xref: /linux-6.15/include/linux/kernel.h (revision b898cc70)
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)(long time);
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 extern int oops_may_print(void);
186 NORET_TYPE void do_exit(long error_code)
187 	ATTRIB_NORET;
188 NORET_TYPE void complete_and_exit(struct completion *, long)
189 	ATTRIB_NORET;
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 strict_strtoul(const char *, unsigned int, unsigned long *);
195 extern int strict_strtol(const char *, unsigned int, long *);
196 extern int strict_strtoull(const char *, unsigned int, unsigned long long *);
197 extern int 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);
213 
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)));
218 
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);
222 
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);
227 
228 struct pid;
229 extern struct pid *session_of_pgrp(struct pid *pgrp);
230 
231 /*
232  * FW_BUG
233  * Add this to a message where you are sure the firmware is buggy or behaves
234  * really stupid or out of spec. Be aware that the responsible BIOS developer
235  * should be able to fix this issue or at least get a concrete idea of the
236  * problem by reading your message without the need of looking at the kernel
237  * code.
238  *
239  * Use it for definite and high priority BIOS bugs.
240  *
241  * FW_WARN
242  * Use it for not that clear (e.g. could the kernel messed up things already?)
243  * and medium priority BIOS bugs.
244  *
245  * FW_INFO
246  * Use this one if you want to tell the user or vendor about something
247  * suspicious, but generally harmless related to the firmware.
248  *
249  * Use it for information or very low priority BIOS bugs.
250  */
251 #define FW_BUG		"[Firmware Bug]: "
252 #define FW_WARN		"[Firmware Warn]: "
253 #define FW_INFO		"[Firmware Info]: "
254 
255 /*
256  * HW_ERR
257  * Add this to a message for hardware errors, so that user can report
258  * it to hardware vendor instead of LKML or software vendor.
259  */
260 #define HW_ERR		"[Hardware Error]: "
261 
262 #ifdef CONFIG_PRINTK
263 asmlinkage int vprintk(const char *fmt, va_list args)
264 	__attribute__ ((format (printf, 1, 0)));
265 asmlinkage int printk(const char * fmt, ...)
266 	__attribute__ ((format (printf, 1, 2))) __cold;
267 
268 extern int __printk_ratelimit(const char *func);
269 #define printk_ratelimit() __printk_ratelimit(__func__)
270 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
271 				   unsigned int interval_msec);
272 
273 extern int printk_delay_msec;
274 
275 /*
276  * Print a one-time message (analogous to WARN_ONCE() et al):
277  */
278 #define printk_once(x...) ({			\
279 	static bool __print_once;		\
280 						\
281 	if (!__print_once) {			\
282 		__print_once = true;		\
283 		printk(x);			\
284 	}					\
285 })
286 
287 void log_buf_kexec_setup(void);
288 #else
289 static inline int vprintk(const char *s, va_list args)
290 	__attribute__ ((format (printf, 1, 0)));
291 static inline int vprintk(const char *s, va_list args) { return 0; }
292 static inline int printk(const char *s, ...)
293 	__attribute__ ((format (printf, 1, 2)));
294 static inline int __cold printk(const char *s, ...) { return 0; }
295 static inline int printk_ratelimit(void) { return 0; }
296 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
297 					  unsigned int interval_msec)	\
298 		{ return false; }
299 
300 /* No effect, but we still get type checking even in the !PRINTK case: */
301 #define printk_once(x...) printk(x)
302 
303 static inline void log_buf_kexec_setup(void)
304 {
305 }
306 #endif
307 
308 extern int printk_needs_cpu(int cpu);
309 extern void printk_tick(void);
310 
311 extern void asmlinkage __attribute__((format(printf, 1, 2)))
312 	early_printk(const char *fmt, ...);
313 
314 unsigned long int_sqrt(unsigned long);
315 
316 static inline void console_silent(void)
317 {
318 	console_loglevel = 0;
319 }
320 
321 static inline void console_verbose(void)
322 {
323 	if (console_loglevel)
324 		console_loglevel = 15;
325 }
326 
327 extern void bust_spinlocks(int yes);
328 extern void wake_up_klogd(void);
329 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
330 extern int panic_timeout;
331 extern int panic_on_oops;
332 extern int panic_on_unrecovered_nmi;
333 extern int panic_on_io_nmi;
334 extern const char *print_tainted(void);
335 extern void add_taint(unsigned flag);
336 extern int test_taint(unsigned flag);
337 extern unsigned long get_taint(void);
338 extern int root_mountflags;
339 
340 /* Values used for system_state */
341 extern enum system_states {
342 	SYSTEM_BOOTING,
343 	SYSTEM_RUNNING,
344 	SYSTEM_HALT,
345 	SYSTEM_POWER_OFF,
346 	SYSTEM_RESTART,
347 	SYSTEM_SUSPEND_DISK,
348 } system_state;
349 
350 #define TAINT_PROPRIETARY_MODULE	0
351 #define TAINT_FORCED_MODULE		1
352 #define TAINT_UNSAFE_SMP		2
353 #define TAINT_FORCED_RMMOD		3
354 #define TAINT_MACHINE_CHECK		4
355 #define TAINT_BAD_PAGE			5
356 #define TAINT_USER			6
357 #define TAINT_DIE			7
358 #define TAINT_OVERRIDDEN_ACPI_TABLE	8
359 #define TAINT_WARN			9
360 #define TAINT_CRAP			10
361 #define TAINT_FIRMWARE_WORKAROUND	11
362 
363 extern void dump_stack(void) __cold;
364 
365 enum {
366 	DUMP_PREFIX_NONE,
367 	DUMP_PREFIX_ADDRESS,
368 	DUMP_PREFIX_OFFSET
369 };
370 extern void hex_dump_to_buffer(const void *buf, size_t len,
371 				int rowsize, int groupsize,
372 				char *linebuf, size_t linebuflen, bool ascii);
373 extern void print_hex_dump(const char *level, const char *prefix_str,
374 				int prefix_type, int rowsize, int groupsize,
375 				const void *buf, size_t len, bool ascii);
376 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
377 			const void *buf, size_t len);
378 
379 extern const char hex_asc[];
380 #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
381 #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
382 
383 static inline char *pack_hex_byte(char *buf, u8 byte)
384 {
385 	*buf++ = hex_asc_hi(byte);
386 	*buf++ = hex_asc_lo(byte);
387 	return buf;
388 }
389 
390 extern int hex_to_bin(char ch);
391 
392 #ifndef pr_fmt
393 #define pr_fmt(fmt) fmt
394 #endif
395 
396 #define pr_emerg(fmt, ...) \
397         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
398 #define pr_alert(fmt, ...) \
399         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
400 #define pr_crit(fmt, ...) \
401         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
402 #define pr_err(fmt, ...) \
403         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
404 #define pr_warning(fmt, ...) \
405         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
406 #define pr_warn pr_warning
407 #define pr_notice(fmt, ...) \
408         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
409 #define pr_info(fmt, ...) \
410         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
411 #define pr_cont(fmt, ...) \
412 	printk(KERN_CONT fmt, ##__VA_ARGS__)
413 
414 /* pr_devel() should produce zero code unless DEBUG is defined */
415 #ifdef DEBUG
416 #define pr_devel(fmt, ...) \
417 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
418 #else
419 #define pr_devel(fmt, ...) \
420 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
421 #endif
422 
423 /* If you are writing a driver, please use dev_dbg instead */
424 #if defined(DEBUG)
425 #define pr_debug(fmt, ...) \
426 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
427 #elif defined(CONFIG_DYNAMIC_DEBUG)
428 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
429 #define pr_debug(fmt, ...) \
430 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
431 #else
432 #define pr_debug(fmt, ...) \
433 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
434 #endif
435 
436 /*
437  * ratelimited messages with local ratelimit_state,
438  * no local ratelimit_state used in the !PRINTK case
439  */
440 #ifdef CONFIG_PRINTK
441 #define printk_ratelimited(fmt, ...)  ({				\
442 	static DEFINE_RATELIMIT_STATE(_rs,				\
443 				      DEFAULT_RATELIMIT_INTERVAL,	\
444 				      DEFAULT_RATELIMIT_BURST);		\
445 									\
446 	if (__ratelimit(&_rs))						\
447 		printk(fmt, ##__VA_ARGS__);				\
448 })
449 #else
450 /* No effect, but we still get type checking even in the !PRINTK case: */
451 #define printk_ratelimited printk
452 #endif
453 
454 #define pr_emerg_ratelimited(fmt, ...) \
455 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
456 #define pr_alert_ratelimited(fmt, ...) \
457 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
458 #define pr_crit_ratelimited(fmt, ...) \
459 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
460 #define pr_err_ratelimited(fmt, ...) \
461 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
462 #define pr_warning_ratelimited(fmt, ...) \
463 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
464 #define pr_warn_ratelimited pr_warning_ratelimited
465 #define pr_notice_ratelimited(fmt, ...) \
466 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
467 #define pr_info_ratelimited(fmt, ...) \
468 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
469 /* no pr_cont_ratelimited, don't do that... */
470 /* If you are writing a driver, please use dev_dbg instead */
471 #if defined(DEBUG)
472 #define pr_debug_ratelimited(fmt, ...) \
473 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
474 #else
475 #define pr_debug_ratelimited(fmt, ...) \
476 	({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
477 				     ##__VA_ARGS__); 0; })
478 #endif
479 
480 /*
481  * General tracing related utility functions - trace_printk(),
482  * tracing_on/tracing_off and tracing_start()/tracing_stop
483  *
484  * Use tracing_on/tracing_off when you want to quickly turn on or off
485  * tracing. It simply enables or disables the recording of the trace events.
486  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
487  * file, which gives a means for the kernel and userspace to interact.
488  * Place a tracing_off() in the kernel where you want tracing to end.
489  * From user space, examine the trace, and then echo 1 > tracing_on
490  * to continue tracing.
491  *
492  * tracing_stop/tracing_start has slightly more overhead. It is used
493  * by things like suspend to ram where disabling the recording of the
494  * trace is not enough, but tracing must actually stop because things
495  * like calling smp_processor_id() may crash the system.
496  *
497  * Most likely, you want to use tracing_on/tracing_off.
498  */
499 #ifdef CONFIG_RING_BUFFER
500 void tracing_on(void);
501 void tracing_off(void);
502 /* trace_off_permanent stops recording with no way to bring it back */
503 void tracing_off_permanent(void);
504 int tracing_is_on(void);
505 #else
506 static inline void tracing_on(void) { }
507 static inline void tracing_off(void) { }
508 static inline void tracing_off_permanent(void) { }
509 static inline int tracing_is_on(void) { return 0; }
510 #endif
511 
512 enum ftrace_dump_mode {
513 	DUMP_NONE,
514 	DUMP_ALL,
515 	DUMP_ORIG,
516 };
517 
518 #ifdef CONFIG_TRACING
519 extern void tracing_start(void);
520 extern void tracing_stop(void);
521 extern void ftrace_off_permanent(void);
522 
523 static inline void __attribute__ ((format (printf, 1, 2)))
524 ____trace_printk_check_format(const char *fmt, ...)
525 {
526 }
527 #define __trace_printk_check_format(fmt, args...)			\
528 do {									\
529 	if (0)								\
530 		____trace_printk_check_format(fmt, ##args);		\
531 } while (0)
532 
533 /**
534  * trace_printk - printf formatting in the ftrace buffer
535  * @fmt: the printf format for printing
536  *
537  * Note: __trace_printk is an internal function for trace_printk and
538  *       the @ip is passed in via the trace_printk macro.
539  *
540  * This function allows a kernel developer to debug fast path sections
541  * that printk is not appropriate for. By scattering in various
542  * printk like tracing in the code, a developer can quickly see
543  * where problems are occurring.
544  *
545  * This is intended as a debugging tool for the developer only.
546  * Please refrain from leaving trace_printks scattered around in
547  * your code.
548  */
549 
550 #define trace_printk(fmt, args...)					\
551 do {									\
552 	__trace_printk_check_format(fmt, ##args);			\
553 	if (__builtin_constant_p(fmt)) {				\
554 		static const char *trace_printk_fmt			\
555 		  __attribute__((section("__trace_printk_fmt"))) =	\
556 			__builtin_constant_p(fmt) ? fmt : NULL;		\
557 									\
558 		__trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);	\
559 	} else								\
560 		__trace_printk(_THIS_IP_, fmt, ##args);		\
561 } while (0)
562 
563 extern int
564 __trace_bprintk(unsigned long ip, const char *fmt, ...)
565 	__attribute__ ((format (printf, 2, 3)));
566 
567 extern int
568 __trace_printk(unsigned long ip, const char *fmt, ...)
569 	__attribute__ ((format (printf, 2, 3)));
570 
571 extern void trace_dump_stack(void);
572 
573 /*
574  * The double __builtin_constant_p is because gcc will give us an error
575  * if we try to allocate the static variable to fmt if it is not a
576  * constant. Even with the outer if statement.
577  */
578 #define ftrace_vprintk(fmt, vargs)					\
579 do {									\
580 	if (__builtin_constant_p(fmt)) {				\
581 		static const char *trace_printk_fmt			\
582 		  __attribute__((section("__trace_printk_fmt"))) =	\
583 			__builtin_constant_p(fmt) ? fmt : NULL;		\
584 									\
585 		__ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);	\
586 	} else								\
587 		__ftrace_vprintk(_THIS_IP_, fmt, vargs);		\
588 } while (0)
589 
590 extern int
591 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
592 
593 extern int
594 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
595 
596 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
597 #else
598 static inline int
599 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
600 
601 static inline void tracing_start(void) { }
602 static inline void tracing_stop(void) { }
603 static inline void ftrace_off_permanent(void) { }
604 static inline void trace_dump_stack(void) { }
605 static inline int
606 trace_printk(const char *fmt, ...)
607 {
608 	return 0;
609 }
610 static inline int
611 ftrace_vprintk(const char *fmt, va_list ap)
612 {
613 	return 0;
614 }
615 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
616 #endif /* CONFIG_TRACING */
617 
618 /*
619  *      Display an IP address in readable format.
620  */
621 
622 #define NIPQUAD(addr) \
623 	((unsigned char *)&addr)[0], \
624 	((unsigned char *)&addr)[1], \
625 	((unsigned char *)&addr)[2], \
626 	((unsigned char *)&addr)[3]
627 #define NIPQUAD_FMT "%u.%u.%u.%u"
628 
629 /*
630  * min()/max()/clamp() macros that also do
631  * strict type-checking.. See the
632  * "unnecessary" pointer comparison.
633  */
634 #define min(x, y) ({				\
635 	typeof(x) _min1 = (x);			\
636 	typeof(y) _min2 = (y);			\
637 	(void) (&_min1 == &_min2);		\
638 	_min1 < _min2 ? _min1 : _min2; })
639 
640 #define max(x, y) ({				\
641 	typeof(x) _max1 = (x);			\
642 	typeof(y) _max2 = (y);			\
643 	(void) (&_max1 == &_max2);		\
644 	_max1 > _max2 ? _max1 : _max2; })
645 
646 /**
647  * clamp - return a value clamped to a given range with strict typechecking
648  * @val: current value
649  * @min: minimum allowable value
650  * @max: maximum allowable value
651  *
652  * This macro does strict typechecking of min/max to make sure they are of the
653  * same type as val.  See the unnecessary pointer comparisons.
654  */
655 #define clamp(val, min, max) ({			\
656 	typeof(val) __val = (val);		\
657 	typeof(min) __min = (min);		\
658 	typeof(max) __max = (max);		\
659 	(void) (&__val == &__min);		\
660 	(void) (&__val == &__max);		\
661 	__val = __val < __min ? __min: __val;	\
662 	__val > __max ? __max: __val; })
663 
664 /*
665  * ..and if you can't take the strict
666  * types, you can specify one yourself.
667  *
668  * Or not use min/max/clamp at all, of course.
669  */
670 #define min_t(type, x, y) ({			\
671 	type __min1 = (x);			\
672 	type __min2 = (y);			\
673 	__min1 < __min2 ? __min1: __min2; })
674 
675 #define max_t(type, x, y) ({			\
676 	type __max1 = (x);			\
677 	type __max2 = (y);			\
678 	__max1 > __max2 ? __max1: __max2; })
679 
680 /**
681  * clamp_t - return a value clamped to a given range using a given type
682  * @type: the type of variable to use
683  * @val: current value
684  * @min: minimum allowable value
685  * @max: maximum allowable value
686  *
687  * This macro does no typechecking and uses temporary variables of type
688  * 'type' to make all the comparisons.
689  */
690 #define clamp_t(type, val, min, max) ({		\
691 	type __val = (val);			\
692 	type __min = (min);			\
693 	type __max = (max);			\
694 	__val = __val < __min ? __min: __val;	\
695 	__val > __max ? __max: __val; })
696 
697 /**
698  * clamp_val - return a value clamped to a given range using val's type
699  * @val: current value
700  * @min: minimum allowable value
701  * @max: maximum allowable value
702  *
703  * This macro does no typechecking and uses temporary variables of whatever
704  * type the input argument 'val' is.  This is useful when val is an unsigned
705  * type and min and max are literals that will otherwise be assigned a signed
706  * integer type.
707  */
708 #define clamp_val(val, min, max) ({		\
709 	typeof(val) __val = (val);		\
710 	typeof(val) __min = (min);		\
711 	typeof(val) __max = (max);		\
712 	__val = __val < __min ? __min: __val;	\
713 	__val > __max ? __max: __val; })
714 
715 
716 /*
717  * swap - swap value of @a and @b
718  */
719 #define swap(a, b) \
720 	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
721 
722 /**
723  * container_of - cast a member of a structure out to the containing structure
724  * @ptr:	the pointer to the member.
725  * @type:	the type of the container struct this is embedded in.
726  * @member:	the name of the member within the struct.
727  *
728  */
729 #define container_of(ptr, type, member) ({			\
730 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
731 	(type *)( (char *)__mptr - offsetof(type,member) );})
732 
733 struct sysinfo;
734 extern int do_sysinfo(struct sysinfo *info);
735 
736 #endif /* __KERNEL__ */
737 
738 #define SI_LOAD_SHIFT	16
739 struct sysinfo {
740 	long uptime;			/* Seconds since boot */
741 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
742 	unsigned long totalram;		/* Total usable main memory size */
743 	unsigned long freeram;		/* Available memory size */
744 	unsigned long sharedram;	/* Amount of shared memory */
745 	unsigned long bufferram;	/* Memory used by buffers */
746 	unsigned long totalswap;	/* Total swap space size */
747 	unsigned long freeswap;		/* swap space still available */
748 	unsigned short procs;		/* Number of current processes */
749 	unsigned short pad;		/* explicit padding for m68k */
750 	unsigned long totalhigh;	/* Total high memory size */
751 	unsigned long freehigh;		/* Available high memory size */
752 	unsigned int mem_unit;		/* Memory unit size in bytes */
753 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
754 };
755 
756 /* Force a compilation error if condition is true */
757 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
758 
759 /* Force a compilation error if condition is constant and true */
760 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
761 
762 /* Force a compilation error if a constant expression is not a power of 2 */
763 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
764 	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
765 
766 /* Force a compilation error if condition is true, but also produce a
767    result (of value 0 and type size_t), so the expression can be used
768    e.g. in a structure initializer (or where-ever else comma expressions
769    aren't permitted). */
770 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
771 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
772 
773 /* Trap pasters of __FUNCTION__ at compile-time */
774 #define __FUNCTION__ (__func__)
775 
776 /* This helps us to avoid #ifdef CONFIG_NUMA */
777 #ifdef CONFIG_NUMA
778 #define NUMA_BUILD 1
779 #else
780 #define NUMA_BUILD 0
781 #endif
782 
783 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
784 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
785 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
786 #endif
787 
788 #endif
789