kernel-ark/include/linux/printk.h

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#ifndef __KERNEL_PRINTK__
#define __KERNEL_PRINTK__
#include <linux/init.h>
extern const char linux_banner[];
extern const char linux_proc_banner[];
#define KERN_EMERG "<0>" /* system is unusable */
#define KERN_ALERT "<1>" /* action must be taken immediately */
#define KERN_CRIT "<2>" /* critical conditions */
#define KERN_ERR "<3>" /* error conditions */
#define KERN_WARNING "<4>" /* warning conditions */
#define KERN_NOTICE "<5>" /* normal but significant condition */
#define KERN_INFO "<6>" /* informational */
#define KERN_DEBUG "<7>" /* debug-level messages */
/* Use the default kernel loglevel */
#define KERN_DEFAULT "<d>"
/*
* Annotation for a "continued" line of log printout (only done after a
* line that had no enclosing \n). Only to be used by core/arch code
* during early bootup (a continued line is not SMP-safe otherwise).
*/
#define KERN_CONT "<c>"
extern int console_printk[];
#define console_loglevel (console_printk[0])
#define default_message_loglevel (console_printk[1])
#define minimum_console_loglevel (console_printk[2])
#define default_console_loglevel (console_printk[3])
static inline void console_silent(void)
{
console_loglevel = 0;
}
static inline void console_verbose(void)
{
if (console_loglevel)
console_loglevel = 15;
}
struct va_format {
const char *fmt;
va_list *va;
};
/*
* FW_BUG
* Add this to a message where you are sure the firmware is buggy or behaves
* really stupid or out of spec. Be aware that the responsible BIOS developer
* should be able to fix this issue or at least get a concrete idea of the
* problem by reading your message without the need of looking at the kernel
* code.
*
* Use it for definite and high priority BIOS bugs.
*
* FW_WARN
* Use it for not that clear (e.g. could the kernel messed up things already?)
* and medium priority BIOS bugs.
*
* FW_INFO
* Use this one if you want to tell the user or vendor about something
* suspicious, but generally harmless related to the firmware.
*
* Use it for information or very low priority BIOS bugs.
*/
#define FW_BUG "[Firmware Bug]: "
#define FW_WARN "[Firmware Warn]: "
#define FW_INFO "[Firmware Info]: "
/*
* HW_ERR
* Add this to a message for hardware errors, so that user can report
* it to hardware vendor instead of LKML or software vendor.
*/
#define HW_ERR "[Hardware Error]: "
/*
* Dummy printk for disabled debugging statements to use whilst maintaining
* gcc's format and side-effect checking.
*/
static inline __printf(1, 2)
int no_printk(const char *fmt, ...)
{
return 0;
}
extern asmlinkage __printf(1, 2)
void early_printk(const char *fmt, ...);
extern int printk_needs_cpu(int cpu);
extern void printk_tick(void);
#ifdef CONFIG_PRINTK
printk: convert byte-buffer to variable-length record buffer - Record-based stream instead of the traditional byte stream buffer. All records carry a 64 bit timestamp, the syslog facility and priority in the record header. - Records consume almost the same amount, sometimes less memory than the traditional byte stream buffer (if printk_time is enabled). The record header is 16 bytes long, plus some padding bytes at the end if needed. The byte-stream buffer needed 3 chars for the syslog prefix, 15 char for the timestamp and a newline. - Buffer management is based on message sequence numbers. When records need to be discarded, the reading heads move on to the next full record. Unlike the byte-stream buffer, no old logged lines get truncated or partly overwritten by new ones. Sequence numbers also allow consumers of the log stream to get notified if any message in the stream they are about to read gets discarded during the time of reading. - Better buffered IO support for KERN_CONT continuation lines, when printk() is called multiple times for a single line. The use of KERN_CONT is now mandatory to use continuation; a few places in the kernel need trivial fixes here. The buffering could possibly be extended to per-cpu variables to allow better thread-safety for multiple printk() invocations for a single line. - Full-featured syslog facility value support. Different facilities can tag their messages. All userspace-injected messages enforce a facility value > 0 now, to be able to reliably distinguish them from the kernel-generated messages. Independent subsystems like a baseband processor running its own firmware, or a kernel-related userspace process can use their own unique facility values. Multiple independent log streams can co-exist that way in the same buffer. All share the same global sequence number counter to ensure proper ordering (and interleaving) and to allow the consumers of the log to reliably correlate the events from different facilities. Tested-by: William Douglas <william.douglas@intel.com> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-03 00:29:13 +00:00
asmlinkage __printf(5, 0)
int vprintk_emit(int facility, int level,
const char *dict, size_t dictlen,
const char *fmt, va_list args);
asmlinkage __printf(1, 0)
int vprintk(const char *fmt, va_list args);
printk: convert byte-buffer to variable-length record buffer - Record-based stream instead of the traditional byte stream buffer. All records carry a 64 bit timestamp, the syslog facility and priority in the record header. - Records consume almost the same amount, sometimes less memory than the traditional byte stream buffer (if printk_time is enabled). The record header is 16 bytes long, plus some padding bytes at the end if needed. The byte-stream buffer needed 3 chars for the syslog prefix, 15 char for the timestamp and a newline. - Buffer management is based on message sequence numbers. When records need to be discarded, the reading heads move on to the next full record. Unlike the byte-stream buffer, no old logged lines get truncated or partly overwritten by new ones. Sequence numbers also allow consumers of the log stream to get notified if any message in the stream they are about to read gets discarded during the time of reading. - Better buffered IO support for KERN_CONT continuation lines, when printk() is called multiple times for a single line. The use of KERN_CONT is now mandatory to use continuation; a few places in the kernel need trivial fixes here. The buffering could possibly be extended to per-cpu variables to allow better thread-safety for multiple printk() invocations for a single line. - Full-featured syslog facility value support. Different facilities can tag their messages. All userspace-injected messages enforce a facility value > 0 now, to be able to reliably distinguish them from the kernel-generated messages. Independent subsystems like a baseband processor running its own firmware, or a kernel-related userspace process can use their own unique facility values. Multiple independent log streams can co-exist that way in the same buffer. All share the same global sequence number counter to ensure proper ordering (and interleaving) and to allow the consumers of the log to reliably correlate the events from different facilities. Tested-by: William Douglas <william.douglas@intel.com> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-03 00:29:13 +00:00
asmlinkage __printf(5, 6) __cold
asmlinkage int printk_emit(int facility, int level,
const char *dict, size_t dictlen,
const char *fmt, ...);
asmlinkage __printf(1, 2) __cold
int printk(const char *fmt, ...);
/*
* Special printk facility for scheduler use only, _DO_NOT_USE_ !
*/
__printf(1, 2) __cold int printk_sched(const char *fmt, ...);
/*
* Please don't use printk_ratelimit(), because it shares ratelimiting state
* with all other unrelated printk_ratelimit() callsites. Instead use
* printk_ratelimited() or plain old __ratelimit().
*/
extern int __printk_ratelimit(const char *func);
#define printk_ratelimit() __printk_ratelimit(__func__)
extern bool printk_timed_ratelimit(unsigned long *caller_jiffies,
unsigned int interval_msec);
extern int printk_delay_msec;
extern int dmesg_restrict;
kptr_restrict for hiding kernel pointers from unprivileged users Add the %pK printk format specifier and the /proc/sys/kernel/kptr_restrict sysctl. The %pK format specifier is designed to hide exposed kernel pointers, specifically via /proc interfaces. Exposing these pointers provides an easy target for kernel write vulnerabilities, since they reveal the locations of writable structures containing easily triggerable function pointers. The behavior of %pK depends on the kptr_restrict sysctl. If kptr_restrict is set to 0, no deviation from the standard %p behavior occurs. If kptr_restrict is set to 1, the default, if the current user (intended to be a reader via seq_printf(), etc.) does not have CAP_SYSLOG (currently in the LSM tree), kernel pointers using %pK are printed as 0's. If kptr_restrict is set to 2, kernel pointers using %pK are printed as 0's regardless of privileges. Replacing with 0's was chosen over the default "(null)", which cannot be parsed by userland %p, which expects "(nil)". [akpm@linux-foundation.org: check for IRQ context when !kptr_restrict, save an indent level, s/WARN/WARN_ONCE/] [akpm@linux-foundation.org: coding-style fixup] [randy.dunlap@oracle.com: fix kernel/sysctl.c warning] Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: James Morris <jmorris@namei.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Thomas Graf <tgraf@infradead.org> Cc: Eugene Teo <eugeneteo@kernel.org> Cc: Kees Cook <kees.cook@canonical.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David S. Miller <davem@davemloft.net> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Eric Paris <eparis@parisplace.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 00:59:41 +00:00
extern int kptr_restrict;
void log_buf_kexec_setup(void);
void __init setup_log_buf(int early);
#else
static inline __printf(1, 0)
int vprintk(const char *s, va_list args)
{
return 0;
}
static inline __printf(1, 2) __cold
int printk(const char *s, ...)
{
return 0;
}
static inline __printf(1, 2) __cold
int printk_sched(const char *s, ...)
{
return 0;
}
static inline int printk_ratelimit(void)
{
return 0;
}
static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies,
unsigned int interval_msec)
{
return false;
}
static inline void log_buf_kexec_setup(void)
{
}
static inline void setup_log_buf(int early)
{
}
#endif
extern void dump_stack(void) __cold;
#ifndef pr_fmt
#define pr_fmt(fmt) fmt
#endif
#define pr_emerg(fmt, ...) \
printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
#define pr_alert(fmt, ...) \
printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_crit(fmt, ...) \
printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_err(fmt, ...) \
printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
#define pr_warning(fmt, ...) \
printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
#define pr_warn pr_warning
#define pr_notice(fmt, ...) \
printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
#define pr_info(fmt, ...) \
printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
#define pr_cont(fmt, ...) \
printk(KERN_CONT fmt, ##__VA_ARGS__)
/* pr_devel() should produce zero code unless DEBUG is defined */
#ifdef DEBUG
#define pr_devel(fmt, ...) \
printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#else
#define pr_devel(fmt, ...) \
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif
/* If you are writing a driver, please use dev_dbg instead */
#if defined(CONFIG_DYNAMIC_DEBUG)
/* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */
#define pr_debug(fmt, ...) \
dynamic_pr_debug(fmt, ##__VA_ARGS__)
#elif defined(DEBUG)
#define pr_debug(fmt, ...) \
printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#else
#define pr_debug(fmt, ...) \
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif
/*
* Print a one-time message (analogous to WARN_ONCE() et al):
*/
#ifdef CONFIG_PRINTK
#define printk_once(fmt, ...) \
({ \
static bool __print_once; \
\
if (!__print_once) { \
__print_once = true; \
printk(fmt, ##__VA_ARGS__); \
} \
})
#else
#define printk_once(fmt, ...) \
no_printk(fmt, ##__VA_ARGS__)
#endif
#define pr_emerg_once(fmt, ...) \
printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
#define pr_alert_once(fmt, ...) \
printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_crit_once(fmt, ...) \
printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_err_once(fmt, ...) \
printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
#define pr_warn_once(fmt, ...) \
printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
#define pr_notice_once(fmt, ...) \
printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
#define pr_info_once(fmt, ...) \
printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
#define pr_cont_once(fmt, ...) \
printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__)
/* If you are writing a driver, please use dev_dbg instead */
#if defined(DEBUG)
#define pr_debug_once(fmt, ...) \
printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#else
#define pr_debug_once(fmt, ...) \
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif
/*
* ratelimited messages with local ratelimit_state,
* no local ratelimit_state used in the !PRINTK case
*/
#ifdef CONFIG_PRINTK
#define printk_ratelimited(fmt, ...) \
({ \
static DEFINE_RATELIMIT_STATE(_rs, \
DEFAULT_RATELIMIT_INTERVAL, \
DEFAULT_RATELIMIT_BURST); \
\
if (__ratelimit(&_rs)) \
printk(fmt, ##__VA_ARGS__); \
})
#else
#define printk_ratelimited(fmt, ...) \
no_printk(fmt, ##__VA_ARGS__)
#endif
#define pr_emerg_ratelimited(fmt, ...) \
printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__)
#define pr_alert_ratelimited(fmt, ...) \
printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_crit_ratelimited(fmt, ...) \
printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__)
#define pr_err_ratelimited(fmt, ...) \
printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__)
#define pr_warn_ratelimited(fmt, ...) \
printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
#define pr_notice_ratelimited(fmt, ...) \
printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
#define pr_info_ratelimited(fmt, ...) \
printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
/* no pr_cont_ratelimited, don't do that... */
/* If you are writing a driver, please use dev_dbg instead */
#if defined(DEBUG)
#define pr_debug_ratelimited(fmt, ...) \
printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#else
#define pr_debug_ratelimited(fmt, ...) \
no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__)
#endif
kmsg: export printk records to the /dev/kmsg interface Support for multiple concurrent readers of /dev/kmsg, with read(), seek(), poll() support. Output of message sequence numbers, to allow userspace log consumers to reliably reconnect and reconstruct their state at any given time. After open("/dev/kmsg"), read() always returns *all* buffered records. If only future messages should be read, SEEK_END can be used. In case records get overwritten while /dev/kmsg is held open, or records get faster overwritten than they are read, the next read() will return -EPIPE and the current reading position gets updated to the next available record. The passed sequence numbers allow the log consumer to calculate the amount of lost messages. [root@mop ~]# cat /dev/kmsg 5,0,0;Linux version 3.4.0-rc1+ (kay@mop) (gcc version 4.7.0 20120315 ... 6,159,423091;ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff]) 7,160,424069;pci_root PNP0A03:00: host bridge window [io 0x0000-0x0cf7] (ignored) SUBSYSTEM=acpi DEVICE=+acpi:PNP0A03:00 6,339,5140900;NET: Registered protocol family 10 30,340,5690716;udevd[80]: starting version 181 6,341,6081421;FDC 0 is a S82078B 6,345,6154686;microcode: CPU0 sig=0x623, pf=0x0, revision=0x0 7,346,6156968;sr 1:0:0:0: Attached scsi CD-ROM sr0 SUBSYSTEM=scsi DEVICE=+scsi:1:0:0:0 6,347,6289375;microcode: CPU1 sig=0x623, pf=0x0, revision=0x0 Cc: Karel Zak <kzak@redhat.com> Tested-by: William Douglas <william.douglas@intel.com> Signed-off-by: Kay Sievers <kay@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-03 00:29:41 +00:00
extern const struct file_operations kmsg_fops;
enum {
DUMP_PREFIX_NONE,
DUMP_PREFIX_ADDRESS,
DUMP_PREFIX_OFFSET
};
extern void hex_dump_to_buffer(const void *buf, size_t len,
int rowsize, int groupsize,
char *linebuf, size_t linebuflen, bool ascii);
#ifdef CONFIG_PRINTK
extern void 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);
extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
const void *buf, size_t len);
#else
static inline void 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)
{
}
static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
const void *buf, size_t len)
{
}
#endif
#endif