1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __KERNEL_PRINTK__
3 #define __KERNEL_PRINTK__
4
5 #include <stdarg.h>
6 #include <linux/init.h>
7 #include <linux/kern_levels.h>
8 #include <linux/linkage.h>
9 #include <linux/cache.h>
10
11 extern const char linux_banner[];
12 extern const char linux_proc_banner[];
13
14 #define PRINTK_MAX_SINGLE_HEADER_LEN 2
15
printk_get_level(const char * buffer)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 case 'c': /* KERN_CONT */
23 return buffer[1];
24 }
25 }
26 return 0;
27 }
28
printk_skip_level(const char * buffer)29 static inline const char *printk_skip_level(const char *buffer)
30 {
31 if (printk_get_level(buffer))
32 return buffer + 2;
33
34 return buffer;
35 }
36
printk_skip_headers(const char * buffer)37 static inline const char *printk_skip_headers(const char *buffer)
38 {
39 while (printk_get_level(buffer))
40 buffer = printk_skip_level(buffer);
41
42 return buffer;
43 }
44
45 #define CONSOLE_EXT_LOG_MAX 8192
46
47 /* printk's without a loglevel use this.. */
48 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
49
50 /* We show everything that is MORE important than this.. */
51 #define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */
52 #define CONSOLE_LOGLEVEL_MIN 1 /* Minimum loglevel we let people use */
53 #define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */
54 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */
55
56 /*
57 * Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
58 * we're now allowing both to be set from kernel config.
59 */
60 #define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
61 #define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET
62
63 extern int console_printk[];
64
65 #define console_loglevel (console_printk[0])
66 #define default_message_loglevel (console_printk[1])
67 #define minimum_console_loglevel (console_printk[2])
68 #define default_console_loglevel (console_printk[3])
69
console_silent(void)70 static inline void console_silent(void)
71 {
72 console_loglevel = CONSOLE_LOGLEVEL_SILENT;
73 }
74
console_verbose(void)75 static inline void console_verbose(void)
76 {
77 if (console_loglevel)
78 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
79 }
80
81 /* strlen("ratelimit") + 1 */
82 #define DEVKMSG_STR_MAX_SIZE 10
83 extern char devkmsg_log_str[];
84 struct ctl_table;
85
86 struct va_format {
87 const char *fmt;
88 va_list *va;
89 };
90
91 /*
92 * FW_BUG
93 * Add this to a message where you are sure the firmware is buggy or behaves
94 * really stupid or out of spec. Be aware that the responsible BIOS developer
95 * should be able to fix this issue or at least get a concrete idea of the
96 * problem by reading your message without the need of looking at the kernel
97 * code.
98 *
99 * Use it for definite and high priority BIOS bugs.
100 *
101 * FW_WARN
102 * Use it for not that clear (e.g. could the kernel messed up things already?)
103 * and medium priority BIOS bugs.
104 *
105 * FW_INFO
106 * Use this one if you want to tell the user or vendor about something
107 * suspicious, but generally harmless related to the firmware.
108 *
109 * Use it for information or very low priority BIOS bugs.
110 */
111 #define FW_BUG "[Firmware Bug]: "
112 #define FW_WARN "[Firmware Warn]: "
113 #define FW_INFO "[Firmware Info]: "
114
115 /*
116 * HW_ERR
117 * Add this to a message for hardware errors, so that user can report
118 * it to hardware vendor instead of LKML or software vendor.
119 */
120 #define HW_ERR "[Hardware Error]: "
121
122 /*
123 * DEPRECATED
124 * Add this to a message whenever you want to warn user space about the use
125 * of a deprecated aspect of an API so they can stop using it
126 */
127 #define DEPRECATED "[Deprecated]: "
128
129 /*
130 * Dummy printk for disabled debugging statements to use whilst maintaining
131 * gcc's format checking.
132 */
133 #define no_printk(fmt, ...) \
134 ({ \
135 if (0) \
136 printk(fmt, ##__VA_ARGS__); \
137 0; \
138 })
139
140 #ifdef CONFIG_EARLY_PRINTK
141 extern asmlinkage __printf(1, 2)
142 void early_printk(const char *fmt, ...);
143 #else
144 static inline __printf(1, 2) __cold
early_printk(const char * s,...)145 void early_printk(const char *s, ...) { }
146 #endif
147
148 #ifdef CONFIG_PRINTK_NMI
149 extern void printk_nmi_enter(void);
150 extern void printk_nmi_exit(void);
151 extern void printk_nmi_direct_enter(void);
152 extern void printk_nmi_direct_exit(void);
153 #else
printk_nmi_enter(void)154 static inline void printk_nmi_enter(void) { }
printk_nmi_exit(void)155 static inline void printk_nmi_exit(void) { }
printk_nmi_direct_enter(void)156 static inline void printk_nmi_direct_enter(void) { }
printk_nmi_direct_exit(void)157 static inline void printk_nmi_direct_exit(void) { }
158 #endif /* PRINTK_NMI */
159
160 #ifdef CONFIG_PRINTK
161 asmlinkage __printf(5, 0)
162 int vprintk_emit(int facility, int level,
163 const char *dict, size_t dictlen,
164 const char *fmt, va_list args);
165
166 asmlinkage __printf(1, 0)
167 int vprintk(const char *fmt, va_list args);
168
169 asmlinkage __printf(5, 6) __cold
170 int printk_emit(int facility, int level,
171 const char *dict, size_t dictlen,
172 const char *fmt, ...);
173
174 asmlinkage __printf(1, 2) __cold
175 int printk(const char *fmt, ...);
176
177 /*
178 * Special printk facility for scheduler/timekeeping use only, _DO_NOT_USE_ !
179 */
180 __printf(1, 2) __cold int printk_deferred(const char *fmt, ...);
181
182 /*
183 * Please don't use printk_ratelimit(), because it shares ratelimiting state
184 * with all other unrelated printk_ratelimit() callsites. Instead use
185 * printk_ratelimited() or plain old __ratelimit().
186 */
187 extern int __printk_ratelimit(const char *func);
188 #define printk_ratelimit() __printk_ratelimit(__func__)
189 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
190 unsigned int interval_msec);
191
192 extern int printk_delay_msec;
193 extern int dmesg_restrict;
194
195 extern int
196 devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, void __user *buf,
197 size_t *lenp, loff_t *ppos);
198
199 extern void wake_up_klogd(void);
200
201 char *log_buf_addr_get(void);
202 u32 log_buf_len_get(void);
203 void log_buf_vmcoreinfo_setup(void);
204 void __init setup_log_buf(int early);
205 __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
206 void dump_stack_print_info(const char *log_lvl);
207 void show_regs_print_info(const char *log_lvl);
208 extern asmlinkage void dump_stack(void) __cold;
209 extern void printk_safe_flush(void);
210 extern void printk_safe_flush_on_panic(void);
211 #else
212 static inline __printf(1, 0)
vprintk(const char * s,va_list args)213 int vprintk(const char *s, va_list args)
214 {
215 return 0;
216 }
217 static inline __printf(1, 2) __cold
printk(const char * s,...)218 int printk(const char *s, ...)
219 {
220 return 0;
221 }
222 static inline __printf(1, 2) __cold
printk_deferred(const char * s,...)223 int printk_deferred(const char *s, ...)
224 {
225 return 0;
226 }
printk_ratelimit(void)227 static inline int printk_ratelimit(void)
228 {
229 return 0;
230 }
printk_timed_ratelimit(unsigned long * caller_jiffies,unsigned int interval_msec)231 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
232 unsigned int interval_msec)
233 {
234 return false;
235 }
236
wake_up_klogd(void)237 static inline void wake_up_klogd(void)
238 {
239 }
240
log_buf_addr_get(void)241 static inline char *log_buf_addr_get(void)
242 {
243 return NULL;
244 }
245
log_buf_len_get(void)246 static inline u32 log_buf_len_get(void)
247 {
248 return 0;
249 }
250
log_buf_vmcoreinfo_setup(void)251 static inline void log_buf_vmcoreinfo_setup(void)
252 {
253 }
254
setup_log_buf(int early)255 static inline void setup_log_buf(int early)
256 {
257 }
258
dump_stack_set_arch_desc(const char * fmt,...)259 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
260 {
261 }
262
dump_stack_print_info(const char * log_lvl)263 static inline void dump_stack_print_info(const char *log_lvl)
264 {
265 }
266
show_regs_print_info(const char * log_lvl)267 static inline void show_regs_print_info(const char *log_lvl)
268 {
269 }
270
dump_stack(void)271 static inline asmlinkage void dump_stack(void)
272 {
273 }
274
printk_safe_flush(void)275 static inline void printk_safe_flush(void)
276 {
277 }
278
printk_safe_flush_on_panic(void)279 static inline void printk_safe_flush_on_panic(void)
280 {
281 }
282 #endif
283
284 extern int kptr_restrict;
285
286 #ifndef pr_fmt
287 #define pr_fmt(fmt) fmt
288 #endif
289
290 /*
291 * These can be used to print at the various log levels.
292 * All of these will print unconditionally, although note that pr_debug()
293 * and other debug macros are compiled out unless either DEBUG is defined
294 * or CONFIG_DYNAMIC_DEBUG is set.
295 */
296 #define pr_emerg(fmt, ...) \
297 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
298 #define pr_alert(fmt, ...) \
299 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
300 #define pr_crit(fmt, ...) \
301 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
302 #define pr_err(fmt, ...) \
303 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
304 #define pr_warning(fmt, ...) \
305 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
306 #define pr_warn pr_warning
307 #define pr_notice(fmt, ...) \
308 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
309 #define pr_info(fmt, ...) \
310 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
311 /*
312 * Like KERN_CONT, pr_cont() should only be used when continuing
313 * a line with no newline ('\n') enclosed. Otherwise it defaults
314 * back to KERN_DEFAULT.
315 */
316 #define pr_cont(fmt, ...) \
317 printk(KERN_CONT fmt, ##__VA_ARGS__)
318
319 /* pr_devel() should produce zero code unless DEBUG is defined */
320 #ifdef DEBUG
321 #define pr_devel(fmt, ...) \
322 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
323 #else
324 #define pr_devel(fmt, ...) \
325 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
326 #endif
327
328
329 /* If you are writing a driver, please use dev_dbg instead */
330 #if defined(CONFIG_DYNAMIC_DEBUG)
331 #include <linux/dynamic_debug.h>
332
333 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
334 #define pr_debug(fmt, ...) \
335 dynamic_pr_debug(fmt, ##__VA_ARGS__)
336 #elif defined(DEBUG)
337 #define pr_debug(fmt, ...) \
338 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
339 #else
340 #define pr_debug(fmt, ...) \
341 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
342 #endif
343
344 /*
345 * Print a one-time message (analogous to WARN_ONCE() et al):
346 */
347
348 #ifdef CONFIG_PRINTK
349 #define printk_once(fmt, ...) \
350 ({ \
351 static bool __print_once __read_mostly; \
352 bool __ret_print_once = !__print_once; \
353 \
354 if (!__print_once) { \
355 __print_once = true; \
356 printk(fmt, ##__VA_ARGS__); \
357 } \
358 unlikely(__ret_print_once); \
359 })
360 #define printk_deferred_once(fmt, ...) \
361 ({ \
362 static bool __print_once __read_mostly; \
363 bool __ret_print_once = !__print_once; \
364 \
365 if (!__print_once) { \
366 __print_once = true; \
367 printk_deferred(fmt, ##__VA_ARGS__); \
368 } \
369 unlikely(__ret_print_once); \
370 })
371 #else
372 #define printk_once(fmt, ...) \
373 no_printk(fmt, ##__VA_ARGS__)
374 #define printk_deferred_once(fmt, ...) \
375 no_printk(fmt, ##__VA_ARGS__)
376 #endif
377
378 #define pr_emerg_once(fmt, ...) \
379 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
380 #define pr_alert_once(fmt, ...) \
381 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
382 #define pr_crit_once(fmt, ...) \
383 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
384 #define pr_err_once(fmt, ...) \
385 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
386 #define pr_warn_once(fmt, ...) \
387 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
388 #define pr_notice_once(fmt, ...) \
389 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
390 #define pr_info_once(fmt, ...) \
391 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
392 #define pr_cont_once(fmt, ...) \
393 printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
394
395 #if defined(DEBUG)
396 #define pr_devel_once(fmt, ...) \
397 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
398 #else
399 #define pr_devel_once(fmt, ...) \
400 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
401 #endif
402
403 /* If you are writing a driver, please use dev_dbg instead */
404 #if defined(DEBUG)
405 #define pr_debug_once(fmt, ...) \
406 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
407 #else
408 #define pr_debug_once(fmt, ...) \
409 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
410 #endif
411
412 /*
413 * ratelimited messages with local ratelimit_state,
414 * no local ratelimit_state used in the !PRINTK case
415 */
416 #ifdef CONFIG_PRINTK
417 #define printk_ratelimited(fmt, ...) \
418 ({ \
419 static DEFINE_RATELIMIT_STATE(_rs, \
420 DEFAULT_RATELIMIT_INTERVAL, \
421 DEFAULT_RATELIMIT_BURST); \
422 \
423 if (__ratelimit(&_rs)) \
424 printk(fmt, ##__VA_ARGS__); \
425 })
426 #else
427 #define printk_ratelimited(fmt, ...) \
428 no_printk(fmt, ##__VA_ARGS__)
429 #endif
430
431 #define pr_emerg_ratelimited(fmt, ...) \
432 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
433 #define pr_alert_ratelimited(fmt, ...) \
434 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
435 #define pr_crit_ratelimited(fmt, ...) \
436 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
437 #define pr_err_ratelimited(fmt, ...) \
438 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
439 #define pr_warn_ratelimited(fmt, ...) \
440 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
441 #define pr_notice_ratelimited(fmt, ...) \
442 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
443 #define pr_info_ratelimited(fmt, ...) \
444 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
445 /* no pr_cont_ratelimited, don't do that... */
446
447 #if defined(DEBUG)
448 #define pr_devel_ratelimited(fmt, ...) \
449 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
450 #else
451 #define pr_devel_ratelimited(fmt, ...) \
452 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
453 #endif
454
455 /* If you are writing a driver, please use dev_dbg instead */
456 #if defined(CONFIG_DYNAMIC_DEBUG)
457 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
458 #define pr_debug_ratelimited(fmt, ...) \
459 do { \
460 static DEFINE_RATELIMIT_STATE(_rs, \
461 DEFAULT_RATELIMIT_INTERVAL, \
462 DEFAULT_RATELIMIT_BURST); \
463 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \
464 if (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) && \
465 __ratelimit(&_rs)) \
466 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
467 } while (0)
468 #elif defined(DEBUG)
469 #define pr_debug_ratelimited(fmt, ...) \
470 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
471 #else
472 #define pr_debug_ratelimited(fmt, ...) \
473 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
474 #endif
475
476 extern const struct file_operations kmsg_fops;
477
478 enum {
479 DUMP_PREFIX_NONE,
480 DUMP_PREFIX_ADDRESS,
481 DUMP_PREFIX_OFFSET
482 };
483 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
484 int groupsize, char *linebuf, size_t linebuflen,
485 bool ascii);
486 #ifdef CONFIG_PRINTK
487 extern void print_hex_dump(const char *level, const char *prefix_str,
488 int prefix_type, int rowsize, int groupsize,
489 const void *buf, size_t len, bool ascii);
490 #if defined(CONFIG_DYNAMIC_DEBUG)
491 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
492 dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
493 #else
494 extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
495 const void *buf, size_t len);
496 #endif /* defined(CONFIG_DYNAMIC_DEBUG) */
497 #else
print_hex_dump(const char * level,const char * prefix_str,int prefix_type,int rowsize,int groupsize,const void * buf,size_t len,bool ascii)498 static inline void print_hex_dump(const char *level, const char *prefix_str,
499 int prefix_type, int rowsize, int groupsize,
500 const void *buf, size_t len, bool ascii)
501 {
502 }
print_hex_dump_bytes(const char * prefix_str,int prefix_type,const void * buf,size_t len)503 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
504 const void *buf, size_t len)
505 {
506 }
507
508 #endif
509
510 #if defined(CONFIG_DYNAMIC_DEBUG)
511 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
512 groupsize, buf, len, ascii) \
513 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
514 groupsize, buf, len, ascii)
515 #elif defined(DEBUG)
516 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
517 groupsize, buf, len, ascii) \
518 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \
519 groupsize, buf, len, ascii)
520 #else
print_hex_dump_debug(const char * prefix_str,int prefix_type,int rowsize,int groupsize,const void * buf,size_t len,bool ascii)521 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
522 int rowsize, int groupsize,
523 const void *buf, size_t len, bool ascii)
524 {
525 }
526 #endif
527
528 #ifdef CONFIG_PRINTK
529 extern void __printk_safe_enter(void);
530 extern void __printk_safe_exit(void);
531 /*
532 * The printk_deferred_enter/exit macros are available only as a hack for
533 * some code paths that need to defer all printk console printing. Interrupts
534 * must be disabled for the deferred duration.
535 */
536 #define printk_deferred_enter __printk_safe_enter
537 #define printk_deferred_exit __printk_safe_exit
538 #else
printk_deferred_enter(void)539 static inline void printk_deferred_enter(void)
540 {
541 }
printk_deferred_exit(void)542 static inline void printk_deferred_exit(void)
543 {
544 }
545 #endif
546
547 #endif
548