Linux kernel mirror (for testing)
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linux
1#ifndef _LINUX_KERNEL_H
2#define _LINUX_KERNEL_H
3
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))
9
10#ifdef __KERNEL__
11
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/printk.h>
21#include <linux/dynamic_debug.h>
22#include <asm/byteorder.h>
23#include <asm/bug.h>
24
25#define USHRT_MAX ((u16)(~0U))
26#define SHRT_MAX ((s16)(USHRT_MAX>>1))
27#define SHRT_MIN ((s16)(-SHRT_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_KERNEL((x), (a))
41#define __ALIGN_MASK(x, mask) __ALIGN_KERNEL_MASK((x), (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/*
48 * This looks more complex than it should be. But we need to
49 * get the type for the ~ right in round_down (it needs to be
50 * as wide as the result!), and we want to evaluate the macro
51 * arguments just once each.
52 */
53#define __round_mask(x, y) ((__typeof__(x))((y)-1))
54#define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
55#define round_down(x, y) ((x) & ~__round_mask(x, y))
56
57#define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
58#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
59
60/* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
61#define roundup(x, y) ( \
62{ \
63 const typeof(y) __y = y; \
64 (((x) + (__y - 1)) / __y) * __y; \
65} \
66)
67#define rounddown(x, y) ( \
68{ \
69 typeof(x) __x = (x); \
70 __x - (__x % (y)); \
71} \
72)
73#define DIV_ROUND_CLOSEST(x, divisor)( \
74{ \
75 typeof(divisor) __divisor = divisor; \
76 (((x) + ((__divisor) / 2)) / (__divisor)); \
77} \
78)
79
80#define _RET_IP_ (unsigned long)__builtin_return_address(0)
81#define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
82
83#ifdef CONFIG_LBDAF
84# include <asm/div64.h>
85# define sector_div(a, b) do_div(a, b)
86#else
87# define sector_div(n, b)( \
88{ \
89 int _res; \
90 _res = (n) % (b); \
91 (n) /= (b); \
92 _res; \
93} \
94)
95#endif
96
97/**
98 * upper_32_bits - return bits 32-63 of a number
99 * @n: the number we're accessing
100 *
101 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
102 * the "right shift count >= width of type" warning when that quantity is
103 * 32-bits.
104 */
105#define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
106
107/**
108 * lower_32_bits - return bits 0-31 of a number
109 * @n: the number we're accessing
110 */
111#define lower_32_bits(n) ((u32)(n))
112
113struct completion;
114struct pt_regs;
115struct user;
116
117#ifdef CONFIG_PREEMPT_VOLUNTARY
118extern int _cond_resched(void);
119# define might_resched() _cond_resched()
120#else
121# define might_resched() do { } while (0)
122#endif
123
124#ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
125 void __might_sleep(const char *file, int line, int preempt_offset);
126/**
127 * might_sleep - annotation for functions that can sleep
128 *
129 * this macro will print a stack trace if it is executed in an atomic
130 * context (spinlock, irq-handler, ...).
131 *
132 * This is a useful debugging help to be able to catch problems early and not
133 * be bitten later when the calling function happens to sleep when it is not
134 * supposed to.
135 */
136# define might_sleep() \
137 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
138#else
139 static inline void __might_sleep(const char *file, int line,
140 int preempt_offset) { }
141# define might_sleep() do { might_resched(); } while (0)
142#endif
143
144#define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
145
146/*
147 * abs() handles unsigned and signed longs, ints, shorts and chars. For all
148 * input types abs() returns a signed long.
149 * abs() should not be used for 64-bit types (s64, u64, long long) - use abs64()
150 * for those.
151 */
152#define abs(x) ({ \
153 long ret; \
154 if (sizeof(x) == sizeof(long)) { \
155 long __x = (x); \
156 ret = (__x < 0) ? -__x : __x; \
157 } else { \
158 int __x = (x); \
159 ret = (__x < 0) ? -__x : __x; \
160 } \
161 ret; \
162 })
163
164#define abs64(x) ({ \
165 s64 __x = (x); \
166 (__x < 0) ? -__x : __x; \
167 })
168
169#ifdef CONFIG_PROVE_LOCKING
170void might_fault(void);
171#else
172static inline void might_fault(void)
173{
174 might_sleep();
175}
176#endif
177
178extern struct atomic_notifier_head panic_notifier_list;
179extern long (*panic_blink)(int state);
180NORET_TYPE void panic(const char * fmt, ...)
181 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
182extern void oops_enter(void);
183extern void oops_exit(void);
184void print_oops_end_marker(void);
185extern int oops_may_print(void);
186NORET_TYPE void do_exit(long error_code)
187 ATTRIB_NORET;
188NORET_TYPE void complete_and_exit(struct completion *, long)
189 ATTRIB_NORET;
190extern unsigned long simple_strtoul(const char *,char **,unsigned int);
191extern long simple_strtol(const char *,char **,unsigned int);
192extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
193extern long long simple_strtoll(const char *,char **,unsigned int);
194extern int __must_check strict_strtoul(const char *, unsigned int, unsigned long *);
195extern int __must_check strict_strtol(const char *, unsigned int, long *);
196extern int __must_check strict_strtoull(const char *, unsigned int, unsigned long long *);
197extern int __must_check strict_strtoll(const char *, unsigned int, long long *);
198extern int sprintf(char * buf, const char * fmt, ...)
199 __attribute__ ((format (printf, 2, 3)));
200extern int vsprintf(char *buf, const char *, va_list)
201 __attribute__ ((format (printf, 2, 0)));
202extern int snprintf(char * buf, size_t size, const char * fmt, ...)
203 __attribute__ ((format (printf, 3, 4)));
204extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
205 __attribute__ ((format (printf, 3, 0)));
206extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
207 __attribute__ ((format (printf, 3, 4)));
208extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
209 __attribute__ ((format (printf, 3, 0)));
210extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
211 __attribute__ ((format (printf, 2, 3)));
212extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
213
214extern int sscanf(const char *, const char *, ...)
215 __attribute__ ((format (scanf, 2, 3)));
216extern int vsscanf(const char *, const char *, va_list)
217 __attribute__ ((format (scanf, 2, 0)));
218
219extern int get_option(char **str, int *pint);
220extern char *get_options(const char *str, int nints, int *ints);
221extern unsigned long long memparse(const char *ptr, char **retptr);
222
223extern int core_kernel_text(unsigned long addr);
224extern int __kernel_text_address(unsigned long addr);
225extern int kernel_text_address(unsigned long addr);
226extern int func_ptr_is_kernel_text(void *ptr);
227
228struct pid;
229extern struct pid *session_of_pgrp(struct pid *pgrp);
230
231unsigned long int_sqrt(unsigned long);
232
233extern void bust_spinlocks(int yes);
234extern void wake_up_klogd(void);
235extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
236extern int panic_timeout;
237extern int panic_on_oops;
238extern int panic_on_unrecovered_nmi;
239extern int panic_on_io_nmi;
240extern const char *print_tainted(void);
241extern void add_taint(unsigned flag);
242extern int test_taint(unsigned flag);
243extern unsigned long get_taint(void);
244extern int root_mountflags;
245
246extern bool early_boot_irqs_disabled;
247
248/* Values used for system_state */
249extern enum system_states {
250 SYSTEM_BOOTING,
251 SYSTEM_RUNNING,
252 SYSTEM_HALT,
253 SYSTEM_POWER_OFF,
254 SYSTEM_RESTART,
255 SYSTEM_SUSPEND_DISK,
256} system_state;
257
258#define TAINT_PROPRIETARY_MODULE 0
259#define TAINT_FORCED_MODULE 1
260#define TAINT_UNSAFE_SMP 2
261#define TAINT_FORCED_RMMOD 3
262#define TAINT_MACHINE_CHECK 4
263#define TAINT_BAD_PAGE 5
264#define TAINT_USER 6
265#define TAINT_DIE 7
266#define TAINT_OVERRIDDEN_ACPI_TABLE 8
267#define TAINT_WARN 9
268#define TAINT_CRAP 10
269#define TAINT_FIRMWARE_WORKAROUND 11
270
271extern const char hex_asc[];
272#define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
273#define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
274
275static inline char *pack_hex_byte(char *buf, u8 byte)
276{
277 *buf++ = hex_asc_hi(byte);
278 *buf++ = hex_asc_lo(byte);
279 return buf;
280}
281
282extern int hex_to_bin(char ch);
283extern void hex2bin(u8 *dst, const char *src, size_t count);
284
285/*
286 * General tracing related utility functions - trace_printk(),
287 * tracing_on/tracing_off and tracing_start()/tracing_stop
288 *
289 * Use tracing_on/tracing_off when you want to quickly turn on or off
290 * tracing. It simply enables or disables the recording of the trace events.
291 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
292 * file, which gives a means for the kernel and userspace to interact.
293 * Place a tracing_off() in the kernel where you want tracing to end.
294 * From user space, examine the trace, and then echo 1 > tracing_on
295 * to continue tracing.
296 *
297 * tracing_stop/tracing_start has slightly more overhead. It is used
298 * by things like suspend to ram where disabling the recording of the
299 * trace is not enough, but tracing must actually stop because things
300 * like calling smp_processor_id() may crash the system.
301 *
302 * Most likely, you want to use tracing_on/tracing_off.
303 */
304#ifdef CONFIG_RING_BUFFER
305void tracing_on(void);
306void tracing_off(void);
307/* trace_off_permanent stops recording with no way to bring it back */
308void tracing_off_permanent(void);
309int tracing_is_on(void);
310#else
311static inline void tracing_on(void) { }
312static inline void tracing_off(void) { }
313static inline void tracing_off_permanent(void) { }
314static inline int tracing_is_on(void) { return 0; }
315#endif
316
317enum ftrace_dump_mode {
318 DUMP_NONE,
319 DUMP_ALL,
320 DUMP_ORIG,
321};
322
323#ifdef CONFIG_TRACING
324extern void tracing_start(void);
325extern void tracing_stop(void);
326extern void ftrace_off_permanent(void);
327
328static inline void __attribute__ ((format (printf, 1, 2)))
329____trace_printk_check_format(const char *fmt, ...)
330{
331}
332#define __trace_printk_check_format(fmt, args...) \
333do { \
334 if (0) \
335 ____trace_printk_check_format(fmt, ##args); \
336} while (0)
337
338/**
339 * trace_printk - printf formatting in the ftrace buffer
340 * @fmt: the printf format for printing
341 *
342 * Note: __trace_printk is an internal function for trace_printk and
343 * the @ip is passed in via the trace_printk macro.
344 *
345 * This function allows a kernel developer to debug fast path sections
346 * that printk is not appropriate for. By scattering in various
347 * printk like tracing in the code, a developer can quickly see
348 * where problems are occurring.
349 *
350 * This is intended as a debugging tool for the developer only.
351 * Please refrain from leaving trace_printks scattered around in
352 * your code.
353 */
354
355#define trace_printk(fmt, args...) \
356do { \
357 __trace_printk_check_format(fmt, ##args); \
358 if (__builtin_constant_p(fmt)) { \
359 static const char *trace_printk_fmt \
360 __attribute__((section("__trace_printk_fmt"))) = \
361 __builtin_constant_p(fmt) ? fmt : NULL; \
362 \
363 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
364 } else \
365 __trace_printk(_THIS_IP_, fmt, ##args); \
366} while (0)
367
368extern int
369__trace_bprintk(unsigned long ip, const char *fmt, ...)
370 __attribute__ ((format (printf, 2, 3)));
371
372extern int
373__trace_printk(unsigned long ip, const char *fmt, ...)
374 __attribute__ ((format (printf, 2, 3)));
375
376extern void trace_dump_stack(void);
377
378/*
379 * The double __builtin_constant_p is because gcc will give us an error
380 * if we try to allocate the static variable to fmt if it is not a
381 * constant. Even with the outer if statement.
382 */
383#define ftrace_vprintk(fmt, vargs) \
384do { \
385 if (__builtin_constant_p(fmt)) { \
386 static const char *trace_printk_fmt \
387 __attribute__((section("__trace_printk_fmt"))) = \
388 __builtin_constant_p(fmt) ? fmt : NULL; \
389 \
390 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
391 } else \
392 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
393} while (0)
394
395extern int
396__ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
397
398extern int
399__ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
400
401extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
402#else
403static inline int
404trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
405
406static inline void tracing_start(void) { }
407static inline void tracing_stop(void) { }
408static inline void ftrace_off_permanent(void) { }
409static inline void trace_dump_stack(void) { }
410static inline int
411trace_printk(const char *fmt, ...)
412{
413 return 0;
414}
415static inline int
416ftrace_vprintk(const char *fmt, va_list ap)
417{
418 return 0;
419}
420static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
421#endif /* CONFIG_TRACING */
422
423/*
424 * min()/max()/clamp() macros that also do
425 * strict type-checking.. See the
426 * "unnecessary" pointer comparison.
427 */
428#define min(x, y) ({ \
429 typeof(x) _min1 = (x); \
430 typeof(y) _min2 = (y); \
431 (void) (&_min1 == &_min2); \
432 _min1 < _min2 ? _min1 : _min2; })
433
434#define max(x, y) ({ \
435 typeof(x) _max1 = (x); \
436 typeof(y) _max2 = (y); \
437 (void) (&_max1 == &_max2); \
438 _max1 > _max2 ? _max1 : _max2; })
439
440#define min3(x, y, z) ({ \
441 typeof(x) _min1 = (x); \
442 typeof(y) _min2 = (y); \
443 typeof(z) _min3 = (z); \
444 (void) (&_min1 == &_min2); \
445 (void) (&_min1 == &_min3); \
446 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
447 (_min2 < _min3 ? _min2 : _min3); })
448
449#define max3(x, y, z) ({ \
450 typeof(x) _max1 = (x); \
451 typeof(y) _max2 = (y); \
452 typeof(z) _max3 = (z); \
453 (void) (&_max1 == &_max2); \
454 (void) (&_max1 == &_max3); \
455 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
456 (_max2 > _max3 ? _max2 : _max3); })
457
458/**
459 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
460 * @x: value1
461 * @y: value2
462 */
463#define min_not_zero(x, y) ({ \
464 typeof(x) __x = (x); \
465 typeof(y) __y = (y); \
466 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
467
468/**
469 * clamp - return a value clamped to a given range with strict typechecking
470 * @val: current value
471 * @min: minimum allowable value
472 * @max: maximum allowable value
473 *
474 * This macro does strict typechecking of min/max to make sure they are of the
475 * same type as val. See the unnecessary pointer comparisons.
476 */
477#define clamp(val, min, max) ({ \
478 typeof(val) __val = (val); \
479 typeof(min) __min = (min); \
480 typeof(max) __max = (max); \
481 (void) (&__val == &__min); \
482 (void) (&__val == &__max); \
483 __val = __val < __min ? __min: __val; \
484 __val > __max ? __max: __val; })
485
486/*
487 * ..and if you can't take the strict
488 * types, you can specify one yourself.
489 *
490 * Or not use min/max/clamp at all, of course.
491 */
492#define min_t(type, x, y) ({ \
493 type __min1 = (x); \
494 type __min2 = (y); \
495 __min1 < __min2 ? __min1: __min2; })
496
497#define max_t(type, x, y) ({ \
498 type __max1 = (x); \
499 type __max2 = (y); \
500 __max1 > __max2 ? __max1: __max2; })
501
502/**
503 * clamp_t - return a value clamped to a given range using a given type
504 * @type: the type of variable to use
505 * @val: current value
506 * @min: minimum allowable value
507 * @max: maximum allowable value
508 *
509 * This macro does no typechecking and uses temporary variables of type
510 * 'type' to make all the comparisons.
511 */
512#define clamp_t(type, val, min, max) ({ \
513 type __val = (val); \
514 type __min = (min); \
515 type __max = (max); \
516 __val = __val < __min ? __min: __val; \
517 __val > __max ? __max: __val; })
518
519/**
520 * clamp_val - return a value clamped to a given range using val's type
521 * @val: current value
522 * @min: minimum allowable value
523 * @max: maximum allowable value
524 *
525 * This macro does no typechecking and uses temporary variables of whatever
526 * type the input argument 'val' is. This is useful when val is an unsigned
527 * type and min and max are literals that will otherwise be assigned a signed
528 * integer type.
529 */
530#define clamp_val(val, min, max) ({ \
531 typeof(val) __val = (val); \
532 typeof(val) __min = (min); \
533 typeof(val) __max = (max); \
534 __val = __val < __min ? __min: __val; \
535 __val > __max ? __max: __val; })
536
537
538/*
539 * swap - swap value of @a and @b
540 */
541#define swap(a, b) \
542 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
543
544/**
545 * container_of - cast a member of a structure out to the containing structure
546 * @ptr: the pointer to the member.
547 * @type: the type of the container struct this is embedded in.
548 * @member: the name of the member within the struct.
549 *
550 */
551#define container_of(ptr, type, member) ({ \
552 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
553 (type *)( (char *)__mptr - offsetof(type,member) );})
554
555struct sysinfo;
556extern int do_sysinfo(struct sysinfo *info);
557
558#endif /* __KERNEL__ */
559
560#define SI_LOAD_SHIFT 16
561struct sysinfo {
562 long uptime; /* Seconds since boot */
563 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
564 unsigned long totalram; /* Total usable main memory size */
565 unsigned long freeram; /* Available memory size */
566 unsigned long sharedram; /* Amount of shared memory */
567 unsigned long bufferram; /* Memory used by buffers */
568 unsigned long totalswap; /* Total swap space size */
569 unsigned long freeswap; /* swap space still available */
570 unsigned short procs; /* Number of current processes */
571 unsigned short pad; /* explicit padding for m68k */
572 unsigned long totalhigh; /* Total high memory size */
573 unsigned long freehigh; /* Available high memory size */
574 unsigned int mem_unit; /* Memory unit size in bytes */
575 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
576};
577
578/* Force a compilation error if a constant expression is not a power of 2 */
579#define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
580 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
581
582/* Force a compilation error if condition is true, but also produce a
583 result (of value 0 and type size_t), so the expression can be used
584 e.g. in a structure initializer (or where-ever else comma expressions
585 aren't permitted). */
586#define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
587#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
588
589/**
590 * BUILD_BUG_ON - break compile if a condition is true.
591 * @condition: the condition which the compiler should know is false.
592 *
593 * If you have some code which relies on certain constants being equal, or
594 * other compile-time-evaluated condition, you should use BUILD_BUG_ON to
595 * detect if someone changes it.
596 *
597 * The implementation uses gcc's reluctance to create a negative array, but
598 * gcc (as of 4.4) only emits that error for obvious cases (eg. not arguments
599 * to inline functions). So as a fallback we use the optimizer; if it can't
600 * prove the condition is false, it will cause a link error on the undefined
601 * "__build_bug_on_failed". This error message can be harder to track down
602 * though, hence the two different methods.
603 */
604#ifndef __OPTIMIZE__
605#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
606#else
607extern int __build_bug_on_failed;
608#define BUILD_BUG_ON(condition) \
609 do { \
610 ((void)sizeof(char[1 - 2*!!(condition)])); \
611 if (condition) __build_bug_on_failed = 1; \
612 } while(0)
613#endif
614
615/* Trap pasters of __FUNCTION__ at compile-time */
616#define __FUNCTION__ (__func__)
617
618/* This helps us to avoid #ifdef CONFIG_NUMA */
619#ifdef CONFIG_NUMA
620#define NUMA_BUILD 1
621#else
622#define NUMA_BUILD 0
623#endif
624
625/* This helps us avoid #ifdef CONFIG_COMPACTION */
626#ifdef CONFIG_COMPACTION
627#define COMPACTION_BUILD 1
628#else
629#define COMPACTION_BUILD 0
630#endif
631
632/* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
633#ifdef CONFIG_FTRACE_MCOUNT_RECORD
634# define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
635#endif
636
637#endif