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_init(void);
206 extern void printk_safe_flush(void);
207 extern void printk_safe_flush_on_panic(void);
208 #else
209 static inline __printf(1, 0)
vprintk(const char * s,va_list args)210 int vprintk(const char *s, va_list args)
211 {
212 return 0;
213 }
214 static inline __printf(1, 2) __cold
printk(const char * s,...)215 int printk(const char *s, ...)
216 {
217 return 0;
218 }
219 static inline __printf(1, 2) __cold
printk_deferred(const char * s,...)220 int printk_deferred(const char *s, ...)
221 {
222 return 0;
223 }
printk_ratelimit(void)224 static inline int printk_ratelimit(void)
225 {
226 return 0;
227 }
printk_timed_ratelimit(unsigned long * caller_jiffies,unsigned int interval_msec)228 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
229 unsigned int interval_msec)
230 {
231 return false;
232 }
233
wake_up_klogd(void)234 static inline void wake_up_klogd(void)
235 {
236 }
237
log_buf_addr_get(void)238 static inline char *log_buf_addr_get(void)
239 {
240 return NULL;
241 }
242
log_buf_len_get(void)243 static inline u32 log_buf_len_get(void)
244 {
245 return 0;
246 }
247
log_buf_vmcoreinfo_setup(void)248 static inline void log_buf_vmcoreinfo_setup(void)
249 {
250 }
251
setup_log_buf(int early)252 static inline void setup_log_buf(int early)
253 {
254 }
255
dump_stack_set_arch_desc(const char * fmt,...)256 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
257 {
258 }
259
dump_stack_print_info(const char * log_lvl)260 static inline void dump_stack_print_info(const char *log_lvl)
261 {
262 }
263
show_regs_print_info(const char * log_lvl)264 static inline void show_regs_print_info(const char *log_lvl)
265 {
266 }
267
dump_stack(void)268 static inline void dump_stack(void)
269 {
270 }
271
printk_safe_init(void)272 static inline void printk_safe_init(void)
273 {
274 }
275
printk_safe_flush(void)276 static inline void printk_safe_flush(void)
277 {
278 }
279
printk_safe_flush_on_panic(void)280 static inline void printk_safe_flush_on_panic(void)
281 {
282 }
283 #endif
284
285 extern int kptr_restrict;
286
287 #ifndef pr_fmt
288 #define pr_fmt(fmt) fmt
289 #endif
290
291 /*
292 * These can be used to print at the various log levels.
293 * All of these will print unconditionally, although note that pr_debug()
294 * and other debug macros are compiled out unless either DEBUG is defined
295 * or CONFIG_DYNAMIC_DEBUG is set.
296 */
297 #define pr_emerg(fmt, ...) \
298 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
299 #define pr_alert(fmt, ...) \
300 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
301 #define pr_crit(fmt, ...) \
302 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
303 #define pr_err(fmt, ...) \
304 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
305 #define pr_warning(fmt, ...) \
306 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
307 #define pr_warn pr_warning
308 #define pr_notice(fmt, ...) \
309 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
310 #define pr_info(fmt, ...) \
311 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
312 /*
313 * Like KERN_CONT, pr_cont() should only be used when continuing
314 * a line with no newline ('\n') enclosed. Otherwise it defaults
315 * back to KERN_DEFAULT.
316 */
317 #define pr_cont(fmt, ...) \
318 printk(KERN_CONT fmt, ##__VA_ARGS__)
319
320 /* pr_devel() should produce zero code unless DEBUG is defined */
321 #ifdef DEBUG
322 #define pr_devel(fmt, ...) \
323 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
324 #else
325 #define pr_devel(fmt, ...) \
326 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
327 #endif
328
329
330 /* If you are writing a driver, please use dev_dbg instead */
331 #if defined(CONFIG_DYNAMIC_DEBUG)
332 #include <linux/dynamic_debug.h>
333
334 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
335 #define pr_debug(fmt, ...) \
336 dynamic_pr_debug(fmt, ##__VA_ARGS__)
337 #elif defined(DEBUG)
338 #define pr_debug(fmt, ...) \
339 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
340 #else
341 #define pr_debug(fmt, ...) \
342 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
343 #endif
344
345 /*
346 * Print a one-time message (analogous to WARN_ONCE() et al):
347 */
348
349 #ifdef CONFIG_PRINTK
350 #define printk_once(fmt, ...) \
351 ({ \
352 static bool __section(.data.once) __print_once; \
353 bool __ret_print_once = !__print_once; \
354 \
355 if (!__print_once) { \
356 __print_once = true; \
357 printk(fmt, ##__VA_ARGS__); \
358 } \
359 unlikely(__ret_print_once); \
360 })
361 #define printk_deferred_once(fmt, ...) \
362 ({ \
363 static bool __section(.data.once) __print_once; \
364 bool __ret_print_once = !__print_once; \
365 \
366 if (!__print_once) { \
367 __print_once = true; \
368 printk_deferred(fmt, ##__VA_ARGS__); \
369 } \
370 unlikely(__ret_print_once); \
371 })
372 #else
373 #define printk_once(fmt, ...) \
374 no_printk(fmt, ##__VA_ARGS__)
375 #define printk_deferred_once(fmt, ...) \
376 no_printk(fmt, ##__VA_ARGS__)
377 #endif
378
379 #define pr_emerg_once(fmt, ...) \
380 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
381 #define pr_alert_once(fmt, ...) \
382 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
383 #define pr_crit_once(fmt, ...) \
384 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
385 #define pr_err_once(fmt, ...) \
386 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
387 #define pr_warn_once(fmt, ...) \
388 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
389 #define pr_notice_once(fmt, ...) \
390 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
391 #define pr_info_once(fmt, ...) \
392 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
393 #define pr_cont_once(fmt, ...) \
394 printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
395
396 #if defined(DEBUG)
397 #define pr_devel_once(fmt, ...) \
398 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
399 #else
400 #define pr_devel_once(fmt, ...) \
401 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
402 #endif
403
404 /* If you are writing a driver, please use dev_dbg instead */
405 #if defined(DEBUG)
406 #define pr_debug_once(fmt, ...) \
407 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
408 #else
409 #define pr_debug_once(fmt, ...) \
410 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
411 #endif
412
413 /*
414 * ratelimited messages with local ratelimit_state,
415 * no local ratelimit_state used in the !PRINTK case
416 */
417 #ifdef CONFIG_PRINTK
418 #define printk_ratelimited(fmt, ...) \
419 ({ \
420 static DEFINE_RATELIMIT_STATE(_rs, \
421 DEFAULT_RATELIMIT_INTERVAL, \
422 DEFAULT_RATELIMIT_BURST); \
423 \
424 if (__ratelimit(&_rs)) \
425 printk(fmt, ##__VA_ARGS__); \
426 })
427 #else
428 #define printk_ratelimited(fmt, ...) \
429 no_printk(fmt, ##__VA_ARGS__)
430 #endif
431
432 #define pr_emerg_ratelimited(fmt, ...) \
433 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
434 #define pr_alert_ratelimited(fmt, ...) \
435 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
436 #define pr_crit_ratelimited(fmt, ...) \
437 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
438 #define pr_err_ratelimited(fmt, ...) \
439 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
440 #define pr_warn_ratelimited(fmt, ...) \
441 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
442 #define pr_notice_ratelimited(fmt, ...) \
443 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
444 #define pr_info_ratelimited(fmt, ...) \
445 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
446 /* no pr_cont_ratelimited, don't do that... */
447
448 #if defined(DEBUG)
449 #define pr_devel_ratelimited(fmt, ...) \
450 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
451 #else
452 #define pr_devel_ratelimited(fmt, ...) \
453 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
454 #endif
455
456 /* If you are writing a driver, please use dev_dbg instead */
457 #if defined(CONFIG_DYNAMIC_DEBUG)
458 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
459 #define pr_debug_ratelimited(fmt, ...) \
460 do { \
461 static DEFINE_RATELIMIT_STATE(_rs, \
462 DEFAULT_RATELIMIT_INTERVAL, \
463 DEFAULT_RATELIMIT_BURST); \
464 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \
465 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \
466 __ratelimit(&_rs)) \
467 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \
468 } while (0)
469 #elif defined(DEBUG)
470 #define pr_debug_ratelimited(fmt, ...) \
471 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
472 #else
473 #define pr_debug_ratelimited(fmt, ...) \
474 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
475 #endif
476
477 extern const struct file_operations kmsg_fops;
478
479 enum {
480 DUMP_PREFIX_NONE,
481 DUMP_PREFIX_ADDRESS,
482 DUMP_PREFIX_OFFSET
483 };
484 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
485 int groupsize, char *linebuf, size_t linebuflen,
486 bool ascii);
487 #ifdef CONFIG_PRINTK
488 extern void print_hex_dump(const char *level, const char *prefix_str,
489 int prefix_type, int rowsize, int groupsize,
490 const void *buf, size_t len, bool ascii);
491 #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)492 static inline void print_hex_dump(const char *level, const char *prefix_str,
493 int prefix_type, int rowsize, int groupsize,
494 const void *buf, size_t len, bool ascii)
495 {
496 }
print_hex_dump_bytes(const char * prefix_str,int prefix_type,const void * buf,size_t len)497 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
498 const void *buf, size_t len)
499 {
500 }
501
502 #endif
503
504 #if defined(CONFIG_DYNAMIC_DEBUG)
505 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
506 groupsize, buf, len, ascii) \
507 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
508 groupsize, buf, len, ascii)
509 #elif defined(DEBUG)
510 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \
511 groupsize, buf, len, ascii) \
512 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \
513 groupsize, buf, len, ascii)
514 #else
print_hex_dump_debug(const char * prefix_str,int prefix_type,int rowsize,int groupsize,const void * buf,size_t len,bool ascii)515 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
516 int rowsize, int groupsize,
517 const void *buf, size_t len, bool ascii)
518 {
519 }
520 #endif
521
522 /**
523 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
524 * @prefix_str: string to prefix each line with;
525 * caller supplies trailing spaces for alignment if desired
526 * @prefix_type: controls whether prefix of an offset, address, or none
527 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
528 * @buf: data blob to dump
529 * @len: number of bytes in the @buf
530 *
531 * Calls print_hex_dump(), with log level of KERN_DEBUG,
532 * rowsize of 16, groupsize of 1, and ASCII output included.
533 */
534 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
535 print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true)
536
537 #endif
538