xref: /linux-6.15/include/linux/printk.h (revision 6ed7ffdd)
1 #ifndef __KERNEL_PRINTK__
2 #define __KERNEL_PRINTK__
3 
4 #include <linux/init.h>
5 #include <linux/kern_levels.h>
6 
7 extern const char linux_banner[];
8 extern const char linux_proc_banner[];
9 
10 static inline int printk_get_level(const char *buffer)
11 {
12 	if (buffer[0] == KERN_SOH_ASCII && buffer[1]) {
13 		switch (buffer[1]) {
14 		case '0' ... '7':
15 		case 'd':	/* KERN_DEFAULT */
16 			return buffer[1];
17 		}
18 	}
19 	return 0;
20 }
21 
22 static inline const char *printk_skip_level(const char *buffer)
23 {
24 	if (printk_get_level(buffer)) {
25 		switch (buffer[1]) {
26 		case '0' ... '7':
27 		case 'd':	/* KERN_DEFAULT */
28 			return buffer + 2;
29 		}
30 	}
31 	return buffer;
32 }
33 
34 extern int console_printk[];
35 
36 #define console_loglevel (console_printk[0])
37 #define default_message_loglevel (console_printk[1])
38 #define minimum_console_loglevel (console_printk[2])
39 #define default_console_loglevel (console_printk[3])
40 
41 static inline void console_silent(void)
42 {
43 	console_loglevel = 0;
44 }
45 
46 static inline void console_verbose(void)
47 {
48 	if (console_loglevel)
49 		console_loglevel = 15;
50 }
51 
52 struct va_format {
53 	const char *fmt;
54 	va_list *va;
55 };
56 
57 /*
58  * FW_BUG
59  * Add this to a message where you are sure the firmware is buggy or behaves
60  * really stupid or out of spec. Be aware that the responsible BIOS developer
61  * should be able to fix this issue or at least get a concrete idea of the
62  * problem by reading your message without the need of looking at the kernel
63  * code.
64  *
65  * Use it for definite and high priority BIOS bugs.
66  *
67  * FW_WARN
68  * Use it for not that clear (e.g. could the kernel messed up things already?)
69  * and medium priority BIOS bugs.
70  *
71  * FW_INFO
72  * Use this one if you want to tell the user or vendor about something
73  * suspicious, but generally harmless related to the firmware.
74  *
75  * Use it for information or very low priority BIOS bugs.
76  */
77 #define FW_BUG		"[Firmware Bug]: "
78 #define FW_WARN		"[Firmware Warn]: "
79 #define FW_INFO		"[Firmware Info]: "
80 
81 /*
82  * HW_ERR
83  * Add this to a message for hardware errors, so that user can report
84  * it to hardware vendor instead of LKML or software vendor.
85  */
86 #define HW_ERR		"[Hardware Error]: "
87 
88 /*
89  * Dummy printk for disabled debugging statements to use whilst maintaining
90  * gcc's format and side-effect checking.
91  */
92 static inline __printf(1, 2)
93 int no_printk(const char *fmt, ...)
94 {
95 	return 0;
96 }
97 
98 extern asmlinkage __printf(1, 2)
99 void early_printk(const char *fmt, ...);
100 
101 #ifdef CONFIG_PRINTK
102 asmlinkage __printf(5, 0)
103 int vprintk_emit(int facility, int level,
104 		 const char *dict, size_t dictlen,
105 		 const char *fmt, va_list args);
106 
107 asmlinkage __printf(1, 0)
108 int vprintk(const char *fmt, va_list args);
109 
110 asmlinkage __printf(5, 6) __cold
111 asmlinkage int printk_emit(int facility, int level,
112 			   const char *dict, size_t dictlen,
113 			   const char *fmt, ...);
114 
115 asmlinkage __printf(1, 2) __cold
116 int printk(const char *fmt, ...);
117 
118 /*
119  * Special printk facility for scheduler use only, _DO_NOT_USE_ !
120  */
121 __printf(1, 2) __cold int printk_sched(const char *fmt, ...);
122 
123 /*
124  * Please don't use printk_ratelimit(), because it shares ratelimiting state
125  * with all other unrelated printk_ratelimit() callsites.  Instead use
126  * printk_ratelimited() or plain old __ratelimit().
127  */
128 extern int __printk_ratelimit(const char *func);
129 #define printk_ratelimit() __printk_ratelimit(__func__)
130 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
131 				   unsigned int interval_msec);
132 
133 extern int printk_delay_msec;
134 extern int dmesg_restrict;
135 extern int kptr_restrict;
136 
137 void log_buf_kexec_setup(void);
138 void __init setup_log_buf(int early);
139 #else
140 static inline __printf(1, 0)
141 int vprintk(const char *s, va_list args)
142 {
143 	return 0;
144 }
145 static inline __printf(1, 2) __cold
146 int printk(const char *s, ...)
147 {
148 	return 0;
149 }
150 static inline __printf(1, 2) __cold
151 int printk_sched(const char *s, ...)
152 {
153 	return 0;
154 }
155 static inline int printk_ratelimit(void)
156 {
157 	return 0;
158 }
159 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
160 					  unsigned int interval_msec)
161 {
162 	return false;
163 }
164 
165 static inline void log_buf_kexec_setup(void)
166 {
167 }
168 
169 static inline void setup_log_buf(int early)
170 {
171 }
172 #endif
173 
174 extern void dump_stack(void) __cold;
175 
176 #ifndef pr_fmt
177 #define pr_fmt(fmt) fmt
178 #endif
179 
180 #define pr_emerg(fmt, ...) \
181 	printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
182 #define pr_alert(fmt, ...) \
183 	printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
184 #define pr_crit(fmt, ...) \
185 	printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
186 #define pr_err(fmt, ...) \
187 	printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
188 #define pr_warning(fmt, ...) \
189 	printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
190 #define pr_warn pr_warning
191 #define pr_notice(fmt, ...) \
192 	printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
193 #define pr_info(fmt, ...) \
194 	printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
195 #define pr_cont(fmt, ...) \
196 	printk(KERN_CONT fmt, ##__VA_ARGS__)
197 
198 /* pr_devel() should produce zero code unless DEBUG is defined */
199 #ifdef DEBUG
200 #define pr_devel(fmt, ...) \
201 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
202 #else
203 #define pr_devel(fmt, ...) \
204 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
205 #endif
206 
207 /* If you are writing a driver, please use dev_dbg instead */
208 #if defined(CONFIG_DYNAMIC_DEBUG)
209 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
210 #define pr_debug(fmt, ...) \
211 	dynamic_pr_debug(fmt, ##__VA_ARGS__)
212 #elif defined(DEBUG)
213 #define pr_debug(fmt, ...) \
214 	printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
215 #else
216 #define pr_debug(fmt, ...) \
217 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
218 #endif
219 
220 /*
221  * Print a one-time message (analogous to WARN_ONCE() et al):
222  */
223 
224 #ifdef CONFIG_PRINTK
225 #define printk_once(fmt, ...)			\
226 ({						\
227 	static bool __print_once;		\
228 						\
229 	if (!__print_once) {			\
230 		__print_once = true;		\
231 		printk(fmt, ##__VA_ARGS__);	\
232 	}					\
233 })
234 #else
235 #define printk_once(fmt, ...)			\
236 	no_printk(fmt, ##__VA_ARGS__)
237 #endif
238 
239 #define pr_emerg_once(fmt, ...)					\
240 	printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
241 #define pr_alert_once(fmt, ...)					\
242 	printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
243 #define pr_crit_once(fmt, ...)					\
244 	printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
245 #define pr_err_once(fmt, ...)					\
246 	printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
247 #define pr_warn_once(fmt, ...)					\
248 	printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
249 #define pr_notice_once(fmt, ...)				\
250 	printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
251 #define pr_info_once(fmt, ...)					\
252 	printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
253 #define pr_cont_once(fmt, ...)					\
254 	printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
255 
256 #if defined(DEBUG)
257 #define pr_devel_once(fmt, ...)					\
258 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
259 #else
260 #define pr_devel_once(fmt, ...)					\
261 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
262 #endif
263 
264 /* If you are writing a driver, please use dev_dbg instead */
265 #if defined(DEBUG)
266 #define pr_debug_once(fmt, ...)					\
267 	printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
268 #else
269 #define pr_debug_once(fmt, ...)					\
270 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
271 #endif
272 
273 /*
274  * ratelimited messages with local ratelimit_state,
275  * no local ratelimit_state used in the !PRINTK case
276  */
277 #ifdef CONFIG_PRINTK
278 #define printk_ratelimited(fmt, ...)					\
279 ({									\
280 	static DEFINE_RATELIMIT_STATE(_rs,				\
281 				      DEFAULT_RATELIMIT_INTERVAL,	\
282 				      DEFAULT_RATELIMIT_BURST);		\
283 									\
284 	if (__ratelimit(&_rs))						\
285 		printk(fmt, ##__VA_ARGS__);				\
286 })
287 #else
288 #define printk_ratelimited(fmt, ...)					\
289 	no_printk(fmt, ##__VA_ARGS__)
290 #endif
291 
292 #define pr_emerg_ratelimited(fmt, ...)					\
293 	printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
294 #define pr_alert_ratelimited(fmt, ...)					\
295 	printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
296 #define pr_crit_ratelimited(fmt, ...)					\
297 	printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
298 #define pr_err_ratelimited(fmt, ...)					\
299 	printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
300 #define pr_warn_ratelimited(fmt, ...)					\
301 	printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
302 #define pr_notice_ratelimited(fmt, ...)					\
303 	printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
304 #define pr_info_ratelimited(fmt, ...)					\
305 	printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
306 /* no pr_cont_ratelimited, don't do that... */
307 
308 #if defined(DEBUG)
309 #define pr_devel_ratelimited(fmt, ...)					\
310 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
311 #else
312 #define pr_devel_ratelimited(fmt, ...)					\
313 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
314 #endif
315 
316 /* If you are writing a driver, please use dev_dbg instead */
317 #if defined(DEBUG)
318 #define pr_debug_ratelimited(fmt, ...)					\
319 	printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
320 #else
321 #define pr_debug_ratelimited(fmt, ...) \
322 	no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
323 #endif
324 
325 extern const struct file_operations kmsg_fops;
326 
327 enum {
328 	DUMP_PREFIX_NONE,
329 	DUMP_PREFIX_ADDRESS,
330 	DUMP_PREFIX_OFFSET
331 };
332 extern void hex_dump_to_buffer(const void *buf, size_t len,
333 			       int rowsize, int groupsize,
334 			       char *linebuf, size_t linebuflen, bool ascii);
335 #ifdef CONFIG_PRINTK
336 extern void print_hex_dump(const char *level, const char *prefix_str,
337 			   int prefix_type, int rowsize, int groupsize,
338 			   const void *buf, size_t len, bool ascii);
339 #if defined(CONFIG_DYNAMIC_DEBUG)
340 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len)	\
341 	dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
342 #else
343 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
344 				 const void *buf, size_t len);
345 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
346 #else
347 static inline void print_hex_dump(const char *level, const char *prefix_str,
348 				  int prefix_type, int rowsize, int groupsize,
349 				  const void *buf, size_t len, bool ascii)
350 {
351 }
352 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
353 					const void *buf, size_t len)
354 {
355 }
356 
357 #endif
358 
359 #if defined(CONFIG_DYNAMIC_DEBUG)
360 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,	\
361 			     groupsize, buf, len, ascii)	\
362 	dynamic_hex_dump(prefix_str, prefix_type, rowsize,	\
363 			 groupsize, buf, len, ascii)
364 #else
365 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,		\
366 			     groupsize, buf, len, ascii)		\
367 	print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,	\
368 		       groupsize, buf, len, ascii)
369 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
370 
371 #endif
372