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 'd':       /* KERN_DEFAULT */
  22                case 'c':       /* KERN_CONT */
  23                        return buffer[1];
  24                }
  25        }
  26        return 0;
  27}
  28
  29static inline const char *printk_skip_level(const char *buffer)
  30{
  31        if (printk_get_level(buffer))
  32                return buffer + 2;
  33
  34        return buffer;
  35}
  36
  37static inline const char *printk_skip_headers(const char *buffer)
  38{
  39        while (printk_get_level(buffer))
  40                buffer = printk_skip_level(buffer);
  41
  42        return buffer;
  43}
  44
  45#define CONSOLE_EXT_LOG_MAX     8192
  46
  47/* printk's without a loglevel use this.. */
  48#define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT
  49
  50/* We show everything that is MORE important than this.. */
  51#define CONSOLE_LOGLEVEL_SILENT  0 /* Mum's the word */
  52#define CONSOLE_LOGLEVEL_MIN     1 /* Minimum loglevel we let people use */
  53#define CONSOLE_LOGLEVEL_QUIET   4 /* Shhh ..., when booted with "quiet" */
  54#define CONSOLE_LOGLEVEL_DEBUG  10 /* issue debug messages */
  55#define CONSOLE_LOGLEVEL_MOTORMOUTH 15  /* You can't shut this one up */
  56
  57/*
  58 * Default used to be hard-coded at 7, we're now allowing it to be set from
  59 * kernel config.
  60 */
  61#define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT
  62
  63extern int console_printk[];
  64
  65#define console_loglevel (console_printk[0])
  66#define default_message_loglevel (console_printk[1])
  67#define minimum_console_loglevel (console_printk[2])
  68#define default_console_loglevel (console_printk[3])
  69
  70static inline void console_silent(void)
  71{
  72        console_loglevel = CONSOLE_LOGLEVEL_SILENT;
  73}
  74
  75static inline void console_verbose(void)
  76{
  77        if (console_loglevel)
  78                console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH;
  79}
  80
  81/* strlen("ratelimit") + 1 */
  82#define DEVKMSG_STR_MAX_SIZE 10
  83extern char devkmsg_log_str[];
  84struct ctl_table;
  85
  86struct va_format {
  87        const char *fmt;
  88        va_list *va;
  89};
  90
  91/*
  92 * FW_BUG
  93 * Add this to a message where you are sure the firmware is buggy or behaves
  94 * really stupid or out of spec. Be aware that the responsible BIOS developer
  95 * should be able to fix this issue or at least get a concrete idea of the
  96 * problem by reading your message without the need of looking at the kernel
  97 * code.
  98 *
  99 * Use it for definite and high priority BIOS bugs.
 100 *
 101 * FW_WARN
 102 * Use it for not that clear (e.g. could the kernel messed up things already?)
 103 * and medium priority BIOS bugs.
 104 *
 105 * FW_INFO
 106 * Use this one if you want to tell the user or vendor about something
 107 * suspicious, but generally harmless related to the firmware.
 108 *
 109 * Use it for information or very low priority BIOS bugs.
 110 */
 111#define FW_BUG          "[Firmware Bug]: "
 112#define FW_WARN         "[Firmware Warn]: "
 113#define FW_INFO         "[Firmware Info]: "
 114
 115/*
 116 * HW_ERR
 117 * Add this to a message for hardware errors, so that user can report
 118 * it to hardware vendor instead of LKML or software vendor.
 119 */
 120#define HW_ERR          "[Hardware Error]: "
 121
 122/*
 123 * DEPRECATED
 124 * Add this to a message whenever you want to warn user space about the use
 125 * of a deprecated aspect of an API so they can stop using it
 126 */
 127#define DEPRECATED      "[Deprecated]: "
 128
 129/*
 130 * Dummy printk for disabled debugging statements to use whilst maintaining
 131 * gcc's format checking.
 132 */
 133#define no_printk(fmt, ...)                             \
 134({                                                      \
 135        if (0)                                          \
 136                printk(fmt, ##__VA_ARGS__);             \
 137        0;                                              \
 138})
 139
 140#ifdef CONFIG_EARLY_PRINTK
 141extern asmlinkage __printf(1, 2)
 142void early_printk(const char *fmt, ...);
 143#else
 144static inline __printf(1, 2) __cold
 145void early_printk(const char *s, ...) { }
 146#endif
 147
 148#ifdef CONFIG_PRINTK_NMI
 149extern void printk_nmi_enter(void);
 150extern void printk_nmi_exit(void);
 151#else
 152static inline void printk_nmi_enter(void) { }
 153static inline void printk_nmi_exit(void) { }
 154#endif /* PRINTK_NMI */
 155
 156#ifdef CONFIG_PRINTK
 157asmlinkage __printf(5, 0)
 158int vprintk_emit(int facility, int level,
 159                 const char *dict, size_t dictlen,
 160                 const char *fmt, va_list args);
 161
 162asmlinkage __printf(1, 0)
 163int vprintk(const char *fmt, va_list args);
 164
 165asmlinkage __printf(5, 6) __cold
 166int printk_emit(int facility, int level,
 167                const char *dict, size_t dictlen,
 168                const char *fmt, ...);
 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_init(void);
 206extern void printk_safe_flush(void);
 207extern void printk_safe_flush_on_panic(void);
 208#else
 209static inline __printf(1, 0)
 210int vprintk(const char *s, va_list args)
 211{
 212        return 0;
 213}
 214static inline __printf(1, 2) __cold
 215int printk(const char *s, ...)
 216{
 217        return 0;
 218}
 219static inline __printf(1, 2) __cold
 220int printk_deferred(const char *s, ...)
 221{
 222        return 0;
 223}
 224static inline int printk_ratelimit(void)
 225{
 226        return 0;
 227}
 228static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
 229                                          unsigned int interval_msec)
 230{
 231        return false;
 232}
 233
 234static inline void wake_up_klogd(void)
 235{
 236}
 237
 238static inline char *log_buf_addr_get(void)
 239{
 240        return NULL;
 241}
 242
 243static inline u32 log_buf_len_get(void)
 244{
 245        return 0;
 246}
 247
 248static inline void log_buf_vmcoreinfo_setup(void)
 249{
 250}
 251
 252static inline void setup_log_buf(int early)
 253{
 254}
 255
 256static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...)
 257{
 258}
 259
 260static inline void dump_stack_print_info(const char *log_lvl)
 261{
 262}
 263
 264static inline void show_regs_print_info(const char *log_lvl)
 265{
 266}
 267
 268static inline asmlinkage void dump_stack(void)
 269{
 270}
 271
 272static inline void printk_safe_init(void)
 273{
 274}
 275
 276static inline void printk_safe_flush(void)
 277{
 278}
 279
 280static inline void printk_safe_flush_on_panic(void)
 281{
 282}
 283#endif
 284
 285extern 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 __print_once __read_mostly;                 \
 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 __print_once __read_mostly;                 \
 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, ...)                                  \
 460do {                                                                    \
 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 (unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) &&        \
 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
 477extern const struct file_operations kmsg_fops;
 478
 479enum {
 480        DUMP_PREFIX_NONE,
 481        DUMP_PREFIX_ADDRESS,
 482        DUMP_PREFIX_OFFSET
 483};
 484extern 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
 488extern 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#if defined(CONFIG_DYNAMIC_DEBUG)
 492#define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \
 493        dynamic_hex_dump(prefix_str, prefix_type, 16, 1, buf, len, true)
 494#else
 495extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 496                                 const void *buf, size_t len);
 497#endif /* defined(CONFIG_DYNAMIC_DEBUG) */
 498#else
 499static inline void print_hex_dump(const char *level, const char *prefix_str,
 500                                  int prefix_type, int rowsize, int groupsize,
 501                                  const void *buf, size_t len, bool ascii)
 502{
 503}
 504static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 505                                        const void *buf, size_t len)
 506{
 507}
 508
 509#endif
 510
 511#if defined(CONFIG_DYNAMIC_DEBUG)
 512#define print_hex_dump_debug(prefix_str, prefix_type, rowsize,  \
 513                             groupsize, buf, len, ascii)        \
 514        dynamic_hex_dump(prefix_str, prefix_type, rowsize,      \
 515                         groupsize, buf, len, ascii)
 516#elif defined(DEBUG)
 517#define print_hex_dump_debug(prefix_str, prefix_type, rowsize,          \
 518                             groupsize, buf, len, ascii)                \
 519        print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize,    \
 520                       groupsize, buf, len, ascii)
 521#else
 522static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type,
 523                                        int rowsize, int groupsize,
 524                                        const void *buf, size_t len, bool ascii)
 525{
 526}
 527#endif
 528
 529#endif
 530