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