xref: /linux-6.15/include/linux/printk.h (revision c39f472e)
1 #ifndef __KERNEL_PRINTK__
2 #define __KERNEL_PRINTK__
3 
4 #include <stdarg.h>
5 #include <linux/init.h>
6 #include <linux/kern_levels.h>
7 #include <linux/linkage.h>
8 #include <linux/cache.h>
9 
10 extern const char linux_banner[];
11 extern const char linux_proc_banner[];
12 
13 extern char *log_buf_addr_get(void);
14 extern u32 log_buf_len_get(void);
15 
16 static inline int printk_get_level(const char *buffer)
17 {
18 	if (buffer[0] == KERN_SOH_ASCII && buffer[1]) {
19 		switch (buffer[1]) {
20 		case '0' ... '7':
21 		case 'd':	/* KERN_DEFAULT */
22 			return buffer[1];
23 		}
24 	}
25 	return 0;
26 }
27 
28 static inline const char *printk_skip_level(const char *buffer)
29 {
30 	if (printk_get_level(buffer))
31 		return buffer + 2;
32 
33 	return buffer;
34 }
35 
36 /* printk's without a loglevel use this.. */
37 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
38 
39 /* We show everything that is MORE important than this.. */
40 #define CONSOLE_LOGLEVEL_SILENT  0 /* Mum's the word */
41 #define CONSOLE_LOGLEVEL_MIN	 1 /* Minimum loglevel we let people use */
42 #define CONSOLE_LOGLEVEL_QUIET	 4 /* Shhh ..., when booted with "quiet" */
43 #define CONSOLE_LOGLEVEL_DEFAULT 7 /* anything MORE serious than KERN_DEBUG */
44 #define CONSOLE_LOGLEVEL_DEBUG	10 /* issue debug messages */
45 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15	/* You can't shut this one up */
46 
47 extern int console_printk[];
48 
49 #define console_loglevel (console_printk[0])
50 #define default_message_loglevel (console_printk[1])
51 #define minimum_console_loglevel (console_printk[2])
52 #define default_console_loglevel (console_printk[3])
53 
54 static inline void console_silent(void)
55 {
56 	console_loglevel = CONSOLE_LOGLEVEL_SILENT;
57 }
58 
59 static inline void console_verbose(void)
60 {
61 	if (console_loglevel)
62 		console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
63 }
64 
65 struct va_format {
66 	const char *fmt;
67 	va_list *va;
68 };
69 
70 /*
71  * FW_BUG
72  * Add this to a message where you are sure the firmware is buggy or behaves
73  * really stupid or out of spec. Be aware that the responsible BIOS developer
74  * should be able to fix this issue or at least get a concrete idea of the
75  * problem by reading your message without the need of looking at the kernel
76  * code.
77  *
78  * Use it for definite and high priority BIOS bugs.
79  *
80  * FW_WARN
81  * Use it for not that clear (e.g. could the kernel messed up things already?)
82  * and medium priority BIOS bugs.
83  *
84  * FW_INFO
85  * Use this one if you want to tell the user or vendor about something
86  * suspicious, but generally harmless related to the firmware.
87  *
88  * Use it for information or very low priority BIOS bugs.
89  */
90 #define FW_BUG		"[Firmware Bug]: "
91 #define FW_WARN		"[Firmware Warn]: "
92 #define FW_INFO		"[Firmware Info]: "
93 
94 /*
95  * HW_ERR
96  * Add this to a message for hardware errors, so that user can report
97  * it to hardware vendor instead of LKML or software vendor.
98  */
99 #define HW_ERR		"[Hardware Error]: "
100 
101 /*
102  * DEPRECATED
103  * Add this to a message whenever you want to warn user space about the use
104  * of a deprecated aspect of an API so they can stop using it
105  */
106 #define DEPRECATED	"[Deprecated]: "
107 
108 /*
109  * Dummy printk for disabled debugging statements to use whilst maintaining
110  * gcc's format and side-effect checking.
111  */
112 static inline __printf(1, 2)
113 int no_printk(const char *fmt, ...)
114 {
115 	return 0;
116 }
117 
118 #ifdef CONFIG_EARLY_PRINTK
119 extern asmlinkage __printf(1, 2)
120 void early_printk(const char *fmt, ...);
121 #else
122 static inline __printf(1, 2) __cold
123 void early_printk(const char *s, ...) { }
124 #endif
125 
126 typedef int(*printk_func_t)(const char *fmt, va_list args);
127 
128 #ifdef CONFIG_PRINTK
129 asmlinkage __printf(5, 0)
130 int vprintk_emit(int facility, int level,
131 		 const char *dict, size_t dictlen,
132 		 const char *fmt, va_list args);
133 
134 asmlinkage __printf(1, 0)
135 int vprintk(const char *fmt, va_list args);
136 
137 asmlinkage __printf(5, 6) __cold
138 int printk_emit(int facility, int level,
139 		const char *dict, size_t dictlen,
140 		const char *fmt, ...);
141 
142 asmlinkage __printf(1, 2) __cold
143 int printk(const char *fmt, ...);
144 
145 /*
146  * Special printk facility for scheduler/timekeeping use only, _DO_NOT_USE_ !
147  */
148 __printf(1, 2) __cold int printk_deferred(const char *fmt, ...);
149 
150 /*
151  * Please don't use printk_ratelimit(), because it shares ratelimiting state
152  * with all other unrelated printk_ratelimit() callsites.  Instead use
153  * printk_ratelimited() or plain old __ratelimit().
154  */
155 extern int __printk_ratelimit(const char *func);
156 #define printk_ratelimit() __printk_ratelimit(__func__)
157 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
158 				   unsigned int interval_msec);
159 
160 extern int printk_delay_msec;
161 extern int dmesg_restrict;
162 extern int kptr_restrict;
163 
164 extern void wake_up_klogd(void);
165 
166 void log_buf_kexec_setup(void);
167 void __init setup_log_buf(int early);
168 void dump_stack_set_arch_desc(const char *fmt, ...);
169 void dump_stack_print_info(const char *log_lvl);
170 void show_regs_print_info(const char *log_lvl);
171 #else
172 static inline __printf(1, 0)
173 int vprintk(const char *s, va_list args)
174 {
175 	return 0;
176 }
177 static inline __printf(1, 2) __cold
178 int printk(const char *s, ...)
179 {
180 	return 0;
181 }
182 static inline __printf(1, 2) __cold
183 int printk_deferred(const char *s, ...)
184 {
185 	return 0;
186 }
187 static inline int printk_ratelimit(void)
188 {
189 	return 0;
190 }
191 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
192 					  unsigned int interval_msec)
193 {
194 	return false;
195 }
196 
197 static inline void wake_up_klogd(void)
198 {
199 }
200 
201 static inline void log_buf_kexec_setup(void)
202 {
203 }
204 
205 static inline void setup_log_buf(int early)
206 {
207 }
208 
209 static inline void dump_stack_set_arch_desc(const char *fmt, ...)
210 {
211 }
212 
213 static inline void dump_stack_print_info(const char *log_lvl)
214 {
215 }
216 
217 static inline void show_regs_print_info(const char *log_lvl)
218 {
219 }
220 #endif
221 
222 extern asmlinkage void dump_stack(void) __cold;
223 
224 #ifndef pr_fmt
225 #define pr_fmt(fmt) fmt
226 #endif
227 
228 /*
229  * These can be used to print at the various log levels.
230  * All of these will print unconditionally, although note that pr_debug()
231  * and other debug macros are compiled out unless either DEBUG is defined
232  * or CONFIG_DYNAMIC_DEBUG is set.
233  */
234 #define pr_emerg(fmt, ...) \
235 	printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
236 #define pr_alert(fmt, ...) \
237 	printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
238 #define pr_crit(fmt, ...) \
239 	printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
240 #define pr_err(fmt, ...) \
241 	printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
242 #define pr_warning(fmt, ...) \
243 	printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
244 #define pr_warn pr_warning
245 #define pr_notice(fmt, ...) \
246 	printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
247 #define pr_info(fmt, ...) \
248 	printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
249 #define pr_cont(fmt, ...) \
250 	printk(KERN_CONT fmt, ##__VA_ARGS__)
251 
252 /* pr_devel() should produce zero code unless DEBUG is defined */
253 #ifdef DEBUG
254 #define pr_devel(fmt, ...) \
255 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
256 #else
257 #define pr_devel(fmt, ...) \
258 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
259 #endif
260 
261 #include <linux/dynamic_debug.h>
262 
263 /* If you are writing a driver, please use dev_dbg instead */
264 #if defined(CONFIG_DYNAMIC_DEBUG)
265 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
266 #define pr_debug(fmt, ...) \
267 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
268 #elif defined(DEBUG)
269 #define pr_debug(fmt, ...) \
270 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
271 #else
272 #define pr_debug(fmt, ...) \
273 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
274 #endif
275 
276 /*
277  * Print a one-time message (analogous to WARN_ONCE() et al):
278  */
279 
280 #ifdef CONFIG_PRINTK
281 #define printk_once(fmt, ...)					\
282 ({								\
283 	static bool __print_once __read_mostly;			\
284 								\
285 	if (!__print_once) {					\
286 		__print_once = true;				\
287 		printk(fmt, ##__VA_ARGS__);			\
288 	}							\
289 })
290 #define printk_deferred_once(fmt, ...)				\
291 ({								\
292 	static bool __print_once __read_mostly;			\
293 								\
294 	if (!__print_once) {					\
295 		__print_once = true;				\
296 		printk_deferred(fmt, ##__VA_ARGS__);		\
297 	}							\
298 })
299 #else
300 #define printk_once(fmt, ...)					\
301 	no_printk(fmt, ##__VA_ARGS__)
302 #define printk_deferred_once(fmt, ...)				\
303 	no_printk(fmt, ##__VA_ARGS__)
304 #endif
305 
306 #define pr_emerg_once(fmt, ...)					\
307 	printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
308 #define pr_alert_once(fmt, ...)					\
309 	printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
310 #define pr_crit_once(fmt, ...)					\
311 	printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
312 #define pr_err_once(fmt, ...)					\
313 	printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
314 #define pr_warn_once(fmt, ...)					\
315 	printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
316 #define pr_notice_once(fmt, ...)				\
317 	printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
318 #define pr_info_once(fmt, ...)					\
319 	printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
320 #define pr_cont_once(fmt, ...)					\
321 	printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
322 
323 #if defined(DEBUG)
324 #define pr_devel_once(fmt, ...)					\
325 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
326 #else
327 #define pr_devel_once(fmt, ...)					\
328 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
329 #endif
330 
331 /* If you are writing a driver, please use dev_dbg instead */
332 #if defined(DEBUG)
333 #define pr_debug_once(fmt, ...)					\
334 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
335 #else
336 #define pr_debug_once(fmt, ...)					\
337 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
338 #endif
339 
340 /*
341  * ratelimited messages with local ratelimit_state,
342  * no local ratelimit_state used in the !PRINTK case
343  */
344 #ifdef CONFIG_PRINTK
345 #define printk_ratelimited(fmt, ...)					\
346 ({									\
347 	static DEFINE_RATELIMIT_STATE(_rs,				\
348 				      DEFAULT_RATELIMIT_INTERVAL,	\
349 				      DEFAULT_RATELIMIT_BURST);		\
350 									\
351 	if (__ratelimit(&_rs))						\
352 		printk(fmt, ##__VA_ARGS__);				\
353 })
354 #else
355 #define printk_ratelimited(fmt, ...)					\
356 	no_printk(fmt, ##__VA_ARGS__)
357 #endif
358 
359 #define pr_emerg_ratelimited(fmt, ...)					\
360 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
361 #define pr_alert_ratelimited(fmt, ...)					\
362 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
363 #define pr_crit_ratelimited(fmt, ...)					\
364 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
365 #define pr_err_ratelimited(fmt, ...)					\
366 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
367 #define pr_warn_ratelimited(fmt, ...)					\
368 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
369 #define pr_notice_ratelimited(fmt, ...)					\
370 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
371 #define pr_info_ratelimited(fmt, ...)					\
372 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
373 /* no pr_cont_ratelimited, don't do that... */
374 
375 #if defined(DEBUG)
376 #define pr_devel_ratelimited(fmt, ...)					\
377 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
378 #else
379 #define pr_devel_ratelimited(fmt, ...)					\
380 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
381 #endif
382 
383 /* If you are writing a driver, please use dev_dbg instead */
384 #if defined(CONFIG_DYNAMIC_DEBUG)
385 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
386 #define pr_debug_ratelimited(fmt, ...)					\
387 do {									\
388 	static DEFINE_RATELIMIT_STATE(_rs,				\
389 				      DEFAULT_RATELIMIT_INTERVAL,	\
390 				      DEFAULT_RATELIMIT_BURST);		\
391 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
392 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
393 	    __ratelimit(&_rs))						\
394 		__dynamic_pr_debug(&descriptor, fmt, ##__VA_ARGS__);	\
395 } while (0)
396 #elif defined(DEBUG)
397 #define pr_debug_ratelimited(fmt, ...)					\
398 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
399 #else
400 #define pr_debug_ratelimited(fmt, ...) \
401 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
402 #endif
403 
404 extern const struct file_operations kmsg_fops;
405 
406 enum {
407 	DUMP_PREFIX_NONE,
408 	DUMP_PREFIX_ADDRESS,
409 	DUMP_PREFIX_OFFSET
410 };
411 extern void hex_dump_to_buffer(const void *buf, size_t len,
412 			       int rowsize, int groupsize,
413 			       char *linebuf, size_t linebuflen, bool ascii);
414 #ifdef CONFIG_PRINTK
415 extern void print_hex_dump(const char *level, const char *prefix_str,
416 			   int prefix_type, int rowsize, int groupsize,
417 			   const void *buf, size_t len, bool ascii);
418 #if defined(CONFIG_DYNAMIC_DEBUG)
419 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len)	\
420 	dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
421 #else
422 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
423 				 const void *buf, size_t len);
424 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
425 #else
426 static inline void print_hex_dump(const char *level, const char *prefix_str,
427 				  int prefix_type, int rowsize, int groupsize,
428 				  const void *buf, size_t len, bool ascii)
429 {
430 }
431 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
432 					const void *buf, size_t len)
433 {
434 }
435 
436 #endif
437 
438 #if defined(CONFIG_DYNAMIC_DEBUG)
439 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,	\
440 			     groupsize, buf, len, ascii)	\
441 	dynamic_hex_dump(prefix_str, prefix_type, rowsize,	\
442 			 groupsize, buf, len, ascii)
443 #else
444 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,		\
445 			     groupsize, buf, len, ascii)		\
446 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,	\
447 		       groupsize, buf, len, ascii)
448 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
449 
450 #endif
451