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/dynamic_debug.h> 19 #include <asm/byteorder.h> 20 #include <asm/bug.h> 21 22 extern const char linux_banner[]; 23 extern const char linux_proc_banner[]; 24 25 #define USHORT_MAX ((u16)(~0U)) 26 #define SHORT_MAX ((s16)(USHORT_MAX>>1)) 27 #define SHORT_MIN (-SHORT_MAX - 1) 28 #define INT_MAX ((int)(~0U>>1)) 29 #define INT_MIN (-INT_MAX - 1) 30 #define UINT_MAX (~0U) 31 #define LONG_MAX ((long)(~0UL>>1)) 32 #define LONG_MIN (-LONG_MAX - 1) 33 #define ULONG_MAX (~0UL) 34 #define LLONG_MAX ((long long)(~0ULL>>1)) 35 #define LLONG_MIN (-LLONG_MAX - 1) 36 #define ULLONG_MAX (~0ULL) 37 38 #define STACK_MAGIC 0xdeadbeef 39 40 #define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1) 41 #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask)) 42 #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) 43 #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) 44 45 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) 46 47 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f)) 48 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d)) 49 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y)) 50 #define DIV_ROUND_CLOSEST(x, divisor)( \ 51 { \ 52 typeof(divisor) __divisor = divisor; \ 53 (((x) + ((__divisor) / 2)) / (__divisor)); \ 54 } \ 55 ) 56 57 #define _RET_IP_ (unsigned long)__builtin_return_address(0) 58 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; }) 59 60 #ifdef CONFIG_LBDAF 61 # include <asm/div64.h> 62 # define sector_div(a, b) do_div(a, b) 63 #else 64 # define sector_div(n, b)( \ 65 { \ 66 int _res; \ 67 _res = (n) % (b); \ 68 (n) /= (b); \ 69 _res; \ 70 } \ 71 ) 72 #endif 73 74 /** 75 * upper_32_bits - return bits 32-63 of a number 76 * @n: the number we're accessing 77 * 78 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress 79 * the "right shift count >= width of type" warning when that quantity is 80 * 32-bits. 81 */ 82 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16)) 83 84 /** 85 * lower_32_bits - return bits 0-31 of a number 86 * @n: the number we're accessing 87 */ 88 #define lower_32_bits(n) ((u32)(n)) 89 90 #define KERN_EMERG "<0>" /* system is unusable */ 91 #define KERN_ALERT "<1>" /* action must be taken immediately */ 92 #define KERN_CRIT "<2>" /* critical conditions */ 93 #define KERN_ERR "<3>" /* error conditions */ 94 #define KERN_WARNING "<4>" /* warning conditions */ 95 #define KERN_NOTICE "<5>" /* normal but significant condition */ 96 #define KERN_INFO "<6>" /* informational */ 97 #define KERN_DEBUG "<7>" /* debug-level messages */ 98 99 /* Use the default kernel loglevel */ 100 #define KERN_DEFAULT "<d>" 101 /* 102 * Annotation for a "continued" line of log printout (only done after a 103 * line that had no enclosing \n). Only to be used by core/arch code 104 * during early bootup (a continued line is not SMP-safe otherwise). 105 */ 106 #define KERN_CONT "<c>" 107 108 extern int console_printk[]; 109 110 #define console_loglevel (console_printk[0]) 111 #define default_message_loglevel (console_printk[1]) 112 #define minimum_console_loglevel (console_printk[2]) 113 #define default_console_loglevel (console_printk[3]) 114 115 struct completion; 116 struct pt_regs; 117 struct user; 118 119 #ifdef CONFIG_PREEMPT_VOLUNTARY 120 extern int _cond_resched(void); 121 # define might_resched() _cond_resched() 122 #else 123 # define might_resched() do { } while (0) 124 #endif 125 126 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP 127 void __might_sleep(char *file, int line, int preempt_offset); 128 /** 129 * might_sleep - annotation for functions that can sleep 130 * 131 * this macro will print a stack trace if it is executed in an atomic 132 * context (spinlock, irq-handler, ...). 133 * 134 * This is a useful debugging help to be able to catch problems early and not 135 * be bitten later when the calling function happens to sleep when it is not 136 * supposed to. 137 */ 138 # define might_sleep() \ 139 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) 140 #else 141 static inline void __might_sleep(char *file, int line, int preempt_offset) { } 142 # define might_sleep() do { might_resched(); } while (0) 143 #endif 144 145 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0) 146 147 #define abs(x) ({ \ 148 long __x = (x); \ 149 (__x < 0) ? -__x : __x; \ 150 }) 151 152 #ifdef CONFIG_PROVE_LOCKING 153 void might_fault(void); 154 #else 155 static inline void might_fault(void) 156 { 157 might_sleep(); 158 } 159 #endif 160 161 extern struct atomic_notifier_head panic_notifier_list; 162 extern long (*panic_blink)(long time); 163 NORET_TYPE void panic(const char * fmt, ...) 164 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold; 165 extern void oops_enter(void); 166 extern void oops_exit(void); 167 extern int oops_may_print(void); 168 NORET_TYPE void do_exit(long error_code) 169 ATTRIB_NORET; 170 NORET_TYPE void complete_and_exit(struct completion *, long) 171 ATTRIB_NORET; 172 extern unsigned long simple_strtoul(const char *,char **,unsigned int); 173 extern long simple_strtol(const char *,char **,unsigned int); 174 extern unsigned long long simple_strtoull(const char *,char **,unsigned int); 175 extern long long simple_strtoll(const char *,char **,unsigned int); 176 extern int strict_strtoul(const char *, unsigned int, unsigned long *); 177 extern int strict_strtol(const char *, unsigned int, long *); 178 extern int strict_strtoull(const char *, unsigned int, unsigned long long *); 179 extern int strict_strtoll(const char *, unsigned int, long long *); 180 extern int sprintf(char * buf, const char * fmt, ...) 181 __attribute__ ((format (printf, 2, 3))); 182 extern int vsprintf(char *buf, const char *, va_list) 183 __attribute__ ((format (printf, 2, 0))); 184 extern int snprintf(char * buf, size_t size, const char * fmt, ...) 185 __attribute__ ((format (printf, 3, 4))); 186 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 187 __attribute__ ((format (printf, 3, 0))); 188 extern int scnprintf(char * buf, size_t size, const char * fmt, ...) 189 __attribute__ ((format (printf, 3, 4))); 190 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 191 __attribute__ ((format (printf, 3, 0))); 192 extern char *kasprintf(gfp_t gfp, const char *fmt, ...) 193 __attribute__ ((format (printf, 2, 3))); 194 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args); 195 196 extern int sscanf(const char *, const char *, ...) 197 __attribute__ ((format (scanf, 2, 3))); 198 extern int vsscanf(const char *, const char *, va_list) 199 __attribute__ ((format (scanf, 2, 0))); 200 201 extern int get_option(char **str, int *pint); 202 extern char *get_options(const char *str, int nints, int *ints); 203 extern unsigned long long memparse(const char *ptr, char **retptr); 204 205 extern int core_kernel_text(unsigned long addr); 206 extern int __kernel_text_address(unsigned long addr); 207 extern int kernel_text_address(unsigned long addr); 208 extern int func_ptr_is_kernel_text(void *ptr); 209 210 struct pid; 211 extern struct pid *session_of_pgrp(struct pid *pgrp); 212 213 /* 214 * FW_BUG 215 * Add this to a message where you are sure the firmware is buggy or behaves 216 * really stupid or out of spec. Be aware that the responsible BIOS developer 217 * should be able to fix this issue or at least get a concrete idea of the 218 * problem by reading your message without the need of looking at the kernel 219 * code. 220 * 221 * Use it for definite and high priority BIOS bugs. 222 * 223 * FW_WARN 224 * Use it for not that clear (e.g. could the kernel messed up things already?) 225 * and medium priority BIOS bugs. 226 * 227 * FW_INFO 228 * Use this one if you want to tell the user or vendor about something 229 * suspicious, but generally harmless related to the firmware. 230 * 231 * Use it for information or very low priority BIOS bugs. 232 */ 233 #define FW_BUG "[Firmware Bug]: " 234 #define FW_WARN "[Firmware Warn]: " 235 #define FW_INFO "[Firmware Info]: " 236 237 #ifdef CONFIG_PRINTK 238 asmlinkage int vprintk(const char *fmt, va_list args) 239 __attribute__ ((format (printf, 1, 0))); 240 asmlinkage int printk(const char * fmt, ...) 241 __attribute__ ((format (printf, 1, 2))) __cold; 242 243 extern int __printk_ratelimit(const char *func); 244 #define printk_ratelimit() __printk_ratelimit(__func__) 245 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, 246 unsigned int interval_msec); 247 248 extern int printk_delay_msec; 249 250 /* 251 * Print a one-time message (analogous to WARN_ONCE() et al): 252 */ 253 #define printk_once(x...) ({ \ 254 static bool __print_once = true; \ 255 \ 256 if (__print_once) { \ 257 __print_once = false; \ 258 printk(x); \ 259 } \ 260 }) 261 262 void log_buf_kexec_setup(void); 263 #else 264 static inline int vprintk(const char *s, va_list args) 265 __attribute__ ((format (printf, 1, 0))); 266 static inline int vprintk(const char *s, va_list args) { return 0; } 267 static inline int printk(const char *s, ...) 268 __attribute__ ((format (printf, 1, 2))); 269 static inline int __cold printk(const char *s, ...) { return 0; } 270 static inline int printk_ratelimit(void) { return 0; } 271 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \ 272 unsigned int interval_msec) \ 273 { return false; } 274 275 /* No effect, but we still get type checking even in the !PRINTK case: */ 276 #define printk_once(x...) printk(x) 277 278 static inline void log_buf_kexec_setup(void) 279 { 280 } 281 #endif 282 283 extern int printk_needs_cpu(int cpu); 284 extern void printk_tick(void); 285 286 extern void asmlinkage __attribute__((format(printf, 1, 2))) 287 early_printk(const char *fmt, ...); 288 289 unsigned long int_sqrt(unsigned long); 290 291 static inline void console_silent(void) 292 { 293 console_loglevel = 0; 294 } 295 296 static inline void console_verbose(void) 297 { 298 if (console_loglevel) 299 console_loglevel = 15; 300 } 301 302 extern void bust_spinlocks(int yes); 303 extern void wake_up_klogd(void); 304 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */ 305 extern int panic_timeout; 306 extern int panic_on_oops; 307 extern int panic_on_unrecovered_nmi; 308 extern int panic_on_io_nmi; 309 extern const char *print_tainted(void); 310 extern void add_taint(unsigned flag); 311 extern int test_taint(unsigned flag); 312 extern unsigned long get_taint(void); 313 extern int root_mountflags; 314 315 /* Values used for system_state */ 316 extern enum system_states { 317 SYSTEM_BOOTING, 318 SYSTEM_RUNNING, 319 SYSTEM_HALT, 320 SYSTEM_POWER_OFF, 321 SYSTEM_RESTART, 322 SYSTEM_SUSPEND_DISK, 323 } system_state; 324 325 #define TAINT_PROPRIETARY_MODULE 0 326 #define TAINT_FORCED_MODULE 1 327 #define TAINT_UNSAFE_SMP 2 328 #define TAINT_FORCED_RMMOD 3 329 #define TAINT_MACHINE_CHECK 4 330 #define TAINT_BAD_PAGE 5 331 #define TAINT_USER 6 332 #define TAINT_DIE 7 333 #define TAINT_OVERRIDDEN_ACPI_TABLE 8 334 #define TAINT_WARN 9 335 #define TAINT_CRAP 10 336 337 extern void dump_stack(void) __cold; 338 339 enum { 340 DUMP_PREFIX_NONE, 341 DUMP_PREFIX_ADDRESS, 342 DUMP_PREFIX_OFFSET 343 }; 344 extern void hex_dump_to_buffer(const void *buf, size_t len, 345 int rowsize, int groupsize, 346 char *linebuf, size_t linebuflen, bool ascii); 347 extern void print_hex_dump(const char *level, const char *prefix_str, 348 int prefix_type, int rowsize, int groupsize, 349 const void *buf, size_t len, bool ascii); 350 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 351 const void *buf, size_t len); 352 353 extern const char hex_asc[]; 354 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)] 355 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4] 356 357 static inline char *pack_hex_byte(char *buf, u8 byte) 358 { 359 *buf++ = hex_asc_hi(byte); 360 *buf++ = hex_asc_lo(byte); 361 return buf; 362 } 363 364 #ifndef pr_fmt 365 #define pr_fmt(fmt) fmt 366 #endif 367 368 #define pr_emerg(fmt, ...) \ 369 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 370 #define pr_alert(fmt, ...) \ 371 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 372 #define pr_crit(fmt, ...) \ 373 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 374 #define pr_err(fmt, ...) \ 375 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 376 #define pr_warning(fmt, ...) \ 377 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 378 #define pr_notice(fmt, ...) \ 379 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 380 #define pr_info(fmt, ...) \ 381 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 382 #define pr_cont(fmt, ...) \ 383 printk(KERN_CONT fmt, ##__VA_ARGS__) 384 385 /* pr_devel() should produce zero code unless DEBUG is defined */ 386 #ifdef DEBUG 387 #define pr_devel(fmt, ...) \ 388 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 389 #else 390 #define pr_devel(fmt, ...) \ 391 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 392 #endif 393 394 /* If you are writing a driver, please use dev_dbg instead */ 395 #if defined(DEBUG) 396 #define pr_debug(fmt, ...) \ 397 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 398 #elif defined(CONFIG_DYNAMIC_DEBUG) 399 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */ 400 #define pr_debug(fmt, ...) do { \ 401 dynamic_pr_debug(fmt, ##__VA_ARGS__); \ 402 } while (0) 403 #else 404 #define pr_debug(fmt, ...) \ 405 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 406 #endif 407 408 /* 409 * General tracing related utility functions - trace_printk(), 410 * tracing_on/tracing_off and tracing_start()/tracing_stop 411 * 412 * Use tracing_on/tracing_off when you want to quickly turn on or off 413 * tracing. It simply enables or disables the recording of the trace events. 414 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 415 * file, which gives a means for the kernel and userspace to interact. 416 * Place a tracing_off() in the kernel where you want tracing to end. 417 * From user space, examine the trace, and then echo 1 > tracing_on 418 * to continue tracing. 419 * 420 * tracing_stop/tracing_start has slightly more overhead. It is used 421 * by things like suspend to ram where disabling the recording of the 422 * trace is not enough, but tracing must actually stop because things 423 * like calling smp_processor_id() may crash the system. 424 * 425 * Most likely, you want to use tracing_on/tracing_off. 426 */ 427 #ifdef CONFIG_RING_BUFFER 428 void tracing_on(void); 429 void tracing_off(void); 430 /* trace_off_permanent stops recording with no way to bring it back */ 431 void tracing_off_permanent(void); 432 int tracing_is_on(void); 433 #else 434 static inline void tracing_on(void) { } 435 static inline void tracing_off(void) { } 436 static inline void tracing_off_permanent(void) { } 437 static inline int tracing_is_on(void) { return 0; } 438 #endif 439 #ifdef CONFIG_TRACING 440 extern void tracing_start(void); 441 extern void tracing_stop(void); 442 extern void ftrace_off_permanent(void); 443 444 extern void 445 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); 446 447 static inline void __attribute__ ((format (printf, 1, 2))) 448 ____trace_printk_check_format(const char *fmt, ...) 449 { 450 } 451 #define __trace_printk_check_format(fmt, args...) \ 452 do { \ 453 if (0) \ 454 ____trace_printk_check_format(fmt, ##args); \ 455 } while (0) 456 457 /** 458 * trace_printk - printf formatting in the ftrace buffer 459 * @fmt: the printf format for printing 460 * 461 * Note: __trace_printk is an internal function for trace_printk and 462 * the @ip is passed in via the trace_printk macro. 463 * 464 * This function allows a kernel developer to debug fast path sections 465 * that printk is not appropriate for. By scattering in various 466 * printk like tracing in the code, a developer can quickly see 467 * where problems are occurring. 468 * 469 * This is intended as a debugging tool for the developer only. 470 * Please refrain from leaving trace_printks scattered around in 471 * your code. 472 */ 473 474 #define trace_printk(fmt, args...) \ 475 do { \ 476 __trace_printk_check_format(fmt, ##args); \ 477 if (__builtin_constant_p(fmt)) { \ 478 static const char *trace_printk_fmt \ 479 __attribute__((section("__trace_printk_fmt"))) = \ 480 __builtin_constant_p(fmt) ? fmt : NULL; \ 481 \ 482 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 483 } else \ 484 __trace_printk(_THIS_IP_, fmt, ##args); \ 485 } while (0) 486 487 extern int 488 __trace_bprintk(unsigned long ip, const char *fmt, ...) 489 __attribute__ ((format (printf, 2, 3))); 490 491 extern int 492 __trace_printk(unsigned long ip, const char *fmt, ...) 493 __attribute__ ((format (printf, 2, 3))); 494 495 /* 496 * The double __builtin_constant_p is because gcc will give us an error 497 * if we try to allocate the static variable to fmt if it is not a 498 * constant. Even with the outer if statement. 499 */ 500 #define ftrace_vprintk(fmt, vargs) \ 501 do { \ 502 if (__builtin_constant_p(fmt)) { \ 503 static const char *trace_printk_fmt \ 504 __attribute__((section("__trace_printk_fmt"))) = \ 505 __builtin_constant_p(fmt) ? fmt : NULL; \ 506 \ 507 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 508 } else \ 509 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 510 } while (0) 511 512 extern int 513 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 514 515 extern int 516 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 517 518 extern void ftrace_dump(void); 519 #else 520 static inline void 521 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } 522 static inline int 523 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); 524 525 static inline void tracing_start(void) { } 526 static inline void tracing_stop(void) { } 527 static inline void ftrace_off_permanent(void) { } 528 static inline int 529 trace_printk(const char *fmt, ...) 530 { 531 return 0; 532 } 533 static inline int 534 ftrace_vprintk(const char *fmt, va_list ap) 535 { 536 return 0; 537 } 538 static inline void ftrace_dump(void) { } 539 #endif /* CONFIG_TRACING */ 540 541 /* 542 * Display an IP address in readable format. 543 */ 544 545 #define NIPQUAD(addr) \ 546 ((unsigned char *)&addr)[0], \ 547 ((unsigned char *)&addr)[1], \ 548 ((unsigned char *)&addr)[2], \ 549 ((unsigned char *)&addr)[3] 550 #define NIPQUAD_FMT "%u.%u.%u.%u" 551 552 /* 553 * min()/max()/clamp() macros that also do 554 * strict type-checking.. See the 555 * "unnecessary" pointer comparison. 556 */ 557 #define min(x, y) ({ \ 558 typeof(x) _min1 = (x); \ 559 typeof(y) _min2 = (y); \ 560 (void) (&_min1 == &_min2); \ 561 _min1 < _min2 ? _min1 : _min2; }) 562 563 #define max(x, y) ({ \ 564 typeof(x) _max1 = (x); \ 565 typeof(y) _max2 = (y); \ 566 (void) (&_max1 == &_max2); \ 567 _max1 > _max2 ? _max1 : _max2; }) 568 569 /** 570 * clamp - return a value clamped to a given range with strict typechecking 571 * @val: current value 572 * @min: minimum allowable value 573 * @max: maximum allowable value 574 * 575 * This macro does strict typechecking of min/max to make sure they are of the 576 * same type as val. See the unnecessary pointer comparisons. 577 */ 578 #define clamp(val, min, max) ({ \ 579 typeof(val) __val = (val); \ 580 typeof(min) __min = (min); \ 581 typeof(max) __max = (max); \ 582 (void) (&__val == &__min); \ 583 (void) (&__val == &__max); \ 584 __val = __val < __min ? __min: __val; \ 585 __val > __max ? __max: __val; }) 586 587 /* 588 * ..and if you can't take the strict 589 * types, you can specify one yourself. 590 * 591 * Or not use min/max/clamp at all, of course. 592 */ 593 #define min_t(type, x, y) ({ \ 594 type __min1 = (x); \ 595 type __min2 = (y); \ 596 __min1 < __min2 ? __min1: __min2; }) 597 598 #define max_t(type, x, y) ({ \ 599 type __max1 = (x); \ 600 type __max2 = (y); \ 601 __max1 > __max2 ? __max1: __max2; }) 602 603 /** 604 * clamp_t - return a value clamped to a given range using a given type 605 * @type: the type of variable to use 606 * @val: current value 607 * @min: minimum allowable value 608 * @max: maximum allowable value 609 * 610 * This macro does no typechecking and uses temporary variables of type 611 * 'type' to make all the comparisons. 612 */ 613 #define clamp_t(type, val, min, max) ({ \ 614 type __val = (val); \ 615 type __min = (min); \ 616 type __max = (max); \ 617 __val = __val < __min ? __min: __val; \ 618 __val > __max ? __max: __val; }) 619 620 /** 621 * clamp_val - return a value clamped to a given range using val's type 622 * @val: current value 623 * @min: minimum allowable value 624 * @max: maximum allowable value 625 * 626 * This macro does no typechecking and uses temporary variables of whatever 627 * type the input argument 'val' is. This is useful when val is an unsigned 628 * type and min and max are literals that will otherwise be assigned a signed 629 * integer type. 630 */ 631 #define clamp_val(val, min, max) ({ \ 632 typeof(val) __val = (val); \ 633 typeof(val) __min = (min); \ 634 typeof(val) __max = (max); \ 635 __val = __val < __min ? __min: __val; \ 636 __val > __max ? __max: __val; }) 637 638 639 /* 640 * swap - swap value of @a and @b 641 */ 642 #define swap(a, b) \ 643 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 644 645 /** 646 * container_of - cast a member of a structure out to the containing structure 647 * @ptr: the pointer to the member. 648 * @type: the type of the container struct this is embedded in. 649 * @member: the name of the member within the struct. 650 * 651 */ 652 #define container_of(ptr, type, member) ({ \ 653 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 654 (type *)( (char *)__mptr - offsetof(type,member) );}) 655 656 struct sysinfo; 657 extern int do_sysinfo(struct sysinfo *info); 658 659 #endif /* __KERNEL__ */ 660 661 #ifndef __EXPORTED_HEADERS__ 662 #ifndef __KERNEL__ 663 #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders 664 #endif /* __KERNEL__ */ 665 #endif /* __EXPORTED_HEADERS__ */ 666 667 #define SI_LOAD_SHIFT 16 668 struct sysinfo { 669 long uptime; /* Seconds since boot */ 670 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */ 671 unsigned long totalram; /* Total usable main memory size */ 672 unsigned long freeram; /* Available memory size */ 673 unsigned long sharedram; /* Amount of shared memory */ 674 unsigned long bufferram; /* Memory used by buffers */ 675 unsigned long totalswap; /* Total swap space size */ 676 unsigned long freeswap; /* swap space still available */ 677 unsigned short procs; /* Number of current processes */ 678 unsigned short pad; /* explicit padding for m68k */ 679 unsigned long totalhigh; /* Total high memory size */ 680 unsigned long freehigh; /* Available high memory size */ 681 unsigned int mem_unit; /* Memory unit size in bytes */ 682 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */ 683 }; 684 685 /* Force a compilation error if condition is true */ 686 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition)) 687 688 /* Force a compilation error if condition is constant and true */ 689 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)])) 690 691 /* Force a compilation error if condition is true, but also produce a 692 result (of value 0 and type size_t), so the expression can be used 693 e.g. in a structure initializer (or where-ever else comma expressions 694 aren't permitted). */ 695 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) 696 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); })) 697 698 /* Trap pasters of __FUNCTION__ at compile-time */ 699 #define __FUNCTION__ (__func__) 700 701 /* This helps us to avoid #ifdef CONFIG_NUMA */ 702 #ifdef CONFIG_NUMA 703 #define NUMA_BUILD 1 704 #else 705 #define NUMA_BUILD 0 706 #endif 707 708 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 709 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 710 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 711 #endif 712 713 #endif 714