xref: /linux-6.15/include/linux/kernel.h (revision a1087ef6)
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) (					\
62 {							\
63 	typeof(y) __y = y;				\
64 	(((x) + (__y - 1)) / __y) * __y;		\
65 }							\
66 )
67 #define rounddown(x, y) (				\
68 {							\
69 	typeof(x) __x = (x);				\
70 	__x - (__x % (y));				\
71 }							\
72 )
73 #define DIV_ROUND_CLOSEST(x, divisor)(			\
74 {							\
75 	typeof(divisor) __divisor = divisor;		\
76 	(((x) + ((__divisor) / 2)) / (__divisor));	\
77 }							\
78 )
79 
80 #define _RET_IP_		(unsigned long)__builtin_return_address(0)
81 #define _THIS_IP_  ({ __label__ __here; __here: (unsigned long)&&__here; })
82 
83 #ifdef CONFIG_LBDAF
84 # include <asm/div64.h>
85 # define sector_div(a, b) do_div(a, b)
86 #else
87 # define sector_div(n, b)( \
88 { \
89 	int _res; \
90 	_res = (n) % (b); \
91 	(n) /= (b); \
92 	_res; \
93 } \
94 )
95 #endif
96 
97 /**
98  * upper_32_bits - return bits 32-63 of a number
99  * @n: the number we're accessing
100  *
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
103  * 32-bits.
104  */
105 #define upper_32_bits(n) ((u32)(((n) >> 16) >> 16))
106 
107 /**
108  * lower_32_bits - return bits 0-31 of a number
109  * @n: the number we're accessing
110  */
111 #define lower_32_bits(n) ((u32)(n))
112 
113 #define	KERN_EMERG	"<0>"	/* system is unusable			*/
114 #define	KERN_ALERT	"<1>"	/* action must be taken immediately	*/
115 #define	KERN_CRIT	"<2>"	/* critical conditions			*/
116 #define	KERN_ERR	"<3>"	/* error conditions			*/
117 #define	KERN_WARNING	"<4>"	/* warning conditions			*/
118 #define	KERN_NOTICE	"<5>"	/* normal but significant condition	*/
119 #define	KERN_INFO	"<6>"	/* informational			*/
120 #define	KERN_DEBUG	"<7>"	/* debug-level messages			*/
121 
122 /* Use the default kernel loglevel */
123 #define KERN_DEFAULT	"<d>"
124 /*
125  * Annotation for a "continued" line of log printout (only done after a
126  * line that had no enclosing \n). Only to be used by core/arch code
127  * during early bootup (a continued line is not SMP-safe otherwise).
128  */
129 #define	KERN_CONT	"<c>"
130 
131 extern int console_printk[];
132 
133 #define console_loglevel (console_printk[0])
134 #define default_message_loglevel (console_printk[1])
135 #define minimum_console_loglevel (console_printk[2])
136 #define default_console_loglevel (console_printk[3])
137 
138 struct completion;
139 struct pt_regs;
140 struct user;
141 
142 #ifdef CONFIG_PREEMPT_VOLUNTARY
143 extern int _cond_resched(void);
144 # define might_resched() _cond_resched()
145 #else
146 # define might_resched() do { } while (0)
147 #endif
148 
149 #ifdef CONFIG_DEBUG_SPINLOCK_SLEEP
150   void __might_sleep(const char *file, int line, int preempt_offset);
151 /**
152  * might_sleep - annotation for functions that can sleep
153  *
154  * this macro will print a stack trace if it is executed in an atomic
155  * context (spinlock, irq-handler, ...).
156  *
157  * This is a useful debugging help to be able to catch problems early and not
158  * be bitten later when the calling function happens to sleep when it is not
159  * supposed to.
160  */
161 # define might_sleep() \
162 	do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0)
163 #else
164   static inline void __might_sleep(const char *file, int line,
165 				   int preempt_offset) { }
166 # define might_sleep() do { might_resched(); } while (0)
167 #endif
168 
169 #define might_sleep_if(cond) do { if (cond) might_sleep(); } while (0)
170 
171 #define abs(x) ({				\
172 		long __x = (x);			\
173 		(__x < 0) ? -__x : __x;		\
174 	})
175 
176 #define abs64(x) ({				\
177 		s64 __x = (x);			\
178 		(__x < 0) ? -__x : __x;		\
179 	})
180 
181 #ifdef CONFIG_PROVE_LOCKING
182 void might_fault(void);
183 #else
184 static inline void might_fault(void)
185 {
186 	might_sleep();
187 }
188 #endif
189 
190 struct va_format {
191 	const char *fmt;
192 	va_list *va;
193 };
194 
195 extern struct atomic_notifier_head panic_notifier_list;
196 extern long (*panic_blink)(int state);
197 NORET_TYPE void panic(const char * fmt, ...)
198 	__attribute__ ((NORET_AND format (printf, 1, 2))) __cold;
199 extern void oops_enter(void);
200 extern void oops_exit(void);
201 void print_oops_end_marker(void);
202 extern int oops_may_print(void);
203 NORET_TYPE void do_exit(long error_code)
204 	ATTRIB_NORET;
205 NORET_TYPE void complete_and_exit(struct completion *, long)
206 	ATTRIB_NORET;
207 extern unsigned long simple_strtoul(const char *,char **,unsigned int);
208 extern long simple_strtol(const char *,char **,unsigned int);
209 extern unsigned long long simple_strtoull(const char *,char **,unsigned int);
210 extern long long simple_strtoll(const char *,char **,unsigned int);
211 extern int __must_check strict_strtoul(const char *, unsigned int, unsigned long *);
212 extern int __must_check strict_strtol(const char *, unsigned int, long *);
213 extern int __must_check strict_strtoull(const char *, unsigned int, unsigned long long *);
214 extern int __must_check strict_strtoll(const char *, unsigned int, long long *);
215 extern int sprintf(char * buf, const char * fmt, ...)
216 	__attribute__ ((format (printf, 2, 3)));
217 extern int vsprintf(char *buf, const char *, va_list)
218 	__attribute__ ((format (printf, 2, 0)));
219 extern int snprintf(char * buf, size_t size, const char * fmt, ...)
220 	__attribute__ ((format (printf, 3, 4)));
221 extern int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
222 	__attribute__ ((format (printf, 3, 0)));
223 extern int scnprintf(char * buf, size_t size, const char * fmt, ...)
224 	__attribute__ ((format (printf, 3, 4)));
225 extern int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
226 	__attribute__ ((format (printf, 3, 0)));
227 extern char *kasprintf(gfp_t gfp, const char *fmt, ...)
228 	__attribute__ ((format (printf, 2, 3)));
229 extern char *kvasprintf(gfp_t gfp, const char *fmt, va_list args);
230 
231 extern int sscanf(const char *, const char *, ...)
232 	__attribute__ ((format (scanf, 2, 3)));
233 extern int vsscanf(const char *, const char *, va_list)
234 	__attribute__ ((format (scanf, 2, 0)));
235 
236 extern int get_option(char **str, int *pint);
237 extern char *get_options(const char *str, int nints, int *ints);
238 extern unsigned long long memparse(const char *ptr, char **retptr);
239 
240 extern int core_kernel_text(unsigned long addr);
241 extern int __kernel_text_address(unsigned long addr);
242 extern int kernel_text_address(unsigned long addr);
243 extern int func_ptr_is_kernel_text(void *ptr);
244 
245 struct pid;
246 extern struct pid *session_of_pgrp(struct pid *pgrp);
247 
248 /*
249  * FW_BUG
250  * Add this to a message where you are sure the firmware is buggy or behaves
251  * really stupid or out of spec. Be aware that the responsible BIOS developer
252  * should be able to fix this issue or at least get a concrete idea of the
253  * problem by reading your message without the need of looking at the kernel
254  * code.
255  *
256  * Use it for definite and high priority BIOS bugs.
257  *
258  * FW_WARN
259  * Use it for not that clear (e.g. could the kernel messed up things already?)
260  * and medium priority BIOS bugs.
261  *
262  * FW_INFO
263  * Use this one if you want to tell the user or vendor about something
264  * suspicious, but generally harmless related to the firmware.
265  *
266  * Use it for information or very low priority BIOS bugs.
267  */
268 #define FW_BUG		"[Firmware Bug]: "
269 #define FW_WARN		"[Firmware Warn]: "
270 #define FW_INFO		"[Firmware Info]: "
271 
272 /*
273  * HW_ERR
274  * Add this to a message for hardware errors, so that user can report
275  * it to hardware vendor instead of LKML or software vendor.
276  */
277 #define HW_ERR		"[Hardware Error]: "
278 
279 #ifdef CONFIG_PRINTK
280 asmlinkage int vprintk(const char *fmt, va_list args)
281 	__attribute__ ((format (printf, 1, 0)));
282 asmlinkage int printk(const char * fmt, ...)
283 	__attribute__ ((format (printf, 1, 2))) __cold;
284 
285 /*
286  * Please don't use printk_ratelimit(), because it shares ratelimiting state
287  * with all other unrelated printk_ratelimit() callsites.  Instead use
288  * printk_ratelimited() or plain old __ratelimit().
289  */
290 extern int __printk_ratelimit(const char *func);
291 #define printk_ratelimit() __printk_ratelimit(__func__)
292 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
293 				   unsigned int interval_msec);
294 
295 extern int printk_delay_msec;
296 
297 /*
298  * Print a one-time message (analogous to WARN_ONCE() et al):
299  */
300 #define printk_once(x...) ({			\
301 	static bool __print_once;		\
302 						\
303 	if (!__print_once) {			\
304 		__print_once = true;		\
305 		printk(x);			\
306 	}					\
307 })
308 
309 void log_buf_kexec_setup(void);
310 #else
311 static inline int vprintk(const char *s, va_list args)
312 	__attribute__ ((format (printf, 1, 0)));
313 static inline int vprintk(const char *s, va_list args) { return 0; }
314 static inline int printk(const char *s, ...)
315 	__attribute__ ((format (printf, 1, 2)));
316 static inline int __cold printk(const char *s, ...) { return 0; }
317 static inline int printk_ratelimit(void) { return 0; }
318 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, \
319 					  unsigned int interval_msec)	\
320 		{ return false; }
321 
322 /* No effect, but we still get type checking even in the !PRINTK case: */
323 #define printk_once(x...) printk(x)
324 
325 static inline void log_buf_kexec_setup(void)
326 {
327 }
328 #endif
329 
330 /*
331  * Dummy printk for disabled debugging statements to use whilst maintaining
332  * gcc's format and side-effect checking.
333  */
334 static inline __attribute__ ((format (printf, 1, 2)))
335 int no_printk(const char *s, ...) { return 0; }
336 
337 extern int printk_needs_cpu(int cpu);
338 extern void printk_tick(void);
339 
340 extern void asmlinkage __attribute__((format(printf, 1, 2)))
341 	early_printk(const char *fmt, ...);
342 
343 unsigned long int_sqrt(unsigned long);
344 
345 static inline void console_silent(void)
346 {
347 	console_loglevel = 0;
348 }
349 
350 static inline void console_verbose(void)
351 {
352 	if (console_loglevel)
353 		console_loglevel = 15;
354 }
355 
356 extern void bust_spinlocks(int yes);
357 extern void wake_up_klogd(void);
358 extern int oops_in_progress;		/* If set, an oops, panic(), BUG() or die() is in progress */
359 extern int panic_timeout;
360 extern int panic_on_oops;
361 extern int panic_on_unrecovered_nmi;
362 extern int panic_on_io_nmi;
363 extern const char *print_tainted(void);
364 extern void add_taint(unsigned flag);
365 extern int test_taint(unsigned flag);
366 extern unsigned long get_taint(void);
367 extern int root_mountflags;
368 
369 /* Values used for system_state */
370 extern enum system_states {
371 	SYSTEM_BOOTING,
372 	SYSTEM_RUNNING,
373 	SYSTEM_HALT,
374 	SYSTEM_POWER_OFF,
375 	SYSTEM_RESTART,
376 	SYSTEM_SUSPEND_DISK,
377 } system_state;
378 
379 #define TAINT_PROPRIETARY_MODULE	0
380 #define TAINT_FORCED_MODULE		1
381 #define TAINT_UNSAFE_SMP		2
382 #define TAINT_FORCED_RMMOD		3
383 #define TAINT_MACHINE_CHECK		4
384 #define TAINT_BAD_PAGE			5
385 #define TAINT_USER			6
386 #define TAINT_DIE			7
387 #define TAINT_OVERRIDDEN_ACPI_TABLE	8
388 #define TAINT_WARN			9
389 #define TAINT_CRAP			10
390 #define TAINT_FIRMWARE_WORKAROUND	11
391 
392 extern void dump_stack(void) __cold;
393 
394 enum {
395 	DUMP_PREFIX_NONE,
396 	DUMP_PREFIX_ADDRESS,
397 	DUMP_PREFIX_OFFSET
398 };
399 extern void hex_dump_to_buffer(const void *buf, size_t len,
400 				int rowsize, int groupsize,
401 				char *linebuf, size_t linebuflen, bool ascii);
402 extern void print_hex_dump(const char *level, const char *prefix_str,
403 				int prefix_type, int rowsize, int groupsize,
404 				const void *buf, size_t len, bool ascii);
405 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
406 			const void *buf, size_t len);
407 
408 extern const char hex_asc[];
409 #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
410 #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
411 
412 static inline char *pack_hex_byte(char *buf, u8 byte)
413 {
414 	*buf++ = hex_asc_hi(byte);
415 	*buf++ = hex_asc_lo(byte);
416 	return buf;
417 }
418 
419 extern int hex_to_bin(char ch);
420 
421 #ifndef pr_fmt
422 #define pr_fmt(fmt) fmt
423 #endif
424 
425 #define pr_emerg(fmt, ...) \
426         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
427 #define pr_alert(fmt, ...) \
428         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
429 #define pr_crit(fmt, ...) \
430         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
431 #define pr_err(fmt, ...) \
432         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
433 #define pr_warning(fmt, ...) \
434         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
435 #define pr_warn pr_warning
436 #define pr_notice(fmt, ...) \
437         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
438 #define pr_info(fmt, ...) \
439         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
440 #define pr_cont(fmt, ...) \
441 	printk(KERN_CONT fmt, ##__VA_ARGS__)
442 
443 /* pr_devel() should produce zero code unless DEBUG is defined */
444 #ifdef DEBUG
445 #define pr_devel(fmt, ...) \
446 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
447 #else
448 #define pr_devel(fmt, ...) \
449 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
450 #endif
451 
452 /* If you are writing a driver, please use dev_dbg instead */
453 #if defined(DEBUG)
454 #define pr_debug(fmt, ...) \
455 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
456 #elif defined(CONFIG_DYNAMIC_DEBUG)
457 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
458 #define pr_debug(fmt, ...) \
459 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
460 #else
461 #define pr_debug(fmt, ...) \
462 	({ if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); 0; })
463 #endif
464 
465 /*
466  * ratelimited messages with local ratelimit_state,
467  * no local ratelimit_state used in the !PRINTK case
468  */
469 #ifdef CONFIG_PRINTK
470 #define printk_ratelimited(fmt, ...)  ({				\
471 	static DEFINE_RATELIMIT_STATE(_rs,				\
472 				      DEFAULT_RATELIMIT_INTERVAL,	\
473 				      DEFAULT_RATELIMIT_BURST);		\
474 									\
475 	if (__ratelimit(&_rs))						\
476 		printk(fmt, ##__VA_ARGS__);				\
477 })
478 #else
479 /* No effect, but we still get type checking even in the !PRINTK case: */
480 #define printk_ratelimited printk
481 #endif
482 
483 #define pr_emerg_ratelimited(fmt, ...) \
484 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
485 #define pr_alert_ratelimited(fmt, ...) \
486 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
487 #define pr_crit_ratelimited(fmt, ...) \
488 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
489 #define pr_err_ratelimited(fmt, ...) \
490 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
491 #define pr_warning_ratelimited(fmt, ...) \
492 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
493 #define pr_warn_ratelimited pr_warning_ratelimited
494 #define pr_notice_ratelimited(fmt, ...) \
495 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
496 #define pr_info_ratelimited(fmt, ...) \
497 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
498 /* no pr_cont_ratelimited, don't do that... */
499 /* If you are writing a driver, please use dev_dbg instead */
500 #if defined(DEBUG)
501 #define pr_debug_ratelimited(fmt, ...) \
502 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
503 #else
504 #define pr_debug_ratelimited(fmt, ...) \
505 	({ if (0) printk_ratelimited(KERN_DEBUG pr_fmt(fmt), \
506 				     ##__VA_ARGS__); 0; })
507 #endif
508 
509 /*
510  * General tracing related utility functions - trace_printk(),
511  * tracing_on/tracing_off and tracing_start()/tracing_stop
512  *
513  * Use tracing_on/tracing_off when you want to quickly turn on or off
514  * tracing. It simply enables or disables the recording of the trace events.
515  * This also corresponds to the user space /sys/kernel/debug/tracing/tracing_on
516  * file, which gives a means for the kernel and userspace to interact.
517  * Place a tracing_off() in the kernel where you want tracing to end.
518  * From user space, examine the trace, and then echo 1 > tracing_on
519  * to continue tracing.
520  *
521  * tracing_stop/tracing_start has slightly more overhead. It is used
522  * by things like suspend to ram where disabling the recording of the
523  * trace is not enough, but tracing must actually stop because things
524  * like calling smp_processor_id() may crash the system.
525  *
526  * Most likely, you want to use tracing_on/tracing_off.
527  */
528 #ifdef CONFIG_RING_BUFFER
529 void tracing_on(void);
530 void tracing_off(void);
531 /* trace_off_permanent stops recording with no way to bring it back */
532 void tracing_off_permanent(void);
533 int tracing_is_on(void);
534 #else
535 static inline void tracing_on(void) { }
536 static inline void tracing_off(void) { }
537 static inline void tracing_off_permanent(void) { }
538 static inline int tracing_is_on(void) { return 0; }
539 #endif
540 
541 enum ftrace_dump_mode {
542 	DUMP_NONE,
543 	DUMP_ALL,
544 	DUMP_ORIG,
545 };
546 
547 #ifdef CONFIG_TRACING
548 extern void tracing_start(void);
549 extern void tracing_stop(void);
550 extern void ftrace_off_permanent(void);
551 
552 static inline void __attribute__ ((format (printf, 1, 2)))
553 ____trace_printk_check_format(const char *fmt, ...)
554 {
555 }
556 #define __trace_printk_check_format(fmt, args...)			\
557 do {									\
558 	if (0)								\
559 		____trace_printk_check_format(fmt, ##args);		\
560 } while (0)
561 
562 /**
563  * trace_printk - printf formatting in the ftrace buffer
564  * @fmt: the printf format for printing
565  *
566  * Note: __trace_printk is an internal function for trace_printk and
567  *       the @ip is passed in via the trace_printk macro.
568  *
569  * This function allows a kernel developer to debug fast path sections
570  * that printk is not appropriate for. By scattering in various
571  * printk like tracing in the code, a developer can quickly see
572  * where problems are occurring.
573  *
574  * This is intended as a debugging tool for the developer only.
575  * Please refrain from leaving trace_printks scattered around in
576  * your code.
577  */
578 
579 #define trace_printk(fmt, args...)					\
580 do {									\
581 	__trace_printk_check_format(fmt, ##args);			\
582 	if (__builtin_constant_p(fmt)) {				\
583 		static const char *trace_printk_fmt			\
584 		  __attribute__((section("__trace_printk_fmt"))) =	\
585 			__builtin_constant_p(fmt) ? fmt : NULL;		\
586 									\
587 		__trace_bprintk(_THIS_IP_, trace_printk_fmt, ##args);	\
588 	} else								\
589 		__trace_printk(_THIS_IP_, fmt, ##args);		\
590 } while (0)
591 
592 extern int
593 __trace_bprintk(unsigned long ip, const char *fmt, ...)
594 	__attribute__ ((format (printf, 2, 3)));
595 
596 extern int
597 __trace_printk(unsigned long ip, const char *fmt, ...)
598 	__attribute__ ((format (printf, 2, 3)));
599 
600 extern void trace_dump_stack(void);
601 
602 /*
603  * The double __builtin_constant_p is because gcc will give us an error
604  * if we try to allocate the static variable to fmt if it is not a
605  * constant. Even with the outer if statement.
606  */
607 #define ftrace_vprintk(fmt, vargs)					\
608 do {									\
609 	if (__builtin_constant_p(fmt)) {				\
610 		static const char *trace_printk_fmt			\
611 		  __attribute__((section("__trace_printk_fmt"))) =	\
612 			__builtin_constant_p(fmt) ? fmt : NULL;		\
613 									\
614 		__ftrace_vbprintk(_THIS_IP_, trace_printk_fmt, vargs);	\
615 	} else								\
616 		__ftrace_vprintk(_THIS_IP_, fmt, vargs);		\
617 } while (0)
618 
619 extern int
620 __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap);
621 
622 extern int
623 __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap);
624 
625 extern void ftrace_dump(enum ftrace_dump_mode oops_dump_mode);
626 #else
627 static inline int
628 trace_printk(const char *fmt, ...) __attribute__ ((format (printf, 1, 2)));
629 
630 static inline void tracing_start(void) { }
631 static inline void tracing_stop(void) { }
632 static inline void ftrace_off_permanent(void) { }
633 static inline void trace_dump_stack(void) { }
634 static inline int
635 trace_printk(const char *fmt, ...)
636 {
637 	return 0;
638 }
639 static inline int
640 ftrace_vprintk(const char *fmt, va_list ap)
641 {
642 	return 0;
643 }
644 static inline void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) { }
645 #endif /* CONFIG_TRACING */
646 
647 /*
648  * min()/max()/clamp() macros that also do
649  * strict type-checking.. See the
650  * "unnecessary" pointer comparison.
651  */
652 #define min(x, y) ({				\
653 	typeof(x) _min1 = (x);			\
654 	typeof(y) _min2 = (y);			\
655 	(void) (&_min1 == &_min2);		\
656 	_min1 < _min2 ? _min1 : _min2; })
657 
658 #define max(x, y) ({				\
659 	typeof(x) _max1 = (x);			\
660 	typeof(y) _max2 = (y);			\
661 	(void) (&_max1 == &_max2);		\
662 	_max1 > _max2 ? _max1 : _max2; })
663 
664 #define min3(x, y, z) ({			\
665 	typeof(x) _min1 = (x);			\
666 	typeof(y) _min2 = (y);			\
667 	typeof(z) _min3 = (z);			\
668 	(void) (&_min1 == &_min2);		\
669 	(void) (&_min1 == &_min3);		\
670 	_min1 < _min2 ? (_min1 < _min3 ? _min1 : _min3) : \
671 		(_min2 < _min3 ? _min2 : _min3); })
672 
673 #define max3(x, y, z) ({			\
674 	typeof(x) _max1 = (x);			\
675 	typeof(y) _max2 = (y);			\
676 	typeof(z) _max3 = (z);			\
677 	(void) (&_max1 == &_max2);		\
678 	(void) (&_max1 == &_max3);		\
679 	_max1 > _max2 ? (_max1 > _max3 ? _max1 : _max3) : \
680 		(_max2 > _max3 ? _max2 : _max3); })
681 
682 /**
683  * min_not_zero - return the minimum that is _not_ zero, unless both are zero
684  * @x: value1
685  * @y: value2
686  */
687 #define min_not_zero(x, y) ({			\
688 	typeof(x) __x = (x);			\
689 	typeof(y) __y = (y);			\
690 	__x == 0 ? __y : ((__y == 0) ? __x : min(__x, __y)); })
691 
692 /**
693  * clamp - return a value clamped to a given range with strict typechecking
694  * @val: current value
695  * @min: minimum allowable value
696  * @max: maximum allowable value
697  *
698  * This macro does strict typechecking of min/max to make sure they are of the
699  * same type as val.  See the unnecessary pointer comparisons.
700  */
701 #define clamp(val, min, max) ({			\
702 	typeof(val) __val = (val);		\
703 	typeof(min) __min = (min);		\
704 	typeof(max) __max = (max);		\
705 	(void) (&__val == &__min);		\
706 	(void) (&__val == &__max);		\
707 	__val = __val < __min ? __min: __val;	\
708 	__val > __max ? __max: __val; })
709 
710 /*
711  * ..and if you can't take the strict
712  * types, you can specify one yourself.
713  *
714  * Or not use min/max/clamp at all, of course.
715  */
716 #define min_t(type, x, y) ({			\
717 	type __min1 = (x);			\
718 	type __min2 = (y);			\
719 	__min1 < __min2 ? __min1: __min2; })
720 
721 #define max_t(type, x, y) ({			\
722 	type __max1 = (x);			\
723 	type __max2 = (y);			\
724 	__max1 > __max2 ? __max1: __max2; })
725 
726 /**
727  * clamp_t - return a value clamped to a given range using a given type
728  * @type: the type of variable to use
729  * @val: current value
730  * @min: minimum allowable value
731  * @max: maximum allowable value
732  *
733  * This macro does no typechecking and uses temporary variables of type
734  * 'type' to make all the comparisons.
735  */
736 #define clamp_t(type, val, min, max) ({		\
737 	type __val = (val);			\
738 	type __min = (min);			\
739 	type __max = (max);			\
740 	__val = __val < __min ? __min: __val;	\
741 	__val > __max ? __max: __val; })
742 
743 /**
744  * clamp_val - return a value clamped to a given range using val's type
745  * @val: current value
746  * @min: minimum allowable value
747  * @max: maximum allowable value
748  *
749  * This macro does no typechecking and uses temporary variables of whatever
750  * type the input argument 'val' is.  This is useful when val is an unsigned
751  * type and min and max are literals that will otherwise be assigned a signed
752  * integer type.
753  */
754 #define clamp_val(val, min, max) ({		\
755 	typeof(val) __val = (val);		\
756 	typeof(val) __min = (min);		\
757 	typeof(val) __max = (max);		\
758 	__val = __val < __min ? __min: __val;	\
759 	__val > __max ? __max: __val; })
760 
761 
762 /*
763  * swap - swap value of @a and @b
764  */
765 #define swap(a, b) \
766 	do { typeof(a) __tmp = (a); (a) = (b); (b) = __tmp; } while (0)
767 
768 /**
769  * container_of - cast a member of a structure out to the containing structure
770  * @ptr:	the pointer to the member.
771  * @type:	the type of the container struct this is embedded in.
772  * @member:	the name of the member within the struct.
773  *
774  */
775 #define container_of(ptr, type, member) ({			\
776 	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
777 	(type *)( (char *)__mptr - offsetof(type,member) );})
778 
779 struct sysinfo;
780 extern int do_sysinfo(struct sysinfo *info);
781 
782 #endif /* __KERNEL__ */
783 
784 #define SI_LOAD_SHIFT	16
785 struct sysinfo {
786 	long uptime;			/* Seconds since boot */
787 	unsigned long loads[3];		/* 1, 5, and 15 minute load averages */
788 	unsigned long totalram;		/* Total usable main memory size */
789 	unsigned long freeram;		/* Available memory size */
790 	unsigned long sharedram;	/* Amount of shared memory */
791 	unsigned long bufferram;	/* Memory used by buffers */
792 	unsigned long totalswap;	/* Total swap space size */
793 	unsigned long freeswap;		/* swap space still available */
794 	unsigned short procs;		/* Number of current processes */
795 	unsigned short pad;		/* explicit padding for m68k */
796 	unsigned long totalhigh;	/* Total high memory size */
797 	unsigned long freehigh;		/* Available high memory size */
798 	unsigned int mem_unit;		/* Memory unit size in bytes */
799 	char _f[20-2*sizeof(long)-sizeof(int)];	/* Padding: libc5 uses this.. */
800 };
801 
802 /* Force a compilation error if condition is true */
803 #define BUILD_BUG_ON(condition) ((void)BUILD_BUG_ON_ZERO(condition))
804 
805 /* Force a compilation error if condition is constant and true */
806 #define MAYBE_BUILD_BUG_ON(cond) ((void)sizeof(char[1 - 2 * !!(cond)]))
807 
808 /* Force a compilation error if a constant expression is not a power of 2 */
809 #define BUILD_BUG_ON_NOT_POWER_OF_2(n)			\
810 	BUILD_BUG_ON((n) == 0 || (((n) & ((n) - 1)) != 0))
811 
812 /* Force a compilation error if condition is true, but also produce a
813    result (of value 0 and type size_t), so the expression can be used
814    e.g. in a structure initializer (or where-ever else comma expressions
815    aren't permitted). */
816 #define BUILD_BUG_ON_ZERO(e) (sizeof(struct { int:-!!(e); }))
817 #define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
818 
819 /* Trap pasters of __FUNCTION__ at compile-time */
820 #define __FUNCTION__ (__func__)
821 
822 /* This helps us to avoid #ifdef CONFIG_NUMA */
823 #ifdef CONFIG_NUMA
824 #define NUMA_BUILD 1
825 #else
826 #define NUMA_BUILD 0
827 #endif
828 
829 /* Rebuild everything on CONFIG_FTRACE_MCOUNT_RECORD */
830 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
831 # define REBUILD_DUE_TO_FTRACE_MCOUNT_RECORD
832 #endif
833 
834 #endif
835