1 #ifndef _LINUX_KERNEL_H 2 #define _LINUX_KERNEL_H 3 4 /* 5 * 'kernel.h' contains some often-used function prototypes etc 6 */ 7 8 #ifdef __KERNEL__ 9 10 #include <stdarg.h> 11 #include <linux/linkage.h> 12 #include <linux/stddef.h> 13 #include <linux/types.h> 14 #include <linux/compiler.h> 15 #include <linux/bitops.h> 16 #include <linux/log2.h> 17 #include <linux/typecheck.h> 18 #include <linux/ratelimit.h> 19 #include <linux/dynamic_debug.h> 20 #include <asm/byteorder.h> 21 #include <asm/bug.h> 22 23 extern const char linux_banner[]; 24 extern const char linux_proc_banner[]; 25 26 #define USHORT_MAX ((u16)(~0U)) 27 #define SHORT_MAX ((s16)(USHORT_MAX>>1)) 28 #define SHORT_MIN (-SHORT_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_MASK(x,(typeof(x))(a)-1) 42 #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(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 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 49 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) 50 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y)) 51 #define DIV_ROUND_CLOSEST(x, divisor)( \ 52 { \ 53 typeof(divisor) __divisor = divisor; \ 54 (((x) + ((__divisor) / 2)) / (__divisor)); \ 55 } \ 56 ) 57 58 #define _RET_IP_ (unsigned long)__builtin_return_address(0) 59 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 60 61 #ifdef CONFIG_LBDAF 62 # include <asm/div64.h> 63 # define sector_div(a, b) do_div(a, b) 64 #else 65 # define sector_div(n, b)( \ 66 { \ 67 int _res; \ 68 _res = (n) % (b); \ 69 (n) /= (b); \ 70 _res; \ 71 } \ 72 ) 73 #endif 74 75 /** 76 * upper_32_bits - return bits 32-63 of a number 77 * @n: the number we're accessing 78 * 79 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 80 * the "right shift count >= width of type" warning when that quantity is 81 * 32-bits. 82 */ 83 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 84 85 /** 86 * lower_32_bits - return bits 0-31 of a number 87 * @n: the number we're accessing 88 */ 89 #define lower_32_bits(n) ((u32)(n)) 90 91 #define KERN_EMERG "<0>" /* system is unusable */ 92 #define KERN_ALERT "<1>" /* action must be taken immediately */ 93 #define KERN_CRIT "<2>" /* critical conditions */ 94 #define KERN_ERR "<3>" /* error conditions */ 95 #define KERN_WARNING "<4>" /* warning conditions */ 96 #define KERN_NOTICE "<5>" /* normal but significant condition */ 97 #define KERN_INFO "<6>" /* informational */ 98 #define KERN_DEBUG "<7>" /* debug-level messages */ 99 100 /* Use the default kernel loglevel */ 101 #define KERN_DEFAULT "<d>" 102 /* 103 * Annotation for a "continued" line of log printout (only done after a 104 * line that had no enclosing \n). Only to be used by core/arch code 105 * during early bootup (a continued line is not SMP-safe otherwise). 106 */ 107 #define KERN_CONT "<c>" 108 109 extern int console_printk[]; 110 111 #define console_loglevel (console_printk[0]) 112 #define default_message_loglevel (console_printk[1]) 113 #define minimum_console_loglevel (console_printk[2]) 114 #define default_console_loglevel (console_printk[3]) 115 116 struct completion; 117 struct pt_regs; 118 struct user; 119 120 #ifdef CONFIG_PREEMPT_VOLUNTARY 121 extern int _cond_resched(void); 122 # define might_resched() _cond_resched() 123 #else 124 # define might_resched() do { } while (0) 125 #endif 126 127 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP 128 void __might_sleep(char *file, int line, int preempt_offset); 129 /** 130 * might_sleep - annotation for functions that can sleep 131 * 132 * this macro will print a stack trace if it is executed in an atomic 133 * context (spinlock, irq-handler, ...). 134 * 135 * This is a useful debugging help to be able to catch problems early and not 136 * be bitten later when the calling function happens to sleep when it is not 137 * supposed to. 138 */ 139 # define might_sleep() \ 140 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 141 #else 142 static inline void __might_sleep(char *file, int line, int preempt_offset) { } 143 # define might_sleep() do { might_resched(); } while (0) 144 #endif 145 146 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 147 148 #define abs(x) ({ \ 149 long __x = (x); \ 150 (__x < 0) ? -__x : __x; \ 151 }) 152 153 #ifdef CONFIG_PROVE_LOCKING 154 void might_fault(void); 155 #else 156 static inline void might_fault(void) 157 { 158 might_sleep(); 159 } 160 #endif 161 162 extern struct atomic_notifier_head panic_notifier_list; 163 extern long (*panic_blink)(long time); 164 NORET_TYPE void panic(const char * fmt, ...) 165 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold; 166 extern void oops_enter(void); 167 extern void oops_exit(void); 168 extern int oops_may_print(void); 169 NORET_TYPE void do_exit(long error_code) 170 ATTRIB_NORET; 171 NORET_TYPE void complete_and_exit(struct completion *, long) 172 ATTRIB_NORET; 173 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 174 extern long simple_strtol(const char *,char **,unsigned int); 175 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 176 extern long long simple_strtoll(const char *,char **,unsigned int); 177 extern int strict_strtoul(const char *, unsigned int, unsigned long *); 178 extern int strict_strtol(const char *, unsigned int, long *); 179 extern int strict_strtoull(const char *, unsigned int, unsigned long long *); 180 extern int strict_strtoll(const char *, unsigned int, long long *); 181 extern int sprintf(char * buf, const char * fmt, ...) 182 __attribute__ ((format (printf, 2, 3))); 183 extern int vsprintf(char *buf, const char *, va_list) 184 __attribute__ ((format (printf, 2, 0))); 185 extern int snprintf(char * buf, size_t size, const char * fmt, ...) 186 __attribute__ ((format (printf, 3, 4))); 187 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 188 __attribute__ ((format (printf, 3, 0))); 189 extern int scnprintf(char * buf, size_t size, const char * fmt, ...) 190 __attribute__ ((format (printf, 3, 4))); 191 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 192 __attribute__ ((format (printf, 3, 0))); 193 extern char *kasprintf(gfp_t gfp, const char *fmt, ...) 194 __attribute__ ((format (printf, 2, 3))); 195 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 196 197 extern int sscanf(const char *, const char *, ...) 198 __attribute__ ((format (scanf, 2, 3))); 199 extern int vsscanf(const char *, const char *, va_list) 200 __attribute__ ((format (scanf, 2, 0))); 201 202 extern int get_option(char **str, int *pint); 203 extern char *get_options(const char *str, int nints, int *ints); 204 extern unsigned long long memparse(const char *ptr, char **retptr); 205 206 extern int core_kernel_text(unsigned long addr); 207 extern int __kernel_text_address(unsigned long addr); 208 extern int kernel_text_address(unsigned long addr); 209 extern int func_ptr_is_kernel_text(void *ptr); 210 211 struct pid; 212 extern struct pid *session_of_pgrp(struct pid *pgrp); 213 214 /* 215 * FW_BUG 216 * Add this to a message where you are sure the firmware is buggy or behaves 217 * really stupid or out of spec. Be aware that the responsible BIOS developer 218 * should be able to fix this issue or at least get a concrete idea of the 219 * problem by reading your message without the need of looking at the kernel 220 * code. 221 * 222 * Use it for definite and high priority BIOS bugs. 223 * 224 * FW_WARN 225 * Use it for not that clear (e.g. could the kernel messed up things already?) 226 * and medium priority BIOS bugs. 227 * 228 * FW_INFO 229 * Use this one if you want to tell the user or vendor about something 230 * suspicious, but generally harmless related to the firmware. 231 * 232 * Use it for information or very low priority BIOS bugs. 233 */ 234 #define FW_BUG "[Firmware Bug]: " 235 #define FW_WARN "[Firmware Warn]: " 236 #define FW_INFO "[Firmware Info]: " 237 238 #ifdef CONFIG_PRINTK 239 asmlinkage int vprintk(const char *fmt, va_list args) 240 __attribute__ ((format (printf, 1, 0))); 241 asmlinkage int printk(const char * fmt, ...) 242 __attribute__ ((format (printf, 1, 2))) __cold; 243 244 extern struct ratelimit_state printk_ratelimit_state; 245 extern int printk_ratelimit(void); 246 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, 247 unsigned int interval_msec); 248 249 extern int printk_delay_msec; 250 251 /* 252 * Print a one-time message (analogous to WARN_ONCE() et al): 253 */ 254 #define printk_once(x...) ({ \ 255 static bool __print_once = true; \ 256 \ 257 if (__print_once) { \ 258 __print_once = false; \ 259 printk(x); \ 260 } \ 261 }) 262 263 void log_buf_kexec_setup(void); 264 #else 265 static inline int vprintk(const char *s, va_list args) 266 __attribute__ ((format (printf, 1, 0))); 267 static inline int vprintk(const char *s, va_list args) { return 0; } 268 static inline int printk(const char *s, ...) 269 __attribute__ ((format (printf, 1, 2))); 270 static inline int __cold printk(const char *s, ...) { return 0; } 271 static inline int printk_ratelimit(void) { return 0; } 272 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \ 273 unsigned int interval_msec) \ 274 { return false; } 275 276 /* No effect, but we still get type checking even in the !PRINTK case: */ 277 #define printk_once(x...) printk(x) 278 279 static inline void log_buf_kexec_setup(void) 280 { 281 } 282 #endif 283 284 extern int printk_needs_cpu(int cpu); 285 extern void printk_tick(void); 286 287 extern void asmlinkage __attribute__((format(printf, 1, 2))) 288 early_printk(const char *fmt, ...); 289 290 unsigned long int_sqrt(unsigned long); 291 292 static inline void console_silent(void) 293 { 294 console_loglevel = 0; 295 } 296 297 static inline void console_verbose(void) 298 { 299 if (console_loglevel) 300 console_loglevel = 15; 301 } 302 303 extern void bust_spinlocks(int yes); 304 extern void wake_up_klogd(void); 305 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 306 extern int panic_timeout; 307 extern int panic_on_oops; 308 extern int panic_on_unrecovered_nmi; 309 extern int panic_on_io_nmi; 310 extern const char *print_tainted(void); 311 extern void add_taint(unsigned flag); 312 extern int test_taint(unsigned flag); 313 extern unsigned long get_taint(void); 314 extern int root_mountflags; 315 316 /* Values used for system_state */ 317 extern enum system_states { 318 SYSTEM_BOOTING, 319 SYSTEM_RUNNING, 320 SYSTEM_HALT, 321 SYSTEM_POWER_OFF, 322 SYSTEM_RESTART, 323 SYSTEM_SUSPEND_DISK, 324 } system_state; 325 326 #define TAINT_PROPRIETARY_MODULE 0 327 #define TAINT_FORCED_MODULE 1 328 #define TAINT_UNSAFE_SMP 2 329 #define TAINT_FORCED_RMMOD 3 330 #define TAINT_MACHINE_CHECK 4 331 #define TAINT_BAD_PAGE 5 332 #define TAINT_USER 6 333 #define TAINT_DIE 7 334 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 335 #define TAINT_WARN 9 336 #define TAINT_CRAP 10 337 338 extern void dump_stack(void) __cold; 339 340 enum { 341 DUMP_PREFIX_NONE, 342 DUMP_PREFIX_ADDRESS, 343 DUMP_PREFIX_OFFSET 344 }; 345 extern void hex_dump_to_buffer(const void *buf, size_t len, 346 int rowsize, int groupsize, 347 char *linebuf, size_t linebuflen, bool ascii); 348 extern void print_hex_dump(const char *level, const char *prefix_str, 349 int prefix_type, int rowsize, int groupsize, 350 const void *buf, size_t len, bool ascii); 351 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 352 const void *buf, size_t len); 353 354 extern const char hex_asc[]; 355 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 356 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 357 358 static inline char *pack_hex_byte(char *buf, u8 byte) 359 { 360 *buf++ = hex_asc_hi(byte); 361 *buf++ = hex_asc_lo(byte); 362 return buf; 363 } 364 365 #ifndef pr_fmt 366 #define pr_fmt(fmt) fmt 367 #endif 368 369 #define pr_emerg(fmt, ...) \ 370 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 371 #define pr_alert(fmt, ...) \ 372 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 373 #define pr_crit(fmt, ...) \ 374 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 375 #define pr_err(fmt, ...) \ 376 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 377 #define pr_warning(fmt, ...) \ 378 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 379 #define pr_notice(fmt, ...) \ 380 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 381 #define pr_info(fmt, ...) \ 382 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 383 #define pr_cont(fmt, ...) \ 384 printk(KERN_CONT fmt, ##__VA_ARGS__) 385 386 /* pr_devel() should produce zero code unless DEBUG is defined */ 387 #ifdef DEBUG 388 #define pr_devel(fmt, ...) \ 389 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 390 #else 391 #define pr_devel(fmt, ...) \ 392 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 393 #endif 394 395 /* If you are writing a driver, please use dev_dbg instead */ 396 #if defined(DEBUG) 397 #define pr_debug(fmt, ...) \ 398 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 399 #elif defined(CONFIG_DYNAMIC_DEBUG) 400 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */ 401 #define pr_debug(fmt, ...) do { \ 402 dynamic_pr_debug(fmt, ##__VA_ARGS__); \ 403 } while (0) 404 #else 405 #define pr_debug(fmt, ...) \ 406 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 407 #endif 408 409 /* 410 * General tracing related utility functions - trace_printk(), 411 * tracing_on/tracing_off and tracing_start()/tracing_stop 412 * 413 * Use tracing_on/tracing_off when you want to quickly turn on or off 414 * tracing. It simply enables or disables the recording of the trace events. 415 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 416 * file, which gives a means for the kernel and userspace to interact. 417 * Place a tracing_off() in the kernel where you want tracing to end. 418 * From user space, examine the trace, and then echo 1 > tracing_on 419 * to continue tracing. 420 * 421 * tracing_stop/tracing_start has slightly more overhead. It is used 422 * by things like suspend to ram where disabling the recording of the 423 * trace is not enough, but tracing must actually stop because things 424 * like calling smp_processor_id() may crash the system. 425 * 426 * Most likely, you want to use tracing_on/tracing_off. 427 */ 428 #ifdef CONFIG_RING_BUFFER 429 void tracing_on(void); 430 void tracing_off(void); 431 /* trace_off_permanent stops recording with no way to bring it back */ 432 void tracing_off_permanent(void); 433 int tracing_is_on(void); 434 #else 435 static inline void tracing_on(void) { } 436 static inline void tracing_off(void) { } 437 static inline void tracing_off_permanent(void) { } 438 static inline int tracing_is_on(void) { return 0; } 439 #endif 440 #ifdef CONFIG_TRACING 441 extern void tracing_start(void); 442 extern void tracing_stop(void); 443 extern void ftrace_off_permanent(void); 444 445 extern void 446 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); 447 448 static inline void __attribute__ ((format (printf, 1, 2))) 449 ____trace_printk_check_format(const char *fmt, ...) 450 { 451 } 452 #define __trace_printk_check_format(fmt, args...) \ 453 do { \ 454 if (0) \ 455 ____trace_printk_check_format(fmt, ##args); \ 456 } while (0) 457 458 /** 459 * trace_printk - printf formatting in the ftrace buffer 460 * @fmt: the printf format for printing 461 * 462 * Note: __trace_printk is an internal function for trace_printk and 463 * the @ip is passed in via the trace_printk macro. 464 * 465 * This function allows a kernel developer to debug fast path sections 466 * that printk is not appropriate for. By scattering in various 467 * printk like tracing in the code, a developer can quickly see 468 * where problems are occurring. 469 * 470 * This is intended as a debugging tool for the developer only. 471 * Please refrain from leaving trace_printks scattered around in 472 * your code. 473 */ 474 475 #define trace_printk(fmt, args...) \ 476 do { \ 477 __trace_printk_check_format(fmt, ##args); \ 478 if (__builtin_constant_p(fmt)) { \ 479 static const char *trace_printk_fmt \ 480 __attribute__((section("__trace_printk_fmt"))) = \ 481 __builtin_constant_p(fmt) ? fmt : NULL; \ 482 \ 483 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 484 } else \ 485 __trace_printk(_THIS_IP_, fmt, ##args); \ 486 } while (0) 487 488 extern int 489 __trace_bprintk(unsigned long ip, const char *fmt, ...) 490 __attribute__ ((format (printf, 2, 3))); 491 492 extern int 493 __trace_printk(unsigned long ip, const char *fmt, ...) 494 __attribute__ ((format (printf, 2, 3))); 495 496 /* 497 * The double __builtin_constant_p is because gcc will give us an error 498 * if we try to allocate the static variable to fmt if it is not a 499 * constant. Even with the outer if statement. 500 */ 501 #define ftrace_vprintk(fmt, vargs) \ 502 do { \ 503 if (__builtin_constant_p(fmt)) { \ 504 static const char *trace_printk_fmt \ 505 __attribute__((section("__trace_printk_fmt"))) = \ 506 __builtin_constant_p(fmt) ? fmt : NULL; \ 507 \ 508 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 509 } else \ 510 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 511 } while (0) 512 513 extern int 514 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 515 516 extern int 517 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 518 519 extern void ftrace_dump(void); 520 #else 521 static inline void 522 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } 523 static inline int 524 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); 525 526 static inline void tracing_start(void) { } 527 static inline void tracing_stop(void) { } 528 static inline void ftrace_off_permanent(void) { } 529 static inline int 530 trace_printk(const char *fmt, ...) 531 { 532 return 0; 533 } 534 static inline int 535 ftrace_vprintk(const char *fmt, va_list ap) 536 { 537 return 0; 538 } 539 static inline void ftrace_dump(void) { } 540 #endif /* CONFIG_TRACING */ 541 542 /* 543 * Display an IP address in readable format. 544 */ 545 546 #define NIPQUAD(addr) \ 547 ((unsigned char *)&addr)[0], \ 548 ((unsigned char *)&addr)[1], \ 549 ((unsigned char *)&addr)[2], \ 550 ((unsigned char *)&addr)[3] 551 #define NIPQUAD_FMT "%u.%u.%u.%u" 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 /** 571 * clamp - return a value clamped to a given range with strict typechecking 572 * @val: current value 573 * @min: minimum allowable value 574 * @max: maximum allowable value 575 * 576 * This macro does strict typechecking of min/max to make sure they are of the 577 * same type as val. See the unnecessary pointer comparisons. 578 */ 579 #define clamp(val, min, max) ({ \ 580 typeof(val) __val = (val); \ 581 typeof(min) __min = (min); \ 582 typeof(max) __max = (max); \ 583 (void) (&__val == &__min); \ 584 (void) (&__val == &__max); \ 585 __val = __val < __min ? __min: __val; \ 586 __val > __max ? __max: __val; }) 587 588 /* 589 * ..and if you can't take the strict 590 * types, you can specify one yourself. 591 * 592 * Or not use min/max/clamp at all, of course. 593 */ 594 #define min_t(type, x, y) ({ \ 595 type __min1 = (x); \ 596 type __min2 = (y); \ 597 __min1 < __min2 ? __min1: __min2; }) 598 599 #define max_t(type, x, y) ({ \ 600 type __max1 = (x); \ 601 type __max2 = (y); \ 602 __max1 > __max2 ? __max1: __max2; }) 603 604 /** 605 * clamp_t - return a value clamped to a given range using a given type 606 * @type: the type of variable to use 607 * @val: current value 608 * @min: minimum allowable value 609 * @max: maximum allowable value 610 * 611 * This macro does no typechecking and uses temporary variables of type 612 * 'type' to make all the comparisons. 613 */ 614 #define clamp_t(type, val, min, max) ({ \ 615 type __val = (val); \ 616 type __min = (min); \ 617 type __max = (max); \ 618 __val = __val < __min ? __min: __val; \ 619 __val > __max ? __max: __val; }) 620 621 /** 622 * clamp_val - return a value clamped to a given range using val's type 623 * @val: current value 624 * @min: minimum allowable value 625 * @max: maximum allowable value 626 * 627 * This macro does no typechecking and uses temporary variables of whatever 628 * type the input argument 'val' is. This is useful when val is an unsigned 629 * type and min and max are literals that will otherwise be assigned a signed 630 * integer type. 631 */ 632 #define clamp_val(val, min, max) ({ \ 633 typeof(val) __val = (val); \ 634 typeof(val) __min = (min); \ 635 typeof(val) __max = (max); \ 636 __val = __val < __min ? __min: __val; \ 637 __val > __max ? __max: __val; }) 638 639 640 /* 641 * swap - swap value of @a and @b 642 */ 643 #define swap(a, b) \ 644 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 645 646 /** 647 * container_of - cast a member of a structure out to the containing structure 648 * @ptr: the pointer to the member. 649 * @type: the type of the container struct this is embedded in. 650 * @member: the name of the member within the struct. 651 * 652 */ 653 #define container_of(ptr, type, member) ({ \ 654 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 655 (type *)( (char *)__mptr - offsetof(type,member) );}) 656 657 struct sysinfo; 658 extern int do_sysinfo(struct sysinfo *info); 659 660 #endif /* __KERNEL__ */ 661 662 #ifndef __EXPORTED_HEADERS__ 663 #ifndef __KERNEL__ 664 #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders 665 #endif /* __KERNEL__ */ 666 #endif /* __EXPORTED_HEADERS__ */ 667 668 #define SI_LOAD_SHIFT 16 669 struct sysinfo { 670 long uptime; /* Seconds since boot */ 671 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */ 672 unsigned long totalram; /* Total usable main memory size */ 673 unsigned long freeram; /* Available memory size */ 674 unsigned long sharedram; /* Amount of shared memory */ 675 unsigned long bufferram; /* Memory used by buffers */ 676 unsigned long totalswap; /* Total swap space size */ 677 unsigned long freeswap; /* swap space still available */ 678 unsigned short procs; /* Number of current processes */ 679 unsigned short pad; /* explicit padding for m68k */ 680 unsigned long totalhigh; /* Total high memory size */ 681 unsigned long freehigh; /* Available high memory size */ 682 unsigned int mem_unit; /* Memory unit size in bytes */ 683 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */ 684 }; 685 686 /* Force a compilation error if condition is true */ 687 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition)) 688 689 /* Force a compilation error if condition is constant and true */ 690 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)])) 691 692 /* Force a compilation error if condition is true, but also produce a 693 result (of value 0 and type size_t), so the expression can be used 694 e.g. in a structure initializer (or where-ever else comma expressions 695 aren't permitted). */ 696 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) 697 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); })) 698 699 /* Trap pasters of __FUNCTION__ at compile-time */ 700 #define __FUNCTION__ (__func__) 701 702 /* This helps us to avoid #ifdef CONFIG_NUMA */ 703 #ifdef CONFIG_NUMA 704 #define NUMA_BUILD 1 705 #else 706 #define NUMA_BUILD 0 707 #endif 708 709 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 710 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 711 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 712 #endif 713 714 #endif 715