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1#ifndef _LINUX_KERNEL_H 2#define _LINUX_KERNEL_H 3 4/* 5 * 'kernel.h' contains some often-used function prototypes etc 6 */ 7#define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1) 8#define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask)) 9 10#ifdef __KERNEL__ 11 12#include <stdarg.h> 13#include <linux/linkage.h> 14#include <linux/stddef.h> 15#include <linux/types.h> 16#include <linux/compiler.h> 17#include <linux/bitops.h> 18#include <linux/log2.h> 19#include <linux/typecheck.h> 20#include <linux/printk.h> 21#include <linux/dynamic_debug.h> 22#include <asm/byteorder.h> 23#include <asm/bug.h> 24 25#define USHRT_MAX ((u16)(~0U)) 26#define SHRT_MAX ((s16)(USHRT_MAX>>1)) 27#define SHRT_MIN ((s16)(-SHRT_MAX - 1)) 28#define INT_MAX ((int)(~0U>>1)) 29#define INT_MIN (-INT_MAX - 1) 30#define UINT_MAX (~0U) 31#define LONG_MAX ((long)(~0UL>>1)) 32#define LONG_MIN (-LONG_MAX - 1) 33#define ULONG_MAX (~0UL) 34#define LLONG_MAX ((long long)(~0ULL>>1)) 35#define LLONG_MIN (-LLONG_MAX - 1) 36#define ULLONG_MAX (~0ULL) 37 38#define STACK_MAGIC 0xdeadbeef 39 40#define ALIGN(x, a) __ALIGN_KERNEL((x), (a)) 41#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (mask)) 42#define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) 43#define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) 44 45#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) 46 47/* 48 * This looks more complex than it should be. But we need to 49 * get the type for the ~ right in round_down (it needs to be 50 * as wide as the result!), and we want to evaluate the macro 51 * arguments just once each. 52 */ 53#define __round_mask(x, y) ((__typeof__(x))((y)-1)) 54#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1) 55#define round_down(x, y) ((x) & ~__round_mask(x, y)) 56 57#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 58#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) 59#define DIV_ROUND_UP_ULL(ll,d) \ 60 ({ unsigned long long _tmp = (ll)+(d)-1; do_div(_tmp, d); _tmp; }) 61 62#if BITS_PER_LONG == 32 63# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP_ULL(ll, d) 64#else 65# define DIV_ROUND_UP_SECTOR_T(ll,d) DIV_ROUND_UP(ll,d) 66#endif 67 68/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */ 69#define roundup(x, y) ( \ 70{ \ 71 const typeof(y) __y = y; \ 72 (((x) + (__y - 1)) / __y) * __y; \ 73} \ 74) 75#define rounddown(x, y) ( \ 76{ \ 77 typeof(x) __x = (x); \ 78 __x - (__x % (y)); \ 79} \ 80) 81#define DIV_ROUND_CLOSEST(x, divisor)( \ 82{ \ 83 typeof(divisor) __divisor = divisor; \ 84 (((x) + ((__divisor) / 2)) / (__divisor)); \ 85} \ 86) 87 88#define _RET_IP_ (unsigned long)__builtin_return_address(0) 89#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 90 91#ifdef CONFIG_LBDAF 92# include <asm/div64.h> 93# define sector_div(a, b) do_div(a, b) 94#else 95# define sector_div(n, b)( \ 96{ \ 97 int _res; \ 98 _res = (n) % (b); \ 99 (n) /= (b); \ 100 _res; \ 101} \ 102) 103#endif 104 105/** 106 * upper_32_bits - return bits 32-63 of a number 107 * @n: the number we're accessing 108 * 109 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 110 * the "right shift count >= width of type" warning when that quantity is 111 * 32-bits. 112 */ 113#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 114 115/** 116 * lower_32_bits - return bits 0-31 of a number 117 * @n: the number we're accessing 118 */ 119#define lower_32_bits(n) ((u32)(n)) 120 121struct completion; 122struct pt_regs; 123struct user; 124 125#ifdef CONFIG_PREEMPT_VOLUNTARY 126extern int _cond_resched(void); 127# define might_resched() _cond_resched() 128#else 129# define might_resched() do { } while (0) 130#endif 131 132#ifdef CONFIG_DEBUG_ATOMIC_SLEEP 133 void __might_sleep(const char *file, int line, int preempt_offset); 134/** 135 * might_sleep - annotation for functions that can sleep 136 * 137 * this macro will print a stack trace if it is executed in an atomic 138 * context (spinlock, irq-handler, ...). 139 * 140 * This is a useful debugging help to be able to catch problems early and not 141 * be bitten later when the calling function happens to sleep when it is not 142 * supposed to. 143 */ 144# define might_sleep() \ 145 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 146#else 147 static inline void __might_sleep(const char *file, int line, 148 int preempt_offset) { } 149# define might_sleep() do { might_resched(); } while (0) 150#endif 151 152#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 153 154/* 155 * abs() handles unsigned and signed longs, ints, shorts and chars. For all 156 * input types abs() returns a signed long. 157 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64() 158 * for those. 159 */ 160#define abs(x) ({ \ 161 long ret; \ 162 if (sizeof(x) == sizeof(long)) { \ 163 long __x = (x); \ 164 ret = (__x < 0) ? -__x : __x; \ 165 } else { \ 166 int __x = (x); \ 167 ret = (__x < 0) ? -__x : __x; \ 168 } \ 169 ret; \ 170 }) 171 172#define abs64(x) ({ \ 173 s64 __x = (x); \ 174 (__x < 0) ? -__x : __x; \ 175 }) 176 177#ifdef CONFIG_PROVE_LOCKING 178void might_fault(void); 179#else 180static inline void might_fault(void) 181{ 182 might_sleep(); 183} 184#endif 185 186extern struct atomic_notifier_head panic_notifier_list; 187extern long (*panic_blink)(int state); 188__printf(1, 2) 189void panic(const char *fmt, ...) 190 __noreturn __cold; 191extern void oops_enter(void); 192extern void oops_exit(void); 193void print_oops_end_marker(void); 194extern int oops_may_print(void); 195void do_exit(long error_code) 196 __noreturn; 197void complete_and_exit(struct completion *, long) 198 __noreturn; 199 200/* Internal, do not use. */ 201int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 202int __must_check _kstrtol(const char *s, unsigned int base, long *res); 203 204int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 205int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 206static inline int __must_check kstrtoul(const char *s, unsigned int base, unsigned long *res) 207{ 208 /* 209 * We want to shortcut function call, but 210 * __builtin_types_compatible_p(unsigned long, unsigned long long) = 0. 211 */ 212 if (sizeof(unsigned long) == sizeof(unsigned long long) && 213 __alignof__(unsigned long) == __alignof__(unsigned long long)) 214 return kstrtoull(s, base, (unsigned long long *)res); 215 else 216 return _kstrtoul(s, base, res); 217} 218 219static inline int __must_check kstrtol(const char *s, unsigned int base, long *res) 220{ 221 /* 222 * We want to shortcut function call, but 223 * __builtin_types_compatible_p(long, long long) = 0. 224 */ 225 if (sizeof(long) == sizeof(long long) && 226 __alignof__(long) == __alignof__(long long)) 227 return kstrtoll(s, base, (long long *)res); 228 else 229 return _kstrtol(s, base, res); 230} 231 232int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 233int __must_check kstrtoint(const char *s, unsigned int base, int *res); 234 235static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 236{ 237 return kstrtoull(s, base, res); 238} 239 240static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 241{ 242 return kstrtoll(s, base, res); 243} 244 245static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 246{ 247 return kstrtouint(s, base, res); 248} 249 250static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 251{ 252 return kstrtoint(s, base, res); 253} 254 255int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 256int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 257int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 258int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 259 260int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 261int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 262int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 263int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 264int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 265int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 266int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 267int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 268int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 269int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 270 271static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res) 272{ 273 return kstrtoull_from_user(s, count, base, res); 274} 275 276static inline int __must_check kstrtos64_from_user(const char __user *s, size_t count, unsigned int base, s64 *res) 277{ 278 return kstrtoll_from_user(s, count, base, res); 279} 280 281static inline int __must_check kstrtou32_from_user(const char __user *s, size_t count, unsigned int base, u32 *res) 282{ 283 return kstrtouint_from_user(s, count, base, res); 284} 285 286static inline int __must_check kstrtos32_from_user(const char __user *s, size_t count, unsigned int base, s32 *res) 287{ 288 return kstrtoint_from_user(s, count, base, res); 289} 290 291/* Obsolete, do not use. Use kstrto<foo> instead */ 292 293extern unsigned long simple_strtoul(const char *,char **,unsigned int); 294extern long simple_strtol(const char *,char **,unsigned int); 295extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 296extern long long simple_strtoll(const char *,char **,unsigned int); 297#define strict_strtoul kstrtoul 298#define strict_strtol kstrtol 299#define strict_strtoull kstrtoull 300#define strict_strtoll kstrtoll 301 302/* lib/printf utilities */ 303 304extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 305extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 306extern __printf(3, 4) 307int snprintf(char *buf, size_t size, const char *fmt, ...); 308extern __printf(3, 0) 309int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 310extern __printf(3, 4) 311int scnprintf(char *buf, size_t size, const char *fmt, ...); 312extern __printf(3, 0) 313int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 314extern __printf(2, 3) 315char *kasprintf(gfp_t gfp, const char *fmt, ...); 316extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 317 318extern int sscanf(const char *, const char *, ...) 319 __attribute__ ((format (scanf, 2, 3))); 320extern int vsscanf(const char *, const char *, va_list) 321 __attribute__ ((format (scanf, 2, 0))); 322 323extern int get_option(char **str, int *pint); 324extern char *get_options(const char *str, int nints, int *ints); 325extern unsigned long long memparse(const char *ptr, char **retptr); 326 327extern int core_kernel_text(unsigned long addr); 328extern int core_kernel_data(unsigned long addr); 329extern int __kernel_text_address(unsigned long addr); 330extern int kernel_text_address(unsigned long addr); 331extern int func_ptr_is_kernel_text(void *ptr); 332 333struct pid; 334extern struct pid *session_of_pgrp(struct pid *pgrp); 335 336unsigned long int_sqrt(unsigned long); 337 338extern void bust_spinlocks(int yes); 339extern void wake_up_klogd(void); 340extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 341extern int panic_timeout; 342extern int panic_on_oops; 343extern int panic_on_unrecovered_nmi; 344extern int panic_on_io_nmi; 345extern int sysctl_panic_on_stackoverflow; 346extern const char *print_tainted(void); 347extern void add_taint(unsigned flag); 348extern int test_taint(unsigned flag); 349extern unsigned long get_taint(void); 350extern int root_mountflags; 351 352extern bool early_boot_irqs_disabled; 353 354/* Values used for system_state */ 355extern enum system_states { 356 SYSTEM_BOOTING, 357 SYSTEM_RUNNING, 358 SYSTEM_HALT, 359 SYSTEM_POWER_OFF, 360 SYSTEM_RESTART, 361 SYSTEM_SUSPEND_DISK, 362} system_state; 363 364#define TAINT_PROPRIETARY_MODULE 0 365#define TAINT_FORCED_MODULE 1 366#define TAINT_UNSAFE_SMP 2 367#define TAINT_FORCED_RMMOD 3 368#define TAINT_MACHINE_CHECK 4 369#define TAINT_BAD_PAGE 5 370#define TAINT_USER 6 371#define TAINT_DIE 7 372#define TAINT_OVERRIDDEN_ACPI_TABLE 8 373#define TAINT_WARN 9 374#define TAINT_CRAP 10 375#define TAINT_FIRMWARE_WORKAROUND 11 376#define TAINT_OOT_MODULE 12 377 378extern const char hex_asc[]; 379#define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 380#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 381 382static inline char *hex_byte_pack(char *buf, u8 byte) 383{ 384 *buf++ = hex_asc_hi(byte); 385 *buf++ = hex_asc_lo(byte); 386 return buf; 387} 388 389static inline char * __deprecated pack_hex_byte(char *buf, u8 byte) 390{ 391 return hex_byte_pack(buf, byte); 392} 393 394extern int hex_to_bin(char ch); 395extern int __must_check hex2bin(u8 *dst, const char *src, size_t count); 396 397/* 398 * General tracing related utility functions - trace_printk(), 399 * tracing_on/tracing_off and tracing_start()/tracing_stop 400 * 401 * Use tracing_on/tracing_off when you want to quickly turn on or off 402 * tracing. It simply enables or disables the recording of the trace events. 403 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 404 * file, which gives a means for the kernel and userspace to interact. 405 * Place a tracing_off() in the kernel where you want tracing to end. 406 * From user space, examine the trace, and then echo 1 > tracing_on 407 * to continue tracing. 408 * 409 * tracing_stop/tracing_start has slightly more overhead. It is used 410 * by things like suspend to ram where disabling the recording of the 411 * trace is not enough, but tracing must actually stop because things 412 * like calling smp_processor_id() may crash the system. 413 * 414 * Most likely, you want to use tracing_on/tracing_off. 415 */ 416#ifdef CONFIG_RING_BUFFER 417void tracing_on(void); 418void tracing_off(void); 419/* trace_off_permanent stops recording with no way to bring it back */ 420void tracing_off_permanent(void); 421int tracing_is_on(void); 422#else 423static inline void tracing_on(void) { } 424static inline void tracing_off(void) { } 425static inline void tracing_off_permanent(void) { } 426static inline int tracing_is_on(void) { return 0; } 427#endif 428 429enum ftrace_dump_mode { 430 DUMP_NONE, 431 DUMP_ALL, 432 DUMP_ORIG, 433}; 434 435#ifdef CONFIG_TRACING 436extern void tracing_start(void); 437extern void tracing_stop(void); 438extern void ftrace_off_permanent(void); 439 440static inline __printf(1, 2) 441void ____trace_printk_check_format(const char *fmt, ...) 442{ 443} 444#define __trace_printk_check_format(fmt, args...) \ 445do { \ 446 if (0) \ 447 ____trace_printk_check_format(fmt, ##args); \ 448} while (0) 449 450/** 451 * trace_printk - printf formatting in the ftrace buffer 452 * @fmt: the printf format for printing 453 * 454 * Note: __trace_printk is an internal function for trace_printk and 455 * the @ip is passed in via the trace_printk macro. 456 * 457 * This function allows a kernel developer to debug fast path sections 458 * that printk is not appropriate for. By scattering in various 459 * printk like tracing in the code, a developer can quickly see 460 * where problems are occurring. 461 * 462 * This is intended as a debugging tool for the developer only. 463 * Please refrain from leaving trace_printks scattered around in 464 * your code. 465 */ 466 467#define trace_printk(fmt, args...) \ 468do { \ 469 __trace_printk_check_format(fmt, ##args); \ 470 if (__builtin_constant_p(fmt)) { \ 471 static const char *trace_printk_fmt \ 472 __attribute__((section("__trace_printk_fmt"))) = \ 473 __builtin_constant_p(fmt) ? fmt : NULL; \ 474 \ 475 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 476 } else \ 477 __trace_printk(_THIS_IP_, fmt, ##args); \ 478} while (0) 479 480extern __printf(2, 3) 481int __trace_bprintk(unsigned long ip, const char *fmt, ...); 482 483extern __printf(2, 3) 484int __trace_printk(unsigned long ip, const char *fmt, ...); 485 486extern void trace_dump_stack(void); 487 488/* 489 * The double __builtin_constant_p is because gcc will give us an error 490 * if we try to allocate the static variable to fmt if it is not a 491 * constant. Even with the outer if statement. 492 */ 493#define ftrace_vprintk(fmt, vargs) \ 494do { \ 495 if (__builtin_constant_p(fmt)) { \ 496 static const char *trace_printk_fmt \ 497 __attribute__((section("__trace_printk_fmt"))) = \ 498 __builtin_constant_p(fmt) ? fmt : NULL; \ 499 \ 500 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 501 } else \ 502 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 503} while (0) 504 505extern int 506__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 507 508extern int 509__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 510 511extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 512#else 513static inline __printf(1, 2) 514int trace_printk(const char *fmt, ...); 515 516static inline void tracing_start(void) { } 517static inline void tracing_stop(void) { } 518static inline void ftrace_off_permanent(void) { } 519static inline void trace_dump_stack(void) { } 520static inline int 521trace_printk(const char *fmt, ...) 522{ 523 return 0; 524} 525static inline int 526ftrace_vprintk(const char *fmt, va_list ap) 527{ 528 return 0; 529} 530static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 531#endif /* CONFIG_TRACING */ 532 533/* 534 * min()/max()/clamp() macros that also do 535 * strict type-checking.. See the 536 * "unnecessary" pointer comparison. 537 */ 538#define min(x, y) ({ \ 539 typeof(x) _min1 = (x); \ 540 typeof(y) _min2 = (y); \ 541 (void) (&_min1 == &_min2); \ 542 _min1 < _min2 ? _min1 : _min2; }) 543 544#define max(x, y) ({ \ 545 typeof(x) _max1 = (x); \ 546 typeof(y) _max2 = (y); \ 547 (void) (&_max1 == &_max2); \ 548 _max1 > _max2 ? _max1 : _max2; }) 549 550#define min3(x, y, z) ({ \ 551 typeof(x) _min1 = (x); \ 552 typeof(y) _min2 = (y); \ 553 typeof(z) _min3 = (z); \ 554 (void) (&_min1 == &_min2); \ 555 (void) (&_min1 == &_min3); \ 556 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \ 557 (_min2 < _min3 ? _min2 : _min3); }) 558 559#define max3(x, y, z) ({ \ 560 typeof(x) _max1 = (x); \ 561 typeof(y) _max2 = (y); \ 562 typeof(z) _max3 = (z); \ 563 (void) (&_max1 == &_max2); \ 564 (void) (&_max1 == &_max3); \ 565 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \ 566 (_max2 > _max3 ? _max2 : _max3); }) 567 568/** 569 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 570 * @x: value1 571 * @y: value2 572 */ 573#define min_not_zero(x, y) ({ \ 574 typeof(x) __x = (x); \ 575 typeof(y) __y = (y); \ 576 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 577 578/** 579 * clamp - return a value clamped to a given range with strict typechecking 580 * @val: current value 581 * @min: minimum allowable value 582 * @max: maximum allowable value 583 * 584 * This macro does strict typechecking of min/max to make sure they are of the 585 * same type as val. See the unnecessary pointer comparisons. 586 */ 587#define clamp(val, min, max) ({ \ 588 typeof(val) __val = (val); \ 589 typeof(min) __min = (min); \ 590 typeof(max) __max = (max); \ 591 (void) (&__val == &__min); \ 592 (void) (&__val == &__max); \ 593 __val = __val < __min ? __min: __val; \ 594 __val > __max ? __max: __val; }) 595 596/* 597 * ..and if you can't take the strict 598 * types, you can specify one yourself. 599 * 600 * Or not use min/max/clamp at all, of course. 601 */ 602#define min_t(type, x, y) ({ \ 603 type __min1 = (x); \ 604 type __min2 = (y); \ 605 __min1 < __min2 ? __min1: __min2; }) 606 607#define max_t(type, x, y) ({ \ 608 type __max1 = (x); \ 609 type __max2 = (y); \ 610 __max1 > __max2 ? __max1: __max2; }) 611 612/** 613 * clamp_t - return a value clamped to a given range using a given type 614 * @type: the type of variable to use 615 * @val: current value 616 * @min: minimum allowable value 617 * @max: maximum allowable value 618 * 619 * This macro does no typechecking and uses temporary variables of type 620 * 'type' to make all the comparisons. 621 */ 622#define clamp_t(type, val, min, max) ({ \ 623 type __val = (val); \ 624 type __min = (min); \ 625 type __max = (max); \ 626 __val = __val < __min ? __min: __val; \ 627 __val > __max ? __max: __val; }) 628 629/** 630 * clamp_val - return a value clamped to a given range using val's type 631 * @val: current value 632 * @min: minimum allowable value 633 * @max: maximum allowable value 634 * 635 * This macro does no typechecking and uses temporary variables of whatever 636 * type the input argument 'val' is. This is useful when val is an unsigned 637 * type and min and max are literals that will otherwise be assigned a signed 638 * integer type. 639 */ 640#define clamp_val(val, min, max) ({ \ 641 typeof(val) __val = (val); \ 642 typeof(val) __min = (min); \ 643 typeof(val) __max = (max); \ 644 __val = __val < __min ? __min: __val; \ 645 __val > __max ? __max: __val; }) 646 647 648/* 649 * swap - swap value of @a and @b 650 */ 651#define swap(a, b) \ 652 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 653 654/** 655 * container_of - cast a member of a structure out to the containing structure 656 * @ptr: the pointer to the member. 657 * @type: the type of the container struct this is embedded in. 658 * @member: the name of the member within the struct. 659 * 660 */ 661#define container_of(ptr, type, member) ({ \ 662 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 663 (type *)( (char *)__mptr - offsetof(type,member) );}) 664 665#ifdef __CHECKER__ 666#define BUILD_BUG_ON_NOT_POWER_OF_2(n) 667#define BUILD_BUG_ON_ZERO(e) (0) 668#define BUILD_BUG_ON_NULL(e) ((void*)0) 669#define BUILD_BUG_ON(condition) 670#define BUILD_BUG() (0) 671#else /* __CHECKER__ */ 672 673/* Force a compilation error if a constant expression is not a power of 2 */ 674#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \ 675 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0)) 676 677/* Force a compilation error if condition is true, but also produce a 678 result (of value 0 and type size_t), so the expression can be used 679 e.g. in a structure initializer (or where-ever else comma expressions 680 aren't permitted). */ 681#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) 682#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); })) 683 684/** 685 * BUILD_BUG_ON - break compile if a condition is true. 686 * @condition: the condition which the compiler should know is false. 687 * 688 * If you have some code which relies on certain constants being equal, or 689 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to 690 * detect if someone changes it. 691 * 692 * The implementation uses gcc's reluctance to create a negative array, but 693 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments 694 * to inline functions). So as a fallback we use the optimizer; if it can't 695 * prove the condition is false, it will cause a link error on the undefined 696 * "__build_bug_on_failed". This error message can be harder to track down 697 * though, hence the two different methods. 698 */ 699#ifndef __OPTIMIZE__ 700#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) 701#else 702extern int __build_bug_on_failed; 703#define BUILD_BUG_ON(condition) \ 704 do { \ 705 ((void)sizeof(char[1 - 2*!!(condition)])); \ 706 if (condition) __build_bug_on_failed = 1; \ 707 } while(0) 708#endif 709 710/** 711 * BUILD_BUG - break compile if used. 712 * 713 * If you have some code that you expect the compiler to eliminate at 714 * build time, you should use BUILD_BUG to detect if it is 715 * unexpectedly used. 716 */ 717#define BUILD_BUG() \ 718 do { \ 719 extern void __build_bug_failed(void) \ 720 __linktime_error("BUILD_BUG failed"); \ 721 __build_bug_failed(); \ 722 } while (0) 723 724#endif /* __CHECKER__ */ 725 726/* Trap pasters of __FUNCTION__ at compile-time */ 727#define __FUNCTION__ (__func__) 728 729/* This helps us to avoid #ifdef CONFIG_NUMA */ 730#ifdef CONFIG_NUMA 731#define NUMA_BUILD 1 732#else 733#define NUMA_BUILD 0 734#endif 735 736/* This helps us avoid #ifdef CONFIG_COMPACTION */ 737#ifdef CONFIG_COMPACTION 738#define COMPACTION_BUILD 1 739#else 740#define COMPACTION_BUILD 0 741#endif 742 743/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 744#ifdef CONFIG_FTRACE_MCOUNT_RECORD 745# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 746#endif 747 748struct sysinfo; 749extern int do_sysinfo(struct sysinfo *info); 750 751#endif /* __KERNEL__ */ 752 753#define SI_LOAD_SHIFT 16 754struct sysinfo { 755 long uptime; /* Seconds since boot */ 756 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */ 757 unsigned long totalram; /* Total usable main memory size */ 758 unsigned long freeram; /* Available memory size */ 759 unsigned long sharedram; /* Amount of shared memory */ 760 unsigned long bufferram; /* Memory used by buffers */ 761 unsigned long totalswap; /* Total swap space size */ 762 unsigned long freeswap; /* swap space still available */ 763 unsigned short procs; /* Number of current processes */ 764 unsigned short pad; /* explicit padding for m68k */ 765 unsigned long totalhigh; /* Total high memory size */ 766 unsigned long freehigh; /* Available high memory size */ 767 unsigned int mem_unit; /* Memory unit size in bytes */ 768 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */ 769}; 770 771#endif