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 *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 /** 283 * pr_fmt - used by the pr_*() macros to generate the printk format string 284 * @fmt: format string passed from a pr_*() macro 285 * 286 * This macro can be used to generate a unified format string for pr_*() 287 * macros. A common use is to prefix all pr_*() messages in a file with a common 288 * string. For example, defining this at the top of a source file: 289 * 290 * #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 291 * 292 * would prefix all pr_info, pr_emerg... messages in the file with the module 293 * name. 294 */ 295 #ifndef pr_fmt 296 #define pr_fmt(fmt) fmt 297 #endif 298 299 /** 300 * pr_emerg - Print an emergency-level message 301 * @fmt: format string 302 * @...: arguments for the format string 303 * 304 * This macro expands to a printk with KERN_EMERG loglevel. It uses pr_fmt() to 305 * generate the format string. 306 */ 307 #define pr_emerg(fmt, ...) \ 308 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 309 /** 310 * pr_alert - Print an alert-level message 311 * @fmt: format string 312 * @...: arguments for the format string 313 * 314 * This macro expands to a printk with KERN_ALERT loglevel. It uses pr_fmt() to 315 * generate the format string. 316 */ 317 #define pr_alert(fmt, ...) \ 318 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 319 /** 320 * pr_crit - Print a critical-level message 321 * @fmt: format string 322 * @...: arguments for the format string 323 * 324 * This macro expands to a printk with KERN_CRIT loglevel. It uses pr_fmt() to 325 * generate the format string. 326 */ 327 #define pr_crit(fmt, ...) \ 328 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 329 /** 330 * pr_err - Print an error-level message 331 * @fmt: format string 332 * @...: arguments for the format string 333 * 334 * This macro expands to a printk with KERN_ERR loglevel. It uses pr_fmt() to 335 * generate the format string. 336 */ 337 #define pr_err(fmt, ...) \ 338 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 339 /** 340 * pr_warn - Print a warning-level message 341 * @fmt: format string 342 * @...: arguments for the format string 343 * 344 * This macro expands to a printk with KERN_WARNING loglevel. It uses pr_fmt() 345 * to generate the format string. 346 */ 347 #define pr_warn(fmt, ...) \ 348 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 349 /** 350 * pr_notice - Print a notice-level message 351 * @fmt: format string 352 * @...: arguments for the format string 353 * 354 * This macro expands to a printk with KERN_NOTICE loglevel. It uses pr_fmt() to 355 * generate the format string. 356 */ 357 #define pr_notice(fmt, ...) \ 358 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 359 /** 360 * pr_info - Print an info-level message 361 * @fmt: format string 362 * @...: arguments for the format string 363 * 364 * This macro expands to a printk with KERN_INFO loglevel. It uses pr_fmt() to 365 * generate the format string. 366 */ 367 #define pr_info(fmt, ...) \ 368 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 369 370 /** 371 * pr_cont - Continues a previous log message in the same line. 372 * @fmt: format string 373 * @...: arguments for the format string 374 * 375 * This macro expands to a printk with KERN_CONT loglevel. It should only be 376 * used when continuing a log message with no newline ('\n') enclosed. Otherwise 377 * it defaults back to KERN_DEFAULT loglevel. 378 */ 379 #define pr_cont(fmt, ...) \ 380 printk(KERN_CONT fmt, ##__VA_ARGS__) 381 382 /** 383 * pr_devel - Print a debug-level message conditionally 384 * @fmt: format string 385 * @...: arguments for the format string 386 * 387 * This macro expands to a printk with KERN_DEBUG loglevel if DEBUG is 388 * defined. Otherwise it does nothing. 389 * 390 * It uses pr_fmt() to generate the format string. 391 */ 392 #ifdef DEBUG 393 #define pr_devel(fmt, ...) \ 394 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 395 #else 396 #define pr_devel(fmt, ...) \ 397 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 398 #endif 399 400 401 /* If you are writing a driver, please use dev_dbg instead */ 402 #if defined(CONFIG_DYNAMIC_DEBUG) || \ 403 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) 404 #include <linux/dynamic_debug.h> 405 406 /** 407 * pr_debug - Print a debug-level message conditionally 408 * @fmt: format string 409 * @...: arguments for the format string 410 * 411 * This macro expands to dynamic_pr_debug() if CONFIG_DYNAMIC_DEBUG is 412 * set. Otherwise, if DEBUG is defined, it's equivalent to a printk with 413 * KERN_DEBUG loglevel. If DEBUG is not defined it does nothing. 414 * 415 * It uses pr_fmt() to generate the format string (dynamic_pr_debug() uses 416 * pr_fmt() internally). 417 */ 418 #define pr_debug(fmt, ...) \ 419 dynamic_pr_debug(fmt, ##__VA_ARGS__) 420 #elif defined(DEBUG) 421 #define pr_debug(fmt, ...) \ 422 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 423 #else 424 #define pr_debug(fmt, ...) \ 425 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 426 #endif 427 428 /* 429 * Print a one-time message (analogous to WARN_ONCE() et al): 430 */ 431 432 #ifdef CONFIG_PRINTK 433 #define printk_once(fmt, ...) \ 434 ({ \ 435 static bool __section(.data.once) __print_once; \ 436 bool __ret_print_once = !__print_once; \ 437 \ 438 if (!__print_once) { \ 439 __print_once = true; \ 440 printk(fmt, ##__VA_ARGS__); \ 441 } \ 442 unlikely(__ret_print_once); \ 443 }) 444 #define printk_deferred_once(fmt, ...) \ 445 ({ \ 446 static bool __section(.data.once) __print_once; \ 447 bool __ret_print_once = !__print_once; \ 448 \ 449 if (!__print_once) { \ 450 __print_once = true; \ 451 printk_deferred(fmt, ##__VA_ARGS__); \ 452 } \ 453 unlikely(__ret_print_once); \ 454 }) 455 #else 456 #define printk_once(fmt, ...) \ 457 no_printk(fmt, ##__VA_ARGS__) 458 #define printk_deferred_once(fmt, ...) \ 459 no_printk(fmt, ##__VA_ARGS__) 460 #endif 461 462 #define pr_emerg_once(fmt, ...) \ 463 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 464 #define pr_alert_once(fmt, ...) \ 465 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 466 #define pr_crit_once(fmt, ...) \ 467 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 468 #define pr_err_once(fmt, ...) \ 469 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 470 #define pr_warn_once(fmt, ...) \ 471 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 472 #define pr_notice_once(fmt, ...) \ 473 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 474 #define pr_info_once(fmt, ...) \ 475 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 476 /* no pr_cont_once, don't do that... */ 477 478 #if defined(DEBUG) 479 #define pr_devel_once(fmt, ...) \ 480 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 481 #else 482 #define pr_devel_once(fmt, ...) \ 483 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 484 #endif 485 486 /* If you are writing a driver, please use dev_dbg instead */ 487 #if defined(DEBUG) 488 #define pr_debug_once(fmt, ...) \ 489 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 490 #else 491 #define pr_debug_once(fmt, ...) \ 492 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 493 #endif 494 495 /* 496 * ratelimited messages with local ratelimit_state, 497 * no local ratelimit_state used in the !PRINTK case 498 */ 499 #ifdef CONFIG_PRINTK 500 #define printk_ratelimited(fmt, ...) \ 501 ({ \ 502 static DEFINE_RATELIMIT_STATE(_rs, \ 503 DEFAULT_RATELIMIT_INTERVAL, \ 504 DEFAULT_RATELIMIT_BURST); \ 505 \ 506 if (__ratelimit(&_rs)) \ 507 printk(fmt, ##__VA_ARGS__); \ 508 }) 509 #else 510 #define printk_ratelimited(fmt, ...) \ 511 no_printk(fmt, ##__VA_ARGS__) 512 #endif 513 514 #define pr_emerg_ratelimited(fmt, ...) \ 515 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 516 #define pr_alert_ratelimited(fmt, ...) \ 517 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 518 #define pr_crit_ratelimited(fmt, ...) \ 519 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 520 #define pr_err_ratelimited(fmt, ...) \ 521 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 522 #define pr_warn_ratelimited(fmt, ...) \ 523 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 524 #define pr_notice_ratelimited(fmt, ...) \ 525 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 526 #define pr_info_ratelimited(fmt, ...) \ 527 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 528 /* no pr_cont_ratelimited, don't do that... */ 529 530 #if defined(DEBUG) 531 #define pr_devel_ratelimited(fmt, ...) \ 532 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 533 #else 534 #define pr_devel_ratelimited(fmt, ...) \ 535 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 536 #endif 537 538 /* If you are writing a driver, please use dev_dbg instead */ 539 #if defined(CONFIG_DYNAMIC_DEBUG) || \ 540 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) 541 /* descriptor check is first to prevent flooding with "callbacks suppressed" */ 542 #define pr_debug_ratelimited(fmt, ...) \ 543 do { \ 544 static DEFINE_RATELIMIT_STATE(_rs, \ 545 DEFAULT_RATELIMIT_INTERVAL, \ 546 DEFAULT_RATELIMIT_BURST); \ 547 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \ 548 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \ 549 __ratelimit(&_rs)) \ 550 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \ 551 } while (0) 552 #elif defined(DEBUG) 553 #define pr_debug_ratelimited(fmt, ...) \ 554 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 555 #else 556 #define pr_debug_ratelimited(fmt, ...) \ 557 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 558 #endif 559 560 extern const struct file_operations kmsg_fops; 561 562 enum { 563 DUMP_PREFIX_NONE, 564 DUMP_PREFIX_ADDRESS, 565 DUMP_PREFIX_OFFSET 566 }; 567 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, 568 int groupsize, char *linebuf, size_t linebuflen, 569 bool ascii); 570 #ifdef CONFIG_PRINTK 571 extern void print_hex_dump(const char *level, const char *prefix_str, 572 int prefix_type, int rowsize, int groupsize, 573 const void *buf, size_t len, bool ascii); 574 #else 575 static inline void print_hex_dump(const char *level, const char *prefix_str, 576 int prefix_type, int rowsize, int groupsize, 577 const void *buf, size_t len, bool ascii) 578 { 579 } 580 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 581 const void *buf, size_t len) 582 { 583 } 584 585 #endif 586 587 #if defined(CONFIG_DYNAMIC_DEBUG) || \ 588 (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) 589 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \ 590 groupsize, buf, len, ascii) \ 591 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ 592 groupsize, buf, len, ascii) 593 #elif defined(DEBUG) 594 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \ 595 groupsize, buf, len, ascii) \ 596 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \ 597 groupsize, buf, len, ascii) 598 #else 599 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type, 600 int rowsize, int groupsize, 601 const void *buf, size_t len, bool ascii) 602 { 603 } 604 #endif 605 606 /** 607 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params 608 * @prefix_str: string to prefix each line with; 609 * caller supplies trailing spaces for alignment if desired 610 * @prefix_type: controls whether prefix of an offset, address, or none 611 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) 612 * @buf: data blob to dump 613 * @len: number of bytes in the @buf 614 * 615 * Calls print_hex_dump(), with log level of KERN_DEBUG, 616 * rowsize of 16, groupsize of 1, and ASCII output included. 617 */ 618 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \ 619 print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true) 620 621 #endif 622