1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _X86_IRQFLAGS_H_
3#define _X86_IRQFLAGS_H_
4
5#include <asm/processor-flags.h>
6
7#ifndef __ASSEMBLY__
8
9#include <asm/nospec-branch.h>
10
11/* Provide __cpuidle; we can't safely include <linux/cpu.h> */
12#define __cpuidle __section(".cpuidle.text")
13
14/*
15 * Interrupt control:
16 */
17
18/* Declaration required for gcc < 4.9 to prevent -Werror=missing-prototypes */
19extern inline unsigned long native_save_fl(void);
20extern __always_inline unsigned long native_save_fl(void)
21{
22 unsigned long flags;
23
24 /*
25 * "=rm" is safe here, because "pop" adjusts the stack before
26 * it evaluates its effective address -- this is part of the
27 * documented behavior of the "pop" instruction.
28 */
29 asm volatile("# __raw_save_flags\n\t"
30 "pushf ; pop %0"
31 : "=rm" (flags)
32 : /* no input */
33 : "memory");
34
35 return flags;
36}
37
38static __always_inline void native_irq_disable(void)
39{
40 asm volatile("cli": : :"memory");
41}
42
43static __always_inline void native_irq_enable(void)
44{
45 asm volatile("sti": : :"memory");
46}
47
48static inline __cpuidle void native_safe_halt(void)
49{
50 mds_idle_clear_cpu_buffers();
51 asm volatile("sti; hlt": : :"memory");
52}
53
54static inline __cpuidle void native_halt(void)
55{
56 mds_idle_clear_cpu_buffers();
57 asm volatile("hlt": : :"memory");
58}
59
60#endif
61
62#ifdef CONFIG_PARAVIRT_XXL
63#include <asm/paravirt.h>
64#else
65#ifndef __ASSEMBLY__
66#include <linux/types.h>
67
68static __always_inline unsigned long arch_local_save_flags(void)
69{
70 return native_save_fl();
71}
72
73static __always_inline void arch_local_irq_disable(void)
74{
75 native_irq_disable();
76}
77
78static __always_inline void arch_local_irq_enable(void)
79{
80 native_irq_enable();
81}
82
83/*
84 * Used in the idle loop; sti takes one instruction cycle
85 * to complete:
86 */
87static inline __cpuidle void arch_safe_halt(void)
88{
89 native_safe_halt();
90}
91
92/*
93 * Used when interrupts are already enabled or to
94 * shutdown the processor:
95 */
96static inline __cpuidle void halt(void)
97{
98 native_halt();
99}
100
101/*
102 * For spinlocks, etc:
103 */
104static __always_inline unsigned long arch_local_irq_save(void)
105{
106 unsigned long flags = arch_local_save_flags();
107 arch_local_irq_disable();
108 return flags;
109}
110#else
111
112#ifdef CONFIG_X86_64
113#ifdef CONFIG_DEBUG_ENTRY
114#define SAVE_FLAGS pushfq; popq %rax
115#endif
116
117#endif
118
119#endif /* __ASSEMBLY__ */
120#endif /* CONFIG_PARAVIRT_XXL */
121
122#ifndef __ASSEMBLY__
123static __always_inline int arch_irqs_disabled_flags(unsigned long flags)
124{
125 return !(flags & X86_EFLAGS_IF);
126}
127
128static __always_inline int arch_irqs_disabled(void)
129{
130 unsigned long flags = arch_local_save_flags();
131
132 return arch_irqs_disabled_flags(flags);
133}
134
135static __always_inline void arch_local_irq_restore(unsigned long flags)
136{
137 if (!arch_irqs_disabled_flags(flags))
138 arch_local_irq_enable();
139}
140#endif /* !__ASSEMBLY__ */
141
142#endif
143

source code of linux/arch/x86/include/asm/irqflags.h