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_LBD 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 /* 101 * Annotation for a "continued" line of log printout (only done after a 102 * line that had no enclosing \n). Only to be used by core/arch code 103 * during early bootup (a continued line is not SMP-safe otherwise). 104 */ 105 #define KERN_CONT "" 106 107 extern int console_printk[]; 108 109 #define console_loglevel (console_printk[0]) 110 #define default_message_loglevel (console_printk[1]) 111 #define minimum_console_loglevel (console_printk[2]) 112 #define default_console_loglevel (console_printk[3]) 113 114 struct completion; 115 struct pt_regs; 116 struct user; 117 118 #ifdef CONFIG_PREEMPT_VOLUNTARY 119 extern int _cond_resched(void); 120 # define might_resched() _cond_resched() 121 #else 122 # define might_resched() do { } while (0) 123 #endif 124 125 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP 126 void __might_sleep(char *file, int line); 127 /** 128 * might_sleep - annotation for functions that can sleep 129 * 130 * this macro will print a stack trace if it is executed in an atomic 131 * context (spinlock, irq-handler, ...). 132 * 133 * This is a useful debugging help to be able to catch problems early and not 134 * be bitten later when the calling function happens to sleep when it is not 135 * supposed to. 136 */ 137 # define might_sleep() \ 138 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0) 139 #else 140 # define might_sleep() do { might_resched(); } while (0) 141 #endif 142 143 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 144 145 #define abs(x) ({ \ 146 int __x = (x); \ 147 (__x < 0) ? -__x : __x; \ 148 }) 149 150 #ifdef CONFIG_PROVE_LOCKING 151 void might_fault(void); 152 #else 153 static inline void might_fault(void) 154 { 155 might_sleep(); 156 } 157 #endif 158 159 extern struct atomic_notifier_head panic_notifier_list; 160 extern long (*panic_blink)(long time); 161 NORET_TYPE void panic(const char * fmt, ...) 162 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold; 163 extern void oops_enter(void); 164 extern void oops_exit(void); 165 extern int oops_may_print(void); 166 NORET_TYPE void do_exit(long error_code) 167 ATTRIB_NORET; 168 NORET_TYPE void complete_and_exit(struct completion *, long) 169 ATTRIB_NORET; 170 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 171 extern long simple_strtol(const char *,char **,unsigned int); 172 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 173 extern long long simple_strtoll(const char *,char **,unsigned int); 174 extern int strict_strtoul(const char *, unsigned int, unsigned long *); 175 extern int strict_strtol(const char *, unsigned int, long *); 176 extern int strict_strtoull(const char *, unsigned int, unsigned long long *); 177 extern int strict_strtoll(const char *, unsigned int, long long *); 178 extern int sprintf(char * buf, const char * fmt, ...) 179 __attribute__ ((format (printf, 2, 3))); 180 extern int vsprintf(char *buf, const char *, va_list) 181 __attribute__ ((format (printf, 2, 0))); 182 extern int snprintf(char * buf, size_t size, const char * fmt, ...) 183 __attribute__ ((format (printf, 3, 4))); 184 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 185 __attribute__ ((format (printf, 3, 0))); 186 extern int scnprintf(char * buf, size_t size, const char * fmt, ...) 187 __attribute__ ((format (printf, 3, 4))); 188 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 189 __attribute__ ((format (printf, 3, 0))); 190 extern char *kasprintf(gfp_t gfp, const char *fmt, ...) 191 __attribute__ ((format (printf, 2, 3))); 192 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 193 194 extern int sscanf(const char *, const char *, ...) 195 __attribute__ ((format (scanf, 2, 3))); 196 extern int vsscanf(const char *, const char *, va_list) 197 __attribute__ ((format (scanf, 2, 0))); 198 199 extern int get_option(char **str, int *pint); 200 extern char *get_options(const char *str, int nints, int *ints); 201 extern unsigned long long memparse(const char *ptr, char **retptr); 202 203 extern int core_kernel_text(unsigned long addr); 204 extern int __kernel_text_address(unsigned long addr); 205 extern int kernel_text_address(unsigned long addr); 206 extern int func_ptr_is_kernel_text(void *ptr); 207 208 struct pid; 209 extern struct pid *session_of_pgrp(struct pid *pgrp); 210 211 /* 212 * FW_BUG 213 * Add this to a message where you are sure the firmware is buggy or behaves 214 * really stupid or out of spec. Be aware that the responsible BIOS developer 215 * should be able to fix this issue or at least get a concrete idea of the 216 * problem by reading your message without the need of looking at the kernel 217 * code. 218 * 219 * Use it for definite and high priority BIOS bugs. 220 * 221 * FW_WARN 222 * Use it for not that clear (e.g. could the kernel messed up things already?) 223 * and medium priority BIOS bugs. 224 * 225 * FW_INFO 226 * Use this one if you want to tell the user or vendor about something 227 * suspicious, but generally harmless related to the firmware. 228 * 229 * Use it for information or very low priority BIOS bugs. 230 */ 231 #define FW_BUG "[Firmware Bug]: " 232 #define FW_WARN "[Firmware Warn]: " 233 #define FW_INFO "[Firmware Info]: " 234 235 #ifdef CONFIG_PRINTK 236 asmlinkage int vprintk(const char *fmt, va_list args) 237 __attribute__ ((format (printf, 1, 0))); 238 asmlinkage int printk(const char * fmt, ...) 239 __attribute__ ((format (printf, 1, 2))) __cold; 240 241 extern struct ratelimit_state printk_ratelimit_state; 242 extern int printk_ratelimit(void); 243 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, 244 unsigned int interval_msec); 245 246 /* 247 * Print a one-time message (analogous to WARN_ONCE() et al): 248 */ 249 #define printk_once(x...) ({ \ 250 static int __print_once = 1; \ 251 \ 252 if (__print_once) { \ 253 __print_once = 0; \ 254 printk(x); \ 255 } \ 256 }) 257 258 void log_buf_kexec_setup(void); 259 #else 260 static inline int vprintk(const char *s, va_list args) 261 __attribute__ ((format (printf, 1, 0))); 262 static inline int vprintk(const char *s, va_list args) { return 0; } 263 static inline int printk(const char *s, ...) 264 __attribute__ ((format (printf, 1, 2))); 265 static inline int __cold printk(const char *s, ...) { return 0; } 266 static inline int printk_ratelimit(void) { return 0; } 267 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \ 268 unsigned int interval_msec) \ 269 { return false; } 270 271 /* No effect, but we still get type checking even in the !PRINTK case: */ 272 #define printk_once(x...) printk(x) 273 274 static inline void log_buf_kexec_setup(void) 275 { 276 } 277 #endif 278 279 extern int printk_needs_cpu(int cpu); 280 extern void printk_tick(void); 281 282 extern void asmlinkage __attribute__((format(printf, 1, 2))) 283 early_printk(const char *fmt, ...); 284 285 unsigned long int_sqrt(unsigned long); 286 287 static inline void console_silent(void) 288 { 289 console_loglevel = 0; 290 } 291 292 static inline void console_verbose(void) 293 { 294 if (console_loglevel) 295 console_loglevel = 15; 296 } 297 298 extern void bust_spinlocks(int yes); 299 extern void wake_up_klogd(void); 300 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 301 extern int panic_timeout; 302 extern int panic_on_oops; 303 extern int panic_on_unrecovered_nmi; 304 extern const char *print_tainted(void); 305 extern void add_taint(unsigned flag); 306 extern int test_taint(unsigned flag); 307 extern unsigned long get_taint(void); 308 extern int root_mountflags; 309 310 /* Values used for system_state */ 311 extern enum system_states { 312 SYSTEM_BOOTING, 313 SYSTEM_RUNNING, 314 SYSTEM_HALT, 315 SYSTEM_POWER_OFF, 316 SYSTEM_RESTART, 317 SYSTEM_SUSPEND_DISK, 318 } system_state; 319 320 #define TAINT_PROPRIETARY_MODULE 0 321 #define TAINT_FORCED_MODULE 1 322 #define TAINT_UNSAFE_SMP 2 323 #define TAINT_FORCED_RMMOD 3 324 #define TAINT_MACHINE_CHECK 4 325 #define TAINT_BAD_PAGE 5 326 #define TAINT_USER 6 327 #define TAINT_DIE 7 328 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 329 #define TAINT_WARN 9 330 #define TAINT_CRAP 10 331 332 extern void dump_stack(void) __cold; 333 334 enum { 335 DUMP_PREFIX_NONE, 336 DUMP_PREFIX_ADDRESS, 337 DUMP_PREFIX_OFFSET 338 }; 339 extern void hex_dump_to_buffer(const void *buf, size_t len, 340 int rowsize, int groupsize, 341 char *linebuf, size_t linebuflen, bool ascii); 342 extern void print_hex_dump(const char *level, const char *prefix_str, 343 int prefix_type, int rowsize, int groupsize, 344 const void *buf, size_t len, bool ascii); 345 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 346 const void *buf, size_t len); 347 348 extern const char hex_asc[]; 349 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 350 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 351 352 static inline char *pack_hex_byte(char *buf, u8 byte) 353 { 354 *buf++ = hex_asc_hi(byte); 355 *buf++ = hex_asc_lo(byte); 356 return buf; 357 } 358 359 #ifndef pr_fmt 360 #define pr_fmt(fmt) fmt 361 #endif 362 363 #define pr_emerg(fmt, ...) \ 364 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 365 #define pr_alert(fmt, ...) \ 366 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 367 #define pr_crit(fmt, ...) \ 368 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 369 #define pr_err(fmt, ...) \ 370 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 371 #define pr_warning(fmt, ...) \ 372 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 373 #define pr_notice(fmt, ...) \ 374 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 375 #define pr_info(fmt, ...) \ 376 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 377 #define pr_cont(fmt, ...) \ 378 printk(KERN_CONT fmt, ##__VA_ARGS__) 379 380 /* pr_devel() should produce zero code unless DEBUG is defined */ 381 #ifdef DEBUG 382 #define pr_devel(fmt, ...) \ 383 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 384 #else 385 #define pr_devel(fmt, ...) \ 386 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 387 #endif 388 389 /* If you are writing a driver, please use dev_dbg instead */ 390 #if defined(DEBUG) 391 #define pr_debug(fmt, ...) \ 392 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 393 #elif defined(CONFIG_DYNAMIC_DEBUG) 394 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */ 395 #define pr_debug(fmt, ...) do { \ 396 dynamic_pr_debug(fmt, ##__VA_ARGS__); \ 397 } while (0) 398 #else 399 #define pr_debug(fmt, ...) \ 400 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 401 #endif 402 403 /* 404 * General tracing related utility functions - trace_printk(), 405 * tracing_on/tracing_off and tracing_start()/tracing_stop 406 * 407 * Use tracing_on/tracing_off when you want to quickly turn on or off 408 * tracing. It simply enables or disables the recording of the trace events. 409 * This also corresponds to the user space debugfs/tracing/tracing_on 410 * file, which gives a means for the kernel and userspace to interact. 411 * Place a tracing_off() in the kernel where you want tracing to end. 412 * From user space, examine the trace, and then echo 1 > tracing_on 413 * to continue tracing. 414 * 415 * tracing_stop/tracing_start has slightly more overhead. It is used 416 * by things like suspend to ram where disabling the recording of the 417 * trace is not enough, but tracing must actually stop because things 418 * like calling smp_processor_id() may crash the system. 419 * 420 * Most likely, you want to use tracing_on/tracing_off. 421 */ 422 #ifdef CONFIG_RING_BUFFER 423 void tracing_on(void); 424 void tracing_off(void); 425 /* trace_off_permanent stops recording with no way to bring it back */ 426 void tracing_off_permanent(void); 427 int tracing_is_on(void); 428 #else 429 static inline void tracing_on(void) { } 430 static inline void tracing_off(void) { } 431 static inline void tracing_off_permanent(void) { } 432 static inline int tracing_is_on(void) { return 0; } 433 #endif 434 #ifdef CONFIG_TRACING 435 extern void tracing_start(void); 436 extern void tracing_stop(void); 437 extern void ftrace_off_permanent(void); 438 439 extern void 440 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); 441 442 static inline void __attribute__ ((format (printf, 1, 2))) 443 ____trace_printk_check_format(const char *fmt, ...) 444 { 445 } 446 #define __trace_printk_check_format(fmt, args...) \ 447 do { \ 448 if (0) \ 449 ____trace_printk_check_format(fmt, ##args); \ 450 } while (0) 451 452 /** 453 * trace_printk - printf formatting in the ftrace buffer 454 * @fmt: the printf format for printing 455 * 456 * Note: __trace_printk is an internal function for trace_printk and 457 * the @ip is passed in via the trace_printk macro. 458 * 459 * This function allows a kernel developer to debug fast path sections 460 * that printk is not appropriate for. By scattering in various 461 * printk like tracing in the code, a developer can quickly see 462 * where problems are occurring. 463 * 464 * This is intended as a debugging tool for the developer only. 465 * Please refrain from leaving trace_printks scattered around in 466 * your code. 467 */ 468 469 #define trace_printk(fmt, args...) \ 470 do { \ 471 __trace_printk_check_format(fmt, ##args); \ 472 if (__builtin_constant_p(fmt)) { \ 473 static const char *trace_printk_fmt \ 474 __attribute__((section("__trace_printk_fmt"))) = \ 475 __builtin_constant_p(fmt) ? fmt : NULL; \ 476 \ 477 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 478 } else \ 479 __trace_printk(_THIS_IP_, fmt, ##args); \ 480 } while (0) 481 482 extern int 483 __trace_bprintk(unsigned long ip, const char *fmt, ...) 484 __attribute__ ((format (printf, 2, 3))); 485 486 extern int 487 __trace_printk(unsigned long ip, const char *fmt, ...) 488 __attribute__ ((format (printf, 2, 3))); 489 490 /* 491 * The double __builtin_constant_p is because gcc will give us an error 492 * if we try to allocate the static variable to fmt if it is not a 493 * constant. Even with the outer if statement. 494 */ 495 #define ftrace_vprintk(fmt, vargs) \ 496 do { \ 497 if (__builtin_constant_p(fmt)) { \ 498 static const char *trace_printk_fmt \ 499 __attribute__((section("__trace_printk_fmt"))) = \ 500 __builtin_constant_p(fmt) ? fmt : NULL; \ 501 \ 502 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 503 } else \ 504 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 505 } while (0) 506 507 extern int 508 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 509 510 extern int 511 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 512 513 extern void ftrace_dump(void); 514 #else 515 static inline void 516 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } 517 static inline int 518 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); 519 520 static inline void tracing_start(void) { } 521 static inline void tracing_stop(void) { } 522 static inline void ftrace_off_permanent(void) { } 523 static inline int 524 trace_printk(const char *fmt, ...) 525 { 526 return 0; 527 } 528 static inline int 529 ftrace_vprintk(const char *fmt, va_list ap) 530 { 531 return 0; 532 } 533 static inline void ftrace_dump(void) { } 534 #endif /* CONFIG_TRACING */ 535 536 /* 537 * Display an IP address in readable format. 538 */ 539 540 #define NIPQUAD(addr) \ 541 ((unsigned char *)&addr)[0], \ 542 ((unsigned char *)&addr)[1], \ 543 ((unsigned char *)&addr)[2], \ 544 ((unsigned char *)&addr)[3] 545 #define NIPQUAD_FMT "%u.%u.%u.%u" 546 547 /* 548 * min()/max()/clamp() macros that also do 549 * strict type-checking.. See the 550 * "unnecessary" pointer comparison. 551 */ 552 #define min(x, y) ({ \ 553 typeof(x) _min1 = (x); \ 554 typeof(y) _min2 = (y); \ 555 (void) (&_min1 == &_min2); \ 556 _min1 < _min2 ? _min1 : _min2; }) 557 558 #define max(x, y) ({ \ 559 typeof(x) _max1 = (x); \ 560 typeof(y) _max2 = (y); \ 561 (void) (&_max1 == &_max2); \ 562 _max1 > _max2 ? _max1 : _max2; }) 563 564 /** 565 * clamp - return a value clamped to a given range with strict typechecking 566 * @val: current value 567 * @min: minimum allowable value 568 * @max: maximum allowable value 569 * 570 * This macro does strict typechecking of min/max to make sure they are of the 571 * same type as val. See the unnecessary pointer comparisons. 572 */ 573 #define clamp(val, min, max) ({ \ 574 typeof(val) __val = (val); \ 575 typeof(min) __min = (min); \ 576 typeof(max) __max = (max); \ 577 (void) (&__val == &__min); \ 578 (void) (&__val == &__max); \ 579 __val = __val < __min ? __min: __val; \ 580 __val > __max ? __max: __val; }) 581 582 /* 583 * ..and if you can't take the strict 584 * types, you can specify one yourself. 585 * 586 * Or not use min/max/clamp at all, of course. 587 */ 588 #define min_t(type, x, y) ({ \ 589 type __min1 = (x); \ 590 type __min2 = (y); \ 591 __min1 < __min2 ? __min1: __min2; }) 592 593 #define max_t(type, x, y) ({ \ 594 type __max1 = (x); \ 595 type __max2 = (y); \ 596 __max1 > __max2 ? __max1: __max2; }) 597 598 /** 599 * clamp_t - return a value clamped to a given range using a given type 600 * @type: the type of variable to use 601 * @val: current value 602 * @min: minimum allowable value 603 * @max: maximum allowable value 604 * 605 * This macro does no typechecking and uses temporary variables of type 606 * 'type' to make all the comparisons. 607 */ 608 #define clamp_t(type, val, min, max) ({ \ 609 type __val = (val); \ 610 type __min = (min); \ 611 type __max = (max); \ 612 __val = __val < __min ? __min: __val; \ 613 __val > __max ? __max: __val; }) 614 615 /** 616 * clamp_val - return a value clamped to a given range using val's type 617 * @val: current value 618 * @min: minimum allowable value 619 * @max: maximum allowable value 620 * 621 * This macro does no typechecking and uses temporary variables of whatever 622 * type the input argument 'val' is. This is useful when val is an unsigned 623 * type and min and max are literals that will otherwise be assigned a signed 624 * integer type. 625 */ 626 #define clamp_val(val, min, max) ({ \ 627 typeof(val) __val = (val); \ 628 typeof(val) __min = (min); \ 629 typeof(val) __max = (max); \ 630 __val = __val < __min ? __min: __val; \ 631 __val > __max ? __max: __val; }) 632 633 634 /* 635 * swap - swap value of @a and @b 636 */ 637 #define swap(a, b) \ 638 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 639 640 /** 641 * container_of - cast a member of a structure out to the containing structure 642 * @ptr: the pointer to the member. 643 * @type: the type of the container struct this is embedded in. 644 * @member: the name of the member within the struct. 645 * 646 */ 647 #define container_of(ptr, type, member) ({ \ 648 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 649 (type *)( (char *)__mptr - offsetof(type,member) );}) 650 651 struct sysinfo; 652 extern int do_sysinfo(struct sysinfo *info); 653 654 #endif /* __KERNEL__ */ 655 656 #define SI_LOAD_SHIFT 16 657 struct sysinfo { 658 long uptime; /* Seconds since boot */ 659 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */ 660 unsigned long totalram; /* Total usable main memory size */ 661 unsigned long freeram; /* Available memory size */ 662 unsigned long sharedram; /* Amount of shared memory */ 663 unsigned long bufferram; /* Memory used by buffers */ 664 unsigned long totalswap; /* Total swap space size */ 665 unsigned long freeswap; /* swap space still available */ 666 unsigned short procs; /* Number of current processes */ 667 unsigned short pad; /* explicit padding for m68k */ 668 unsigned long totalhigh; /* Total high memory size */ 669 unsigned long freehigh; /* Available high memory size */ 670 unsigned int mem_unit; /* Memory unit size in bytes */ 671 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */ 672 }; 673 674 /* Force a compilation error if condition is true */ 675 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)])) 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(char[1 - 2 * !!(e)]) - 1) 682 683 /* Trap pasters of __FUNCTION__ at compile-time */ 684 #define __FUNCTION__ (__func__) 685 686 /* This helps us to avoid #ifdef CONFIG_NUMA */ 687 #ifdef CONFIG_NUMA 688 #define NUMA_BUILD 1 689 #else 690 #define NUMA_BUILD 0 691 #endif 692 693 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 694 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 695 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 696 #endif 697 698 #endif 699