xref: /linux-6.15/include/linux/kernel.h (revision 5bf2b193)
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/dynamic_debug.h>
21 #include <asm/byteorder.h>
22 #include <asm/bug.h>
23 
24 extern const char linux_banner[];
25 extern const char linux_proc_banner[];
26 
27 #define USHRT_MAX	((u16)(~0U))
28 #define SHRT_MAX	((s16)(USHRT_MAX>>1))
29 #define SHRT_MIN	((s16)(-SHRT_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)
39 
40 #define STACK_MAGIC	0xdeadbeef
41 
42 #define ALIGN(x, a)		__ALIGN_KERNEL((x), (a))
43 #define __ALIGN_MASK(x, mask)	__ALIGN_KERNEL_MASK((x), (mask))
44 #define PTR_ALIGN(p, a)		((typeof(p))ALIGN((unsigned long)(p), (a)))
45 #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)
46 
47 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
48 
49 /*
50  * This looks more complex than it should be. But we need to
51  * get the type for the ~ right in round_down (it needs to be
52  * as wide as the result!), and we want to evaluate the macro
53  * arguments just once each.
54  */
55 #define __round_mask(x, y) ((__typeof__(x))((y)-1))
56 #define round_up(x, y) ((((x)-1) | __round_mask(x, y))+1)
57 #define round_down(x, y) ((x) & ~__round_mask(x, y))
58 
59 #define FIELD_SIZEOF(t, f) (sizeof(((t*)0)->f))
60 #define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
61 #define roundup(x, y) ((((x) + ((y) - 1)) / (y)) * (y))
62 #define DIV_ROUND_CLOSEST(x, divisor)(			\
63 {							\
64 	typeof(divisor) __divisor = divisor;		\
65 	(((x) + ((__divisor) / 2)) / (__divisor));	\
66 }							\
67 )
68 
69 #define _RET_IP_		(unsigned long)__builtin_return_address(0)
70 #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
71 
72 #ifdef CONFIG_LBDAF
73 # include <asm/div64.h>
74 # define sector_div(a, b) do_div(a, b)
75 #else
76 # define sector_div(n, b)( \
77 { \
78 	int _res; \
79 	_res = (n) % (b); \
80 	(n) /= (b); \
81 	_res; \
82 } \
83 )
84 #endif
85 
86 /**
87  * upper_32_bits - return bits 32-63 of a number
88  * @n: the number we're accessing
89  *
90  * A basic shift-right of a 64- or 32-bit quantity.  Use this to suppress
91  * the "right shift count >= width of type" warning when that quantity is
92  * 32-bits.
93  */
94 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
95 
96 /**
97  * lower_32_bits - return bits 0-31 of a number
98  * @n: the number we're accessing
99  */
100 #define lower_32_bits(n) ((u32)(n))
101 
102 #define	KERN_EMERG	"<0>"	/* system is unusable			*/
103 #define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
104 #define	KERN_CRIT	"<2>"	/* critical conditions			*/
105 #define	KERN_ERR	"<3>"	/* error conditions			*/
106 #define	KERN_WARNING	"<4>"	/* warning conditions			*/
107 #define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
108 #define	KERN_INFO	"<6>"	/* informational			*/
109 #define	KERN_DEBUG	"<7>"	/* debug-level messages			*/
110 
111 /* Use the default kernel loglevel */
112 #define KERN_DEFAULT	"<d>"
113 /*
114  * Annotation for a "continued" line of log printout (only done after a
115  * line that had no enclosing \n). Only to be used by core/arch code
116  * during early bootup (a continued line is not SMP-safe otherwise).
117  */
118 #define	KERN_CONT	"<c>"
119 
120 extern int console_printk[];
121 
122 #define console_loglevel (console_printk[0])
123 #define default_message_loglevel (console_printk[1])
124 #define minimum_console_loglevel (console_printk[2])
125 #define default_console_loglevel (console_printk[3])
126 
127 struct completion;
128 struct pt_regs;
129 struct user;
130 
131 #ifdef CONFIG_PREEMPT_VOLUNTARY
132 extern int _cond_resched(void);
133 # define might_resched() _cond_resched()
134 #else
135 # define might_resched() do { } while (0)
136 #endif
137 
138 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
139   void __might_sleep(const char *file, int line, int preempt_offset);
140 /**
141  * might_sleep - annotation for functions that can sleep
142  *
143  * this macro will print a stack trace if it is executed in an atomic
144  * context (spinlock, irq-handler, ...).
145  *
146  * This is a useful debugging help to be able to catch problems early and not
147  * be bitten later when the calling function happens to sleep when it is not
148  * supposed to.
149  */
150 # define might_sleep() \
151 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
152 #else
153   static inline void __might_sleep(const char *file, int line,
154 				   int preempt_offset) { }
155 # define might_sleep() do { might_resched(); } while (0)
156 #endif
157 
158 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
159 
160 #define abs(x) ({				\
161 		long __x = (x);			\
162 		(__x < 0) ? -__x : __x;		\
163 	})
164 
165 #ifdef CONFIG_PROVE_LOCKING
166 void might_fault(void);
167 #else
168 static inline void might_fault(void)
169 {
170 	might_sleep();
171 }
172 #endif
173 
174 struct va_format {
175 	const char *fmt;
176 	va_list *va;
177 };
178 
179 extern struct atomic_notifier_head panic_notifier_list;
180 extern long (*panic_blink)(int state);
181 NORET_TYPE void panic(const char * fmt, ...)
182 	__attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
183 extern void oops_enter(void);
184 extern void oops_exit(void);
185 void print_oops_end_marker(void);
186 extern int oops_may_print(void);
187 NORET_TYPE void do_exit(long error_code)
188 	ATTRIB_NORET;
189 NORET_TYPE void complete_and_exit(struct completion *, long)
190 	ATTRIB_NORET;
191 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
192 extern long simple_strtol(const char *,char **,unsigned int);
193 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
194 extern long long simple_strtoll(const char *,char **,unsigned int);
195 extern int strict_strtoul(const char *, unsigned int, unsigned long *);
196 extern int strict_strtol(const char *, unsigned int, long *);
197 extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
198 extern int strict_strtoll(const char *, unsigned int, long long *);
199 extern int sprintf(char * buf, const char * fmt, ...)
200 	__attribute__ ((format (printf, 2, 3)));
201 extern int vsprintf(char *buf, const char *, va_list)
202 	__attribute__ ((format (printf, 2, 0)));
203 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
204 	__attribute__ ((format (printf, 3, 4)));
205 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
206 	__attribute__ ((format (printf, 3, 0)));
207 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
208 	__attribute__ ((format (printf, 3, 4)));
209 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
210 	__attribute__ ((format (printf, 3, 0)));
211 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
212 	__attribute__ ((format (printf, 2, 3)));
213 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
214 
215 extern int sscanf(const char *, const char *, ...)
216 	__attribute__ ((format (scanf, 2, 3)));
217 extern int vsscanf(const char *, const char *, va_list)
218 	__attribute__ ((format (scanf, 2, 0)));
219 
220 extern int get_option(char **str, int *pint);
221 extern char *get_options(const char *str, int nints, int *ints);
222 extern unsigned long long memparse(const char *ptr, char **retptr);
223 
224 extern int core_kernel_text(unsigned long addr);
225 extern int __kernel_text_address(unsigned long addr);
226 extern int kernel_text_address(unsigned long addr);
227 extern int func_ptr_is_kernel_text(void *ptr);
228 
229 struct pid;
230 extern struct pid *session_of_pgrp(struct pid *pgrp);
231 
232 /*
233  * FW_BUG
234  * Add this to a message where you are sure the firmware is buggy or behaves
235  * really stupid or out of spec. Be aware that the responsible BIOS developer
236  * should be able to fix this issue or at least get a concrete idea of the
237  * problem by reading your message without the need of looking at the kernel
238  * code.
239  *
240  * Use it for definite and high priority BIOS bugs.
241  *
242  * FW_WARN
243  * Use it for not that clear (e.g. could the kernel messed up things already?)
244  * and medium priority BIOS bugs.
245  *
246  * FW_INFO
247  * Use this one if you want to tell the user or vendor about something
248  * suspicious, but generally harmless related to the firmware.
249  *
250  * Use it for information or very low priority BIOS bugs.
251  */
252 #define FW_BUG		"[Firmware Bug]: "
253 #define FW_WARN		"[Firmware Warn]: "
254 #define FW_INFO		"[Firmware Info]: "
255 
256 /*
257  * HW_ERR
258  * Add this to a message for hardware errors, so that user can report
259  * it to hardware vendor instead of LKML or software vendor.
260  */
261 #define HW_ERR		"[Hardware Error]: "
262 
263 #ifdef CONFIG_PRINTK
264 asmlinkage int vprintk(const char *fmt, va_list args)
265 	__attribute__ ((format (printf, 1, 0)));
266 asmlinkage int printk(const char * fmt, ...)
267 	__attribute__ ((format (printf, 1, 2))) __cold;
268 
269 extern int __printk_ratelimit(const char *func);
270 #define printk_ratelimit() __printk_ratelimit(__func__)
271 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
272 				   unsigned int interval_msec);
273 
274 extern int printk_delay_msec;
275 
276 /*
277  * Print a one-time message (analogous to WARN_ONCE() et al):
278  */
279 #define printk_once(x...) ({			\
280 	static bool __print_once;		\
281 						\
282 	if (!__print_once) {			\
283 		__print_once = true;		\
284 		printk(x);			\
285 	}					\
286 })
287 
288 void log_buf_kexec_setup(void);
289 #else
290 static inline int vprintk(const char *s, va_list args)
291 	__attribute__ ((format (printf, 1, 0)));
292 static inline int vprintk(const char *s, va_list args) { return 0; }
293 static inline int printk(const char *s, ...)
294 	__attribute__ ((format (printf, 1, 2)));
295 static inline int __cold printk(const char *s, ...) { return 0; }
296 static inline int printk_ratelimit(void) { return 0; }
297 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
298 					  unsigned int interval_msec)	\
299 		{ return false; }
300 
301 /* No effect, but we still get type checking even in the !PRINTK case: */
302 #define printk_once(x...) printk(x)
303 
304 static inline void log_buf_kexec_setup(void)
305 {
306 }
307 #endif
308 
309 extern int printk_needs_cpu(int cpu);
310 extern void printk_tick(void);
311 
312 extern void asmlinkage __attribute__((format(printf, 1, 2)))
313 	early_printk(const char *fmt, ...);
314 
315 unsigned long int_sqrt(unsigned long);
316 
317 static inline void console_silent(void)
318 {
319 	console_loglevel = 0;
320 }
321 
322 static inline void console_verbose(void)
323 {
324 	if (console_loglevel)
325 		console_loglevel = 15;
326 }
327 
328 extern void bust_spinlocks(int yes);
329 extern void wake_up_klogd(void);
330 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
331 extern int panic_timeout;
332 extern int panic_on_oops;
333 extern int panic_on_unrecovered_nmi;
334 extern int panic_on_io_nmi;
335 extern const char *print_tainted(void);
336 extern void add_taint(unsigned flag);
337 extern int test_taint(unsigned flag);
338 extern unsigned long get_taint(void);
339 extern int root_mountflags;
340 
341 /* Values used for system_state */
342 extern enum system_states {
343 	SYSTEM_BOOTING,
344 	SYSTEM_RUNNING,
345 	SYSTEM_HALT,
346 	SYSTEM_POWER_OFF,
347 	SYSTEM_RESTART,
348 	SYSTEM_SUSPEND_DISK,
349 } system_state;
350 
351 #define TAINT_PROPRIETARY_MODULE	0
352 #define TAINT_FORCED_MODULE		1
353 #define TAINT_UNSAFE_SMP		2
354 #define TAINT_FORCED_RMMOD		3
355 #define TAINT_MACHINE_CHECK		4
356 #define TAINT_BAD_PAGE			5
357 #define TAINT_USER			6
358 #define TAINT_DIE			7
359 #define TAINT_OVERRIDDEN_ACPI_TABLE	8
360 #define TAINT_WARN			9
361 #define TAINT_CRAP			10
362 #define TAINT_FIRMWARE_WORKAROUND	11
363 
364 extern void dump_stack(void) __cold;
365 
366 enum {
367 	DUMP_PREFIX_NONE,
368 	DUMP_PREFIX_ADDRESS,
369 	DUMP_PREFIX_OFFSET
370 };
371 extern void hex_dump_to_buffer(const void *buf, size_t len,
372 				int rowsize, int groupsize,
373 				char *linebuf, size_t linebuflen, bool ascii);
374 extern void print_hex_dump(const char *level, const char *prefix_str,
375 				int prefix_type, int rowsize, int groupsize,
376 				const void *buf, size_t len, bool ascii);
377 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
378 			const void *buf, size_t len);
379 
380 extern const char hex_asc[];
381 #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
382 #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
383 
384 static inline char *pack_hex_byte(char *buf, u8 byte)
385 {
386 	*buf++ = hex_asc_hi(byte);
387 	*buf++ = hex_asc_lo(byte);
388 	return buf;
389 }
390 
391 extern int hex_to_bin(char ch);
392 
393 #ifndef pr_fmt
394 #define pr_fmt(fmt) fmt
395 #endif
396 
397 #define pr_emerg(fmt, ...) \
398         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
399 #define pr_alert(fmt, ...) \
400         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
401 #define pr_crit(fmt, ...) \
402         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
403 #define pr_err(fmt, ...) \
404         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
405 #define pr_warning(fmt, ...) \
406         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
407 #define pr_warn pr_warning
408 #define pr_notice(fmt, ...) \
409         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
410 #define pr_info(fmt, ...) \
411         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
412 #define pr_cont(fmt, ...) \
413 	printk(KERN_CONT fmt, ##__VA_ARGS__)
414 
415 /* pr_devel() should produce zero code unless DEBUG is defined */
416 #ifdef DEBUG
417 #define pr_devel(fmt, ...) \
418 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
419 #else
420 #define pr_devel(fmt, ...) \
421 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
422 #endif
423 
424 /* If you are writing a driver, please use dev_dbg instead */
425 #if defined(DEBUG)
426 #define pr_debug(fmt, ...) \
427 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
428 #elif defined(CONFIG_DYNAMIC_DEBUG)
429 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
430 #define pr_debug(fmt, ...) \
431 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
432 #else
433 #define pr_debug(fmt, ...) \
434 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
435 #endif
436 
437 /*
438  * ratelimited messages with local ratelimit_state,
439  * no local ratelimit_state used in the !PRINTK case
440  */
441 #ifdef CONFIG_PRINTK
442 #define printk_ratelimited(fmt, ...)  ({				\
443 	static DEFINE_RATELIMIT_STATE(_rs,				\
444 				      DEFAULT_RATELIMIT_INTERVAL,	\
445 				      DEFAULT_RATELIMIT_BURST);		\
446 									\
447 	if (__ratelimit(&_rs))						\
448 		printk(fmt, ##__VA_ARGS__);				\
449 })
450 #else
451 /* No effect, but we still get type checking even in the !PRINTK case: */
452 #define printk_ratelimited printk
453 #endif
454 
455 #define pr_emerg_ratelimited(fmt, ...) \
456 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
457 #define pr_alert_ratelimited(fmt, ...) \
458 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
459 #define pr_crit_ratelimited(fmt, ...) \
460 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
461 #define pr_err_ratelimited(fmt, ...) \
462 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
463 #define pr_warning_ratelimited(fmt, ...) \
464 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
465 #define pr_warn_ratelimited pr_warning_ratelimited
466 #define pr_notice_ratelimited(fmt, ...) \
467 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
468 #define pr_info_ratelimited(fmt, ...) \
469 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
470 /* no pr_cont_ratelimited, don't do that... */
471 /* If you are writing a driver, please use dev_dbg instead */
472 #if defined(DEBUG)
473 #define pr_debug_ratelimited(fmt, ...) \
474 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
475 #else
476 #define pr_debug_ratelimited(fmt, ...) \
477 	({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
478 				     ##__VA_ARGS__); 0; })
479 #endif
480 
481 /*
482  * General tracing related utility functions - trace_printk(),
483  * tracing_on/tracing_off and tracing_start()/tracing_stop
484  *
485  * Use tracing_on/tracing_off when you want to quickly turn on or off
486  * tracing. It simply enables or disables the recording of the trace events.
487  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
488  * file, which gives a means for the kernel and userspace to interact.
489  * Place a tracing_off() in the kernel where you want tracing to end.
490  * From user space, examine the trace, and then echo 1 > tracing_on
491  * to continue tracing.
492  *
493  * tracing_stop/tracing_start has slightly more overhead. It is used
494  * by things like suspend to ram where disabling the recording of the
495  * trace is not enough, but tracing must actually stop because things
496  * like calling smp_processor_id() may crash the system.
497  *
498  * Most likely, you want to use tracing_on/tracing_off.
499  */
500 #ifdef CONFIG_RING_BUFFER
501 void tracing_on(void);
502 void tracing_off(void);
503 /* trace_off_permanent stops recording with no way to bring it back */
504 void tracing_off_permanent(void);
505 int tracing_is_on(void);
506 #else
507 static inline void tracing_on(void) { }
508 static inline void tracing_off(void) { }
509 static inline void tracing_off_permanent(void) { }
510 static inline int tracing_is_on(void) { return 0; }
511 #endif
512 
513 enum ftrace_dump_mode {
514 	DUMP_NONE,
515 	DUMP_ALL,
516 	DUMP_ORIG,
517 };
518 
519 #ifdef CONFIG_TRACING
520 extern void tracing_start(void);
521 extern void tracing_stop(void);
522 extern void ftrace_off_permanent(void);
523 
524 static inline void __attribute__ ((format (printf, 1, 2)))
525 ____trace_printk_check_format(const char *fmt, ...)
526 {
527 }
528 #define __trace_printk_check_format(fmt, args...)			\
529 do {									\
530 	if (0)								\
531 		____trace_printk_check_format(fmt, ##args);		\
532 } while (0)
533 
534 /**
535  * trace_printk - printf formatting in the ftrace buffer
536  * @fmt: the printf format for printing
537  *
538  * Note: __trace_printk is an internal function for trace_printk and
539  *       the @ip is passed in via the trace_printk macro.
540  *
541  * This function allows a kernel developer to debug fast path sections
542  * that printk is not appropriate for. By scattering in various
543  * printk like tracing in the code, a developer can quickly see
544  * where problems are occurring.
545  *
546  * This is intended as a debugging tool for the developer only.
547  * Please refrain from leaving trace_printks scattered around in
548  * your code.
549  */
550 
551 #define trace_printk(fmt, args...)					\
552 do {									\
553 	__trace_printk_check_format(fmt, ##args);			\
554 	if (__builtin_constant_p(fmt)) {				\
555 		static const char *trace_printk_fmt			\
556 		  __attribute__((section("__trace_printk_fmt"))) =	\
557 			__builtin_constant_p(fmt) ? fmt : NULL;		\
558 									\
559 		__trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);	\
560 	} else								\
561 		__trace_printk(_THIS_IP_, fmt, ##args);		\
562 } while (0)
563 
564 extern int
565 __trace_bprintk(unsigned long ip, const char *fmt, ...)
566 	__attribute__ ((format (printf, 2, 3)));
567 
568 extern int
569 __trace_printk(unsigned long ip, const char *fmt, ...)
570 	__attribute__ ((format (printf, 2, 3)));
571 
572 extern void trace_dump_stack(void);
573 
574 /*
575  * The double __builtin_constant_p is because gcc will give us an error
576  * if we try to allocate the static variable to fmt if it is not a
577  * constant. Even with the outer if statement.
578  */
579 #define ftrace_vprintk(fmt, vargs)					\
580 do {									\
581 	if (__builtin_constant_p(fmt)) {				\
582 		static const char *trace_printk_fmt			\
583 		  __attribute__((section("__trace_printk_fmt"))) =	\
584 			__builtin_constant_p(fmt) ? fmt : NULL;		\
585 									\
586 		__ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);	\
587 	} else								\
588 		__ftrace_vprintk(_THIS_IP_, fmt, vargs);		\
589 } while (0)
590 
591 extern int
592 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
593 
594 extern int
595 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
596 
597 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
598 #else
599 static inline int
600 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
601 
602 static inline void tracing_start(void) { }
603 static inline void tracing_stop(void) { }
604 static inline void ftrace_off_permanent(void) { }
605 static inline void trace_dump_stack(void) { }
606 static inline int
607 trace_printk(const char *fmt, ...)
608 {
609 	return 0;
610 }
611 static inline int
612 ftrace_vprintk(const char *fmt, va_list ap)
613 {
614 	return 0;
615 }
616 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
617 #endif /* CONFIG_TRACING */
618 
619 /*
620  * min()/max()/clamp() macros that also do
621  * strict type-checking.. See the
622  * "unnecessary" pointer comparison.
623  */
624 #define min(x, y) ({				\
625 	typeof(x) _min1 = (x);			\
626 	typeof(y) _min2 = (y);			\
627 	(void) (&_min1 == &_min2);		\
628 	_min1 < _min2 ? _min1 : _min2; })
629 
630 #define max(x, y) ({				\
631 	typeof(x) _max1 = (x);			\
632 	typeof(y) _max2 = (y);			\
633 	(void) (&_max1 == &_max2);		\
634 	_max1 > _max2 ? _max1 : _max2; })
635 
636 /**
637  * clamp - return a value clamped to a given range with strict typechecking
638  * @val: current value
639  * @min: minimum allowable value
640  * @max: maximum allowable value
641  *
642  * This macro does strict typechecking of min/max to make sure they are of the
643  * same type as val.  See the unnecessary pointer comparisons.
644  */
645 #define clamp(val, min, max) ({			\
646 	typeof(val) __val = (val);		\
647 	typeof(min) __min = (min);		\
648 	typeof(max) __max = (max);		\
649 	(void) (&__val == &__min);		\
650 	(void) (&__val == &__max);		\
651 	__val = __val < __min ? __min: __val;	\
652 	__val > __max ? __max: __val; })
653 
654 /*
655  * ..and if you can't take the strict
656  * types, you can specify one yourself.
657  *
658  * Or not use min/max/clamp at all, of course.
659  */
660 #define min_t(type, x, y) ({			\
661 	type __min1 = (x);			\
662 	type __min2 = (y);			\
663 	__min1 < __min2 ? __min1: __min2; })
664 
665 #define max_t(type, x, y) ({			\
666 	type __max1 = (x);			\
667 	type __max2 = (y);			\
668 	__max1 > __max2 ? __max1: __max2; })
669 
670 /**
671  * clamp_t - return a value clamped to a given range using a given type
672  * @type: the type of variable to use
673  * @val: current value
674  * @min: minimum allowable value
675  * @max: maximum allowable value
676  *
677  * This macro does no typechecking and uses temporary variables of type
678  * 'type' to make all the comparisons.
679  */
680 #define clamp_t(type, val, min, max) ({		\
681 	type __val = (val);			\
682 	type __min = (min);			\
683 	type __max = (max);			\
684 	__val = __val < __min ? __min: __val;	\
685 	__val > __max ? __max: __val; })
686 
687 /**
688  * clamp_val - return a value clamped to a given range using val's type
689  * @val: current value
690  * @min: minimum allowable value
691  * @max: maximum allowable value
692  *
693  * This macro does no typechecking and uses temporary variables of whatever
694  * type the input argument 'val' is.  This is useful when val is an unsigned
695  * type and min and max are literals that will otherwise be assigned a signed
696  * integer type.
697  */
698 #define clamp_val(val, min, max) ({		\
699 	typeof(val) __val = (val);		\
700 	typeof(val) __min = (min);		\
701 	typeof(val) __max = (max);		\
702 	__val = __val < __min ? __min: __val;	\
703 	__val > __max ? __max: __val; })
704 
705 
706 /*
707  * swap - swap value of @a and @b
708  */
709 #define swap(a, b) \
710 	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
711 
712 /**
713  * container_of - cast a member of a structure out to the containing structure
714  * @ptr:	the pointer to the member.
715  * @type:	the type of the container struct this is embedded in.
716  * @member:	the name of the member within the struct.
717  *
718  */
719 #define container_of(ptr, type, member) ({			\
720 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
721 	(type *)( (char *)__mptr - offsetof(type,member) );})
722 
723 struct sysinfo;
724 extern int do_sysinfo(struct sysinfo *info);
725 
726 #endif /* __KERNEL__ */
727 
728 #define SI_LOAD_SHIFT	16
729 struct sysinfo {
730 	long uptime;			/* Seconds since boot */
731 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
732 	unsigned long totalram;		/* Total usable main memory size */
733 	unsigned long freeram;		/* Available memory size */
734 	unsigned long sharedram;	/* Amount of shared memory */
735 	unsigned long bufferram;	/* Memory used by buffers */
736 	unsigned long totalswap;	/* Total swap space size */
737 	unsigned long freeswap;		/* swap space still available */
738 	unsigned short procs;		/* Number of current processes */
739 	unsigned short pad;		/* explicit padding for m68k */
740 	unsigned long totalhigh;	/* Total high memory size */
741 	unsigned long freehigh;		/* Available high memory size */
742 	unsigned int mem_unit;		/* Memory unit size in bytes */
743 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
744 };
745 
746 /* Force a compilation error if condition is true */
747 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
748 
749 /* Force a compilation error if condition is constant and true */
750 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
751 
752 /* Force a compilation error if a constant expression is not a power of 2 */
753 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
754 	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
755 
756 /* Force a compilation error if condition is true, but also produce a
757    result (of value 0 and type size_t), so the expression can be used
758    e.g. in a structure initializer (or where-ever else comma expressions
759    aren't permitted). */
760 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
761 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
762 
763 /* Trap pasters of __FUNCTION__ at compile-time */
764 #define __FUNCTION__ (__func__)
765 
766 /* This helps us to avoid #ifdef CONFIG_NUMA */
767 #ifdef CONFIG_NUMA
768 #define NUMA_BUILD 1
769 #else
770 #define NUMA_BUILD 0
771 #endif
772 
773 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
774 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
775 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
776 #endif
777 
778 #endif
779