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