LXR linux/include/linux/printk.h

   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
  11extern const char linux_banner[];
  12extern const char linux_proc_banner[];
  13
  14#define PRINTK_MAX_SINGLE_HEADER_LEN 2
  15
  16static 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
  28static 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
  36static 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
  62extern 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
  69static inline void console_silent(void)
  70{
  71        console_loglevel = CONSOLE_LOGLEVEL_SILENT;
  72}
  73
  74static 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
  82extern char devkmsg_log_str[];
  83struct ctl_table;
  84
  85extern int suppress_printk;
  86
  87struct 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
 142extern asmlinkage __printf(1, 2)
 143void early_printk(const char *fmt, ...);
 144#else
 145static inline __printf(1, 2) __cold
 146void early_printk(const char *s, ...) { }
 147#endif
 148
 149#ifdef CONFIG_PRINTK_NMI
 150extern void printk_nmi_enter(void);
 151extern void printk_nmi_exit(void);
 152extern void printk_nmi_direct_enter(void);
 153extern void printk_nmi_direct_exit(void);
 154#else
 155static inline void printk_nmi_enter(void) { }
 156static inline void printk_nmi_exit(void) { }
 157static inline void printk_nmi_direct_enter(void) { }
 158static inline void printk_nmi_direct_exit(void) { }
 159#endif /* PRINTK_NMI */
 160
 161#ifdef CONFIG_PRINTK
 162asmlinkage __printf(5, 0)
 163int vprintk_emit(int facility, int level,
 164                 const char *dict, size_t dictlen,
 165                 const char *fmt, va_list args);
 166
 167asmlinkage __printf(1, 0)
 168int vprintk(const char *fmt, va_list args);
 169
 170asmlinkage __printf(1, 2) __cold
 171int 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 */
 183extern int __printk_ratelimit(const char *func);
 184#define printk_ratelimit() __printk_ratelimit(__func__)
 185extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 186                                   unsigned int interval_msec);
 187
 188extern int printk_delay_msec;
 189extern int dmesg_restrict;
 190
 191extern int
 192devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, void __user *buf,
 193                          size_t *lenp, loff_t *ppos);
 194
 195extern void wake_up_klogd(void);
 196
 197char *log_buf_addr_get(void);
 198u32 log_buf_len_get(void);
 199void log_buf_vmcoreinfo_setup(void);
 200void __init setup_log_buf(int early);
 201__printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
 202void dump_stack_print_info(const char *log_lvl);
 203void show_regs_print_info(const char *log_lvl);
 204extern asmlinkage void dump_stack(void) __cold;
 205extern void printk_safe_flush(void);
 206extern void printk_safe_flush_on_panic(void);
 207#else
 208static inline __printf(1, 0)
 209int vprintk(const char *s, va_list args)
 210{
 211        return 0;
 212}
 213static inline __printf(1, 2) __cold
 214int printk(const char *s, ...)
 215{
 216        return 0;
 217}
 218static inline __printf(1, 2) __cold
 219int printk_deferred(const char *s, ...)
 220{
 221        return 0;
 222}
 223static inline int printk_ratelimit(void)
 224{
 225        return 0;
 226}
 227static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 228                                          unsigned int interval_msec)
 229{
 230        return false;
 231}
 232
 233static inline void wake_up_klogd(void)
 234{
 235}
 236
 237static inline char *log_buf_addr_get(void)
 238{
 239        return NULL;
 240}
 241
 242static inline u32 log_buf_len_get(void)
 243{
 244        return 0;
 245}
 246
 247static inline void log_buf_vmcoreinfo_setup(void)
 248{
 249}
 250
 251static inline void setup_log_buf(int early)
 252{
 253}
 254
 255static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
 256{
 257}
 258
 259static inline void dump_stack_print_info(const char *log_lvl)
 260{
 261}
 262
 263static inline void show_regs_print_info(const char *log_lvl)
 264{
 265}
 266
 267static inline void dump_stack(void)
 268{
 269}
 270
 271static inline void printk_safe_flush(void)
 272{
 273}
 274
 275static inline void printk_safe_flush_on_panic(void)
 276{
 277}
 278#endif
 279
 280extern 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_warn(fmt, ...) \
 301        printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 302#define pr_notice(fmt, ...) \
 303        printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 304#define pr_info(fmt, ...) \
 305        printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 306/*
 307 * Like KERN_CONT, pr_cont() should only be used when continuing
 308 * a line with no newline ('\n') enclosed. Otherwise it defaults
 309 * back to KERN_DEFAULT.
 310 */
 311#define pr_cont(fmt, ...) \
 312        printk(KERN_CONT fmt, ##__VA_ARGS__)
 313
 314/* pr_devel() should produce zero code unless DEBUG is defined */
 315#ifdef DEBUG
 316#define pr_devel(fmt, ...) \
 317        printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 318#else
 319#define pr_devel(fmt, ...) \
 320        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 321#endif
 322
 323
 324/* If you are writing a driver, please use dev_dbg instead */
 325#if defined(CONFIG_DYNAMIC_DEBUG)
 326#include <linux/dynamic_debug.h>
 327
 328/* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
 329#define pr_debug(fmt, ...) \
 330        dynamic_pr_debug(fmt, ##__VA_ARGS__)
 331#elif defined(DEBUG)
 332#define pr_debug(fmt, ...) \
 333        printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 334#else
 335#define pr_debug(fmt, ...) \
 336        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 337#endif
 338
 339/*
 340 * Print a one-time message (analogous to WARN_ONCE() et al):
 341 */
 342
 343#ifdef CONFIG_PRINTK
 344#define printk_once(fmt, ...)                                   \
 345({                                                              \
 346        static bool __section(.data.once) __print_once;         \
 347        bool __ret_print_once = !__print_once;                  \
 348                                                                \
 349        if (!__print_once) {                                    \
 350                __print_once = true;                            \
 351                printk(fmt, ##__VA_ARGS__);                     \
 352        }                                                       \
 353        unlikely(__ret_print_once);                             \
 354})
 355#define printk_deferred_once(fmt, ...)                          \
 356({                                                              \
 357        static bool __section(.data.once) __print_once;         \
 358        bool __ret_print_once = !__print_once;                  \
 359                                                                \
 360        if (!__print_once) {                                    \
 361                __print_once = true;                            \
 362                printk_deferred(fmt, ##__VA_ARGS__);            \
 363        }                                                       \
 364        unlikely(__ret_print_once);                             \
 365})
 366#else
 367#define printk_once(fmt, ...)                                   \
 368        no_printk(fmt, ##__VA_ARGS__)
 369#define printk_deferred_once(fmt, ...)                          \
 370        no_printk(fmt, ##__VA_ARGS__)
 371#endif
 372
 373#define pr_emerg_once(fmt, ...)                                 \
 374        printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 375#define pr_alert_once(fmt, ...)                                 \
 376        printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 377#define pr_crit_once(fmt, ...)                                  \
 378        printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 379#define pr_err_once(fmt, ...)                                   \
 380        printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 381#define pr_warn_once(fmt, ...)                                  \
 382        printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 383#define pr_notice_once(fmt, ...)                                \
 384        printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 385#define pr_info_once(fmt, ...)                                  \
 386        printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 387#define pr_cont_once(fmt, ...)                                  \
 388        printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
 389
 390#if defined(DEBUG)
 391#define pr_devel_once(fmt, ...)                                 \
 392        printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 393#else
 394#define pr_devel_once(fmt, ...)                                 \
 395        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 396#endif
 397
 398/* If you are writing a driver, please use dev_dbg instead */
 399#if defined(DEBUG)
 400#define pr_debug_once(fmt, ...)                                 \
 401        printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 402#else
 403#define pr_debug_once(fmt, ...)                                 \
 404        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 405#endif
 406
 407/*
 408 * ratelimited messages with local ratelimit_state,
 409 * no local ratelimit_state used in the !PRINTK case
 410 */
 411#ifdef CONFIG_PRINTK
 412#define printk_ratelimited(fmt, ...)                                    \
 413({                                                                      \
 414        static DEFINE_RATELIMIT_STATE(_rs,                              \
 415                                      DEFAULT_RATELIMIT_INTERVAL,       \
 416                                      DEFAULT_RATELIMIT_BURST);         \
 417                                                                        \
 418        if (__ratelimit(&_rs))                                          \
 419                printk(fmt, ##__VA_ARGS__);                             \
 420})
 421#else
 422#define printk_ratelimited(fmt, ...)                                    \
 423        no_printk(fmt, ##__VA_ARGS__)
 424#endif
 425
 426#define pr_emerg_ratelimited(fmt, ...)                                  \
 427        printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
 428#define pr_alert_ratelimited(fmt, ...)                                  \
 429        printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
 430#define pr_crit_ratelimited(fmt, ...)                                   \
 431        printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
 432#define pr_err_ratelimited(fmt, ...)                                    \
 433        printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
 434#define pr_warn_ratelimited(fmt, ...)                                   \
 435        printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
 436#define pr_notice_ratelimited(fmt, ...)                                 \
 437        printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
 438#define pr_info_ratelimited(fmt, ...)                                   \
 439        printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 440/* no pr_cont_ratelimited, don't do that... */
 441
 442#if defined(DEBUG)
 443#define pr_devel_ratelimited(fmt, ...)                                  \
 444        printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 445#else
 446#define pr_devel_ratelimited(fmt, ...)                                  \
 447        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 448#endif
 449
 450/* If you are writing a driver, please use dev_dbg instead */
 451#if defined(CONFIG_DYNAMIC_DEBUG)
 452/* descriptor check is first to prevent flooding with "callbacks suppressed" */
 453#define pr_debug_ratelimited(fmt, ...)                                  \
 454do {                                                                    \
 455        static DEFINE_RATELIMIT_STATE(_rs,                              \
 456                                      DEFAULT_RATELIMIT_INTERVAL,       \
 457                                      DEFAULT_RATELIMIT_BURST);         \
 458        DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt));         \
 459        if (DYNAMIC_DEBUG_BRANCH(descriptor) &&                         \
 460            __ratelimit(&_rs))                                          \
 461                __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__);    \
 462} while (0)
 463#elif defined(DEBUG)
 464#define pr_debug_ratelimited(fmt, ...)                                  \
 465        printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 466#else
 467#define pr_debug_ratelimited(fmt, ...) \
 468        no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
 469#endif
 470
 471extern const struct file_operations kmsg_fops;
 472
 473enum {
 474        DUMP_PREFIX_NONE,
 475        DUMP_PREFIX_ADDRESS,
 476        DUMP_PREFIX_OFFSET
 477};
 478extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize,
 479                              int groupsize, char *linebuf, size_t linebuflen,
 480                              bool ascii);
 481#ifdef CONFIG_PRINTK
 482extern void print_hex_dump(const char *level, const char *prefix_str,
 483                           int prefix_type, int rowsize, int groupsize,
 484                           const void *buf, size_t len, bool ascii);
 485#else
 486static inline 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{
 490}
 491static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 492                                        const void *buf, size_t len)
 493{
 494}
 495
 496#endif
 497
 498#if defined(CONFIG_DYNAMIC_DEBUG)
 499#define print_hex_dump_debug(prefix_str, prefix_type, rowsize,  \
 500                             groupsize, buf, len, ascii)        \
 501        dynamic_hex_dump(prefix_str, prefix_type, rowsize,      \
 502                         groupsize, buf, len, ascii)
 503#elif defined(DEBUG)
 504#define print_hex_dump_debug(prefix_str, prefix_type, rowsize,          \
 505                             groupsize, buf, len, ascii)                \
 506        print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,    \
 507                       groupsize, buf, len, ascii)
 508#else
 509static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
 510                                        int rowsize, int groupsize,
 511                                        const void *buf, size_t len, bool ascii)
 512{
 513}
 514#endif
 515
 516/**
 517 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params
 518 * @prefix_str: string to prefix each line with;
 519 *  caller supplies trailing spaces for alignment if desired
 520 * @prefix_type: controls whether prefix of an offset, address, or none
 521 *  is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE)
 522 * @buf: data blob to dump
 523 * @len: number of bytes in the @buf
 524 *
 525 * Calls print_hex_dump(), with log level of KERN_DEBUG,
 526 * rowsize of 16, groupsize of 1, and ASCII output included.
 527 */
 528#define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
 529        print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true)
 530
 531#endif
 532