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/*
12 * Interrupt control:
13 */
14
15/* Declaration required for gcc < 4.9 to prevent -Werror=missing-prototypes */
16extern inline unsigned long native_save_fl(void);
17extern __always_inline unsigned long native_save_fl(void)
18{
19 unsigned long flags;
20
21 /*
22 * "=rm" is safe here, because "pop" adjusts the stack before
23 * it evaluates its effective address -- this is part of the
24 * documented behavior of the "pop" instruction.
25 */
26 asm volatile("# __raw_save_flags\n\t"
27 "pushf ; pop %0"
28 : "=rm" (flags)
29 : /* no input */
30 : "memory");
31
32 return flags;
33}
34
35static __always_inline void native_irq_disable(void)
36{
37 asm volatile("cli": : :"memory");
38}
39
40static __always_inline void native_irq_enable(void)
41{
42 asm volatile("sti": : :"memory");
43}
44
45static __always_inline void native_safe_halt(void)
46{
47 mds_idle_clear_cpu_buffers();
48 asm volatile("sti; hlt": : :"memory");
49}
50
51static __always_inline void native_halt(void)
52{
53 mds_idle_clear_cpu_buffers();
54 asm volatile("hlt": : :"memory");
55}
56
57#endif
58
59#ifdef CONFIG_PARAVIRT_XXL
60#include <asm/paravirt.h>
61#else
62#ifndef __ASSEMBLY__
63#include <linux/types.h>
64
65static __always_inline unsigned long arch_local_save_flags(void)
66{
67 return native_save_fl();
68}
69
70static __always_inline void arch_local_irq_disable(void)
71{
72 native_irq_disable();
73}
74
75static __always_inline void arch_local_irq_enable(void)
76{
77 native_irq_enable();
78}
79
80/*
81 * Used in the idle loop; sti takes one instruction cycle
82 * to complete:
83 */
84static __always_inline void arch_safe_halt(void)
85{
86 native_safe_halt();
87}
88
89/*
90 * Used when interrupts are already enabled or to
91 * shutdown the processor:
92 */
93static __always_inline void halt(void)
94{
95 native_halt();
96}
97
98/*
99 * For spinlocks, etc:
100 */
101static __always_inline unsigned long arch_local_irq_save(void)
102{
103 unsigned long flags = arch_local_save_flags();
104 arch_local_irq_disable();
105 return flags;
106}
107#else
108
109#ifdef CONFIG_X86_64
110#ifdef CONFIG_DEBUG_ENTRY
111#define SAVE_FLAGS pushfq; popq %rax
112#endif
113
114#endif
115
116#endif /* __ASSEMBLY__ */
117#endif /* CONFIG_PARAVIRT_XXL */
118
119#ifndef __ASSEMBLY__
120static __always_inline int arch_irqs_disabled_flags(unsigned long flags)
121{
122 return !(flags & X86_EFLAGS_IF);
123}
124
125static __always_inline int arch_irqs_disabled(void)
126{
127 unsigned long flags = arch_local_save_flags();
128
129 return arch_irqs_disabled_flags(flags);
130}
131
132static __always_inline void arch_local_irq_restore(unsigned long flags)
133{
134 if (!arch_irqs_disabled_flags(flags))
135 arch_local_irq_enable();
136}
137#endif /* !__ASSEMBLY__ */
138
139#endif
140

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