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; \ 255 \ 256 if (!__print_once) { \ 257 __print_once = true; \ 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, ...) \ 401 dynamic_pr_debug(fmt, ##__VA_ARGS__) 402 #else 403 #define pr_debug(fmt, ...) \ 404 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; }) 405 #endif 406 407 /* 408 * ratelimited messages with local ratelimit_state, 409 * no local ratelimit_state used in the !PRINTK case 410 */ 411 #ifdef CONFIG_PRINTK 412 #define printk_ratelimited(fmt, ...) ({ \ 413 static struct ratelimit_state _rs = { \ 414 .interval = DEFAULT_RATELIMIT_INTERVAL, \ 415 .burst = DEFAULT_RATELIMIT_BURST, \ 416 }; \ 417 \ 418 if (!__ratelimit(&_rs)) \ 419 printk(fmt, ##__VA_ARGS__); \ 420 }) 421 #else 422 /* No effect, but we still get type checking even in the !PRINTK case: */ 423 #define printk_ratelimited printk 424 #endif 425 426 #define pr_emerg_ratelimited(fmt, ...) \ 427 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 428 #define pr_alert_ratelimited(fmt, ...) \ 429 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 430 #define pr_crit_ratelimited(fmt, ...) \ 431 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 432 #define pr_err_ratelimited(fmt, ...) \ 433 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 434 #define pr_warning_ratelimited(fmt, ...) \ 435 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 436 #define pr_notice_ratelimited(fmt, ...) \ 437 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 438 #define pr_info_ratelimited(fmt, ...) \ 439 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 440 /* no pr_cont_ratelimited, don't do that... */ 441 /* If you are writing a driver, please use dev_dbg instead */ 442 #if defined(DEBUG) 443 #define pr_debug_ratelimited(fmt, ...) \ 444 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 445 #else 446 #define pr_debug_ratelimited(fmt, ...) \ 447 ({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \ 448 ##__VA_ARGS__); 0; }) 449 #endif 450 451 /* 452 * General tracing related utility functions - trace_printk(), 453 * tracing_on/tracing_off and tracing_start()/tracing_stop 454 * 455 * Use tracing_on/tracing_off when you want to quickly turn on or off 456 * tracing. It simply enables or disables the recording of the trace events. 457 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on 458 * file, which gives a means for the kernel and userspace to interact. 459 * Place a tracing_off() in the kernel where you want tracing to end. 460 * From user space, examine the trace, and then echo 1 > tracing_on 461 * to continue tracing. 462 * 463 * tracing_stop/tracing_start has slightly more overhead. It is used 464 * by things like suspend to ram where disabling the recording of the 465 * trace is not enough, but tracing must actually stop because things 466 * like calling smp_processor_id() may crash the system. 467 * 468 * Most likely, you want to use tracing_on/tracing_off. 469 */ 470 #ifdef CONFIG_RING_BUFFER 471 void tracing_on(void); 472 void tracing_off(void); 473 /* trace_off_permanent stops recording with no way to bring it back */ 474 void tracing_off_permanent(void); 475 int tracing_is_on(void); 476 #else 477 static inline void tracing_on(void) { } 478 static inline void tracing_off(void) { } 479 static inline void tracing_off_permanent(void) { } 480 static inline int tracing_is_on(void) { return 0; } 481 #endif 482 #ifdef CONFIG_TRACING 483 extern void tracing_start(void); 484 extern void tracing_stop(void); 485 extern void ftrace_off_permanent(void); 486 487 extern void 488 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3); 489 490 static inline void __attribute__ ((format (printf, 1, 2))) 491 ____trace_printk_check_format(const char *fmt, ...) 492 { 493 } 494 #define __trace_printk_check_format(fmt, args...) \ 495 do { \ 496 if (0) \ 497 ____trace_printk_check_format(fmt, ##args); \ 498 } while (0) 499 500 /** 501 * trace_printk - printf formatting in the ftrace buffer 502 * @fmt: the printf format for printing 503 * 504 * Note: __trace_printk is an internal function for trace_printk and 505 * the @ip is passed in via the trace_printk macro. 506 * 507 * This function allows a kernel developer to debug fast path sections 508 * that printk is not appropriate for. By scattering in various 509 * printk like tracing in the code, a developer can quickly see 510 * where problems are occurring. 511 * 512 * This is intended as a debugging tool for the developer only. 513 * Please refrain from leaving trace_printks scattered around in 514 * your code. 515 */ 516 517 #define trace_printk(fmt, args...) \ 518 do { \ 519 __trace_printk_check_format(fmt, ##args); \ 520 if (__builtin_constant_p(fmt)) { \ 521 static const char *trace_printk_fmt \ 522 __attribute__((section("__trace_printk_fmt"))) = \ 523 __builtin_constant_p(fmt) ? fmt : NULL; \ 524 \ 525 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \ 526 } else \ 527 __trace_printk(_THIS_IP_, fmt, ##args); \ 528 } while (0) 529 530 extern int 531 __trace_bprintk(unsigned long ip, const char *fmt, ...) 532 __attribute__ ((format (printf, 2, 3))); 533 534 extern int 535 __trace_printk(unsigned long ip, const char *fmt, ...) 536 __attribute__ ((format (printf, 2, 3))); 537 538 extern void trace_dump_stack(void); 539 540 /* 541 * The double __builtin_constant_p is because gcc will give us an error 542 * if we try to allocate the static variable to fmt if it is not a 543 * constant. Even with the outer if statement. 544 */ 545 #define ftrace_vprintk(fmt, vargs) \ 546 do { \ 547 if (__builtin_constant_p(fmt)) { \ 548 static const char *trace_printk_fmt \ 549 __attribute__((section("__trace_printk_fmt"))) = \ 550 __builtin_constant_p(fmt) ? fmt : NULL; \ 551 \ 552 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \ 553 } else \ 554 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \ 555 } while (0) 556 557 extern int 558 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap); 559 560 extern int 561 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap); 562 563 extern void ftrace_dump(void); 564 #else 565 static inline void 566 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { } 567 static inline int 568 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2))); 569 570 static inline void tracing_start(void) { } 571 static inline void tracing_stop(void) { } 572 static inline void ftrace_off_permanent(void) { } 573 static inline void trace_dump_stack(void) { } 574 static inline int 575 trace_printk(const char *fmt, ...) 576 { 577 return 0; 578 } 579 static inline int 580 ftrace_vprintk(const char *fmt, va_list ap) 581 { 582 return 0; 583 } 584 static inline void ftrace_dump(void) { } 585 #endif /* CONFIG_TRACING */ 586 587 /* 588 * Display an IP address in readable format. 589 */ 590 591 #define NIPQUAD(addr) \ 592 ((unsigned char *)&addr)[0], \ 593 ((unsigned char *)&addr)[1], \ 594 ((unsigned char *)&addr)[2], \ 595 ((unsigned char *)&addr)[3] 596 #define NIPQUAD_FMT "%u.%u.%u.%u" 597 598 /* 599 * min()/max()/clamp() macros that also do 600 * strict type-checking.. See the 601 * "unnecessary" pointer comparison. 602 */ 603 #define min(x, y) ({ \ 604 typeof(x) _min1 = (x); \ 605 typeof(y) _min2 = (y); \ 606 (void) (&_min1 == &_min2); \ 607 _min1 < _min2 ? _min1 : _min2; }) 608 609 #define max(x, y) ({ \ 610 typeof(x) _max1 = (x); \ 611 typeof(y) _max2 = (y); \ 612 (void) (&_max1 == &_max2); \ 613 _max1 > _max2 ? _max1 : _max2; }) 614 615 /** 616 * clamp - return a value clamped to a given range with strict typechecking 617 * @val: current value 618 * @min: minimum allowable value 619 * @max: maximum allowable value 620 * 621 * This macro does strict typechecking of min/max to make sure they are of the 622 * same type as val. See the unnecessary pointer comparisons. 623 */ 624 #define clamp(val, min, max) ({ \ 625 typeof(val) __val = (val); \ 626 typeof(min) __min = (min); \ 627 typeof(max) __max = (max); \ 628 (void) (&__val == &__min); \ 629 (void) (&__val == &__max); \ 630 __val = __val < __min ? __min: __val; \ 631 __val > __max ? __max: __val; }) 632 633 /* 634 * ..and if you can't take the strict 635 * types, you can specify one yourself. 636 * 637 * Or not use min/max/clamp at all, of course. 638 */ 639 #define min_t(type, x, y) ({ \ 640 type __min1 = (x); \ 641 type __min2 = (y); \ 642 __min1 < __min2 ? __min1: __min2; }) 643 644 #define max_t(type, x, y) ({ \ 645 type __max1 = (x); \ 646 type __max2 = (y); \ 647 __max1 > __max2 ? __max1: __max2; }) 648 649 /** 650 * clamp_t - return a value clamped to a given range using a given type 651 * @type: the type of variable to use 652 * @val: current value 653 * @min: minimum allowable value 654 * @max: maximum allowable value 655 * 656 * This macro does no typechecking and uses temporary variables of type 657 * 'type' to make all the comparisons. 658 */ 659 #define clamp_t(type, val, min, max) ({ \ 660 type __val = (val); \ 661 type __min = (min); \ 662 type __max = (max); \ 663 __val = __val < __min ? __min: __val; \ 664 __val > __max ? __max: __val; }) 665 666 /** 667 * clamp_val - return a value clamped to a given range using val's type 668 * @val: current value 669 * @min: minimum allowable value 670 * @max: maximum allowable value 671 * 672 * This macro does no typechecking and uses temporary variables of whatever 673 * type the input argument 'val' is. This is useful when val is an unsigned 674 * type and min and max are literals that will otherwise be assigned a signed 675 * integer type. 676 */ 677 #define clamp_val(val, min, max) ({ \ 678 typeof(val) __val = (val); \ 679 typeof(val) __min = (min); \ 680 typeof(val) __max = (max); \ 681 __val = __val < __min ? __min: __val; \ 682 __val > __max ? __max: __val; }) 683 684 685 /* 686 * swap - swap value of @a and @b 687 */ 688 #define swap(a, b) \ 689 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0) 690 691 /** 692 * container_of - cast a member of a structure out to the containing structure 693 * @ptr: the pointer to the member. 694 * @type: the type of the container struct this is embedded in. 695 * @member: the name of the member within the struct. 696 * 697 */ 698 #define container_of(ptr, type, member) ({ \ 699 const typeof( ((type *)0)->member ) *__mptr = (ptr); \ 700 (type *)( (char *)__mptr - offsetof(type,member) );}) 701 702 struct sysinfo; 703 extern int do_sysinfo(struct sysinfo *info); 704 705 #endif /* __KERNEL__ */ 706 707 #ifndef __EXPORTED_HEADERS__ 708 #ifndef __KERNEL__ 709 #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders 710 #endif /* __KERNEL__ */ 711 #endif /* __EXPORTED_HEADERS__ */ 712 713 #define SI_LOAD_SHIFT 16 714 struct sysinfo { 715 long uptime; /* Seconds since boot */ 716 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */ 717 unsigned long totalram; /* Total usable main memory size */ 718 unsigned long freeram; /* Available memory size */ 719 unsigned long sharedram; /* Amount of shared memory */ 720 unsigned long bufferram; /* Memory used by buffers */ 721 unsigned long totalswap; /* Total swap space size */ 722 unsigned long freeswap; /* swap space still available */ 723 unsigned short procs; /* Number of current processes */ 724 unsigned short pad; /* explicit padding for m68k */ 725 unsigned long totalhigh; /* Total high memory size */ 726 unsigned long freehigh; /* Available high memory size */ 727 unsigned int mem_unit; /* Memory unit size in bytes */ 728 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */ 729 }; 730 731 /* Force a compilation error if condition is true */ 732 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition)) 733 734 /* Force a compilation error if condition is constant and true */ 735 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)])) 736 737 /* Force a compilation error if a constant expression is not a power of 2 */ 738 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \ 739 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0)) 740 741 /* Force a compilation error if condition is true, but also produce a 742 result (of value 0 and type size_t), so the expression can be used 743 e.g. in a structure initializer (or where-ever else comma expressions 744 aren't permitted). */ 745 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); })) 746 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); })) 747 748 /* Trap pasters of __FUNCTION__ at compile-time */ 749 #define __FUNCTION__ (__func__) 750 751 /* This helps us to avoid #ifdef CONFIG_NUMA */ 752 #ifdef CONFIG_NUMA 753 #define NUMA_BUILD 1 754 #else 755 #define NUMA_BUILD 0 756 #endif 757 758 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */ 759 #ifdef CONFIG_FTRACE_MCOUNT_RECORD 760 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD 761 #endif 762 763 #endif 764