1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
5 * 'kernel.h' contains some often-used function prototypes etc
7 #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
8 #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
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>
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)
38 #define STACK_MAGIC 0xdeadbeef
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)
45 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
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.
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))
57 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
58 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
60 /* The `const' in roundup() prevents gcc-3.3 from calling __divdi3 */
61 #define roundup(x, y) ( \
63 const typeof(y) __y = y; \
64 (((x) + (__y - 1)) / __y) * __y; \
67 #define rounddown(x, y) ( \
69 typeof(x) __x = (x); \
73 #define DIV_ROUND_CLOSEST(x, divisor)( \
75 typeof(divisor) __divisor = divisor; \
76 (((x) + ((__divisor) / 2)) / (__divisor)); \
80 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
81 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
84 # include <asm/div64.h>
85 # define sector_div(a, b) do_div(a, b)
87 # define sector_div(n, b)( \
98 * upper_32_bits - return bits 32-63 of a number
99 * @n: the number we're accessing
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
105 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
108 * lower_32_bits - return bits 0-31 of a number
109 * @n: the number we're accessing
111 #define lower_32_bits(n) ((u32)(n))
117 #ifdef CONFIG_PREEMPT_VOLUNTARY
118 extern int _cond_resched(void);
119 # define might_resched() _cond_resched()
121 # define might_resched() do { } while (0)
124 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
125 void __might_sleep(const char *file
, int line
, int preempt_offset
);
127 * might_sleep - annotation for functions that can sleep
129 * this macro will print a stack trace if it is executed in an atomic
130 * context (spinlock, irq-handler, ...).
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
136 # define might_sleep() \
137 do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
139 static inline void __might_sleep(const char *file
, int line
,
140 int preempt_offset
) { }
141 # define might_sleep() do { might_resched(); } while (0)
144 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
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()
154 if (sizeof(x) == sizeof(long)) { \
156 ret = (__x < 0) ? -__x : __x; \
159 ret = (__x < 0) ? -__x : __x; \
164 #define abs64(x) ({ \
166 (__x < 0) ? -__x : __x; \
169 #ifdef CONFIG_PROVE_LOCKING
170 void might_fault(void);
172 static inline void might_fault(void)
178 extern struct atomic_notifier_head panic_notifier_list
;
179 extern long (*panic_blink
)(int state
);
180 NORET_TYPE
void panic(const char * fmt
, ...)
181 __attribute__ ((NORET_AND
format (printf
, 1, 2))) __cold
;
182 extern void oops_enter(void);
183 extern void oops_exit(void);
184 void print_oops_end_marker(void);
185 extern int oops_may_print(void);
186 NORET_TYPE
void do_exit(long error_code
)
188 NORET_TYPE
void complete_and_exit(struct completion
*, long)
190 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
191 extern long simple_strtol(const char *,char **,unsigned int);
192 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
193 extern long long simple_strtoll(const char *,char **,unsigned int);
194 extern int __must_check
strict_strtoul(const char *, unsigned int, unsigned long *);
195 extern int __must_check
strict_strtol(const char *, unsigned int, long *);
196 extern int __must_check
strict_strtoull(const char *, unsigned int, unsigned long long *);
197 extern int __must_check
strict_strtoll(const char *, unsigned int, long long *);
198 extern int sprintf(char * buf
, const char * fmt
, ...)
199 __attribute__ ((format (printf
, 2, 3)));
200 extern int vsprintf(char *buf
, const char *, va_list)
201 __attribute__ ((format (printf
, 2, 0)));
202 extern int snprintf(char * buf
, size_t size
, const char * fmt
, ...)
203 __attribute__ ((format (printf
, 3, 4)));
204 extern int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
205 __attribute__ ((format (printf
, 3, 0)));
206 extern int scnprintf(char * buf
, size_t size
, const char * fmt
, ...)
207 __attribute__ ((format (printf
, 3, 4)));
208 extern int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
209 __attribute__ ((format (printf
, 3, 0)));
210 extern char *kasprintf(gfp_t gfp
, const char *fmt
, ...)
211 __attribute__ ((format (printf
, 2, 3)));
212 extern char *kvasprintf(gfp_t gfp
, const char *fmt
, va_list args
);
214 extern int sscanf(const char *, const char *, ...)
215 __attribute__ ((format (scanf
, 2, 3)));
216 extern int vsscanf(const char *, const char *, va_list)
217 __attribute__ ((format (scanf
, 2, 0)));
219 extern int get_option(char **str
, int *pint
);
220 extern char *get_options(const char *str
, int nints
, int *ints
);
221 extern unsigned long long memparse(const char *ptr
, char **retptr
);
223 extern int core_kernel_text(unsigned long addr
);
224 extern int __kernel_text_address(unsigned long addr
);
225 extern int kernel_text_address(unsigned long addr
);
226 extern int func_ptr_is_kernel_text(void *ptr
);
229 extern struct pid
*session_of_pgrp(struct pid
*pgrp
);
231 unsigned long int_sqrt(unsigned long);
233 extern void bust_spinlocks(int yes
);
234 extern void wake_up_klogd(void);
235 extern int oops_in_progress
; /* If set, an oops, panic(), BUG() or die() is in progress */
236 extern int panic_timeout
;
237 extern int panic_on_oops
;
238 extern int panic_on_unrecovered_nmi
;
239 extern int panic_on_io_nmi
;
240 extern const char *print_tainted(void);
241 extern void add_taint(unsigned flag
);
242 extern int test_taint(unsigned flag
);
243 extern unsigned long get_taint(void);
244 extern int root_mountflags
;
246 extern bool early_boot_irqs_disabled
;
248 /* Values used for system_state */
249 extern enum system_states
{
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
266 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
268 #define TAINT_CRAP 10
269 #define TAINT_FIRMWARE_WORKAROUND 11
271 extern 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]
275 static inline char *pack_hex_byte(char *buf
, u8 byte
)
277 *buf
++ = hex_asc_hi(byte
);
278 *buf
++ = hex_asc_lo(byte
);
282 extern int hex_to_bin(char ch
);
283 extern void hex2bin(u8
*dst
, const char *src
, size_t count
);
286 * General tracing related utility functions - trace_printk(),
287 * tracing_on/tracing_off and tracing_start()/tracing_stop
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.
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.
302 * Most likely, you want to use tracing_on/tracing_off.
304 #ifdef CONFIG_RING_BUFFER
305 void tracing_on(void);
306 void tracing_off(void);
307 /* trace_off_permanent stops recording with no way to bring it back */
308 void tracing_off_permanent(void);
309 int tracing_is_on(void);
311 static inline void tracing_on(void) { }
312 static inline void tracing_off(void) { }
313 static inline void tracing_off_permanent(void) { }
314 static inline int tracing_is_on(void) { return 0; }
317 enum ftrace_dump_mode
{
323 #ifdef CONFIG_TRACING
324 extern void tracing_start(void);
325 extern void tracing_stop(void);
326 extern void ftrace_off_permanent(void);
328 static inline void __attribute__ ((format (printf
, 1, 2)))
329 ____trace_printk_check_format(const char *fmt
, ...)
332 #define __trace_printk_check_format(fmt, args...) \
335 ____trace_printk_check_format(fmt, ##args); \
339 * trace_printk - printf formatting in the ftrace buffer
340 * @fmt: the printf format for printing
342 * Note: __trace_printk is an internal function for trace_printk and
343 * the @ip is passed in via the trace_printk macro.
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.
350 * This is intended as a debugging tool for the developer only.
351 * Please refrain from leaving trace_printks scattered around in
355 #define trace_printk(fmt, args...) \
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; \
363 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
365 __trace_printk(_THIS_IP_, fmt, ##args); \
369 __trace_bprintk(unsigned long ip
, const char *fmt
, ...)
370 __attribute__ ((format (printf
, 2, 3)));
373 __trace_printk(unsigned long ip
, const char *fmt
, ...)
374 __attribute__ ((format (printf
, 2, 3)));
376 extern void trace_dump_stack(void);
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.
383 #define ftrace_vprintk(fmt, vargs) \
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; \
390 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
392 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
396 __ftrace_vbprintk(unsigned long ip
, const char *fmt
, va_list ap
);
399 __ftrace_vprintk(unsigned long ip
, const char *fmt
, va_list ap
);
401 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode
);
404 trace_printk(const char *fmt
, ...) __attribute__ ((format (printf
, 1, 2)));
406 static inline void tracing_start(void) { }
407 static inline void tracing_stop(void) { }
408 static inline void ftrace_off_permanent(void) { }
409 static inline void trace_dump_stack(void) { }
411 trace_printk(const char *fmt
, ...)
416 ftrace_vprintk(const char *fmt
, va_list ap
)
420 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode
) { }
421 #endif /* CONFIG_TRACING */
424 * min()/max()/clamp() macros that also do
425 * strict type-checking.. See the
426 * "unnecessary" pointer comparison.
428 #define min(x, y) ({ \
429 typeof(x) _min1 = (x); \
430 typeof(y) _min2 = (y); \
431 (void) (&_min1 == &_min2); \
432 _min1 < _min2 ? _min1 : _min2; })
434 #define max(x, y) ({ \
435 typeof(x) _max1 = (x); \
436 typeof(y) _max2 = (y); \
437 (void) (&_max1 == &_max2); \
438 _max1 > _max2 ? _max1 : _max2; })
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); })
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); })
459 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
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)); })
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
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.
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; })
487 * ..and if you can't take the strict
488 * types, you can specify one yourself.
490 * Or not use min/max/clamp at all, of course.
492 #define min_t(type, x, y) ({ \
495 __min1 < __min2 ? __min1: __min2; })
497 #define max_t(type, x, y) ({ \
500 __max1 > __max2 ? __max1: __max2; })
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
509 * This macro does no typechecking and uses temporary variables of type
510 * 'type' to make all the comparisons.
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; })
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
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
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; })
539 * swap - swap value of @a and @b
542 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
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.
551 #define container_of(ptr, type, member) ({ \
552 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
553 (type *)( (char *)__mptr - offsetof(type,member) );})
556 extern int do_sysinfo(struct sysinfo
*info
);
558 #endif /* __KERNEL__ */
560 #define SI_LOAD_SHIFT 16
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.. */
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))
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); }))
590 * BUILD_BUG_ON - break compile if a condition is true.
591 * @condition: the condition which the compiler should know is false.
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.
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.
605 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
607 extern int __build_bug_on_failed
;
608 #define BUILD_BUG_ON(condition) \
610 ((void)sizeof(char[1 - 2*!!(condition)])); \
611 if (condition) __build_bug_on_failed = 1; \
615 /* Trap pasters of __FUNCTION__ at compile-time */
616 #define __FUNCTION__ (__func__)
618 /* This helps us to avoid #ifdef CONFIG_NUMA */
625 /* This helps us avoid #ifdef CONFIG_COMPACTION */
626 #ifdef CONFIG_COMPACTION
627 #define COMPACTION_BUILD 1
629 #define COMPACTION_BUILD 0
632 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
633 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
634 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD