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)
148 (__x < 0) ? -__x : __x; \
151 #define abs64(x) ({ \
153 (__x < 0) ? -__x : __x; \
156 #ifdef CONFIG_PROVE_LOCKING
157 void might_fault(void);
159 static inline void might_fault(void)
165 extern struct atomic_notifier_head panic_notifier_list;
166 extern long (*panic_blink)(int state);
167 NORET_TYPE void panic(const char * fmt, ...)
168 __attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
169 extern void oops_enter(void);
170 extern void oops_exit(void);
171 void print_oops_end_marker(void);
172 extern int oops_may_print(void);
173 NORET_TYPE void do_exit(long error_code)
175 NORET_TYPE void complete_and_exit(struct completion *, long)
177 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
178 extern long simple_strtol(const char *,char **,unsigned int);
179 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
180 extern long long simple_strtoll(const char *,char **,unsigned int);
181 extern int __must_check strict_strtoul(const char *, unsigned int, unsigned long *);
182 extern int __must_check strict_strtol(const char *, unsigned int, long *);
183 extern int __must_check strict_strtoull(const char *, unsigned int, unsigned long long *);
184 extern int __must_check strict_strtoll(const char *, unsigned int, long long *);
185 extern int sprintf(char * buf, const char * fmt, ...)
186 __attribute__ ((format (printf, 2, 3)));
187 extern int vsprintf(char *buf, const char *, va_list)
188 __attribute__ ((format (printf, 2, 0)));
189 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
190 __attribute__ ((format (printf, 3, 4)));
191 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
192 __attribute__ ((format (printf, 3, 0)));
193 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
194 __attribute__ ((format (printf, 3, 4)));
195 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
196 __attribute__ ((format (printf, 3, 0)));
197 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
198 __attribute__ ((format (printf, 2, 3)));
199 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
201 extern int sscanf(const char *, const char *, ...)
202 __attribute__ ((format (scanf, 2, 3)));
203 extern int vsscanf(const char *, const char *, va_list)
204 __attribute__ ((format (scanf, 2, 0)));
206 extern int get_option(char **str, int *pint);
207 extern char *get_options(const char *str, int nints, int *ints);
208 extern unsigned long long memparse(const char *ptr, char **retptr);
210 extern int core_kernel_text(unsigned long addr);
211 extern int __kernel_text_address(unsigned long addr);
212 extern int kernel_text_address(unsigned long addr);
213 extern int func_ptr_is_kernel_text(void *ptr);
216 extern struct pid *session_of_pgrp(struct pid *pgrp);
218 unsigned long int_sqrt(unsigned long);
220 extern void bust_spinlocks(int yes);
221 extern void wake_up_klogd(void);
222 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
223 extern int panic_timeout;
224 extern int panic_on_oops;
225 extern int panic_on_unrecovered_nmi;
226 extern int panic_on_io_nmi;
227 extern const char *print_tainted(void);
228 extern void add_taint(unsigned flag);
229 extern int test_taint(unsigned flag);
230 extern unsigned long get_taint(void);
231 extern int root_mountflags;
233 /* Values used for system_state */
234 extern enum system_states {
243 #define TAINT_PROPRIETARY_MODULE 0
244 #define TAINT_FORCED_MODULE 1
245 #define TAINT_UNSAFE_SMP 2
246 #define TAINT_FORCED_RMMOD 3
247 #define TAINT_MACHINE_CHECK 4
248 #define TAINT_BAD_PAGE 5
251 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
253 #define TAINT_CRAP 10
254 #define TAINT_FIRMWARE_WORKAROUND 11
256 extern const char hex_asc[];
257 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
258 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
260 static inline char *pack_hex_byte(char *buf, u8 byte)
262 *buf++ = hex_asc_hi(byte);
263 *buf++ = hex_asc_lo(byte);
267 extern int hex_to_bin(char ch);
268 extern void hex2bin(u8 *dst, const char *src, size_t count);
271 * General tracing related utility functions - trace_printk(),
272 * tracing_on/tracing_off and tracing_start()/tracing_stop
274 * Use tracing_on/tracing_off when you want to quickly turn on or off
275 * tracing. It simply enables or disables the recording of the trace events.
276 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
277 * file, which gives a means for the kernel and userspace to interact.
278 * Place a tracing_off() in the kernel where you want tracing to end.
279 * From user space, examine the trace, and then echo 1 > tracing_on
280 * to continue tracing.
282 * tracing_stop/tracing_start has slightly more overhead. It is used
283 * by things like suspend to ram where disabling the recording of the
284 * trace is not enough, but tracing must actually stop because things
285 * like calling smp_processor_id() may crash the system.
287 * Most likely, you want to use tracing_on/tracing_off.
289 #ifdef CONFIG_RING_BUFFER
290 void tracing_on(void);
291 void tracing_off(void);
292 /* trace_off_permanent stops recording with no way to bring it back */
293 void tracing_off_permanent(void);
294 int tracing_is_on(void);
296 static inline void tracing_on(void) { }
297 static inline void tracing_off(void) { }
298 static inline void tracing_off_permanent(void) { }
299 static inline int tracing_is_on(void) { return 0; }
302 enum ftrace_dump_mode {
308 #ifdef CONFIG_TRACING
309 extern void tracing_start(void);
310 extern void tracing_stop(void);
311 extern void ftrace_off_permanent(void);
313 static inline void __attribute__ ((format (printf, 1, 2)))
314 ____trace_printk_check_format(const char *fmt, ...)
317 #define __trace_printk_check_format(fmt, args...) \
320 ____trace_printk_check_format(fmt, ##args); \
324 * trace_printk - printf formatting in the ftrace buffer
325 * @fmt: the printf format for printing
327 * Note: __trace_printk is an internal function for trace_printk and
328 * the @ip is passed in via the trace_printk macro.
330 * This function allows a kernel developer to debug fast path sections
331 * that printk is not appropriate for. By scattering in various
332 * printk like tracing in the code, a developer can quickly see
333 * where problems are occurring.
335 * This is intended as a debugging tool for the developer only.
336 * Please refrain from leaving trace_printks scattered around in
340 #define trace_printk(fmt, args...) \
342 __trace_printk_check_format(fmt, ##args); \
343 if (__builtin_constant_p(fmt)) { \
344 static const char *trace_printk_fmt \
345 __attribute__((section("__trace_printk_fmt"))) = \
346 __builtin_constant_p(fmt) ? fmt : NULL; \
348 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
350 __trace_printk(_THIS_IP_, fmt, ##args); \
354 __trace_bprintk(unsigned long ip, const char *fmt, ...)
355 __attribute__ ((format (printf, 2, 3)));
358 __trace_printk(unsigned long ip, const char *fmt, ...)
359 __attribute__ ((format (printf, 2, 3)));
361 extern void trace_dump_stack(void);
364 * The double __builtin_constant_p is because gcc will give us an error
365 * if we try to allocate the static variable to fmt if it is not a
366 * constant. Even with the outer if statement.
368 #define ftrace_vprintk(fmt, vargs) \
370 if (__builtin_constant_p(fmt)) { \
371 static const char *trace_printk_fmt \
372 __attribute__((section("__trace_printk_fmt"))) = \
373 __builtin_constant_p(fmt) ? fmt : NULL; \
375 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
377 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
381 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
384 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
386 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
389 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
391 static inline void tracing_start(void) { }
392 static inline void tracing_stop(void) { }
393 static inline void ftrace_off_permanent(void) { }
394 static inline void trace_dump_stack(void) { }
396 trace_printk(const char *fmt, ...)
401 ftrace_vprintk(const char *fmt, va_list ap)
405 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
406 #endif /* CONFIG_TRACING */
409 * min()/max()/clamp() macros that also do
410 * strict type-checking.. See the
411 * "unnecessary" pointer comparison.
413 #define min(x, y) ({ \
414 typeof(x) _min1 = (x); \
415 typeof(y) _min2 = (y); \
416 (void) (&_min1 == &_min2); \
417 _min1 < _min2 ? _min1 : _min2; })
419 #define max(x, y) ({ \
420 typeof(x) _max1 = (x); \
421 typeof(y) _max2 = (y); \
422 (void) (&_max1 == &_max2); \
423 _max1 > _max2 ? _max1 : _max2; })
425 #define min3(x, y, z) ({ \
426 typeof(x) _min1 = (x); \
427 typeof(y) _min2 = (y); \
428 typeof(z) _min3 = (z); \
429 (void) (&_min1 == &_min2); \
430 (void) (&_min1 == &_min3); \
431 _min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
432 (_min2 < _min3 ? _min2 : _min3); })
434 #define max3(x, y, z) ({ \
435 typeof(x) _max1 = (x); \
436 typeof(y) _max2 = (y); \
437 typeof(z) _max3 = (z); \
438 (void) (&_max1 == &_max2); \
439 (void) (&_max1 == &_max3); \
440 _max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
441 (_max2 > _max3 ? _max2 : _max3); })
444 * min_not_zero - return the minimum that is _not_ zero, unless both are zero
448 #define min_not_zero(x, y) ({ \
449 typeof(x) __x = (x); \
450 typeof(y) __y = (y); \
451 __x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
454 * clamp - return a value clamped to a given range with strict typechecking
455 * @val: current value
456 * @min: minimum allowable value
457 * @max: maximum allowable value
459 * This macro does strict typechecking of min/max to make sure they are of the
460 * same type as val. See the unnecessary pointer comparisons.
462 #define clamp(val, min, max) ({ \
463 typeof(val) __val = (val); \
464 typeof(min) __min = (min); \
465 typeof(max) __max = (max); \
466 (void) (&__val == &__min); \
467 (void) (&__val == &__max); \
468 __val = __val < __min ? __min: __val; \
469 __val > __max ? __max: __val; })
472 * ..and if you can't take the strict
473 * types, you can specify one yourself.
475 * Or not use min/max/clamp at all, of course.
477 #define min_t(type, x, y) ({ \
480 __min1 < __min2 ? __min1: __min2; })
482 #define max_t(type, x, y) ({ \
485 __max1 > __max2 ? __max1: __max2; })
488 * clamp_t - return a value clamped to a given range using a given type
489 * @type: the type of variable to use
490 * @val: current value
491 * @min: minimum allowable value
492 * @max: maximum allowable value
494 * This macro does no typechecking and uses temporary variables of type
495 * 'type' to make all the comparisons.
497 #define clamp_t(type, val, min, max) ({ \
498 type __val = (val); \
499 type __min = (min); \
500 type __max = (max); \
501 __val = __val < __min ? __min: __val; \
502 __val > __max ? __max: __val; })
505 * clamp_val - return a value clamped to a given range using val's type
506 * @val: current value
507 * @min: minimum allowable value
508 * @max: maximum allowable value
510 * This macro does no typechecking and uses temporary variables of whatever
511 * type the input argument 'val' is. This is useful when val is an unsigned
512 * type and min and max are literals that will otherwise be assigned a signed
515 #define clamp_val(val, min, max) ({ \
516 typeof(val) __val = (val); \
517 typeof(val) __min = (min); \
518 typeof(val) __max = (max); \
519 __val = __val < __min ? __min: __val; \
520 __val > __max ? __max: __val; })
524 * swap - swap value of @a and @b
527 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
530 * container_of - cast a member of a structure out to the containing structure
531 * @ptr: the pointer to the member.
532 * @type: the type of the container struct this is embedded in.
533 * @member: the name of the member within the struct.
536 #define container_of(ptr, type, member) ({ \
537 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
538 (type *)( (char *)__mptr - offsetof(type,member) );})
541 extern int do_sysinfo(struct sysinfo *info);
543 #endif /* __KERNEL__ */
545 #define SI_LOAD_SHIFT 16
547 long uptime; /* Seconds since boot */
548 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
549 unsigned long totalram; /* Total usable main memory size */
550 unsigned long freeram; /* Available memory size */
551 unsigned long sharedram; /* Amount of shared memory */
552 unsigned long bufferram; /* Memory used by buffers */
553 unsigned long totalswap; /* Total swap space size */
554 unsigned long freeswap; /* swap space still available */
555 unsigned short procs; /* Number of current processes */
556 unsigned short pad; /* explicit padding for m68k */
557 unsigned long totalhigh; /* Total high memory size */
558 unsigned long freehigh; /* Available high memory size */
559 unsigned int mem_unit; /* Memory unit size in bytes */
560 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
563 /* Force a compilation error if condition is true */
564 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
566 /* Force a compilation error if condition is constant and true */
567 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
569 /* Force a compilation error if a constant expression is not a power of 2 */
570 #define BUILD_BUG_ON_NOT_POWER_OF_2(n) \
571 BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
573 /* Force a compilation error if condition is true, but also produce a
574 result (of value 0 and type size_t), so the expression can be used
575 e.g. in a structure initializer (or where-ever else comma expressions
576 aren't permitted). */
577 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
578 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
580 /* Trap pasters of __FUNCTION__ at compile-time */
581 #define __FUNCTION__ (__func__)
583 /* This helps us to avoid #ifdef CONFIG_NUMA */
590 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
591 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
592 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD