netfilter: xtables: make XT_ALIGN() usable in exported headers by exporting __ALIGN_K...
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / include / linux / kernel.h
blob284ea995646eafff71eebee1d76f834badcc6c19
1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
4 /*
5 * 'kernel.h' contains some often-used function prototypes etc
6 */
7 #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8 #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
10 #ifdef __KERNEL__
12 #include <stdarg.h>
13 #include <linux/linkage.h>
14 #include <linux/stddef.h>
15 #include <linux/types.h>
16 #include <linux/compiler.h>
17 #include <linux/bitops.h>
18 #include <linux/log2.h>
19 #include <linux/typecheck.h>
20 #include <linux/dynamic_debug.h>
21 #include <asm/byteorder.h>
22 #include <asm/bug.h>
24 extern const char linux_banner[];
25 extern const char linux_proc_banner[];
27 #define USHORT_MAX ((u16)(~0U))
28 #define SHORT_MAX ((s16)(USHORT_MAX>>1))
29 #define SHORT_MIN (-SHORT_MAX - 1)
30 #define INT_MAX ((int)(~0U>>1))
31 #define INT_MIN (-INT_MAX - 1)
32 #define UINT_MAX (~0U)
33 #define LONG_MAX ((long)(~0UL>>1))
34 #define LONG_MIN (-LONG_MAX - 1)
35 #define ULONG_MAX (~0UL)
36 #define LLONG_MAX ((long long)(~0ULL>>1))
37 #define LLONG_MIN (-LLONG_MAX - 1)
38 #define ULLONG_MAX (~0ULL)
40 #define STACK_MAGIC 0xdeadbeef
42 #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
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)
46 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
49 * This looks more complex than it should be. But we need to
50 * get the type for the ~ right in round_down (it needs to be
51 * as wide as the result!), and we want to evaluate the macro
52 * arguments just once each.
54 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
55 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
56 #define round_down(x, y) ((x) & ~__round_mask(x, y))
58 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
59 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
60 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
61 #define DIV_ROUND_CLOSEST(x, divisor)( \
62 { \
63 typeof(divisor) __divisor = divisor; \
64 (((x) + ((__divisor) / 2)) / (__divisor)); \
65 } \
68 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
69 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
71 #ifdef CONFIG_LBDAF
72 # include <asm/div64.h>
73 # define sector_div(a, b) do_div(a, b)
74 #else
75 # define sector_div(n, b)( \
76 { \
77 int _res; \
78 _res = (n) % (b); \
79 (n) /= (b); \
80 _res; \
81 } \
83 #endif
85 /**
86 * upper_32_bits - return bits 32-63 of a number
87 * @n: the number we're accessing
89 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
90 * the "right shift count >= width of type" warning when that quantity is
91 * 32-bits.
93 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
95 /**
96 * lower_32_bits - return bits 0-31 of a number
97 * @n: the number we're accessing
99 #define lower_32_bits(n) ((u32)(n))
101 #define KERN_EMERG "<0>" /* system is unusable */
102 #define KERN_ALERT "<1>" /* action must be taken immediately */
103 #define KERN_CRIT "<2>" /* critical conditions */
104 #define KERN_ERR "<3>" /* error conditions */
105 #define KERN_WARNING "<4>" /* warning conditions */
106 #define KERN_NOTICE "<5>" /* normal but significant condition */
107 #define KERN_INFO "<6>" /* informational */
108 #define KERN_DEBUG "<7>" /* debug-level messages */
110 /* Use the default kernel loglevel */
111 #define KERN_DEFAULT "<d>"
113 * Annotation for a "continued" line of log printout (only done after a
114 * line that had no enclosing \n). Only to be used by core/arch code
115 * during early bootup (a continued line is not SMP-safe otherwise).
117 #define KERN_CONT "<c>"
119 extern int console_printk[];
121 #define console_loglevel (console_printk[0])
122 #define default_message_loglevel (console_printk[1])
123 #define minimum_console_loglevel (console_printk[2])
124 #define default_console_loglevel (console_printk[3])
126 struct completion;
127 struct pt_regs;
128 struct user;
130 #ifdef CONFIG_PREEMPT_VOLUNTARY
131 extern int _cond_resched(void);
132 # define might_resched() _cond_resched()
133 #else
134 # define might_resched() do { } while (0)
135 #endif
137 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
138 void __might_sleep(const char *file, int line, int preempt_offset);
140 * might_sleep - annotation for functions that can sleep
142 * this macro will print a stack trace if it is executed in an atomic
143 * context (spinlock, irq-handler, ...).
145 * This is a useful debugging help to be able to catch problems early and not
146 * be bitten later when the calling function happens to sleep when it is not
147 * supposed to.
149 # define might_sleep() \
150 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
151 #else
152 static inline void __might_sleep(const char *file, int line,
153 int preempt_offset) { }
154 # define might_sleep() do { might_resched(); } while (0)
155 #endif
157 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
159 #define abs(x) ({ \
160 long __x = (x); \
161 (__x < 0) ? -__x : __x; \
164 #ifdef CONFIG_PROVE_LOCKING
165 void might_fault(void);
166 #else
167 static inline void might_fault(void)
169 might_sleep();
171 #endif
173 extern struct atomic_notifier_head panic_notifier_list;
174 extern long (*panic_blink)(long time);
175 NORET_TYPE void panic(const char * fmt, ...)
176 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
177 extern void oops_enter(void);
178 extern void oops_exit(void);
179 extern int oops_may_print(void);
180 NORET_TYPE void do_exit(long error_code)
181 ATTRIB_NORET;
182 NORET_TYPE void complete_and_exit(struct completion *, long)
183 ATTRIB_NORET;
184 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
185 extern long simple_strtol(const char *,char **,unsigned int);
186 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
187 extern long long simple_strtoll(const char *,char **,unsigned int);
188 extern int strict_strtoul(const char *, unsigned int, unsigned long *);
189 extern int strict_strtol(const char *, unsigned int, long *);
190 extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
191 extern int strict_strtoll(const char *, unsigned int, long long *);
192 extern int sprintf(char * buf, const char * fmt, ...)
193 __attribute__ ((format (printf, 2, 3)));
194 extern int vsprintf(char *buf, const char *, va_list)
195 __attribute__ ((format (printf, 2, 0)));
196 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
197 __attribute__ ((format (printf, 3, 4)));
198 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
199 __attribute__ ((format (printf, 3, 0)));
200 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
201 __attribute__ ((format (printf, 3, 4)));
202 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
203 __attribute__ ((format (printf, 3, 0)));
204 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
205 __attribute__ ((format (printf, 2, 3)));
206 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
208 extern int sscanf(const char *, const char *, ...)
209 __attribute__ ((format (scanf, 2, 3)));
210 extern int vsscanf(const char *, const char *, va_list)
211 __attribute__ ((format (scanf, 2, 0)));
213 extern int get_option(char **str, int *pint);
214 extern char *get_options(const char *str, int nints, int *ints);
215 extern unsigned long long memparse(const char *ptr, char **retptr);
217 extern int core_kernel_text(unsigned long addr);
218 extern int __kernel_text_address(unsigned long addr);
219 extern int kernel_text_address(unsigned long addr);
220 extern int func_ptr_is_kernel_text(void *ptr);
222 struct pid;
223 extern struct pid *session_of_pgrp(struct pid *pgrp);
226 * FW_BUG
227 * Add this to a message where you are sure the firmware is buggy or behaves
228 * really stupid or out of spec. Be aware that the responsible BIOS developer
229 * should be able to fix this issue or at least get a concrete idea of the
230 * problem by reading your message without the need of looking at the kernel
231 * code.
233 * Use it for definite and high priority BIOS bugs.
235 * FW_WARN
236 * Use it for not that clear (e.g. could the kernel messed up things already?)
237 * and medium priority BIOS bugs.
239 * FW_INFO
240 * Use this one if you want to tell the user or vendor about something
241 * suspicious, but generally harmless related to the firmware.
243 * Use it for information or very low priority BIOS bugs.
245 #define FW_BUG "[Firmware Bug]: "
246 #define FW_WARN "[Firmware Warn]: "
247 #define FW_INFO "[Firmware Info]: "
249 #ifdef CONFIG_PRINTK
250 asmlinkage int vprintk(const char *fmt, va_list args)
251 __attribute__ ((format (printf, 1, 0)));
252 asmlinkage int printk(const char * fmt, ...)
253 __attribute__ ((format (printf, 1, 2))) __cold;
255 extern int __printk_ratelimit(const char *func);
256 #define printk_ratelimit() __printk_ratelimit(__func__)
257 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
258 unsigned int interval_msec);
260 extern int printk_delay_msec;
263 * Print a one-time message (analogous to WARN_ONCE() et al):
265 #define printk_once(x...) ({ \
266 static bool __print_once; \
268 if (!__print_once) { \
269 __print_once = true; \
270 printk(x); \
274 void log_buf_kexec_setup(void);
275 #else
276 static inline int vprintk(const char *s, va_list args)
277 __attribute__ ((format (printf, 1, 0)));
278 static inline int vprintk(const char *s, va_list args) { return 0; }
279 static inline int printk(const char *s, ...)
280 __attribute__ ((format (printf, 1, 2)));
281 static inline int __cold printk(const char *s, ...) { return 0; }
282 static inline int printk_ratelimit(void) { return 0; }
283 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
284 unsigned int interval_msec) \
285 { return false; }
287 /* No effect, but we still get type checking even in the !PRINTK case: */
288 #define printk_once(x...) printk(x)
290 static inline void log_buf_kexec_setup(void)
293 #endif
295 extern int printk_needs_cpu(int cpu);
296 extern void printk_tick(void);
298 extern void asmlinkage __attribute__((format(printf, 1, 2)))
299 early_printk(const char *fmt, ...);
301 unsigned long int_sqrt(unsigned long);
303 static inline void console_silent(void)
305 console_loglevel = 0;
308 static inline void console_verbose(void)
310 if (console_loglevel)
311 console_loglevel = 15;
314 extern void bust_spinlocks(int yes);
315 extern void wake_up_klogd(void);
316 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
317 extern int panic_timeout;
318 extern int panic_on_oops;
319 extern int panic_on_unrecovered_nmi;
320 extern int panic_on_io_nmi;
321 extern const char *print_tainted(void);
322 extern void add_taint(unsigned flag);
323 extern int test_taint(unsigned flag);
324 extern unsigned long get_taint(void);
325 extern int root_mountflags;
327 /* Values used for system_state */
328 extern enum system_states {
329 SYSTEM_BOOTING,
330 SYSTEM_RUNNING,
331 SYSTEM_HALT,
332 SYSTEM_POWER_OFF,
333 SYSTEM_RESTART,
334 SYSTEM_SUSPEND_DISK,
335 } system_state;
337 #define TAINT_PROPRIETARY_MODULE 0
338 #define TAINT_FORCED_MODULE 1
339 #define TAINT_UNSAFE_SMP 2
340 #define TAINT_FORCED_RMMOD 3
341 #define TAINT_MACHINE_CHECK 4
342 #define TAINT_BAD_PAGE 5
343 #define TAINT_USER 6
344 #define TAINT_DIE 7
345 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
346 #define TAINT_WARN 9
347 #define TAINT_CRAP 10
349 extern void dump_stack(void) __cold;
351 enum {
352 DUMP_PREFIX_NONE,
353 DUMP_PREFIX_ADDRESS,
354 DUMP_PREFIX_OFFSET
356 extern void hex_dump_to_buffer(const void *buf, size_t len,
357 int rowsize, int groupsize,
358 char *linebuf, size_t linebuflen, bool ascii);
359 extern void print_hex_dump(const char *level, const char *prefix_str,
360 int prefix_type, int rowsize, int groupsize,
361 const void *buf, size_t len, bool ascii);
362 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
363 const void *buf, size_t len);
365 extern const char hex_asc[];
366 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
367 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
369 static inline char *pack_hex_byte(char *buf, u8 byte)
371 *buf++ = hex_asc_hi(byte);
372 *buf++ = hex_asc_lo(byte);
373 return buf;
376 #ifndef pr_fmt
377 #define pr_fmt(fmt) fmt
378 #endif
380 #define pr_emerg(fmt, ...) \
381 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
382 #define pr_alert(fmt, ...) \
383 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
384 #define pr_crit(fmt, ...) \
385 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
386 #define pr_err(fmt, ...) \
387 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
388 #define pr_warning(fmt, ...) \
389 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
390 #define pr_notice(fmt, ...) \
391 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
392 #define pr_info(fmt, ...) \
393 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
394 #define pr_cont(fmt, ...) \
395 printk(KERN_CONT fmt, ##__VA_ARGS__)
397 /* pr_devel() should produce zero code unless DEBUG is defined */
398 #ifdef DEBUG
399 #define pr_devel(fmt, ...) \
400 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
401 #else
402 #define pr_devel(fmt, ...) \
403 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
404 #endif
406 /* If you are writing a driver, please use dev_dbg instead */
407 #if defined(DEBUG)
408 #define pr_debug(fmt, ...) \
409 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
410 #elif defined(CONFIG_DYNAMIC_DEBUG)
411 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
412 #define pr_debug(fmt, ...) \
413 dynamic_pr_debug(fmt, ##__VA_ARGS__)
414 #else
415 #define pr_debug(fmt, ...) \
416 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
417 #endif
420 * ratelimited messages with local ratelimit_state,
421 * no local ratelimit_state used in the !PRINTK case
423 #ifdef CONFIG_PRINTK
424 #define printk_ratelimited(fmt, ...) ({ \
425 static struct ratelimit_state _rs = { \
426 .interval = DEFAULT_RATELIMIT_INTERVAL, \
427 .burst = DEFAULT_RATELIMIT_BURST, \
428 }; \
430 if (!__ratelimit(&_rs)) \
431 printk(fmt, ##__VA_ARGS__); \
433 #else
434 /* No effect, but we still get type checking even in the !PRINTK case: */
435 #define printk_ratelimited printk
436 #endif
438 #define pr_emerg_ratelimited(fmt, ...) \
439 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
440 #define pr_alert_ratelimited(fmt, ...) \
441 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
442 #define pr_crit_ratelimited(fmt, ...) \
443 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
444 #define pr_err_ratelimited(fmt, ...) \
445 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
446 #define pr_warning_ratelimited(fmt, ...) \
447 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
448 #define pr_notice_ratelimited(fmt, ...) \
449 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
450 #define pr_info_ratelimited(fmt, ...) \
451 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
452 /* no pr_cont_ratelimited, don't do that... */
453 /* If you are writing a driver, please use dev_dbg instead */
454 #if defined(DEBUG)
455 #define pr_debug_ratelimited(fmt, ...) \
456 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
457 #else
458 #define pr_debug_ratelimited(fmt, ...) \
459 ({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
460 ##__VA_ARGS__); 0; })
461 #endif
464 * General tracing related utility functions - trace_printk(),
465 * tracing_on/tracing_off and tracing_start()/tracing_stop
467 * Use tracing_on/tracing_off when you want to quickly turn on or off
468 * tracing. It simply enables or disables the recording of the trace events.
469 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
470 * file, which gives a means for the kernel and userspace to interact.
471 * Place a tracing_off() in the kernel where you want tracing to end.
472 * From user space, examine the trace, and then echo 1 > tracing_on
473 * to continue tracing.
475 * tracing_stop/tracing_start has slightly more overhead. It is used
476 * by things like suspend to ram where disabling the recording of the
477 * trace is not enough, but tracing must actually stop because things
478 * like calling smp_processor_id() may crash the system.
480 * Most likely, you want to use tracing_on/tracing_off.
482 #ifdef CONFIG_RING_BUFFER
483 void tracing_on(void);
484 void tracing_off(void);
485 /* trace_off_permanent stops recording with no way to bring it back */
486 void tracing_off_permanent(void);
487 int tracing_is_on(void);
488 #else
489 static inline void tracing_on(void) { }
490 static inline void tracing_off(void) { }
491 static inline void tracing_off_permanent(void) { }
492 static inline int tracing_is_on(void) { return 0; }
493 #endif
494 #ifdef CONFIG_TRACING
495 extern void tracing_start(void);
496 extern void tracing_stop(void);
497 extern void ftrace_off_permanent(void);
499 extern void
500 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
502 static inline void __attribute__ ((format (printf, 1, 2)))
503 ____trace_printk_check_format(const char *fmt, ...)
506 #define __trace_printk_check_format(fmt, args...) \
507 do { \
508 if (0) \
509 ____trace_printk_check_format(fmt, ##args); \
510 } while (0)
513 * trace_printk - printf formatting in the ftrace buffer
514 * @fmt: the printf format for printing
516 * Note: __trace_printk is an internal function for trace_printk and
517 * the @ip is passed in via the trace_printk macro.
519 * This function allows a kernel developer to debug fast path sections
520 * that printk is not appropriate for. By scattering in various
521 * printk like tracing in the code, a developer can quickly see
522 * where problems are occurring.
524 * This is intended as a debugging tool for the developer only.
525 * Please refrain from leaving trace_printks scattered around in
526 * your code.
529 #define trace_printk(fmt, args...) \
530 do { \
531 __trace_printk_check_format(fmt, ##args); \
532 if (__builtin_constant_p(fmt)) { \
533 static const char *trace_printk_fmt \
534 __attribute__((section("__trace_printk_fmt"))) = \
535 __builtin_constant_p(fmt) ? fmt : NULL; \
537 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
538 } else \
539 __trace_printk(_THIS_IP_, fmt, ##args); \
540 } while (0)
542 extern int
543 __trace_bprintk(unsigned long ip, const char *fmt, ...)
544 __attribute__ ((format (printf, 2, 3)));
546 extern int
547 __trace_printk(unsigned long ip, const char *fmt, ...)
548 __attribute__ ((format (printf, 2, 3)));
550 extern void trace_dump_stack(void);
553 * The double __builtin_constant_p is because gcc will give us an error
554 * if we try to allocate the static variable to fmt if it is not a
555 * constant. Even with the outer if statement.
557 #define ftrace_vprintk(fmt, vargs) \
558 do { \
559 if (__builtin_constant_p(fmt)) { \
560 static const char *trace_printk_fmt \
561 __attribute__((section("__trace_printk_fmt"))) = \
562 __builtin_constant_p(fmt) ? fmt : NULL; \
564 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
565 } else \
566 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
567 } while (0)
569 extern int
570 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
572 extern int
573 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
575 extern void ftrace_dump(void);
576 #else
577 static inline void
578 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
579 static inline int
580 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
582 static inline void tracing_start(void) { }
583 static inline void tracing_stop(void) { }
584 static inline void ftrace_off_permanent(void) { }
585 static inline void trace_dump_stack(void) { }
586 static inline int
587 trace_printk(const char *fmt, ...)
589 return 0;
591 static inline int
592 ftrace_vprintk(const char *fmt, va_list ap)
594 return 0;
596 static inline void ftrace_dump(void) { }
597 #endif /* CONFIG_TRACING */
600 * Display an IP address in readable format.
603 #define NIPQUAD(addr) \
604 ((unsigned char *)&addr)[0], \
605 ((unsigned char *)&addr)[1], \
606 ((unsigned char *)&addr)[2], \
607 ((unsigned char *)&addr)[3]
608 #define NIPQUAD_FMT "%u.%u.%u.%u"
611 * min()/max()/clamp() macros that also do
612 * strict type-checking.. See the
613 * "unnecessary" pointer comparison.
615 #define min(x, y) ({ \
616 typeof(x) _min1 = (x); \
617 typeof(y) _min2 = (y); \
618 (void) (&_min1 == &_min2); \
619 _min1 < _min2 ? _min1 : _min2; })
621 #define max(x, y) ({ \
622 typeof(x) _max1 = (x); \
623 typeof(y) _max2 = (y); \
624 (void) (&_max1 == &_max2); \
625 _max1 > _max2 ? _max1 : _max2; })
628 * clamp - return a value clamped to a given range with strict typechecking
629 * @val: current value
630 * @min: minimum allowable value
631 * @max: maximum allowable value
633 * This macro does strict typechecking of min/max to make sure they are of the
634 * same type as val. See the unnecessary pointer comparisons.
636 #define clamp(val, min, max) ({ \
637 typeof(val) __val = (val); \
638 typeof(min) __min = (min); \
639 typeof(max) __max = (max); \
640 (void) (&__val == &__min); \
641 (void) (&__val == &__max); \
642 __val = __val < __min ? __min: __val; \
643 __val > __max ? __max: __val; })
646 * ..and if you can't take the strict
647 * types, you can specify one yourself.
649 * Or not use min/max/clamp at all, of course.
651 #define min_t(type, x, y) ({ \
652 type __min1 = (x); \
653 type __min2 = (y); \
654 __min1 < __min2 ? __min1: __min2; })
656 #define max_t(type, x, y) ({ \
657 type __max1 = (x); \
658 type __max2 = (y); \
659 __max1 > __max2 ? __max1: __max2; })
662 * clamp_t - return a value clamped to a given range using a given type
663 * @type: the type of variable to use
664 * @val: current value
665 * @min: minimum allowable value
666 * @max: maximum allowable value
668 * This macro does no typechecking and uses temporary variables of type
669 * 'type' to make all the comparisons.
671 #define clamp_t(type, val, min, max) ({ \
672 type __val = (val); \
673 type __min = (min); \
674 type __max = (max); \
675 __val = __val < __min ? __min: __val; \
676 __val > __max ? __max: __val; })
679 * clamp_val - return a value clamped to a given range using val's type
680 * @val: current value
681 * @min: minimum allowable value
682 * @max: maximum allowable value
684 * This macro does no typechecking and uses temporary variables of whatever
685 * type the input argument 'val' is. This is useful when val is an unsigned
686 * type and min and max are literals that will otherwise be assigned a signed
687 * integer type.
689 #define clamp_val(val, min, max) ({ \
690 typeof(val) __val = (val); \
691 typeof(val) __min = (min); \
692 typeof(val) __max = (max); \
693 __val = __val < __min ? __min: __val; \
694 __val > __max ? __max: __val; })
698 * swap - swap value of @a and @b
700 #define swap(a, b) \
701 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
704 * container_of - cast a member of a structure out to the containing structure
705 * @ptr: the pointer to the member.
706 * @type: the type of the container struct this is embedded in.
707 * @member: the name of the member within the struct.
710 #define container_of(ptr, type, member) ({ \
711 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
712 (type *)( (char *)__mptr - offsetof(type,member) );})
714 struct sysinfo;
715 extern int do_sysinfo(struct sysinfo *info);
717 #endif /* __KERNEL__ */
719 #ifndef __EXPORTED_HEADERS__
720 #ifndef __KERNEL__
721 #warning Attempt to use kernel headers from user space, see http://kernelnewbies.org/KernelHeaders
722 #endif /* __KERNEL__ */
723 #endif /* __EXPORTED_HEADERS__ */
725 #define SI_LOAD_SHIFT 16
726 struct sysinfo {
727 long uptime; /* Seconds since boot */
728 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
729 unsigned long totalram; /* Total usable main memory size */
730 unsigned long freeram; /* Available memory size */
731 unsigned long sharedram; /* Amount of shared memory */
732 unsigned long bufferram; /* Memory used by buffers */
733 unsigned long totalswap; /* Total swap space size */
734 unsigned long freeswap; /* swap space still available */
735 unsigned short procs; /* Number of current processes */
736 unsigned short pad; /* explicit padding for m68k */
737 unsigned long totalhigh; /* Total high memory size */
738 unsigned long freehigh; /* Available high memory size */
739 unsigned int mem_unit; /* Memory unit size in bytes */
740 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
743 /* Force a compilation error if condition is true */
744 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
746 /* Force a compilation error if condition is constant and true */
747 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
749 /* Force a compilation error if a constant expression is not a power of 2 */
750 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
751 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
753 /* Force a compilation error if condition is true, but also produce a
754 result (of value 0 and type size_t), so the expression can be used
755 e.g. in a structure initializer (or where-ever else comma expressions
756 aren't permitted). */
757 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
758 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
760 /* Trap pasters of __FUNCTION__ at compile-time */
761 #define __FUNCTION__ (__func__)
763 /* This helps us to avoid #ifdef CONFIG_NUMA */
764 #ifdef CONFIG_NUMA
765 #define NUMA_BUILD 1
766 #else
767 #define NUMA_BUILD 0
768 #endif
770 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
771 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
772 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
773 #endif
775 #endif