xref: /linux-6.15/include/linux/printk.h (revision bb66fc67)
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 		return buffer + 2;
29 
30 	return buffer;
31 }
32 
33 extern int console_printk[];
34 
35 #define console_loglevel (console_printk[0])
36 #define default_message_loglevel (console_printk[1])
37 #define minimum_console_loglevel (console_printk[2])
38 #define default_console_loglevel (console_printk[3])
39 
40 static inline void console_silent(void)
41 {
42 	console_loglevel = 0;
43 }
44 
45 static inline void console_verbose(void)
46 {
47 	if (console_loglevel)
48 		console_loglevel = 15;
49 }
50 
51 struct va_format {
52 	const char *fmt;
53 	va_list *va;
54 };
55 
56 /*
57  * FW_BUG
58  * Add this to a message where you are sure the firmware is buggy or behaves
59  * really stupid or out of spec. Be aware that the responsible BIOS developer
60  * should be able to fix this issue or at least get a concrete idea of the
61  * problem by reading your message without the need of looking at the kernel
62  * code.
63  *
64  * Use it for definite and high priority BIOS bugs.
65  *
66  * FW_WARN
67  * Use it for not that clear (e.g. could the kernel messed up things already?)
68  * and medium priority BIOS bugs.
69  *
70  * FW_INFO
71  * Use this one if you want to tell the user or vendor about something
72  * suspicious, but generally harmless related to the firmware.
73  *
74  * Use it for information or very low priority BIOS bugs.
75  */
76 #define FW_BUG		"[Firmware Bug]: "
77 #define FW_WARN		"[Firmware Warn]: "
78 #define FW_INFO		"[Firmware Info]: "
79 
80 /*
81  * HW_ERR
82  * Add this to a message for hardware errors, so that user can report
83  * it to hardware vendor instead of LKML or software vendor.
84  */
85 #define HW_ERR		"[Hardware Error]: "
86 
87 /*
88  * DEPRECATED
89  * Add this to a message whenever you want to warn user space about the use
90  * of a deprecated aspect of an API so they can stop using it
91  */
92 #define DEPRECATED	"[Deprecated]: "
93 
94 /*
95  * Dummy printk for disabled debugging statements to use whilst maintaining
96  * gcc's format and side-effect checking.
97  */
98 static inline __printf(1, 2)
99 int no_printk(const char *fmt, ...)
100 {
101 	return 0;
102 }
103 
104 #ifdef CONFIG_EARLY_PRINTK
105 extern asmlinkage __printf(1, 2)
106 void early_printk(const char *fmt, ...);
107 void early_vprintk(const char *fmt, va_list ap);
108 #else
109 static inline __printf(1, 2) __cold
110 void early_printk(const char *s, ...) { }
111 #endif
112 
113 #ifdef CONFIG_PRINTK
114 asmlinkage __printf(5, 0)
115 int vprintk_emit(int facility, int level,
116 		 const char *dict, size_t dictlen,
117 		 const char *fmt, va_list args);
118 
119 asmlinkage __printf(1, 0)
120 int vprintk(const char *fmt, va_list args);
121 
122 asmlinkage __printf(5, 6) __cold
123 int printk_emit(int facility, int level,
124 		const char *dict, size_t dictlen,
125 		const char *fmt, ...);
126 
127 asmlinkage __printf(1, 2) __cold
128 int printk(const char *fmt, ...);
129 
130 /*
131  * Special printk facility for scheduler use only, _DO_NOT_USE_ !
132  */
133 __printf(1, 2) __cold int printk_sched(const char *fmt, ...);
134 
135 /*
136  * Please don't use printk_ratelimit(), because it shares ratelimiting state
137  * with all other unrelated printk_ratelimit() callsites.  Instead use
138  * printk_ratelimited() or plain old __ratelimit().
139  */
140 extern int __printk_ratelimit(const char *func);
141 #define printk_ratelimit() __printk_ratelimit(__func__)
142 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
143 				   unsigned int interval_msec);
144 
145 extern int printk_delay_msec;
146 extern int dmesg_restrict;
147 extern int kptr_restrict;
148 
149 extern void wake_up_klogd(void);
150 
151 void log_buf_kexec_setup(void);
152 void __init setup_log_buf(int early);
153 void dump_stack_set_arch_desc(const char *fmt, ...);
154 void dump_stack_print_info(const char *log_lvl);
155 void show_regs_print_info(const char *log_lvl);
156 #else
157 static inline __printf(1, 0)
158 int vprintk(const char *s, va_list args)
159 {
160 	return 0;
161 }
162 static inline __printf(1, 2) __cold
163 int printk(const char *s, ...)
164 {
165 	return 0;
166 }
167 static inline __printf(1, 2) __cold
168 int printk_sched(const char *s, ...)
169 {
170 	return 0;
171 }
172 static inline int printk_ratelimit(void)
173 {
174 	return 0;
175 }
176 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
177 					  unsigned int interval_msec)
178 {
179 	return false;
180 }
181 
182 static inline void wake_up_klogd(void)
183 {
184 }
185 
186 static inline void log_buf_kexec_setup(void)
187 {
188 }
189 
190 static inline void setup_log_buf(int early)
191 {
192 }
193 
194 static inline void dump_stack_set_arch_desc(const char *fmt, ...)
195 {
196 }
197 
198 static inline void dump_stack_print_info(const char *log_lvl)
199 {
200 }
201 
202 static inline void show_regs_print_info(const char *log_lvl)
203 {
204 }
205 #endif
206 
207 extern asmlinkage void dump_stack(void) __cold;
208 
209 #ifndef pr_fmt
210 #define pr_fmt(fmt) fmt
211 #endif
212 
213 #define pr_emerg(fmt, ...) \
214 	printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
215 #define pr_alert(fmt, ...) \
216 	printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
217 #define pr_crit(fmt, ...) \
218 	printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
219 #define pr_err(fmt, ...) \
220 	printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
221 #define pr_warning(fmt, ...) \
222 	printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
223 #define pr_warn pr_warning
224 #define pr_notice(fmt, ...) \
225 	printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
226 #define pr_info(fmt, ...) \
227 	printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
228 #define pr_cont(fmt, ...) \
229 	printk(KERN_CONT fmt, ##__VA_ARGS__)
230 
231 /* pr_devel() should produce zero code unless DEBUG is defined */
232 #ifdef DEBUG
233 #define pr_devel(fmt, ...) \
234 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
235 #else
236 #define pr_devel(fmt, ...) \
237 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
238 #endif
239 
240 #include <linux/dynamic_debug.h>
241 
242 /* If you are writing a driver, please use dev_dbg instead */
243 #if defined(CONFIG_DYNAMIC_DEBUG)
244 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
245 #define pr_debug(fmt, ...) \
246 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
247 #elif defined(DEBUG)
248 #define pr_debug(fmt, ...) \
249 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
250 #else
251 #define pr_debug(fmt, ...) \
252 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
253 #endif
254 
255 /*
256  * Print a one-time message (analogous to WARN_ONCE() et al):
257  */
258 
259 #ifdef CONFIG_PRINTK
260 #define printk_once(fmt, ...)					\
261 ({								\
262 	static bool __print_once __read_mostly;			\
263 								\
264 	if (!__print_once) {					\
265 		__print_once = true;				\
266 		printk(fmt, ##__VA_ARGS__);			\
267 	}							\
268 })
269 #else
270 #define printk_once(fmt, ...)					\
271 	no_printk(fmt, ##__VA_ARGS__)
272 #endif
273 
274 #define pr_emerg_once(fmt, ...)					\
275 	printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
276 #define pr_alert_once(fmt, ...)					\
277 	printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
278 #define pr_crit_once(fmt, ...)					\
279 	printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
280 #define pr_err_once(fmt, ...)					\
281 	printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
282 #define pr_warn_once(fmt, ...)					\
283 	printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
284 #define pr_notice_once(fmt, ...)				\
285 	printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
286 #define pr_info_once(fmt, ...)					\
287 	printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
288 #define pr_cont_once(fmt, ...)					\
289 	printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
290 
291 #if defined(DEBUG)
292 #define pr_devel_once(fmt, ...)					\
293 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
294 #else
295 #define pr_devel_once(fmt, ...)					\
296 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
297 #endif
298 
299 /* If you are writing a driver, please use dev_dbg instead */
300 #if defined(DEBUG)
301 #define pr_debug_once(fmt, ...)					\
302 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
303 #else
304 #define pr_debug_once(fmt, ...)					\
305 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
306 #endif
307 
308 /*
309  * ratelimited messages with local ratelimit_state,
310  * no local ratelimit_state used in the !PRINTK case
311  */
312 #ifdef CONFIG_PRINTK
313 #define printk_ratelimited(fmt, ...)					\
314 ({									\
315 	static DEFINE_RATELIMIT_STATE(_rs,				\
316 				      DEFAULT_RATELIMIT_INTERVAL,	\
317 				      DEFAULT_RATELIMIT_BURST);		\
318 									\
319 	if (__ratelimit(&_rs))						\
320 		printk(fmt, ##__VA_ARGS__);				\
321 })
322 #else
323 #define printk_ratelimited(fmt, ...)					\
324 	no_printk(fmt, ##__VA_ARGS__)
325 #endif
326 
327 #define pr_emerg_ratelimited(fmt, ...)					\
328 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
329 #define pr_alert_ratelimited(fmt, ...)					\
330 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
331 #define pr_crit_ratelimited(fmt, ...)					\
332 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
333 #define pr_err_ratelimited(fmt, ...)					\
334 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
335 #define pr_warn_ratelimited(fmt, ...)					\
336 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
337 #define pr_notice_ratelimited(fmt, ...)					\
338 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
339 #define pr_info_ratelimited(fmt, ...)					\
340 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
341 /* no pr_cont_ratelimited, don't do that... */
342 
343 #if defined(DEBUG)
344 #define pr_devel_ratelimited(fmt, ...)					\
345 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
346 #else
347 #define pr_devel_ratelimited(fmt, ...)					\
348 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
349 #endif
350 
351 /* If you are writing a driver, please use dev_dbg instead */
352 #if defined(CONFIG_DYNAMIC_DEBUG)
353 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
354 #define pr_debug_ratelimited(fmt, ...)					\
355 do {									\
356 	static DEFINE_RATELIMIT_STATE(_rs,				\
357 				      DEFAULT_RATELIMIT_INTERVAL,	\
358 				      DEFAULT_RATELIMIT_BURST);		\
359 	DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt);			\
360 	if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&	\
361 	    __ratelimit(&_rs))						\
362 		__dynamic_pr_debug(&descriptor, fmt, ##__VA_ARGS__);	\
363 } while (0)
364 #elif defined(DEBUG)
365 #define pr_debug_ratelimited(fmt, ...)					\
366 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
367 #else
368 #define pr_debug_ratelimited(fmt, ...) \
369 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
370 #endif
371 
372 extern const struct file_operations kmsg_fops;
373 
374 enum {
375 	DUMP_PREFIX_NONE,
376 	DUMP_PREFIX_ADDRESS,
377 	DUMP_PREFIX_OFFSET
378 };
379 extern void hex_dump_to_buffer(const void *buf, size_t len,
380 			       int rowsize, int groupsize,
381 			       char *linebuf, size_t linebuflen, bool ascii);
382 #ifdef CONFIG_PRINTK
383 extern void print_hex_dump(const char *level, const char *prefix_str,
384 			   int prefix_type, int rowsize, int groupsize,
385 			   const void *buf, size_t len, bool ascii);
386 #if defined(CONFIG_DYNAMIC_DEBUG)
387 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len)	\
388 	dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
389 #else
390 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
391 				 const void *buf, size_t len);
392 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
393 #else
394 static inline void print_hex_dump(const char *level, const char *prefix_str,
395 				  int prefix_type, int rowsize, int groupsize,
396 				  const void *buf, size_t len, bool ascii)
397 {
398 }
399 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
400 					const void *buf, size_t len)
401 {
402 }
403 
404 #endif
405 
406 #if defined(CONFIG_DYNAMIC_DEBUG)
407 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,	\
408 			     groupsize, buf, len, ascii)	\
409 	dynamic_hex_dump(prefix_str, prefix_type, rowsize,	\
410 			 groupsize, buf, len, ascii)
411 #else
412 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,		\
413 			     groupsize, buf, len, ascii)		\
414 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,	\
415 		       groupsize, buf, len, ascii)
416 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
417 
418 #endif
419