xref: /linux-6.15/include/linux/printk.h (revision a5f6ea29)
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 static inline int printk_get_level(const char *buffer)
14 {
15 	if (buffer[0] == KERN_SOH_ASCII && buffer[1]) {
16 		switch (buffer[1]) {
17 		case '0' ... '7':
18 		case 'd':	/* KERN_DEFAULT */
19 			return buffer[1];
20 		}
21 	}
22 	return 0;
23 }
24 
25 static inline const char *printk_skip_level(const char *buffer)
26 {
27 	if (printk_get_level(buffer)) {
28 		switch (buffer[1]) {
29 		case '0' ... '7':
30 		case 'd':	/* KERN_DEFAULT */
31 			return buffer + 2;
32 		}
33 	}
34 	return buffer;
35 }
36 
37 extern int console_printk[];
38 
39 #define console_loglevel (console_printk[0])
40 #define default_message_loglevel (console_printk[1])
41 #define minimum_console_loglevel (console_printk[2])
42 #define default_console_loglevel (console_printk[3])
43 
44 static inline void console_silent(void)
45 {
46 	console_loglevel = 0;
47 }
48 
49 static inline void console_verbose(void)
50 {
51 	if (console_loglevel)
52 		console_loglevel = 15;
53 }
54 
55 struct va_format {
56 	const char *fmt;
57 	va_list *va;
58 };
59 
60 /*
61  * FW_BUG
62  * Add this to a message where you are sure the firmware is buggy or behaves
63  * really stupid or out of spec. Be aware that the responsible BIOS developer
64  * should be able to fix this issue or at least get a concrete idea of the
65  * problem by reading your message without the need of looking at the kernel
66  * code.
67  *
68  * Use it for definite and high priority BIOS bugs.
69  *
70  * FW_WARN
71  * Use it for not that clear (e.g. could the kernel messed up things already?)
72  * and medium priority BIOS bugs.
73  *
74  * FW_INFO
75  * Use this one if you want to tell the user or vendor about something
76  * suspicious, but generally harmless related to the firmware.
77  *
78  * Use it for information or very low priority BIOS bugs.
79  */
80 #define FW_BUG		"[Firmware Bug]: "
81 #define FW_WARN		"[Firmware Warn]: "
82 #define FW_INFO		"[Firmware Info]: "
83 
84 /*
85  * HW_ERR
86  * Add this to a message for hardware errors, so that user can report
87  * it to hardware vendor instead of LKML or software vendor.
88  */
89 #define HW_ERR		"[Hardware Error]: "
90 
91 /*
92  * DEPRECATED
93  * Add this to a message whenever you want to warn user space about the use
94  * of a deprecated aspect of an API so they can stop using it
95  */
96 #define DEPRECATED	"[Deprecated]: "
97 
98 /*
99  * Dummy printk for disabled debugging statements to use whilst maintaining
100  * gcc's format and side-effect checking.
101  */
102 static inline __printf(1, 2)
103 int no_printk(const char *fmt, ...)
104 {
105 	return 0;
106 }
107 
108 #ifdef CONFIG_EARLY_PRINTK
109 extern asmlinkage __printf(1, 2)
110 void early_printk(const char *fmt, ...);
111 void early_vprintk(const char *fmt, va_list ap);
112 #else
113 static inline __printf(1, 2) __cold
114 void early_printk(const char *s, ...) { }
115 #endif
116 
117 #ifdef CONFIG_PRINTK
118 asmlinkage __printf(5, 0)
119 int vprintk_emit(int facility, int level,
120 		 const char *dict, size_t dictlen,
121 		 const char *fmt, va_list args);
122 
123 asmlinkage __printf(1, 0)
124 int vprintk(const char *fmt, va_list args);
125 
126 asmlinkage __printf(5, 6) __cold
127 asmlinkage int printk_emit(int facility, int level,
128 			   const char *dict, size_t dictlen,
129 			   const char *fmt, ...);
130 
131 asmlinkage __printf(1, 2) __cold
132 int printk(const char *fmt, ...);
133 
134 /*
135  * Special printk facility for scheduler use only, _DO_NOT_USE_ !
136  */
137 __printf(1, 2) __cold int printk_sched(const char *fmt, ...);
138 
139 /*
140  * Please don't use printk_ratelimit(), because it shares ratelimiting state
141  * with all other unrelated printk_ratelimit() callsites.  Instead use
142  * printk_ratelimited() or plain old __ratelimit().
143  */
144 extern int __printk_ratelimit(const char *func);
145 #define printk_ratelimit() __printk_ratelimit(__func__)
146 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
147 				   unsigned int interval_msec);
148 
149 extern int printk_delay_msec;
150 extern int dmesg_restrict;
151 extern int kptr_restrict;
152 
153 extern void wake_up_klogd(void);
154 
155 void log_buf_kexec_setup(void);
156 void __init setup_log_buf(int early);
157 void dump_stack_set_arch_desc(const char *fmt, ...);
158 void dump_stack_print_info(const char *log_lvl);
159 void show_regs_print_info(const char *log_lvl);
160 #else
161 static inline __printf(1, 0)
162 int vprintk(const char *s, va_list args)
163 {
164 	return 0;
165 }
166 static inline __printf(1, 2) __cold
167 int printk(const char *s, ...)
168 {
169 	return 0;
170 }
171 static inline __printf(1, 2) __cold
172 int printk_sched(const char *s, ...)
173 {
174 	return 0;
175 }
176 static inline int printk_ratelimit(void)
177 {
178 	return 0;
179 }
180 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
181 					  unsigned int interval_msec)
182 {
183 	return false;
184 }
185 
186 static inline void wake_up_klogd(void)
187 {
188 }
189 
190 static inline void log_buf_kexec_setup(void)
191 {
192 }
193 
194 static inline void setup_log_buf(int early)
195 {
196 }
197 
198 static inline void dump_stack_set_arch_desc(const char *fmt, ...)
199 {
200 }
201 
202 static inline void dump_stack_print_info(const char *log_lvl)
203 {
204 }
205 
206 static inline void show_regs_print_info(const char *log_lvl)
207 {
208 }
209 #endif
210 
211 extern asmlinkage void dump_stack(void) __cold;
212 
213 #ifndef pr_fmt
214 #define pr_fmt(fmt) fmt
215 #endif
216 
217 #define pr_emerg(fmt, ...) \
218 	printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
219 #define pr_alert(fmt, ...) \
220 	printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
221 #define pr_crit(fmt, ...) \
222 	printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
223 #define pr_err(fmt, ...) \
224 	printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
225 #define pr_warning(fmt, ...) \
226 	printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
227 #define pr_warn pr_warning
228 #define pr_notice(fmt, ...) \
229 	printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
230 #define pr_info(fmt, ...) \
231 	printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
232 #define pr_cont(fmt, ...) \
233 	printk(KERN_CONT fmt, ##__VA_ARGS__)
234 
235 /* pr_devel() should produce zero code unless DEBUG is defined */
236 #ifdef DEBUG
237 #define pr_devel(fmt, ...) \
238 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
239 #else
240 #define pr_devel(fmt, ...) \
241 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
242 #endif
243 
244 #include <linux/dynamic_debug.h>
245 
246 /* If you are writing a driver, please use dev_dbg instead */
247 #if defined(CONFIG_DYNAMIC_DEBUG)
248 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
249 #define pr_debug(fmt, ...) \
250 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
251 #elif defined(DEBUG)
252 #define pr_debug(fmt, ...) \
253 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
254 #else
255 #define pr_debug(fmt, ...) \
256 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
257 #endif
258 
259 /*
260  * Print a one-time message (analogous to WARN_ONCE() et al):
261  */
262 
263 #ifdef CONFIG_PRINTK
264 #define printk_once(fmt, ...)					\
265 ({								\
266 	static bool __print_once __read_mostly;			\
267 								\
268 	if (!__print_once) {					\
269 		__print_once = true;				\
270 		printk(fmt, ##__VA_ARGS__);			\
271 	}							\
272 })
273 #else
274 #define printk_once(fmt, ...)					\
275 	no_printk(fmt, ##__VA_ARGS__)
276 #endif
277 
278 #define pr_emerg_once(fmt, ...)					\
279 	printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
280 #define pr_alert_once(fmt, ...)					\
281 	printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
282 #define pr_crit_once(fmt, ...)					\
283 	printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
284 #define pr_err_once(fmt, ...)					\
285 	printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
286 #define pr_warn_once(fmt, ...)					\
287 	printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
288 #define pr_notice_once(fmt, ...)				\
289 	printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
290 #define pr_info_once(fmt, ...)					\
291 	printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
292 #define pr_cont_once(fmt, ...)					\
293 	printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
294 
295 #if defined(DEBUG)
296 #define pr_devel_once(fmt, ...)					\
297 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
298 #else
299 #define pr_devel_once(fmt, ...)					\
300 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
301 #endif
302 
303 /* If you are writing a driver, please use dev_dbg instead */
304 #if defined(DEBUG)
305 #define pr_debug_once(fmt, ...)					\
306 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
307 #else
308 #define pr_debug_once(fmt, ...)					\
309 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
310 #endif
311 
312 /*
313  * ratelimited messages with local ratelimit_state,
314  * no local ratelimit_state used in the !PRINTK case
315  */
316 #ifdef CONFIG_PRINTK
317 #define printk_ratelimited(fmt, ...)					\
318 ({									\
319 	static DEFINE_RATELIMIT_STATE(_rs,				\
320 				      DEFAULT_RATELIMIT_INTERVAL,	\
321 				      DEFAULT_RATELIMIT_BURST);		\
322 									\
323 	if (__ratelimit(&_rs))						\
324 		printk(fmt, ##__VA_ARGS__);				\
325 })
326 #else
327 #define printk_ratelimited(fmt, ...)					\
328 	no_printk(fmt, ##__VA_ARGS__)
329 #endif
330 
331 #define pr_emerg_ratelimited(fmt, ...)					\
332 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
333 #define pr_alert_ratelimited(fmt, ...)					\
334 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
335 #define pr_crit_ratelimited(fmt, ...)					\
336 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
337 #define pr_err_ratelimited(fmt, ...)					\
338 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
339 #define pr_warn_ratelimited(fmt, ...)					\
340 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
341 #define pr_notice_ratelimited(fmt, ...)					\
342 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
343 #define pr_info_ratelimited(fmt, ...)					\
344 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
345 /* no pr_cont_ratelimited, don't do that... */
346 
347 #if defined(DEBUG)
348 #define pr_devel_ratelimited(fmt, ...)					\
349 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
350 #else
351 #define pr_devel_ratelimited(fmt, ...)					\
352 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
353 #endif
354 
355 /* If you are writing a driver, please use dev_dbg instead */
356 #if defined(CONFIG_DYNAMIC_DEBUG)
357 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
358 #define pr_debug_ratelimited(fmt, ...)					\
359 do {									\
360 	static DEFINE_RATELIMIT_STATE(_rs,				\
361 				      DEFAULT_RATELIMIT_INTERVAL,	\
362 				      DEFAULT_RATELIMIT_BURST);		\
363 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
364 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
365 	    __ratelimit(&_rs))						\
366 		__dynamic_pr_debug(&descriptor, fmt, ##__VA_ARGS__);	\
367 } while (0)
368 #elif defined(DEBUG)
369 #define pr_debug_ratelimited(fmt, ...)					\
370 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
371 #else
372 #define pr_debug_ratelimited(fmt, ...) \
373 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
374 #endif
375 
376 extern const struct file_operations kmsg_fops;
377 
378 enum {
379 	DUMP_PREFIX_NONE,
380 	DUMP_PREFIX_ADDRESS,
381 	DUMP_PREFIX_OFFSET
382 };
383 extern void hex_dump_to_buffer(const void *buf, size_t len,
384 			       int rowsize, int groupsize,
385 			       char *linebuf, size_t linebuflen, bool ascii);
386 #ifdef CONFIG_PRINTK
387 extern void print_hex_dump(const char *level, const char *prefix_str,
388 			   int prefix_type, int rowsize, int groupsize,
389 			   const void *buf, size_t len, bool ascii);
390 #if defined(CONFIG_DYNAMIC_DEBUG)
391 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len)	\
392 	dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
393 #else
394 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
395 				 const void *buf, size_t len);
396 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
397 #else
398 static inline void print_hex_dump(const char *level, const char *prefix_str,
399 				  int prefix_type, int rowsize, int groupsize,
400 				  const void *buf, size_t len, bool ascii)
401 {
402 }
403 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
404 					const void *buf, size_t len)
405 {
406 }
407 
408 #endif
409 
410 #if defined(CONFIG_DYNAMIC_DEBUG)
411 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,	\
412 			     groupsize, buf, len, ascii)	\
413 	dynamic_hex_dump(prefix_str, prefix_type, rowsize,	\
414 			 groupsize, buf, len, ascii)
415 #else
416 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,		\
417 			     groupsize, buf, len, ascii)		\
418 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,	\
419 		       groupsize, buf, len, ascii)
420 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
421 
422 #endif
423