1 #ifndef _LINUX_KERNEL_H
2 #define _LINUX_KERNEL_H
5 * 'kernel.h' contains some often-used function prototypes etc
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/ratelimit.h>
19 #include <linux/dynamic_debug.h>
20 #include <asm/byteorder.h>
23 extern const char linux_banner[];
24 extern const char linux_proc_banner[];
26 #define USHORT_MAX ((u16)(~0U))
27 #define SHORT_MAX ((s16)(USHORT_MAX>>1))
28 #define SHORT_MIN (-SHORT_MAX - 1)
29 #define INT_MAX ((int)(~0U>>1))
30 #define INT_MIN (-INT_MAX - 1)
31 #define UINT_MAX (~0U)
32 #define LONG_MAX ((long)(~0UL>>1))
33 #define LONG_MIN (-LONG_MAX - 1)
34 #define ULONG_MAX (~0UL)
35 #define LLONG_MAX ((long long)(~0ULL>>1))
36 #define LLONG_MIN (-LLONG_MAX - 1)
37 #define ULLONG_MAX (~0ULL)
39 #define STACK_MAGIC 0xdeadbeef
41 #define ALIGN(x,a) __ALIGN_MASK(x,(typeof(x))(a)-1)
42 #define __ALIGN_MASK(x,mask) (((x)+(mask))&~(mask))
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))
48 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
49 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
50 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
51 #define DIV_ROUND_CLOSEST(x, divisor)( \
53 typeof(divisor) __divisor = divisor; \
54 (((x) + ((__divisor) / 2)) / (__divisor)); \
58 #define _RET_IP_ (unsigned long)__builtin_return_address(0)
59 #define _THIS_IP_ ({ __label__ __here; __here: (unsigned long)&&__here; })
62 # include <asm/div64.h>
63 # define sector_div(a, b) do_div(a, b)
65 # define sector_div(n, b)( \
76 * upper_32_bits - return bits 32-63 of a number
77 * @n: the number we're accessing
79 * A basic shift-right of a 64- or 32-bit quantity. Use this to suppress
80 * the "right shift count >= width of type" warning when that quantity is
83 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
86 * lower_32_bits - return bits 0-31 of a number
87 * @n: the number we're accessing
89 #define lower_32_bits(n) ((u32)(n))
91 #define KERN_EMERG "<0>" /* system is unusable */
92 #define KERN_ALERT "<1>" /* action must be taken immediately */
93 #define KERN_CRIT "<2>" /* critical conditions */
94 #define KERN_ERR "<3>" /* error conditions */
95 #define KERN_WARNING "<4>" /* warning conditions */
96 #define KERN_NOTICE "<5>" /* normal but significant condition */
97 #define KERN_INFO "<6>" /* informational */
98 #define KERN_DEBUG "<7>" /* debug-level messages */
100 /* Use the default kernel loglevel */
101 #define KERN_DEFAULT "<d>"
103 * Annotation for a "continued" line of log printout (only done after a
104 * line that had no enclosing \n). Only to be used by core/arch code
105 * during early bootup (a continued line is not SMP-safe otherwise).
107 #define KERN_CONT "<c>"
109 extern int console_printk[];
111 #define console_loglevel (console_printk[0])
112 #define default_message_loglevel (console_printk[1])
113 #define minimum_console_loglevel (console_printk[2])
114 #define default_console_loglevel (console_printk[3])
120 #ifdef CONFIG_PREEMPT_VOLUNTARY
121 extern int _cond_resched(void);
122 # define might_resched() _cond_resched()
124 # define might_resched() do { } while (0)
127 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
128 void __might_sleep(char *file, int line);
130 * might_sleep - annotation for functions that can sleep
132 * this macro will print a stack trace if it is executed in an atomic
133 * context (spinlock, irq-handler, ...).
135 * This is a useful debugging help to be able to catch problems early and not
136 * be bitten later when the calling function happens to sleep when it is not
139 # define might_sleep() \
140 do { __might_sleep(__FILE__, __LINE__); might_resched(); } while (0)
142 # define might_sleep() do { might_resched(); } while (0)
145 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
149 (__x < 0) ? -__x : __x; \
152 #ifdef CONFIG_PROVE_LOCKING
153 void might_fault(void);
155 static inline void might_fault(void)
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)
170 NORET_TYPE void complete_and_exit(struct completion *, long)
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);
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)));
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);
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);
211 extern struct pid *session_of_pgrp(struct pid *pgrp);
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
221 * Use it for definite and high priority BIOS bugs.
224 * Use it for not that clear (e.g. could the kernel messed up things already?)
225 * and medium priority BIOS bugs.
228 * Use this one if you want to tell the user or vendor about something
229 * suspicious, but generally harmless related to the firmware.
231 * Use it for information or very low priority BIOS bugs.
233 #define FW_BUG "[Firmware Bug]: "
234 #define FW_WARN "[Firmware Warn]: "
235 #define FW_INFO "[Firmware Info]: "
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;
243 extern struct ratelimit_state printk_ratelimit_state;
244 extern int printk_ratelimit(void);
245 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
246 unsigned int interval_msec);
249 * Print a one-time message (analogous to WARN_ONCE() et al):
251 #define printk_once(x...) ({ \
252 static int __print_once = 1; \
254 if (__print_once) { \
260 void log_buf_kexec_setup(void);
262 static inline int vprintk(const char *s, va_list args)
263 __attribute__ ((format (printf, 1, 0)));
264 static inline int vprintk(const char *s, va_list args) { return 0; }
265 static inline int printk(const char *s, ...)
266 __attribute__ ((format (printf, 1, 2)));
267 static inline int __cold printk(const char *s, ...) { return 0; }
268 static inline int printk_ratelimit(void) { return 0; }
269 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
270 unsigned int interval_msec) \
273 /* No effect, but we still get type checking even in the !PRINTK case: */
274 #define printk_once(x...) printk(x)
276 static inline void log_buf_kexec_setup(void)
281 extern int printk_needs_cpu(int cpu);
282 extern void printk_tick(void);
284 extern void asmlinkage __attribute__((format(printf, 1, 2)))
285 early_printk(const char *fmt, ...);
287 unsigned long int_sqrt(unsigned long);
289 static inline void console_silent(void)
291 console_loglevel = 0;
294 static inline void console_verbose(void)
296 if (console_loglevel)
297 console_loglevel = 15;
300 extern void bust_spinlocks(int yes);
301 extern void wake_up_klogd(void);
302 extern int oops_in_progress; /* If set, an oops, panic(), BUG() or die() is in progress */
303 extern int panic_timeout;
304 extern int panic_on_oops;
305 extern int panic_on_unrecovered_nmi;
306 extern int panic_on_io_nmi;
307 extern const char *print_tainted(void);
308 extern void add_taint(unsigned flag);
309 extern int test_taint(unsigned flag);
310 extern unsigned long get_taint(void);
311 extern int root_mountflags;
313 /* Values used for system_state */
314 extern enum system_states {
323 #define TAINT_PROPRIETARY_MODULE 0
324 #define TAINT_FORCED_MODULE 1
325 #define TAINT_UNSAFE_SMP 2
326 #define TAINT_FORCED_RMMOD 3
327 #define TAINT_MACHINE_CHECK 4
328 #define TAINT_BAD_PAGE 5
331 #define TAINT_OVERRIDDEN_ACPI_TABLE 8
333 #define TAINT_CRAP 10
335 extern void dump_stack(void) __cold;
342 extern void hex_dump_to_buffer(const void *buf, size_t len,
343 int rowsize, int groupsize,
344 char *linebuf, size_t linebuflen, bool ascii);
345 extern void print_hex_dump(const char *level, const char *prefix_str,
346 int prefix_type, int rowsize, int groupsize,
347 const void *buf, size_t len, bool ascii);
348 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
349 const void *buf, size_t len);
351 extern const char hex_asc[];
352 #define hex_asc_lo(x) hex_asc[((x) & 0x0f)]
353 #define hex_asc_hi(x) hex_asc[((x) & 0xf0) >> 4]
355 static inline char *pack_hex_byte(char *buf, u8 byte)
357 *buf++ = hex_asc_hi(byte);
358 *buf++ = hex_asc_lo(byte);
363 #define pr_fmt(fmt) fmt
366 #define pr_emerg(fmt, ...) \
367 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
368 #define pr_alert(fmt, ...) \
369 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
370 #define pr_crit(fmt, ...) \
371 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
372 #define pr_err(fmt, ...) \
373 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
374 #define pr_warning(fmt, ...) \
375 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
376 #define pr_notice(fmt, ...) \
377 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
378 #define pr_info(fmt, ...) \
379 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
380 #define pr_cont(fmt, ...) \
381 printk(KERN_CONT fmt, ##__VA_ARGS__)
383 /* pr_devel() should produce zero code unless DEBUG is defined */
385 #define pr_devel(fmt, ...) \
386 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
388 #define pr_devel(fmt, ...) \
389 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
392 /* If you are writing a driver, please use dev_dbg instead */
394 #define pr_debug(fmt, ...) \
395 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
396 #elif defined(CONFIG_DYNAMIC_DEBUG)
397 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
398 #define pr_debug(fmt, ...) do { \
399 dynamic_pr_debug(fmt, ##__VA_ARGS__); \
402 #define pr_debug(fmt, ...) \
403 ({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
407 * General tracing related utility functions - trace_printk(),
408 * tracing_on/tracing_off and tracing_start()/tracing_stop
410 * Use tracing_on/tracing_off when you want to quickly turn on or off
411 * tracing. It simply enables or disables the recording of the trace events.
412 * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
413 * file, which gives a means for the kernel and userspace to interact.
414 * Place a tracing_off() in the kernel where you want tracing to end.
415 * From user space, examine the trace, and then echo 1 > tracing_on
416 * to continue tracing.
418 * tracing_stop/tracing_start has slightly more overhead. It is used
419 * by things like suspend to ram where disabling the recording of the
420 * trace is not enough, but tracing must actually stop because things
421 * like calling smp_processor_id() may crash the system.
423 * Most likely, you want to use tracing_on/tracing_off.
425 #ifdef CONFIG_RING_BUFFER
426 void tracing_on(void);
427 void tracing_off(void);
428 /* trace_off_permanent stops recording with no way to bring it back */
429 void tracing_off_permanent(void);
430 int tracing_is_on(void);
432 static inline void tracing_on(void) { }
433 static inline void tracing_off(void) { }
434 static inline void tracing_off_permanent(void) { }
435 static inline int tracing_is_on(void) { return 0; }
437 #ifdef CONFIG_TRACING
438 extern void tracing_start(void);
439 extern void tracing_stop(void);
440 extern void ftrace_off_permanent(void);
443 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3);
445 static inline void __attribute__ ((format (printf, 1, 2)))
446 ____trace_printk_check_format(const char *fmt, ...)
449 #define __trace_printk_check_format(fmt, args...) \
452 ____trace_printk_check_format(fmt, ##args); \
456 * trace_printk - printf formatting in the ftrace buffer
457 * @fmt: the printf format for printing
459 * Note: __trace_printk is an internal function for trace_printk and
460 * the @ip is passed in via the trace_printk macro.
462 * This function allows a kernel developer to debug fast path sections
463 * that printk is not appropriate for. By scattering in various
464 * printk like tracing in the code, a developer can quickly see
465 * where problems are occurring.
467 * This is intended as a debugging tool for the developer only.
468 * Please refrain from leaving trace_printks scattered around in
472 #define trace_printk(fmt, args...) \
474 __trace_printk_check_format(fmt, ##args); \
475 if (__builtin_constant_p(fmt)) { \
476 static const char *trace_printk_fmt \
477 __attribute__((section("__trace_printk_fmt"))) = \
478 __builtin_constant_p(fmt) ? fmt : NULL; \
480 __trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args); \
482 __trace_printk(_THIS_IP_, fmt, ##args); \
486 __trace_bprintk(unsigned long ip, const char *fmt, ...)
487 __attribute__ ((format (printf, 2, 3)));
490 __trace_printk(unsigned long ip, const char *fmt, ...)
491 __attribute__ ((format (printf, 2, 3)));
494 * The double __builtin_constant_p is because gcc will give us an error
495 * if we try to allocate the static variable to fmt if it is not a
496 * constant. Even with the outer if statement.
498 #define ftrace_vprintk(fmt, vargs) \
500 if (__builtin_constant_p(fmt)) { \
501 static const char *trace_printk_fmt \
502 __attribute__((section("__trace_printk_fmt"))) = \
503 __builtin_constant_p(fmt) ? fmt : NULL; \
505 __ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs); \
507 __ftrace_vprintk(_THIS_IP_, fmt, vargs); \
511 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
514 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
516 extern void ftrace_dump(void);
519 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) { }
521 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
523 static inline void tracing_start(void) { }
524 static inline void tracing_stop(void) { }
525 static inline void ftrace_off_permanent(void) { }
527 trace_printk(const char *fmt, ...)
532 ftrace_vprintk(const char *fmt, va_list ap)
536 static inline void ftrace_dump(void) { }
537 #endif /* CONFIG_TRACING */
540 * Display an IP address in readable format.
543 #define NIPQUAD(addr) \
544 ((unsigned char *)&addr)[0], \
545 ((unsigned char *)&addr)[1], \
546 ((unsigned char *)&addr)[2], \
547 ((unsigned char *)&addr)[3]
548 #define NIPQUAD_FMT "%u.%u.%u.%u"
551 * min()/max()/clamp() macros that also do
552 * strict type-checking.. See the
553 * "unnecessary" pointer comparison.
555 #define min(x, y) ({ \
556 typeof(x) _min1 = (x); \
557 typeof(y) _min2 = (y); \
558 (void) (&_min1 == &_min2); \
559 _min1 < _min2 ? _min1 : _min2; })
561 #define max(x, y) ({ \
562 typeof(x) _max1 = (x); \
563 typeof(y) _max2 = (y); \
564 (void) (&_max1 == &_max2); \
565 _max1 > _max2 ? _max1 : _max2; })
568 * clamp - return a value clamped to a given range with strict typechecking
569 * @val: current value
570 * @min: minimum allowable value
571 * @max: maximum allowable value
573 * This macro does strict typechecking of min/max to make sure they are of the
574 * same type as val. See the unnecessary pointer comparisons.
576 #define clamp(val, min, max) ({ \
577 typeof(val) __val = (val); \
578 typeof(min) __min = (min); \
579 typeof(max) __max = (max); \
580 (void) (&__val == &__min); \
581 (void) (&__val == &__max); \
582 __val = __val < __min ? __min: __val; \
583 __val > __max ? __max: __val; })
586 * ..and if you can't take the strict
587 * types, you can specify one yourself.
589 * Or not use min/max/clamp at all, of course.
591 #define min_t(type, x, y) ({ \
594 __min1 < __min2 ? __min1: __min2; })
596 #define max_t(type, x, y) ({ \
599 __max1 > __max2 ? __max1: __max2; })
602 * clamp_t - return a value clamped to a given range using a given type
603 * @type: the type of variable to use
604 * @val: current value
605 * @min: minimum allowable value
606 * @max: maximum allowable value
608 * This macro does no typechecking and uses temporary variables of type
609 * 'type' to make all the comparisons.
611 #define clamp_t(type, val, min, max) ({ \
612 type __val = (val); \
613 type __min = (min); \
614 type __max = (max); \
615 __val = __val < __min ? __min: __val; \
616 __val > __max ? __max: __val; })
619 * clamp_val - return a value clamped to a given range using val's type
620 * @val: current value
621 * @min: minimum allowable value
622 * @max: maximum allowable value
624 * This macro does no typechecking and uses temporary variables of whatever
625 * type the input argument 'val' is. This is useful when val is an unsigned
626 * type and min and max are literals that will otherwise be assigned a signed
629 #define clamp_val(val, min, max) ({ \
630 typeof(val) __val = (val); \
631 typeof(val) __min = (min); \
632 typeof(val) __max = (max); \
633 __val = __val < __min ? __min: __val; \
634 __val > __max ? __max: __val; })
638 * swap - swap value of @a and @b
641 do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
644 * container_of - cast a member of a structure out to the containing structure
645 * @ptr: the pointer to the member.
646 * @type: the type of the container struct this is embedded in.
647 * @member: the name of the member within the struct.
650 #define container_of(ptr, type, member) ({ \
651 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
652 (type *)( (char *)__mptr - offsetof(type,member) );})
655 extern int do_sysinfo(struct sysinfo *info);
657 #endif /* __KERNEL__ */
659 #define SI_LOAD_SHIFT 16
661 long uptime; /* Seconds since boot */
662 unsigned long loads[3]; /* 1, 5, and 15 minute load averages */
663 unsigned long totalram; /* Total usable main memory size */
664 unsigned long freeram; /* Available memory size */
665 unsigned long sharedram; /* Amount of shared memory */
666 unsigned long bufferram; /* Memory used by buffers */
667 unsigned long totalswap; /* Total swap space size */
668 unsigned long freeswap; /* swap space still available */
669 unsigned short procs; /* Number of current processes */
670 unsigned short pad; /* explicit padding for m68k */
671 unsigned long totalhigh; /* Total high memory size */
672 unsigned long freehigh; /* Available high memory size */
673 unsigned int mem_unit; /* Memory unit size in bytes */
674 char _f[20-2*sizeof(long)-sizeof(int)]; /* Padding: libc5 uses this.. */
677 /* Force a compilation error if condition is true */
678 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
680 /* Force a compilation error if condition is true, but also produce a
681 result (of value 0 and type size_t), so the expression can be used
682 e.g. in a structure initializer (or where-ever else comma expressions
683 aren't permitted). */
684 #define BUILD_BUG_ON_ZERO(e) (sizeof(char[1 - 2 * !!(e)]) - 1)
686 /* Trap pasters of __FUNCTION__ at compile-time */
687 #define __FUNCTION__ (__func__)
689 /* This helps us to avoid #ifdef CONFIG_NUMA */
696 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
697 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
698 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD