xref: /openbmc/linux/kernel/printk/internal.h (revision 8dde5715)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * internal.h - printk internal definitions
4  */
5 #include <linux/percpu.h>
6 
7 #ifdef CONFIG_PRINTK
8 
9 #define PRINTK_SAFE_CONTEXT_MASK	 0x3fffffff
10 #define PRINTK_NMI_DIRECT_CONTEXT_MASK	 0x40000000
11 #define PRINTK_NMI_CONTEXT_MASK		 0x80000000
12 
13 extern raw_spinlock_t logbuf_lock;
14 
15 __printf(5, 0)
16 int vprintk_store(int facility, int level,
17 		  const char *dict, size_t dictlen,
18 		  const char *fmt, va_list args);
19 
20 __printf(1, 0) int vprintk_default(const char *fmt, va_list args);
21 __printf(1, 0) int vprintk_deferred(const char *fmt, va_list args);
22 __printf(1, 0) int vprintk_func(const char *fmt, va_list args);
23 void __printk_safe_enter(void);
24 void __printk_safe_exit(void);
25 
26 #define printk_safe_enter_irqsave(flags)	\
27 	do {					\
28 		local_irq_save(flags);		\
29 		__printk_safe_enter();		\
30 	} while (0)
31 
32 #define printk_safe_exit_irqrestore(flags)	\
33 	do {					\
34 		__printk_safe_exit();		\
35 		local_irq_restore(flags);	\
36 	} while (0)
37 
38 #define printk_safe_enter_irq()		\
39 	do {					\
40 		local_irq_disable();		\
41 		__printk_safe_enter();		\
42 	} while (0)
43 
44 #define printk_safe_exit_irq()			\
45 	do {					\
46 		__printk_safe_exit();		\
47 		local_irq_enable();		\
48 	} while (0)
49 
50 void defer_console_output(void);
51 
52 #else
53 
54 __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; }
55 
56 /*
57  * In !PRINTK builds we still export logbuf_lock spin_lock, console_sem
58  * semaphore and some of console functions (console_unlock()/etc.), so
59  * printk-safe must preserve the existing local IRQ guarantees.
60  */
61 #define printk_safe_enter_irqsave(flags) local_irq_save(flags)
62 #define printk_safe_exit_irqrestore(flags) local_irq_restore(flags)
63 
64 #define printk_safe_enter_irq() local_irq_disable()
65 #define printk_safe_exit_irq() local_irq_enable()
66 
67 #endif /* CONFIG_PRINTK */
68