root/include/linux/printk.h

INCLUDED FROM

DEFINITIONS

1. printk_get_level
2. printk_skip_level
3. printk_skip_headers
4. console_silent
5. console_verbose
6. __printf
7. printk_nmi_enter
8. printk_nmi_exit
9. printk_nmi_direct_enter
10. printk_nmi_direct_exit
11. __printf
12. __printf
13. __printf
14. printk_ratelimit
15. printk_timed_ratelimit
16. wake_up_klogd
17. log_buf_addr_get
18. log_buf_len_get
19. log_buf_vmcoreinfo_setup
20. setup_log_buf
21. __printf
22. dump_stack_print_info
23. show_regs_print_info
24. dump_stack
25. printk_safe_flush
26. printk_safe_flush_on_panic
27. print_hex_dump
28. print_hex_dump_bytes
29. print_hex_dump_debug

   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 
  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 
  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 
  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 
  69 static inline void console_silent(void)
  70 {
  71         console_loglevel = CONSOLE_LOGLEVEL_SILENT;
  72 }
  73 
  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
 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
 155 static inline void printk_nmi_enter(void) { }
 156 static inline void printk_nmi_exit(void) { }
 157 static inline void printk_nmi_direct_enter(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)
 209 int vprintk(const char *s, va_list args)
 210 {
 211         return 0;
 212 }
 213 static inline __printf(1, 2) __cold
 214 int printk(const char *s, ...)
 215 {
 216         return 0;
 217 }
 218 static inline __printf(1, 2) __cold
 219 int printk_deferred(const char *s, ...)
 220 {
 221         return 0;
 222 }
 223 static inline int printk_ratelimit(void)
 224 {
 225         return 0;
 226 }
 227 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 228                                           unsigned int interval_msec)
 229 {
 230         return false;
 231 }
 232 
 233 static inline void wake_up_klogd(void)
 234 {
 235 }
 236 
 237 static inline char *log_buf_addr_get(void)
 238 {
 239         return NULL;
 240 }
 241 
 242 static inline u32 log_buf_len_get(void)
 243 {
 244         return 0;
 245 }
 246 
 247 static inline void log_buf_vmcoreinfo_setup(void)
 248 {
 249 }
 250 
 251 static inline void setup_log_buf(int early)
 252 {
 253 }
 254 
 255 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
 256 {
 257 }
 258 
 259 static inline void dump_stack_print_info(const char *log_lvl)
 260 {
 261 }
 262 
 263 static inline void show_regs_print_info(const char *log_lvl)
 264 {
 265 }
 266 
 267 static inline void dump_stack(void)
 268 {
 269 }
 270 
 271 static inline void printk_safe_flush(void)
 272 {
 273 }
 274 
 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  * or CONFIG_DYNAMIC_DEBUG is set.
 291  */
 292 #define pr_emerg(fmt, ...) \
 293         printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 294 #define pr_alert(fmt, ...) \
 295         printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 296 #define pr_crit(fmt, ...) \
 297         printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 298 #define pr_err(fmt, ...) \
 299         printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 300 #define pr_warning(fmt, ...) \
 301         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 302 #define pr_warn pr_warning
 303 #define pr_notice(fmt, ...) \
 304         printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 305 #define pr_info(fmt, ...) \
 306         printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 307 /*
 308  * Like KERN_CONT, pr_cont() should only be used when continuing
 309  * a line with no newline ('\n') enclosed. Otherwise it defaults
 310  * back to KERN_DEFAULT.
 311  */
 312 #define pr_cont(fmt, ...) \
 313         printk(KERN_CONT fmt, ##__VA_ARGS__)
 314 
 315 /* pr_devel() should produce zero code unless DEBUG is defined */
 316 #ifdef DEBUG
 317 #define pr_devel(fmt, ...) \
 318         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 319 #else
 320 #define pr_devel(fmt, ...) \
 321         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 322 #endif
 323 
 324 
 325 /* If you are writing a driver, please use dev_dbg instead */
 326 #if defined(CONFIG_DYNAMIC_DEBUG)
 327 #include <linux/dynamic_debug.h>
 328 
 329 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
 330 #define pr_debug(fmt, ...) \
 331         dynamic_pr_debug(fmt, ##__VA_ARGS__)
 332 #elif defined(DEBUG)
 333 #define pr_debug(fmt, ...) \
 334         printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 335 #else
 336 #define pr_debug(fmt, ...) \
 337         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 338 #endif
 339 
 340 /*
 341  * Print a one-time message (analogous to WARN_ONCE() et al):
 342  */
 343 
 344 #ifdef CONFIG_PRINTK
 345 #define printk_once(fmt, ...)                                   \
 346 ({                                                              \
 347         static bool __section(.data.once) __print_once;         \
 348         bool __ret_print_once = !__print_once;                  \
 349                                                                 \
 350         if (!__print_once) {                                    \
 351                 __print_once = true;                            \
 352                 printk(fmt, ##__VA_ARGS__);                     \
 353         }                                                       \
 354         unlikely(__ret_print_once);                             \
 355 })
 356 #define printk_deferred_once(fmt, ...)                          \
 357 ({                                                              \
 358         static bool __section(.data.once) __print_once;         \
 359         bool __ret_print_once = !__print_once;                  \
 360                                                                 \
 361         if (!__print_once) {                                    \
 362                 __print_once = true;                            \
 363                 printk_deferred(fmt, ##__VA_ARGS__);            \
 364         }                                                       \
 365         unlikely(__ret_print_once);                             \
 366 })
 367 #else
 368 #define printk_once(fmt, ...)                                   \
 369         no_printk(fmt, ##__VA_ARGS__)
 370 #define printk_deferred_once(fmt, ...)                          \
 371         no_printk(fmt, ##__VA_ARGS__)
 372 #endif
 373 
 374 #define pr_emerg_once(fmt, ...)                                 \
 375         printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 376 #define pr_alert_once(fmt, ...)                                 \
 377         printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 378 #define pr_crit_once(fmt, ...)                                  \
 379         printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 380 #define pr_err_once(fmt, ...)                                   \
 381         printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 382 #define pr_warn_once(fmt, ...)                                  \
 383         printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 384 #define pr_notice_once(fmt, ...)                                \
 385         printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 386 #define pr_info_once(fmt, ...)                                  \
 387         printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 388 #define pr_cont_once(fmt, ...)                                  \
 389         printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
 390 
 391 #if defined(DEBUG)
 392 #define pr_devel_once(fmt, ...)                                 \
 393         printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 394 #else
 395 #define pr_devel_once(fmt, ...)                                 \
 396         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 397 #endif
 398 
 399 /* If you are writing a driver, please use dev_dbg instead */
 400 #if defined(DEBUG)
 401 #define pr_debug_once(fmt, ...)                                 \
 402         printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 403 #else
 404 #define pr_debug_once(fmt, ...)                                 \
 405         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 406 #endif
 407 
 408 /*
 409  * ratelimited messages with local ratelimit_state,
 410  * no local ratelimit_state used in the !PRINTK case
 411  */
 412 #ifdef CONFIG_PRINTK
 413 #define printk_ratelimited(fmt, ...)                                    \
 414 ({                                                                      \
 415         static DEFINE_RATELIMIT_STATE(_rs,                              \
 416                                       DEFAULT_RATELIMIT_INTERVAL,       \
 417                                       DEFAULT_RATELIMIT_BURST);         \
 418                                                                         \
 419         if (__ratelimit(&_rs))                                          \
 420                 printk(fmt, ##__VA_ARGS__);                             \
 421 })
 422 #else
 423 #define printk_ratelimited(fmt, ...)                                    \
 424         no_printk(fmt, ##__VA_ARGS__)
 425 #endif
 426 
 427 #define pr_emerg_ratelimited(fmt, ...)                                  \
 428         printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 429 #define pr_alert_ratelimited(fmt, ...)                                  \
 430         printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 431 #define pr_crit_ratelimited(fmt, ...)                                   \
 432         printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 433 #define pr_err_ratelimited(fmt, ...)                                    \
 434         printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 435 #define pr_warn_ratelimited(fmt, ...)                                   \
 436         printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 437 #define pr_notice_ratelimited(fmt, ...)                                 \
 438         printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 439 #define pr_info_ratelimited(fmt, ...)                                   \
 440         printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 441 /* no pr_cont_ratelimited, don't do that... */
 442 
 443 #if defined(DEBUG)
 444 #define pr_devel_ratelimited(fmt, ...)                                  \
 445         printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 446 #else
 447 #define pr_devel_ratelimited(fmt, ...)                                  \
 448         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 449 #endif
 450 
 451 /* If you are writing a driver, please use dev_dbg instead */
 452 #if defined(CONFIG_DYNAMIC_DEBUG)
 453 /* descriptor check is first to prevent flooding with "callbacks suppressed" */
 454 #define pr_debug_ratelimited(fmt, ...)                                  \
 455 do {                                                                    \
 456         static DEFINE_RATELIMIT_STATE(_rs,                              \
 457                                       DEFAULT_RATELIMIT_INTERVAL,       \
 458                                       DEFAULT_RATELIMIT_BURST);         \
 459         DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt));         \
 460         if (DYNAMIC_DEBUG_BRANCH(descriptor) &&                         \
 461             __ratelimit(&_rs))                                          \
 462                 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__);    \
 463 } while (0)
 464 #elif defined(DEBUG)
 465 #define pr_debug_ratelimited(fmt, ...)                                  \
 466         printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 467 #else
 468 #define pr_debug_ratelimited(fmt, ...) \
 469         no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 470 #endif
 471 
 472 extern const struct file_operations kmsg_fops;
 473 
 474 enum {
 475         DUMP_PREFIX_NONE,
 476         DUMP_PREFIX_ADDRESS,
 477         DUMP_PREFIX_OFFSET
 478 };
 479 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
 480                               int groupsize, char *linebuf, size_t linebuflen,
 481                               bool ascii);
 482 #ifdef CONFIG_PRINTK
 483 extern void print_hex_dump(const char *level, const char *prefix_str,
 484                            int prefix_type, int rowsize, int groupsize,
 485                            const void *buf, size_t len, bool ascii);
 486 #else
 487 static inline 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 {
 491 }
 492 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 493                                         const void *buf, size_t len)
 494 {
 495 }
 496 
 497 #endif
 498 
 499 #if defined(CONFIG_DYNAMIC_DEBUG)
 500 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,  \
 501                              groupsize, buf, len, ascii)        \
 502         dynamic_hex_dump(prefix_str, prefix_type, rowsize,      \
 503                          groupsize, buf, len, ascii)
 504 #elif defined(DEBUG)
 505 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize,          \
 506                              groupsize, buf, len, ascii)                \
 507         print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,    \
 508                        groupsize, buf, len, ascii)
 509 #else
 510 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
 511                                         int rowsize, int groupsize,
 512                                         const void *buf, size_t len, bool ascii)
 513 {
 514 }
 515 #endif
 516 
 517 /**
 518  * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
 519  * @prefix_str: string to prefix each line with;
 520  *  caller supplies trailing spaces for alignment if desired
 521  * @prefix_type: controls whether prefix of an offset, address, or none
 522  *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
 523  * @buf: data blob to dump
 524  * @len: number of bytes in the @buf
 525  *
 526  * Calls print_hex_dump(), with log level of KERN_DEBUG,
 527  * rowsize of 16, groupsize of 1, and ASCII output included.
 528  */
 529 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
 530         print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true)
 531 
 532 #endif