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)) 134 135 struct completion; 136 struct pt_regs; 137 struct user; 138 139 #ifdef CONFIG_PREEMPT_VOLUNTARY 140 extern 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 192 void might_fault(void); 193 #else 194 static inline void might_fault(void) 195 { 196 might_sleep(); 197 } 198 #endif 199 200 extern struct atomic_notifier_head panic_notifier_list; 201 extern long (*panic_blink)(int state); 202 __printf(1, 2) 203 void panic(const char *fmt, ...) 204 __noreturn __cold; 205 extern void oops_enter(void); 206 extern void oops_exit(void); 207 void print_oops_end_marker(void); 208 extern int oops_may_print(void); 209 void do_exit(long error_code) 210 __noreturn; 211 void complete_and_exit(struct completion *, long) 212 __noreturn; 213 214 /* Internal, do not use. */ 215 int __must_check _kstrtoul(const char *s, unsigned int base, unsigned long *res); 216 int __must_check _kstrtol(const char *s, unsigned int base, long *res); 217 218 int __must_check kstrtoull(const char *s, unsigned int base, unsigned long long *res); 219 int __must_check kstrtoll(const char *s, unsigned int base, long long *res); 220 static 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 } 232 233 static 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 } 245 246 int __must_check kstrtouint(const char *s, unsigned int base, unsigned int *res); 247 int __must_check kstrtoint(const char *s, unsigned int base, int *res); 248 249 static inline int __must_check kstrtou64(const char *s, unsigned int base, u64 *res) 250 { 251 return kstrtoull(s, base, res); 252 } 253 254 static inline int __must_check kstrtos64(const char *s, unsigned int base, s64 *res) 255 { 256 return kstrtoll(s, base, res); 257 } 258 259 static inline int __must_check kstrtou32(const char *s, unsigned int base, u32 *res) 260 { 261 return kstrtouint(s, base, res); 262 } 263 264 static inline int __must_check kstrtos32(const char *s, unsigned int base, s32 *res) 265 { 266 return kstrtoint(s, base, res); 267 } 268 269 int __must_check kstrtou16(const char *s, unsigned int base, u16 *res); 270 int __must_check kstrtos16(const char *s, unsigned int base, s16 *res); 271 int __must_check kstrtou8(const char *s, unsigned int base, u8 *res); 272 int __must_check kstrtos8(const char *s, unsigned int base, s8 *res); 273 274 int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res); 275 int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res); 276 int __must_check kstrtoul_from_user(const char __user *s, size_t count, unsigned int base, unsigned long *res); 277 int __must_check kstrtol_from_user(const char __user *s, size_t count, unsigned int base, long *res); 278 int __must_check kstrtouint_from_user(const char __user *s, size_t count, unsigned int base, unsigned int *res); 279 int __must_check kstrtoint_from_user(const char __user *s, size_t count, unsigned int base, int *res); 280 int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigned int base, u16 *res); 281 int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res); 282 int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res); 283 int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res); 284 285 static 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 } 289 290 static 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 } 294 295 static 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 } 299 300 static 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 */ 306 307 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 308 extern long simple_strtol(const char *,char **,unsigned int); 309 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 310 extern 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 315 316 extern int num_to_str(char *buf, int size, unsigned long long num); 317 318 /* lib/printf utilities */ 319 320 extern __printf(2, 3) int sprintf(char *buf, const char * fmt, ...); 321 extern __printf(2, 0) int vsprintf(char *buf, const char *, va_list); 322 extern __printf(3, 4) 323 int snprintf(char *buf, size_t size, const char *fmt, ...); 324 extern __printf(3, 0) 325 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args); 326 extern __printf(3, 4) 327 int scnprintf(char *buf, size_t size, const char *fmt, ...); 328 extern __printf(3, 0) 329 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args); 330 extern __printf(2, 3) 331 char *kasprintf(gfp_t gfp, const char *fmt, ...); 332 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 333 334 extern __scanf(2, 3) 335 int sscanf(const char *, const char *, ...); 336 extern __scanf(2, 0) 337 int vsscanf(const char *, const char *, va_list); 338 339 extern int get_option(char **str, int *pint); 340 extern char *get_options(const char *str, int nints, int *ints); 341 extern unsigned long long memparse(const char *ptr, char **retptr); 342 343 extern int core_kernel_text(unsigned long addr); 344 extern int core_kernel_data(unsigned long addr); 345 extern int __kernel_text_address(unsigned long addr); 346 extern int kernel_text_address(unsigned long addr); 347 extern int func_ptr_is_kernel_text(void *ptr); 348 349 struct pid; 350 extern struct pid *session_of_pgrp(struct pid *pgrp); 351 352 unsigned long int_sqrt(unsigned long); 353 354 extern void bust_spinlocks(int yes); 355 extern void wake_up_klogd(void); 356 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 357 extern int panic_timeout; 358 extern int panic_on_oops; 359 extern int panic_on_unrecovered_nmi; 360 extern int panic_on_io_nmi; 361 extern int sysctl_panic_on_stackoverflow; 362 extern const char *print_tainted(void); 363 extern void add_taint(unsigned flag); 364 extern int test_taint(unsigned flag); 365 extern unsigned long get_taint(void); 366 extern int root_mountflags; 367 368 extern bool early_boot_irqs_disabled; 369 370 /* Values used for system_state */ 371 extern 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 12 393 394 extern 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] 397 398 static 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 } 404 405 static inline char * __deprecated pack_hex_byte(char *buf, u8 byte) 406 { 407 return hex_byte_pack(buf, byte); 408 } 409 410 extern int hex_to_bin(char ch); 411 extern 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 */ 434 void tracing_off_permanent(void); 435 #else 436 static inline void tracing_off_permanent(void) { } 437 #endif 438 439 enum ftrace_dump_mode { 440 DUMP_NONE, 441 DUMP_ALL, 442 DUMP_ORIG, 443 }; 444 445 #ifdef CONFIG_TRACING 446 void tracing_on(void); 447 void tracing_off(void); 448 int tracing_is_on(void); 449 450 extern void tracing_start(void); 451 extern void tracing_stop(void); 452 extern void ftrace_off_permanent(void); 453 454 static inline __printf(1, 2) 455 void ____trace_printk_check_format(const char *fmt, ...) 456 { 457 } 458 #define __trace_printk_check_format(fmt, args...) \ 459 do { \ 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...) \ 482 do { \ 483 static const char *trace_printk_fmt \ 484 __attribute__((section("__trace_printk_fmt"))) = \ 485 __builtin_constant_p(fmt) ? fmt : NULL; \ 486 \ 487 __trace_printk_check_format(fmt, ##args); \ 488 \ 489 if (__builtin_constant_p(fmt)) \ 490 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 491 else \ 492 __trace_printk(_THIS_IP_, fmt, ##args); \ 493 } while (0) 494 495 extern __printf(2, 3) 496 int __trace_bprintk(unsigned long ip, const char *fmt, ...); 497 498 extern __printf(2, 3) 499 int __trace_printk(unsigned long ip, const char *fmt, ...); 500 501 extern void trace_dump_stack(void); 502 503 /* 504 * The double __builtin_constant_p is because gcc will give us an error 505 * if we try to allocate the static variable to fmt if it is not a 506 * constant. Even with the outer if statement. 507 */ 508 #define ftrace_vprintk(fmt, vargs) \ 509 do { \ 510 if (__builtin_constant_p(fmt)) { \ 511 static const char *trace_printk_fmt \ 512 __attribute__((section("__trace_printk_fmt"))) = \ 513 __builtin_constant_p(fmt) ? fmt : NULL; \ 514 \ 515 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 516 } else \ 517 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 518 } while (0) 519 520 extern int 521 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 522 523 extern int 524 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 525 526 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode); 527 #else 528 static inline __printf(1, 2) 529 int trace_printk(const char *fmt, ...); 530 531 static inline void tracing_start(void) { } 532 static inline void tracing_stop(void) { } 533 static inline void ftrace_off_permanent(void) { } 534 static inline void trace_dump_stack(void) { } 535 536 static inline void tracing_on(void) { } 537 static inline void tracing_off(void) { } 538 static inline int tracing_is_on(void) { return 0; } 539 540 static inline int 541 trace_printk(const char *fmt, ...) 542 { 543 return 0; 544 } 545 static inline int 546 ftrace_vprintk(const char *fmt, va_list ap) 547 { 548 return 0; 549 } 550 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { } 551 #endif /* CONFIG_TRACING */ 552 553 /* 554 * min()/max()/clamp() macros that also do 555 * strict type-checking.. See the 556 * "unnecessary" pointer comparison. 557 */ 558 #define min(x, y) ({ \ 559 typeof(x) _min1 = (x); \ 560 typeof(y) _min2 = (y); \ 561 (void) (&_min1 == &_min2); \ 562 _min1 < _min2 ? _min1 : _min2; }) 563 564 #define max(x, y) ({ \ 565 typeof(x) _max1 = (x); \ 566 typeof(y) _max2 = (y); \ 567 (void) (&_max1 == &_max2); \ 568 _max1 > _max2 ? _max1 : _max2; }) 569 570 #define min3(x, y, z) ({ \ 571 typeof(x) _min1 = (x); \ 572 typeof(y) _min2 = (y); \ 573 typeof(z) _min3 = (z); \ 574 (void) (&_min1 == &_min2); \ 575 (void) (&_min1 == &_min3); \ 576 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \ 577 (_min2 < _min3 ? _min2 : _min3); }) 578 579 #define max3(x, y, z) ({ \ 580 typeof(x) _max1 = (x); \ 581 typeof(y) _max2 = (y); \ 582 typeof(z) _max3 = (z); \ 583 (void) (&_max1 == &_max2); \ 584 (void) (&_max1 == &_max3); \ 585 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \ 586 (_max2 > _max3 ? _max2 : _max3); }) 587 588 /** 589 * min_not_zero - return the minimum that is _not_ zero, unless both are zero 590 * @x: value1 591 * @y: value2 592 */ 593 #define min_not_zero(x, y) ({ \ 594 typeof(x) __x = (x); \ 595 typeof(y) __y = (y); \ 596 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); }) 597 598 /** 599 * clamp - return a value clamped to a given range with strict typechecking 600 * @val: current value 601 * @min: minimum allowable value 602 * @max: maximum allowable value 603 * 604 * This macro does strict typechecking of min/max to make sure they are of the 605 * same type as val. See the unnecessary pointer comparisons. 606 */ 607 #define clamp(val, min, max) ({ \ 608 typeof(val) __val = (val); \ 609 typeof(min) __min = (min); \ 610 typeof(max) __max = (max); \ 611 (void) (&__val == &__min); \ 612 (void) (&__val == &__max); \ 613 __val = __val < __min ? __min: __val; \ 614 __val > __max ? __max: __val; }) 615 616 /* 617 * ..and if you can't take the strict 618 * types, you can specify one yourself. 619 * 620 * Or not use min/max/clamp at all, of course. 621 */ 622 #define min_t(type, x, y) ({ \ 623 type __min1 = (x); \ 624 type __min2 = (y); \ 625 __min1 < __min2 ? __min1: __min2; }) 626 627 #define max_t(type, x, y) ({ \ 628 type __max1 = (x); \ 629 type __max2 = (y); \ 630 __max1 > __max2 ? __max1: __max2; }) 631 632 /** 633 * clamp_t - return a value clamped to a given range using a given type 634 * @type: the type of variable to use 635 * @val: current value 636 * @min: minimum allowable value 637 * @max: maximum allowable value 638 * 639 * This macro does no typechecking and uses temporary variables of type 640 * 'type' to make all the comparisons. 641 */ 642 #define clamp_t(type, val, min, max) ({ \ 643 type __val = (val); \ 644 type __min = (min); \ 645 type __max = (max); \ 646 __val = __val < __min ? __min: __val; \ 647 __val > __max ? __max: __val; }) 648 649 /** 650 * clamp_val - return a value clamped to a given range using val's type 651 * @val: current value 652 * @min: minimum allowable value 653 * @max: maximum allowable value 654 * 655 * This macro does no typechecking and uses temporary variables of whatever 656 * type the input argument 'val' is. This is useful when val is an unsigned 657 * type and min and max are literals that will otherwise be assigned a signed 658 * integer type. 659 */ 660 #define clamp_val(val, min, max) ({ \ 661 typeof(val) __val = (val); \ 662 typeof(val) __min = (min); \ 663 typeof(val) __max = (max); \ 664 __val = __val < __min ? __min: __val; \ 665 __val > __max ? __max: __val; }) 666 667 668 /* 669 * swap - swap value of @a and @b 670 */ 671 #define swap(a, b) \ 672 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 673 674 /** 675 * container_of - cast a member of a structure out to the containing structure 676 * @ptr: the pointer to the member. 677 * @type: the type of the container struct this is embedded in. 678 * @member: the name of the member within the struct. 679 * 680 */ 681 #define container_of(ptr, type, member) ({ \ 682 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 683 (type *)( (char *)__mptr - offsetof(type,member) );}) 684 685 /* Trap pasters of __FUNCTION__ at compile-time */ 686 #define __FUNCTION__ (__func__) 687 688 /* This helps us to avoid #ifdef CONFIG_NUMA */ 689 #ifdef CONFIG_NUMA 690 #define NUMA_BUILD 1 691 #else 692 #define NUMA_BUILD 0 693 #endif 694 695 /* This helps us avoid #ifdef CONFIG_COMPACTION */ 696 #ifdef CONFIG_COMPACTION 697 #define COMPACTION_BUILD 1 698 #else 699 #define COMPACTION_BUILD 0 700 #endif 701 702 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 703 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 704 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 705 #endif 706 707 extern int do_sysinfo(struct sysinfo *info); 708 709 #endif /* __KERNEL__ */ 710 711 #endif 712