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 U8_MAX ((u8)~0U) 33#define S8_MAX ((s8)(U8_MAX>>1)) 34#define S8_MIN ((s8)(-S8_MAX - 1)) 35#define U16_MAX ((u16)~0U) 36#define S16_MAX ((s16)(U16_MAX>>1)) 37#define S16_MIN ((s16)(-S16_MAX - 1)) 38#define U32_MAX ((u32)~0U) 39#define S32_MAX ((s32)(U32_MAX>>1)) 40#define S32_MIN ((s32)(-S32_MAX - 1)) 41#define U64_MAX ((u64)~0ULL) 42#define S64_MAX ((s64)(U64_MAX>>1)) 43#define S64_MIN ((s64)(-S64_MAX - 1)) 44 45#define STACK_MAGIC 0xdeadbeef 46 47#define REPEAT_BYTE(x) ((~0ul / 0xff) * (x)) 48 49#define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) 50#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) 51#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) 52#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) 53 54#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) 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#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 64#define round_down(x, y) ((x) & ~__round_mask(x, y)) 65 66#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 67#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) 68#define DIV_ROUND_UP_ULL(ll,d) \ 69 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; }) 70 71#if BITS_PER_LONG == 32 72# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) 73#else 74# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) 75#endif 76 77/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */ 78#define roundup(x, y) ( \ 79{ \ 80 const typeof(y) __y = y; \ 81 (((x) + (__y - 1)) / __y) * __y; \ 82} \ 83) 84#define rounddown(x, y) ( \ 85{ \ 86 typeof(x) __x = (x); \ 87 __x - (__x % (y)); \ 88} \ 89) 90 91/* 92 * Divide positive or negative dividend by positive divisor and round 93 * to closest integer. Result is undefined for negative divisors and 94 * for negative dividends if the divisor variable type is unsigned. 95 */ 96#define DIV_ROUND_CLOSEST(x, divisor)( \ 97{ \ 98 typeof(x) __x = x; \ 99 typeof(divisor) __d = divisor; \ 100 (((typeof(x))-1) > 0 || \ 101 ((typeof(divisor))-1) > 0 || (__x) > 0) ? \ 102 (((__x) + ((__d) / 2)) / (__d)) : \ 103 (((__x) - ((__d) / 2)) / (__d)); \ 104} \ 105) 106/* 107 * Same as above but for u64 dividends. divisor must be a 32-bit 108 * number. 109 */ 110#define DIV_ROUND_CLOSEST_ULL(x, divisor)( \ 111{ \ 112 typeof(divisor) __d = divisor; \ 113 unsigned long long _tmp = (x) + (__d) / 2; \ 114 do_div(_tmp, __d); \ 115 _tmp; \ 116} \ 117) 118 119/* 120 * Multiplies an integer by a fraction, while avoiding unnecessary 121 * overflow or loss of precision. 122 */ 123#define mult_frac(x, numer, denom)( \ 124{ \ 125 typeof(x) quot = (x) / (denom); \ 126 typeof(x) rem = (x) % (denom); \ 127 (quot * (numer)) + ((rem * (numer)) / (denom)); \ 128} \ 129) 130 131 132#define _RET_IP_ (unsigned long)__builtin_return_address(0) 133#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 134 135#ifdef CONFIG_LBDAF 136# include <asm/div64.h> 137# define sector_div(a, b) do_div(a, b) 138#else 139# define sector_div(n, b)( \ 140{ \ 141 int _res; \ 142 _res = (n) % (b); \ 143 (n) /= (b); \ 144 _res; \ 145} \ 146) 147#endif 148 149/** 150 * upper_32_bits - return bits 32-63 of a number 151 * @n: the number we're accessing 152 * 153 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 154 * the "right shift count >= width of type" warning when that quantity is 155 * 32-bits. 156 */ 157#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 158 159/** 160 * lower_32_bits - return bits 0-31 of a number 161 * @n: the number we're accessing 162 */ 163#define lower_32_bits(n) ((u32)(n)) 164 165struct completion; 166struct pt_regs; 167struct user; 168 169#ifdef CONFIG_PREEMPT_VOLUNTARY 170extern int _cond_resched(void); 171# define might_resched() _cond_resched() 172#else 173# define might_resched() do { } while (0) 174#endif 175 176#ifdef CONFIG_DEBUG_ATOMIC_SLEEP 177 void ___might_sleep(const char *file, int line, int preempt_offset); 178 void __might_sleep(const char *file, int line, int preempt_offset); 179/** 180 * might_sleep - annotation for functions that can sleep 181 * 182 * this macro will print a stack trace if it is executed in an atomic 183 * context (spinlock, irq-handler, ...). 184 * 185 * This is a useful debugging help to be able to catch problems early and not 186 * be bitten later when the calling function happens to sleep when it is not 187 * supposed to. 188 */ 189# define might_sleep() \ 190 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 191# define sched_annotate_sleep() (current->task_state_change = 0) 192#else 193 static inline void ___might_sleep(const char *file, int line, 194 int preempt_offset) { } 195 static inline void __might_sleep(const char *file, int line, 196 int preempt_offset) { } 197# define might_sleep() do { might_resched(); } while (0) 198# define sched_annotate_sleep() do { } while (0) 199#endif 200 201#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 202 203/* 204 * abs() handles unsigned and signed longs, ints, shorts and chars. For all 205 * input types abs() returns a signed long. 206 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64() 207 * for those. 208 */ 209#define abs(x) ({ \ 210 long ret; \ 211 if (sizeof(x) == sizeof(long)) { \ 212 long __x = (x); \ 213 ret = (__x < 0) ? -__x : __x; \ 214 } else { \ 215 int __x = (x); \ 216 ret = (__x < 0) ? -__x : __x; \ 217 } \ 218 ret; \ 219 }) 220 221#define abs64(x) ({ \ 222 s64 __x = (x); \ 223 (__x < 0) ? -__x : __x; \ 224 }) 225 226/** 227 * reciprocal_scale - "scale" a value into range [0, ep_ro) 228 * @val: value 229 * @ep_ro: right open interval endpoint 230 * 231 * Perform a "reciprocal multiplication" in order to "scale" a value into 232 * range [0, ep_ro), where the upper interval endpoint is right-open. 233 * This is useful, e.g. for accessing a index of an array containing 234 * ep_ro elements, for example. Think of it as sort of modulus, only that 235 * the result isn't that of modulo. ;) Note that if initial input is a 236 * small value, then result will return 0. 237 * 238 * Return: a result based on val in interval [0, ep_ro). 239 */ 240static inline u32 reciprocal_scale(u32 val, u32 ep_ro) 241{ 242 return (u32)(((u64) val * ep_ro) >> 32); 243} 244 245#if defined(CONFIG_MMU) && \ 246 (defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_DEBUG_ATOMIC_SLEEP)) 247void might_fault(void); 248#else 249static inline void might_fault(void) { } 250#endif 251 252extern struct atomic_notifier_head panic_notifier_list; 253extern long (*panic_blink)(int state); 254__printf(1, 2) 255void panic(const char *fmt, ...) 256 __noreturn __cold; 257extern void oops_enter(void); 258extern void oops_exit(void); 259void print_oops_end_marker(void); 260extern int oops_may_print(void); 261void do_exit(long error_code) 262 __noreturn; 263void complete_and_exit(struct completion *, long) 264 __noreturn; 265 266/* Internal, do not use. */ 267int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 268int __must_check _kstrtol(const char *s, unsigned int base, long *res); 269 270int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 271int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 272 273/** 274 * kstrtoul - convert a string to an unsigned long 275 * @s: The start of the string. The string must be null-terminated, and may also 276 * include a single newline before its terminating null. The first character 277 * may also be a plus sign, but not a minus sign. 278 * @base: The number base to use. The maximum supported base is 16. If base is 279 * given as 0, then the base of the string is automatically detected with the 280 * conventional semantics - If it begins with 0x the number will be parsed as a 281 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 282 * parsed as an octal number. Otherwise it will be parsed as a decimal. 283 * @res: Where to write the result of the conversion on success. 284 * 285 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 286 * Used as a replacement for the obsolete simple_strtoull. Return code must 287 * be checked. 288*/ 289static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) 290{ 291 /* 292 * We want to shortcut function call, but 293 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. 294 */ 295 if (sizeof(unsigned long) == sizeof(unsigned long long) && 296 __alignof__(unsigned long) == __alignof__(unsigned long long)) 297 return kstrtoull(s, base, (unsigned long long *)res); 298 else 299 return _kstrtoul(s, base, res); 300} 301 302/** 303 * kstrtol - convert a string to a long 304 * @s: The start of the string. The string must be null-terminated, and may also 305 * include a single newline before its terminating null. The first character 306 * may also be a plus sign or a minus sign. 307 * @base: The number base to use. The maximum supported base is 16. If base is 308 * given as 0, then the base of the string is automatically detected with the 309 * conventional semantics - If it begins with 0x the number will be parsed as a 310 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be 311 * parsed as an octal number. Otherwise it will be parsed as a decimal. 312 * @res: Where to write the result of the conversion on success. 313 * 314 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error. 315 * Used as a replacement for the obsolete simple_strtoull. Return code must 316 * be checked. 317 */ 318static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) 319{ 320 /* 321 * We want to shortcut function call, but 322 * __builtin_types_compatible_p(long, long long) = 0. 323 */ 324 if (sizeof(long) == sizeof(long long) && 325 __alignof__(long) == __alignof__(long long)) 326 return kstrtoll(s, base, (long long *)res); 327 else 328 return _kstrtol(s, base, res); 329} 330 331int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 332int __must_check kstrtoint(const char *s, unsigned int base, int *res); 333 334static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 335{ 336 return kstrtoull(s, base, res); 337} 338 339static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 340{ 341 return kstrtoll(s, base, res); 342} 343 344static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 345{ 346 return kstrtouint(s, base, res); 347} 348 349static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 350{ 351 return kstrtoint(s, base, res); 352} 353 354int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 355int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 356int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 357int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 358 359int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 360int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 361int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 362int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 363int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 364int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 365int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 366int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 367int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 368int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 369 370static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) 371{ 372 return kstrtoull_from_user(s, count, base, res); 373} 374 375static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) 376{ 377 return kstrtoll_from_user(s, count, base, res); 378} 379 380static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) 381{ 382 return kstrtouint_from_user(s, count, base, res); 383} 384 385static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) 386{ 387 return kstrtoint_from_user(s, count, base, res); 388} 389 390/* Obsolete, do not use. Use kstrto<foo> instead */ 391 392extern unsigned long simple_strtoul(const char *,char **,unsigned int); 393extern long simple_strtol(const char *,char **,unsigned int); 394extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 395extern long long simple_strtoll(const char *,char **,unsigned int); 396 397extern int num_to_str(char *buf, int size, unsigned long long num); 398 399/* lib/printf utilities */ 400 401extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 402extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 403extern __printf(3, 4) 404int snprintf(char *buf, size_t size, const char *fmt, ...); 405extern __printf(3, 0) 406int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 407extern __printf(3, 4) 408int scnprintf(char *buf, size_t size, const char *fmt, ...); 409extern __printf(3, 0) 410int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 411extern __printf(2, 3) 412char *kasprintf(gfp_t gfp, const char *fmt, ...); 413extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 414 415extern __scanf(2, 3) 416int sscanf(const char *, const char *, ...); 417extern __scanf(2, 0) 418int vsscanf(const char *, const char *, va_list); 419 420extern int get_option(char **str, int *pint); 421extern char *get_options(const char *str, int nints, int *ints); 422extern unsigned long long memparse(const char *ptr, char **retptr); 423extern bool parse_option_str(const char *str, const char *option); 424 425extern int core_kernel_text(unsigned long addr); 426extern int core_kernel_data(unsigned long addr); 427extern int __kernel_text_address(unsigned long addr); 428extern int kernel_text_address(unsigned long addr); 429extern int func_ptr_is_kernel_text(void *ptr); 430 431unsigned long int_sqrt(unsigned long); 432 433extern void bust_spinlocks(int yes); 434extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 435extern int panic_timeout; 436extern int panic_on_oops; 437extern int panic_on_unrecovered_nmi; 438extern int panic_on_io_nmi; 439extern int panic_on_warn; 440extern int sysctl_panic_on_stackoverflow; 441/* 442 * Only to be used by arch init code. If the user over-wrote the default 443 * CONFIG_PANIC_TIMEOUT, honor it. 444 */ 445static inline void set_arch_panic_timeout(int timeout, int arch_default_timeout) 446{ 447 if (panic_timeout == arch_default_timeout) 448 panic_timeout = timeout; 449} 450extern const char *print_tainted(void); 451enum lockdep_ok { 452 LOCKDEP_STILL_OK, 453 LOCKDEP_NOW_UNRELIABLE 454}; 455extern void add_taint(unsigned flag, enum lockdep_ok); 456extern int test_taint(unsigned flag); 457extern unsigned long get_taint(void); 458extern int root_mountflags; 459 460extern bool early_boot_irqs_disabled; 461 462/* Values used for system_state */ 463extern enum system_states { 464 SYSTEM_BOOTING, 465 SYSTEM_RUNNING, 466 SYSTEM_HALT, 467 SYSTEM_POWER_OFF, 468 SYSTEM_RESTART, 469} system_state; 470 471#define TAINT_PROPRIETARY_MODULE 0 472#define TAINT_FORCED_MODULE 1 473#define TAINT_CPU_OUT_OF_SPEC 2 474#define TAINT_FORCED_RMMOD 3 475#define TAINT_MACHINE_CHECK 4 476#define TAINT_BAD_PAGE 5 477#define TAINT_USER 6 478#define TAINT_DIE 7 479#define TAINT_OVERRIDDEN_ACPI_TABLE 8 480#define TAINT_WARN 9 481#define TAINT_CRAP 10 482#define TAINT_FIRMWARE_WORKAROUND 11 483#define TAINT_OOT_MODULE 12 484#define TAINT_UNSIGNED_MODULE 13 485#define TAINT_SOFTLOCKUP 14 486#define TAINT_LIVEPATCH 15 487 488extern const char hex_asc[]; 489#define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 490#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 491 492static inline char *hex_byte_pack(char *buf, u8 byte) 493{ 494 *buf++ = hex_asc_hi(byte); 495 *buf++ = hex_asc_lo(byte); 496 return buf; 497} 498 499extern const char hex_asc_upper[]; 500#define hex_asc_upper_lo(x) hex_asc_upper[((x) & 0x0f)] 501#define hex_asc_upper_hi(x) hex_asc_upper[((x) & 0xf0) >> 4] 502 503static inline char *hex_byte_pack_upper(char *buf, u8 byte) 504{ 505 *buf++ = hex_asc_upper_hi(byte); 506 *buf++ = hex_asc_upper_lo(byte); 507 return buf; 508} 509 510extern int hex_to_bin(char ch); 511extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); 512extern char *bin2hex(char *dst, const void *src, size_t count); 513 514bool mac_pton(const char *s, u8 *mac); 515 516/* 517 * General tracing related utility functions - trace_printk(), 518 * tracing_on/tracing_off and tracing_start()/tracing_stop 519 * 520 * Use tracing_on/tracing_off when you want to quickly turn on or off 521 * tracing. It simply enables or disables the recording of the trace events. 522 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 523 * file, which gives a means for the kernel and userspace to interact. 524 * Place a tracing_off() in the kernel where you want tracing to end. 525 * From user space, examine the trace, and then echo 1 > tracing_on 526 * to continue tracing. 527 * 528 * tracing_stop/tracing_start has slightly more overhead. It is used 529 * by things like suspend to ram where disabling the recording of the 530 * trace is not enough, but tracing must actually stop because things 531 * like calling smp_processor_id() may crash the system. 532 * 533 * Most likely, you want to use tracing_on/tracing_off. 534 */ 535#ifdef CONFIG_RING_BUFFER 536/* trace_off_permanent stops recording with no way to bring it back */ 537void tracing_off_permanent(void); 538#else 539static inline void tracing_off_permanent(void) { } 540#endif 541 542enum ftrace_dump_mode { 543 DUMP_NONE, 544 DUMP_ALL, 545 DUMP_ORIG, 546}; 547 548#ifdef CONFIG_TRACING 549void tracing_on(void); 550void tracing_off(void); 551int tracing_is_on(void); 552void tracing_snapshot(void); 553void tracing_snapshot_alloc(void); 554 555extern void tracing_start(void); 556extern void tracing_stop(void); 557 558static inline __printf(1, 2) 559void ____trace_printk_check_format(const char *fmt, ...) 560{ 561} 562#define __trace_printk_check_format(fmt, args...) \ 563do { \ 564 if (0) \ 565 ____trace_printk_check_format(fmt, ##args); \ 566} while (0) 567 568/** 569 * trace_printk - printf formatting in the ftrace buffer 570 * @fmt: the printf format for printing 571 * 572 * Note: __trace_printk is an internal function for trace_printk and 573 * the @ip is passed in via the trace_printk macro. 574 * 575 * This function allows a kernel developer to debug fast path sections 576 * that printk is not appropriate for. By scattering in various 577 * printk like tracing in the code, a developer can quickly see 578 * where problems are occurring. 579 * 580 * This is intended as a debugging tool for the developer only. 581 * Please refrain from leaving trace_printks scattered around in 582 * your code. (Extra memory is used for special buffers that are 583 * allocated when trace_printk() is used) 584 * 585 * A little optization trick is done here. If there's only one 586 * argument, there's no need to scan the string for printf formats. 587 * The trace_puts() will suffice. But how can we take advantage of 588 * using trace_puts() when trace_printk() has only one argument? 589 * By stringifying the args and checking the size we can tell 590 * whether or not there are args. __stringify((__VA_ARGS__)) will 591 * turn into "()\0" with a size of 3 when there are no args, anything 592 * else will be bigger. All we need to do is define a string to this, 593 * and then take its size and compare to 3. If it's bigger, use 594 * do_trace_printk() otherwise, optimize it to trace_puts(). Then just 595 * let gcc optimize the rest. 596 */ 597 598#define trace_printk(fmt, ...) \ 599do { \ 600 char _______STR[] = __stringify((__VA_ARGS__)); \ 601 if (sizeof(_______STR) > 3) \ 602 do_trace_printk(fmt, ##__VA_ARGS__); \ 603 else \ 604 trace_puts(fmt); \ 605} while (0) 606 607#define do_trace_printk(fmt, args...) \ 608do { \ 609 static const char *trace_printk_fmt __used \ 610 __attribute__((section("__trace_printk_fmt"))) = \ 611 __builtin_constant_p(fmt) ? fmt : NULL; \ 612 \ 613 __trace_printk_check_format(fmt, ##args); \ 614 \ 615 if (__builtin_constant_p(fmt)) \ 616 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 617 else \ 618 __trace_printk(_THIS_IP_, fmt, ##args); \ 619} while (0) 620 621extern __printf(2, 3) 622int __trace_bprintk(unsigned long ip, const char *fmt, ...); 623 624extern __printf(2, 3) 625int __trace_printk(unsigned long ip, const char *fmt, ...); 626 627/** 628 * trace_puts - write a string into the ftrace buffer 629 * @str: the string to record 630 * 631 * Note: __trace_bputs is an internal function for trace_puts and 632 * the @ip is passed in via the trace_puts macro. 633 * 634 * This is similar to trace_printk() but is made for those really fast 635 * paths that a developer wants the least amount of "Heisenbug" affects, 636 * where the processing of the print format is still too much. 637 * 638 * This function allows a kernel developer to debug fast path sections 639 * that printk is not appropriate for. By scattering in various 640 * printk like tracing in the code, a developer can quickly see 641 * where problems are occurring. 642 * 643 * This is intended as a debugging tool for the developer only. 644 * Please refrain from leaving trace_puts scattered around in 645 * your code. (Extra memory is used for special buffers that are 646 * allocated when trace_puts() is used) 647 * 648 * Returns: 0 if nothing was written, positive # if string was. 649 * (1 when __trace_bputs is used, strlen(str) when __trace_puts is used) 650 */ 651 652#define trace_puts(str) ({ \ 653 static const char *trace_printk_fmt __used \ 654 __attribute__((section("__trace_printk_fmt"))) = \ 655 __builtin_constant_p(str) ? str : NULL; \ 656 \ 657 if (__builtin_constant_p(str)) \ 658 __trace_bputs(_THIS_IP_, trace_printk_fmt); \ 659 else \ 660 __trace_puts(_THIS_IP_, str, strlen(str)); \ 661}) 662extern int __trace_bputs(unsigned long ip, const char *str); 663extern int __trace_puts(unsigned long ip, const char *str, int size); 664 665extern void trace_dump_stack(int skip); 666 667/* 668 * The double __builtin_constant_p is because gcc will give us an error 669 * if we try to allocate the static variable to fmt if it is not a 670 * constant. Even with the outer if statement. 671 */ 672#define ftrace_vprintk(fmt, vargs) \ 673do { \ 674 if (__builtin_constant_p(fmt)) { \ 675 static const char *trace_printk_fmt __used \ 676 __attribute__((section("__trace_printk_fmt"))) = \ 677 __builtin_constant_p(fmt) ? fmt : NULL; \ 678 \ 679 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 680 } else \ 681 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 682} while (0) 683 684extern int 685__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 686 687extern int 688__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 689 690extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 691#else 692static inline void tracing_start(void) { } 693static inline void tracing_stop(void) { } 694static inline void trace_dump_stack(int skip) { } 695 696static inline void tracing_on(void) { } 697static inline void tracing_off(void) { } 698static inline int tracing_is_on(void) { return 0; } 699static inline void tracing_snapshot(void) { } 700static inline void tracing_snapshot_alloc(void) { } 701 702static inline __printf(1, 2) 703int trace_printk(const char *fmt, ...) 704{ 705 return 0; 706} 707static inline int 708ftrace_vprintk(const char *fmt, va_list ap) 709{ 710 return 0; 711} 712static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 713#endif /* CONFIG_TRACING */ 714 715/* 716 * min()/max()/clamp() macros that also do 717 * strict type-checking.. See the 718 * "unnecessary" pointer comparison. 719 */ 720#define min(x, y) ({ \ 721 typeof(x) _min1 = (x); \ 722 typeof(y) _min2 = (y); \ 723 (void) (&_min1 == &_min2); \ 724 _min1 < _min2 ? _min1 : _min2; }) 725 726#define max(x, y) ({ \ 727 typeof(x) _max1 = (x); \ 728 typeof(y) _max2 = (y); \ 729 (void) (&_max1 == &_max2); \ 730 _max1 > _max2 ? _max1 : _max2; }) 731 732#define min3(x, y, z) min((typeof(x))min(x, y), z) 733#define max3(x, y, z) max((typeof(x))max(x, y), z) 734 735/** 736 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 737 * @x: value1 738 * @y: value2 739 */ 740#define min_not_zero(x, y) ({ \ 741 typeof(x) __x = (x); \ 742 typeof(y) __y = (y); \ 743 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 744 745/** 746 * clamp - return a value clamped to a given range with strict typechecking 747 * @val: current value 748 * @lo: lowest allowable value 749 * @hi: highest allowable value 750 * 751 * This macro does strict typechecking of lo/hi to make sure they are of the 752 * same type as val. See the unnecessary pointer comparisons. 753 */ 754#define clamp(val, lo, hi) min((typeof(val))max(val, lo), hi) 755 756/* 757 * ..and if you can't take the strict 758 * types, you can specify one yourself. 759 * 760 * Or not use min/max/clamp at all, of course. 761 */ 762#define min_t(type, x, y) ({ \ 763 type __min1 = (x); \ 764 type __min2 = (y); \ 765 __min1 < __min2 ? __min1: __min2; }) 766 767#define max_t(type, x, y) ({ \ 768 type __max1 = (x); \ 769 type __max2 = (y); \ 770 __max1 > __max2 ? __max1: __max2; }) 771 772/** 773 * clamp_t - return a value clamped to a given range using a given type 774 * @type: the type of variable to use 775 * @val: current value 776 * @lo: minimum allowable value 777 * @hi: maximum allowable value 778 * 779 * This macro does no typechecking and uses temporary variables of type 780 * 'type' to make all the comparisons. 781 */ 782#define clamp_t(type, val, lo, hi) min_t(type, max_t(type, val, lo), hi) 783 784/** 785 * clamp_val - return a value clamped to a given range using val's type 786 * @val: current value 787 * @lo: minimum allowable value 788 * @hi: maximum allowable value 789 * 790 * This macro does no typechecking and uses temporary variables of whatever 791 * type the input argument 'val' is. This is useful when val is an unsigned 792 * type and min and max are literals that will otherwise be assigned a signed 793 * integer type. 794 */ 795#define clamp_val(val, lo, hi) clamp_t(typeof(val), val, lo, hi) 796 797 798/* 799 * swap - swap value of @a and @b 800 */ 801#define swap(a, b) \ 802 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 803 804/** 805 * container_of - cast a member of a structure out to the containing structure 806 * @ptr: the pointer to the member. 807 * @type: the type of the container struct this is embedded in. 808 * @member: the name of the member within the struct. 809 * 810 */ 811#define container_of(ptr, type, member) ({ \ 812 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 813 (type *)( (char *)__mptr - offsetof(type,member) );}) 814 815/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 816#ifdef CONFIG_FTRACE_MCOUNT_RECORD 817# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 818#endif 819 820/* Permissions on a sysfs file: you didn't miss the 0 prefix did you? */ 821#define VERIFY_OCTAL_PERMISSIONS(perms) \ 822 (BUILD_BUG_ON_ZERO((perms) < 0) + \ 823 BUILD_BUG_ON_ZERO((perms) > 0777) + \ 824 /* User perms >= group perms >= other perms */ \ 825 BUILD_BUG_ON_ZERO(((perms) >> 6) < (((perms) >> 3) & 7)) + \ 826 BUILD_BUG_ON_ZERO((((perms) >> 3) & 7) < ((perms) & 7)) + \ 827 /* Other writable? Generally considered a bad idea. */ \ 828 BUILD_BUG_ON_ZERO((perms) & 2) + \ 829 (perms)) 830#endif 831