xref: /openbmc/linux/kernel/printk/internal.h (revision c4e78957)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * internal.h - printk internal definitions
4  */
5 #include <linux/percpu.h>
6 
7 #if defined(CONFIG_PRINTK) && defined(CONFIG_SYSCTL)
8 void __init printk_sysctl_init(void);
9 int devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write,
10 			      void *buffer, size_t *lenp, loff_t *ppos);
11 #else
12 #define printk_sysctl_init() do { } while (0)
13 #endif
14 
15 #ifdef CONFIG_PRINTK
16 
17 /* Flags for a single printk record. */
18 enum printk_info_flags {
19 	LOG_NEWLINE	= 2,	/* text ended with a newline */
20 	LOG_CONT	= 8,	/* text is a fragment of a continuation line */
21 };
22 
23 extern bool block_console_kthreads;
24 
25 __printf(4, 0)
26 int vprintk_store(int facility, int level,
27 		  const struct dev_printk_info *dev_info,
28 		  const char *fmt, va_list args);
29 
30 __printf(1, 0) int vprintk_default(const char *fmt, va_list args);
31 __printf(1, 0) int vprintk_deferred(const char *fmt, va_list args);
32 
33 bool printk_percpu_data_ready(void);
34 
35 #define printk_safe_enter_irqsave(flags)	\
36 	do {					\
37 		local_irq_save(flags);		\
38 		__printk_safe_enter();		\
39 	} while (0)
40 
41 #define printk_safe_exit_irqrestore(flags)	\
42 	do {					\
43 		__printk_safe_exit();		\
44 		local_irq_restore(flags);	\
45 	} while (0)
46 
47 void defer_console_output(void);
48 
49 u16 printk_parse_prefix(const char *text, int *level,
50 			enum printk_info_flags *flags);
51 #else
52 
53 /*
54  * In !PRINTK builds we still export console_sem
55  * semaphore and some of console functions (console_unlock()/etc.), so
56  * printk-safe must preserve the existing local IRQ guarantees.
57  */
58 #define printk_safe_enter_irqsave(flags) local_irq_save(flags)
59 #define printk_safe_exit_irqrestore(flags) local_irq_restore(flags)
60 
61 static inline bool printk_percpu_data_ready(void) { return false; }
62 #endif /* CONFIG_PRINTK */
63