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 'c': /* KERN_CONT */
22 return buffer[1];
23 }
24 }
25 return 0;
26 }
27
printk_skip_level(const char * buffer)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
printk_skip_headers(const char * buffer)36 static inline const char *printk_skip_headers(const char *buffer)
37 {
38 while (printk_get_level(buffer))
39 buffer = printk_skip_level(buffer);
40
41 return buffer;
42 }
43
44 #define CONSOLE_EXT_LOG_MAX 8192
45
46 /* printk's without a loglevel use this.. */
47 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
48
49 /* We show everything that is MORE important than this.. */
50 #define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */
51 #define CONSOLE_LOGLEVEL_MIN 1 /* Minimum loglevel we let people use */
52 #define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */
53 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */
54
55 /*
56 * Default used to be hard-coded at 7, quiet used to be hardcoded at 4,
57 * we're now allowing both to be set from kernel config.
58 */
59 #define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
60 #define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET
61
62 extern int console_printk[];
63
64 #define console_loglevel (console_printk[0])
65 #define default_message_loglevel (console_printk[1])
66 #define minimum_console_loglevel (console_printk[2])
67 #define default_console_loglevel (console_printk[3])
68
console_silent(void)69 static inline void console_silent(void)
70 {
71 console_loglevel = CONSOLE_LOGLEVEL_SILENT;
72 }
73
console_verbose(void)74 static inline void console_verbose(void)
75 {
76 if (console_loglevel)
77 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
78 }
79
80 /* strlen("ratelimit") + 1 */
81 #define DEVKMSG_STR_MAX_SIZE 10
82 extern char devkmsg_log_str[];
83 struct ctl_table;
84
85 extern int suppress_printk;
86
87 struct va_format {
88 const char *fmt;
89 va_list *va;
90 };
91
92 /*
93 * FW_BUG
94 * Add this to a message where you are sure the firmware is buggy or behaves
95 * really stupid or out of spec. Be aware that the responsible BIOS developer
96 * should be able to fix this issue or at least get a concrete idea of the
97 * problem by reading your message without the need of looking at the kernel
98 * code.
99 *
100 * Use it for definite and high priority BIOS bugs.
101 *
102 * FW_WARN
103 * Use it for not that clear (e.g. could the kernel messed up things already?)
104 * and medium priority BIOS bugs.
105 *
106 * FW_INFO
107 * Use this one if you want to tell the user or vendor about something
108 * suspicious, but generally harmless related to the firmware.
109 *
110 * Use it for information or very low priority BIOS bugs.
111 */
112 #define FW_BUG "[Firmware Bug]: "
113 #define FW_WARN "[Firmware Warn]: "
114 #define FW_INFO "[Firmware Info]: "
115
116 /*
117 * HW_ERR
118 * Add this to a message for hardware errors, so that user can report
119 * it to hardware vendor instead of LKML or software vendor.
120 */
121 #define HW_ERR "[Hardware Error]: "
122
123 /*
124 * DEPRECATED
125 * Add this to a message whenever you want to warn user space about the use
126 * of a deprecated aspect of an API so they can stop using it
127 */
128 #define DEPRECATED "[Deprecated]: "
129
130 /*
131 * Dummy printk for disabled debugging statements to use whilst maintaining
132 * gcc's format checking.
133 */
134 #define no_printk(fmt, ...) \
135 ({ \
136 if (0) \
137 printk(fmt, ##__VA_ARGS__); \
138 0; \
139 })
140
141 #ifdef CONFIG_EARLY_PRINTK
142 extern asmlinkage __printf(1, 2)
143 void early_printk(const char *fmt, ...);
144 #else
145 static inline __printf(1, 2) __cold
early_printk(const char * s,...)146 void early_printk(const char *s, ...) { }
147 #endif
148
149 #ifdef CONFIG_PRINTK_NMI
150 extern void printk_nmi_enter(void);
151 extern void printk_nmi_exit(void);
152 extern void printk_nmi_direct_enter(void);
153 extern void printk_nmi_direct_exit(void);
154 #else
printk_nmi_enter(void)155 static inline void printk_nmi_enter(void) { }
printk_nmi_exit(void)156 static inline void printk_nmi_exit(void) { }
printk_nmi_direct_enter(void)157 static inline void printk_nmi_direct_enter(void) { }
printk_nmi_direct_exit(void)158 static inline void printk_nmi_direct_exit(void) { }
159 #endif /* PRINTK_NMI */
160
161 #ifdef CONFIG_PRINTK
162 asmlinkage __printf(5, 0)
163 int vprintk_emit(int facility, int level,
164 const char *dict, size_t dictlen,
165 const char *fmt, va_list args);
166
167 asmlinkage __printf(1, 0)
168 int vprintk(const char *fmt, va_list args);
169
170 asmlinkage __printf(1, 2) __cold
171 int printk(const char *fmt, ...);
172
173 /*
174 * Special printk facility for scheduler/timekeeping use only, _DO_NOT_USE_ !
175 */
176 __printf(1, 2) __cold int printk_deferred(const char *fmt, ...);
177
178 /*
179 * Please don't use printk_ratelimit(), because it shares ratelimiting state
180 * with all other unrelated printk_ratelimit() callsites. Instead use
181 * printk_ratelimited() or plain old __ratelimit().
182 */
183 extern int __printk_ratelimit(const char *func);
184 #define printk_ratelimit() __printk_ratelimit(__func__)
185 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
186 unsigned int interval_msec);
187
188 extern int printk_delay_msec;
189 extern int dmesg_restrict;
190
191 extern int
192 devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, void __user *buf,
193 size_t *lenp, loff_t *ppos);
194
195 extern void wake_up_klogd(void);
196
197 char *log_buf_addr_get(void);
198 u32 log_buf_len_get(void);
199 void log_buf_vmcoreinfo_setup(void);
200 void __init setup_log_buf(int early);
201 __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
202 void dump_stack_print_info(const char *log_lvl);
203 void show_regs_print_info(const char *log_lvl);
204 extern asmlinkage void dump_stack(void) __cold;
205 extern void printk_safe_flush(void);
206 extern void printk_safe_flush_on_panic(void);
207 #else
208 static inline __printf(1, 0)
vprintk(const char * s,va_list args)209 int vprintk(const char *s, va_list args)
210 {
211 return 0;
212 }
213 static inline __printf(1, 2) __cold
printk(const char * s,...)214 int printk(const char *s, ...)
215 {
216 return 0;
217 }
218 static inline __printf(1, 2) __cold
printk_deferred(const char * s,...)219 int printk_deferred(const char *s, ...)
220 {
221 return 0;
222 }
printk_ratelimit(void)223 static inline int printk_ratelimit(void)
224 {
225 return 0;
226 }
printk_timed_ratelimit(unsigned long * caller_jiffies,unsigned int interval_msec)227 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
228 unsigned int interval_msec)
229 {
230 return false;
231 }
232
wake_up_klogd(void)233 static inline void wake_up_klogd(void)
234 {
235 }
236
log_buf_addr_get(void)237 static inline char *log_buf_addr_get(void)
238 {
239 return NULL;
240 }
241
log_buf_len_get(void)242 static inline u32 log_buf_len_get(void)
243 {
244 return 0;
245 }
246
log_buf_vmcoreinfo_setup(void)247 static inline void log_buf_vmcoreinfo_setup(void)
248 {
249 }
250
setup_log_buf(int early)251 static inline void setup_log_buf(int early)
252 {
253 }
254
dump_stack_set_arch_desc(const char * fmt,...)255 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
256 {
257 }
258
dump_stack_print_info(const char * log_lvl)259 static inline void dump_stack_print_info(const char *log_lvl)
260 {
261 }
262
show_regs_print_info(const char * log_lvl)263 static inline void show_regs_print_info(const char *log_lvl)
264 {
265 }
266
dump_stack(void)267 static inline void dump_stack(void)
268 {
269 }
270
printk_safe_flush(void)271 static inline void printk_safe_flush(void)
272 {
273 }
274
printk_safe_flush_on_panic(void)275 static inline void printk_safe_flush_on_panic(void)
276 {
277 }
278 #endif
279
280 extern int kptr_restrict;
281
282 #ifndef pr_fmt
283 #define pr_fmt(fmt) fmt
284 #endif
285
286 /*
287 * These can be used to print at the various log levels.
288 * All of these will print unconditionally, although note that pr_debug()
289 * and other debug macros are compiled out unless either DEBUG is defined,
290 * CONFIG_DYNAMIC_DEBUG is set, or CONFIG_DYNAMIC_DEBUG_CORE is set when
291 * DYNAMIC_DEBUG_MODULE being defined for any modules.
292 */
293 #define pr_emerg(fmt, ...) \
294 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
295 #define pr_alert(fmt, ...) \
296 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
297 #define pr_crit(fmt, ...) \
298 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
299 #define pr_err(fmt, ...) \
300 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
301 #define pr_warning(fmt, ...) \
302 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
303 #define pr_warn pr_warning
304 #define pr_notice(fmt, ...) \
305 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
306 #define pr_info(fmt, ...) \
307 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
308 /*
309 * Like KERN_CONT, pr_cont() should only be used when continuing
310 * a line with no newline ('\n') enclosed. Otherwise it defaults
311 * back to KERN_DEFAULT.
312 */
313 #define pr_cont(fmt, ...) \
314 printk(KERN_CONT fmt, ##__VA_ARGS__)
315
316 /* pr_devel() should produce zero code unless DEBUG is defined */
317 #ifdef DEBUG
318 #define pr_devel(fmt, ...) \
319 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
320 #else
321 #define pr_devel(fmt, ...) \
322 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
323 #endif
324
325
326 /* If you are writing a driver, please use dev_dbg instead */
327 #if defined(CONFIG_DYNAMIC_DEBUG) || \
328 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
329 #include <linux/dynamic_debug.h>
330
331 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
332 #define pr_debug(fmt, ...) \
333 dynamic_pr_debug(fmt, ##__VA_ARGS__)
334 #elif defined(DEBUG)
335 #define pr_debug(fmt, ...) \
336 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
337 #else
338 #define pr_debug(fmt, ...) \
339 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
340 #endif
341
342 /*
343 * Print a one-time message (analogous to WARN_ONCE() et al):
344 */
345
346 #ifdef CONFIG_PRINTK
347 #define printk_once(fmt, ...) \
348 ({ \
349 static bool __section(.data.once) __print_once; \
350 bool __ret_print_once = !__print_once; \
351 \
352 if (!__print_once) { \
353 __print_once = true; \
354 printk(fmt, ##__VA_ARGS__); \
355 } \
356 unlikely(__ret_print_once); \
357 })
358 #define printk_deferred_once(fmt, ...) \
359 ({ \
360 static bool __section(.data.once) __print_once; \
361 bool __ret_print_once = !__print_once; \
362 \
363 if (!__print_once) { \
364 __print_once = true; \
365 printk_deferred(fmt, ##__VA_ARGS__); \
366 } \
367 unlikely(__ret_print_once); \
368 })
369 #else
370 #define printk_once(fmt, ...) \
371 no_printk(fmt, ##__VA_ARGS__)
372 #define printk_deferred_once(fmt, ...) \
373 no_printk(fmt, ##__VA_ARGS__)
374 #endif
375
376 #define pr_emerg_once(fmt, ...) \
377 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
378 #define pr_alert_once(fmt, ...) \
379 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
380 #define pr_crit_once(fmt, ...) \
381 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
382 #define pr_err_once(fmt, ...) \
383 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
384 #define pr_warn_once(fmt, ...) \
385 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
386 #define pr_notice_once(fmt, ...) \
387 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
388 #define pr_info_once(fmt, ...) \
389 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
390 #define pr_cont_once(fmt, ...) \
391 printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
392
393 #if defined(DEBUG)
394 #define pr_devel_once(fmt, ...) \
395 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
396 #else
397 #define pr_devel_once(fmt, ...) \
398 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
399 #endif
400
401 /* If you are writing a driver, please use dev_dbg instead */
402 #if defined(DEBUG)
403 #define pr_debug_once(fmt, ...) \
404 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
405 #else
406 #define pr_debug_once(fmt, ...) \
407 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
408 #endif
409
410 /*
411 * ratelimited messages with local ratelimit_state,
412 * no local ratelimit_state used in the !PRINTK case
413 */
414 #ifdef CONFIG_PRINTK
415 #define printk_ratelimited(fmt, ...) \
416 ({ \
417 static DEFINE_RATELIMIT_STATE(_rs, \
418 DEFAULT_RATELIMIT_INTERVAL, \
419 DEFAULT_RATELIMIT_BURST); \
420 \
421 if (__ratelimit(&_rs)) \
422 printk(fmt, ##__VA_ARGS__); \
423 })
424 #else
425 #define printk_ratelimited(fmt, ...) \
426 no_printk(fmt, ##__VA_ARGS__)
427 #endif
428
429 #define pr_emerg_ratelimited(fmt, ...) \
430 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
431 #define pr_alert_ratelimited(fmt, ...) \
432 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
433 #define pr_crit_ratelimited(fmt, ...) \
434 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
435 #define pr_err_ratelimited(fmt, ...) \
436 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
437 #define pr_warn_ratelimited(fmt, ...) \
438 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
439 #define pr_notice_ratelimited(fmt, ...) \
440 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
441 #define pr_info_ratelimited(fmt, ...) \
442 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
443 /* no pr_cont_ratelimited, don't do that... */
444
445 #if defined(DEBUG)
446 #define pr_devel_ratelimited(fmt, ...) \
447 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
448 #else
449 #define pr_devel_ratelimited(fmt, ...) \
450 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
451 #endif
452
453 /* If you are writing a driver, please use dev_dbg instead */
454 #if defined(CONFIG_DYNAMIC_DEBUG) || \
455 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
456 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
457 #define pr_debug_ratelimited(fmt, ...) \
458 do { \
459 static DEFINE_RATELIMIT_STATE(_rs, \
460 DEFAULT_RATELIMIT_INTERVAL, \
461 DEFAULT_RATELIMIT_BURST); \
462 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \
463 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \
464 __ratelimit(&_rs)) \
465 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
466 } while (0)
467 #elif defined(DEBUG)
468 #define pr_debug_ratelimited(fmt, ...) \
469 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
470 #else
471 #define pr_debug_ratelimited(fmt, ...) \
472 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
473 #endif
474
475 extern const struct file_operations kmsg_fops;
476
477 enum {
478 DUMP_PREFIX_NONE,
479 DUMP_PREFIX_ADDRESS,
480 DUMP_PREFIX_OFFSET
481 };
482 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
483 int groupsize, char *linebuf, size_t linebuflen,
484 bool ascii);
485 #ifdef CONFIG_PRINTK
486 extern void print_hex_dump(const char *level, const char *prefix_str,
487 int prefix_type, int rowsize, int groupsize,
488 const void *buf, size_t len, bool ascii);
489 #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)490 static inline void print_hex_dump(const char *level, const char *prefix_str,
491 int prefix_type, int rowsize, int groupsize,
492 const void *buf, size_t len, bool ascii)
493 {
494 }
print_hex_dump_bytes(const char * prefix_str,int prefix_type,const void * buf,size_t len)495 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
496 const void *buf, size_t len)
497 {
498 }
499
500 #endif
501
502 #if defined(CONFIG_DYNAMIC_DEBUG) || \
503 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))
504 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
505 groupsize, buf, len, ascii) \
506 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
507 groupsize, buf, len, ascii)
508 #elif defined(DEBUG)
509 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
510 groupsize, buf, len, ascii) \
511 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \
512 groupsize, buf, len, ascii)
513 #else
print_hex_dump_debug(const char * prefix_str,int prefix_type,int rowsize,int groupsize,const void * buf,size_t len,bool ascii)514 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
515 int rowsize, int groupsize,
516 const void *buf, size_t len, bool ascii)
517 {
518 }
519 #endif
520
521 /**
522 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
523 * @prefix_str: string to prefix each line with;
524 * caller supplies trailing spaces for alignment if desired
525 * @prefix_type: controls whether prefix of an offset, address, or none
526 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
527 * @buf: data blob to dump
528 * @len: number of bytes in the @buf
529 *
530 * Calls print_hex_dump(), with log level of KERN_DEBUG,
531 * rowsize of 16, groupsize of 1, and ASCII output included.
532 */
533 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
534 print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true)
535
536 #ifdef CONFIG_PRINTK
537 extern void __printk_safe_enter(void);
538 extern void __printk_safe_exit(void);
539 /*
540 * The printk_deferred_enter/exit macros are available only as a hack for
541 * some code paths that need to defer all printk console printing. Interrupts
542 * must be disabled for the deferred duration.
543 */
544 #define printk_deferred_enter __printk_safe_enter
545 #define printk_deferred_exit __printk_safe_exit
546 #else
printk_deferred_enter(void)547 static inline void printk_deferred_enter(void)
548 {
549 }
printk_deferred_exit(void)550 static inline void printk_deferred_exit(void)
551 {
552 }
553 #endif
554
555 #endif
556