)) \ 772 __trace_bputs(_THIS_IP_, trace_printk_fmt); \ 773 else \ 774 __trace_puts(_THIS_IP_, str, strlen(str)); \ 775 }) 776 extern int __trace_bputs(unsigned long ip, const char *str); 777 extern int __trace_puts(unsigned long ip, const char *str, int size); 778 779 extern void trace_dump_stack(int skip); 780 781 /* 782 * The double __builtin_constant_p is because gcc will give us an error 783 * if we try to allocate the static variable to fmt if it is not a 784 * constant. Even with the outer if statement. 785 */ 786 #define ftrace_vprintk(fmt, vargs) \ 787 do { \ 788 if (__builtin_constant_p(fmt)) { \ 789 static const char *trace_printk_fmt __used \ 790 __attribute__((section("__trace_printk_fmt"))) = \ 791 __builtin_constant_p(fmt) ? fmt : NULL; \ 792 \ 793 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 794 } else \ 795 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 796 } while (0) 797 798 extern __printf(2, 0) int 799 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 800 801 extern __printf(2, 0) int 802 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 803 804 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 805 #else 806 static inline void tracing_start(void) { } 807 static inline void tracing_stop(void) { } 808 static inline void trace_dump_stack(int skip) { } 809 810 static inline void tracing_on(void) { } 811 static inline void tracing_off(void) { } 812 static inline int tracing_is_on(void) { return 0; } 813 static inline void tracing_snapshot(void) { } 814 static inline void tracing_snapshot_alloc(void) { } 815 816 static inline __printf(1, 2) 817 int trace_printk(const char *fmt, ...) 818 { 819 return 0; 820 } 821 static __printf(1, 0) inline int 822 ftrace_vprintk(const char *fmt, va_list ap) 823 { 824 return 0; 825 } 826 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 827 #endif /* CONFIG_TRACING */ 828 829 /* 830 * min()/max()/clamp() macros must accomplish three things: 831 * 832 * - avoid multiple evaluations of the arguments (so side-effects like 833 * "x++" happen only once) when non-constant. 834 * - perform strict type-checking (to generate warnings instead of 835 * nasty runtime surprises). See the "unnecessary" pointer comparison 836 * in __typecheck(). 837 * - retain result as a constant expressions when called with only 838 * constant expressions (to avoid tripping VLA warnings in stack 839 * allocation usage). 840 */ 841 #define __typecheck(x, y) \ 842 (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) 843 844 /* 845 * This returns a constant expression while determining if an argument is 846 * a constant expression, most importantly without evaluating the argument. 847 * Glory to Martin Uecker <Martin.Uecker@med.uni-goettingen.de> 848 */ 849 #define __is_constexpr(x) \ 850 (sizeof(int) == sizeof(*(8 ? ((void *)((long)(x) * 0l)) : (int *)8))) 851 852 #define __no_side_effects(x, y) \ 853 (__is_constexpr(x) && __is_constexpr(y)) 854 855 #define __safe_cmp(x, y) \ 856 (__typecheck(x, y) && __no_side_effects(x, y)) 857 858 #define __cmp(x, y, op) ((x) op (y) ? (x) : (y)) 859 860 #define __cmp_once(x, y, unique_x, unique_y, op) ({ \ 861 typeof(x) unique_x = (x); \ 862 typeof(y) unique_y = (y); \ 863 __cmp(unique_x, unique_y, op); }) 864 865 #define __careful_cmp(x, y, op) \ 866 __builtin_choose_expr(__safe_cmp(x, y), \ 867 __cmp(x, y, op), \ 868 __cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op)) 869 870 /** 871 * min - return minimum of two values of the same or compatible types 872 * @x: first value 873 * @y: second value 874 */ 875 #define min(x, y) __careful_cmp(x, y, <) 876 877 /** 878 * max - return maximum of two values of the same or compatible types 879 * @x: first value 880 * @y: second value 881 */ 882 #define max(x, y) __careful_cmp(x, y, >) 883 884 /** 885 * min3 - return minimum of three values 886 * @x: first value 887 * @y: second value 888 * @z: third value 889 */ 890 #define min3(x, y, z) min((typeof(x))min(x, y), z) 891 892 /** 893 * max3 - return maximum of three values 894 * @x: first value 895 * @y: second value 896 * @z: third value 897 */ 898 #define max3(x, y, z) max((typeof(x))max(x, y), z) 899 900 /** 901 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 902 * @x: value1 903 * @y: value2 904 */ 905 #define min_not_zero(x, y) ({ \ 906 typeof(x) __x = (x); \ 907 typeof(y) __y = (y); \ 908 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 909 910 /** 911 * clamp - return a value clamped to a given range with strict typechecking 912 * @val: current value 913 * @lo: lowest allowable value 914 * @hi: highest allowable value 915 * 916 * This macro does strict typechecking of @lo/@hi to make sure they are of the 917 * same type as @val. See the unnecessary pointer comparisons. 918 */ 919 #define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi) 920 921 /* 922 * ..and if you can't take the strict 923 * types, you can specify one yourself. 924 * 925 * Or not use min/max/clamp at all, of course. 926 */ 927 928 /** 929 * min_t - return minimum of two values, using the specified type 930 * @type: data type to use 931 * @x: first value 932 * @y: second value 933 */ 934 #define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <) 935 936 /** 937 * max_t - return maximum of two values, using the specified type 938 * @type: data type to use 939 * @x: first value 940 * @y: second value 941 */ 942 #define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >) 943 944 /** 945 * clamp_t - return a value clamped to a given range using a given type 946 * @type: the type of variable to use 947 * @val: current value 948 * @lo: minimum allowable value 949 * @hi: maximum allowable value 950 * 951 * This macro does no typechecking and uses temporary variables of type 952 * @type to make all the comparisons. 953 */ 954 #define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi) 955 956 /** 957 * clamp_val - return a value clamped to a given range using val's type 958 * @val: current value 959 * @lo: minimum allowable value 960 * @hi: maximum allowable value 961 * 962 * This macro does no typechecking and uses temporary variables of whatever 963 * type the input argument @val is. This is useful when @val is an unsigned 964 * type and @lo and @hi are literals that will otherwise be assigned a signed 965 * integer type. 966 */ 967 #define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) 968 969 970 /** 971 * swap - swap values of @a and @b 972 * @a: first value 973 * @b: second value 974 */ 975 #define swap(a, b) \ 976 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 977 978 /* This counts to 12. Any more, it will return 13th argument. */ 979 #define __COUNT_ARGS(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _n, X...) _n 980 #define COUNT_ARGS(X...) __COUNT_ARGS(, ##X, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) 981 982 #define __CONCAT(a, b) a ## b 983 #define CONCATENATE(a, b) __CONCAT(a, b) 984 985 /** 986 * container_of - cast a member of a structure out to the containing structure 987 * @ptr: the pointer to the member. 988 * @type: the type of the container struct this is embedded in. 989 * @member: the name of the member within the struct. 990 * 991 */ 992 #define container_of(ptr, type, member) ({ \ 993 void *__mptr = (void *)(ptr); \ 994 BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ 995 !__same_type(*(ptr), void), \ 996 "pointer type mismatch in container_of()"); \ 997 ((type *)(__mptr - offsetof(type, member))); }) 998 999 /** 1000 * container_of_safe - cast a member of a structure out to the containing structure 1001 * @ptr: the pointer to the member. 1002 * @type: the type of the container struct this is embedded in. 1003 * @member: the name of the member within the struct. 1004 * 1005 * If IS_ERR_OR_NULL(ptr), ptr is returned unchanged. 1006 */ 1007 #define container_of_safe(ptr, type, member) ({ \ 1008 void *__mptr = (void *)(ptr); \ 1009 BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ 1010 !__same_type(*(ptr), void), \ 1011 "pointer type mismatch in container_of()"); \ 1012 IS_ERR_OR_NULL(__mptr) ? ERR_CAST(__mptr) : \ 1013 ((type *)(__mptr - offsetof(type, member))); }) 1014 1015 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 1016 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 1017 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 1018 #endif 1019 1020 /* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */ 1021 #define VERIFY_OCTAL_PERMISSIONS(perms) \ 1022 (BUILD_BUG_ON_ZERO((perms) < 0) + \ 1023 BUILD_BUG_ON_ZERO((perms) > 0777) + \ 1024 /* USER_READABLE >= GROUP_READABLE >= OTHER_READABLE */ \ 1025 BUILD_BUG_ON_ZERO((((perms) >> 6) & 4) < (((perms) >> 3) & 4)) + \ 1026 BUILD_BUG_ON_ZERO((((perms) >> 3) & 4) < ((perms) & 4)) + \ 1027 /* USER_WRITABLE >= GROUP_WRITABLE */ \ 1028 BUILD_BUG_ON_ZERO((((perms) >> 6) & 2) < (((perms) >> 3) & 2)) + \ 1029 /* OTHER_WRITABLE? Generally considered a bad idea. */ \ 1030 BUILD_BUG_ON_ZERO((perms) & 2) + \ 1031 (perms)) 1032 #endif 1033